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111.
Cognitive theory suggests that a key to expert performance lies in the internal organization of the expert's knowledge. The authors contend that the type of technical illustration used during instruction influences knowledge organization and greatly impacts students' understanding of the content. This paper describes an experimental study that tested the impact of one type of conceptual illustration on students' understanding of the structure, function, and behavior of complex technical systems. The results show that supplementing traditional technical instruction with functional flow diagrams can improve overall system understanding. The functional flow diagrams were also found to be an effective instructional aid for enhancing students' conceptual understanding of the causal behavior of systems. In addition, the use of the functional flow diagram was found to significantly improve the subjects' ability to construct conceptual models that were similar to those of an expert. The implications of using conceptual diagrams for technical instruction are discussed and recommendations for future research in this area are provided.  相似文献   
112.
Factors associated with one-year retention in a community college   总被引:1,自引:0,他引:1  
This study sought to evaluate preenrollment variables as predictors of one-year retention of first-time students in a community college. The purpose was to use information that is typically available when a student begins his or her college program and determine if this information can help identify students who are more likely to drop out within their first year. Based on a logistic regression model to select predictors of retention, the lower the high school GPA, the greater the chance the student will drop out. Over and above this, additional risk is associated with the age range 20–24, attending part-time, and being an ethnic minority other than Asian. When all or some of these are operating, it may be necessary to enhance these students' chances with special programs or services.  相似文献   
113.
Abstract

The study focused on constraints affecting the utilization of Information and Communication Technologies (ICT) for agricultural extension activities by Agricultural Extension Officers in Nigeria's Niger Delta Region. Data were derived from 160 extension officers affiliated to both public and private extension organizations in four states of the Niger Delta. Findings revealed important specific constraints to include: poor ICT infrastructure development, high cost of broadcast equipment, high charges for radio/television presentations, high cost of access/interconnectivity and electricity power problems. The use of Factor Analysis aided to crystallize identified constraints into three factors of ‘poor enabling environment’, ‘lack of access’ and ‘dissemination of unrelated information’. Against the background of several national government initiatives to develop the infrastructure base of the country, recommendations are proffered to ameliorate ICT use constraints.  相似文献   
114.
Abstract

One of the major impediments for diversification of groundnut (Arachis Hypogaea L.) as food crop is aflatoxin contamination. The study was conducted with an objective to assess the adoption gaps in aflatoxin management practices of groundnut (AMPG) and the farmer's characteristics influencing these gaps. The study used an expost-facto research design and multi-stage random sampling. The data were collected from 180 respondents through interview schedule. For measuring adoption gap, knowledge of AMPG and perception of groundnut quality suitable scales were developed. The data were subjected to multiple regression analysis to know the characteristics, which influenced the adoption gaps in AMPG. The majority of farmers were in high adoption gap category, as most of the farmers had not adopted the harvest and post-harvest management practices. Farmers' characteristics such as knowledge, market orientation and innovativeness influenced the adoption gap significantly. These three variables put together explained 58% of variation in adoption gap. Based on the results, it is suggested to formulate strategies to increase the knowledge of farmers through various extension approaches. If the knowledge on AMPG is improved the adoption gaps can be reduced. The maiden research effort, shed light on the socio-economic dimensions of aflatoxin contamination and constraints for aflatoxin management at farmers' level. The study has significance for the policy makers, extension departments and groundnut farmers for production of quality groundnut.  相似文献   
115.
Inclusion of race and gender in criminal justice education has, to some degree, been prompted as a result of perceived bias by criminal justice system professionals. Utilizing the race and gender experience as a template, interactions between the gay, lesbian, bisexual and transgendered (GLBT) community and the criminal justice system are explored. This study surveyed criminal justice undergraduate degree programs to ascertain course content on gay and lesbian issues. Results indicate that an extremely small number of programs have such a course or alternatively incorporate GLBT issues within existing race and gender courses. Implications for criminal justice education are discussed.  相似文献   
116.
In 2005 the Academy of Criminal Justice Sciences approved ACJS Certification Standards for Academic Programs. This was the culmination of two decades of efforts on the part of criminal justice educators to establish minimum standards for the discipline. These standards were developed to improve the quality of criminal justice education at the associate’s, bachelor’s and master’s degree levels. Section C, which establishes faculty qualifications for teaching at the various program levels, has been criticized by educators holding JDs as an effort by PhDs to push them out of the profession. The President of the Academy of Criminal Justice Sciences responds to specific concerns of JDs and then discusses the general impacts of the ACJS certification standards on criminal justice education.  相似文献   
117.
ABSTRACT

