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81.
问答     
Q:在刚刚过去的2006财年,NetApp实现了28亿美元的销售额,同比增长36%,对存储领域的领头羊EMC保持了巨大压力。请问公司快速成长的秘诀是什么? A:关于我们为什么能取得近30亿美元的销售收入并成为这一个市场的领先者,大体上可以归结为三点,第一是因为我们正处于这个市场最黄金的  相似文献   
82.
The generality of S. K. Egan and D. G. Perry's (2001) model of gender identity and adjustment was evaluated by examining associations between gender identity (felt gender typicality, felt gender contentedness, and felt pressure for gender conformity) and social adjustment in 863 White, Black, and Hispanic 5th graders (mean age = 11.1 years). Relations between gender identity and adjustment varied across ethnic/racial groups, indicating that S. K. Egan and D. G. Perry's model requires amendment. It is suggested that the implications of gender identity for adjustment depend on the particular meanings that a child attaches to gender (e.g., the specific attributes the child regards as desirable for each sex); these meanings may vary across and within ethnic/racial groups. Cross-ethnic/racial investigation can aid theory building by pointing to constructs that are neglected in research with a single ethnic/racial group but that are crucial components of basic developmental processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
A study of the design of a sectored receiver structure that offers improved performance with respect to the main infrared channel parameters, such as path loss and rms delay spread, is presented. To this end, a model for the effective signal collection area of a sectored receiver is presented and validated that, through the use of a Monte-Carlo-based ray-tracing algorithm, allows us to obtain the channel impulse response. The simulation results presented show the effect of the orientation and field of view (FOV) of each sector on the quality of the received signal. On the basis of these results, the use of a sectored receiver, composed of three crowns of sectors with different vertical and horizontal FOVs, has been proposed that minimizes the multipath dispersion and power requirements.  相似文献   
84.
ZnO + Zn2TiO4 thin films were obtained by the sol–gel method using precursor solutions with different Ti/Zn ratios in the 0.18–2.13 range. The films were deposited on glass substrates and annealed in an open atmosphere at 550 °C. The oxide was characterized by X-ray diffraction and photoacoustic (PA) spectroscopy. The films were constituted of polycrystalline ZnO for the lowest Ti/Zn ratio (0.18), polycrystalline Zn2TiO4 for the 0.70 and 1.0 ratios, and mixes of both oxides for the intermediate ratios (0.32 and 0.50). For the highest ratios studied (1.44 and 2.13), the films were amorphous. The energy band gap (Eg) values were determined from optical absorption spectra, measured by means of the PA technique spectra. Eg varied in the 3.15 eV (ZnO) to 3.70 eV (Zn2TiO4) range.  相似文献   
85.
Intrinsic safety is a mature proven method to achieve a safe installation of electrical apparatus in a location made hazardous by the presence of flammable or combustible materials. Standards for intrinsically safe apparatus are still evolving. Underwriters' Laboratories, Inc. Standard 913-1975 and NFPA 493-1975 are the most c?omplete statement of requirements for intrinsically safe apparatus and systems yet published. The forthcoming Instrument Society of America Recommended Practice on installation of intrinsically safe systems will fill a pressing need for an installation guide. The National Electrical Code is also changing to recognize the needs of those in the process industries who use intrinsically safe systems and similar apparatus. Much yet needs to be done to define design constraints and Construction requirements for intrinsically safe apparatus. This work is underway.  相似文献   
86.
Owing to the dynamic nature of collaborative environments, the software intended to support collaborative work should adapt itself to the different situations that may occur. This requirement is related to the concept of “context of use”, which has been considered as an important aspect in the design of interactive systems. Nevertheless, two main problems about this concept have been identified by current research in context-aware computing: (1) most of the studies have mainly focused on the context of a single user, so the context of multiple users involved in a common endeavor remains little explored, and (2) adaptability in context-aware systems generally takes into account a reduced number of contextual variables (mainly the user’s location and platform). In this paper, we firstly re-conceptualize the notion of “context of use”, in order to consider the main characteristics of collaborative environments. Based on this new notion, we then design and implement a framework that allows application developers to specify the adaptability of groupware systems in terms of the state of activities, roles, collaborators’ location, available resources, and other typical variables of working groups. This framework has been generalized from scenarios that highlight dynamic situations presented in real collaborative settings. Finally, we validate our proposal by a set of applications that are able to adapt their user interface and functionality, when significant changes are produced in the environment, the working group, and/or the used devices.  相似文献   
87.
Democratization of genomics technologies has enabled the rapid determination of genotypes. More recently the democratization of comprehensive proteomics technologies is enabling the determination of the cellular phenotype and the molecular events that define its dynamic state. Core proteomic technologies include MS to define protein sequence, protein:protein interactions, and protein PTMs. Key enabling technologies for proteomics are bioinformatic pipelines to identify, quantitate, and summarize these events. The Trans-Proteomics Pipeline (TPP) is a robust open-source standardized data processing pipeline for large-scale reproducible quantitative MS proteomics. It supports all major operating systems and instrument vendors via open data formats. Here, we provide a review of the overall proteomics workflow supported by the TPP, its major tools, and how it can be used in its various modes from desktop to cloud computing. We describe new features for the TPP, including data visualization functionality. We conclude by describing some common perils that affect the analysis of MS/MS datasets, as well as some major upcoming features.  相似文献   
88.
To investigate the long-term trends and effects of decadal solar variability in the upper tropospheric ozone, data obtained from the Stratospheric Aerosol and Gas Experiment II (SAGE II) aboard the Earth Radiation Budget Satellite (ERBS) during the period 1985–2005 were analysed using a multifunctional regression model over the Indian region (8–40° N; 65–100° E). Analysis of time series spanning these years shows statistically insignificant trends (at the two-sigma level (95% confidence level)) at upper tropospheric pressure levels (10?16 km). This period covers two solar cycles, one lasting from 1985 to 1995 and the other from 1996 to 2005; these are referred to as decade I and decade II, respectively. Since temporal variation in ozone number density indicates 11 year periodicity, trends are statistically significant when calculated separately during each solar cycle. Trend analysis indicates statistically significant positive trends (0.7 ± 1.7% to 3.9 ± 2.9% year?1 during decade I, and 2.2 ± 1.6% to 4.5 ± 3.0% year?1 during decade II). In general, higher ozone trends are observed during decade II. Seasonal variation in trends during decade II shows increasing trends during the pre-monsoon (0.8?3.8% year?1), monsoon (0.8?7.1% year?1), and post-monsoon (2.8?8.0% year?1) seasons. The annually averaged solar signal in ozone is found to be of the order of around??5 ± 4.3% to??13.8 ± 6.7%/(100 sfu). Results obtained in the present study are also compared with those obtained by other researchers.  相似文献   
89.
Though major universities exert considerable influence on their communities, the specific dimensions of their economic impact are rarely appreciated. This study of the University of Colorado uses an input-output frameivork to estimate the effects of University operation on the local economy. Estimates are also furnished of University economic influence on the Denver metropolitan area and the state.  相似文献   
90.
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