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971.
现有流形学习算法在学习人脸数据时,假设所有数据点位于单一低维嵌入流形之上,当数据点实际分布在不同的流形上时,单流形假设就会影响数据真实空间结构。为此提出一种基于多邻域保持嵌入(multiple neighborhood preserving embedding, M-NPE)的学习算法来发现不同类别数据在不同维度的低维嵌入空间中分布的多流形结构。首先,单独学习不同类别数据的流形,得到反映其本质特征的流形;再通过遗传算法搜索每个流形的最优维数;最后依据最小重构误差分类器对样本分类。在Extended Yale B和CMU PIE这2个大型人脸库上实验结果验证了该算法的有效性。 相似文献
972.
973.
通过杂交油菜不同栽培方式对经济效益比较试验研究.结果表明:翻梨移栽产值最高943.8元/667m2,其次是谷林套播产值870元/667m2,不同期直播产值最低593.3元/667m2;投入翻犁移栽最高620元/667m2,其次是谷林套播510元/667m2,不同期直播最低480元/667m2;净产值谷林套播最高360元/667m2,其次是同期直播334.2元/667m2,不同期直播最低113.3/667m2;投产比谷林套播最高1∶1.71,其次是同期直播1∶1.67,不同期直播最低1∶ 1.24. 相似文献
974.
利用染色体片段代换系定位陆地棉株高QTL 总被引:4,自引:0,他引:4
以陆地棉中棉所36为轮回亲本和海岛棉海1为供体亲本, 构建染色体片段代换系。为了能检测到稳定的株高QTL,将三个代换系群体(BC5F3, BC5F3:4和BC5F3:5)在5个环境中种植,2009年和2010年分别在河南安阳种植BC5F3单株、BC5F3:4株行, 2011年分别在河南安阳、辽宁辽阳和新疆石河子种植BC5F3:4株系。结果表明,在不同群体环境中株高的超亲比例为53.43%~88.97%。从早期构建的总图距为5088.28 cM, 含有2280个SSR标记位点,覆盖26条染色体的遗传连锁图谱中筛选标记,对408个单株进行的SSR鉴定,结果检测到16个株高QTL,分布在10条染色体上。单个QTL解释的表型变异为7.35%~13.17%。有7个QTL在2个以上环境被检测到。与标记MUSS563紧密连锁的qPH-15-19在一个环境中被检测到,在前人的研究中也有报道。这些结果为进一步精细定位QTL、基因克隆、分子辅助选择等研究奠定基础。 相似文献
975.
GenBank数据库中黄麻EST-SSR标记的开发及其通用性评价 总被引:1,自引:0,他引:1
本研究从GenBank公共数据库中下载黄麻表达序列标签838条,利用SSRPrimer软件对其进行SSR位点查找,利用Primer 3.0软件设计66对SSR引物,通过琼脂糖凝胶研究这些SSR引物的PCR扩增特点,以检测其多态性。结果表明,66对SSR引物在黄麻属6个不同类型材料的扩增中,42 (63.6%)对引物至少在2个材料之间存在多态性。(AT)n重复基元和(GC-)n丰富的三核苷酸重复基元多态性较高,可作为黄麻SSR标记引物设计的首选。黄麻EST-SSR标记开发效率较高,不仅可以丰富黄麻分子标记的数量,而且为剖析黄麻重要性状的遗传机制奠定基础,这对于黄麻的遗传基础研究具有重要应用价值。 相似文献
976.
The Kalman filter algorithm can be used to estimate the state of charge (SOC) of power batteries, however, it easily causes divergence due to uncertain of system noise and its estimation performance is affected by model. An adaptive Kalman filter algorithm is adopted to dynamically estimate SOC of lithium iron phosphate batteries for application in electric vehicles. At first, an equivalent circuit model, appropriate for SOC estimation is built after studying battery models. Then some charging and discharging experiments are carried out for parameter identification and the results are verified. At last, the adaptive Kalman filter algorithm is used on this model for on-line SOC estimation under unknown interfering noise. Simulation results show that adaptive Kalman filter method can correct SOC estimation error caused by tiny model error online, and the estimate accuracy is higher than Kalman filter method. Adaptive Kalman filter algorithm can also correct the initial error. Full-cycle test in electric vehicles proves that the algorithm is appropriate for SOC estimation of lithium iron phosphate battery. 相似文献
977.
In order to implement the security management of management information system (MIS), a target-based security management architecture is proposed. For MIS users, the user interface (UI) is the only way to interact with the MIS system, so all the objects (targets) which need to be managed on UI is registered first, thus for every target the state such as enabled, not enabled, visible, not visible, readonly etc., is assigned. For some users, a set of targets with some state is assigned so that the management granularity in MIS can reach any degree. This approach provides a very flexible way to the security management in MIS. 相似文献
978.
979.
As the BEM was used in the knaggy domain,its approach error was big.Domain Decomposition Method change the problem in the knaggy domain to the problem in several convex domains which do not wrap.The whole solution is gained by alternating boundary conditions between Dirichlet condition and Neumann condition on the common boundary.Domain Decomposition Method for Stokes equations in the anomalistic knaggy domain is presented,the example of Domain Decomposition Method in the flow of the lake in GuiYang City is given. 相似文献
980.
Intake camshaft equipped with continuously adjustable cam phasing units is applied to a 486Q gasoline engine. Phasing strategies are researched through engine cycle simulation to achieve superior engine performance. The simulation results show that at high load and low and moderate speed of the engine,phasing adjustment can lead to 6% to 8% increase in power performance because phasing advance contributes to suppressing intake backflow at IVC(intake valve closed). Cam phases obtained from numerical optimization have good agreement with engine test. At moderate load,cycle simulations show that phasing advance can increase residual gas coefficient from 9% to 20%,and reduce NO emission by 80%,BSFC(brake specific fuel consumption) by 2% at a demonstration operation. With regard to fuel economy and emissions,adjustment and optimization of intake phasing at moderate load are further verified by engine test. At low load,technical approaches to enhance combustion stability,reduce HC emission and improve cold start are investigated. The effectiveness of suppressing exhaust backflow into intake duct by phasing retard is testified by simulation. Phasing changes at the operating condition are optimally obtained by engine test for improvement of combustion stability. 相似文献