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Provenance of Conglomerate and Sandstone from Early Permian Shoushangou Formation in Xi Ujimqin,Inner Mongolia:Implications for Understanding Paleo-Asian Ocean Subduction

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 10-31页

作者： ZHANG Yingli GUO Xianqing ma Shouxian MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China Chinese Academy of Geological Sciences Beijing 100037China

During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin ***,the closure time of the PAO is still under ***,to identify the origin of the PAO,the geochemistry and U-Pb age of zircons were analyzed for the extra-large deep marine,polymict clastic boulders and sandstones in the Shoushangou Formation within the *** analyses revealed magmatic activity and tectonic *** conglomerates include megaclasts of granite(298.8±9.1 ma)and granodiorite porphyry(297.1±3.1 ma),which were deposited by muddy debris *** of this study demonstrated that the boulders of granitoids have the geochemistry of typical I-type granite,characterized by low Zr+Nb+Ce+Y and low ga/Al *** granitoid boulders were formed in island arc setting,indicating the presence of arc magmatism in the area that is composed of the Late Carboniferous to Early Permian subduction-related granitoid in southern Xi *** diagrams for determining sedimentary provenance using major and trace elements indicate that Shoushangou sediments originated from continental island arc-related felsic *** zircon U-Pb age cluster of 330–280 ma was obtained,indicating input from granite,ophiolite,Xilin Gol complex,and Carboniferous sources to the *** basin was geographically developed behind the arc during the Early Permian period because the outcropped intrusive rocks in the Late Carboniferous to Early Permian form a volcanic *** comprehensive analyses of source areas suggest that Shoushangou sediments developed in a backarc basin in response to the northward subduction of the *** backarc basin and intrusive rocks,in addition to previously published Late Carboniferous to Early Permian magmatic rocks of arc unit in Xilin Gol,confirm the presence of an Early Permian trencharc-basin system in the region,r

关键词： provenance analysis backarc basin Shoushangou Formation Early Permian Central Asian Orogenic Belt

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A review of vehicle detection methods based on computer vision

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Journal of Intelligent and Connected Vehicles

Journal of Intelligent and Connected Vehicles 2024年第1期7卷 1-18页

作者： Changxi ma Fansong Xue School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory of Railway Industry on Plateau Railway Transportation Intelligent management and Control Lanzhou 730070China

With the increasing number of vehicles,there has been an unprecedented pressure on the operation and maintenance of intelligent transportation systems and transportation *** order to achieve faster and more accurate identification of traffic vehicles,computer vision and deep learning technology play a vital role and have made significant *** study summarizes the current research status,latest findings,and future development trends of traditional detection algorithms and deep learning-based detection *** the detection algorithms based on deep learning,this study focuses on the representative convolutional neural network ***,it examines the two-stage and one-stage detection algorithms,which have been extensively utilized in the field of intelligent transportation *** to traditional detection algorithms,deep learning-based detection algorithms can achieve higher accuracy and *** single-stage detection algorithm is more efficient for real-time detection,while the two-stage detection algorithm is more accurate than the single-stage detection *** the follow-up research,it is important to consider the balance between detection efficiency and detection ***,vehicle missed detection and false detection in complex scenes,such as bad weather and vehicle overlap,should be taken into *** will ensure better application of the research findings in engineering practice.

关键词： intelligent transportation system computer vision deep learning vehicle detection object detection algorithm

A review of research on urban parking prediction

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 700-720页

作者： Changxi ma Xiaoting Huang Jiangchen Li School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The rapid growth of urban traffic has intensified daily congestion,affecting both traffic flow and *** parking prediction plays a vital role in effectively managing limited parking resources and is essential for the successful implementation of advanced intelligent *** an effort to comprehensively assess the latest developments in parking prediction,we curated a dataset of 639 articles spanning from 2010 to the present,using the Scopus ***,we performed a bibliometric analysis utilizing VOSviewer *** findings not only illuminate emerging trends within the parking prediction field but also provide strategic guidance for its ***,we categorized advancements in three focal areas:behavior prediction,demand prediction,and parking space prediction.A comprehensive overview of the present research status and future directions was then *** findings underscore the substantial progress achieved in current parking prediction models,achieved through diverse avenues like multi-source data integration,multi-variable feature extraction,nonlinear relationship modeling,deep learning techniques application,and ensemble model *** innovative endeavors have not only pushed the theoretical boundaries of parking prediction but also significantly heightened the precision and applicability of predictive models in practical *** research should explore avenues such as processing unstructured parking datasets,developing predictive models for small-scale data,mitigating noise interference in parking data,and harnessing potent platform fusion *** study's significance transcends guiding and catalyzing advancement in academic and practical domains;it holds paramount relevance across academic research,technological innovation,decision-making support,business applications,and policy formulation.

