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1.
利用专业噪声测量设备及噪声频谱分析设备,对地铁站附属地下餐饮空间区域噪声进行监测,绘制噪声小时频谱。经分析发现地铁附属地下餐饮空间声环境会受到客流、空间位置及餐铺建筑结构影响,因此在该类空间进行降噪设计中应充分考虑这些因素的影响。  相似文献   
2.
Thermal runaway hazard assessment provides the basis for comparing the hazard levels of different chemical processes. To make an overall evaluation, hazard of materials and reactions should be considered. However, most existing methods didn't take the both into account simultaneously, which may lead the assessment to a deviation from the actual hazard. Therefore, an integrated approach called Inherent Thermal-runaway Hazard Index (ITHI) was developed in this paper. Similar to Dow Fire and Explosion Index(F&EI) function, thermal runaway hazard of chemical process in ITHI was the product of material factor (MF) and risk index (RI) of reaction. MF was an indicator of material thermal hazards, which can be determined by initial reaction temperature and maximum power density. RI, which was the product of probability and severity, indicated the risk of thermal runaway during the reaction stage. Time to maximum rate under adiabatic conditions and criticality classes of scenario were used to indicate the runaway probability of the chemical process. Adiabatic temperature rise and heat of the desired reaction and secondary reaction were used to determine the severity of runaway reaction. Finally, predefined hazard classification criteria was used to classify and interpret the results obtained by this method. Moreover, the method was validated by case studies.  相似文献   
3.
Most petrochemical units run under extreme conditions, such as high temperatures, pressures, and speeds. Consequently, the equipment operators may commit errors because the startup and shutdown processes usually involve complicated operation steps; moreover, the operators may lack experience in handling abnormal situations. Misoperation can lead to accidents, including fires and explosions. Thus, risk analysis for process operations and the development of preventive measures have become an effective means of avoiding misoperation-related accidents. However, it is challenging to ensure the comprehensiveness of risk-analysis results. In this paper, we present a method for misoperation monitoring and early warning in the startup and shutdown processes of petrochemical units. The mechanisms of misoperation occurrence are summarized based on investigations of serious accidents in the recent past. Knowledge regarding the mechanisms of misoperation is crucial for the risk analysis of petrochemical units. The potential risk information, such as causes, adverse consequences, key monitoring parameters, and prevention control solutions, should be acquired and be employed to construct an early-warning knowledge database. Furthermore, misoperation judgment rules need to be formulated to identify misoperations. The data obtained from the monitoring module, misoperation judgment rules, and analysis results can aid in developing schemes to avoid possible abnormal situations. This paper reports a misoperation monitoring and early-warning system for a hydrogenation unit. As demonstrated, conducting risk analysis to determine the potential operational risks and formulating misoperation judgment rules to analyze the process data are essential for enabling early warning. The application of this method will contribute to operational guidance, economic loss reduction, and accident avoidance.  相似文献   
4.
Drawing from signaling theory, we propose a work passion transfer model where leaders' passion is transmitted to employees through the former's leadership style and is contingent on employees' perceived importance of performance to self-esteem (IPSE). Data from 201 supervisor–employee dyads from the health-care industry show that leaders' harmonious passion led to employees' harmonious passion through charismatic leadership, whereas contingent reward leadership accounted for the transfer of obsessive passion; IPSE did not play a moderating role for either form of passion. Results from a supplementary study further reveal that the link between leadership and employee passion operated through employees' perception of leader passion and that employees' IPSE accentuated for the relationship between perceived leader obsessive passion and employees' obsessive passion. This study advances research in work passion, leadership, and signaling theory and provides important implications for managerial practice.  相似文献   
5.
The rapid development of technology has made it easier to distribute products directly, and many enterprises excel at executing a multi-channel strategy to distribute products. The introduction of direct channel adds a new competition dimension to the enterprises. This paper considers three market channel structures: R-Channel, D-Channel and H-Channel. In R-Channel, both new products and remanufactured products are sold through a retailer. In D-Channel, new products are sold through retailers and remanufactured products are sold directly to consumers. In H-Channel, new products are sold through retailers, while remanufactured products through dual channel. Using the game theory, we obtain and analyse the equilibrium prices, market demands and the profits gain under these three settings. At the same time, the influence of consumers’ willingness to pay on the environment performance is researched. Our results show that the manufacturer prefers H-Channel. By introducing the direct channel the manufacturer is always economically better off, but it is not for the retailer. The numerical simulation also confirms the theoretical analysis and shows that H-Channel has advantages of economic benefit and environmental performance. It is feasible for practical application.  相似文献   
6.
