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71.
论21世纪图书馆的发展模式与功能 总被引:3,自引:0,他引:3
本文分析了影响决定图书馆发展模式的四个重要因素。即技术、资金、文化心态和制度变迁。认为模式的不同导致图书馆功能在不同时代的差异,并提出了21世纪图书馆的四种发展模式,阐述了它们的主要功能。 相似文献
72.
致力于中国农民素质教育是电大系统实施网络教育必须担负的历史使命,基层电大接轨农村、服务农民是开放教育可持续发展的必然趋势。当今农村地区发展的不平衡现状和农民个体活动呈现的独立性、选择性、多变性等形态,决定了各地基层电大在向农村和农民实施开放教育的过程中,必须于教育观念、教育技术以及教育中远期目标上紧紧把持和谐的理念。 相似文献
73.
Audio steganalysis based on "negative resonance phenomenon" caused by steganographic tools 总被引:1,自引:0,他引:1
RU Xue-min ZHUANG Yue-ting WU Fei 《浙江大学学报(A卷英文版)》2006,7(4):577-583
INTRODUCTION With the rapid progress in the Internet and ex- panded area of multimedia technology, steganogra- phy and steganalysis as subfields of information se- curity have developed rapidly and drawn more and more attention. Steganography is the art of hiding and transmitting data through apparently innocuous car- riers in an effort to conceal the existence of the secret data (Peticolas et al., 1999). While steganalysis, the countermeasure to steganography, is an art that de- tects ev… 相似文献
74.
GUO Hui WANG Yun-peng WANG Zhi-guang ZHOU Jing-li 《浙江大学学报(A卷英文版)》2006,7(6):1001-1007
INTRODUCTION Because of the critical role that computing sys-tems and networks play in today’s business envi-ronment, it is not surprising that business success often goes to the company with the best information and the most efficient process for delivering that in-formation. As the principal tool for business col-laboration, corporate LANs are a vital resource in enabling today’s enterprises to adopt competitive strategies. The number of users wanting to share and access data across… 相似文献
75.
Imbalanced free radicals and antioxidant defense systems in schizophrenia: A comparative study 总被引:2,自引:0,他引:2
Objective: To examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms. Methods: Forty-six Chinese patients met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders-iV) criteria for schizophrenia and fifty age- and sex-matched healthy controls were enrolled in the present study. Baseline psychiatric symptom severity was assessed with brief psychiatric rating scale, positive and negative syndrome scale on the blood draw day. Fresh blood samples were collected to measure levels of nitric oxide and lipid peroxide in plasma as well as activities of superoxide dismutase, catalase and glutathione peroxidase in red blood cells by spectrophotometric assays simultaneously. Results Comparison of the biochemical parameters indicated that the level of nitric oxide and lipid peroxide increased in patient group, which represented a positive correlation with positive scale scores; while the activities of three critical enzymes decreased and showed a negative linear correlation. Conclusion: This study showed that there are dysregulation of free radical metabolism and poor activities of the antioxidant defense systems in schizophrenic patients. Excess free radicals formation may play a critical role in the etiology of schizophrenia. Using antioxidants might be an effective therapeutic approach to partially alleviate or prevent the symptoms of schizophrenia. 相似文献
76.
毕业要求达成度是基于成果导向教育模式(Outcomes--based Education,OBE)的核心概念,对其评价的合理性直接影响到OBE教育模式的实施效果。传统的相关评价中存在教育过程性因素考查不充分、指标不独立引起的信息损失过多、评价方法使用受限、评价结果不准确等问题,而基于网络层次分析法(ANP)的毕业要求达成度评价可在一定程度上解决这些问题。该评价方法不仅有效融入了教育全过程因素,而且充分考虑了各指标间的关联性,能够反映出全部指标的相对重要度,减少了信息损失,更符合OBE中毕业要求达成度的评价要求。 相似文献
77.
毕业设计是高职教育的一个重要的实践性教学环节,但目前商务英语专业毕业设计中还存在许多问题,与商务英语专业人才培养目标有一定的偏差。本文针对上述问题,结合我校商务英语专业毕业设计实践,提出构建基于成果为本的毕业设计模式,以保证毕业设计的质量,并期望能为高职毕业设计改革提供思路。 相似文献
78.
Qi WANG Xiaoxia SHEN Tian QIU Wei WU Lin LI Zhi'an WANG Huixia SHOU 《Journal of Zhejiang University. Science. B》2021,22(2):99
Nucleic acids in plant tissue lysates can be captured quickly by a cellulose filter paper and prepared for amplification after a quick purification.In this study,a published filter paper strip method was modified by sticking the filter paper on a polyvinyl chloride resin(PVC)sheet.This modified method is named EZ-D,for EASY DNA extraction.Compared with the original cetyl trimethylammonium bromide(CTAB)method,DNA extracted by EZ-D is more efficient in polymerase chain reaction(PCR)amplification due to the more stable performance of the EZ-D stick.The EZ-D method is also faster,easier,and cheaper.PCR analyses showed that DNA extracted from several types of plant tissues by EZ-D was appropriate for specific identification of biological samples.A regular PCR reaction can detect the EZ-D-extracted DNA template at concentration as low as 0.1 ng/μL.Evaluation of the EZ-D showed that DNA extracts could be successfully amplified by PCR reaction for DNA fragments up to 3000 bp in length and up to 80%in GC content.EZ-D was successfully used for DNA extraction from a variety of plant species and plant tissues.Moreover,when EZ-D was combined with the loop-mediated isothermal amplification(LAMP)method,DNA identification of biological samples could be achieved without the need for specialized equipment.As an optimized DNA purification method,EZ-D shows great advantages in application and can be used widely in laboratories where equipment is limited and rapid results are required. 相似文献
79.
基于地震反射波法超前预测系统的原理及主要技术手段,以栋梁坡隧道工程为实例,针对隧道复杂的地质条件,施工过程中将超前地质预报和地质素描调查相结合,先对隧道全段范围内地形、地层岩性等进行全面核查,然后结合核查结果运用地震反射波法预报掌子面前方的节理裂隙发育情况,围岩完整性等地质信息.开挖后验证情况与预测结果基本一致,为后续... 相似文献
80.
ABSTRACT The Colorado Reading to Ensure Academic Development Act requires grade-level attainment in literacy in English for students in grades K-3. Its practical outcome, however, has been to pressure schools with bilingual programs to shift their instructional language allocations towards more English in the early grades. Proposed rule revisions debated by the state Board of Education sought to facilitate testing in students’ language of instruction for those in bilingual programs. Analysis of written and verbal opposition to the proposed rule revisions demonstrates the persistence of insidious ethnoculturalist discourses opposing bilingual education as well as the cooptation of liberal multiculturalist discourses that, while framing bilingualism as an asset, argue that it is underdeveloped in bilingual programs that do not include English instruction from the outset. Given that bilingual instruction has demonstrated time and again that it benefits students acquiring English in schools, such new discursive turns pose a threat that must be recognized to fend off further legislative and regulatory attempts against bilingual education. 相似文献