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171.
This article investigates how culture shapes instruction in three early care and education programs on the Flathead Indian Reservation. Interviews with eight early childhood teachers as well as classroom observations were conducted. The investigation is framed by the following research question: How does the culture of the family and community shape curriculum? Data analysis suggested that ongoing communication with parents and community about teaching within a culturally relevant context, building a sense of belongingness and community through ritual, and respecting children, families, and community were essential to defining the Native American Indian culture within these early learning programs.  相似文献   
172.
In this paper, the effects of second-order difference-frequency wave forces on the global motion of an offshore wind turbine system with a large displacement under the survival condition are studied. In this case, the hydrodynamic force is the main force because the blades are feathered to reduce the lifting force. The first-order hydrodynamic forces are calculated by WADAM, while the second-order wave forces are calculated by a customized MATLAB module. Then the hydrodynamic coefficients are transferred to the wind turbine analytical code FAST. Through the comparisons of dynamic responses between the first- and second-order numerical models, it is found that the second-order wave forces significantly influence the motion of floating wind turbine under the survival condition. Moreover, neglecting the second-order force significantly underestimates the tension forces in the mooring lines.  相似文献   
173.
This paper focuses on a pattern design method for a 3D triangular garment surface. Firstly, some definitions of 3D style lines are proposed for designing the boundaries of patterns as drawing straight lines or splines on the triangular surface. Additionally some commonly used style lines are automatically generated to enhance design efficiency. Secondly, after style lines are preprocessed, a searching method is presented for quickly obtaining the boundaries and patches of a pattern on the 3D trian- gular surface. Finally a new pattern design reuse method is introduced by encoding/decoding the style line information. After style lines are encoded, the pattern design information can be saved in a pattern template and when decoding this template on a new garment surface, it automates the pattern generation for made-to-measure apparel products.  相似文献   
174.
The paper proposes a new method for computation of the Wigner-Ville distribution (WVD) taking account of the conjugate symmetry of the WVD kernel function and the periodicity and symmetry of the trigonometric function. The method transfers the computation of WVD into real field from complex field to remove the redundancies in the fast Fourier transform(FFT) computation. The realization of fast cosine operation and fast sine operation considerably reduces the computation cost. Theoretical analysis shows that  相似文献   
175.
The author asserts that the field of teacher education must begin a critical conversation to better prepare and support teachers in attending to the complexities of racialized identities, experiences, and perspectives of multiracial students in K12 schools. The author offers a review of literature relevant to multiracial students, and draws from the emerging theoretical framework of Multicrit (Harris in Int J Qual Stud Educ 29(6):795–813, 2016) to present monoracism, ahistoricism, colorism and intersectionality to analyze excerpts from three respective research studies. Each excerpt demonstrates an imperative to build a critical understanding of multiracial students within teacher work. The author concludes with implications for future research and practice.  相似文献   
176.
The co-benefit of hazardous trace elements such as mercury (Hg), arsenic (As), and selenium (Se) capture in dust removal devices of ultra-low emission coal-fired power plants was investigated. Feed fuel and ash samples collected from 15 different coal-fired power units equipped with ultra-low emission systems were characterized to determine the concentrations and distribution characteristics of trace elements. It was found that the low-low temperature electrostatic precipitator (LLT-ESP) and the electrostatic fabric filter (EFF) had greater abatement capacity for Hg than normal cold-side ESP (CS-ESP). Only 0.8%–36.1% of Hg escaped from LLT-ESP and EFF, whereas 42.1%–90.6% of Hg escaped from CS-ESP. With the employment of EFF and ESP (inlet temperature<125 °C), 72.3%–99.1% of As and 70.7%–100% of Se could be captured before the wet flue gas desulfurization (WFGD) system. The significance level of the effects on the abatement capacity for Hg, As, and Se in ESP were analyzed by the Pearson correlation analysis and grey relational analysis. The results indicated that the low inlet temperature of LLT-ESP had significant promotional effect on the simultaneous removal of Hg, As, and Se. The smaller particle size of fly ash can be conducive to the adsorption of hazardous trace elements. The inhibitory effect of sulfur content in coal was significant for the enrichment of Hg and Se in fly ash.  相似文献   
177.
178.
It is expected that by 2003 continuous media will account for more than 50% of the data available on origin servers, this will provoke a significant change in Internet workload. Due to the high bandwidth requirements and the long-lived nature of digital video, streaming server loads and network bandwidths are proven to be major limiting factors. Aiming at the characteristics of broadband network in residential areas, this paper proposes a popularity-based server-proxy caching strategy for streaming media. According to a streaming media popularity on streaming server and proxy, this strategy caches the content of the streaming media partially or completely. The paper also proposes two formulas that calculate the popularity coefficient of a streaming media on server and proxy, and caching replacement policy. As expected, this strategy decreases the server load, reduces the traffic from streaming server to proxy, and improves client start-up latency.  相似文献   
179.
Modeling of D-STATCOM in distribution systems load flow   总被引:1,自引:0,他引:1  
This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems.  相似文献   
180.
学科是大学课程的核心,是左右高校学术命运的指挥棒,决定着我国高校学术研究和学科建设的生存发展。学科制度的运作在一定程度上造成了学科专业之间的隔阂和封闭、行政管理部门的领导使学科合作不能完全按照教育规律和学术精神处置、学科评价制度和学科奖惩制度不科学等是高校学科缺乏交流合作的原因。治理情境下协调学科交流合作的路径是:发展交叉学科、综合性学科和边缘性学科,建设合理科学健全的管理制度,构建学习型院校以及重视学科之间的横向交流合作。  相似文献   
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