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Acta Oceanologica Sinica 2011年第3期30卷 63-75页

作者： HE Gaowen MA Weilin SONG Chengbing YANG Shengxiong ZHU Benduo YAO Huiqiang JIANG Xunxiong CHENG Yongshou Guangzhou Marine Geological Survey Guangzhou 510075 China Second Institute of Oceanography State Ocean Administration Hangzhou 310012 China China Ocean Mineral resources R ＆ D Association Beijing 100860 China Beijing General Research Institute of Mining ＆ Metallurgy Beijing 100070 China National Marine information center Tianjin 300171 China

In 2001, the International Seabed Authority （ISBA） initiated the consideration relating to the Regulations for Prospecting and Exploration for Hydrothermal Polymetallic Sulphides and Cobalt-rich Ferromanganese Crusts in the Area at its 7th session. Since then, the consideration of the Regulations has been mainly focused on the size of areas to be allocated for exploration and exploitation of the crusts. This paper, based on the investigation data and the analysis of the distribution characteristics of the crusts, suggests a model for determining the size of areas for exploration and exploitation of the crusts, taking into account various factors such as production scale, crust thickness and grade, mineable area proportion, recovery efficiency, exploration venture, and so on. Through the modeling, the paper suggests that the exploration area （the area covered by each application for approval of a plan of work for exploration of cobalt-rich crusts） shall be 4 856 km2 and the exploitation area （the mine site area） shall be 1 214 km2, for 20 years of 1 million wet tonnes annual production.

关键词： cobalt-rich ferromanganese crusts exploration and exploitation area seamounts regulation on exploration

A survey of photon mapping state-of-the-art research and future challenges

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Frontiers of information Technology & Electronic Engineering 2016年第3期17卷 185-199页

作者： Chun-meng KANG Lu WANG Yan-ning XU Xiang-xu MENG Department of Computer Science and Technology Shandong University Engineering Research center of Digital Media Technology Ministry of Education

Global illumination is the core part of photo-realistic rendering. The photon mapping algorithm is an effective method for computing global illumination with its obvious advantage of caustic and color bleeding rendering. It is an active research field that has been developed over the past two decades. The deficiency of precise details and efficient rendering are still the main challenges of photon mapping. This report reviews recent work and classifies it into a set of categories including radiance estimation, photon relaxation, photon tracing, progressive photon mapping, and parallel methods. The goals of our report are giving readers an overall introduction to photon mapping and motivating further research to address the limitations of existing methods.

关键词： Global illumination Photon mapping Radiance estimation Photon relaxation Progressive photon mapping

Rapid flood inundation mapping by differencing water indices from pre-and post-flood Landsat images

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Frontiers of Earth Science 2021年第1期15卷 1-11页

作者： Ramesh SIVANPILLAI Kevin M.JACOBS Chloe M.MATTILIO Ela V.PISKORSKI Wyoming Geographic information Science center University of WyomingLaramieWY 82071USA Department of Ecosystem Science&Management University of WyomingLaramieWY 82071USA Haub School of Environment&Natural resources University of WyomingLaramieWY 82071USA Department of Plant Sciences University of WyomingLaramieWY 82071USA

Following flooding disasters,satellite images provide valuable information required for generating flood inundation *** or optical imagery can be used for generating flood maps when the inundated areas are not covered by *** propose a rapid mapping method for identifying inundated areas based on the increase in the water index value between the pre-and post-flood satellite *** of the Normalized Difference water Index(NDWI)and Modified NDWI(MNDWI)will be higher in the post-flood image for flooded areas compared to the pre-flood *** on a threshold value,pixels corresponding to the flooded areas can be separated from non-flooded *** maps derived from differencing MNDWI values accurately captured the flooded *** the output image will be influenced by the choice of the pre-flood image,hence analysts have to avoid selecting pre-flood images acquired in drought or earlier flood *** the inundation maps generated using this method have to be overlaid on the post-flood satellite image in order to orient personnel to landscape *** of the proposed technique are that flood impacted areas can be identified rapidly,and that the pre-existing water bodies can be excluded from the inundation *** pairs of other satellite data,several maps can be generated within a single flood which would enable emergency response agencies to focus on newly flooded areas.

