期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
基于PSPNet的遥感影像城市建成区提取及其优化方法 被引量:16
1
作者 刘钊 廖斐凡 赵桐 《国土资源遥感》 CSCD 北大核心 2020年第4期84-89,共6页
利用高分辨率卫星遥感影像提取建成区边界对于城市扩张监测和城市发展规划具有重要意义。为获取高精度高空间分辨率的建成区数据,本研究通过归一化建筑指数(normalized difference built-up index,NDBI)加人工目视解译方法构建城市建成... 利用高分辨率卫星遥感影像提取建成区边界对于城市扩张监测和城市发展规划具有重要意义。为获取高精度高空间分辨率的建成区数据,本研究通过归一化建筑指数(normalized difference built-up index,NDBI)加人工目视解译方法构建城市建成区遥感影像数据集,分别采用传统机器学习方法和包括PSPNet在内的4种深度学习语义分割网络对Sentinel-2影像进行建成区提取,训练结果表明PSPNet网络对于建成区的提取具有最高的精度(训练集交并集比(intersection over umion,IOU)为79.5%)。提出Overlapsize方法对PSPNet的提取结果进行优化,进一步提高了建成区提取准确率,该方法在训练集上的IOU达到80.5%,在测试集上的IOU达到了83.1%,利用PSPNet+Overlapsize提取建成区的方法相较于传统机器学习方法具有实际应用意义。 展开更多
关键词 建成区提取 深度学习 卷积神经网络 语义分割 PSPNet overlapsize
在线阅读 下载PDF
Computer-Assisted DEM-Based Aero Photography Design 被引量:2
2
作者 FAN Yewen GONG Jianya +1 位作者 TAN Chengguo WANG Ruiyao 《Geo-Spatial Information Science》 2008年第1期26-30,共5页
In aerial photography, the primary factor is terrain undulation. However, most of the external aerial photography software used for aerial photography design do not take terrain undulation influence into consideration... In aerial photography, the primary factor is terrain undulation. However, most of the external aerial photography software used for aerial photography design do not take terrain undulation influence into consideration. Therefore, the design result has comparative randomicity and "gaps" are expected. An aerial photography design system is developed by analyzing the terrain undulation influence to the design result with DEM data so that the forward overlap and side overlap can be justified according to the block terrain undulation to meet specifications or standards. The data designed by this system is compared with the real flying data. The results show that making use of DEM to assist in aerial photography design can ensure that the designed result fits the real terrain better. 展开更多
关键词 aerial photography design digital elevation model side overlaps forward overlaps
在线阅读 下载PDF
International Standardization of Blockchain and Distributed Ledger Technology:Overlaps,Gaps and Challenges 被引量:1
3
作者 Xiangjuan Jia Jing Xu +3 位作者 Mengwei Han Qing Zhang Lu Zhang Xiaofeng Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期1491-1523,共33页
As one of the most concerned digital technologies in recent years,blockchain and distributed ledger technology are an important driving force for a new round of technological development.It is currently in the process... As one of the most concerned digital technologies in recent years,blockchain and distributed ledger technology are an important driving force for a new round of technological development.It is currently in the process of accelerating its evolution and maturity,and has gradually integrated with other digital technologies.It has been applied in many industries,providing decentralized solutions for various industries,realizing innovative storage models,and building a new trust system.As blockchain technology is officially incorporated into China’s new information infrastructure category,the application fields of blockchain have expanded rapidly,gradually extending from the financial field and government affairs to other fields in the real economy.At the same time,with the continuous development of the globalized economy,blockchain technology will also have a profound impact on international technological and economic development.Therefore,for the healthy and orderly development and real implementation of the blockchain industry,standardize the application of blockchain,effectively break through the cognitive and technical barriers between different countries,industries and systems on a global scale,prevent application risks,the development of the global blockchain industry needs standardization basis,which is particularly important and urgent.A sound standard system is an important key to the successful development of technology,and formulating the right standard at the right time for technology development helps ensure the ease of use and interoperability of the technology.From the perspective of international standardization,this article first introduces the general situation of ISO,ITU-T,IEEE,W3C and other international standardization organizations,and sorts out the status quo of the blockchain