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101.
三峡工程具有工程量大、工期长的特点,为加快施工进度、缩短工期、节约水泥用量,拟在大坝的部分部位采用碾压混凝土。根据研究,考虑到坝体结构布置、构造要求、RCC施工方法等因素,各坝段采用RCC的部位将有所不同,总的采用原则是在坝体多钢筋的大孔口以下和结构布置简单而较规则的部位应用RCC,但在基岩面上仍铺设1.0-1.5米厚的常态混凝土垫层,按上述原则,各坝段应用RCC混凝土的总量约占大坝总混凝土量的1  相似文献   
102.
To successfully manage today’s complex production systems it is essential to study operators’ perception of the system. The paper presents perceived production complexity assessed at seven manufacturing companies with the CompleXity Index (CXI) method. While other methods have measured product variants, layout, work content, tools and information items, CXI combines them into three areas. These three complexity areas (Station design, Work variance and Disturbance handling) help to create an understanding of the complex system by visualising how they contribute to complexity, and show the need to support the operators’ ability to handle the varying work.  相似文献   
103.
Context: The conventional liquid ophthalmic delivery systems exhibit short pre-corneal residence time and the relative impermeability to the cornea which leads to poor ocular bioavailability.

Objective: The aim of this study was to apply quality by design (QbD) for development of dexamethasone sodium phosphate (DSP) and tobramycin sulfate (TS)-loaded thermoresponsive ophthalmic in situ gel containing Poloxamer 407 and hydroxyl propyl methyl cellulose (HPMC) K4M for prolonging the pre-corneal residence time, ocular bioavability and decreases the frequency of administration of dosage form. The material attributes and the critical quality attributes (CQA) of the in situ gel were identified. Central composite design (CCD) was adopted to optimize the formulation.

Materials and methods: The ophthalmic in situ forming gels were prepared by cold method. Materials attributes were the amount of Poloxamer 407 and HPMC and CQA identified were Gel strength, mucoadhesive index, gelation temperature and % of drug release of both drug.

Results and discussion: Optimized batch (F*) containing 16.75% poloxamer 407 and 0.54% HPMC K4M were exhibited all results in acceptable limits. Compared with the marketed formulation, optimized in situ gel showed delayed Tmax, improved Cmax and AUC in rabbit aqueous humor, suggesting the sustained drug release and better corneal penetration and absorption.

Conclusion: According to the study, it could be concluded that DSP and TS would be successfully formulated as in situ gelling mucoadhesive system for the treatment of steroid responsive eye infections with the properties of sustained drug release, prolonged ocular retention and improved corneal penetration.  相似文献   

104.
Well-founded criticisms of the Consumer Reports (CR; 1995) study of psychotherapy include possible bias of the CR sample; limitations of self-report; and the limitations of cross-sectional, retrospective data. Poorly founded criticisms concern "consumer satisfaction" and the claim that the remarkably good effects of long-term therapy resulted from spontaneous remission, that psychotherapy effects were small, and that nondoctoral providers did as well as doctoral-level providers. Both the experimental method (efficacy) and the observational method with causal modeling (effectiveness) answer complementary questions, and they both do so by eliminating alternative possible causes. Efficacy studies, however, cannot test long-term psychotherapy because long-term manuals cannot be written and patients cannot be randomized into two-year-long placebo controls, so the "empirical validation" of long-term therapy will likely come from effectiveness studies. Such studies of long-term therapy, of qualifications of providers, and of clinical judgment versus case management are urgently needed as practice confronts managed care. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Contends that there are 3 methodological errors and an inconsistency in M. E. P. Seligman's (see record 1996-13324-001) reanalysis of the 1995 Consumer Reports survey of the effectiveness of psychotherapy. These errors are directly relevant to the cost-effectiveness of psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
钟建业  金文 《计算机教育》2011,(11):103-107
新的课程体系促生新的教学理念,新的教学理念引领新的教学模式。本文结合一个具体的高中信息技术课堂案例,分析信息技术课堂中普遍采用的任务驱动教学方法和自主协作学习方法的实施过程,阐述多样化的学习方式对培养高中学生的问题分析能力、自主探究能力、合作学习能力以及提升学生的信息素养所起的促进作用。  相似文献   
107.
针对大学本科高级语言程序设计教学中对学生学习兴趣的培养不够重视的实际状况,文章在分析学习兴趣对教学重要性的基础上,就如何培养和提高学生的学习兴趣进行了深入的研究;结合笔者在计算机本科教学改革中所作的尝试,着重从融洽师生感情、认识课程重要性、精心选择例题、多模式教学、丰富学习交流互动渠道和改进实验体系6个方面给出了合理有效的方法,有效地培养和提高学生的学习兴趣,在很大程度上提高了整体教学效果。  相似文献   
108.
In recent years the use of new technical equipment and the Internet by middle-aged people has increased. This paper presents middle-aged people’s (45 years old or older) usage of new technical equipment and analyses how their (2704 persons) symptoms are associated with the equipment. Over 70% of Finland’s middle-aged population use mobile phones daily and less than 30% use desktop computers at leisure. For example, over 80% of middle-aged people had sometimes or often experienced pain, numbness or aches in the neck and about 70% had aches in the hip and lower back. The use of new technical equipment among the group of people who are outside working life was smaller than the people’s usage in general. In the future, when new technical equipment is developed, it is important to take into account, that people (outside working life) do not use, e.g., the Internet as much as people in general. The working environment will be much more ergonomic also at home and the Internet services will be easy to use for almost everyone, even those who have little experience or knowledge of computers and the Internet.  相似文献   
109.
110.
An important step towards the successful integration of information and communication technology (ICT) in schools is to facilitate their capacity to develop a school‐based ICT policy resulting in an ICT policy plan. Such a plan can be defined as a school document containing strategic and operational elements concerning the integration of ICT in education. To write such a plan in an efficient way is challenging for schools. Therefore, an online tool [Planning for ICT in Schools (pICTos)] has been developed to guide schools in this process. A multiple case study research project was conducted with three Flemish primary schools to explore the process of developing a school‐based ICT policy plan and the supportive role of pICTos within this process. Data from multiple sources (i.e. interviews with school leaders and ICT coordinators, school policy documents analysis and a teacher questionnaire) were collected and analysed. The results indicate that schools shape their ICT policy based on specific school data collected and presented by the pICTos environment. School teams learned about the actual and future place of ICT in teaching and learning. Consequently, different policy decisions were made according to each school's vision on ‘good’ education and ICT integration.  相似文献   
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