In line with the resource curse literature, this paper examines the effect of oil dependency on the disparities in access to electricity between urban and rural areas in Africa, conditional on the quality of political institutions. Based on data from 36 African countries over the period 2000–2017, our investigation suggests that oil rents (% of GDP) increase urban–rural disparities in access to electricity. However, the quality of institutions shapes the effect of oil dependency on these disparities. Specifically, a 10% increase in the institutional quality score reduces the adverse effects of oil rent on electricity access disparity by around 19%, and the negative impact of oil dependency on urban–rural disparities is reversed when institutional quality reaches a score of 52% on a scale from 0 to 100. The robustness tests support these results and call for strengthening the quality of institutions to overcome the resource curse in Africa.  相似文献   
7.
为揭示安全信息认知对员工心理安全感的影响,把握信息时代背景下心理安全感的研究趋势。基于安全信息认知的背景与特征,构建心理安全感的安全信息认知流程模型。通过描述安全信息对心理安全感的影响机理,从需要、动机、意识、期望剖析心理安全感的安全信息认知动力,归纳心理安全感的安全信息认知偏好,并从风险管控、安全氛围、安全管理落地、安全防护措施设计、员工安全生产积极性方面论述心理安全感在企业的应用对策。研究表明,员工安全信息认知对其心理安全感具有重要影响,是引起心理安全感波动的关键因素,也为心理安全感在企业的应用提供指导。  相似文献   
8.
张军 《环境与发展》2020,(4):185-186
随着经济和社会的不断发展,地球的环境正在遭受着严重的侵害,关于环境的问题也日益显现出来,比如全球变暖、雾霾等现象。本文分析了空气污染的因素、气象要素对空气质量的影响,并提出了防治空气污染的对策。  相似文献   
9.
For lack of an extinguishing agent with high-efficiency, non-toxic and environmentally friendly, a new type of extinguishing agent was fabricated to solve such an urgent problem. In this study, the zinc borate (ZB) and ferrocene (Fe(Cp)2) were utilized as two additives for extinguishants to suppress combustion reaction and the toxicity of the tail gas was detected. The mass fraction of ZB corresponding to the optimal inhibitory effect was determined to be 0.5–1.5%, by contrast, the optimum interval of Fe(Cp)2 was detected as 0.5–1.0%. Similarly, with the increasing proportion of the two additives, the homologous inhibitory action was gradually weakened. From the perspective of thermogravimetric analysis (TGA), it was indicated that the ZB accelerated the pyrolysis process of the extinguishant, making its thermal decomposition process more thoroughly. Meanwhile, the differential scanning calorimetry (DSC) demonstrated that the decomposition efficiency was markedly improved when the amount of ZB was maintained at 0.5–1.5%. Besides, the tail gas tests were implemented to assess the extent of toxic and harmful properties. In terms of the carbon monoxide (CO) and carbon dioxide (CO2) generated, once the mass fraction of ZB and Fe(Cp)2 was less than 1.5% and 1.0% respectively, the concentration of CO and CO2 was distinctly lower than that without additives. Moreover, the inhibitory ability on nitrogen oxides (NOx) was enhanced when the mass fraction of the two additives was kept below 1.0%. The results confirmed that a more practical extinguishant was proposed and it can provide guidance for the application and development of extinguishants.  相似文献   
10.
以JL污水处理厂设备管理优化过程为例,充分吸取LCC,TPM中的先进思想,以设备运行可靠性及设备维护经济性为追求目标,建立了设备管理优化体系。流程体系上,通过建立作业指导文件,建立标准化维修程序,对于操作过程及时进行记录,建立可视化、可追溯的管理方法;指标体系上,根据设备重要性及运行状况,确定设备风险指数,分级管理;建立控制指标,并动态调整;管控体系上,建立设备“户口”,对设备的维护、保养、使用等信息进行全面登记;考核设备维护的全面性、及时性、可靠性、合规性;重视设备维护的预计与预警;技术体系上,通过设备监测仪器的使用,对设备运行状况定量化。通过不断推进设备预防性维护工作,设备完好率不断提升,仪表完好率从2016年的97.34%,96.55%水平,分别提升至99.08%,98.72%;维护费用也保持在较低水平,检修费与资产比例在实施的前两年分别降至1.49%,0.85%,实现了污水处理厂节能降耗及运行可靠性的强化。  相似文献   
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