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1.
为分析影响常减压蒸馏装置平稳运行的设备失效模式及故障部件,基于1 151条设备故障数据,采用Bayesian网络分析方法,分别对离心泵、压缩机、电动机构建基于Bayesian网络的设备故障概率分析模型,分析故障部件、失效模式、故障后果之间的定量概率关系。研究结果表明:离心泵、压缩机、电动机停运的关键致因部件分别为轴承箱密封故障、活塞环故障、轴承故障,同时得到导致设备停运的故障部件敏感度排序。研究结果有助于提高设备故障风险防范及检维修工作效率,同时可为备件优化方案提供思路。  相似文献   

2.
为了实现高炉出铁场除尘风力自动跟踪烟尘浓度控制,对尘源点烟尘浓度模型进行分析,并由此提出一种针对多测点反馈的新型控制策略.该策略构建了多测点数据的综合评价体系,从控制的角度建立烟尘浓度当前值、当前变化率以及预测变化率3项评价指标,运用功效系数法加入主观评判因素,用熵值法对各测点数据进行综合评价,选择合适的数据进行反馈.利用Matlab/Simulink软件对模糊控制策略下的除尘系统进行了对比仿真试验.结果表明,该控制策略能够实现除尘风力自动跟踪烟尘浓度控制,与传统的控制方式相比,节能效果显著,且综合评价反馈比常规反馈算法节能效果更优.  相似文献   

3.
An approach, based purely on steady-state analyses, for synthesizing effective control structures for reactive distillation (RD) columns is presented. The main idea is to analyze the steady-state relationships between the manipulated (input) variables and the potential controlled (output) variables to identify input–output (IO) pairings that are sensitive and avoid steady-state multiplicities providing a large range of nearly linear operating region around the base case design. Traditional SISO control loops are then implemented using these IO pairings to obtain control structures that maintain the column near the design product purity and conversion for the anticipated primary disturbances. The Niederlinski Index is used to eliminate dynamically unstable pairings in control structures with multiple loops. The approach is demonstrated on an example MTBE RD column. The impact of steady-state multiplicities on control structure design is highlighted.  相似文献   

4.
针对传统GM(1,1)模型建模方法存在偏差,当发展系数的绝对值较大时,模型偏差较大,无法用于中长期预测,甚至不能做短期预测等问题.从优化GM(1,1)背景值出发,通过提高背景值的构造精度,实现对传统GM(1,1)模型的改进,利用MATLAB软件编制高效的计算机程序,实现模型的模拟和预测,并将其应用于我国危险化学品事故起数及死亡人数预测.实例结果表明,改进GM(1,1)模型无论对变化平缓的低增长序列,还是变化急剧的高增长序列,都有较好的适应性,及更好的拟合和预测效果,为提高建模精度提供了新的途径.  相似文献   

5.
The evaluation of exclusion (hazard) zones around the LNG stations is essential for risk assessment in LNG industry. In this study, computational fluid dynamics (CFD) simulations have been conducted for the two potential hazards, LNG flammable vapor dispersion and LNG pool fire radiation, respectively, to evaluate the exclusion zones. The spatial and temporal distribution of hazard in complex spill scenario has been taken into account in the CFD model. Experimental data from Falcon and Montoir field tests have been used to validate the simulation results. With the valid CFD model, the mitigation of the vapor dispersion with spray water curtains and the pool fire with high expansion foam were investigated. The spray water curtains were studied as a shield to prevent LNG vapor dispersing, and two types of water spray curtain, flat and cone, were analyzed to show their performance for reduction and minimization of the hazard influencing distance and area. The high expansion foam firefighting process was studied with dynamic simulation of the foam action, and the characteristics of the foam action on the reduction of LNG vaporization rate, vapor cloud and flame size as well as the thermal radiation hazard were analyzed and discussed.  相似文献   

6.
改进GM(1,1)模型在城市环境噪声预测中的应用   总被引:1,自引:2,他引:1  
本文从传统GM(1,1)预测模型构造原理出发分析其存在的不足,指出模型适用于具有较强指数规律的序列,只能描述单调变化过程,而且预测数据序列中出现连续两个相等值时将使得a等于0,会使预测数据发散致使预测失效.文中通过采用平均斜率的概念计算a(k)序列,并利用MATLAB编程实现数据处理.广州市环境噪声污染数据的计算表明,新方法有满意的拟合和预测效果,从而为提高建模精度提供了新的途径.  相似文献   

