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关键词： Computing identity   computer science   STEM career choice  

摘要： This paper expands on knowledge of computing identity by building on what is known about prior identity models in science and mathematics education. The model theorizes three primary sub-constructs that contribute to the development of a computing identity: belief in one's performance/competence, interest, and recognition in computing. Drawing on data from a nationally representative survey of more than 1,700 college students at 22 colleges and universities, the study tested the alignment of the theorized model to the measures on the survey. Confirmatory Factor Analysis was used to validate whether the appropriate measures loaded on the three separate sub-constructs. Criterion-related validity was also established by testing whether the computing identity measures predicted the choice of a computer science career. The results reveal that a computing identity proxy based on the theorized measures was a highly significant predictor of students' computer science and information technology career choice (p < 0.0001). In addition, this work also established criterion-related validity by showing gender differences that had been found by prior work in computing. Finally, the theorized measures were found to be reliable and internally consistent. The educational understanding of computing identities may provide an important tool to help researchers and practitioners improve student persistence in computer science.

摘要： Empowering communities through citizen science.

关键词： K12   Scratch   abstraction   algorithmic design   introduction to computer science   black box  

摘要： The Abstraction is one of the most fundamental ideas in computer science (CS), and as such, according to Bruner [23], it should be taught spirally, starting as early as possible and revisited at every level of education. However, teaching CS abstraction to novices is a very challenging task, and CS educational research has often demonstrated students' difficulties in learning this idea, in different contexts and at different age levels. The challenge in teaching CS abstraction is even greater when dealing with young students, since according to theories on children's cognitive development, their abstraction abilities may still be not fully developed. In 2013, Armoni [5] introduced a framework for teaching abstraction in the context of algorithmic problem solving, intended for novice students. We studied the effect of this framework in an introductory CS course for 7th graders, in which Scratch was used as the programming language for implementing algorithmic solutions. Our findings indicate that the framework was highly effective for developing CS abstraction skills as well as other related skills and aspects, such as the tendency to provide explanations for solutions, the use of initialization processes, and the perception of the nature of CS. It also significantly improved students' general CS performance in this course.

关键词： Computer science   Cancer prevention   Prediction tool   Lung symptoms   Lung cancer   Risk factors  

摘要： Background: Lung cancer is one of the deadliest cancer in the world. Hundreds of researches are presented annually in the field of lung cancer treatment, diagnosis and early prediction. The current research focuses on the early prediction of lung cancer via analysis of the most dangerous risk factors. Methods: A novel tool for the early prediction of lung cancer is designed following three stages: the analysis of an international cancer database, the classification study of the results of local medical questionnaires and the international medical opinion obtained from recently published medical reports. Results: The tool is tested using local medical cases and the local medical opinion(s) is (are) used to determine the accuracy of the scores obtained. The Machine Learning approaches are also used to analyze 1000 patient records from an international dataset to compare our results with the international ones. Conclusions: The designed tool facilitates computing the risk factors for people who are unable to perform costly hospital tests. It ds not require entering all risk inputs and produces the risk factor of lung cancer as a percentage in less than a second. The comparative study with medical opinion and the performance evaluation have confirmed the accuracy of the results.

关键词： Student-generated drawing   Imagination   Multimedia learning   Generative learning   Learning outcomes   Cognitive load   Spatial ability   Prior knowledge  

摘要： The purpose of this study was to examine the effects of student-generated drawing and imagination on learning recall, learning transfer, and cognitive load, and also students' attitudes towards the learning strategies when learning a computer-based science text, compared to learning with provided pictures. The study used three groups: drawing group, imagining group, and picture group (control). A total of 82 undergraduate students from a southeast university in the United States participated in this study. Results indicated there were no significant differences in the learning recall and transfer of the three groups overall;however, students' prior knowledge and spatial ability were positively and significantly correlated with their learning recall and transfer. When spatial ability was high, students in the drawing group had significantly higher learning recall than students in the imagining group;and students in the imagining group had significantly higher learning transfer than students in the picture group. The drawing group had significantly higher cognitive load than the picture group. Students perceived drawing, imagining, and reading with pictures for learning as useful and there were no significant differences in their perceived usefulness among the three groups, but students were more intended to learn with provided pictures than to generate drawings. Discussions and implications are provided.

