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101.
Reported here is a rapid, sensitive and relatively inexpensive procedure using gas chromatography with nitrogen-phosphorus detection (GC-NPD) to quantify buspirone levels in brains of rats. The analyte was directly extracted from brain homogenate with toluene after basification and then subjected to GC-NPD analysis using a capillary column. The calibration curves were linear over the range of 10 to 320 ng per 2 ml of brain homogenate, with typical r2 values >0.99. The assay was highly reproducible and gave peaks with excellent chromatographic properties.  相似文献   
102.
中国南海北部二氧化碳气成因   总被引:3,自引:0,他引:3  
中国南海北部海域在油气勘探中发现了CO_2气,对油气有无影响?在借鉴世界、中国东部陆地CO_2气成因研究成果的基础上,从分析研究区CO_2,气的分布入手,采用多种方法,在综合分析基础上,对本区CO_2气藏进行分类.认为研究区CO_2;气藏为无机成因,其特征受各盆地或地区具体地质条件的控制.哈萨克斯坦引起了国际石油界的很大关注,但它并不是前苏联唯一的具吸引力之地.美国地质调查调查所(丹佛)和AAPG今年著名讲演者Gregory F Ulmishek说.前苏联有20多个沉积盆地生产油气或具有尚未开采的发现.Ulmishek 1980年到美国前,获得过莫斯科石油学院地质学硕士学位,作为一个地质学家在前苏联工作过23年.他的1993—1994年题为“前苏联主要油气地质学及勘探潜力”的著名演讲在1993年12月6日至17日和1994年3月28日至4月8日的巡回活动中推出.  相似文献   
103.
Zhan  Choujun  Zheng  Yufan  Lai  Zhikang  Hao  Tianyong  Li  Bing 《Neural computing & applications》2021,33(10):4915-4928
Neural Computing and Applications - At the end of 2019, a new coronavirus (COVID-19) epidemic has triggered global public health concern. Here, a model integrating the daily intercity migration...  相似文献   
104.
This note presents an analysis of the octonionic form of the division algebraic support vector regressor (SVR) first introduced by Shilton A detailed derivation of the dual form is given, and three conditions under which it is analogous to the quaternionic case are exhibited. It is shown that, in the general case of an octonionic-valued feature map, the usual "kernel trick" breaks down. The cause of this (and its interpretation) is discussed in some detail, along with potential ways of extending kernel methods to take advantage of the distinct features present in the general case. Finally, the octonionic SVR is applied to an example gait analysis problem, and its performance is compared to that of the least squares SVR, the Clifford SVR, and the multidimensional SVR.  相似文献   
105.
Cloud computing has become a promising paradigm as next generation computing model, by providing computation, software, data access, and storage services that do not need to know the location of physical resources interconnected across the globe providing such services. In such an environment, important issues as information sharing and resource/service discovery arise. In order to overcome critical limitations in centralized approaches for information sharing and resource/service discovery, this paper proposes a framework of a scalable multi-attribute hybrid overlay featured with decentralized information sharing, flexible resource/service discovery, fault tolerance and load balancing. Additionally, the proposed hybrid overlay integrates a structured P2P system with an unstructured one to support complex queries. Mechanisms such as load balancing and fault tolerance implemented in our proposed system to improve the overall system performance are also discussed. Experimental results show that the performance of the proposed approach is feasible and stable, as the proposed hybrid overlay improves system performance by reducing the number of routing hops and balancing the load by migrating requests.  相似文献   
106.
Fuzzy local maximal marginal embedding for feature extraction   总被引:1,自引:0,他引:1  
In graph-based linear dimensionality reduction algorithms, it is crucial to construct a neighbor graph that can correctly reflect the relationship between samples. This paper presents an improved algorithm called fuzzy local maximal marginal embedding (FLMME) for linear dimensionality reduction. Significantly differing from the existing graph-based algorithms is that two novel fuzzy gradual graphs are constructed in FLMME, which help to pull the near neighbor samples in same class nearer and nearer and repel the far neighbor samples of margin between different classes farther and farther when they are projected to feature subspace. Through the fuzzy gradual graphs, FLMME algorithm has lower sensitivities to the sample variations caused by varying illumination, expression, viewing conditions and shapes. The proposed FLMME algorithm is evaluated through experiments by using the WINE database, the Yale and ORL face image databases and the USPS handwriting digital databases. The results show that the FLMME outperforms PCA, LDA, LPP and local maximal marginal embedding.  相似文献   
107.
The paper presents a novel blind watermarking scheme for image copyright protection, which is developed in the discrete wavelet transform (DWT) and is based on the singular value decomposition (SVD) and the support vector regression (SVR). Its embedding algorithm hides a watermark bit in the low–low (LL) subband of a target non-overlap block of the host image by modifying a coefficient of U component on SVD version of the block. A blind watermark-extraction is designed using a trained SVR to estimate original coefficients. Subsequently, the watermark bit can be computed using the watermarked coefficient and its corresponding estimate coefficient. Additionally, the particle swarm optimization (PSO) is further utilized to optimize the proposed scheme. Experimental results show the proposed scheme possesses significant improvements in both transparency and robustness, and is superior to existing methods under consideration here.  相似文献   
108.
新的现代化技术服务于教育是高职院校现代教育发展的必然趋势,文章系统地叙述了高职院校为进一步推动物联网在教育与教学设备监控的应用,做了不断的探索和实践,以期对高职院校的教育与教学设备监控建设工作提供一些借鉴。  相似文献   
109.
一种高动态范围图像可视化算法*   总被引:4,自引:0,他引:4  
提出的自适应HDR图像可视化算法中,输入图像被分解为基本层和细节层.该算法将整体明暗效果的显示看做整体问题,对表示亮度的基本层采用基于整体统计信息的直方图调整算法处理;可视细节信息的保持作为局部问题,算法采用自适应细节增强算法处理细节层.通过定义映射图对细节增强后的图像进行最终映射,将两方面结合起来得到最终结果.实验结果表明,该算法能对HDR图像进行较高视觉质量的显示.  相似文献   
110.
基于虚拟仪器的水电机组在线状态监测系统的研究*   总被引:3,自引:0,他引:3  
随着水电机组状态检修的不断开展, 需要实现对机组的状态监测, 及时了解机组的运行情况并能及时处理。考虑到水电机组状态监测的多样性和复杂性, 结合实际, 提出水电机组在线状态监测的项目和基于PXI 总线仪器和LabVIEW 的具体实施方案。状态监测系统通过对水电机组状态量的采集、处理和分析, 来实现水电机组运行状态在线实时监测, 极大地提高了机组利用率。该系统在水电机组的状态检修中得到了实际应用。  相似文献   
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