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81.
This paper demonstrates the application of module arithmetic for controlling the level of information security by a new technique referred as integer splitting. The basic definitions and concepts of the method are provided. The mathematical function of arising transformation is described in detail; its properties were studied and the basic theorems were proven that justify the use of splitting in practical applications. An active system was designed and characteristic cases of its operation are considered.  相似文献   
82.
ABSTRACT

North Carolina Central University (NCCU) recognized the need to address the increasing rates of Ds, Fs, and Withdrawal by students matriculating in online courses. Led by two science faculty, a faculty learning community in partnership with the NCCU Division of Extended Studies was created to assess online science course offerings and instruction. Faculty within this learning community completed the Quality Matters (QM) “Applying the Quality Matters Rubric” course. This online training course, coupled with services provided by the NCCU Division of Extended Studies, offered the faculty learning community a variety of pedagogical strategies to meet their instructional needs. All faculty participating in this learning community completed the online training course and all faculty indicated that they implemented changes in their subsequent online course offerings. This article describes the impact of that training and the application of quality course design standards in the Quality Matters Rubric on the design and student outcomes for an Introductory Biology course over four terms. As faculty learning communities are broadly utilized, it is anticipated that this article may present an effective strategy to increase the quality and quantity of online science, technology, engineering and mathematics (STEM) courses at similar institutions.  相似文献   
83.
The purpose of this investigation was to examine the efficacy of a new preschool oral language and early literacy curriculum package (Teaching Early Literacy and Language [TELL]) for children with developmental speech and/or language impairment (DSLI) either as a primary (e.g., specific to speech and/or language) or secondary impairment (e.g., developmental delay that includes DSLI). Participants included 118 children (30 females, 88 males, M age = 53.58 months) with DLSI and their 29 preschool teachers. The design was a randomized controlled trial (RCT) with assignment to experimental versus contrast conditions at the classroom level. Teachers in TELL classes received formal training, in-class support, and mentoring to implement the curriculum. Dependent measures for the children included scores on the Clinical Evaluation of Language Fundamentals-Preschool 2nd edition (CELF-P2), the Phonological Awareness Literacy Screening for Preschool (PALS-PreK), the Renfrew Bus Story (BUS), and a receptive and expressive vocabulary measure developed for this investigation (VOCAB). Results indicated that when compared to the contrast group, children in the TELL condition demonstrated greater gains on the phonological awareness subtest of the CELF-P2, the sentence length score of the BUS, the letter sounds, beginning sound awareness, and rhyme awareness subtests of the PALS-PreK, and VOCAB. Results suggest that the TELL curriculum package has promise for promoting gains in early literacy and oral language skills in preschool children with DLSI.  相似文献   
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In the article we solve path planning task for an agent being multirotor unmanned aerial vehicle (multicopter). We propose an approach of estimating path geometry constraints based on UAV flight dynamics model and control constraints. Than we introduce a new path finding method which takes into consideration those geometry constraints and study this method both theoretically and empirically.  相似文献   
87.
This study aimed to explore how children with learning disabilities (LD) perceive their quality of life (QoL) and to compare self‐reports and proxy reports regarding their QoL. Children with LD, their typically developing peers, their parents and teachers responded to the child, parent, and teacher forms of KINDLR Questionnaire for Measuring Health‐Related Quality of Life (Ravens‐Sieberer & Bullinger, 1998). Findings showed that children with LD reported significantly lower QoL scores than those reported by typically developing peers. Intraclass correlation coefficients (ICCs) and t‐test results showed that agreement between child reports and parent‐proxy reports was either low or moderate on each QoL dimension. Findings of the study may be used to raise awareness regarding the social and educational needs of children with LD in Turkey.  相似文献   
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89.
Soybean accounts for more than half of the global production of oilseed and more than a quarter of the protein used globally for human food and animal feed. Soybean domestication involved parallel increases in seed size and oil content, and a concomitant decrease in protein content. However, science has not yet discovered whether these effects were due to selective pressure on a single gene or multiple genes. Here, re-sequencing data from >800 genotypes revealed a strong selection during soybean domestication on GmSWEET10a. The selection of GmSWEET10a conferred simultaneous increases in soybean-seed size and oil content as well as a reduction in the protein content. The result was validated using both near-isogenic lines carrying substitution of haplotype chromosomal segments and transgenic soybeans. Moreover, GmSWEET10b was found to be functionally redundant with its homologue GmSWEET10a and to be undergoing selection in current breeding, leading the the elite allele GmSWEET10b, a potential target for present-day soybean breeding. Both GmSWEET10a and GmSWEET10b were shown to transport sucrose and hexose, contributing to sugar allocation from seed coat to embryo, which consequently determines oil and protein contents and seed size in soybean. We conclude that past selection of optimal GmSWEET10a alleles drove the initial domestication of multiple soybean-seed traits and that targeted selection of the elite allele GmSWEET10b may further improve the yield and seed quality of modern soybean cultivars.  相似文献   
90.
In each of two studies, teachers were randomly assigned to either a Virtual Workshop (VW) group that used a computerized professional development program or an Actual Workshop (AW) group that participated in face-to-face professional development, including discussion, feedback, and collaboration. In both studies, teachers’ posttest scores related to their knowledge of the Question Exploration Routine and their plans for using it were significantly higher than their pretest scores. In Study 2, both groups’ posttest scores with regard to implementation and planning of the routine were significantly greater than their pretest scores. There were no significant differences between the groups at posttesting on any measure. The posttest knowledge scores of the whole groups of students and the subgroups of students with LD being taught by both groups of teachers were significantly higher than their pretest scores. All teachers indicated that they were satisfied with the training and the routine. VW teachers in both studies indicated that they were satisfied with the software program.  相似文献   
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