Results 11 to 20 of about 9,645 (120)
Method of computing e-derivative based on minterm table(基于最小项表计算e导数的方法)
Zhejiang Daxue xuebao. Lixue ban, 2013 给出了布尔函数的e导数、高阶e导数以及e偏导数的定义，在此基础上提出了基于布尔函数1值最小项表计算布尔函数的e导数、高阶e导数以及e偏导数的表格方法.该方法具有简单、不受变量数限制以及易于计算机编程操作等优点.
MARu-xing(马汝星) +1 more
doaj +2 more sources
日本东北MW9.0地震的PI模型参数设置与预测效能回溯性检验
Dizhen xuebao, 2018 以日本局部地区（32.0°N—46.0°N，136.0°E—148.0°E）为研究区域，应用图像信息（PI）方法，获得了不同计算参数模型下包含2011年3月11日日本东北MW9.0地震的多组预测窗热点图像。以0.5°×0.5°和1.0°×1.0°的网格尺度和5—10年预测窗长为主要参数变量，并以R值和受试者工作特征（ROC）方法检验不同参数模型下PI方法的预测效能。结果表明，多组参数模型下MW9.0地震所在预测窗内，其震中所在网格及其摩尔邻近网格均曾出现热点图像，表明PI方法可对日本东北MW9 ...
Cheng Song +5 more
doaj +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2018 地表覆盖是地理国情监测的重要对象，为地理国情分析评价模型提供了可靠的数据源.高效的地表覆盖数据检索方法是挖掘地表覆盖数据潜在价值的前提.由于地表覆盖数据体量庞大、更新频繁，要素分布密集且不均匀，传统的空间检索方法出现了扩展困难、检索能力不足等问题.提出了一种基于HBase与静态多级格网索引的地表覆盖数据空间检索方法，针对地表覆盖数据特征设计了基于HBase的静态多级格网索引，利用MapReduce实现索引并行构建，通过多级过滤的方式，提高了地表覆盖空间范围的查询效率.实验表明，该方法能快速完成大规模 ...
ZHULinying(祝琳莹) +4 more
doaj +1 more source
, 2019 旋转对称逻辑函数在密码学函数构造领域有广泛应用。针对含无关项旋转对称逻辑函数检测中存在的不足，从含无关项逻辑函数的定义和旋转对称函数的性质出发，提出了检测含无关项旋转对称逻辑函数的快速算法。该算法通过判断逻辑函数1 值最小项二进制编码周期旋转后产生的新编码同1 值最小项及无关项二进制编码的重复性实现快速检测。结果表明，快速算法在适用的逻辑函数变量数 ...
LIXiaohua(厉晓华), XUFeng(徐锋)
core +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2014 在分析GPU并行架构和CUDA灵活可编程性基础上，提出了一种基于区间块搜索的等值线并行提取方法，可应用于全球海洋表面温度格网数据的分析.算法有效减少了等值线追踪过程中重复性的格网遍历及不必要的格网搜索.最后，实验采用了不同规模的海表温度场格网数据进行等值线的提取并比较串并行耗时，结果表明：(1)算法能实现全球海洋表面温度等值线的有效提取并提高其效率，尤其对于大规模格网数据；(2)基于所有实验数据，格网规模大于720×1 440时，相较于串行过程GPU执行体现了其效率上的优势 ...
QIANChen(钱宸) +4 more
doaj +1 more source
Conservation Biology, EarlyView.Abstract Measuring area‐based conservation outcomes in tropical forests is challenging due to cryptic human disturbances (e.g., hunting). As a result, comparative studies of management strategies providing quantitative outcomes remain scarce, especially in the Neotropics.
Lucy Perera‐Romero +5 more
wiley +1 more source
PINN-type algorithm for shock capturing of hyperbolic equations(双曲型方程激波捕捉的物理信息神经网络（PINN）算法)
Zhejiang Daxue xuebao. Lixue ban, 2023 双曲型方程的数值求解算法研究一直是偏微分方程研究的热点，其中，双曲型方程的间断捕捉是难点。受物理信息神经网络（physics-informed neural networks，PINN）启发，构造了改进的PINN算法，近似求解双曲型方程的间断问题。将坐标构造的数据集作为神经网络的输入，将PINN算法中的损失函数作为训练输出值与参考解（基于细网格的熵相容格式数据）或准确解的误差值，通过网络优化，最小化损失函数，得到最优网络参数。最后用数值算例验证了算法的可行性，数值结果表明，本文算法能捕捉激波，分辨率高 ...
郑素佩(ZHENG Supei) +3 more
doaj +1 more source
Hobbyist preferences for pet freshwater turtles
Conservation Biology, EarlyView.Abstract The burgeoning pet trade is a primary threat to wild freshwater turtles worldwide. Although the risks from commercial exploitation of turtles have been discussed widely, there is little empirical research on preferences for pet turtles from a hobbyists’ perspective.
Jingjing Zhao +7 more
wiley +1 more source
Comprehensive framework for assessing and optimizing existing research networks
Conservation Biology, EarlyView.Abstract Conservation, monitoring, and research networks, or collections of ecological research sites unified under a common mission of data collection or a research mission, are essential infrastructure for understanding large landscapes. However, most networks developed opportunistically over decades rather than through systematic design, creating ...
Alyson East +2 more
wiley +1 more source
Representation of obligate groundwater‐dwelling copepod diversity in European protected areas
Conservation Biology, EarlyView.Abstract Groundwaters sustain diverse surface ecosystems and are populated by metazoan species, mostly invertebrates, that provide fundamental ecological functions and are often of prominent conservation value due to narrow endemism and high phylogenetic rarity.
Francesco Cerasoli +7 more
wiley +1 more source