城市管道天然气在土壤中扩散行为全尺度实验

为了及时发现管道天然气泄漏、快速准确判定泄漏点位置以及划定泄漏扩散影响范围,应用自主设计和构建的实验系统,开展了多组全尺度中低压埋地管道泄漏实验,揭示了管道天然气在土壤中的对流扩散基本特性,得到了其浓度场空间分布和变化规律。实验发现：①土壤中天然气浓度分布水平方向关于泄漏口基本对称,但泄漏前期其浓度分布垂直方向关于泄漏口不对称,即泄漏初始,天然气高浓度区等值线为椭圆（椭圆长轴为垂直方向）,随着泄漏时间的推移,浓度等值线出现不规则变化（在泄漏口正上方有一个明显的凸起）,且低压泄漏引起的高浓度区域凸起幅度比中压泄漏更大更明显,但随着管道天然气持续泄漏,其浓度等值线凸起也逐渐消失;②天然气浓度到达爆炸下限所需时间与距泄漏口距离呈现近似的幂指数关系;③随着管道压力、泄漏速率的增大,土壤中甲烷爆炸极限-泄漏时间特征曲线由凸形曲线变化为直线,且斜率越来越大。     

厂级信息监控系统的B/S化实现

针对当前C/S模式下SIS系统的不足,研究设计出B/S模式下的SIS系统方案,有效解决了传统SIS系统"升级难、兼容难、同步难"的问题。系统采用"浏览器-服务器-实时数据库"架构,综合利用SVG技术、JavaScript控制DOM对象模型、Ajax异步刷新技术和Java异步消息模型进行设计。经测试证明,与传统的SIS系统相比,该方案在实用性、可维护性、实时性等方面具有明显优势。     

基于有限元方法的悬空管道稳定性分析

自然灾害中的土体塌陷严重威胁埋地管道的稳定性。为了研究埋地管道在悬空塌陷区的稳定性,基于有限元方法,研究了壁厚、外径不同的埋地弯管在悬空状态下的位移、应变和应力;采用特征值屈曲理论,研究了一定条件下埋地弯管在土体塌陷时所能承受的极限长度。结果表明,减小管道在土体中的埋深、增大管道外径以及壁厚,可以有效降低管道在土体塌陷过程中的位移,管道的应力和应变均发生在塌陷区的中心和两侧固支端的位置;管道外径、壁厚的提高,可以在一定程度上抑制局部应力过高;埋地弯管在采空区的极限长度约为87 m,并且增大管道外径和壁厚可增强埋地弯管在土体塌陷过程中的抗屈曲能力。     

冀中坳陷孙虎潜山带裂缝发育特征及定量预测

为了明确冀中坳陷孙虎潜山带裂缝发育特征,通过地震、岩心及成像测井等资料归纳裂缝类型,对裂缝参数进行定量表征,分析裂缝主控因素并定量预测裂缝的分布规律。结果表明,研究区碳酸盐岩储层主要发育北东—南西向的高角度构造裂缝,裂缝充填程度较弱有效性高。单井线密度分布在1.0~6.8条/m,裂缝高度主要分布在10~40 cm。构造变形强度大、断层发育程度高的部位裂缝的发育程度越高;白云岩中平均裂缝密度为0.68条/m,裂缝最为发育;埋藏深度越低,裂缝发育强度越大,厘定出风化壳控制优质储层厚度为50~160 m。通过建立分形生长模型预测孙虎潜山带裂缝分布规律,预测结果与测井解释结果一致。     

辽河东部凹陷茨榆坨潜山油气分布规律研究

茨榆坨潜山为东部凹陷典型的太古宇潜山.根据区内潜山埋深、构造形态及主要断层的控制作用,可以划分为高、中、低三个潜山带.裂缝型储层是茨榆坨潜山的储集层,良好的储层是潜山成藏的关键.牛居—长滩洼陷为潜山提供了丰富的油源,茨东断层及不整合面做为良好的输导体系,上覆房身泡组火山岩为油气成藏提供了盖层条件.油气分布与岩性、构造有关,且有沿裂缝发育带、近油源分布的特点.     

