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Automated registration of wide-baseline point clouds in forests using discrete overlap search

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Forest ecosystems 2022年第6期9卷 852-877页

作者： Onni Pohjavirta Xinlian Liang Yunsheng Wang Antero Kukko Jiri Pyorala eric Hyyppa Xiaowei Yu harri Kaartinen Juha Hyyppa Department of Remote Sensing and Photogrammetry Finnish Geospatial Research InstituteVuorimiehentie 5Espoo02150Finland The State Key Laboratory of Information engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan430070China Department of Forest Sciences University of HelsinkiHelsinkiFI-00014Finland Department of Geography and Geology University of TurkuTurkuFI-20500Finland

Forest is one of the most challenging environments to be recorded in a three-dimensional(3D)digitized geometrical representation,because of the size and the complexity of the environment and the data-acquisition constraints brought by on-site *** studies have indicated that the data-acquisition pattern can have more influence on the registration results than other *** practice,the ideal short-baseline observations,i.e.,the dense collection mode,is rarely feasible,considering the low accessibility in forest environments and the commonly limited labor and time *** wide-baseline observations that cover a forest site using a few folds less observations than short-baseline observations,are therefore more preferable and commonly ***,the wide-baseline approach is more challenging for data registration since it typically lacks the required sufficient overlaps between *** now,a robust automated registration solution that is independent of special hardware requirements has still been *** is,the registration accuracy is still far from the required level,and the information extractable from the merged point cloud using automated registration could not match that from the merged point cloud using manual *** paper proposes a discrete overlap search(DOS)method to find correspondences in the point clouds to solve the low-overlap problem in the wide-baseline point *** proposed automatic method uses potential correspondences from both original data and selected feature points to reconstruct rough observation geometries without external knowledge and to retrieve precise registration parameters at *** extensive experiment was carried out with 24 forest datasets of different conditions categorized in three difficulty *** performance of the proposed method was evaluated using various accuracy criteria,as well as based on data acquired from different hardware,platforms,viewing persp

关键词： Close-range sensing Forest Registration Point cloud Wide-baseline Terrestrial laser scanning Unmanned aerial vehicle Drone In situ Discrete overlap search

Pancreatic neuroendocrine tumors: biology, diagnosis, and treatment

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Chinese Journal of Cancer 2013年第6期32卷 312-324页

作者： Cynthia ro Wanxing Chai Victoria e.Yu Run Yu Cedars-Sinai Medical Center Los Angeles CA 90048 USA

Pancreatic neuroendocrine tumors (PNeTs), a group of endocrine tumors arising in the pancreas, are among the most common neuroendocrine tumors. The genetic causes of familial and sporadic PNeTs are somewhat understood, but their molecular pathogenesis remains unknown. Most PNeTs are indolent but have malignant potential. The biological behavior of an individual PNeT is unpredictable; higher tumor grade, lymph node and liver metastasis, and larger tumor size generally indicate a less favorable prognosis. endocrine testing, imaging, and histological evidence are necessary to accurately diagnose PNeTs. A 4-pronged aggressive treatment approach consisting of surgery, locoregional therapy, systemic therapy, and complication control has become popular in academic centers around the world. The optimal application of the multiple systemic therapeutic modalities is under development; efficacy, safety, availability, and cost should be considered when treating a specific patient. The clinical presentation, diagnosis, and treatment of specific types of PNeTs and familial PNeT syndromes, including the novel Mahvash disease, are summarized.

