利用无人机遥感技术对农田进行监测并及时发现田间异常对保证农业生产具有重要意义。目前田间异常区域检测需要标注大量的正常与异常样本。然而,异常样本在整个农田区域中占比过小且无法充分收集。特别是农田异常的多样性和不可预知性,...利用无人机遥感技术对农田进行监测并及时发现田间异常对保证农业生产具有重要意义。目前田间异常区域检测需要标注大量的正常与异常样本。然而,异常样本在整个农田区域中占比过小且无法充分收集。特别是农田异常的多样性和不可预知性,对检测方法的适用性提出了更高的要求。针对以上问题,本文提出基于改进PatchSVDD (Patch-level Support Vector Data Description)模型的田间异常区域检测方法,该方法仅使用田间正常区域的标注信息,即可对田间异常区域进行检测和定位。首先,改进方法引入不相邻图像块之间的边界损失函数,从而提升了正常与异常样本边界的判别性,改进了检测的鲁棒性;第二,引入外部记忆组件,通过压缩存储正常样本特征,从而在保证检测精度的基础上有效减少了测试阶段的时间和空间消耗;第三,构建了包含杂草簇、种植缺失、障碍物、双倍种植和积水共5个异常类型的田间异常数据集。本文方法在平均检测AUC(Area Under Curve)值和平均定位AUC值上分别达到了96.9%和94.6%,相比于原算法分别提升1.2%和1.6%,从而验证了方法的有效性。展开更多
A new approach to the research into the distribution of prime pairs is developed, attached with corollaries about the distribution of prime triplets and generally about that of prime h-tuplets. It differs from the usu...A new approach to the research into the distribution of prime pairs is developed, attached with corollaries about the distribution of prime triplets and generally about that of prime h-tuplets. It differs from the usual methods(involving the sieve method) for this kind of research, and bases on Chebyshev inequality and on the computation of average concentration of all the related subsets, and leads to the proofs of following lemma and theorem, attached with four corollaries:[Lemma 1] Among all the prime-pair-subsets there exists at least one such subset (namely one of the sets of generalized prime twins) which is an infinite set.[Theorem 1] All the prime-pair-subsets (namely all sets of generalized prime twins) or infinitely many prime-pair-subsets are infinite sets.[Corollary 1] Among all the prime-triplet-subsets there exists at least one such subset which is an infinite set.[Corollary 2] All the prime-triplet-subsets or infinitely many prime-triplet-subsets are infinite sets.[Corollary 3] Among all the prime-h-tuplet-subsets there exists at least one such subset which is an infinite set, where h is an arbitrary finite integer ≥2.[Corollary 4] All the prime-h-tuplet-subsets or infinitely many prime-h-tuplet-subsets are infinite sets, where h is an arbitrary finite integer ≥2.展开更多
文摘利用无人机遥感技术对农田进行监测并及时发现田间异常对保证农业生产具有重要意义。目前田间异常区域检测需要标注大量的正常与异常样本。然而,异常样本在整个农田区域中占比过小且无法充分收集。特别是农田异常的多样性和不可预知性,对检测方法的适用性提出了更高的要求。针对以上问题,本文提出基于改进PatchSVDD (Patch-level Support Vector Data Description)模型的田间异常区域检测方法,该方法仅使用田间正常区域的标注信息,即可对田间异常区域进行检测和定位。首先,改进方法引入不相邻图像块之间的边界损失函数,从而提升了正常与异常样本边界的判别性,改进了检测的鲁棒性;第二,引入外部记忆组件,通过压缩存储正常样本特征,从而在保证检测精度的基础上有效减少了测试阶段的时间和空间消耗;第三,构建了包含杂草簇、种植缺失、障碍物、双倍种植和积水共5个异常类型的田间异常数据集。本文方法在平均检测AUC(Area Under Curve)值和平均定位AUC值上分别达到了96.9%和94.6%,相比于原算法分别提升1.2%和1.6%,从而验证了方法的有效性。
文摘A new approach to the research into the distribution of prime pairs is developed, attached with corollaries about the distribution of prime triplets and generally about that of prime h-tuplets. It differs from the usual methods(involving the sieve method) for this kind of research, and bases on Chebyshev inequality and on the computation of average concentration of all the related subsets, and leads to the proofs of following lemma and theorem, attached with four corollaries:[Lemma 1] Among all the prime-pair-subsets there exists at least one such subset (namely one of the sets of generalized prime twins) which is an infinite set.[Theorem 1] All the prime-pair-subsets (namely all sets of generalized prime twins) or infinitely many prime-pair-subsets are infinite sets.[Corollary 1] Among all the prime-triplet-subsets there exists at least one such subset which is an infinite set.[Corollary 2] All the prime-triplet-subsets or infinitely many prime-triplet-subsets are infinite sets.[Corollary 3] Among all the prime-h-tuplet-subsets there exists at least one such subset which is an infinite set, where h is an arbitrary finite integer ≥2.[Corollary 4] All the prime-h-tuplet-subsets or infinitely many prime-h-tuplet-subsets are infinite sets, where h is an arbitrary finite integer ≥2.
