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1.
As a decisive attribute, flavour could be influenced by HP treatments through multiple physical and chemical pathways within the high pressure (HP)-assisted meat curing process. This investigation aimed to identify the major pathway influencing volatile flavour patterns of two representative vinasse-cured duck (VCD) products with HP treatments (150–300 MPa/15 min), including wet and dry types, by employing headspace fingerprinting as an untargeted approach. Results suggested that HP treatments greatly lowered moisture contents and increased Warner-Bratzler shear force and thiobarbituric acid reactive substances of the cured samples. According to multivariate models, the volatile flavour patterns of the HP-processed VCD could be clearly separated from the unprocessed samples, but the VCD pressurised at different intensities represented similar volatile fingerprinting, which was validated by e-nose analysis. The discriminant analysis (OPLS-DA) model outlined vinasse-derived ethanol, acetic acid, 3-methyl-1-butanol, 2-methyl-1-butanol, phenethyl alcohol and 2-methyl-3-octanone as the major discriminant aromas across the unpressurised and pressurised samples.  相似文献   
2.
针对肺癌呼出挥发性有机气体(VOCs)中的特定标志物,提出了一种新型的基于荧光卟啉传感器阵列检测系统,并对4种肺癌呼出标志物进行检测研究。通过小波分析等数学工具对测得的荧光光谱数据进行特征提取,然后采用层次聚类、主成分分析等统计学方法对特征向量进行分析。不同体积分数的各类标志物在聚类分析中能够完全正确的聚到一起。通过主成分分析得到的前3个主成分包含了标志物的88%的信息,便能对不同类别的标志物进行识别。研究表明:该荧光卟啉传感器阵列系统能够快速有效地对不同肺癌标志物进行识别,有望在临床中得到应用。  相似文献   
3.
InfiniBand:一种新型的高速互连网络   总被引:4,自引:0,他引:4  
随着计算能力向数据中心的集中,消除性能瓶颈和改进系统管理变得比以往更加重要。I/O子系统是造成这类问题的关键。InfiniBand被认为是可以消除当前I/O架构性能瓶颈的一种新的I/O技术。该文首先分析当前I/O系统的瓶颈问题,然后从IBA整体架构、层次结构、通信机制与VI架构、链路特性与服务质量等方面介绍了InfiniBand的具体情况,最后将Infiniband与其它一些高性能互连网络和标准进行了比较。  相似文献   
4.
In this paper, a two-step phase partitioning strategy is proposed. Firstly, the number of phases is automatically determined according to the intra-class and inter-class similarity of feature space data, thus avoiding excessive manual intervention. Secondly, the phases are partitioned by step-wise adding the kernel entropy extended load matrix (KEELM), avoiding the wrong division of phases caused by unstable state of working condition conversion. A process monitoring model based on multiway kernel entropy independent component analysis (MKEICA) is constructed in each sub-phase to deal with complex batch processes with nonlinear and non-Gaussian properties. A new statistics index based on the idea of high order cumulant analysis (HCA) is constructed in each sub-phase for process monitoring. Compared with the traditional second-order statistics, it can obtain high-order statistical information. Finally, the proposed method is applied to the penicillin simulation platform process and compared with the traditional multiway kernel independent components analysis (MKICA) and HCA methods to verify the effectiveness of the method that is mentioned above.  相似文献   
5.
制备了陈皮挥发油提取物并建立其气相色谱-质谱(GC-MS)指纹图谱,对不同批次的陈皮指纹图谱进行相似度评价;对其共有成分峰面积数据进行主成分分析(PCA)和层次聚类分析(HCA)。建立了具有16个共有峰的新会陈皮挥发油指纹图谱,通过化学计量学分析方法能将新会陈皮和其他陈皮样品准确区分开来;不同采摘期及贮存时间陈皮的成分呈现规律性特征。方法可用于不同产地、采摘期及贮存时间陈皮的鉴别,并为陈皮的质量控制提供依据。  相似文献   
6.
