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71.
The Australian government initiated a review of higher education in 2008. One of the outcomes of the review was the formation of a national regulator, the Tertiary Education Quality and Standards Agency (TEQSA), with responsibilities to: register all higher education providers, accredit the courses of the non self-accrediting providers, assure quality against externally set standards and reduce risk by monitoring institutional performance on various measures. One of the key changes in Australian higher education quality assurance is the shift from a ‘fitness-for-purpose’ approach to quality assurance to a compliance-driven approach using an externally developed set of standards monitored by the national regulator, which has legislated powers to place sanctions on universities and other providers for non-compliance. This article outlines the new framework introduced by the government and analyses its limitations in assuring and improving quality in core and support areas. It cautions universities against being dominated by TEQSA's compliance agenda. Rather, it encourages the development and maintenance of shared governance principles and strong internal quality improvement processes along with the establishment of an outcomes focus, which will stand the test of external compliance auditing while allowing the institution to pursue its own educational objectives. The article is based on the authors’ experience and reflection on external, improvement-led quality audits in Australia over the past decade compared with the present compliance-oriented audits now required for institutional registration and ongoing accreditation.  相似文献   
72.
In this work, we elaborate on the meaning of metadata quality by surveying efforts and experiences matured in the digital library domain. In particular, an overview of the frameworks developed to characterize such a multi-faceted concept is presented. Moreover, the most common quality-related problems affecting metadata both during the creation and the aggregation phase are discussed together with the approaches, technologies and tools developed to mitigate them. This survey on digital library developments is expected to contribute to the ongoing discussion on data and metadata quality occurring in the emerging yet more general framework of data infrastructures.  相似文献   
73.
原锚喷支护迎头采用的前探梁吊环为传统的不可调式吊环,需用木楔加紧,牢固程度不够可靠。而新研制的吊环上下高度可以通过螺纹调节,使前探梁不随意前后滑动,加强了前探梁支护的整体支护作用。  相似文献   
74.
以我国在美国专利商标局(USPTO)申请的有机精细化工专利为研究对象,采用非专利引文(Non-patent References,NPRs)分析方法,从多个角度对该领域技术创新与科学研究的关系进行探讨。研究表明,我国有机精细化工领域的技术创新对科学研究有着较强的依赖性,且这种依赖有不断增强的趋势;该领域技术创新所需的科学知识主要来自国际一流期刊,美国、中国、日本等是最主要的来源国家,公共科学为我国该领域的发展提供了重要支撑。  相似文献   
75.
Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann–Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis.  相似文献   
76.
滨海地区盐渍土壤对Cd2+的吸附行为   总被引:1,自引:0,他引:1  
为评价Cd2+对上海临港新城滨海地区盐渍土壤的影响,通过研究探讨该土壤对Cd2+的吸附行为及吸附机理.结果表明:Cd2+在上海临港新城滨海盐渍土壤中的吸附行为符合Langmuir等温吸附曲线;pH值对土壤中Cd2+的吸附量有明显影响,当pH值介于4~9时吸附量随pH值的增大而急剧增大,当pH值继续增大时吸附量下降并趋于平缓;电解质氯化钠可显著抑制土壤对Cd2+的吸附,随着氯化钠浓度的增大,吸附量先急剧下降,随后趋于平缓;温度升高有利于土壤对Cd2+的吸附,说明上海临港新城滨海盐渍土壤对外源Cd2+的缓冲能力以及土壤中Cd2+的迁移性和活性具有季节性差异.  相似文献   
77.
从提高环保意识的角度出发,对《有机化学》教学内容提出若干改进意见,并指出《有机化学》教材内容的取舍,应重视环保因素。  相似文献   
78.
采用10m×10m高密度网格设计,在面积为10.24hm2的农田内取土壤样本1024个,测定土壤有机质(SOM)含量,通过"再采样"方法,研究改变取样幅度和取样间距对表征土壤有机质变异特征的变异系数和半方差函数参数的影响,分析获得土壤有机质空间变异特征的尺度效应.研究结果表明,10.24hm2取样区内,土壤有机质空间分布表现为弱变异性,CV≤3.43%,但整体含量偏低,SOM≤1.04%;随着采样幅度增加,土壤有机质变异性不同程度增加,变异相关范围和结构性变异比例也不断增大;当采样间距增大时,土壤有机质变异性呈无规律变化,但变异相关范围显著增大,而结构性变异比例呈下降趋势.  相似文献   
79.
建立了加强后的金属拱型波纹屋盖模型,利用ANSYS有限元分析软件对加强后的波纹拱进行了荷载作用下几何非线性有限元分析,并与原波纹拱进行了变形与应力的比较。计算结果表明,加强后的波纹拱对约束结构位移变形有较好的效果,且提高了结构的承载能力,这一结论为该结构进行抗风、抗雪等设计提供了有益参考。  相似文献   
80.
溶剂萃取法在钨的分离、纯化、富集和回收等方面具有比较明显的优点。而萃取剂[φ(N235)=15%,(φ仲辛醇)=20%,(φ航空煤油)=65%]中有机胺的含量直接关系到钨收率的高低。利用甲基橙与有机胺反应生成黄色络合物,进而用氯仿萃取进行比色测定以监测萃取剂中有机胺的含量,从而保证生产的正常运作。  相似文献   
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