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Target models and waveform design for detection in MIMO radar

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Science China(Information Sciences) 2014年第1期57卷 268-279页

作者： TANG jun LUO jun TANG bo DU JinSong Electronic Engineering Department of Tsinghua University China Marine Development & Research Center Shenyang Institute of Automation Chinese Academy of Sciences

In this paper,we propose a general target model for multiple-input multiple-output(MIMO)*** types of targets are *** each type of target,we develop a corresponding optimum waveform designing method to optimize detection *** on Chernof-Stein lemma,we use relative entropy as the performance *** show that the optimum waveform designing method can obtain better detection performance than traditional orthogonal waveform designing method.

关键词： MIMO radar waveform designing relative entropy

Adaptive sliding mode output tracking control based-FODOB for a class of uncertain fractional-order nonlinear time-delayed systems

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Science China(Technological Sciences) 2020年第9期63卷 1854-1862页

作者： WANG Zhen WANG XinHe xia JianWei SHEN Hao MENG bo College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao266590China School of Mathematics Science Liaocheng UniversityLiaocheng252059China School of Electrical Engineering and Information Anhui University of TechnologyMaanshan243002China

An adaptive sliding mode control(ASMC) method, based on fractional-order disturbance-observer(FODOB), is presented for a class of fractional-order nonlinear time-delay systems(FONTDS) with uncertainties to solve the target output tracking *** external disturbances are estimated by FODOB, and the unknown internal perturbations of the system are adaptively estimated by sliding mode control(SMC). Furthermore, Gronwall's inequality approach is used to ensure that the output tracking error is uniformly bounded for FONTDS. Firstly, a fractional-order sliding mode control(FOSMC) based FODOB is proposed for a fractional-order linear time-delay system(FOLTDS). Secondly, combined with adaptive estimation, the ASMC of FONTDS is studied. Finally, a numerical example of FONTDS is used to verify the effectiveness of the proposed methods.

关键词： adaptive sliding mode control fractional-order disturbance-observer time-delay uncertainty

Influence of longitudinal-torsional ultrasonic-assisted vibration on micro-hole drilling Ti-6Al-4V

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Chinese Journal of Aeronautics 2021年第9期34卷 247-260页

作者： Guofu GAO Ziwen xia Zhaojie YUAN Daohui xiaNG bo ZHAO School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

As Ti-6 Al-4 V is a typical hard to machine material,especially in micro drilling aviation parts,chip breaking difficulty is of increasing interest to explore its further *** this study,Longitudinal-Torsional Ultrasonic Assisted Drilling(LTUAD)was employed to machine Ti-6 Al-4 V,and its feasibility was evaluated by comparing with Conventional Drilling(CD).By combining periodical characteristics and vibration models(the separated or the unseparated ultrasonic elliptical vibration),the influence of ultrasonic frequency on the intersection characteristics of trajectories were *** the intersection characteristics were divided into four categories:even periodicity,odd periodicity,non-odd and even periodicity and composite periodicity,indicating different capability for chip *** applying the longitudinal-torsional compound vibration horn,the micro-hole drilling experiment was carried out on machining *** chip morphology,the thrust force,and the burr height were *** results showed that the morphology of chips presented as smaller and more fragmentary ones in LTUAD compared with continuous helical conical ones and fold-shaped ones in *** with CD,the average values of the thrust force in LTUAD reduced by 1.98%to 24.9%.According to the burr around the hole exit in both LTUAD and CD,the height of the latter was greatly affected by the drilling *** the burr around the exit of the hole were distributed rather evenly with smaller extension in ***,the LTUAD employed in micro-hole drilling was effective.