Distribution of distinguishable objects to bins: generating all distributions

In this paper we give an algorithm to generate all distributions of distinguishable objects to bins without repetition. Our algorithm generates each distribution in constant time. To the best of our knowledge, our algorithm is the first algorithm which generates each solution in O(1) time in the ordinary sense. As a byproduct of our algorithm, we obtain a new algorithm to enumerate all multiset partitions when the number of partitions is fixed and the partitions are numbered. In this case, the algorithm generates each multiset partitions in constant time (in the ordinary sense). Finally, we extend the algorithm to the case when the bins have priorities associated with them. Overall space complexity of the algorithm is O(mklgn), where there are m bins and the objects fall into k different classes. In a companion paper, the generation of all distributions of identical objects to bins is also considered.     

Degradation mechanism of the Ru wares unearthed from the Qingliangsi site in Henan,China

The Ru kiln is a famous kiln that originated in the Northern Song Dynasty (960–1127 CE) in China. After nearly a thousand years of degradation, many ‘white spots’ have appeared on the Ru glazes, which have seriously damaged the visual aesthetic. Energy-dispersive X-ray fluorescence spectroscopy (EDXRF), X-ray diffraction analysis (XRD), optical microscopy (OM), scanning electron microscopy-energy dispersive spectrometry (SEM–EDS), Raman spectroscopy, and angle-resolved spectrum system were used to systematically investigate the composition, microstructure, and degradation morphology of the Ru ware. The degradation mechanism of the Ru glaze was investigated, showing that the heterogeneity of the glaze microstructure resulted in different degradation morphologies. The weakest part determined the overall corrosion resistance. Fine crackles of the glaze provided a fast path for corrosion. The special soil environment at the Qingliangsi site was a key influencing factor leading to the ubiquitous and severe degradation of the Ru wares. The microstructure degradation caused by chemical corrosion provided complex light-reflecting interfaces, leading to the formation of ‘white spots’ on the surface. Combined with the influence of exotic contaminants, the color and texture of the Ru glaze significantly changed, and the appearance quality seriously declined.     

Mathematical model of precision sensor for an automatic weapons stabilizer system

The mathematical model of the weapons stabilizer for mobile objects is presented, an equation of motion was obtained, and the schematic of the major components of the automated weapons stabilizer system was determined. The block diagram of the acceleration signal conversion in the sensor piezoelectric element was presented, and the method of compensating the input voltage by introduction of negative feedback based on the reverse piezoelectric effect was suggested. A technique for high-precision sensitivity axis of the piezoelectric sensor was presented.     

Are emotional objects visually salient? The Emotional Maps Database

The visual system prioritizes emotional content in natural scenes, but it is unclear whether emotional objects are systematically more salient. We compare emotional maps - created by averaging multiple manual selections of the most meaningful regions in images of negative, positive, and neutral affective valence - with saliency maps generated by Graph-Based Visual Saliency, Proto-object, and SalGAN models. We found that similarity between emotional and saliency maps is modulated by the scenes’ arousal and valence ratings: the more negative and high-arousing content, the less it was salient. Simultaneously, the negative and high-arousing content was the easiest to identify by the participants, as shown by the highest inter-individual agreement in the selections. Our results support the “affective gap” hypothesis, i.e., decoupling of emotional meaning from image’s formal features. The Emotional Maps Database created for this study, proven useful in gaze fixation prediction, is available online for scientific use.     

钢铁厂冶炼炉残铁的裸露爆破

为尽早完成高台裸露残铁的清除工程,采用爆破技术进行清除。通过局部试爆选择合理孔网参数,使用高精度导爆管雷管逐孔起爆网路,架设拦挡设施,取得了较好的爆破效果。爆破后,块度适中,碎块没有散落也没有飞出;厂房内实测振速0.76cm/s,小于安全允许振速,振动能量主要分布在20Hz以上高频部分高于建构(筑)物自振频率,未对周围建(构)筑物产生不良影响;施工用时短,为钢铁厂技改工程的提早竣工和钢厂正常生产的恢复争取了时间。残铁硬度高,钻孔速度慢,钻头、钎杆损耗大,但具有一定的可爆性,单耗仅为0.4kg/m3。可为类似工程的施工提供参考。