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排序方式: 共有461条查询结果,搜索用时 31 毫秒
51.
Learning From Noisy Examples 总被引:24,自引:8,他引:16
Machine Learning - The basic question addressed in this paper is: how can a learning algorithm cope with incorrect training examples? Specifically, how can algorithms that produce an... 相似文献
52.
Zax Melvin; Cowen Emory L.; Rappaport Julian; Beach David R.; Laird James D. 《Canadian Metallurgical Quarterly》1968,32(4):369
2 consecutive groups of 1st-grade children classified for their potential for being emotionally disturbed were reexamined upon reaching 7th grade. Children manifesting high potential for being disturbed (labeled Red Tag) were compared, on school record and special test measures, with peers evidencing low potential for disturbance (labeled Non-Red Tag). These measures reflected achievement, classroom behavior, peer perceptions, attendance, and school nurse referral. Both groups of Red Tag children scored significantly more negatively than Non-Red Tag children on 10 of 47 measures in one case and on 13 of 42 in the other. These findings support the hypothesis that early disturbance in children is not ephemeral and is a portent for later difficulty. Implications of such results for programs in early identification and prevention were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Investigated the relationship of child abuse and neglect to academic achievement and discipline problems in a school-age population. A representative community sample of 420 maltreated children in kindergarten through Grade 12 were matched with 420 nonmaltreated children in the same community. Using social service and school records as the sources of data, the authors found maltreated children performed significantly below their nonmaltreated peers in standardized tests and grades and were more likely to repeat a grade. Maltreated children also had significantly more discipline referrals and suspensions. Of the maltreated children, neglected children showed the poorest outcomes on academic performance, and physically abused children showed the most discipline problems. Variations in maltreatment effects by grade level, public assistance status, and gender are also described. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
烽火通信科技股份有限公司 《邮电设计技术》2009,(10):31-33
从独立组网模式和混合组网模式2个方面阐述了烽火通信分组传送网(PTN)解决方案;介绍了中国移动2008年组织的三轮PTN测试;最后介绍了烽火通信阻N工程的商用情况。 相似文献
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57.
Michael Bynum Anya Castillo Jean-Paul Watson Carl D. Laird 《American Institute of Chemical Engineers》2019,65(7):e16508
While peak shaving is commonly used to reduce power costs, chemical process facilities that can reduce power consumption on demand during emergencies (e.g., extreme weather events) bring additional value through improved resilience. For process facilities to effectively negotiate demand response (DR) contracts and make investment decisions regarding flexibility, they need to quantify their additional value to the grid. We present a grid-centric mixed-integer stochastic programming framework to determine the value of DR for improving grid resilience in place of capital investments that can be cost prohibitive for system operators. We formulate problems using both a linear approximation and a nonlinear alternating current power flow model. Our numerical results with both models demonstrate that DR can be used to reduce the capital investment necessary for resilience, increasing the value that chemical process facilities bring through DR. However, the linearized model often underestimates the amount of DR needed in our case studies. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. AIChE J, 65: e16508, 2019 相似文献
58.
是德科技 《国外电子测量技术》2015,34(7):90-90
59.
是德科技 《国外电子测量技术》2015,34(12):68-68
主要优点:
1)新 UXM 软件版本支持 4×4 MIMO 数据吞吐量测试
2)添加 TM9 和空间信道模型,可以实现真实的终端性能验证 相似文献
60.
Compatibility stresses are calculated for twist boundaries about [1¯49] and a “random” high angle boundary between a [1¯49] grain and a [100] grain, assuming piecewise homogeneous elastic fields and copper as model material. The “in-plane” compatibility stresses produced by uniaxial tension perpendicular to the boundary are a strong function of the crystallography of the grains and their misorientation. The effects of small plastic strains via crystallographic slip are also studied for three particular misorientations ([1¯49] 90° and 180° twist boundaries and the “random” misorientation) and the type and amount of slip close to the boundary predicted by minimizing the elastic energy and using experimental measurements of the axial component of the plastic strain. The predictions agree quite well with experimental observations of slip traces close to the boundaries of copper bicrystals with those misorientations tested under high cycle fatigue conditions. 相似文献