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41.
Xueyan Hou Cunjin Xue Wanjiao Song Lijuan Qin Xing Fan 《International journal of remote sensing》2014,35(11-12):4138-4155
The northwestern Pacific Ocean is a complex region with significant biological spatial variations on a seasonal timescale. To investigate the joint variation patterns on both seasonal and interannual timescales, a season-reliant empirical orthogonal function (S-EOF) analysis was applied to seasonal mean chlorophyll-a concentration (chl-a) anomalies in the northwestern Pacific Ocean during the period 1998–2010. The first two dominant modes accounted for nearly 31% of the total interannual variance, with the second S-EOF mode (S-EOF2) lagging behind the first S-EOF mode (S-EOF1) by one year. S-EOF1 featured a strong variation pattern to the north of 30° N, with maximum chl-a in winter and minimum chl-a in summer. However, S-EOF2 indicated an opposite seasonally evolving pattern compared with S-EOF1, with chl-a increasing along the Kuroshio and extension current from boreal winter to autumn. Both these modes revealed significant relationships with climate-related indices. The two modes corresponded to the central Pacific (CP) La Niña developing episodes and the turnaround from eastern Pacific (EP) La Niña to CP El Niño, respectively. Both modes were associated with the cold phase of the Pacific Decadal Oscillation, which played an important role in prolonging the impact of the El Niño/Southern Oscillation on chl-a seasonal evolution from 1998 to 2010. In addition, we discuss the possible factors dominating chl-a seasonal variation, in terms of the subregions of the northwestern Pacific Ocean. In the subtropical northwestern Pacific Ocean (15° N – 30° N), the chl-a growth was primarily nutrient-limited, whereas in the mid-latitude northwestern Pacific Ocean (35° N – 50° N), the chl-a growth was mainly light-limited. 相似文献
42.
为了保证广角摄像机在现代机器人视觉定位应用中的准确性,以广角摄像机像素坐标的反畸变过程为研究对象,提出一种在畸变对应表的基础上使用中心迭代法以及区域插值法确定物体实际位置的方法。通过实验证明了该方法能够测量物体的位置,其精度能够满足工业使用要求。 相似文献
43.
44.
利用米曲霉对牛乳进行发酵,通过单因子及正交试验以菌丝体干重为指标对其在牛乳中的生长进行了研究.结果表明:接种量为4%,装液量为30mL,摇床转速为180r/min时菌丝体干重可达到最大.此外测得最大菌丝体干重时的蛋白质分解率可达35.6%. 相似文献
45.
透过节能减排政策和制度看中国节能减排 总被引:2,自引:0,他引:2
随着世界人口的增长、现代工业的高速发展,不可再生资源遭到掠夺式开采、能源消耗几何级增长、环境污染程度大大超出了生态系统的承受能力。如何解决能源短缺与污染严重对经济和社会发展的影响已经成为世界性的难题,我国同样如此。因此,加强对节能减排体系的研究,对我国节能减排工作的开展具有非常重要的意义。对我国节能减排的政策和制度进行剖析,指出了我国节能减排政策、制度以及做法中存在的问题,并提出解决的方法。 相似文献
46.
This paper presents a transient axial dispersion model for an isothermal, catalytic fluidized bed reactor, which is frequently employed in synthetic production processes including coal gasification and liquefaction. A non-linear chemical reaction is considered to occur in the reactor. This model of a fluidized bed reactor takes into account the axial dispersion in the three phases, bubble, cloud-wake and emulsion. The physical properties along the axial coordinate are invariant in the model. Transient characteristics of the gas reactant, and the length of the transient period have been examined based on the model. The model compares favorably with experimental data in the steady state condition. 相似文献
47.
Paul S. K. Choi Liang T. Fan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1973,23(7):531-548
Mathematical models are developed for the transient behaviour of encapsulated enzyme reactor systems such as the continuous stirred tank reactor (CSTR) and the packed bed tubular reactor. The rate processes taking place in the encapsulated enzyme bed are approximated by using a combined rate control model of enzyme reaction and membrane diffusion. The change in transient substrate concentration is obtained by using the developed rate expression in the material balance over the substrate as a function of time for the CSTR and as a function of time and position for the packed bed tubular reactor. The effects of various parameters such as the enzymic reaction rate constant, Michaelis constant, diffusional resistance of membranes, and Peclet number on the substrate concentration distribution, which varies with respect to operating time, are investigated. This study affords insight into the transient operating characteristics of the encapsulated enzyme reactor system. The results should be useful in understanding the start-up performance of the reactor systems and to control such reactor systems at desired operating conditions. 相似文献
48.
Multibody System Dynamics - A recursive rotational-coordinate-based formulation of a planar Euler–Bernoulli beam is developed, where large displacements, deformations, and rotations are... 相似文献
49.
While the significance of oscillator dynamics and coupling structure to synchronization behaviors has been well addressed in the literature, little attention has been paid to the possible influence of coupling functions. In the present paper, adopting the scheme of dual-channel time-delayed couplings, we investigate how the synchronization behaviors of networked chaotic oscillators are influenced by parameters in the coupling functions. It is found that, with the introduction of the second coupling channel, the synchronization region, as calculated according to the method of master stability function (MSF), can be largely modified. In particular, by a slight change of the time delay, it is found that the synchronization region can be significantly adjusted, or even switched from non-existing to existing. We demonstrate this interesting phenomenon for both situations of processing and propagation induced time delays, as well as for different coupling functions. Our studies shed new light on the mechanism of chaos synchronization, and may potentially be used for the control of complex network dynamics. 相似文献
50.
张帆 《吉林化工学院学报》2015,(7):76-79
采用目标追求的入世、出世量表筛选出入世水平高组(70名)和低组(72)大学生,出世水平高组(68名)和低组(71名)大学生,探讨不同入世、出世水平大学生在奖学金申请、选修课和求职应聘三种决策任务领域上的框架效应及其在性别上的特点。结果发现:(1)不同出入世水平大学生在决策任务上的框架效应特点不同,入世水平高分组和低分组、出世水平高分组和低分组在奖学金申请问题上均出现了经典的框架效应;(2)在奖学金申请问题上,男性被试和女性被试的选择出现了明显的经典的框架效应。 相似文献