standardization working groups of mainstream international standardization organizations.All blockchain-related standards under development have been analyzed for the characteristics of international blockchain technology standards and industry application standards.Through data analysis,the overlaps,differences and conflicts in the field of international blockchain standard formulation are sorted out,and suggestions for blockchain standardization work in the application and development of blockchain technology standardization by international organizations and industries are put forward.The plans and layouts of future international standards are summarized to help the development of the international standardization of blockchain. 展开更多
关键词 ISO ITU-T IEEE blockchain distributed ledger technology international standard standardization status OVERLAPS GAPS CHALLENGES
在线阅读 下载PDF
Landau damping of electrons with bouncing motion in a radio-frequency plasma
4
作者 Jun Tao Nong Xiang +1 位作者 Yemin Hu Yueheng Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期484-494,共11页
One-dimensional particle simulations have been conducted to study the interaction between a radio-frequency electrostatic wave and electrons with bouncing motion.It is shown that bounce resonance heating can occur at ... One-dimensional particle simulations have been conducted to study the interaction between a radio-frequency electrostatic wave and electrons with bouncing motion.It is shown that bounce resonance heating can occur at the first few harmonics of the bounce frequency(nω_(b),n=1,2,3,...).In the parameter regimes in which bounce resonance overlaps with Landau resonance,the higher harmonic bounce resonance may accelerate electrons at the velocity much lower than the wave phase velocity to Landau resonance region,enhancing Landau damping of the wave.Meanwhile,Landau resonance can increase the number of electrons in the lower harmonic bounce resonance region.Thus electrons can be efficiently heated.The result might be applicable for collisionless electron heating in low-temperature plasma discharges. 展开更多
关键词 first few harmonics bounce resonance Landau resonance resonance overlaps
原文传递
The Study of the Secrets of the Genetic Code
5
作者 N. N Kozlov 《Journal of Computer and Communications》 2018年第7期64-83,共20页
The disclosure of many secrets of the genetic code was facilitated by the fact that it was carried out on the basis of mathematical analysis of experimental data: the diversity of genes, their structures and genetic c... The disclosure of many secrets of the genetic code was facilitated by the fact that it was carried out on the basis of mathematical analysis of experimental data: the diversity of genes, their structures and genetic codes. New properties of the genetic code are presented and its most important integral characteristics are established. Two groups of such characteristics were distinguished. The first group refers to the integral characteristics for the areas of DNA, where genes are broken down in pairs and all 5 cases of overlap, allowed by the structure of DNA, were investigated. The second group of characteristics refers to the most extended areas of DNA in which there is no genetic overlap. The interrelation of the established integral characteristics in these groups is shown. As a result, a number of previously unknown effects were discovered. It was possible to establish two functions in which all the over-understood codons in mitochondrial genetic codes (human and other organizations) participate, as well as a significant difference in the integral characteristics of such codes compared to the standard code. Other properties of the structure of the genetic code following from the obtained results are also established. The obtained results allowed us to set and solve one of the new breakthrough problems—the calculation of the genetic code. The full version of the solution to this problem was published in this journal in August 2017. 展开更多
关键词 Genetic CODE OVERLAPPING Genes DEGENERACY CODE CODE IRREGULARITIES Potential CODE for OVERLAPS Common Property Codes Integral Characteristics CODE Deviation CODE Elementary OVERLAPS Role-Reinterpreted CODONS CODE Is Not Arbitrary
暂未订购
Feeding ecology of the mangrove oyster, <i>Crassostrea gasar</i>(Dautzenberg, 1891) in traditional farming at the coastal zone of Benin, West Africa
