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101.
将BP神经网络结合遗传算法用于铜板带冷轧轧制力的预测,并与以Bland-Ford公式为基础的冷轧力预报及引入遗传算法前的网络预报结果进行对比分析,实验结果表明本文的方法具有较高的计算精度. 相似文献
102.
非自愿性移民从农村动迁到城市,户籍身份由村民变为市民,但这并不意味着村民就成为真正的市民。从村民到市民,要经历职业、社会规范、精神文化、价值观等一系列的嬗变。这一嬗变过程将是一个艰巨而又漫长的过程。只有在这些方面嬗变实现之后,村民才是真正的市民。 相似文献
103.
针对学前教育学科信息用户需求特点,以陕西学前师范学院图书馆为例,提出学前教育学科团队协同服务模式。该模式整合了学前教育学科资源,促进了馆藏特色的发展;引入用户参与构建学科资源,能实现学前教育学科资源的优化,扩大学前教育学科服务的范围和内容。目前,该模式还亟需推进嵌入式服务的进程,并构建一站式学前教育学科服务平台。 相似文献
104.
数学问题的(P,M)分类方法,是指从问题与解题思想方法的统一下来对数学问题分类,分类的结果可以使每一类都有适合于其特征的基本解题思想方法,于是使解题者能够根据问题的特征较为容易地判断所需要的思想方法,使问题得到解决。然而,这种分类不仅需要解题者随着数学知识的日益丰富来完成,更需要一定的特例来理解。 相似文献
105.
屈琦 《渭南师范学院学报》2014,(5):13-16
权利与权力之间存在难以消弭的张力。在权利缺失情况下,存在着权力异化并制造犯罪的倾向:行政权的肆意扩张使得公民成为潜在的“罪犯”;侦查权的滥用则使公民向“自证其罪”转化;司法权的专断则使得公民“自证其罪”得以“司法确认”而成为“罪犯”。权利对权力的制衡是避免权力造罪的根本途径。 相似文献
106.
Jun-xian CAO Lu FU Qian-ping GAO Rong-sheng XIE Fan QU 《Journal of Zhejiang University. Science. B》2014,15(6):515-521
Objective
To investigate stretch-induced electrophysiological changes in chronically infarcted hearts and the effect of streptomycin (SM) on these changes in vivo.Methods
Sixty Wistar rats were divided randomly into four groups: a control group (n=15), an SM group (n=15), a myocardial infarction (MI) group (n=15), and an MI+SM group (n=15). Chronic MI was obtained by ligating the left anterior descending branch (LAD) of rat hearts for eight weeks. The in vivo blockade of stretch-activated ion channels (SACs) was achieved by intramuscular injection of SM (180 mg/(kg·d)) for seven days after operation. The hearts were stretched for 5 s by occlusion of the aortic arch. Suction electrodes were placed on the anterior wall of left ventricle to record the monophasic action potential (MAP). The effect of stretching was examined by assessing the 90% monophasic action potential duration (MAPD90), premature ventricular beats (PVBs), and ventricular tachycardia (VT).Results
The MAPD90 decreased during stretching in both the control (from (50.27±5.61) ms to (46.27±4.51) ms, P<0.05) and MI groups (from (65.47±6.38) ms to (57.47±5.76 ms), P<0.01). SM inhibited the decrease in MAPD90 during inflation ((46.27±4.51) ms vs. (49.53±3.52) ms, P<0.05 in normal hearts; (57.47±5.76) ms vs. (61.87±5.33) ms, P<0.05 in MI hearts). The occurrence of PVBs and VT in the MI group increased compared with that in the control group (PVB: 7.93±1.66 vs. 1.80±0.86, P<0.01; VT: 7 vs. 1, P<0.05). SM decreased the occurrence of PVBs in both normal and MI hearts (0.93±0.59 vs. 1.80±0.86 in normal hearts, P<0.05; 5.40±1.18 vs. 7.93±1.66 in MI hearts, P<0.01).Conclusions
Stretch-induced MAPD90 changes and arrhythmias were observed in chronically infarcted myocardium. The use of SM in vivo decreased the incidence of PVBs but not of VT. This suggests that SACs may be involved in mechanoelectric feedback (MEF), but that there might be other mechanisms involved in causing VT in chronic MI. 相似文献107.
辅助生殖技术学龄前单双胎子代的认知发展存在差异么?(英文)简 总被引:1,自引:0,他引:1
Lan-feng XING Yu-li QIAN Lu-ting CHEN Fan-hong ZHANG Xin-fen XU Fan QU Yi-min ZHU 《Journal of Zhejiang University. Science. B》2014,15(1):51-57
Objective: To explore whether there exist differences in cognitive development between singletons and twins born after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Methods: A total of 566 children were recruited for the study, including 388 children (singletons, n=175; twins, n=213) born after IVF and 178 children (singletons, n=87; twins, n=91 ) born after ICSI. The cognitive development was assessed using the Chinese-Wechsler Intelligence Scale for Children (C-WISC). Results: For all pre-term offspring, all the intelligence quotient (IQ) items between singletons and twins showed no significant differences no matter if they were born after IVF or ICSI. There was a significant difference in the cognitive development of IVF-conceived full-term singletons and twins. The twins born after IVF obtained significantly lower scores than the singletons in verbal IQ (containing information, picture & vocabulary, arithmetic, picture completion, comprehension, and language), performance IQ (containing maze, visual analysis, object assembly, and performance), and full scale IQ (P〈0.05). The cognitive development of full-term sin- gletons and twins born after ICSI did not show any significant differences. There was no significant difference between the parents of the singletons and twins in their characteristics where data were collected, including the age of the mothers, the current employment status, the educational backgrounds, and areas of residence. There were also no consistent differences in the duration of pregnancy, sex composition of the children, age, and height between sin- gletons and twins at the time of our study although there existed significant differences between the two groups in the sex composition of the full-term children born after ICSI (P〈0.05). Conclusions: Compared to the full-term singletons born after IVF, the full-term twins have lower cognitive development. The cognitive development of full-term singletons and twins born after ICSI did not show any significant differences. For all pre-term offspring, singletons and twins born after IVF or ICSI, the results of the cognitive development showed no significant differences. 相似文献
108.
军校研讨式教学方法改革评述 总被引:1,自引:0,他引:1
从研讨式教学的内涵、研讨题目的设定、研讨的时机和学时分配以及研讨式教学中教师和学生的角色定位等四个方面,对近年来军校开展研讨式教学研究与实践的概况做了评述;对当前研讨式教学面临的学生课余时间精力不足、参与讨论积极性不高和课业成绩评价难等问题进行了初步探讨。 相似文献
109.
针对工程训练实践教学中存在的问题,分析了工科类学生理论学习与工程训练中心自身建设特点,结果表明:工科学生在高年级时需要进一步掌握较深层次的实践能力.为此,应开设一门新型实践教学课程,为高年级学生搭建基本设计和自主设计的实验平台.对机、电、气综合创新教学实验平台进行了研究,提出了实验平台的基本内容、预期效果及创新点,对高校实践教学具有一定的借鉴作用. 相似文献
110.