关键词：肿瘤生物学神经内分泌全身治疗胰腺诊断生物学行为发病机制学术中心

Survival of transplanted nests of the red wood ant Formica aquilonia （Hymenoptera： Formicidae）： The effects of intraspecific competition and forest clear-cutting

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Insect Science 2014年第4期21卷 486-492页

作者： Jouni Sorvari esa Huhta harri Hakkarainen 1 Section of ecology Department of Biology FI-20014 University of Turku Finland Department of environmental Science University of Eastern Finland P.O. Box 1627 FI-70211 Kuopio Finland Finnish Forest Research Institute Rovaniemi Research Unit P.O. Box 16 FI-96301 Rovaniemi Finland

The fitness and survival of ant colonies depend on the resources near their nests. These resources may be limited due to poor habitat quality or by intra- and interspecific competitions, which in extreme cases may cause the ant colony to perish. We tested the effect of intraspecific competition and habitat degradation （forest clear-cutting） on colony survival by transplanting 26 nests of the red wood ant （Formica aquilonia Yarrow, 1955） in 26 different forest areas that contained 0-11 conspecific alien nests per hectare. F. aquilonia is highly dependent on canopy-dwelling aphids, thus the removal of trees should cause food limitation. During the course of the 4-year experiment, 9 of the forests were partially clear- cut. We found that while forest clear-cutting significantly decreased the colonies＇ survival, intraspecific competition did not. As a highly polygynous and polydomous species, e aquilonia seems to tolerate the presence of alien conspecific colonies to a certain extent.

关键词： colony survival habitat degradation polydomy red wood ants relocationexperiment

Solvent-free fabrication of broadband WS2 photodetectors on paper

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Opto-electronic Advances 2023年第3期6卷 1-11页

作者： Wenliang Zhang Onur Çakıroğlu Abdullah Al-enizi Ayman Nafady Xuetao Gan Xiaohua Ma Sruthi Kuriakose Yong Xie Andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de Madrid(ICMM-CSIC)Madrid E-28049Spain Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710129China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710071China

Paper-based devices have attracted extensive attention due to the growing demand for disposable flexible ***,we integrate semiconducting devices on cellulose paper substrate through a simple abrasion technique that yields high-performance photodetectors.A solvent-free WS_(2) film deposited on paper favors an effective electron-hole separation and hampers *** as-prepared paper-based WS2 photodetectors exhibit a sensitive photoresponse over a wide spectral range spanning from ultraviolet(365 nm)to near-infrared(940 nm).Their responsivity value reaches up to~270 mA W^(−1) at 35 V under a power density of 35 mW cm^(−2).A high performance photodetector was achieved by controlling the environmental exposure as the ambient oxygen molecules were found to decrease the photoresponse and stability of the WS_(2) ***,we have built a spectrometer using such a paperbased WS_(2) device as the photodetecting component to illustrate its potential *** present work could promote the development of cost-effective disposable photodetection devices.

关键词： paper electronics photodetector van der Waals materials solvent-free deposition tungsten disulfide

Development of the modified k-ε turbulence model of power-law fluid for engineering applications

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Science China(Technological Sciences) 2012年第1期55卷 276-284页

作者： ro Kyoungchul RYOU HongSun Department of Mechanical engineering Chung-Ang University

In the present study,a high Reynolds number version of a turbulence model was proposed by using drag reduction to analyze the turbulent flows of power-law fluid for engineering *** order to determine the model constants in the constitu-tive equation,numerical simulation was conducted under the same conditions that were applied to obtain the experiment re-sults and previous turbulence *** validation of the modified turbulence model,numerical simulations were performed for power-law fluids of different *** results of the modified k-ε turbulence model showed better agreement with the experimental results than those of the standard k-ε turbulence *** addition,computation time and computer resource of the modified k-ε turbulence model were reduced by about one third as compared to the low Reynolds number model for power-law fluids.

