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排序方式: 共有1004条查询结果,搜索用时 828 毫秒
1.
罗立祝 《机械工业高教研究》2008,(2):106-110
从高校招生的演变历史看,中国在1978年以前对工农阶层子女实行高校入学优惠政策主要源于国家对这一阶层的特殊偏好而实行平均主义分配政策所致。国家通过报考资格政策、优先录取政策和免试推荐入学政策人为地大幅度提高了工农阶层子女在高校大学生中所占的比例。从公平视角看,这项政策不仅违背了公平原则,而且降低了人才选拔的质量。 相似文献
2.
Prasad S Thenkabail Eden A Enclona Mark S Ashton Christopher Legg 《Remote sensing of environment》2004,90(1):23-43
The goal of this research was to compare narrowband hyperspectral Hyperion data with broadband hyperspatial IKONOS data and advanced multispectral Advanced Land Imager (ALI) and Landsat-7 Enhanced Thematic Mapper Plus (ETM+) data through modeling and classifying complex rainforest vegetation. For this purpose, Hyperion, ALI, IKONOS, and ETM+ data were acquired for southern Cameroon, a region considered to be a representative area for tropical moist evergreen and semi-deciduous forests. Field data, collected in near-real time to coincide with satellite sensor overpass, were used to (1) quantify and model the biomass of tree, shrub, and weed species; and (2) characterize forest land use/land cover (LULC) classes.The study established that even the most advanced broadband sensors (i.e., ETM+, IKONOS, and ALI) had serious limitations in modeling biomass and in classifying forest LULC classes. The broadband models explained only 13-60% of the variability in biomass across primary forests, secondary forests, and fallows. The overall accuracies were between 42% and 51% for classifying nine complex rainforest LULC classes using the broadband data of these sensors. Within individual vegetation types (e.g., primary or secondary forest), the overall accuracies increased slightly, but followed a similar trend. Among the broadband sensors, ALI sensor performed better than the IKONOS and ETM+ sensors.When compared to the three broadband sensors, Hyperion narrowband data produced (1) models that explained 36-83% more of the variability in rainforest biomass, and (2) LULC classifications with 45-52% higher overall accuracies. Twenty-three Hyperion narrowbands that were most sensitive in modeling forest biomass and in classifying forest LULC classes were identified and discussed. 相似文献
3.
According to J. F. Dovidio and S. L. Gaertner's (1998) integrated model of racism, politically liberal European Americans tend to express racism differently than conservative European Americans, with liberals demonstrating aversive racism and conservatives, symbolic or modern racism. In support of the model, in Experiment 1 liberals showed bias in favor of a twice-prosecuted African American relative to a European American in their judgment of double jeopardy, whereas conservatives did the reverse. Experiment 2 replicated these effects while eliminating a confound in the design of Experiment 1. Experiment 3 found evidence for the intrapsychic conflict hypothesized to underlie aversive racism. Specifically, only liberals displayed greater physiological arousal to the touch of an African American versus a European American experimenter. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Bray James H.; Adams Gerald J.; Getz J. Greg; McQueen Amy 《Canadian Metallurgical Quarterly》2003,71(3):553
The study used latent growth modeling to investigate longitudinal relationships between individuation, peer alcohol use, and adolescent alcohol use among African American, Mexican American, and non-Hispanic White adolescents (N=6,048) from 7th, 8th, and 9th grades over a 3-year period. Initial levels of peer alcohol use were significantly related to changes in adolescents' alcohol use, whereas initial adolescent alcohol use also significantly related to changes in peers' alcohol use, suggesting a bidirectional relationship. Higher levels of intergenerational individuation were related to smaller increases in adolescent alcohol use and higher levels of separation were related to larger increases in youth drinking. The findings were similar across ethnic groups. Implications for development of prevention and intervention programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Brody Gene H.; Ge Xiaojia; Kim Su Yeong; Murry Velma McBride; Simons Ronald L.; Gibbons Frederick X.; Gerrard Meg; Conger Rand D. 《Canadian Metallurgical Quarterly》2003,71(2):211
