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1.
McWayne Christine M.; Fantuzzo John W.; McDermott Paul A. 《Canadian Metallurgical Quarterly》2004,40(4):633
The present concurrent study combined developmental and ecological considerations to examine the unique contribution of multiple preschool competencies to an indicator of early academic success. Participants included 195 Head Start children from 32 classrooms representative of a large, urban Head Start program. Dimensional (variable-centered) analyses revealed 3 distinct classroom competency dimensions (i.e., General Classroom Competencies, Specific Approaches to Learning, and Interpersonal Classroom Behavioral Problems). The first 2 of these dimensions were found to be uniquely associated with early academic success. Findings from typological (person-centered) analyses supported the dimensional findings. Typological analyses revealed 7 profiles of classroom competency distinguished by high scores on the dimensions of General Competencies and Approaches to Learning, and these profiles were found to relate differentially to the indicator of early academic success. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Stolorow Robert D.; Atwood George E.; Orange Donna M. 《Canadian Metallurgical Quarterly》2006,23(1):184
In omitting crucial words and sentencees, neglecting relevant citations, and overlooking important distinctions, Jon Mills' (see record 2005-04819-001) critique of relational psychoanalysis significantly misrepresents the authors' viewpoint. This viewpoint seeks to contextualize, but not to nullify, individual worlds of experience and their limiting horizons. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Per Hovstad Liching Sung 《International Journal of Satellite Communications and Networking》2005,23(2):91-110
The 1977 Broadcasting‐Satellite Service (BSS) Plan for Region 1 & 3 had been widely acknowledged to be out‐of‐date by the late 1980s. Development of digital modulation in the early 1990s provided an opportunity to update the technical provisions of the Plan to make it more economically viable. After a decade of work and three World Radiocommunication Conferences (WRCs), the revision of Region 1 & 3 BSS Plan was finally completed in 2003. The new Plan increased channel assignments from 5 to 10 analog‐equivalent channels for each country in Region 1, and from 4 to 12 channels for each country in Region 3. Yet, despite the increase in capacity, the new Plan is surprisingly similar to the original one in terms of the technical parameters. It is still based on national coverage, and the channel plan, orbital location, orbital spacing, and polarization are also the same. As a result, the new Plan is no more economically viable to implement than the old. To create economically viable BSS systems would most likely require modifications to the assignment in the Plan. Yet, modification procedures were made more difficult to apply after replanning. Less future implementation of BSS networks than would otherwise have occurred can be expected, and an inefficient usage of these frequency bands will likely result. On the other hand, less implemented systems will mean more capacity set aside for future use. This is important for countries that currently do not have satellite operations. In the end, BSS replanning reflects the eternal conflict between efficient usage and guaranteed future access. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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指出湖滨带是连接湖泊水体和陆地的一个功能过渡界面区。它作为生物的重要栖息地,具有净化水质、缓解波浪等多种功能。因此,对湖滨带实行生态恢复建设,应予以高度的重视。笔者通过具体工程的实践,阐述了湖滨带生态恢复建设工程的特点、施工阶段的监理工作,以及对监理人员的素质要求,可供类似工程借鉴、参考。 相似文献
6.
水生生物环境诊断(AOD)技术应用研究 总被引:4,自引:0,他引:4
介绍一种新型的毒性试验方法——水生生物环境诊断(AOD)技术,该方法将冷冻浓缩和生物测试技术有机地相结合,较好地解决了低毒性水体的毒性测试问题。应用本项技术以红鳍鱼为受试生物,分别对湖北武汉马伧湖、墨水湖、广东深圳河、长江干流寸滩等几个断面、丹江口水库白河、丹江河口、老灌河等不同水体进行AOD测试,所得48hr-LC\-50结果与实际水质状况基本相符。 相似文献
7.
Influences of land use/cover on water quality in the upper and middle reaches of River Njoro, Kenya 总被引:1,自引:0,他引:1
William A. Shivoga Mucai Muchiri Samuel Kibichi Jethro Odanga Scott N. Miller Tracy J. Baldyga Eric M. Enanga Maina C. Gichaba 《Lakes & Reservoirs: Research and Management》2007,12(2):97-105
Data from 10 sampling sites along the River Njoro are used to examine the contribution of nutrients from upstream land uses draining each of the sampling sites. The data also are used to assess whether both the proportion of land uses and the size of the subwatersheds account for the variability in water quality in the River Njoro watershed. Geographical Information System analysis was used to determine the spatial distribution of land‐cover types and subwatersheds contributing run‐off to the sampling sites in the River Njoro. Standard Digital Elevation Model‐based routines were used to establish the watershed area contributing run‐off to each sampling site. Water and sediment samples were collected for chemical analysis, and the nutrient levels were related to the upstream land‐use types and the size of the subwatersheds. The mid‐stream portion of the River Njoro (near Egerton University) accounts for the highest nutrient contributions. The percentage contribution is magnified by additions from industrial, human settlements and agricultural land uses around the University. There is a significant decrease in nutrient levels downstream, however, indicating natural purification as the river flows through an area of large‐scale farming with intense, well‐preserved riparian and in‐stream vegetation. Steep slopes of the land upstream of Egerton University enhance erosion and nutrient losses from those subwatersheds. Mixed small‐scale agricultural and bare lands contribute over 55% of the phosphorus load to the upper and mid‐reaches of the River Njoro. The size of the subwatershed accounts for about 53% of the variability in the soluble phosphorus in the river. The land‐use subwatershed proportions are important for characterizing and modelling water quality in the River Njoro watershed. Upland land uses are as important as near‐stream land uses. We suggest that conservation of intact riparian corridor along the river and its tributaries contributes significantly to natural purification processes and recovery of the ecological integrity of the River Njoro ecosystem. 相似文献
8.
人力资源管理中的人才资源管理是现代企业面临的一个重大挑战。国企中的人才资源管理需要不断进行观念创新,正确认识人才的流动,人才的识别选拔、人才的能上能下、人才的文化物质需求、人才的培育评价、人才的使用储备。 相似文献
9.
通过模型试验 ,对位于西安市东郊因采沙使河道破坏严重的灞河河段进行了复现试验和研究 ,并以此为依据 ,通过优化比较为设计部门提供了合理的橡胶坝坝址和坝座高程。在此基础上 ,又对建坝后橡胶坝对上下游冲淤变化的影响进行了试验研究和分析 ,解决了工程设计中的一些关键技术问题 相似文献
10.
Becker D. Vaughn; Kenrick Douglas T.; Neuberg Steven L.; Blackwell K. C.; Smith Dylan M. 《Canadian Metallurgical Quarterly》2007,92(2):179
Findings of 7 studies suggested that decisions about the sex of a face and the emotional expressions of anger or happiness are not independent: Participants were faster and more accurate at detecting angry expressions on male faces and at detecting happy expressions on female faces. These findings were robust across different stimulus sets and judgment tasks and indicated bottom-up perceptual processes rather than just top-down conceptually driven ones. Results from additional studies in which neutrally expressive faces were used suggested that the connections between masculine features and angry expressions and between feminine features and happy expressions might be a property of the sexual dimorphism of the face itself and not merely a result of gender stereotypes biasing the perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献