关键词： power-law fluid turbulent flow drag reduction turbulence model computational fluid dynamics(CFD)

Research on arbuscular mycorrhizae in Cuba:a historical review and future perspectives

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Studies in Fungi 2021年第1期6卷 240-262页

作者： Furrazola e Torres-Arias Y Ojeda-Quintana L Fors ro rodrígue.-rodrígue. R Ley-Rivas JF Mena A González-González S Berbara RLL Queiroz MB Hamel C Goto BT Instituto de ecología y Sistemática CITMA Carretera Varona 11835 e/Oriente y LinderoLa Havana 19CalabazarBoyerosLa HavanaCuba CUM Cumanayagua Universidad de Cienfuegos“Carlos R.Rodríguez”CienfuegosCuba Universidade Federal Rural do Rio de Janeiro Instituto de AgronomiaSeropedicaRJBrazil Instituto Nacional de Ciencias Agropecuarias(INCA) Gaveta Postal 1San Joséde las LajasMayabequeCuba Universidad de Temuco Chile Programa de Pós-graduação em Sistemática e evolução CBUniversidade Federal do Rio Grande do NorteCampus Universitário59072-970NatalRNBrazil Quebec Research and Development Centre Agriculture and Agri-Food Canada2560 Hochelaga BlvdQuebec CityQCCanada G1V 2J3

This review presents the development of researches on arbuscular mycorrhizae(AM)conducted in Cuba,a tropical Caribbean island rich in *** key findings from this work are highlighted and presented as a stepping stone for future *** research has contributed to understand the diversity and functionality of AM in several tropical ecosystems,mainly evergreen forests,agroecosystems,sand dunes and *** were conducted in 10 out of 16 provinces reported 79 AM species,representing 25%of the known species *** researchers have a great deal of expertise in Glomeromycota taxonomy and have described 11 new species,of which six were not reported elsewhere in the ***,important studies conducted in Cuba have shed light on the mycotrophic plants,the role of AM in forest ecosystems,and their use in crop *** contribution of AM to ecosystem processes is a priority line of *** and multidisciplinary researches are necessary to define the role of AM symbioses and improve biogeochemical *** created Cuban Mycorrhizal Research Network will help to coordinate validation campaigns for various biofertilizers with training courses for Cuban farmers to disseminate the key results on *** the challenges for Cuban mycorrhizologists,molecular(genomic)techniques,stable isotopes and nuclear magnetic resonance should also be included as priority lines of research in the future.

关键词： Arbuscular mycorrhizal fungi diversity ecosystems mycorrhizal research symbiotic associations

均相和非均相催化微藻脂质提取和酯交换制备生物燃料的研究进展

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Chinese Journal of Catalysis 2024年第4期59卷 97-117页

作者： Vinoth Kumar Ponnumsamy Hussein e.Al-Hazmi Sutha Shobana Jeyaprakash Dharmaraja Dipak Ashok Jadhav Rajesh Banu J Grzegorz Piechota Bartłomiej Igliński Vinod Kumar Amit Bhatnagar Kyu-Jung Chae Gopalakrishnan Kumar 高雄医科大学药物与应用化学系环境医学研究中心中国台湾高雄高雄医科大学医学研究部中国台湾高雄格但斯克理工大学土木与环境工程学院波兰纳鲁特维察格但斯克范朗大学工程与技术学院建筑绿色技术与可持续发展研究组越南胡志明市工程技术学院科学与人文系化学部印度泰米尔纳德邦韩国海洋大学海洋科学与工程学院环境工程系韩国釜山泰米尔纳德邦中央大学生命科学系印度泰米尔纳德邦 GPCHeM沼气研究与分析实验室波兰尼古拉斯哥白尼大学化学系波兰克兰菲尔德大学水与能源学院英国拉彭兰塔工业大学工程科学学院分离科学系芬兰韩国海洋大学海洋可再生能源工程专业韩国釜山延世大学土木与环境工程学院韩国首尔斯塔万格大学科学技术学院化学、生物科学与环境工程研究所挪威斯塔万格

随着化石燃料燃烧导致的二氧化碳排放不断加剧气候变化,且化石燃料储量日益减少,寻求可再生能源已成为一项紧迫的任务.其中,藻类衍生可持续燃料因具有成本优势和可运输性,在解决全球能源危机方面展现出广阔前景,备受关注.利用化学转化... 详细信息