关键词： Capability for chip breaking Longitudinal-torsional ultrasonic assisted drilling Micro-hole drilling Periodical characters Ti-6Al-4V

Structure of Independent Sets in Direct Products of Some Vertex-transitive Graphs

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Acta Mathematica Sinica,English Series 2012年第4期28卷 697-706页

作者： Xing bo GENG jun WANG Hua jun ZHANG School of Mathematical Science Dalian University of Technology Department of Mathematics Shanghai Normal University Department of Mathematics Zhejiang Normal University

Let Circ（r, n） be a circular graph. It is well known that its independence number α（Circ（r, n）） = r. In this paper we prove that for every vertex transitive graph H, and describe the structure of maximum independent sets in Circ（r, n） × H. As consequences, we prove for G being Kneser graphs, and the graphs defined by permutations and partial permutations, respectively. The structure of maximum independent sets in these direct products is also described.

关键词： Vertex-transitivity primitivity independence number

Deep learning-based open API recommendation for Mashup development

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Science China(Information Sciences) 2023年第7期66卷 94-111页

作者： Ye WANG junwu CHEN Qiao HUANG Xin xia bo JIANG School of Computer and Information Engineering Zhejiang Gongshang University Software Engineering Application Technology Lab

Mashup developers often need to find open application programming interfaces(APIs) for their composition application development. Although most enterprises and service organizations have encapsulated their businesses or resources online as open APIs, finding the right high-quality open APIs is not an easy task from a library with several open APIs. To solve this problem, this paper proposes a deep learning-based open API recommendation(DLOAR) approach. First, the hierarchical density-based spatial clustering of applications with a noise topic model is constructed to build topic models for Mashup clusters. Second,developers’ requirement keywords are extracted by the Text Rank algorithm, and the language model is built. Third, a neural network-based three-level similarity calculation is performed to find the most relevant open APIs. Finally, we complement the relevant information of open APIs in the recommended list to help developers make better choices. We evaluate the DLOAR approach on a real dataset and compare it with commonly used open API recommendation approaches: term frequency-inverse document frequency, latent dirichlet allocation, Word2Vec, and Sentence-BERT. The results show that the DLOAR approach has better performance than the other approaches in terms of precision, recall, F1-measure, mean average precision,and mean reciprocal rank.

关键词： Mashup development open API recommendation deep learning neural network service discovery

Information gain based sensor search scheduling for low-earth orbit constellation estimation

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Journal of Systems Engineering and Electronics 2011年第6期22卷 926-932页

作者： bo Wang jun Li Wei An Yiyu Zhou School of Electronics and Engineering National University of Defense Technology Changsha 410073 R R. China Institute of Radar and Electronic Warfare Equipment Academy of Air Force Beijing 100085 P. R. China

This paper addresses the problem of sensor search scheduling in the complicated space environment faced by the low-earth orbit *** search scheduling methods based on the commonly used information gain are compared via simulations *** a novel search scheduling method in the scenarios of uncertainty observation is proposed based on the global Shannon information gain and beta density based uncertainty *** results indicate that the beta density model serves a good option for solving the problem of target acquisition in the complicated space environments.

关键词： low-earth orbit constellation sensor network scheduling algorithm information gain acquisition.

Aggregation-induced emission luminogens reveal cell cycle-dependent telomerase activity in cancer cells

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National Science Review 2021年第6期8卷 70-79页

作者： xia Wu jun Wu jun Dai Biao Chen Zhe Chen Shixuan Wang Feng Wu xiaoding Lou Fan xia Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of Geosciences Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology

Telomerase acts as an important biomarker for tumor identification, and synthesizes telomeric repeats at the end of chromosome telomeres during the replicative phase of the cell cycle; thus, the expression level of telomerase changes as the cell cycle progresses. TERT m RNA expression and telomerase activity were significantly increased in over 80% of human cancers from tissue specimens. Although many efforts have been made in detecting the activity of TERT m RNA and active telomerase, the heterogeneous behavior of the cell cycle was overlooked, which might affect the accuracy of the detection results. Herein, the AIEgen-based biosensing systems of Py TPA-DNA and Silole-R were developed to detect the cellular level of TERT m RNA and telomerase in different cell cycles. As a result, the fluorescence signal of cancer cells gradually increased from G0/G1, G1/S to S phase. In contrast, both cancer cells arrested at G2/M phase and normal cells exhibited negligible fluorescence intensities. Compared to normal tissues, malignant tumor samples demonstrated a significant turn-on fluorescence signal. Furthermore, the transcriptomics profiling revealed that tumor biomarkers changed as the cell cycle progressed and biomarkers of CA9, TK1 and EGFR were more abundantly expressed at early S stage. In this vein, our study presented advanced biosensing tools for more accurate analysis of the cell-cycle-dependent activity of TERT m RNA and active telomerase in clinical tissue samples.

