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排序方式: 共有129条查询结果,搜索用时 15 毫秒
71.
Modeling and multi-objective optimization of a gasoline engine using neural networks and evolutionary algorithms 总被引:1,自引:0,他引:1
José D.MARTNEZ-MORALES Elvia R.PALACIOS-HERNNDEZ Gerardo A.VELZQUEZ-CARRILLO 《浙江大学学报(A卷英文版)》2013,14(9):657-670
In this paper, a multi-objective particle swarm optimization (MOPSO) algorithm and a nondominated sorting genetic algorithm II (NSGA-II) are used to optimize the operating parameters of a 1.6 L, spark ignition (SI) gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks (ANNs) were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms: NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively. 相似文献
72.
Monica Ramirez 《TechTrends》1996,41(2):34-36
73.
74.
April Richardson‐Hatcher Matthew Hazzard German Ramirez‐Yanez 《Anatomical sciences education》2014,7(6):469-478
Visualization of the complex courses of the cranial nerves by students in the health‐related professions is challenging through either diagrams in books or plastic models in the gross laboratory. Furthermore, dissection of the cranial nerves in the gross laboratory is an extremely meticulous task. Teaching and learning the cranial nerve pathways is difficult using two‐dimensional (2D) illustrations alone. Three‐dimensional (3D) models aid the teacher in describing intricate and complex anatomical structures and help students visualize them. The study of the cranial nerves can be supplemented with 3D, which permits the students to fully visualize their distribution within the craniofacial complex. This article describes the construction and usage of a virtual anatomy platform in Second Life?, which contains 3D models of the cranial nerves III, V, VII, and IX. The Cranial Nerve Skywalk features select cranial nerves and the associated autonomic pathways in an immersive online environment. This teaching supplement was introduced to groups of pre‐healthcare professional students in gross anatomy courses at both institutions and student feedback is included. Anat Sci Educ 7: 469–478. © 2014 American Association of Anatomists. 相似文献
75.
Gerardo Moreno 《Education 3-13》2013,41(4):363-371
When a student demonstrates a challenging or problematic behaviour in the classroom, the climate and the instructional experience can change dramatically for both the students and the classroom teacher. Before resorting to sanctions and punitive consequences, there is a series of steps a classroom teacher can conduct to reduce and replace the challenging behaviour with desired and positive behaviours. The Functional Behavioural Assessment (FBA) is a systematic data collection process used to ascertain information about a student demonstrating a challenging behaviour(s). Typically reserved for students receiving special education services, the FBA can assist students in the general education curriculum as well. More importantly, the FBA process can be of great use in helping the classroom teacher better understand the challenging behaviour, the triggers for the behaviour and the reinforcing consequences of the behaviour. This paper will review the fundamentals of the FBA process, advantages of the process, and practical steps the classroom teacher can use to conduct an FBA. 相似文献
76.
Charles Grant Joyce Langenegger Arnold Ramirez Granville Sydnor 《Community College Journal of Research & Practice》2013,37(11):915-917
Strong partnerships and external funding allowed San Jacinto College North to engage a declining community to transform into one valuing education. A community center, training classes, and student support programs contributed to this effort. The results included doubling Hispanic college enrollment, skyrocketing high school graduation rates, and increasing earning power. 相似文献
77.
Artemio Ramirez Jr. 《Communication Studies》2013,64(1):53-70
This study applies the critical paradigm of “rhetorical enterprise” to the case of nineteenth‐century British reform efforts, particularly the organization and the “gospel” of the Birmingham Political Union, and concludes that cases of rhetorical enterprise challenge critics to account for the enterprising consistency of tactics and creed regardless of the relatively inconsistent factors of men andevents. 相似文献
78.
Lee Diane Sookyoung Ramirez Garcia Jose Manuel Overton Larissa Gordon Biddle Kimberly A. Lacey Rodney O. Gorter Josiah Heller de Leon Brian 《The Urban Review》2022,54(4):624-648
The Urban Review - The purpose of this study was to identify the internal and external factors that support the academic and career resourcefulness of adolescents from underserved backgrounds. This... 相似文献
79.
Alfredo Cordova Jorge Monserrat Gerardo Villa Eduardo Reyes Melchor Alvarez-Mon Soto 《Journal of sports sciences》2013,31(6):565-573
Abstract The aims of this study were to examine the changes in plasma concentrations of inflammatory cytokines induced by training and competition in professional cyclists. We report the serum concentrations of interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), tumour necrosis factor receptors I and II (TNFR-I and -II) in a prospective, randomized, double-blind trial involving the administration of AM3 (Inmunoferon®), an oral booster immunomodulator, or placebo to 16 professional cyclists (n=8 in each group) for 65 consecutive days. Serum was collected just before treatment began (baseline), at the end of pre-competition training, before the mountain stage of the competition (60 days), 4 h after finishing this stage (62 days), and 18 h after the fifth and last day of competition (65 days). To determine the normal levels of cytokines and soluble TNF receptors, individual samples from 14 moderately trained healthy controls were studied. After 60 days of training, the serum concentrations of IL-6 did not differ significantly from those at the beginning of the study for either group of cyclists (placebo and AM3). A significant rise was seen in IL-6 concentrations in both the AM3 and placebo groups at 62 days, 4 h after finishing the mountain stage. The increase was significantly greater in the placebo group than in the AM3 group. At 65 days of treatment, 18 h after the fifth and last day of competition, IL-6 concentrations were similar to those recorded at the end of the training, but were significantly higher in the placebo group than in the AM3 group. At the end of training, serum TNFR-I concentrations in both groups of cyclists were significantly lower than at baseline. The concentrations of serum TNFR-I and -II both 4 h after finishing the mountain stage and 18 h after the fifth and last day of competition were significantly higher than those recorded after training in both groups. Professional cycling competition is associated with increases in serum IL-6 and TNFR-I and -II concentrations. Inmunoferon treatment reduced significantly the concentrations of IL-6 but not those of TNFR-I and -II. 相似文献
80.
Johnny Padulo Davide Filingeri Karim Chamari Gian Mario Migliaccio Giuseppe Calcagno Gerardo Bosco 《Journal of sports sciences》2013,31(12):1120-1126
AbstractThe aim of this study was to investigate the effects of a single bout of whole-body vibration (WBV) on running gait. The running kinematic of sixteen male marathon runners was assessed on a treadmill at iso-efficiency speed after 10 min of WBV and SHAM (i.e. no WBV) conditions. A high-speed camera (210 Hz) was used for the video analysis and heart rate (HR) was also monitored. The following parameters were investigated: step length (SL), flight time (FT), step frequency (SF), contact time (CT), HR and the internal work (WINT). Full-within one-way analysis of variance (ANOVA) of the randomised crossover design indicated that when compared to SHAM conditions, WBV decreased the SL and the FT by ~4% (P < 0.0001) and ~7.2% (P < 0.001), respectively, and increased the SF ~4% (P < 0.0001) while the CT was not changed. This effect occurred during the first minute of running: the SL decreased ~3.5% (P < 0.001) and SF increased ~3.3% (P < 0.001). During the second minute the SL decreased ~1.2% (P = 0.017) and the SF increased ~1.1% (P = 0.02). From the third minute onwards, there was a return to the pre-vibration condition. The WINT was increased by ~4% (P < 0.0001) during the WBV condition. Ten minutes of WBV produced a significant alteration of the running kinematics during the first minutes post exposure. These results provide insights on the effects of WBV on the central components controlling muscle function. 相似文献