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11.
利用中型动三轴仪,对城市固体废弃物(MSW)进行了残余变形试验研究,采用改进的沈珠江模型对MSW的残余变形模型参数进行拟合,在此基础上,讨论了不同破坏标准下的应力水平对模型参数的影响,建议了适合MSW的残余变形模型应力水平指数。MSW属于应变硬化型材料,应力和应变曲线没有明显的峰值,不同破坏标准条件下,相同固结比的MSW具有不同的应力水平,因此建议用固结应力比来代替应力水平,提出了适用于MSW的残余变形修改模型,修改后的模型不必考虑破坏标准对残余变形参数的影响,应用更加方便。  相似文献   
12.
文章以2008年后中国大陆建筑设计执业环境的变化为线索,探究新一代前沿建筑师的建筑实践运作正在发生的变化。作者认为其核心在于"启蒙"的姿态减弱,而日常操作受到更多的重视。文章还通过一些实例具体论述了这种变化对前沿建筑师及其作品特征的影响。  相似文献   
13.
袁菊丽 《应用化工》2011,40(6):990-992
通过研究2年生、3年生西党参的不同月份的产量、多糖含量的动态变化来确定西党参的最佳采收期。结果表明,2年生、3年生党参产量之间存在显著差异(p<0.05)。单因素方差分析表明,多糖含量在相同年限的不同月份之间有极显著差异(p<0.01)。综合考虑产量、多糖含量,确定西党参的最佳采收期为栽培第3年的9~10月。  相似文献   
14.
The concept of Food Safety Margin (FSM) was introduced in microbiological risk analysis as an alternative approach to risk characterization within the informed-risk decision-making process. Its aim was to verify compliance with food safety objectives by assessing the effects of uncertainties. This paper describes the fundamentals and develop a new formulation of safety margins to verify compliance with food safety goals in relation to exposure to non-genotoxic chemical hazards. Both classical and probabilistic metrics were used to compare a given exposure to an estimated daily intake (EDI) with a given safety goal, the acceptable daily intake (ADI). The safety margins of these metrics were assessed in the exposure of peaches to organophosphorus pesticides. The pesticides considered were Azinphos-methyl, Chlorpyrifos, Diazinon, Dimethoate, Methamidophos, Parathion-methyl and Phosmet. The concentrations were obtained from the USDA pesticide database. The study period included the 11 years in which peaches were analysed from 1994 to 2014. The results show the importance of using the effect of uncertainty instead of mean values for risk characterization and that not only safety margins increased during this period but also that uncertainty was reduced. In general, large safety margins were observed in the period studied and few situations were found in which exposure was outside the safety limits.  相似文献   
15.
In this paper we provide further evidence on the suitability of the median of the point VaR forecasts of a set of models as a GFC-robust strategy by using an additional set of new extreme value forecasting models and by extending the sample period for comparison. The median is not affected by extremes, unlike the mean. In periods of contagion, wherein the number and values of extremes are substantially greater, the use of the median would be expected to be even more robust than the mean. These extreme value models include DPOT and Conditional EVT. Such models might be expected to be useful in explaining financial data, especially in the presence of extreme shocks that arise during a GFC. Our empirical results confirm that the median remains GFC-robust even in the presence of these new extreme value models. This is illustrated by using the S&P500 index before, during and after the 2008–2009 GFC. We investigate the performance of a variety of single and combined VaR forecasts in terms of daily capital requirements and violation penalties under the Basel II Accord, as well as other criteria, including several tests for independence of the violations. The strategy based on the median, or more generally, on combined forecasts of single models, is straightforward to incorporate into existing computer software packages that are used by banks and other financial institutions.  相似文献   
16.
With the growing number of reports that daily hemodialysis (DHD) improves clinical outcomes and quality of life, there has been increased interest in the effects of more frequent venipunctures on blood accesses. Since 1996, we have converted 30 patients (27 in‐center, 3 home) from conventional 3/week dialysis to short, daily, 6/week dialysis (sDHD). Twenty‐five patients started for medical indications. End‐stage renal disease (ESRD) causes were diabetes mellitus (in 7), hypertension (6), glomerulonephritis (8), hereditary nephritis (2), and other (7). Mean (±SD) age was 57 ± 16 years. Patients had an average of 3.8 major comorbidities in addition to ESRD. Thirty patients were followed on sDHD for 388 patient‐months: 9 patients died after 4.2 ± 6.7 months, 3 were transplanted at 5.4 ± 2.2 months, and 3 were disenrolled at 9.3 ± 10.5 months. Fifteen patients remain on sDHD at 20.4 ± 14.1 months. Access problems for the 12 months prior to sDHD were compared to those that occurred while the patient was on sDHD. Problems were tracked by access type. There were 40 different accesses in 30 patients with a cumulative 28.07 access‐years pre‐DHD; 24 of these accesses were artificial bridge grafts (ABG) of either polytetrafluoroethylene or bovine material. There were 27 access problems pre‐DHD, or 0.962 problems per access‐year. On sDHD these same 30 patients had 41 accesses for 34.44 access‐years; 23 of these were ABGs. There were 31 access problems or 0.900 problems per access‐year. There were no significant differences in access problems comparing pre‐DHD with on‐sDHD, either in aggregate or when analyzed by access type. After 39 months of observation, there does not appear to be an increase in blood access problems when patients are converted from conventional dialysis to sDHD.  相似文献   
17.
反思我国现阶段旧城改造实施效果产生偏差的深层原因,提出"日常生活"是城市形成的本质,旧城更新应"回归生活世界"的理论观点。借鉴哲学、社会学领域的研究成果,尝试提出基于日常生活视角的旧城更新模式的基本设计原则。以广州市解放中路旧城改造一期工程为例,探索一种自下而上的更符合生活客观发展规律的旧城更新模式。  相似文献   
18.
The daily site report (DSR)—a common tool, which contains a lot of valuable data— is normally used for litigation purposes, i.e. claims and dispute resolution. All these valuable data are rarely used for the management and control of the ongoing project. The purpose of the current research is to develop a tool that uses data taken from a computerized DSR to generate monitoring and control information. We have developed a progress monitoring model, which uses data from a computerized DSR to generate information regarding the actual progress and then transfer it to the scheduling software. The model was developed and implemented in a concept proving prototype using Excel and MS Project. The operation and the usefulness of the prototype are demonstrated with a case study, synthetic, project. The results indicate that the DSR is a useful data collection tool for progress monitoring. The cost of the information generated from these data is low because no additional manual operations are required in order to collect the data.  相似文献   
19.
耿谦 《江苏陶瓷》2004,37(1):15-18
叙述了日用滑石瓷结构中的各种物相比例,主晶相类型、粒径大小及其分布状态、性质,个绍了其具有晶体小、结构细微、光学性质相似,具有同质异构体的独特显微结构,探讨了显微结构与生产工艺、各项性能的相互依赖关系。  相似文献   
20.
随着当今都市报主流化步伐的加速,民生新闻的定位发生了转变。《成都商报》市民版作为都市报民生新闻转向的代表,在报道年轻人新闻、策划年轻人喜爱的活动方面选择年轻化的竞争策略,体现出了都市报在办构建“公共领域”。和“NIE”(Newspaper In Education)工程等前沿领域的创意与举措,本文通过对该报市民版年轻化路线的分析,为都市报民生新闻创新发展提供一定的借鉴。  相似文献   
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