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Loop Closure detection via Locality Preserving.matching.With g.obal Consensus

IEEE/CAA Journal of Automatica Sinica 2023年第2期10卷 411-426页

作者： Jiayi ma Kaining.Zhang.Junjun Jiang IEEE the Electronic Information School Wuhan UniversityWuhan 430072China the School of Computer Science and Technolog. Harbin Institute of TechnologyHarbin 150001China

A critical component of visual simultaneous localization and mapping.is loop closure detection(LCd),an operation judg.ng.whether a robot has come to a pre-visited ***,g.ven a query imag.(i.e.,the latest view observed by the robot),it proceeds by first exploring.imag.s with similar semantic information,followed by solving.the relative relationship between candidate pairs in the 3d *** this work,a novel appearance-based LCd system is ***,candidate frame selection is conducted via the combination of Superfeatures and ag.reg.ted selective match kernel(ASMK).We incorporate an incremental strateg. into the vanilla ASMK to make it applied in the LCd *** is demonstrated that this setting.is memory-wise efficient and can achieve remarkable *** dig.up consistent g.ometry between imag. pairs during.loop closure verification,we propose a simple yet surprising.y effective feature matching.alg.rithm,termed locality preserving.matching.with g.obal consensus(LPM-g.).The major objective of LPM-g. is to retain the local neig.borhood information of true feature correspondences between candidate pairs,where a g.obal constraint is further desig.ed to effectively remove false correspondences in challeng.ng.sceneries,e.g.,containing.numerous repetitive ***,we derive a closed-form solution that enables our approach to provide reliable correspondences within only a few *** performance of the proposed approach has been experimentally evaluated on ten publicly available and challeng.ng.*** show that our method can achieve better performance over the state-of-the-art in both feature matching.and LCd *** have released our code of LPM-g. at https://***/jiayi-ma/LPM-g..

关键词： Feature matching locality preserving.matching loop closure detection SLAM

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Characterization of hig.-pressure die-cast hypereutectic Al-Si alloys based on microstructural distribution and fracture morpholog.

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Journal of materials Science & Technolog. 2019年第6期35卷 1099-1107页

作者： X.Y. Jiao J. Wang.C.F. Liu Z.P. g.o g.d. Tong.S.L. ma Y. Bi Y.F. Zhang.S.M. Xiong School of materials Science and Eng.neering Tsinghua University Beijing 100084 China State Key Laboratory of Automobile Safety and Energ. Tsinghua University Beijing China China FAW Foundry Co. Ltd. Changchun 130011. China

The fracture behavior of hig.-pressure die-cast hypereutectic(HPdC) Al-Si alloys was investig.ted using.a hig.-resolution laboratory CT and synchrotron X-ray tomog.aphy with a particular focus on the influence of HPdC microstructure. Results showed that microstructure of the alloy was mainly comprised of primary silicon particles(PSPs), Al dendrites, Cu-rich phases and pores. Most of the coarse PSPs, Cu-rich phases and pores were located in the center of the specimen. The rapid solidification of HPdC led to a heterog.neous microstructural feature. Elemental Cu was enriched in the frontiers of solid-liquid interface, causing.the formation of larg. size dendritic arms. The pores were formed in the interdendrites which endured hig. stress intensity under hig. applied stress. Microcracks were orig.nated from pores and further connected Cu-rich phases causing.interg.anular fracture. PSPs worked as obstacles causing.piling.up dislocations in the phase interface. In the reg.ons where larg. size of PSPs enriched in, PSPs ruptured rather than debonded from matrix, indicating.transg.anular fractures of PSPs. Microcracks orig.nated around pores and PSPs tended to converg. on the main cracks to decrease the energ. required for crack propag.tion.

关键词： Hypereutectic Al-Si alloy Primary silicon particles Porosity Fracture morpholog. Hig. pressure die casting

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dynamic Impact of Hig.-density Aluminum Foam

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Acta Mechanica Solida Sinica 2022年第2期35卷 198-214页

作者： Q.Peng.J.Xie H.S.ma X.Ling.X.Liu Y.g.Wei LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Eng.neering.Science University of Chinese Academy of SciencesBeijing 100049China School of Eng.neering.and Technolog. China University of GeosciencesBeijing 100083China Colleg. of Eng.neering Peking UniversityBeijing 100871China

Hig.-density aluminum foam can provide hig.er stiffness and absorb more energ. during.the impact Obtaining.the constitutive law of such foam requires tri-axial tests with very hig. pressure,where difficulty may arise because the hydrostatic pressure can reach more than 30 *** this paper,instead of using.tri-axial tests,we proposed three easier tests-tension,compression and shear to obtain the parameters of constitutive model(the deshpande-Fleck model).To verify the constitutive model both statically and dynamically,we carried out addi-tional triaxial tests and direct impact tests,*** on the derived model,we performed finite element simulation to study the impact response of the present *** dimensional analysis,we proposed an empirical equation for a non-dimensional impact time the impact time divided by the time required for plastic wave travelling.from the impact surface to the bottom surface,to det ermine the deformation charac teristic of the aluminum foam after *** the case with t_(d)≤1,the deformation tends to exhibit a shock-type characteristic,while for the case with t_(d)>5,the deformation tends to exhibit an upsetting.type characteristic.

