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241.
242.
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   
243.
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   
244.
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   
245.
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   
246.
247.
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   
248.
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   
249.
The purpose of the current study was to investigate a two-stage model in which parent-related stress and hopelessness each served as mediators of the relationship between perceived parental bonding and South Korean adolescent peer victimization. This study also examined whether the mediating relationships differed by the gender of parents and adolescents. A casual chain with three links and four sets of variables were analyzed using structural equation modeling. Data were collected from 800 adolescents attending 10 middle schools in the Busan region of South Korea. Results indicated that both maternal and paternal parental bonding were negatively associated with stress, stress was positively associated with hopelessness, and hopelessness was positively associated with South Korean adolescent peer victimization. Most importantly, the significant negative associations between both maternal and paternal parental bonding and peer victimization were mediated by both stress and hopelessness. Furthermore, gender differences in these relationships existed for both parents and adolescents. Limitations and implications to practice were discussed.  相似文献   
250.
Zusammenfassung Die Entwicklung der mündlichen und schriftlichen Kenntnisse in Deutsch und der Sprache des Herkunftslandes bei Angeh?rigen der ersten und zweiten Einwanderergeneration aus den Gastarbeiter-Anwerbel?ndern, bei Aussiedlern und neuen Zuwanderergruppen wird beschrieben und Erkl?rungsfaktoren für Unterschiede werden mit Hilfe bivariater und multivariater Verfahren untersucht. Die Deutschkenntnisse der ersten Generation steigen zwischen 1984 und 2001 kaum an, wohingegen Aussiedler und Zuwanderer in kurzer Zeit relativ gute Fortschritte aufweisen. Die meisten Befragten sind bilingual. Defizite bei Deutschkenntnissen variieren nach Herkunftsland. Der Zweitspracherwerb erfolgt im Generationenverlauf, d.h. in Deutschland geborene Personen mit Migrationshintergrund haben in der Regel bessere Deutschkenntnisse als die erste Generation. Die Aufenthaltsdauer hat per se keinen Einfluss auf den Spracherwerb, ebenso wie das Geschlecht, w?hrend das Einwanderungsalter und die Schulbildung entscheidende Faktoren sind. Personen mit niedrigem Einwanderungsalter, Personen, die eine weiterführende Schule im Herkunftsland oder eine h?here Schule in Deutschland abgeschlossen haben, haben eine h?here relative Chance, gute mündliche und schriftliche Deutschkenntnisse zu erwerben.   相似文献   
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