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101.
Overcrowding that happens in places like concerts, stadiums or pilgrimage locations might sometimes cause injury or loss of life. Maintaining the safety of crowd in these places is therefore very important. In addition, increasing the performance of the buildings and structures has always been an important concern. Most of the previous work focused on using new devices and methods for monitoring and management of the crowd but they rarely focus on a comprehensive and structured approach with the purpose of increasing efficiency and safety. In this paper, we explore a Russian “Theory of Inventive Problem Solving”, TRIZ, to see whether its principles can help us to solve or improve overcrowding issues. More specifically we find the contradictions that arise in the context of crowd management and we observe which of the categorical solutions suggested by TRIZ might possibly be useful for our problem. Increasing the crowd capacity in a relatively small area, which leads to overcrowding, is one of the common contradictions in crowd management. TRIZ has been suggested as a good method for solving problems which involve contradiction and thus, chosen for this purpose.  相似文献   
102.
Seasonality is often the major exogenous effect that must be compensated for or removed to discern trends in water quality. Our objective was to provide a methodological example of trend analysis using water quality data with seasonality. Selected water quality constituents from 1979 to 2004 at three monitoring stations in southern Florida were evaluated for seasonality. The seasonal patterns of flow-weighted and log-transformed concentrations were identified by applying side-by-side boxplots and the Wilcoxon signed-rank test (p < 0.05). Seasonal and annual trends were determined by trend analysis (Seasonal Kendall or Tobit procedure) using the U.S. Geological Survey (USGS) Estimate TREND (ESTREND) program. Major water quality indicators (specific conductivity, turbidity, color, and chloride), except for turbidity at Station C24S49, exhibited significant seasonal patterns. Almost all nutrient species (NO(2)-N, NH(4)-N, total Kjeldahl N, PO(4)-P, and total P) had an identical seasonal pattern of concentrations significantly greater in the wet than in the dry season. Some water quality constituents were observed to exhibit significant annual or seasonal trends. In some cases, the overall annual trend was insignificant while opposing trends were present in different seasons. By evaluating seasonal trends separately from all data, constituents can be assessed providing a more accurate interpretation of water quality trends.  相似文献   
103.
In implementing effective remedial treatments at hazardous intersections, it often is necessary to identify the geometric and traffic factors that lead to accident occurrence. However, one particular problem frequently encountered in accident studies is how to distinguish virtually safe intersections with little likelihood of accident occurrence from those that have happened to have no accident due to the random process. To deal with this problem, the "excess" records of zero accident, the zero-inflated negative binomial was used to assign the probability to the accident outcome. Accident data at 104 signalized tee intersections in Singapore over a period of 9 years were employed for model development. The model indicates that uncontrolled left-turn slip road, permissive right-turn phase, existence of a horizontal curve, short sight distances, large number of signal phases, total approach volume, and left-turn volume may increase accident occurrence. On the other hand, right-turn channelization, acceleration section on the left-turn lane, median railings, and more than 5% approach gradient may reduce accident occurrence. Moreover, there is a trend of reducing accidents over the years.  相似文献   
104.
酞菁绿废渣中含有较多的铝化合物和少量的铜化合物及染料残渣,本文采用H2SO4除Ca2^ 、Al灰除Cu^2 或NaOH浸取Al^3 的反应条件和工艺过程,制得Al(OH)3产品,并进一步合成性能优良的聚合铝产品。废渣经处理后不仅回收了利用价值较高的铝,取得了一定的经济效益,同时不产生二次污染,也取得了明显的环境效益。  相似文献   
105.
广东省香蕉寒害风险分析   总被引:10,自引:2,他引:8  
根据各地寒害及香蕉的产量资料,从寒害对香蕉产量的影响出发,对广东省各地香蕉的灾损率、易灾性进行了分析,以寒害风险指数作为区划指标,对广东省的香蕉寒害风险进行了区划,并作了分区评述。  相似文献   
106.
废水中有机污染指标监测方法的选择   总被引:16,自引:0,他引:16  
综合考察了废水中各种有机污染物综合指标的测试对象、干扰、准确度、精确度及其分析测试技术等各种因素 ,对实现其自动化连续测量的影响。针对某些监测技术产生的严重二次污染问题 ,提出了绿色 (清洁 )监测技术的概念。文章认为在重点废水污染源安装在线监测系统实行总量控制的过程中 ,应避免使用造成严重二次污染的 CODCr在线监测仪 ,而应当采用臭氧氧化法在线监测仪 ,或其他综合指标 ,如 TOC  相似文献   
107.
通过对基于事例推理 (CBR)技术及注塑模设计过程的分析 ,得出将CBR思想应用到注塑模结构设计中的可行性和必要性 ,提出了一个基于事例的注塑模结构智能设计系统的总体结构 ,并分析了关键技术的实现方法  相似文献   
108.
稀土元素广泛用于岩浆起源、岩浆演化和岩石学领域,用于矿床成因研究和指导找矿只是近几年来的事。笔者通过对河南蒲塘、毛堂金矿不同类型矿石、岩石稀土元素研究,认为在氧化和热液作用下轻稀土元素淋失,重稀土元素相对富集,ΣLREE/ΣHREE比值和ΣREE降低,热液和表生氧化作用对稀土元素的影响是通过斜长石的形成与分解实现的。研究表明,矿化强度与δEu和ΣLRE/ΣHRE有一定的相关关系,这一关系可作为矿床评价的标志之一。  相似文献   
109.
The concept of the life table originated in longevity studies of man, where it was always presented as a subject peculiar to public health, demography, and actuarial science. As a result, its development has not received sufficient attention in the field of statistics. Actually, the problems of mortality studies are similar to those of reliability theory and life testing, and they may be described in terms familiar to the statistically oriented mind. From a statistical point of view, human life is a random experiment and its outcome, survival or death, ss subject to chance. The life table systematically records the outcomes of many such experiments for a large number of individuals over a period of time. Thus, the quantities in the table are random variables subject to established statistical analysis. The purpose of this presentation is to discuss the life table from a statistical viewpoint.  相似文献   
110.
城市生活垃圾在热解处理中的产气特性研究   总被引:7,自引:0,他引:7  
通过对沈阳市皇姑区内的3个垃圾排放点进行实地采样并分类称量,得出其组分含量,得到了生活垃圾的主要物料组份.在此基础上在外加热固定床式热解试验台上,用热解实验的方法对8种城市生活垃圾中的主要物料中的典型成分进行热解试验.通过数据分析总结出不同工况下产气特性和热解气体的组分含量、热值,并建立热解气体析出模型进行产气量预测.  相似文献   
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