关键词： Rapid Flood Mapping(RFM) inundation maps Satellite data NDWI MNDWI

Scatter-hoarding rodent foraging preference on nutrient content is mediated by seed size

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Current Zoology 2020年第4期66卷 445-446页

作者： Bo WANG Xiaolan YANG School of resources and Environmental Engineering Anhui UniversityHefei230601China center for integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla666303China

Sced dispersal and predation by satterhoarding rodents play an im-portant role in seedling regeneration,community structure and com-position,and species coexistence(Vander Wall 2010;Zhang et al.2016).Rodents generally exhibit seed species preference during their scatter-hoarding behavioral processes Xiao et al.2006;Gong et al.2015;Zhang et al.2016),and seed traits are a key factor in explain-ing rodent foraging preference(Wang and Chen 2009;Vander Wall 2010;Zhang et al.2016).Numerous studies have explored how the diversity of seed traits influences rodent foraging behavior but have shown inconsistent results(Blate et al 1998;Moles et al.2003;Xiao et al.2006;Wang and Chen 2009).

关键词： seedling content inconsistent

Role of surface roughness in the magnesite flotation and its mechanism

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Particuology 2022年第3期20卷 63-70页

作者： Zhanglei Zhu Yafeng Fu Wanzhong Yin Haoran Sun Keqiang Chen Yuan Tang Bin Yang School of resources and Civil Engineering Northeastern UniversityShenyang 110819China Ansteel Beijing Research Institute CO. LTD.Beijing 102200China Genetic Mineral Processing Research center Northeastern UniversityShenyang 110819China

Surface roughness has a significant influence on mineral *** assisting effect of surface roughness on minerals flotation is extensively investigated from its physical properties(e.g.,the existing form of asperity and its size),however,the associated effect on mineral flotation based on the differences in surface chemical property caused by surface roughness has been rarely *** such a question in mind,in this study,we investigated the flotation recoveries of two batches of magnesite particles with varying degree of surface roughness produced by two different mills,and associated the flotation performances to their surface chemical properties(amount of adsorption sites for the collector)via a series of detections,including Scanning Electron Microscope-Energy Dispersive Spectrometry(SEM-EDS)observations,X-ray photoelectron spectroscopy(XPS)analysis,adsorption capacity tests,and contact angle ***,we concluded that rougher magnesite particles could provide more active sites(Mg^(2+))for a larger capacity of sodium oleate(NaOL),thereby improving the hydrophobicity and floatability.

关键词： Surface roughness Active adsorption site Collector adsorption capacity Flotation performance

Prediction of Neural Tube Defect Using Support Vector Machine

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Biomedical and Environmental Sciences 2010年第3期23卷 167-172页

作者： JIN-FENG WANG XIN LIU YI-LAN LIAO HONG-YAN CHEN WAN-XIN LI XIAO-YING ZHENG State key Laboratory of resources and Environmental information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute for Sustainable water Integrated Management & Ecosystem Research (SWIMMER) University of Liverpool Liverpool L69 3GP UK City University of Hong Kong Tsinghua Graduate School at Shenzhen 518055 China Institute of Population Science Peking University Beijing 100187 China

Objective To predict neural tube birth defect （NTD） using support vector machine （SVM）. Method The dataset in the pilot area was divided into non overlaid training set and testing set. SVM was trained using the training set and the trained SVM was then used to predict the classification of NTD. Result NTD rate was predicted at village level in the pilot area. The accuracy of the prediction was 71.50% for the training dataset and 68.57% for the test dataset respectively. Conclusion Results from this study have shown that SVM is applicable to the prediction of NTD.