6
作者 Alphonse Adite Stanislas P. Sonon Ghelus L. Gbedjissi 《Natural Science》 2013年第12期1238-1248,共11页
Wild collection management and farming of the mangrove oyster (Crassostrea gasar) occurring widely at the Benin (West Africa) coastal zone require knowledge on the feeding ecology to explore energy sources and nutriti... Wild collection management and farming of the mangrove oyster (Crassostrea gasar) occurring widely at the Benin (West Africa) coastal zone require knowledge on the feeding ecology to explore energy sources and nutritional needs. Six hundred thirty (630) individuals of C. gasar have been sampled in the rearing site at the Benin coastal lagoon to investigate on the trophic ecology of this cultivated bivalve. The diet analysis revealed that C. gasar is a filter-feeder foraging mainly on phytoplankton (72.70%) and substrate particles (22.95%). This trophic specialization results from anatomical structure, mainly the presence of gills which facilitate the filtering of number of plankton taxa. Dominant phytoplanktons ingested comprised of Diatomophycea (33.52%), Chlorophycae (17.19%), Scenedesmacae (13.80%), Dictyosphaeriacae (3.79%), and Pleurococcacae (2.75%). Eight genuses of phytoplankton, Polycystis, Coelosphaerium, Protococcus, Botryoccocus, Crucigenia, Melosira, Cyclotella, and Gyrosigma dominated the diet of C. gasar with aggreated volumetric proportions reaching 69.06% of the diet. Higher occurrences were recorded mainly for Melosira occurring in 263 (41.75%) stomachs, substrate particles in 211 (33.49%), and Polycystis in 151 (23.97%). C. gasar exhibited a high niche breadths varying from 4.54 to 5.78, suggesting that this bivalve consumed a high variety of food items, thus exhibiting a degree of trophic plasticity. Diet overlaps (?jk) among different size classes were high and varied from 0.71 to 0.98, indicating an ontogenetic diet shift pattern in C. gasar. Probably, to adapt to the benthic-muddy environment and to increase survival, C. gasar has evolved a specialized feeding mechanism and strategy to retrieve only needed nutrients for growth and to reject awful and nondigestible foods. Also, at the oyster rearing grounds, there is an evidence of shift in the food web structure leading to an increase of the biological productivity at the coastal zone. The output from this study is a valuable documentation for the sustainable development of oyster aquaculture, wild stock management and conservation. However, further scientific knowledge on nutritional needs, phytoplankton toxicity and habitat degradation, and improvement of farming techniques are required for an integrated oyster management. 展开更多
关键词 Conservation CRASSOSTREA Diet OVERLAPS Farming Filter-Feeder Food Web Foraging Strategy Phytoplankton
暂未订购
Early Childhood Education for Sustainability Through Contradicting and Overlapping Dimensions 被引量:1
7
作者 Liv Torunn Grindheim Yvonne Bakken +1 位作者 Kjellrun Hiis Hauge Marianne Presthus Heggen 《ECNU Review of Education》 2019年第4期374-395,共22页
Purpose:The article investigates how to make a broader understanding of sustainability relevant for early childhood education(ECE)guided by the four dimensions suggested by United Nations Educational,Scientific and Cu... Purpose:The article investigates how to make a broader understanding of sustainability relevant for early childhood education(ECE)guided by the four dimensions suggested by United Nations Educational,Scientific and Cultural Organization:ecological,economic and social/cultural sustainability,and good governance.Design/Approach/Methods:Previous research on ECE on sustainability is discussed in relation to the four dimensions and to Biesta’s concepts of socialization,qualification,and subjectification.Findings:The investigation finds that all four dimensions are necessary in ECE for sustainability,and it suggests how the dimensions can be understood,how they may overlap,and how they can be contradictive.Originality/Value:The article depicts how children’s opportunities to engage and to disturb established ways of thinking can be facilitated through all dimensions. 展开更多
关键词 Conflicts dimensions of sustainability early childhood education OVERLAPS
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部