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991.
V.L.Krupenin 《出版与印刷》2015,(1)
In this paper in general the dynamic effects are considered and described, caused by different stand-ing waves in discrete and distributed systems with impacts and other strongly positional non-linear fac-tors, introduction of which in the models of me-chanical objects is dictated by the necessity to con-sider processes, accompanied with impacts of me-chanical subsystems of different nature. 相似文献
992.
用不同于已有文献的方法研究了一类高阶中立型微分方程,本文不需要条件f∞t0Q(s)ds=∞,获得了这类方程振动性的几个新的结果. 相似文献
993.
Leonardo Madariaga Miguel Nussbaum Faustino Marañón Cristóbal Alarcón María Alicia Naranjo 《Government Information Quarterly》2019,36(2):179-195
People still use documents in many everyday government processes. From tax payments to passport requests, citizens have to interact with low-interactivity information artifacts such as reports, maps and datasets, among many others. Despite efforts to improve information delivery in the public sector, effective information usage remains a critical topic of action and research. The user experience of government documents has rarely been assessed, despite them being regularly published and frequently used. Considering this, the two following research questions arise: 1) How can government documents be classified (or grouped) in terms of user experience? 2) How can the user experience of government documents be monitored over time in order to inform design decisions? Working with a public agency in Chile, we develop and test a classification and monitoring framework based on two online surveys (N?=?338 and N?=?298). We then propose a framework for understanding user experience of government documents in these three dimensions: interaction goal, volume of information and ease of understanding. Using a graphical representation to classify user experience provides greater visibility of the current status of information produced by a public organization. Furthermore, by monitoring the user experience of a government document at different times, organizations can understand the effect of their design decisions and improve their service quality by implementing user-centered processes. 相似文献
994.
Méndez A Pérez C Montañéz JC Martínez G Aguilar CN 《Journal of Zhejiang University. Science. B》2011,12(12):961-968
The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture
of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature
levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and
a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining
natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L). 相似文献
995.
Ruszkowska B Gadomska G Bielis L Gruszka M Góralczyk B Rość D Odrowąż-Sypniewska G 《Journal of Zhejiang University. Science. B》2011,12(1):12-17
Objective
The influence of hormone replacement therapy (HRT) on hemostasis processes depends on the type of hormone, the combination of doses, the time of taking HRT, and the route of administration (oral, transdermal, implanted). The aim of the current study was to assess some parameters of coagulation, especially tissue factor pathway inhibitor (TFPI) and tissue factor (TF) in postmenopausal women using oral or transdermal HRT. 相似文献996.
997.
During economic development, modern museums face competition from various leisure activities and entertainment sites, and to achieve sustainable development, museums should reflect on providing high‐quality service to satisfy visitors’ expectations. Based on service design‐related theories, this research team conducted a case study to explore the planning, implementation, and meaning of Mobile Museums. It investigated design development from the perspective of public service design and summarized the policy, design, and service satisfaction results for Mobile Museums. Finally, the similarities in service processes are discussed between Mobile Museums and the general service industry. According to this study, attracting more visitors is the biggest issue facing museums today, as are the ways in which museums must actively provide service and become recognized to compete with others. This study identifies the onstage and backstage support of museums as well as their cultural features and non‐profit services. 相似文献
998.
Katrina Ferrara Kathy Hirsh‐Pasek Nora S. Newcombe Roberta Michnick Golinkoff Wendy Shallcross Lam 《Mind, Brain, and Education》2011,5(3):143-151
Spatial skills are a central component of intellect and show marked individual differences. There is evidence that variations in the spatial language young children hear, which directs their attention to important aspects of the spatial environment, may be one of the mechanisms that contributes to these differences. To investigate how play affects variations in language, parents and children were assigned to 1 of 3 conditions: free play with blocks, guided play, or play with preassembled structures (Study 1). Parents in the guided play condition produced significantly higher proportions of spatial talk than parents in the other two conditions, and children in the guided play condition produced significantly more spatial talk than those in the free play condition. Study 2 established baselines of spatial language during activities not involving spatial materials. Proportions of spatial words were lower than those in any of the conditions of Experiment 1. In sum, interaction with blocks naturally elicits elevated levels of spatial language, especially in the context of guided play, suggesting simple‐to‐execute educational interventions. 相似文献
999.
Virginia L. J. Bolshakova Carla C. Johnson Charlene M. Czerniak 《Cultural Studies of Science Education》2011,6(4):961-997
In the United States today, urban schools serve the majority of high-poverty and high minority populations including large
numbers of Hispanic students. While many Hispanic students perform below grade level in middle school science, the science
teaching community as a whole is lacking elements of diversity as teachers struggle to meet the needs of all learners. Researchers
have recognized that science teacher effectiveness, one consequence of self-efficacy among teachers, is associated with future
science achievement and science-related careers of their students. This qualitative study explores how three science teachers’
effectiveness in the classroom impacts students’ science self-efficacy beliefs at one urban middle school. Hispanic students
were the focus of this investigation due to demographics and history of underperformance within this district. Teachers’ perspectives,
as well as outside observer evaluations of instructional strategies and classroom climates were triangulated to explore dynamics
that influence students’ interests and motivation to learn science using a framework to link teachers’ sense of efficacy (focusing
on student outcomes). Findings suggest the impact teacher effectiveness can have on student outcomes, including strengthened
student science self-efficacy and increased science achievement. Building awareness and support in teachers’ sense of efficacy,
as well as developing respectful and supportive relationships between educator/facilitator and pupil during the transition
to middle school may construct permanence and accomplishment for all in science. 相似文献
1000.
Science education in the United States will increasingly be driven by testing and accountability requirements, such as those mandated by the No Child Left Behind Act, which rely heavily on learning outcomes, or "standards," that are currently developed on a state-by-state basis. Those standards, in turn, drive curriculum and instruction. Given the importance of standards to teaching and learning, we investigated the quality of life sciences/biology standards with respect to genetics for all 50 states and the District of Columbia, using core concepts developed by the American Society of Human Genetics as normative benchmarks. Our results indicate that the states' genetics standards, in general, are poor, with more than 85% of the states receiving overall scores of Inadequate. In particular, the standards in virtually every state have failed to keep pace with changes in the discipline as it has become genomic in scope, omitting concepts related to genetic complexity, the importance of environment to phenotypic variation, differential gene expression, and the differences between inherited and somatic genetic disease. Clearer, more comprehensive genetics standards are likely to benefit genetics instruction and learning, help prepare future genetics researchers, and contribute to the genetic literacy of the U.S. citizenry. 相似文献