7.
Current brief aims to introduce the concept of safety in European industrial sectors, particularly in mechanics and machinery industry. It also highlights the importance to ensure an even level of machinery safety along the European Union, setting up the appropriate frame and procedures to keep it under control. An overview over market surveillance activities for machinery (regulations, main actors and their roles) first at Community level, and secondly an approach to one of the Member States is also introduced.  相似文献   

8.
CREAM强调人在生产活动中的绩效输出不是孤立的随机性行为,而是依赖于人完成任务时所处的环境或工作条件,它通过影响人的认知控制模式和其在不同认知活动中的效应,最终决定人的响应行为。在驾驶舱内,机组的绩效输出不仅仅是人的自身行为,还依赖于其完成任务时所处的情景环境,所以CREAM方法能够结合驾驶舱环境对机组的认知差错进行分析。在飞行中,驾驶舱内机组非常重要的一个环节是判断与决策过程,这一过程中包括询问、讨论、确定方案、执行、反馈五个环节。本文将通过分析这五个环节的相互关系及影响,以明确这种讨论过程是减少机组人为差错发生的一种有益方式,然后应用CREAM的预测法对这五个环节进行定量化分析,得出机组判断与决策过程的失误概率,完成对机组认知行为的客观评价,并为以后能够定量化研究驾驶舱内飞行员认知差错提供方法的借鉴。  相似文献   

9.
为了更精确合理地对新桥硫铁矿排水方案进行优选,对利用突变理论的方法进行优化,建立突变理论和熵权法相结合的改进模型。从经济和工程量方面出发,综合考虑了影响排水方案优选的3个层次的12个指标,统计样本数据。运用熵权法分层确定同一上层变量下各指标的客观权重,导入突变理论中,建立综合评价结构模型,消除了主观因素的影响。同时运用突变理论和EM-TOPSIS进行方案优选,通过对比3种方法的优选结果,证明了改进突变理论的可靠性与合理性。  相似文献   

10.
改进LEC法在水利水电工程建设期危险源评价中的应用   总被引:3,自引:0,他引:3  
在水利水电工程建设期的安全管理中,危险源的管理处于十分重要的地位。水利水电工程施工企业通常采用作业条件危险性评价法(LEC法)进行风险评价。LEC法十分依赖评估小组的实际经验。针对LEC法的局限性,提出用于水利水电工程建设期危险源评价的改进LEC方法,以提高企业的危险源管理水平。  相似文献   

11.
为缩短启动时间,提高脱氮效果,通过添加自制生物制剂(由原土、活性污泥、草炭、鸡粪、炉渣等按比例配成)的方法对地下渗滤工艺加以改进,并对改进型地下渗滤系统的启动、微生物种群分布、脱氮效果以及运行情况进行了试验研究.结果表明:进水水力负荷6.5cm·d-1、COD的污染负荷300mg·L-1时,改进型地下渗滤系统22~25d即可完成启动过程;氨化、硝化以及反硝化细菌在进、出水口分布均匀,活性强;水力负荷4.0~8.1 cm·d-1,进水NH3-N、TN质量浓度分别为92~103 mg·L-1、108~122mg·L-1时,NH3-N的去除率96.3%~97.4%,总氮的去除率88.5%~89.8%,改进后系统处理污水的最佳水力负荷为8.1 cm·d-1.  相似文献   

12.
The fault detection of industrial processes is very important for increasing the safety, reliability and availability of the different components involved in the production scheme. In this paper, a fault detection (FD) method is developed for nonlinear systems. The main contribution consists in the design of this FD scheme through a combination of the Bayes theorem and a neural adaptive black-box identification for such systems. The performance of the proposed fault detection system has been tested on a real plant as a distillation column. The simplicity of the developed neural model of normal condition operation, under all regimes (i.e. steady-state and unsteady state), used in this case is realised by means of a NARX (Nonlinear Auto-Regressive with eXogenous input) model and by an experimental design. To show the effectiveness of proposed fault detection method, it was tested on a realistic fault of a distillation plant of laboratory scale.  相似文献   

