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11.
This study investigated whether the presence of learning disabilities (LD) at age 10 was related to later schooling, employment, income, receipt of public aid, involvement in crime, and feeling of victimization at ages 21 and 24. Confidential self-report data were collected in a prospective, longitudinal panel study from a sample of 571 students, of whom 60 (10.5%) were children with LD. After controlling for gender, ethnicity, and socioeconomic status, the following results were obtained: The highest postsecondary school attainment for young adults with LD was not significantly different from that of their peers without LD, both at age 21 and age 24. The rate of employment and amount of earned income of young adults with LD were not significantly lower than those of their peers without LD both at age 21 and age 24. Young adults with LD were not significantly different from their peers without LD at age 21 and age 24 with respect to having children, but young adults with LD received significantly more public aid (such as food stamps, supplemental security income, and unemployment compensation) at age 21 but not at age 24. Young adults with LD were not significantly different from their peers without LD in committing crimes or feeling victimized at age 21 and age 24.  相似文献   
12.
In this paper, a semantic categorization method in generic home photos is proposed. In recent years, the semantic categorization of image has been a challenge due to the proliferation of digital home photos. Our approach is to detect semantically meaningful concepts contained in a photo. The proposed method incorporates an intermediate level of concepts, called local concept, so that it catches well semantic meaning of local regions of image as bridging the semantic gap of the low-level features and high-level category concepts. To detect the local concepts from the home photo, region segmentation by photographic region template and concept merging is also proposed. The efficacy of the proposed semantic categorization method was demonstrated with 3828 general home photos. The experiment results showed the proposed categorization method would be useful to detect multiple semantic meaning of the home photos.  相似文献   
13.
为促进亚洲各国之间的科技信息资源共享和科研合作,在这些区域内,通过一站式服务获取相关信息至 关重要。3 年前,基于谅解备忘录(MOU),中国科学技术信息研究所(ISTIC)、日本科学技术振兴机构(JST)及韩国 科学技术信息研究院(KISTI)建立了基于现有DOI 系统的长期合作机制。首先概要介绍分别由三机构运行管理的各自 国家的DOI 系统,以及三国之间的国际合作进展。然后,通过引入云服务平台的概念,提出未来的合作框架,以进一 步促进资源共享。  相似文献   
14.
Flash mobs are new, emerging, and evolving social phenomena that have recently been associated with youth violence in the US cities. The current study explores how youth understand flash mobs through focus groups conducted in Kansas City, Missouri (a site of violent youth flash mobs). Results indicate that youth have varying familiarity with flash mobs and define them in different ways; that youth perceive youth boredom to be the most frequent cause of problems with flash mobs; that youth connect ongoing social disorder with the violence associated with flash mobs; and that while social media are facilitators of flash mobs, flash mobs have their roots in youth activities that have been going on for generations (e.g., hanging out in groups and cruising). Results illustrate the importance of conducting formative research with youth, particularly about emergent phenomena, when developing interventions and communication campaigns aimed at reducing youth violence.  相似文献   
15.
DIMTEST is a widely used and studied method for testing the hypothesis of test unidimensionality as represented by local item independence. However, DIMTEST does not report the amount of multidimensionality that exists in data when rejecting its null. To provide more information regarding the degree to which data depart from unidimensionality, a DIMTEST-based Effect Size Measure (DESM) was formulated. In addition to detailing the development of the DESM estimate, the current study describes the theoretical formulation of a DESM parameter. To evaluate the efficacy of the DESM estimator according to test length, sample size, and correlations between dimensions, Monte Carlo simulations were conducted. The results of the simulation study indicated that the DESM estimator converged to its parameter as test length increased, and, as desired, its expected value did not increase with sample size (unlike the DIMTEST statistic in the case of multidimensionality). Also as desired, the standard error of DESM decreased as sample size increased.  相似文献   
16.
