Exploring and exploiting a historical corpus for Arabic

This paper presents a historical Arabic corpus named HAC. At this early embryonic stage of the project, we report about the design, the architecture and some of the experiments which we have conducted on HAC. The corpus, and accordingly the search results, will be represented using a primary XML exchange format. This will serve as an intermediate exchange tool within the project and will allow the user to process the results offline using some external tools. HAC is made up of Classical Arabic texts that cover 1600 years of language use; the Quranic text, Modern Standard Arabic texts, as well as a variety of monolingual Arabic dictionaries. The development of this historical corpus assists linguists and Arabic language learners to effectively explore, understand, and discover interesting knowledge hidden in millions of instances of language use. We used techniques from the field of natural language processing to process the data and a graph-based representation for the corpus. We provided researchers with an export facility to render further linguistic analysis possible.     

Nonlinearity of bituminous mixtures

This paper presents an experimental characterization of the strain dependency of the complex modulus of bituminous mixtures for strain amplitude levels lower than about \(110~\upmu\mbox{m}/\mbox{m}\). A series of strain amplitude sweep tests are performed at different temperatures (8, 10, 12 and 14°C) and frequencies (0.3, 1, 3 and 10 Hz), during which complex modulus is monitored. For each combination of temperature and frequency, four maximum strain amplitudes are targeted (50, 75, 100 and \(110~\upmu\mbox{m}/\mbox{m}\)). For each of them, two series of 50 loading cycles are applied, respectively at decreasing and increasing strain amplitudes. Before each decreasing strain sweep and after each increasing strain sweep, 5 cycles are performed at constant maximum targeted strain amplitude.Experimental results show that the behavior of the studied material is strain dependent. The norm of the complex modulus decreases and phase angle increases with strain amplitude. Results are presented in Black and Cole–Cole plots, where characteristic directions of nonlinearity can be identified. Both the effects of nonlinearity in terms of the complex modulus variation and of the direction of nonlinearity in Black space seem to validate the time–temperature superposition principle with the same shift factors as for linear viscoelasticity.The comparison between results obtained during increasing and decreasing strain sweeps suggests the existence of another phenomenon occurring during cyclic loading, which appears to systematically induce a decrease of the norm of the complex modulus and an increase of the phase angle, regardless of the type of the strain sweep (increasing or decreasing).     

智能照明系统控制网络的研究

楼宇自控系统(BAS)在照明装置上只能实现有限的控制,而面向照明系统的控制网络克服了BAS的缺陷.在阐述国内得到应用的照明系统控制网络的基础上,重点论述了欧洲安装总线和数字化可寻址调光接口两种协议的技术指标和产品特点.     

一种应用于博物馆文物展示的LED照明系统

白色发光二极管的诸多优点使其在照明领域的应用越来越广泛,将成为继白炽灯、荧光灯和气体放电灯之后新一代的光源,二十一世纪将进入以LED为代表的固体光源照明时代.尤其在博物馆文物展示照明中,白色LED光源照明的优势更显见.一般的荧光灯或者金属卤化物灯的紫外辐射会对博物馆文物造成不同程度的老化和损害,本文提出了一种应用白色LED环形光源的照明系统,使得这种损害大大降低,在博物馆文物展示中实现了绿色照明.本文给出了该系统的光学设计和理论模型,通过计算机编程得到相应的反射镜面曲线方程参数,并在光学软件(ASAP)中模拟出几何模型,进行光线追迹和数据分析,理论上证实此系统的可行性.     

1 000 MW高效宽负荷率的超超临界锅炉开发

根据反平衡法对电站锅炉各项效率损失进行分析，潜力较大的是排烟损失和未完全燃烧损失，主要影响因素有过量空气系数、排烟温度、燃烧效率；1 000 MW高效宽负荷率超超临界煤粉锅炉的开发采用低过量空气系数设计理念，在炉膛选型、受热面布置、燃烧系统设计、降低锅炉漏风等方面采取措施。与传统设计相比，50% THA负荷下锅炉效率提升了0.96%。     

头颈部血管内支架植入术后光学相干层析成像初步观察

【摘要】 目的 采用频域光学相干层析成像（FD- OCT）技术观察头颈部血管内支架植入术后周围组织结构变化。方法 对9例接受头颈部血管内支架植入术治疗3个月后头颈部血管病变患者作全脑DSA造影及病变血管内FD- OCT检查。9例患者12个血管病变处共植入支架13枚，其中颈总动脉4枚，颈内动脉5枚，椎动脉3枚，左锁骨下动脉1枚。FD- OCT观察支架有无断裂及贴壁不良，支架内斑块或血栓形成、组织脱垂，血管内膜撕裂形成夹层或内膜增生至再狭窄等。结果 8例患者成功实施FD- OCT检查，1例失败。11支病变血管12枚支架成功获取清晰FD- OCT图像，观察结果显示，12枚支架中有1枚支架部分支撑杆未能完全封闭动脉壁上瘤口；21个支撑杆贴壁不良；2枚支架内有斑块及血栓形成；6枚支架内有不同程度血管内膜增生，其中1枚支架内严重内膜增生至支架内狭窄作再次支架植入术；3枚支架内有4个不同程度组织脱垂；未发现血管内膜撕裂形成夹层。结论 FD- OCT可清晰显示头颈部血管病变支架植入术后支架内斑块或血栓形成、组织脱垂、血管内膜撕裂或增生及支架贴壁情况，其临床意义有待进一步研究。
     

采场覆岩两带与采空区自燃三带相关关系研究

为研究采煤工作面覆岩两带（冒落带、裂隙带）与自燃三带（散热带、窒息带、氧化带）的关系,通过建立覆岩运移模型,应用CDEM软件模拟分析了试验工作面采动空间上覆岩层两带的扩展过程,分析垂向方向覆岩两带分布对水平方向上垮落煤岩堆积状态的影响情况。通过现场埋管实测的手段以及氧体积分数法进行了采空区煤自燃三带的划分。研究表明,冒落带高度稳定情况下,采煤推进距离（48 m）与采空区散热带和氧化带的分界线（进风侧采空区以里50 m左右,回风侧采空区以里40 m左右）有较好的吻合关系。裂隙带高度稳定情况（顶板150 m处的岩层最大下沉值趋于基本稳定）下,采煤推进距离（126 m）与采空区氧化带和窒息带的分界线有较好的对应关系。