关键词： Parking prediction machine learning Smart parking Deep learning

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Control of aluminum distribution in ZSM-5 zeolite for enhancement of its catalytic performance for propane aromatization

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 15-24页

作者： Zhao ma Dezhi Shi Sen Wang Mei Dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Regulation of aluminum distribution in zeolite framework is an effective method for improving its catalytic performance for propane ***,we found that recrystallization and post-realuminization of ZSM-5 cannot only create hollow structures to enhance the diffusion ability,but also adjust the content and position of paired aluminum species in its *** characterizations results confirmed that increase of paired aluminum content and inducement of more aluminum atoms sited in the intersection cavity are beneficial to the formation of aromatic products in propane *** a result,the hollow-structured ZSM-5 zeolite with more paired aluminum(H-200-hollow)showed higher propane conversion and aromatics selectivity than other samples at the same *** catalytic performance of H-200-hollow can be further improved by ion-exchanging with a small amount of ga(III)*** propane conversion and aromatics selectivity of ga-200-hollow reached as high as 95%and 70%,respectively,at 540°C and 1 atm.

关键词： propane aromatization zeolite aluminum distribution recrystallization and post-realuminization

Insight into the Role and Evidence of Oxygen Vacancies in Porous Single-Crystalline Oxide to Enhance Catalytic Activity and Durability

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Research 2024年第2期2023卷 675-683页

作者： Lingting Ye Jiaming ma Jie Zhang Wen Yin Yuanguang Xia Kui Xie Key Laboratory of Optoelectronic materials Chemistry and Physics Fujan Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Advanced Energy Science and Technology Guangdong Laboratory 29 Sanxin North RoadHuizhouGuangdong 116023China Spallation Neutron Source Science Center DongguanGuangdong 523803China

Introducing and stabilizing oxygen vacancies in oxide catalysts is considered to be a promising strategy for improving catalytic activity and ***,we quantitatively create oxygen vacancies in the lattice of porous single-crystallineβ-ga_(2)O_(3)monoliths by reduction treatments and stabilize them through the long-range ordering of crystal lattice to enhance catalytic activity and *** combination analysis of time-of-flight neutron powder diffraction and extended x-ray absorption fine structure discloses that the preferential generation of oxygen vacancy tends to occur at the site of tetrahedral coordination oxygen ions(O_(Ⅲ)sites),which contributes to the formation of unsaturated ga-O coordination in the monoclinic *** oxygen vacancies are randomly distributed in lattice even though some of them are present in the form of domain defect in the PSC ga_(2)O_(3)monoliths after the reduction *** number of oxygen vacancies in the reduced monoliths gives 2.32×10^(13),2.87×10^(13),and 3.45×10^(13)mg^(-1)for the ga_(2)O_(2.952),ga_(2)O_(2.895),and ga_(2)O_(2.880),*** therefore demonstrate the exceptionally high C_(2)H_(4)selectivity of~100%at the C_(2)H_(6)conversion of~37%for nonoxidative dehydrogenation of C_(2)H_(6)to C_(2)H_(4).We further demonstrate the excellent durability even at 620℃for 240 h of continuous operation.

