众和自备电站#2锅炉机组腐蚀积盐问题分析及改进对策

分析了众和自备电厂#2锅炉机组腐蚀积盐的主要原因，认为主要是由于缺乏锅炉停炉保养措施，锅炉运行时的给水除氧效果恶化，锅炉启动时的排气操作不到位等引起机组的腐蚀；由于锅炉水磷酸盐加入量过大，锅炉负荷变化幅度大等引起积盐问题。对此提出相应改进措施及建议。     

焦炉保护性停炉生产实践

论文介绍了焦炉保护性停炉过程的操作措施要点,工作步骤,测量要求,停炉后各项保护工作措施要点以及对停炉后的效果分析。     

锅炉停炉后壁温差的控制方法

对湛江奥里油发电厂DG2030/17.4-1(1)型锅炉停炉后汽包壁温差偏大的原因进行了分析,认为其主要是因停炉后汽水系统压力下降速度过快、汽包水位偏低、补水频繁、停炉后放水速度过快、强行通风进行快速冷却不当等所致.对此,提出尽可能减慢停炉后汽压下降速度、采用滑参数停炉方式,以及在维持汽包较高水位前提下尽量减少补水次数的控制对策.在采取这些对策后,停妒后汽包壁温差基本控制在允许范围内.     

循环流化床锅炉的防磨措施研究

循环流化床锅炉受热面磨损是对循环流化床锅炉正常运行三大威胁(磨损、给煤不畅、排渣困难)之一,由于磨损(受热面、耐火材料、风帽等)造成的停炉事故接近停炉总数的50%。在很长时间内成为影响循环流化床锅炉推广应用的主要障碍。     

循环流化床锅炉的防磨措施研究

循环流化床锅炉受热面磨损是对循环流化床锅炉正常运行三大威胁（磨损、给煤不畅、排渣困难）之一,由于磨损（受热面、耐火材料、风帽等）造成的停炉事故接近停炉总数的50％。在很长时间内成为影响循环流化床锅炉推广应用的主要障碍。     

一种安全实用的炉底门装置

冲天炉所用炉底门装置,是冲天炉的主要组成部分之一。其作用为:熔炼时作为炉底,此时炉底门处于关闭状态,停炉时打开炉底门放出炉内余料。但打开炉底门时,由于炉内余料大多都在1000℃左右高温状态,下落的铁水及余料落地时,火花、铁水及余料四溅,稍有处理不当将危及操作者的安全。为此,我厂曾应用过几种炉底门装置,经实践证实虽各有其特点,但对安全生产而言都存在一定程度的不可靠性,尤其下捅对开式炉底门装置。为适应安全生产,又要操作方便,必须采用一种安全适用的炉底门装置,我厂现采用的这种炉底门装置就达到了这个目的。     

锅炉炉管检漏方法的初步探讨

燃气锅炉炉管穿孔对正常供热是一种不利因素，停炉时间的长短很关键，而影响停炉时间的是怎样迅速准确的检测出穿孔炉管，常用的方法有直观目测、通风试验捡漏法和破坏性捡漏法，为防止采用破坏性检漏法，本文推荐了一种在直观目测、通风试验捡漏法基础上采用逐根炉管检漏法能够达到事半功倍的效果。     

锅炉腐蚀案例分析

就定期检验中发现的WNS0.5-0.7-Y工业锅炉严重腐蚀事件,应用电化学腐蚀原理分析其产生腐蚀的原因,提出了加强工业锅炉停炉和保护的具体措施。     

一次锅炉过热器爆管原因分析

某电厂一台130吨锅炉安装投产两年多,设备运行正常,在一次停炉检修后的一个月左右的时间里,锅炉的过热器连续出现三次爆管。     

浅析锅炉过热器改造

发电厂锅炉爆管被迫停炉造成非计划停运，严重影响发电厂安全生产及各项生产指标的完成。过热器爆破在锅炉“四管”泄露中占比较大的比例，因此正确分析过热器爆管原因，采取相应有效措施，对减少过热器爆管次数、进一步减少非计划停运有着非常重要的意义。     

Exchange rate effects of US government shutdowns: Evidence from both developed and emerging markets

We examine the exchange rate effects of US government shutdowns using historical exchange rate data covering 19 episodes of government shutdowns. We find that major currency exchange rates generally tend to appreciate vis-à-vis the US dollar, and foreign exchange volatility tends to increase in response to shutdowns. We show that the effect of shutdowns is felt most one day after a shutdown and the effect dies out for most currencies within five days of a shutdown. These results pass a range of robustness tests which control for day-of-the-week effects, model specifications, and the Global Financial Crisis.     

The effects of a plant closure on the stress levels and health of workers' wives — A preliminary analysis

In recent years an increasing amount of information leaves no doubt that the costs to the victims of plant closures are more than economic. The stress occasioned by job loss often results in ill health. These findings aside, little systematic research has been done of the consequences of unemployment for the spouses of the unemployed. In this article, a comparison is made between the effects of a closure on unemployed male employees and their wives. It is found that both groups suffer a high degree of anxiety over future job prospects and both experience a high level of stress as a result of the closure. However, for wives, anxiety, but not general stress, leads to ill health. For men, neither appears to have health implications: post-closure illness is related to illness prior to the shutdown. In one sense, two months after the closure, it can be argued that the impact of the shutdown was greater on wives than unemployed former employees.     