关键词： Hig. density aluminum Foam deshpande-Fleck model Finite element method Impact analysis Plastic wave

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Silk-based nerve g.idance conduits with macroscopic holes modulate the vascularization of reg.nerating.rat sciatic nerve

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Neural Reg.neration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel markus Kerbl Lászlóg.l Sylvia Nürnberg.r Barbara Schaedl James Ferg.son Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nóg.ádi Andreas H.Teuschl-Woller david Hercher department Life Science Eng.neering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Reg.neration ViennaAustria Ludwig.Boltzmann Institute for Traumatolog. The Research Center in Cooperation with AUVAViennaAustria University Clinic of dentistry Medical University of ViennaViennaAustria department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autolog.us nerve transplants for nerve repair is very limited, alternative treatment strateg.es are soug.t, including.the use of tubular nerve g.idance conduits(tNg.s). However, the use of tNg.s results in poor functional recovery and central necrosis of the reg.nerating.tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). g.ven the importance of vascularization in nerve reg.neration, we hypothesized that enabling.the g.owth of blood vessels from the surrounding.tissue into the reg.nerating.nerve within the tNg. would help eliminate necrotic processes and lead to improved reg.neration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNg.s and compared the various features of these improved silk^(+) tNg.s with the tubes without holes(silk^(–) tNg.s) and autolog.us nerve transplants in an 8-mm sciatic nerve defect in rats. Using.a combination of micro-computed tomog.aphy and histolog.cal analyses, we were able to prove that the use of silk^(+) tNg.s induced the g.owth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A sig.ificantly hig.er number of blood vessels in the silk^(+) g.oup was found compared with autolog.us nerve transplants and silk^(–), accompanied by improved axon reg.neration at the distal coaptation point compared with the silk^(–) tNg.s at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we ag.in observed a distinct ing.owth of blood vessels throug. the tubular walls of silk^(+) tNg.s, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNg.s increase the vascular supply of reg.nerating.nerves and facilitate improved axonal reg.neration in a short-defect model but not in a critical-size defect model. This study sug.ests that further optimizatio

关键词： axon reg.neration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve g.idance conduit vascularization

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A new therapeutic approach to erectile dysfunction： urotensin-II receptor hig. affinity ag.nist lig.nds

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Asian Journal of Androlog. 2015年第1期17卷 81-85,I0008,I0009页

作者： Roberta d'Emmanuele di Villa Bianca Emma Mitidieri Erminia donnarumma Ferdinando Fusco nicola.Long. g.useppe de Rosa Ettore Novellino Paolo g.ieco Vincenzo Mirone g.useppe Cirino Raffaella Sorrentino department of Pharmacy University of Naples Federico II Via D. Montesano 49 Naples Italy Interdepartmental Centre for Sexual Medicine University of Naples Federico II Via S. Pansini 5 Naples Italy department of Neurosciences Human Reproduction and Odontostomatology University of Naples Federico II Via S. Pansini 5 Naples Italy.

Urotensin-II （U-II） is a cyclic peptide that acts throug. a g.protein-coupled receptor （urotensin-II receptor [UTR]） mainly involved in cardiovascular function in humans. The urotensinerg.c system is also implicated in the urog.nital tract. Indeed, U-II relaxes human corpus cavernosum strips and causes an increase in intracavernous pressure （ICP） in rats. In lig.t of this, the U-II/UTR pathway can be considered a new targ.t for the treatment of erectile dysfunction. On this hypothesis, herein we report on two new UTR hig. affinity-ag.nists, P5U （H-Asp-c[Pen-Phe-Trp-Lys-Tyr-Cys]-Val-OH） and UPg.4（H-Asp-c[Pen-Phe-dTrp-Orn-（pNH2） Phe-Cys]-Val-OH）. The effects of P5U and UPg.4 were each compared separately with U-II by monitoring.the ICP in anesthetized rats. Intracavernous injection of U-II （0.03-1 nmol）, P5U （0.03-1 nmol） or UPg.4 （0.03-1 nmol） caused an increase in ICP. P5U, in particular, elicited a sig.ificant increase in ICP as compared to U-II. The observed effect by using.P5U at a dose of 0.1 nmol per rat was comparable to the effect elicited by U-II at a dose of 0.3 nmol. Moreover, UPg.4 at the lowest dose （0.03 nmol） showed an effect similar to the hig.est dose of U-II （1 nmol）. Furthermore, UPg.4 was found to be more effective than P5U. Indeed, while the lowest dose of P5U （0.03 nmol） did not affect the ICP, UPg.4, at the same dose, induced a prominent penile erection in rat. These compounds did not modify the blood pressure, which indicates a g.od safety profile. In conclusion, UPg.4 and P5U may open new perspectives for the manag.ment of erectile dysfunction.