关键词： durability coordination Oxygen

Achieving strength-ductility synergy in novel paramagnetic Fe-based medium-entropy alloys through deep cryogenic deformation

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Rare Metals 2024年第9期43卷 4493-4507页

作者： Hu-Wen ma Yan-Chun Zhao Li Feng Tian-Zeng Liu Zhi-Qi Yu Bo Jin Wang-Chun Duan Peter K.Liaw Dong ma State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou 730050China Wenzhou Pump and Valve Engineering Research Institute Lanzhou University of TechnologyWenzhou 325105China Iron and Steel Research Institute Jiuquan Iron and Steel CorporationJiayuguan 735100China Lanzhou Resources and Environment Voc-Tech University Lanzhou 730123China Department of materials Science and Engineering The University of TennesseeKnoxvilleTN 37996-2200USA Neutron Science Center Songshan Lake Materials LaboratoryDongguan 523808China

Cryogenic pre-deformation treatment has been widely used to effectively improve the comprehensive mechanical properties of steels and novel ***,the dislocation evolution and phase transformation induced by different degrees of deep cryogenic deformation are not yet fully *** this study,the effects of multiple cryogenic pre-treatments on the mechanical properties and deformation mechanisms of a paramagnetic Fe_(63.3)Mn_(14-)Si_(9.1)Cr_(9.8)C_(3.8)medium-entropy alloy(MEA)were investigated,leading to the discovery of a pretreated MEA that exhibits exceptional mechanical properties,including a fracture strength of 3.0 GPa,plastic strain of 26.1%and work-hardening index of *** addition,X-ray diffraction(XRD)and transmission electron microscopy(TEM)analyses revealed that multiple cryogenic pre-deformation treatments significantly increased the dislocation density of the MEA(from 9×10^(15)to 4×10^(16)m^(-2)after three pretreatments),along with a transition in the dislocation type from predominantly edge dislocations to mixed dislocations(including screw-and edge-type dislocations).Notably,this pretreated MEA retained its paramagnetic properties(μ_(r)mately four(i.e.,from 9.7 to2.6 m J·m^(-2)),thereby activating the synergistic effects of transformation-induced plasticity,twinning-induced plasticity and dislocation strengthening *** synergistic effects lead to simultaneous strength and ductility enhancement of the MEA.

关键词： Deep cryogenic transformation Iron-based medium-entropy alloys Dislocation evolution Phase transformation Stacking fault energy

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Double random number encryption blind watermarking technique based on DWT-DCT domain

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Optoelectronics Letters 2024年第10期20卷 614-622页

作者： WANG Chenglong ma Yi WANG Xia National Engineering Research Center for Technology and Equipment of Environmental Deposition Lanzhou Jiaotong University Key Laboratory of Opto-Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University

Blind watermarking plays a significant role in copyright protection and information hiding. To enhance the security of watermark image information, a dual encryption method is proposed, which combines block shuffling with Logistic chaos encryption using two sets of random numbers as keys. This dual encryption technique is applied to blind watermark images, utilizing a combination of discrete wavelet transform(DWT) and discrete cosine transform(DCT) as the embedding method. First, the watermark image is divided into small blocks, which are shuffled and rearranged using one set of random numbers as the key, while recording the shuffling sequence of block positions. Subsequently, the shuffled blocks are reassembled into an image, and another set of random numbers is used as the key for Logistic chaos encryption, rendering the watermark image chaotically invisible. Then, a double DWT is applied to the carrier image, followed by a DCT, allowing the encrypted watermark image to be embedded. This achieves the concealment of the blind watermark. Experimental results demonstrate that this method exhibits robustness, excellent invisibility, and secrecy.

关键词： A

Evaluation of Antibiotic Prescribing in the Pediatric Department of gabriel TouréTeaching Hospital, Bamako, mali

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Open Journal of Pediatrics 2024年第3期14卷 645-656页

作者： Pierre Togo Hawa Konaré mariam maïga Karamoko Sacko Djénéba Konaté Abdoul Karim Doumbia Adama Dembélé Oumar Coulibaly Aminata Sangaré Mohamed Elmouloud Cissé Fousseyni Traoré Belco maïga Ibrahim Ahamadou Aminata Doumbia Lala N’Drany Sidibé Amadou Touré Yacouba Aba Coulibaly Kalirou Traoré Tati Simaga Souleymane Sagara Leyla Bagna maïga Bory Traoré Abdoul Aziz Diakité Fatoumata Dicko mariam Sylla Sounkalo Dao Boubacar Togo Paediatric Department Gabriel Tour&#233 Teaching Hospital Bamako Mali Pediatric Department Distric VI Reference Health Center Bamako Mali Infectious Diseases Department Point G Teaching Hospital Bamako Mali

