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1.
郑晅  付帅  李雪 《科学技术与工程》2020,20(10):4125-4133
为了解决传统特长公路隧道通风控制系统架构的及时性、可靠性差,不能实现风机协同控制的问题,为满足隧道复杂风机网络通风运营需求,设计了一种基于信息物理系统(CPS)的特长公路隧道复杂风机网络协同控制系统。该系统由感控层、信息层、应用接入层、应用层和CPS层5个层级组成。感控层利用风机集群划分和嵌入式控制模块实现对隧道环境、交通量等因素的感知和局部控制。信息层通过对风机控制事件/信息优先级划分和基于发布/订阅方式的数据分发服务,提高数据传输可靠性和风机控制时效性;应用接入层通过CPS中间件,实现系统语义和时间的统一,提高数据利用效率,提升隧道风机控制的可操作性;应用层针对隧道运营服务一体化要求,给出了隧道运营的照明系统、供配电和消防系统和所设计的通风系统并行控制的接口;CPS层对感控层和信息层进行反馈控制,实现复杂风机的协同控制。该系统架构提升了特长公路隧道风机控制智能化、信息化水平,满足面向服务的隧道风机运营需求。  相似文献   

2.
隧道通风机的控制直接影响到通风的效果、风机的使用寿命和电能的消耗量。将变频调速技术应用到隧道通风控制中,实现风机软启动和无级调速,能延长风机的使用寿命、降低噪声和节约电能。结合风机特性和风阻特性曲线分析了变频调速的基本原理,讨论了其应用的可行性,给出了变频调速技术在公路隧道通风控制系统中的应用方法,并通过实际验证计算。结果表明,变频调速技术能保证公路隧道通风机节能、可靠、平稳的运行,降低了噪声和振动,延长了通风机的使用寿命。  相似文献   

3.
射流风机已在公路隧道、铁路隧道及地铁通风中被广为应用.正确的进行射流风机的空气动力设计可以提高通风装置效率,降低隧道通风的运营成本.通过对射流风机的空气动力特性分析,论证了射流风机叶轮所产生的静压仅仅是用于克服风机本身的内部流动阻力,与改善隧道内通风状态无关.指出在进行射流风机空气动力设计时,应使得其叶轮产生的静压尽可...  相似文献   

4.
根据大气扩散方程建立了公路隧道内空气质量方程和方程中相关参数,并导出了计算自然通风、纵向通风、全横向通风和半横向通风隧道内空气污染物浓度分布的解析解.实例计算了中国3座营运公路隧道内的CO浓度值与其实测浓度值之间有良好的线性关系,其相关系数的平方R2在0.849 9~0.923 1之间.  相似文献   

5.
为确保交通车辆在长大隧道内行驶安全性和环境的良好性,降低隧道通风系统初始投资及通风运营控制成本,该文以宁波市第一长隧道—奉化市莼湖镇石郞山隧道为研究对象,在分析国内外公路隧道通风方式的基础上,结合石郞山隧道的特点,提出相应的建议,以期显著降低风机的开停频度,节约运行成本。  相似文献   

6.
为明确车辆排放污染物浓度[PM_(2. 5)和挥发性有机化合物(volatile organic compounds,VOCs)]在山地城市隧道路段的分布特征,以重庆市内5条典型隧道为研究对象,采集了隧道洞内、洞口以及前后100 m范围内的空气污染物浓度值,分析PM_(2. 5)与VOCs在隧道路段的连续分布特征,以及土地开发强度与时段差异等对污染物浓度的影响。结果表明:隧道中段的污染物浓度最高、隧道出口处的污染物浓度次之、隧道进口处的污染物浓度最低;隧道高峰期间污染物浓度比平峰期间污染物浓度波动大,并且高峰期间污染物浓度大于平峰期间的污染物浓度;污染物浓度在郊区隧道路段最低,在商圈外围隧道路段居中,在商圈中心隧道路段最高; 5条隧道样本的通风效果普遍较差。建议优化隧道中段的通风装置,尤其是增加商圈中心隧道的风机密度,以改善加强隧道中段的通风效果、降低污染物浓度。。  相似文献   

7.
二郎山公路隧道火灾通风对策   总被引:12,自引:2,他引:12  
二郎山公路隧道全长4176m,单洞双向行驶。该隧道采用半横向通风系统,是中国目前应用半横向能系统并已建成运营的最长公路隧道。隧道的横通道不仅用于隧道的正常通风,而且在隧道发生火灾时,车辆及人员可以通过其撤离。但发生火灾时,风机运行的方向,以及各横通道隔断门的开闭对火灾控制将产生重大影响,如果发生控制错误,后果不堪设想。结合二郎山公路隧道实际工程,对火灾后的通风对策及应对措施进行了初步探讨。  相似文献   

8.
本文阐述了地下通道火灾排烟的通风系统模拟分析,烟气流过着屏蔽门时的局部阻力系数,再利用网络模型模拟地下隧道、各通风井的通风排烟量。以确定其能否满足通风排烟要求,对地下事故工况风机的设置、地下事故工况的处理预案,不同形式区间隧道通风系统对隧道内通风速度场、温度场及新风量的影响规律。研究同时对通风系统方案进行了初步的技术经济比较。本研究为分析地下通风系统的空气流动与传热提供了参考,为通风系统方案的选择。  相似文献   

9.
乌鞘岭特长隧道斜井施工通风技术   总被引:1,自引:0,他引:1  
以乌鞘岭特长隧道斜井施工通风为例,从施工环境、风量计算、风机选型、风向与风压控制等方面系统阐述了隧道施工通风技术。  相似文献   

10.
我国《公路隧道通风照明设计规范》与国外标准对隧道内CO浓度限值的设定在计算方法和取值上都存在差异.针对射流风机式及竖井送排与射流风机组合式纵向通风隧道CO浓度分布特性,基于差分形式的Coburn-Forster-Kane方程(CFK方程),拟合了两类典型纵向通风隧道正常运营CO浓度限值计算式.结果表明:尽管两类隧道具有不同的CO浓度分布特性,工程中可按相同的限值设计;对于长隧道,我国应设定更严格的限值标准.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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