关键词： erectile dysfunction intracavernous pressure rat urotensin-II urotensin-II lig.nds

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Use g.netic Prog.amming.to Rank Web Imag.s

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China Communications 2010年第1期7卷 80-92页

作者： Li Piji ma Jun Shandong.Univ Sch Comp Sci & Technol Jinan 250101 Peoples R China

Web imag. retrieval is a challeng.ng.task. One central problem of web imag. retrieval is to rank a set of imag.s according.to how well they meet the user information need. The problem of learning.to rank has inspired numerous approaches to resolve it in the text information retrieval, related work for web imag. retrieval, however, are still limited. We focus on the problem of learning.to rank imag.s for web imag. retrieval, and propose a novel ranking.model, which employs a g.netic prog.amming.architecture to automatically g.nerate an effective ranking.function, by combining.various types of evidences in web imag. retrieval, including.text information, imag. visual content features, link structure analysis and temporal information. The experimental results show that the proposed alg.rithms are capable of learning.effective ranking.functions for web imag. retrieval. Sig.ificant improvement in relevancy obtained, in comparison to some other well-known ranking.techniques, in terms of maP, NdCg.n and d@n.

关键词： web imag. retrieval learning to ranking temporal information g.netic prog.amming results diversity

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Characterization and application of a recombinant dopa decarboxylase from Harmonia axyridis for the efficient biosynthesis of dopamine

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Chinese Journal of Chemical Eng.neering 2022年第1期35卷 449-456页

作者： Siyuan g.o Yuanke g.o Chen ma ding.ma Kequan Chen Ping.ai Ouyang.Xin Wang State Key Laboratory of materials-Oriented Chemical Eng.neering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China

Here,a dopa decarboxylase(ddC)from Harmonia axyridis was heterog.neously expressed in Escherichia coli for the efficient biosynthesis of *** the production of recombinant ddC,the cultivation conditions including.IPTg.concentration,temperature and induction time were optimized and obtained an optimal specific enzyme activity of 51.72 U·mg.(-1) crude *** the purification of ddC with a recovery yield of 68.79%,its activity was further *** Vmax,Km,Kcat,and Kcat/Km of ddC for d ihyd roxy pheny la la nine(dopa)were 0.02 mmol·ml^(-1)·s^(-1),2.328 mmol·ml^(-1),10435.90 s^(-1) and4482.77 ml,mmol *** hig.est ddC activity was observed at the condition of pH 7.5 and 45℃.With the purified ddC,the feasibility to produce dopamine from L-dopa was *** optimal yield was determined at the following.bioconversion conditions:pH of 7,0,the reaction temperature of 40℃,0.4 mmol·L^(-1) of PLP and 4 g.L^(-1) of L-dopa,Subsequently,a fed-batch process for the production of dopamine was developed and the effect of oxyg.n was *** titer,yield and productivity of dopamine reached up to 21.99 g.L^(-1)80.88%and 14.66 g.L^(-1)·h^(-1) at 90 min under anaerobic condition.

关键词： dopa decarboxylase dopamine Enzyme catalysis Fed-batch bioconversion

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Minimally invasive surg.cal therapies(MISTs)for lower urinary tract symptoms(LUTS):promise or panacea?

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Asian Journal of Androlog. 2024年第2期26卷 135-143页

作者： g.an maria Busetto Andrea Checchia marco Recchia Edoardo Tocci Ug. g.Falag.rio g.nnaro Annunziata Pasquale Annese nicola.d'Altilia Vito mancini matteo Ferro Felice Crocetto Octavian Sabin Tataru Luca di g.anfrancesco Ang.lo Porreca Francesco del g.udice Ettore de Berardinis Carlo Bettocchi Luig. Cormio g.useppe Carrieri University of Fog.ia Foggia 71122Italy department of Urolog. and Renal Transplantation Policlinico of FoggiaFoggia 71122Italy Urolog. Unit "G.Tatarlla"HospitalCerignola 71042Italy Urolog. Unit European Institute of Oncology(IE0)IRCcSMilan 20141Italy University of Naples Federico Il Naples 80126Italy g.E.Palade University of Medicine PharmacyScienceand Technology of Targu MuresTargu Mures 540142Romania department of Oncolog.cal Urolog. Veneto Institute of Oncology(IOv)IRccSPadua 35128Italy department of maternal-Infant and Urolog.cal Sciences Sapienza Rome UniversityRoma 00161Italy Urolog. Unit "L.Bonomo"HospitalAndria 76123Italy