13.
为改善我国尾矿库在线监测系统由于重建设、轻利用而导致的事故预警能力被制约的现状,以尾矿坝体变形速率监测指标为研究对象,通过引入改进云模型,根据3E规则确定尾矿坝变形监测的正常运营值边界,建立尾矿库坝体变形速率4级预警阈值确定模型,以湖北省某尾矿库为例进行实例分析。结果表明:通过提出的坝体预警阈值确定方法,可得出尾矿库坝体变形速率黄、橙、红各级预警阀值分别为10.842,16.68,25.02 mm/d;进一步与典型小概率法计算结果对比表明,所提出的尾矿坝变形速率4级预警阈值确定方法更加科学合理,可用于尾矿库重要安全监测指标预警值的确定。  相似文献   

14.
TOPSIS法在职业危害综合控制方案决策中的应用   总被引:1,自引:1,他引:0  
职业危害控制方案决策属于多属性决策,应用Topsis法对职业危害控制方案进行决策,可以满足不同工艺、不同作业条件、不同经济、技术水平企业选择适宜的职业危害控制方案的需求,以达到有效控制职业危害的目的。Topsis法用于企业职业危害控制方案进行决策具有较好的准确性、实用性,是一种较易于操作、客观的综合决策方法。  相似文献   

15.
为了实时有效监测环空带压气井的液面位置,评价环空带压气井的风险,在传统回波定位技术基础上,提出了1种基于自相关分析的气井液位声波测试方法;建立了环空液位声波测试实验系统,开展了不同起爆压力下环空液位测试实验;对检测到声波信号进行平滑降噪和自相关分析,计算液面位置,并与真实液位进行对比分析;将该方法在现场含噪声的环空带压气井液位测试中进行了应用。结果表明:该方法能够对环空液位声波测试信号中的液面反射波进行有效提取;相比较现有在测试信号平滑降噪基础上提取的液面位置,降低了计算误差;同时,该方法能够在井下噪声环境中实现微弱液面反射声波的有效提取,其处理后的信号峰值指标更为突出,提高了测试系统对液位的识别能力,便于自动识别。  相似文献   

16.
为了量化职业危害发生的可能性,并为职业病防治提供依据,利用物元分析方法,建立了高危作业有害因素控制水平的综合预警模型。为了避免人为主观因素的影响,采用简单可拓关联函数确定模型中指标权重,并以定量结果确定预警级别。实例验证表明,该模型可用于对职业危害的控制水平做出综合评价,并提供定量的预警信息。  相似文献   

17.
This study explored the unit‐level antecedents and outcomes of contingent workers' attitudes toward their temporary help services (THS) firm. It was proposed that (a) client‐orientation levels of the THS firm's full‐time staff would influence the level of support received by contingent workers, (b) staff supportiveness would be reciprocated by these workers in the form of favorable firm‐directed attitudes, and (c) contingent workers' attitudes toward the THS firm would influence two unit‐level outcomes—client reported service failure, and voluntary turnover rates of THS staff. Support was found for all the hypothesized relationships in a longitudinal study utilizing survey data gathered from 1324 full‐time employees, 570 contingent workers, and 1951 clients; and archival data on staff turnover from 46 strategic business units (SBUs) of a THS firm. These results are discussed within the context of employee–organization relationship (EOR), contingent workforce, and service management literatures. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

18.
叙述了在煤矿安全管理中运用全面质量管理的方法,如实行全员、全方位、全过程的管理等。提出了搞好全面质量管理的措施。  相似文献   

19.
布袋除尘器在烧结机机尾除尘中的应用   总被引:1,自引:0,他引:1  
介绍了用旋风除尘器、布袋除尘器组成的二级串联除尘系统在小型烧结机机尾烟气除尘中的实际应用。实际运行结果表明,该系统运行可靠,除尘效率高,系统出口含尘浓度达到了国家允许的排放标准,并针对相关问题进行了探讨。  相似文献   

20.
Data were collected from managers in 24 nations/territories on work locus of control (LOC), individualism–collectivism (I–C), and well‐being (job satisfaction, absence of psychological strain, and absence of physical strain). There were significant mean differences across samples on all five of these measures, and consistent with our hypothesis, at the ecological or sample mean level well‐being was associated with an internal locus of control. However, contrary to our hypothesis, well‐being was not associated with I–C, despite a strong correlation between I–C and LOC. Findings at the ecological level were consistent with the literature concerning the salutary effects of control on well‐being. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

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