The purpose of the study was to examine whether gender differences exist in the mean levels of and relations between adolescents’ home environments (parents’ view of science, socio-economic status (SES)), motivations (intrinsic and instrumental motivations, self-beliefs), and pursuit of science careers. For the purpose, the Programmed for International Student Assessment 2006 data of Korean 15-year-old students were analysed. The results of the study showed that girls had lower levels of science intrinsic and instrumental motivations, self-beliefs, and science-career pursuit (SCP) as well as their parents’ values in science less than boys. Gender similarities, rather than gender differences, existed in patterns of causal relationship among home environments, motivations, and SCP. The results showed positive effects for parents’ higher value in science and SES on motivations, SCP, and for intrinsic and instrumental motivations on SCP for girls and boys. These results provide implications for educational interventions to decrease gender differences in science motivations and SCP, and to decrease adolescents’ gender stereotypes.  相似文献   
17.
Calibration and equating is the quintessential necessity for most large‐scale educational assessments. However, there are instances when no consideration is given to the equating process in terms of context and substantive realization, and the methods used in its execution. In the view of the authors, equating is not merely an exhibit of the statistical methodology, but it is also a reflection of the thought process undertaken in its execution. For example, there is hardly any discussion in literature of the ideological differences in the selection of an equating method. Furthermore, there is little evidence of modeling cohort growth through an identification and use of construct‐relevant linking items’ drift, using the common item nonequivalent group equating design. In this article, the authors philosophically justify the use of Huynh's statistical method for the identification of construct‐relevant outliers in the linking pool. The article also dispels the perception of scale instability associated with the inclusion of construct‐relevant outliers in the linking item pool and concludes that an appreciation of the rationale used in the selection of the equating method, together with the use of linking items in modeling cohort growth, can be beneficial to the practitioners.  相似文献   
18.
Gold nanoparticles (Au NPs) were directly synthesized on the surface of polyvinylsilazane (PVSZ, -[(vinyl)SiH-NH2]-) without use of extra reductive additives. The reductive Si-H functional groups on the surface of cured PVSZ acted as surface bound reducing agents to form gold metal when contacted with an aqueous Au precursor (HAuCl4) solution, leading to formation of Au NPs adhered to silicate glass surface. The Au NPs-silicate platforms were preliminarily tested to detect Rhodamine B (1 μM) by surface enhanced Raman scattering. Furthermore, gold microelectrode obtained by post-chemical plating was used as an integrated amperometric detection element in the polydimethylsilane-glass hybrid microfluidic chip.  相似文献   
19.
Wind tunnel experiments were conducted, in particular focusing on slow unsteady variations of aerodynamic forces as a potential cause of the knuckle effect of a new soccer ball (Teamgeist) under non-spinning condition. The experiments included simultaneous measurements of the drag, the side force and the surface pressure on a ball surface, and the tuft visualisation to investigate the flow field behind a ball. Of particular interest was the erratic nature of the knuckle effect resulting from the unsteady movement of vortical wake structure in the supercritical Reynolds number regime. A simple 2-D numerical simulation of the ball flight trajectory was performed by taking into account the unsteady side force data measured in the present experiments.  相似文献   
20.
Both general and domain-specific search engines have adopted query suggestion techniques to help users formulate effective queries. In the specific domain of literature search (e.g., finding academic papers), the initial queries are usually based on a draft paper or abstract, rather than short lists of keywords. In this paper, we investigate phrasal-concept query suggestions for literature search. These suggestions explicitly specify important phrasal concepts related to an initial detailed query. The merits of phrasal-concept query suggestions for this domain are their readability and retrieval effectiveness: (1) phrasal concepts are natural for academic authors because of their frequent use of terminology and subject-specific phrases and (2) academic papers describe their key ideas via these subject-specific phrases, and thus phrasal concepts can be used effectively to find those papers. We propose a novel phrasal-concept query suggestion technique that generates queries by identifying key phrasal-concepts from pseudo-labeled documents and combines them with related phrases. Our proposed technique is evaluated in terms of both user preference and retrieval effectiveness. We conduct user experiments to verify a preference for our approach, in comparison to baseline query suggestion methods, and demonstrate the effectiveness of the technique with retrieval experiments.  相似文献   
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