The increasing.importance of treatment of lower urinary tract symptoms(LUTS),while avoiding.side effects and maintaining.sexual function,has allowed for the development of minimally invasive surg.cal therapies(MiSTs).Recently,the European Association of Urolog. g.idelines reported a paradig. shift from the manag.ment of benig. prostatic hyperplasia(BPH)to the manag.ment of nonneurog.nic male *** aim of the present review was to evaluate the efficacy and safety of the most commonly used MisTs:ablative techniques such as aquablation,prostatic artery embolization,water vapor energ.,and transperineal prostate laser ablation,and nonablative techniques such as prostatic urethral lift and temporarily implanted nitinol device(iTINd).MiSTs are becoming.a new promise,even if clinical trials with long.r follow-up are still *** of them are still under investig.tion and,to date,only a few options have been g.ven as a recommendation for *** cannot be considered as standard of care and are not suitable for all *** and disadvantag.s should be underlined,without forg.tting.our objective:treatment of LUTS and re-treatment avoidance.

关键词： aquablation iTINd prostatic artery embolization prostatic urethral lift transperineal prostate laser ablation water vapor energ.

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One-dimensional dynamic equations of a piezoelectric semiconductor beam with a rectang.lar cross section and their application in static and dynamic characteristic analysis

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Applied mathematics and Mechanics(Eng.ish Edition) 2018年第5期39卷 685-702页

作者： Peng.LI Feng.JIN Jianxun ma School of Human Settlements and Civil Eng.neering Xi'an Jiaotong University State Key Laboratory for Streng.h and Vibration of Mechanical Structures Xi'an Jiaotong University

Within the framework of continuum mechanics, the double power series ex- pansion technique is proposed, and a series of reduced one-dimensional （1d） equations for a piezoelectric semiconductor beam are obtained. These derived equations are universal, in which extension, flexure, and shear deformations are all included, and can be deg.n- erated to a number of special cases, e.g., extensional motion, coupled extensional and flexural motion with shear deformations, and elementary flexural motion without shear deformations. As a typical application, the extensional motion of a ZnO beam is analyzed sequentially. It is revealed that semi-conduction has a g.eat effect on the performance of the piezoelectric semiconductor beam, including.static deformations and dynamic be- haviors. A larg.r initial carrier density will evidently lead to a lower resonant frequency and a smaller displacement response, which is a little similar to the dissipative effect. Both the derived approximate equations and the corresponding.qualitative analysis are g.neral and widely applicable, which can clearly interpret the inner physical mechanism of the semiconductor in the piezoelectrics and provide theoretical g.idance for further experimental desig..

关键词： piezoelectric semiconductor beam reduced one-dimensional (1d) equation,double power series expansion technique stress relaxation initial carrier density

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Numerical simulation of flow past a square cylinder with a circular bar upstream and a splitter plate downstream

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Journal of Hydrodynamics 2019年第5期31卷 949-964页

作者： Yuan ma MMRashidi Zhi-g.ng.Yang Shang.ai Automotive Wind Tunnel Center Tongji UniversityShanghai 201804China Shang.ai Key Laboratory of Vehicle Aerodynamics and Vehicle Thermal manag.ment Systems Shanghai 201804China department o f Civil Eng.neering School of EngineeringUniversity of BirminghamBirminghamUK

A numerical investig.tion of flow past a square cylinder with a circular bar upstream and a splitter plate downstream is carried out in this paper by lattice Boltzmann method(LBM).The combination of the three obstacles and LBM is the main novelty of the present *** flow patterns are analyzed by a uniform flow of Reynolds number 100 based on the side leng.h of the square cylinder,*** simulations are performed in the rang. of 1≤ds/d≤5,0≤g.d≤7 and 1≤L/d≤6,where ds,g.and L are the center-to center distance,surface-to-surface distance and the splitter plate leng.h,*** flow patterns are observed in the present *** maximum percentag. reduction in mean drag.coefficient is 68.76%at(ds,g.l)=(2.5,0,3)which is in pattern *** vortex shedding.from the square cylinder and the circular bar can be completely suppressed in pattern *** small distance between the square cylinder and the splitter plate plays a more vital role in suppression of vortex shedding.as compared with larg. distance and leng.h.

关键词： Square cylinder lattice Boltzmann method(LBM) reduction of drag forces vortex shedding control circular bar splitter plate

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