Data from 296 sibling pairs (mean ages 10 and 13 years), their primary caregivers, and census records were used to test the hypothesis that African American children's likelihood of developing conduct problems associated with harsh parenting, a lack of nurturant-involved parenting, and exposure to an older sibling's deviance-prone attitudes and behavior would be amplified among families residing in disadvantaged neighborhoods. A latent construct representing harsh-inconsistent parenting and low levels of nurturant-involved parenting was positively associated with younger siblings' conduct disorder symptoms, as were older siblings' problematic attitudes and behavior. These associations were strongest among families residing in the most disadvantaged neighborhoods. Future research and prevention programs should focus on the specific neighborhood processes associated with increased vulnerability for behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Eight hundred and fifty-two (852) blood sera were drawn in 1980 and 1981 from populations residing in 30 agricultural settlements (having a total population of 16,240). These sera were tested for the presence of antibodies against 15 different antigens of Legionella species (L. pneumophila serogroups 1–8 and seven other Legionella, i.e. bozemanii, gormanii, micdadei, jordanis, dumoffii, longbeacheae and oakridgensis). The results indicate a significant (P < 0.02) excess in the percentage of sera positive for L. pneumophila (serogroups 1–8) among sewage and non-sewage irrigation and fish pond workers as compared to the control group (4.5% vs 1.5%). For the other Legionella species, there was no difference among the above groups. The isolation of L. pneumophila serogroup 4 and five organisms resembling Legionella spp from one oxidation pond used for irrigation strengthens the seroepidemiological findings. 相似文献
7.
ObjectiveThis study aimed to assess the prevalence of neck pain and to identify associated occupational factors in Portuguese office workers.BackgroundThere is still necessary to quantify the association of the use of new technologies with neck pain in office workers.MethodsSix hundred-and-one office workers completed online questionnaires with questions related to anthropometric parameters, work-related variables, workstation setup, and musculoskeletal pain from the Portuguese version of the Standardized Nordic Musculoskeletal Questionnaire.ResultsThe prevalence of neck pain was 56.1%. An average of 35.6% of the office workers with neck pain reported pain in more than three body segments. The significantly risk factors were “age between 50 and 65” [OR: 1.92 (1.26–2.91) P = 0.002], “working without break for 2 h” [OR: 1.82 (1.00–3.31) P = 0.05], “more than 3 h” [OR: 2.41 (1.35–4.10) P = 0.003], screen localization not centered” [OR: 2.01 (1.01–4.00) P = 0.045], and “use of computer mouse more than 50% of the worktime” [OR: 2.05 (1.14–3.71) P = 0.017].ConclusionThere was a high prevalence of neck pain and a considerable number of painful body segments in office workers. Age, working without break, screen localization and the use of computer mouse where the significant risk factors associated with the development of neck pain.Relevance to industryA high prevalence of neck pain and number of areas with pain in office workers require a detailed pain mechanism assessment. There were associated occupational risk factors for the development of neck pain. Call for concerted actions to explore optimal and efficient management plans. 相似文献
8.
高支模工程安全管理不仅需要很高的技术,而且安全管理本身也具有较大的随机性,这就导致相关人员在开展安全管理工作时具有一定的难度。面对这一问题,相关监理人员必须从施工方案的审批、应急预案的落实、质量安全作业的施工技术交底和施工过程中所需要的各种原材料进场前的检验等方面加强管理。 相似文献
9.
赵炎 《北京建筑工程学院学报》2010,26(1):67-70,75
农民工权益问题是我国改革开放中涌现出来的众多主要社会问题之一.其中尤以建筑业农民工的权益保障问题最为突出.在研究农民工这一特殊群体的同时,以武汉市建筑业农民工为例分析、研究了建筑业农民工权益保障中存在的主要问题,提出了关于切实保障农民工合法权益的几点建议. 相似文献
10.
刘涛 《江汉石油职工大学学报》2010,23(1):20-22,26
在市场经济大潮中冲击下,企业政工干部队伍出现了后继乏人的尴尬局面。针对这种情况,要着手做要以下四个方面的工作:一是"造势",造有利于推进政工队伍建设的社会舆论;二是"补缺",搞好政工干部队伍的梯队建设;三是"外派",将政工干部放到改革的前沿阵地和艰苦环境中锻炼;四是"解忧",为政工干部解决后顾之忧。只有这样,才能保证企业政工干部队伍迅速健康成长。 相似文献