关键词： NTD Prediction Small sample SVM

Variational quantum attacks threaten advanced encryption standard based symmetric cryptography

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Science China(information Sciences) 2022年第10期65卷 31-42页

作者： Zeguo WANG Shijie WEI Gui-Lu LONG Lajos HANZO State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Beijing Academy of Quantum information Sciences Beijing National Research center for information Science and Technology School of Information Tsinghua University Frontier Science center for Quantum information Department of Electronics and Computer Science (ECS) University of Southampton

We propose a variational quantum attack algorithm(VQAA) for classical advanced encryption standard(AES)-like symmetric cryptography, as exemplified by the simplified-data encryption standard(S-DES). In the VQAA, the known ciphertext is encoded as the ground state of a Hamiltonian that is constructed through a regular graph, and the ground state can be found using a variational approach. We designed the ansatz and cost function for the S-DES’s variational quantum attack. It is surprising that sometimes the VQAA is even faster than Grover’s algorithm as demonstrated by our simulation results. The relationships of the entanglement entropy, concurrence, and the cost function are investigated, which indicate that entanglement plays a crucial role in the speedup.

关键词： S-DES VQA ansatz cost function optimization

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INTERACTIVE KNOWLEDGE LEARNING BY ARTIFICIAL INTELLIGENCE FOR SMALLHOLDERS

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Frontiers of Agricultural Science and Engineering 2023年第4期10卷 648-653页

作者： Weili ZHANG Renlian ZHANG Hongjie JI Anja SEVERIN Zhaojun LI Institute of Agricultural resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China. Electrical Engineering and information Technology Faculty Technical University of MunichMunich 80333Germany

Enhancement of farming management relies heavily on enhancing farmer *** the past,both the direct learning approach and the personnel extension system for improving fertilization practices of smallholders has proven insufficiently ***,this article proposes an interactive knowledge learning approach using artificial intelligence as a promising *** system consists of two *** first is a dialog interface that accepts information from farmers about their current farming *** second part is an intelligent decision system,which categorizes the information provided by farmers in two *** first consists of onfarm constraints,such as fertilizer resources,split application times and *** second comprises knowledge-based practices by farmers,such as nutrient in-and output balance,ratios of different nutrients and the ratios of each split nutrient amount to the total nutrient *** interactive knowledge learning approach aims to identify and rectify incorrect practices in the knowledge-based category while considering the farmer's available finance,labor,and fertilizer *** show that the interactive knowledge learning approach can make a strong contribution to prevention of the overuse of nitrogen and phosphorus fertilizers,and mitigating agricultural non-point sourcepollution.

关键词： finance prevention farming

Numerical Investigation and Optimization of SBS-Based Slow-Light Using Filtered Incoherent Pump

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Chinese Physics Letters 2009年第12期26卷 110-113页

作者：郑狄潘炜闫连山罗斌邹喜华温坤华江宁 center for information Photonics and Communications School of Information Science and Technology Southwest Jiaotong University Chengdu 610031

The performance of stimulated Brillouin scattering （SBS）-based slow light using a novel spectrally-sliced broadband incoherent pump source is numerically studied. The profile of the pump-power spectrum is determined by the transmission spectra of the optical filter followed by the polarized broadband incoherent pump source. We also investigate the performance of Gaussian-type and super-Gaussian-type filtering under different spectrally-slicedbandwidths and pump power levels for 2.5Gbit/s return-to-zero pulse （50% duty-cycle）. The pulse broadening is characterized by the full width of half maximum （FWHM） and the rms pulse width, respectively. However,the results obtained by the two kinds of measurement methods deviate from each other with increasing pump power. Compared with the regular Gaussian-type filtering, the pulse broadening can be significantly reduced using super-Gaussian-type filtering at the cost of a small reduction in delay time. Furthermore, the maximum improvement in pulse broadening of ＆#8710; BFWHM =28.4% and ＆#8710; B RMS =10.4% is achieved by using a five-order super-Gaussian-type filter and a pump power of 500mW.

关键词： Chinese climate network complex systems small world community

The Application Achievements And Perspective Of CBERS Series Satellite Imagery

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Aerospace China 2009年第1期10卷 10-14页

作者： Li Xingchao Qi Xueyong Lu Yilin China center for resources Satellite Data and Application

Since the first China-Brazil Earth resources Satellite(CBERS-1), launched in 1999,the CBERS data has been applied in many fields *** social and economic benefits have been achieved. This article presents the application achievements during the past nine years, and gives a perspective for the *** these applications demonstrate that the CBERS data has been an important data source for resources investigation

关键词：中巴地球资源卫星应用卫星图像卫星系列展望卫星数据 CBERS 经济效益