Exit and Upgrading in Response to Entry: The Case of Gasoline Retailing

Spatial competition models have established the importance of localized competition in determining competitive outcomes. However, few empirical studies attempt to determine to what extent actual local market conditions affect strategic decisions. This paper uses data provided by the acquisition of the Vancouver area Super‐Save chain of retail gasoline stations by ARCO to study the role of geographic space in competition, and the spatial response of the major competitors in the market to entry. The possibility of both accommodating and aggressive capacity responses by the major incumbent firms to entry are considered. While the empirical results show that proximity to ARCO increased the probability that a station shuts down, proximity to ARCO can explain only a limited amount of shutdown after ARCO’s entry. There is no evidence that incumbent firms used station locations and capacity changes to respond aggressively to ARCO’s entry with a spatial predation strategy.     

新冠肺炎疫情下我国农产品出口变化分析

近年来我国农产品出口总体呈上升趋势,水产品、蔬菜、果类及制品是优势出口农产品,且优势农产品出口目标市场稳定。受新冠肺炎疫情影响,我国农产品出口发生了一系列变化,出口额总体有所下降,水产品出口下降幅度较大,蔬菜出口量增价跌。提出稳定贸易基础,打通贸易渠道,拓展农产品出口市场,加大金融支持,扩大承保范围,企业加快转型升级等对策建议。     

Regional Patterns in Gasoline Station Rationalization in Canada

The number of gasoline stations in Canada fell by 40 % over the 1990s. Over the same period, the industry evolved from a large number of small stations with full service and automotive service bays, to large self serve stations with car washes and convenience stores. Demand and cost related theories of rationalization can explain the nationwide trends, but seem less able to explain city level variation in the timing and magnitude of rationalization. In this paper, we make use of a brand-level panel data set of station counts, shutdowns and characteristics for 12 Canadian cities from 1990 to 2005 to examine the relative importance of different region-level events and changes to the evolution of gasoline retailing. We find that market structure events and regulations are more strongly associated with the shutdown patterns of independent gasoline retailers than refinery-brand stations.     

Virtual Community Use for Packaged Software Maintenance

In this study, we investigated the use of virtual communities for involving distributed customers in the maintenance of packaged software. On the basis of an empirical study, we suggest that virtual communities can be usefully leveraged for corrective, adaptive, and perfective software maintenance. Specifically, the virtual community allowed for quick discovery of bugs and a rich interaction between developers and customers in the categories of corrective and adaptive software maintenance. However, although contributing also to the perfective category of software maintenance, this was the category in which several customer suggestions for modification were actually ignored by the developers. This implies that community use is indeed beneficial for maintenance related to coding and design errors as well as for maintenance of an adaptive character. However, it has limitations when associated with major changes such as software functionality addition or modification as those experienced in the category of perfective maintenance.     

电子商务软件维护成本估算方法研究

估算电子商务软件的年运行维护成本,对于维护人员安排和资金预算具有重要意义。通过论述电子商务的特点,从技术和非技术两个方面分析影响软件维护成本的十二条因素,以表格方式列出影响维护成本因素的工作量权重,建立了软件维护基本成本模型和改进成本模型,给出估算实例并对估算结果进行分析及给出了提高精度的方法。     

汽车维修分队能力建设评估指标体系构建与分析

详细分析了汽车维修分队能力建设评估指标体系的构建过程,提出了根据汽车维修分队能力建设本身的内涵及外延,依据有关法规,利用系统论建立评估指标的方法,给出了评估指标体系。此指标可用于对汽车维修分队建设的考核,对汽车维修分队建设具有一定参考价值。     

关于IT运维服务管理中知识管理的思考

本文主要对IT运维管理过程中的知识管理进行了探讨,首先描述了根据与流程的相关行对知识的分类以及知识在IT运维服务管理中的价值体现,进而以基于ITIL典型的四层架构运维管理系统为例,介绍如何在IT运维服务管理中从技术、流程、人员等三方面着手,开展知识管理,以有效提高IT运维管理水平、降低运维成本、实现知识价值的最大化。     

突发公共事件对电影行业影响的量化研究

人工收集和整理2012—2018年在中国市场上映的首轮院线电影信息数据,构建电影需求的嵌套logit回归模型,以新冠肺炎疫情为准自然实验,来量化突发公共事件对电影行业复产复工的影响。结果显示:第一,关于上映时间选择,在恢复营业后,如果所有因为疫情尚未上映的电影选择顺延上映能有效避免过度竞争的局面。第二,关于上映节奏控制,控制好未定档电影的上映节奏,保持适当的竞争能促进经济效益提升。其中,从11月份开始以每周两部的频率上映未定档电影的经济效益最佳。第三,关于上映方式选择,与线下播放相比,疫情期间选择线上播放能及时收回成本并有利于经济收益最大化的实现。研究结论为电影行业制定复产复工策略提供依据,为未来应对突发公共卫生事件提供参考。