同轴成像激光非接触测量传感器的研究

介绍一种新型激光非接触位置测量传感器和相应的硬、软件系统、该激光测头有效克服了同类非接触式测头性度差，存在阴影效应等缺点。采用的专用线阵ＣＣＤ数据采集电路和相应的处理方法，显著地提高激光测头的测量速度和精度。该激光测头在华中Ｉ型数控加工中心上成功地实现了未知曲面的数控自动测量。     

回转曲面测量技术

针对回转体曲面，提出了一种利用三坐标测量机和回转工件台，在工件连续转动过程中，让测头沿母线运动，在圆柱坐标系中进行测量的方法．该方法具有测头的运动简单、安全、可靠性高、效率高等优点．论述了其工作原理、圆柱坐标的提取以及一些关键技术，包括测头系统的作用半径标定、转台回转轴线位置确定、被测零件的自动定心技术等．研制了由三坐标测量机、回转工件台、测头回转体和非接触激光三角法测头组成的实验系统，对易碎石膏零件进行测量，精度可以达到0．02mm．     

三维曲面激光数字化采集系统的研究

综合运胜机械、电子、光学、计算机等多学科的理论和技术，研究并开哪出激光数字化采集系统，实现了数控仿形加工中的非接触测量。基于光学三角测量原理、ＣＣＤ光电转换技术及单片机原理开发设计出了非接触的激光数字化仪。     

鞋楦三维面数控检测系统

鞋楦三维面检测系统是鞋楦ＣＡＤ／ＣＡＭ系统的一个必不可少的重要部分．本文介绍一种基于数控检测原理，利用触发式测头，具有自学习功能的智能鞋楦三维面检测系统．系统由测量台、单片机、微机及软件系统等构成．它能对新设计的鞋楦母样、或者大批生产的鞋楦进行自动、高效、精确的测量，是鞋楦ＣＡＤ／ＣＡＭ系统的一个理想的配套设备     

智能化激光扫描测径仪的研制

通过建立新的扫描测径原理数学模型和提出设置“标准棒”法测量原理提高了测量的精度和稳定性．研制的智能化激光扫描测径仪以ＭＣＳ－５１单片机为核心组成测量控制系统．该系统的硬件部分由８０３１单片机作为主机，软件编制采用相应的汇编语言，具有实时控制、实时输出功能．该仪器作为一种非接触测量仪器，可对生产线上高速运动，高温状态下的棒、线材直径进行动态在线检测．     

一种共聚焦激光测头轴线位置标定方法研究

针对在非接触式坐标测量机上所用激光测头轴线位置需要标定这一工程需要,通过测量标准圆弧,提出了一种最小距离评价方法,该方法在评价函数取得极小值的时候可以有效标定激光测头轴线的初始参考零位。实验结果验证了该方法的有效性与可靠性。     

微型五坐标测量机激光测头安装误差的标定

针对非接触式五坐标测量机激光测头安装位置误差较大且不易调整的缺点,建立了该五坐标测量机激光测头安装误差的数学模型.选取激光测头的不同姿态,通过测量实物基准的空间位置,给出了误差模型待标定参数的无约束最优化目标函数的外点法惩罚函数.通过计算个体之间的欧氏距离,剔除掉那些相似的个体,从而有效地避免了遗传算法易早熟的问题,完成了对误差模型的求解.实验结果表明,所建立的激光测头安装误差模型不仅适用于扫描测头,而且对触发测头也同样适用,可把该机的空间测量精度从(11.82+L/1 000)μm提高到(1.96+L/1 000)μm.     

非接触光学测头在金属强反射表面测量中的应用

强反射表面的高精度金属件和光学件的表面轮廓测量，是形貌检测领域的一个难点．文中提出了一种用于逆向工程领域的自由曲面非接触测量系统，其由三坐标测量机和主动式双目视觉形貌测头组成．通过摄像机标定了视觉测头，利用光学偏振技术消除了金属表面强反射光对测量的干扰．对扫描路径进行了规划，并根据金属表面加工纹理方向，选择采样策略．通过对量块表面的测量，验证了使用非接触方法测量金属强反射表面的可行性．研制测头的精度达到了0．05mm．     

薄孔壁厚和小孔径测量系统

由于相邻孔壁厚度的测量根据进刀量进行计算时精度很低，故提出了一种应用电容传感器对2个微小孔间相邻孔壁进行精密测量的系统．基于非接触式电容测孔传感器，研究了测头的电场边缘效应影响及保护环的宽度选择，设计了电容瞄准测孔传感器的测头对相邻小孔中心定位，利用电容差动测厚传感器测量孔壁，系统由1个瞄准测孔传感器和2个差动测厚传感器及三通道测量电路组成，处理数据后直接显示孔径和孔间壁厚．系统属非接触测量，无需修正测头及工件变形误差，实验证明，测量精度为0．5μm，     

被测表面特征对激光测头特性的影响

提出了基于坐标测量机,激光三角法测头,测头回转体的自由曲面非接触扫描测量方法,其中激光测头的输出值受被测表面的粗糙度,曲率以及颜色等特征的影响,存在相应的误差,为了减少这些误差,对其影响规律进行了实验研究,结果表明,表明粗糙度值太低,测头不能完成测量,原因是表面存在较强的镜面反射光,曲率越大,测量误差越大,因为光斑区域内的表面平均高度变化加大,颜色越深,测量误差越大,因为漫反射光信号过弱所致。     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.     

On Tragic Consciousness In The Works By Ernest Hemingway

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.