随着化石燃料燃烧导致的二氧化碳排放不断加剧气候变化,且化石燃料储量日益减少,寻求可再生能源已成为一项紧迫的任务.其中,藻类衍生可持续燃料因具有成本优势和可运输性,在解决全球能源危机方面展现出广阔前景,备受关注.利用化学转化技术从微藻中提取脂质,并通过酯交换反应可以将其转化为脂肪酸甲酯,是生产绿色生物燃料的有效途径.这一过程涉及游离脂肪酸、磷脂和甘油三酯的提取,并且生产过程能耗低,成为满足日益增长的能源需求的一种理想解决方案.本文综述了微藻脂质提取和酯交换制备生物燃料的相关研究进展.首先,介绍了微藻脂质的提取方法,包括溶剂提取法、索氏提取法、布利格和戴耶法、超临界二氧化碳提取以及离子液体溶剂法等,并分析了各方法的优缺点.随后,重点阐述了酯交换技术在微藻脂质转化中的应用,包括酸碱催化、酶催化以及原位酯交换反应等,并探讨了这些技术的反应机理、催化剂选择、反应器设计以及生物油生产工艺等方面的研究进展.通过综述上述研究进展,为微藻脂质的生产和应用提供了理论指导.研究表明,通过优化催化剂种类、反应条件以及提取方法,可以有效提高微藻脂质的转化效率和生物油品质.同时,本文也指出了当前微藻脂质生产中面临的挑战,如微藻栽培和生长条件优化、高效转化技术的开发等.随着可持续能源日益受到重视,微藻脂质作为一种可再生能源具有巨大的发展潜力.未来研究应进一步关注微藻的规模化栽培、生长条件优化以及高效转化技术的研发,以提高微藻脂质的产量和品质.同时,应进一步推动和实现微藻生物燃料的实际应用,从而为应对气候变化和能源危机提供有效的解决方案.

关键词：微藻脂质提取酯交换催化酶催化原位技术

When horsetails became giants

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Chinese Science Bulletin 2012年第18期57卷 2285-2288页

作者： FeNG Zhuo ZIeroLD Thofid roβLeR ronny Museum fur Naturkunde ChemnitzMoritzstraβe 2009111Germany Yunnan Key Laboratory for Palaeobiology Yunnan UniversityKunming 650091China

Horsetails arose in the Late Devonian,evolved a greater diversity and forming fast growing bamboo-like thickets in the Carboniferous lowland swamp forest ***,the diversity of this group drastically declined during the Permian while the climate became more dynamic and *** only a single surviving genus exists,the herbaceous *** we report an exceptional large horsetail tree from the early Permian Petrified Forest of *** fossil horsetail tree is assigned to Arthropitys bistriata (Cotta) *** is 15 m high and over 25 cm in diameter,with thick wood and at least 3 orders of woody branching system formed a big canopy,and is morphologically very comparable with the living woody higher *** suggests that the plasticity mechanism of Permian calamitaleans enabled novel growth strategies when they competed with the rising gymnosperms during the environmental changes.

关键词：木贼森林生态系统巨人早二叠世分支系统植物形态裸子植物环境变化

UNILATeRAL eIGeNVALUe ProBLeMS FOR NONLINeARLY eLASTIC PLATeS: AN APProACH VIA PSeUDO-MONOTONe OPeRATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 147-152页

作者： LILIANA GRATIe(Faculty of engineering-Braila, Dunarea de Jos University of Galati, Calarasilor 29, Braila 6100, romania.) e-mail: gratie@starnets.ro Faculty of engineering-Braila Dunarea de Jos University of Galati Calea Calarasilor 29 Braila 6100 Romania

This paper considers a class of variational inequalities that model the buckling of a von Karman plate clamped on a part of its boundary and lying on a fiat rigid support. The existence and bifurcation results of D. Goeleven, V. H. Nguyen and M. Thera[6] rely on the Leray- Schauder degree. Using the topological degree for pseudo-monotone operators of type (S+), the author establishes a more general existence result for such unilateral eigenvalue problems.

关键词：单向特征值问题伪单调算子变分不等式拓扑度