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The Yield and Water Use Efficiency to First Cutting Date of Siberian Wildrye in North China

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Agricultural Sciences in China 2011年第11期10卷 1716-1722页

作者： LI zi-zhong ZHANG Wei-hua GONG Yuan-shi Department of Soil and Water Sciences China Agricultural University Beijing 100193 P.R.China

A field experiment study was conducted in Bashang Plateau in North China in 2008 to determine the effect of three first cutting dates on the growth and water use efficiency （wuE） of Siberian wildrye （Elymus sibiricus L.） in the agropastoral ecotone of North China （APENC）. The experiment was conducted in a split plot design with three replications with water supply regime as the main plot treatment and first cutting date as the subplot treatment. Two water supply regimes were used, which included rain-fed treatment as control （CK） and a single irrigation and straw mulch treatment （W）. Three first cutting date treatments were conducted at early heading stage on July 1 （E）, at late heading stage on July 12 （L）, and at flowering stage on July 27 （F）, respectively. The results showed that the forage yield and wuE were the lowest at early heading stage harvest, while the highest at flowering stage either in CK or W treatment. Under combined CK and W treatments, average forage yields of the F subplots were 2 900 and 6 703 kg ha-~, and the values of wuE were 0.82 and 2.28 kg m-3, respectively. Under the CK treatment, forage yields of the E and L subplots were 43.8 and 41.9% lower than the F subplots, and their values of wuE were 46.2 and 50.3% lower than F, respectively. Under the W treatment, the forage yields of the E and L subplots were 74.9 and 61.6% lower, and their values of wuE were 78.1 and 63.3% lower, respectively, as compared with F subplots. Therefore, earlier first cutting did not increase the regrowth of Siberian wildrye and improve the mismatch between rainy season and the period of high growth potential of the grass in the semiarid APENC.

关键词： siberian wildrye first cutting date forage yield water use efficiency North China

Genetic Pleiotropy Test by Quasi p-Value with Application to Typhoon Data in China

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Journal of Systems Science & Complexity 2022年第4期35卷 1557-1572页

作者： wu Qiang zhong Shaojun TONG Xingwei School of Statistics Beijing Normal UniversityBeijing100875China School of Mathematics and Statistics Hubei University of Science and TechnologyHubei437000China

To test genetic pleiotropy,the main difficulty lies in the failure to find a test statistic and calculate its p-value for determining whether to reject the null hypothesis or *** deal with this issue,the authors propose a quasi p-value,which plays the similar role as the usual p-value in genetic pleiotropy *** the formula of the quasi p-value,the main task is to determine the *** this paper,the authors present two weighted methods based on the Bayesian rule and extend the proposed methods to study a single binary trait using a data-driven EM *** simulation studies are conducted for the assessment of the two proposed methods and illustrate that the proposed methods improve the performance of power by comparing with the two-stage *** addition,the authors apply the proposed methods to the data of tropical storms that occurred on the mainland of China since 1949,investigating the relationship between the landing site and predictive features of tropical storms,and showing that the landing site has a large influence on at least two features of typhoon.

关键词： Bayesian rule data-driven EM algorithm genetic pleiotropy quasi p-value

Research Progress of Tip Winglet Technology in Compressor

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Journal of Thermal Science 2021年第1期30卷 18-31页

作者： zhong Jingjun wu Wanyang HAN Shaobing Merchant Marine College Shanghai Maritime UniversityShanghai 201306China Naval Architecture and Ocean Engineering College Dalian Maritime UniversityDalian 116026China

In the present study,the research progress of tip winglets that control tip clearance leakage flow in compressors is ***,the effects of tip leakage flow on the aerodynamic performance of the compressor are ***,the development of tip winglet technology is ***,a series of studies on compressor tip winglet technology are ***,the effects of tip winglets on the aerodynamic performance of rectangular cascades of low-speed and high-subsonic compressors,subsonic compressor rotor and transonic compressor rotor are discussed,respectively,and the control effect of tip winglet technology combined with tip groove design on tip leakage is ***,the subsequent development direction and research prospect of compressor tip winglet technology are presented.