In a quasiregular orthography like English, children inevitably encounter irregular words during reading. Previous research suggests successful reading of an irregular word depends at least partially on a child’s ability to address the mismatch between decoded form and stored word pronunciation, referred to as a child’s set for variability, and the word’s relative transparency, measured here using a spelling to pronunciation transparency rating. Item-level analyses were used to explore the relationship between general child performance on the set for variability mispronunciation task, word specific set for variability (predicting reading of that word), spelling to pronunciation transparency rating, and irregular word reading. Significant predictors included general word reading, general set for variability performance, and item-specific set for variability performance; word frequency and spelling to pronunciation transparency rating; and an interaction between word reading and the transparency rating. Results underscore the importance of considering both general and item-specific factors affecting irregular word reading.  相似文献   
118.
ABSTRACT

We investigated students’ perceptions related to psychological constructs in their science classes and the influence of these perceptions on their science identification and science career goals. Participants included 575 middle school students from two countries (334 students in the U.S. and 241 students in Iceland). Students completed a self-report questionnaire that included items from several measures. We conducted correlational analyses, confirmatory factor analyses, and structural equation modelling to test our hypotheses. Students’ class perceptions (i.e. empowerment, usefulness, success, interest, and caring) were significantly correlated with their science identification, which was correlated positively with their science career goals. Combining students’ science class perceptions, science identification, and career goals into one model, we documented that the U.S. and Icelandic samples fit the data reasonably well. However, not all of the hypothesised paths were statistically significant. For example, only students’ perceptions of usefulness (for the U.S. and Icelandic students) and success (for the U.S. students only) significantly predicted students’ career goals in the full model. Theoretically, our findings are consistent with results from samples of university engineering students, yet different in some ways. Our results provide evidence for the theoretical relationships between students’ perceptions of science classes and their career goals.  相似文献   
119.
Abstract

In 1988 the Open University is implementing a major new policy on the use of computers in its courses; students taking certain courses will be obliged to have access to a microcomputer. This new policy has many far‐reaching consequences, not least for students who are disabled. In the past most computing in Open University courses has been done by students using terminals in local study centres, linked to the University's mainframe computers. Also, a number of students who are disabled have used computers in their studies, principally for word‐processing written work. By interviewing disabled students who have taken such courses, and surveying other disabled students, it has been possible to anticipate to some extent the likely impact of the home‐computing (HC) policy. Results suggest that for many disabled‐ students the HC policy represents an improvement in their opportunities; now they will be able to study courses involving computers entirely at home. However, a number of problems have also been identified. Hopefully, as many of these have been recognised at an early stage, it will be possible to address them before they affect students directly.  相似文献   
120.
The relative importance of mental effort, as indicated by strategy use, and persistence as potential mediators of the memory self-efficacy (MSE)/memory performance relationship was investigated within a sample of 26 adults aged 65 years and older. It was found that persistence but not strategy use was predictive of performance on a free-recall task. Age-related declines were found in persistence, performance, and MSE but not in strategy use. Counter to expectation, neither strategy use nor persistence was significantly related to a global measure of MSE. These results highlight the importance in MSE research of distinguishing mental effort and persistence, of task-specific measures of MSE, and of considering age-related changes within the elderly population. Implications for MSE intervention programs are briefly discussed.  相似文献   
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