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131.
132.
Presents an analysis of the attrition dilemma in psychotherapy research and reviews the methods used to compensate for data loss. It is argued that attrition is not ultimately a problem of bias but a problem of lack of information. A reformulation is offered that integrates single-case studies with traditional group comparison methodology in an attempt to find optimal causal relations of treatments to outcomes. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
133.
Giga Security     
The flow of information, within organizations, between networks, and from single users to other individuals and networks, is commonly at rates that only a few years ago were dreams. Earlier methods for the detection and prevention of malicious activities are anywhere from inefficient to unworkable with transmissions at the giga speeds that are prevalent today. This writing sets forth the problems and threats associated with these new high speed transmissions, and presents methodologies and systems for treating them.  相似文献   
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135.
One hypothesis for the transcontinental and intra-Great Lakes basin transfer of round gobies (Neogobius melanostomus) has been that round gobies were pumped into the ballast water of ships. During June 2005 in Lake Erie, we obtained evidence of a vertical migration of round goby larvae, when we collected 167 round goby larvae in surface ichthyoplankton net tows at night and zero during day. These results complemented similar findings from the Muskegon River estuary of Lake Michigan during 2003 and 2004, documenting diel vertical migration for the first time in larval round gobies. We suggest vertical migration behavior may have allowed larval round gobies to be transported to and within the Great Lakes via ballast water and dispersed in the Great Lakes via advection of 6.5–8.5-mm long larvae at the surface. Based on our results, if ballast water was only taken on near the surface during daylight hours from May through September when larval round gobies were present, it would have mitigated the spread of round gobies throughout the Great Lakes.  相似文献   
136.
The results of Stan ton and Bairstow (1908) have been reanalyzed to yield information on the composition dependence of the low cycle impact fatigue properties of pearlitic plain carbon steels. It has been found that the energy absorbed per impact, Ei, and the number of impacts are failure, Nf, are related by the equation: In this equation q is determined by the carbon, manganese and silicon contents of the steel; Eo is the impact endurance limit; and C and D are constants. The curve represented by this equation intersects that representing the Johnson-Keller high cycle impact fatigue equation at a value of logeNf equal to 1/C. Thus, the transition from low to high cycle impact fatigue occurs at this value of logeNf.  相似文献   
137.
Many spectral‐recovery methods using RGB digital cameras assume the underlying smoothness of illuminant and reflectance spectra, and apply low‐dimensional linear models. The aim of the present work was to test whether a direct‐mapping method could be used instead of a linear‐models approach to recover spectral radiances and reflectances from natural scenes with an RGB digital camera and colored filters. In computer simulations, a conventional RGB digital camera with up to three colored filters was used to image scenes drawn from a hyperspectral image database. Three measures were used to evaluate recovery with the direct‐mapping method: goodness‐of‐fit, root‐mean‐square error, and a color‐difference metric. It was found that with two and three filters both spectral radiances and reflectances could be recovered sufficiently accurately for many practical applications. With little increase in computational complexity, an RGB camera and a few colored filters can provide significantly better recovery of natural scenes than an RGB camera alone. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 352–360, 2007  相似文献   
138.
Replicated the 1st author and J. J. Parkington's (1979) research on the relationships between employees and customers in service organizations by analyzing survey data from 142 employees and 968 customers from 28 branches of a bank. Moderate support was found for the 1st author and Parkington's work on correlates of stress for boundary role employees. Support was also found for relationships between branch employees' and branch customers' service perceptions and attitudes as reported by the present 1st author et al (1980). Significant relationships were reported between branch employees' perceptions of organizational human resources practices and branch customers' attitudes about service. Employee attitudes and customer attitudes were related to their own and one another's turnover intentions. Results are discussed from the perspective of promoting an integration of consumer and organizational behavior in the service sector. (51 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
139.
With the increasing demand for a proper and efficient XML data storage, XML-Enabled Database (XEnDB) has emerged as one of the popular solutions. It claims to combine the pros and limit the cons of the traditional Database Management Systems (DBMS) and Native XML Database (NXD). In this paper, we focus on XML data update management in XEnDB. Our aim is to preserve the conceptual semantic constraints and to avoid inconsistencies in XML data during update operations. In this current era when XML data interchange mostly occurs in a commercial setting, it is highly critical that data exchanged be correct at all times, and hence data integrity in XML data is paramount. To achieve our goal, we firstly classify different constraints in XML documents. Secondly, we transform these constraints into XML Schema with embedded SQL annotations. Thirdly, we propose a generic update methodology that utilizes the proposed schema. We then implement the method in one of the current XEnDB products. Since XEnDB has a Relational Model as the underlying data model, our update method uses the SQL/XML as a standard language. Finally, we also analyze the processing performance.  相似文献   
140.
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