关键词： blade tip winglet compressor tip leakage flow tip leakage vortex

Recent advances in catalytic conversion of carbon dioxide to propiolic acids over coinage-metal-based catalysts

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Journal of Energy Chemistry 2021年第8期30卷 572-580,I0012页

作者： Tianyu Zhang Jiawei zhong Zhilian wu Department of Chemistry Joint Institute for Advanced MaterialsUniversity of Tennessee37996 KnoxvilleUnited States Department of Chemical and Biomolecular Engineering National University of Singapore4 Engineering Drive117585 SingaporeSingapore Ningbo Fengcheng Advanced Energy Materials Research Institute Co. Ltd.Ningbo 315500China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518055China

The conversion of inexpensive,available C1 feedstock of carbon dioxide(CO_(2))into value-added fine chemicals via homogeneous or heterogeneous catalysis has attracted great recent ***-based(Cu,Ag,and Au)catalysis has emerged as a synthetic strategy for a wide range of organic chemical reactions in past *** coinage-metal-catalyzed carboxylation,CO_(2)is adopted as a carboxylation reagent,while coinage-metal salts,complexes,and nanoparticles(NPs)serve as a Lewis acid catalyst to activate unsaturated chemicals,particularly *** mini-review focuses on the recent advances of coinage-metal-catalyzed carboxylation of terminal alkynes with CO_(2).Other respects,such as the role of bases,the influence of trace water,and solvent effects are also highlighted.

关键词： Carbon dioxide Terminal alkynes Propiolic acids Catalysis

A Visual-Based Gesture Prediction Framework Applied in Social Robots

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IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 510-519页

作者： Bixiao wu Junpei zhong Chenguang Yang College of Automation Science and Engineering South China University of TechnologyGuangzhou 510640China IEEE School of Intelligent Engineering South China University of TechnologyGuangzhou 511442China

In daily life,people use their hands in various ways for most daily *** are many applications based on the position,direction,and joints of the hand,including gesture recognition,gesture prediction,robotics and so *** paper proposes a gesture prediction system that uses hand joint coordinate features collected by the Leap Motion to predict dynamic hand *** model is applied to the NAO robot to verify the effectiveness of the proposed *** of all,in order to reduce jitter or jump generated in the process of data acquisition by the Leap Motion,the Kalman filter is applied to the original *** some new feature descriptors are *** length feature,angle feature and angular velocity feature are extracted from the filtered *** features are fed into the long-short time memory recurrent neural network(LSTM-RNN)with different *** results show that the combination of coordinate,length and angle features achieves the highest accuracy of 99.31%,and it can also run in real ***,the trained model is applied to the NAO robot to play the finger-guessing *** on the predicted gesture,the NAO robot can respond in advance.

关键词： Finger-guessing game gesture prediction human-robot interaction long-short time memory recurrent neural network(LSTM-RNN) social robot

A THEORETICAL MODEL FOR THERMAL-SENSITIVE MICROGEL WITH PNIPAM CORE AND ELASTIC SHELL

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Acta Mechanica Solida Sinica 2012年第5期25卷 520-529页

作者： Zhen wu Zheng zhong School of Aerospace Engineering and Applied Mechanics Tongji Universityshanghai 200092China

Poly （N-isopropylacrylamide）（PNIPAM） microgels are widely used in drug delivery due to their fast response to temperature. In order to get a better biocompatibility, PNIPAM mi- crogels are typically coated with a layer of biocompatible material, resulting in composite microgels with core-shell structure. In a composite microgel prepared recently, for example, a microsphere of PNIPAM gel is enclosed by a phospholipid membrane, and the composite microgel exhibits a substantial volume transition in response to temperature changes. Here we develop a theoretical model to describe the thermal-responsive behavior of this composite microgel. In particular, we treat the phospholipid membrane as an elastic layer behaving like rubber-like elastomers and adopt the form of the free-energy function for nematic gels （which refer to anther species of thermal- sensitive gels whose behavior has been intensively studied） as that for PNIPAM gels. We show that the thermal-responsive behavior of the composite microgel can be markedly influenced by the membrane. By investigating the state of stress on the interface, we further predict that when the coating membrane is stiff and thin, wrinkles are expected to occur on the outer surface of the composite microgel after the volume transition.