Objectives: The main objective was to evaluate antibiotic prescribing in the Department of Pediatrics at gabriel Touré teaching hospital. Methods: This was a prospective descriptive study conducted from September 1 to November 31, 2018, in the Department of Pediatrics at gabriel Touré teaching hospital. All children aged 0 to 15 years hospitalized for any pathology during the study period and having received at least one antibiotic had been included. Results: We collected 445 children’s records out of 1032 admissions during the study period, representing a hospital frequency of 43.1%. The sex ratio was 1.3%. The 2 - 5 age group accounted for 48.1%. Fever was the reason for consultation in 45.6% of cases. Patients’ general condition was altered in 60% of cases. The fathers were blue-collar workers in 65.4% and the mothers housewives in 85%, and had no education in 42.9% and 64.5% respectively. Hepatomegaly was present in 18.2%, splenomegaly in 9.6% and peripheral adenopathy in 3.1%. The site of infection was pulmonary in 37.6% and ENT in 9.2%. Bacterial infection was assumed on admission in 54% of cases, and meningitis in 57.7%. The discharge diagnosis was malaria in 54.6%, severe acute malnutrition in 18.6% and meningitis in 6.7%. The death rate was 3.8%. Neutrophilic leukocytosis was present in 47.3% of patients. CRP was positive in 85% of patients. Blood cultures taken in 27.6% of patients were positive in 5. CSF analysis in 30% of patients showed elevated leukocytes in 6.5%. No cultures were positive. Antibiotic prescription was justified by infectious hypotheses in 43.1% of patients. β-lactam antibiotics were prescribed in 98.6%. Antibiotic therapy was not adapted to national/international recommendations in 68.3% of cases, and was not justified in 16.3% of cases on D5 of hospitalization. Conclusion: Antibiotic use was justified in more than half of patients, but remained inadequate in almost two-thirds of cases, in line with national and international recommend

关键词： Antibiotic Prescription Hospitalization Child

Facile fabrication of CdIn_(2)S_(4)/TiO_(2)heterojunction for enhanced solar light efficient CO_(2)reduction

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 101-112页

作者： Xiaoyu ma Longlong Wang Houde She Yu Zhou Lei Wang Jingwei Huang Qizhao Wang College of Chemistry and Chemical Engineering Northwest Normal UniversityLanzhou 730070China School of Environment Science and Engineering Chang’an UniversityXi’an 710064China

Photocatalytic CO_(2)reduction is a promising solution to simultaneously provide renewable chemical fuels and address the greenhouse ***,designing practical photocatalysts with advanced architectures remains ***,we report the preparation of a novel CdIn_(2)S_(4)/TiO_(2)binary heterojunction via an in situ solvothermal approach,which exhibits superior photocatalytic activity for sunlight-driven CO_(2)*** CdIn_(2)S_(4)/TiO_(2)composites exhibit significantly enhanced photocatalytic performance for CO_(2)reduction compared to unmodified TiO_(2).Among them,the 3%CdIn_(2)S_(4)/TiO_(2)composite has optimal CO and CH_(4) evolution rates of 18.32 and 1.03μmol·g–1·h–1,*** yield of CO is 4.7 times higher than that of pristine TiO_(2).This improved photocatalytic activity of the CdIn_(2)S_(4)/TiO_(2)heterostructure can be attributed to its large surface area,extended light absorption range and high separation efficiency of photogenerated electron-hole pairs,which are supported by the results of photoluminescence spectroscopy and the photoelectrochemical ***,the photocatalytic mechanism based on the binary CdIn_(2)S_(4)/TiO_(2)heterojunction is proposed and separation process of photogenerated electron-hole pairs is *** brief,we aim to provide insights into the application of TiO_(2)in energy conversion processes through the construction of heterogeneous junctions.

关键词： TiiO_(2) CdIn_(2)S_(4) heterojunction photocatalytic CiO_(2)reduction