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71.
Soo Chin Pin Fazilah Haron Siamak Sarmady Abdullah Zawawi Talib Ahamad Tajudin Khader 《Safety Science》2011,49(2):286-291
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
72.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g. 相似文献
73.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). Thewire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g. 相似文献
74.
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
75.
MBBR处理猪场废水厌氧消化液的研究 总被引:5,自引:0,他引:5
采用移动床生物膜反应器(MBBR)处理猪场废水厌氧消化液,考察了水力停留时间(HRT),进水COD和NH3-N浓度对反应器处理效果的影响.结果表明,在温度为20~30℃,填料填充比为50%,进水COD和NH3-N浓度分别为1016 mg/L和496 mg/L条件下,当HRT为12.5 h时,COD和NH3-N去除率可分别达到62%和77%,猪场废水厌氧消化液中可生物降解性有机物基本得到去除,当HRT增至23.8 h时,COD和NH3-N去除率分别为64%和86%,出水COD和NH3-N浓度分别为368 mg/L和70 ms/L,均达到了<畜禽养殖业污染物排放标准>(GB18596-2001)的要求. 相似文献
76.
废弃油基钻井液热化学破乳-离心分离实验 总被引:5,自引:1,他引:4
废弃油基钻井液是一种含油量较高的油包水稳定体系,具有回收利用价值。采用热化学破乳-离心分离的方法,考察了破乳剂加量、破乳温度、离心机转速、破乳时间、离心时间和破乳剂浓度对废弃油基钻井液分离的影响。通过实验确定了破乳效果最好的破乳剂为巴斯夫L62,并对热化学破乳-离心分离废弃油基钻井液的影响因素进行了优化实验研究。实验结果表明,在破乳剂加量300 mg/L、离心机转速8 000 r/min、破乳温度80℃、破乳时间3 h、离心时间25 min和破乳剂质量浓度0.25%的条件下,热化学破乳-离心法处理废弃油基钻井液的脱水率达75%、脱油率达72.73%。热化学破乳-离心分离方法回收废弃油基钻井液中的油具有潜在的应用价值。 相似文献
77.
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
78.
Chin Long Chiang 《Environment international》1978,1(6):315-319
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
79.
Khoo Chin Hean 《Environmental monitoring and assessment》1991,19(1-3):127-130
From modest beginnings, Singapore rapidly developed its industrial base which today comprises high technology and high value added industries. Economic growth was accompanied by a comprehensive housing and urban development programme.The formation of the Ministry of the Environment and the Anti-Pollution Unit in the early seventies marked Singapore's commitment to protect the environment in the face of rapid developments.Together with the rapid industrialisation, housing and urban development programme, Singapore also implemented a programme to prevent pollution as well as to control pollution from those sources which cannot be prevented.The success of these programmes is evident today and we have an environment that compares well with that of any nation in the world.Plenary speaker. 相似文献