Temperature and selenium are two environmental parameters that potentially affect reproduction and stock recruitment of sturgeon in the San Francisco Bay/Delta Estuary. To identify proteins whose expression is modified by these environmental stressors, we performed a proteomic analysis on larval green and white sturgeons exposed to 18 or 26 °C and micro-injected with Seleno-L-Methionine to reach 8 µg g1 selenium body burden, with L-Methionine as a control. Selenium and high temperature induced mortalities and abnormal morphologies in both species, with a higher mortality in green sturgeon. Larval proteins were separated by two-dimensional gel electrophoresis and differential abundances were detected following spot quantitation and hierarchical cluster analysis. In green sturgeon, 34 of 551 protein spots detected on gels showed a variation in abundance whereas in white sturgeon only 9 of 580 protein spots were differentially expressed (P < 0.01). Gel replicates were first grouped according to heat treatment. Fifteen of these spots were identified using MALDI TOF/TOF mass spectrometry. Proteins involved in protein folding, protein synthesis, protein degradation, ATP supply and structural proteins changed in abundance in response to heat and/or selenium. 40S ribosomal protein SA, FK506-binding protein 10, 65 kDa regulatory subunit A of protein phosphatase 2, protein disulfide isomerase, stress-induced-phosphoprotein 1, suppression of tumorigenicity 13 and collagen type II alpha 1, were differentially expressed in high temperature treatment only. Serine/arginine repetitive matrix protein 1, creatine kinase, serine peptidase inhibitor Kazal type 5 and HSP90 were sensitive to combined temperature and selenium exposure. Valosin-containing protein, a protein involved in aggresome formation and in protein quality control decreased more than 50% in response to selenium treatment. Potential use of such proteins as biomarkers of environmental stressors in larval sturgeons could indicate early warning signals preceding population decline.  相似文献   
7.
Efficient resource management is mandatory to achieve maximum system capacity for next generation communications systems. Resource management deals with the available spectral band, time, power, and space for a transmission signal. It includes (i) the frequency planning, (ii) the selection of transmit power, and (iii) the assignment of the channels and access nodes to the users. The paper presents a generalized notation as well as graph algorithms for resource management problems. Impairment graphs can be used for frequency planning, whereas flow graphs are suitable for channel access problems. To evaluate the performance of the resource management, service criteria (such as blocking or the carrier to interference ratio C/I) or efficiency criteria (bandwidth requirements) can be derived from the graphs. The resource management techniques are applied to satellite networks with non‐geostationary orbits yielding time‐variant network topologies. As a simple example, the channel assignment and capacity optimization of the EuroSky Way system are shown. Furthermore, a comparison of fixed, dynamic and hybrid channel allocation schemes (FCA, DCA, HCA) for a typical MEO satellite scenario is given. Satellite diversity and its impact on bandwidth requirement and transmission quality is also examined. Finally, it is shown how spread spectrum systems can be investigated with the presented tools. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
8.
细胞自动机的理论研究主要包括细胞自动机的分析和综合两个方面,而细胞自动机的可逆性分析则是细胞自动机分析中的核心问题。60/102/204混合细胞自动机作为一类重要的细胞自动机,利用矩阵分析方法将其状态转移表示为矩阵方程,从而分析其可逆性、可逆细胞自动机的数目和可逆细胞自动机的构造。60/102/204混合细胞自动机可逆性分析对于其在密码学、通信和测试等领域的应用具有重要意义。  相似文献   
9.
A model for the behavior of horizontally high‐cycle loaded piles For the prediction of the deformation for long or intermediate long piles under lateral high cycle load, embedded in non‐cohesive soil, a simplified engineering model for drained conditions is developed based on the high cycle accumulation (HCA) model of Niemunis , Wichtmann and Triantafyllidis [1]. The monotonic soil deformation under static load is approximated by elastic springs, placed around the pile, whereas the accumulation of soil deformations under cyclic loading is modelled by viscous dashpots (cyclic creep) according to the HCA model. In most instances this contemplation is physically validated by element tests. In conjunction with the pile the spring‐dashpot elements represent an elastically embedded beam system. Two versions of the model with a two‐sided arrangement of springs and dashpots on the Lee‐ and Luv‐side and a one‐sided arrangement only on the Lee‐side will be presented. The pile displacement prediction of the model is compared with the results obtained by existing engineering models already known in the literature and the solution of a 3‐D‐finite element simulation with the HCA model.  相似文献   
10.
为探究我国东北地区4种代表性粳米(香米五优稻4号、绥粳18和非香米龙粳31、盐丰47)香气组分差异,通过顶空-固相微萃取-气相色谱-质谱联用(Headspace-solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)和快速气相电子鼻(Flash gas chromatography electronic nose,Flash GC e-nose)技术对粳米香气组分进行鉴定。本研究采用正交偏最小二乘法-判别分析(Orthogonal partial least squares-discriminant analysis,OPLS-DA)和层次聚类分析(Hierarchical clustering analysis,HCA)等方法对4种粳米香气组分进行分析,结果表明,4种粳米的主要香气组分构成类似,以己醛、壬醛等醛类为主;五优稻4号主要香气成分含量显著(p≤0.05)高于其它3个品种粳米,使得其香气更加浓郁;关于粳米香气组分鉴定技术,GC-MS技术的准确度和检测范围优于电子鼻技术,而检测效率低于电子鼻技术。  相似文献   
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