关键词： Survey research   diversity   broadening participation   women and computing  

摘要： While demand for computer science and information technology skills grows, the proportion of women entering computer science (CS) fields has declined. One critical juncture is the transition from high school to college. In our study, we examined factors predicting college persistence in computer science- and technology-related majors from data collected from female high school students. We fielded a survey that asked about students' interest and confidence in computing as well as their intentions to learn programming, game design, or invent new technology. The survey also asked about perceived social support from friends and family for pursuing computing as well as experiences with computing, including the CS Advanced Placement (AP) exam, out-of-school time activities such as clubs, and internships. Multinomial regression was used to predict persistence in computing and tech majors in college. Programming during high school, taking the CS Advanced Placement exam, and participation in the Aspirations awards program were the best predictors of persistence three years after the high school survey in both CS and other technology-related majors. Participation in tech-related work, internships, or after-school programs was negatively associated with persistence, and involvement with computing sub-domains of game design and inventing new applications were not associated with persistence. Our results suggest that efforts to broaden participation in computing should emphasize education in computer programming.

关键词： Companies   Industries   Computer science   Marine vehicles   Proposals   Monitoring   Engineering students   Capstone projects   computer science   internships   supervision   workplace  

摘要： Contribution: Internships designed to provide training and an initial period of contact with industry, prior to a computer science engineering capstone project, have a very positive impact on both industry and academic capstone projects. Background: Internships and capstone projects are widely used to integrate work-related learning in computer engineering curricula. Both activities offer numerous benefits for students, industry, and academia. Although their effects have been extensively studied separately, the interaction between them remains unexplored. Research Questions: What is the effect of internships on the development of a subsequent capstone project? Methodology: The hypothesis was that the completion of an internship will have positive effects on several aspects of the capstone projects: 1) improved student competencies;2) improved capstone project outcomes;and 3) decreased supervision effort. Further, these positive effects were expected to be greater in industry-based projects than in academic projects. The hypothesis was tested through a quantitative study of data collected from 274 computer science engineering capstone projects. A period of time with internships was compared with another period without internships, and differentiating between academic and industry projects. Findings: Internships prior to capstone projects improve student skills in autonomy, technology, methodology, and project management;increase the complexity and technological novelty of the resulting projects;and reduce advisor involvement in practical (technology, execution) and keep-the-project-alive issues, and increase advisor involvement in monitoring student work (meetings, reports, and initial arrangements). This effect was observed in both industrial and academic projects.

关键词： Computer science   Random access   Distributed Bitmap Index   Star Join   Low-selectivity queries   Hadoop ecosystem  

摘要： Indices improve the performance of relational databases, especially on queries that return a small portion of the data (i.e., low-selectivity queries). Star joins are particularly expensive operations that commonly rely on indices for improved performance at scale. The development and support of index-based solutions for Star Joins are still at very early stages. To address this gap, we propose a distributed Bitmap Join Index (dBJI) and a framework-agnostic strategy to solve join predicates in linear time. For empirical analysis, we used common Hadoop technologies (e.g., HBase and Spark) to show that dBJI significantly outperforms full scan approaches by a factor between 59% and 88% in queries with low selectivity from the Star Schema Benchmark (SSB). Thus, distributed indices may significantly enhance low-selectivity query performance even in very large databases.

关键词： Biomedical engineering   Computer science   Electrical engineering   Medical imaging   Computer engineering   Signal processing   Image processing   Signal processing   Cross-spectral matching   Phase-based iris recognition   Band-limited phase-only correlation (BLPOC)   Phase-only correlation (POC)   Iris recognition  

摘要： In cross-spectral iris recognition, different spectral bands are used to obtain rich information of the human iris. Previous studies on cross-spectral iris recognition are based primarily on feature-based approaches, which are prone to the changes in parameters in the feature extraction process, such as spatial position and iris image acquisition conditions. These parameters can degrade iris recognition performance. In this paper, we present a phase-based approach for cross-spectral iris recognition using phase-only correlation (POC) and band-limited phase-only correlation (BLPOC). A phase-based iris recognition system recognizes an iris using the phase information contained in the iris image;therefore, its performance is not affected by feature extraction parameters. However, the performance of a phase-based cross-spectral iris recognition is strongly influenced by specular reflection. Different illumination conditions may produce different iris images from the same subject. To overcome this challenge, we integrate a photometric normalization technique-homomorphic filtering-with phase-based cross-spectral iris recognition. The experimental results reveal that the proposed technique achieved an excellent matching performance with an equal error rate of 0.59% and a genuine acceptance rate of 95%.

关键词： Deep learning   Artificial intelligence (AI)   Radiomics   Pancreatic ductal adenocarcinoma (PDA)   Pancreatic neuroendocrine tumor