关键词： gel poly (N-isopropylacrylamide) volume transition core-shell structure

On cutting sequences of the L-shaped translation surface tiled by three squares

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Science China Mathematics 2015年第6期58卷 1311-1326页

作者： wu ShengJian zhong YuMin LMAM and School of Mathematical Sciences Peking University

We consider a symbolic coding of bi-infinite non periodic geodesics on the L-shaped translation surface tiled by three squares. Each bi-infinite non periodic geodesic is associated with a cutting sequence corresponding to the sequence of labeled saddle connections hit. We prove that there is a relationship between the cutting sequences and the actions of some affine automorphisms of the translation surface. We also get an explicit formula to determine the direction of a bi-infinite non periodic geodesic by using the corresponding cutting sequence.

关键词： affine shaped cutting labeled intersection letter infinite compatible saddle explicit

Role of Hiraoka's transurethral detachment of the prostate combined with biopsy of the peripheral zone during the same session in patients with repeated negative biopsies in the diagnosis of prostate cancer

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World Journal of Clinical Cases 2020年第11期8卷 2219-2226页

作者： Chun-Yu Pan Bin wu zi-Chuan Yao Xian-Qing Zhu Yun-zhong Jiang Song Bai Department of Urology Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina

BACKGROUND Persistent suspicion of prostate cancer(PCa)due to a rising prostate-specific antigen(PSA)level after repeated negative biopsies is a serious challenge in clinical *** To determine the role of Hiraoka’s transurethral detachment of the prostate(TUDP)combined with biopsy of the peripheral zone during the same session in patients with repeated negative biopsies in the diagnosis of *** We retrospectively evaluated the records of 10 patients who were eligible for inclusion in our hospital between December 2012 and August *** demographics,a family history of PCa,the number of biopsies,prostate volume,pathological examination,and perioperative PSA level were *** Two of 10 patients were pathologically diagnosed with PCa after surgery;the Gleason scores were 4+4 and 4+3,*** patients subsequently underwent laparoscopic radical *** median PSA levels preoperatively,and 3 mo and 1 year postoperatively in the other eight patients who were diagnosed with benign prostate hyperplasia after surgery were 19.10 ng/mL,1.10 ng/mL,and 1.15 ng/mL,*** adjusted P values of the 3-mo and 1-year post-operative PSA level vs pre-operative PSA level were 0.003 and 0.026,*** of the patients had increased PSA levels or PCa detected after a median 35 mo of *** TUDP combined with peripheral zone biopsy may improve the detection rate of PCa in patients with repeated negative *** PSA level declined rapidly in patients who had negative pathological examinations after TUDP,which remained stable 1 year after surgery.

关键词： Prostate cancer Biopsy Transurethral detachment of prostate Transurethral resection of the prostate Prostate-specific antigen Hiraoka’s transurethral detachment of the prostate

Visualization of hydraulic fracture interacting with pre-existing fracture

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Petroleum Science 2023年第6期20卷 3723-3735页

作者： zi-Xiao Xie Xiao-Guang wu Teng-Da Long zhong-Wei Huang Gen-Sheng Li Wen-Chao Zou Zhao-Wei Sun State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum-BeijingBeijing102249China

Hydraulic fracturing is considered the main stimulation method to develop shale gas reservoirs. Due to its strong heterogeneity, the shale gas formation is typically embedded with geological discontinuities such as bedding planes and natural fractures. Many researchers realized that the interaction between natural fractures and hydraulic fractures plays a crucial role in generating a complex fracture network. In this paper, true tri-axial hydraulic fracturing tests were performed on polymethyl methacrylate (PMMA), on which pre-existing fracture was pre-manufactured to simulate natural fracture. A cohesive model has been developed to verify the results of the experimental tests. The key findings demonstrate that the experimental results agreed well with the numerical simulation outcomes where three main interaction modes were observed: crossing;being arrested by opening the pre-existing fracture;being arrested without dilating the pre-existing fracture. Crossing behavior is more likely to occur with the approaching angle, horizontal stress difference, and injection rate increase. Furthermore, the higher flow rate might assist in reactivating the natural fractures where both sides of the pre-existing fractures were reactivated as the injection rate increased from 5 to 20 mL/min. Additionally, hydraulic fractures show a tendency to extend vertically rather than along the direction of maximum horizontal stress when they are first terminated at the interface. This research may contribute to the field application of hydraulic fracturing in shale gas formation.

关键词： Hydraulic fracturing Natural fracture Fracture propagation Interaction mode PMMA