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91.
路桂珍 《安徽科技学院学报》1991,(2)
简述陆地卫星多光谱扫描(MSS)影象的特点,着重介绍陆地卫星多光谱扫描影象适用于中、小比例尺的土地资源凋查 相似文献
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Linnea Bodén 《Learning, Media and Technology》2017,42(4):406-419
Focusing on digital text messages containing information about students’ absences and sent to parents by schools, the paper investigates the way school absenteeism is produced within affective assemblages. The paper unfolds a theoretical and methodological approach of ‘going with’ the text messages, in entanglements of affective flows. The empirical engagements, produced together with multiple agents in two Swedish schools, show that within the assemblages of human and nonhuman bodies, the text messages can become ‘stirrers’ that evoke nervousness and anxiety, but also excitement and feelings of control that affect the production and conception of absenteeism. The affective flows of text messages thus travel in all directions, with and against notions of linearity. The conclusion emphasizes how the text messages, as affective materialities, are an inextricable part of the production of school absenteeism in multiple and sometimes unexpected ways. 相似文献
95.
国际互联网的迅速发展,使应用软件的销售模式发生了翻天覆地的变化。企业可以不必购买先进昂贵的应用软件,只需通过ASP就可以在网上及时获得所需的应用软件以及相关的服务。因此,对ASP的定义、分类、市场培育以及前景作了详细分析,并对中国ASP市场的发展做出展望。 相似文献
96.
分子伴侣与蛋白质折叠 总被引:2,自引:0,他引:2
新合成的多肽链必须先经折叠和装配后形成特定的三维结构才具有活性.在多肽链折叠过程中,往往会产生折叠异常蛋白,形成集聚体.分子伴侣可有效地调控多肽链的正确折叠,从而避免集聚体的形成.文章主要对分子伴侣的定义、作用、种类、特性等做一介绍。 相似文献
97.
Ayd?n K?z?lkaya 《Journal of The Franklin Institute》2005,342(1):39-67
In this paper, the problem of estimating the parameters of a two-dimensional autoregressive moving-average (2-D ARMA) model driven by an unobservable input noise is addressed. In order to solve this problem, the relation between the parameters of a 2-D ARMA model and their 2-D equivalent autoregressive (EAR) model parameters is investigated. Based on this relation, a new algorithm is proposed for determining the 2-D ARMA model parameters from the coefficients of the 2-D EAR model. This algorithm is a three-step approach. In the first step, the parameters of the 2-D EAR model that is approximately equivalent to the 2-D ARMA model are estimated by applying 2-D modified Yule-Walker (MYW) equation to the process under consideration. Then, the moving-average parameters of the 2-D ARMA model are obtained solving the linear equation set constituted by using the EAR coefficients acquired in the first step. Finally, the autoregressive parameters of the 2-D ARMA model are found by exploiting the values obtained in first and second steps. The performance of the proposed algorithm is compared with other 2-D ARMA parameter and spectral estimation algorithms available in the technical literature by means of three different criteria. As a result of this comparison, it is shown that the parameters and the corresponding power spectrums estimated by using the proposed algorithm are converged to the original parameters and the original power spectrums, respectively. 相似文献
98.
José L. Arco-Tirado Francisco D. Fernández-Martín Juan-Miguel Fernández-Balboa 《Higher Education》2011,62(6):773-788
The purposes of this study were, on one had, to determine the impact of a peer tutoring program on preventing academic failure
and dropouts among first-year students (N = 100), from Civil Engineering, Economics, Pharmacy, and Chemical Engineering careers; while, on the other hand, to identify
the potential benefits of such tutoring program on the cognitive and metacognitive learning strategies and social skills of
student mentors in their last year of studies or already in a postgraduate program (N = 41) at the University of Granada (Spain). After building and selecting the measurement instruments necessary to gather
demographic and academic relevant information on both samples, and assigning first-year students to either an experimental
or control group, the intervention consisted of ten 90-min tutoring sessions during the first semester lead by student tutors
who, in turn, had undergone four 3-h training sessions on tutoring contents like planning and time management, cognitive and
metacognitive learning strategies, motivational strategies and the use of materials designed ad hoc for this program. The results show differences in favour of the treatment group on grade point average, performance rate,
success rate and learning strategies and, also, statistically significant pre-post differences for the tutors on learning
strategies and social skills. 相似文献
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