关键词： cell cycle TERT mRNA telomerase activity AIEgens biomarkers

Development of defoliating insects and their preferences for host plants under varying temperatures in a subtropical evergreen forest in eastern China

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Frontiers of Earth Science 2017年第2期11卷 321-331页

作者： jun JING Lingdan xia Kai LI School Of Life Sciences East China Normal University Shanghai 200241 China Shanghai Key Laboratory for Urban Ecology Processes and Eco-Restoration East China Normal University Shanghai 200241 China

Abstract The aim of this work was to understand the development of defoliating insects and their preferences for host plants under varying temperatures in a subtropical evergreen broad-leaved forest in China. We measured the main developmental parameters of three typical defoliating insects （i.e., Ourapteryx ebuleata szechuana, Biston marginata, and Euproctis angulata） and their preferences for five host plants at temperatures from 16~C to 31 ~C at 3~C intervals in the Tiantong National Forest Research station in eastern China. The results showed the following. 1） An appropriate rise in temperature increases the survival rate with an increase in the number of offspring. The developmental durations for these three insects were shortened, and pupal weight increased with an increase in temperature. 2） A shift in the preference for host plants for these three insects was observedat elevated tempera- tures. They all preferred to feed on Schima superba and Castanopsis sclerophylla at elevated temperatures, show- ing an opposite response to the other three plants. The daily leaf consumption of the three insects was positively correlated with their feeding preference, with more leaves being consumed from the plants they preferred. 3） For O. ebuleata szechuana larvae, daily leaf consumption initially increased and then decreased with increasing temperatures. In contrast, Biston marginata and Euproctis angulata larvae consumed more leaves at elevated temperatures. The feeding preferences of O. ebuleata szechuana and Biston marginata were more sensitive to changing temperatures than that of Euproctis angulata laevae. We concluded that increased numbers of offspring and generations, pupal weights, and a shift in preference to two plants for these three defoliating insects might lead to severe damage to these two plants which would enhance the fragmentation and decrease the stability of the forest communities under changing temperatures. Meanwhile, the variations in the response

关键词： defoliating insects elevated temperature,development dynamics feeding behavior subtropical evergreen forest

Hollow MOF capsule encapsulated amino-functionalized ionic liquid for excellent CO_(2) catalytic conversion

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Chinese Journal of Chemical Engineering 2021年第12期34卷 124-130页

作者： bo-Yun Liu Min-Jie Chen Liang Yang bo Zhao Tao xia Gang-Gang Chang School of Power Engineering Naval University of EngineeringWuhan 430033China School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China

The engineering of highly efficient and stable heterogeneous catalysts for catalytic conversion of CO_(2) to high value-added products is highly desirable but presents a great challenge. Herein, we reported the synthesis of a series of multifunctional IL@H-Zn/Co-ZIF composite catalysts with a unique porous hollow capsule structure and encapsulated amino-functionalized ionic liquids(ILs). The unique hollow capsule structure of IL@H-Zn/Co-ZIF provides sufficient space for loading active ILs([C_(2)NH_(2) Mim+][Brà]) and fast mass transfer of substrate molecules during catalysis. Furthermore, the microporous Zn-ZIF shell can effectively avoid the leaching of active ILs. Benefiting from the unique hollow structure, the resultant IL@H-Zn/Co-ZIF demonstrated excellent catalytic performance(>95% yield), and good recyclability(still remained about 90% activities after 5 cycles) when applied in the CO_(2) cycloaddition reaction under solvent and co-catalyst free conditions.

关键词： MOFs Catalyst Hollow capsule CO_(2)capture Ionic liquids