Safety performance functions incorporating design consistency variables

Highway design which ensures that successive elements are coordinated in such a way as to produce harmonious and homogeneous driver performances along the road is considered consistent and safe. On the other hand, an alignment which requires drivers to handle high speed gradients and does not meet drivers' expectancy is considered inconsistent and produces higher crash frequency.     

Difference Detection Between Two Images for Image Monitoring

In manufacturing industries, images are commonly used for quality control purposes. In such applications, if the quality of the products is good, then their images should be all similar to the image of a good-quality product. Therefore, comparison of images is a fundamental task in image-based quality control. This problem, however, is complicated in the sense that (1) observed images often contain noise, and (2) the related images need to be geometrically matched up first because images of different products could be geometrically mismatched because the relative positions between a camera and different products are often not exactly the same. The first issue requires a statistical method that can remove noise, and the second issue is related to the so-called image registration problem in the image processing literature. In this article, we propose effective methods for detecting difference between two images of products, and our proposed methods can accommodate both noise and geometric mismatch mentioned above. Theoretical results and numerical examples show that they can work effectively in applications.     

FOA的系统发生论

FOA通过对生物学中物种概念的研究, 以及对建筑中空间组织的分析,构建出了他们关于建筑的生成理论——系统发生论,其目的是要探寻建筑实践中内在的连续性,从而为以后的实践提供一个指导方向。文章从系统发生论的来源、组织结构以及相应的建筑作品等方面具体地分析了这一理论。     

Mechanical behavior of micaceous clays

This study aims to investigate the effect of mica content on the mechanical properties of clays.Commercially available ground mica was blended with a locally available clayey soil,at varying nica contents by mass of 5%,10%,15%,20%,25% and 30%,to artificially prepare various micaceous clay blends.The preliminary testing phase included consistency limits and standard Proctor compaction tests.The primary testing program consisted of unconfined compression(UC),direct shear(DS) and scanning electron microscopy(SEM) tests.The test results showed that the liquid and plastic limits exhibited a linear,monotonically increasing trend with increase in mica content.The rate of increase in the plastic limit,however,was found to be greater than that of the liquid limit,thereby leading to a gradual transition towards a non-plastic,cohesionless character.The soft,spongy fabric and high water demand of the mica mineral led to higher optimum water contents and lower maximum dry unit weights with increasing mica content.Under low confinement conditions,i.e.the UC test and the DS test at low normal stresses,the shear strength was adversely affected by mica.However,the closer packing of the clay and mica components in the matrix under high confinement conditions offsets the adverse effects of mica by inducing frictional resistance at the shearing interface,thus leading to improved strength resistance.     

浅析大型保障性社区“新凯家园”的规划策略

文章介绍了上海市最早建成的大型保障性住区之一"新凯家园"。在《上海市大型居住社区规划设计导则》和《上海市保障性住房建设技术导则》尚未推出的背景下,"新凯家园"为保障性住房的规划建筑设计和实践作出有益的探索,对此后保障性住区的发展具有一定的借鉴意义。     

苯丙乳液改性水泥修补砂浆的制备与性能研究

采用复配技术制备苯丙乳液改性水泥修补砂浆,并进行性能研究.探讨了聚合物乳液、偏高岭土、煅烧膨润土等外加剂对该砂浆物理性能的影响.结果表明:苯丙乳液的掺入虽然在一定程度上降低了砂浆的抗压强度,但显著改善了水泥砂浆的和易性和需水量.通过掺加偏高岭土或煅烧膨润土等火山灰活性掺合料可弥补砂浆力学性能的不足.     

Precision machining of micro tool electrodes in micro EDM for drilling array micro holes

Micro electro discharge machining (micro EDM) is suitable for machining micro holes on metal alloy materials, and the micro holes can be machined even to several microns by use of wire electro discharge grinding (WEDG) of micro electrodes. However, considering practicability of micro holes <Φ100 μm in batch processing, the controllable accuracy of holes’ diameter, the consistency accuracy of repeated machining and the processing efficiency are required to be systematically improved. On the basis of conventional WEDG method, a tangential feed WEDG (TF-WEDG) method combined with on-line measurement using a charge coupled device (CCD) was proposed for improving on-line machining accuracy of micro electrodes. In TF-WEDG, removal resolution of micro-electrode diameter (the minimum thickness to be removed from micro electrode) is greatly improved by feeding the electrode along the tangential direction of wire-guide arc, and the resolution is further improved by employing negative polarity machining. Taking advantage of the high removal resolution, the precise diameter of micro-electrode can be achieved by the tangential feed of electrode to a certain position after diameter feedback of on-line measurement. Furthermore, a hybrid process was presented by combining the TF-WEDG method and a self-drilled holes method to improve the machining efficiency of micro electrodes. A cyclic alternating process of micro-electrode repeated machining and micro holes’ drilling was implemented for array micro holes with high consistency accuracy. Micro-EDM experiments were carried out for verifying the proposed methods and processes, and the experimental results show that the repeated machining accuracy of micro electrodes was less than 2 μm and the consistency accuracy of array micro holes was ±1.1 μm.     

Tools for consistency management between design products

Consistency between different design documents is most important, as these documents are usually elaborated by different persons. Consistency means that structures within different documents “match” each other and also the values of corresponding attributes. Interactive and incremental tools for building up and maintaining consistency - so-called integrators - install fine-grained relations (semantic links) between objects of these documents. Such integrators have been investigated for some time in different application domains (Nagl, 1996).This paper deals with two extensions of integrators ( [K?rtgen, 2009a] and [K?rtgen, 2009b]). Both are devoted to speed up the (re-)integration process. The first extension makes use of the still valuable information of links damaged due to changes of documents. The second reuses consistent documents of past projects, to find out big and suitable related parts of design documents or of corresponding underlying knowledge. This paper is written for a chemical engineer and, therefore, emphasizes the tool functionality side.     

Inheritance hierarchy design in object-oriented databases

Object-oriented database schema design is still mostly an art. One of the difficulties encountered during design is typing conflicts induced by multiple inheritance. In this paper, we propose a method for treating such a kind of conflicts. Our approach to inheritance conflict solving consists of several ingredients. First, we rely on branding, to introduce ‘type equivalence by name', thus allowing a designer to distinguish between structurally similar but semantically different types. However, we offer a heuristic that does not require a designer to explicitly state branding declarations. Second, we describe various kinds of conflicts, and we offer a set of procedures that analyze a schema to discover such conflicts, classify them, offering potential solutions, if possible. The procedures have been conceived for a design system that allows a designer maximum flexibility, while guiding him/her to a correct design.     

Rheological properties of African yam bean (Sphenostylis stenocarpa Hochst. Ex A. Rich.) calcium proteinate and isoelectric protein isolates

The rheological characterizations of African yam bean (Sphenostylis stenocarpa) protein dispersions were investigated. Isoelectrically precipitated protein-IP_alk and IP_salt isolates obtained from alkaline and salt extractions respectively were more soluble than calcium precipitated proteins (CaP_alk and CaP_salt) at pH 3, 7 and 8. Regression analysis showed that Power law, Casson and Bingham rheological models adequately described rheological behaviors of S. stenocarpa protein dispersion. However, Power law gave the best fit. The flow behavior indices (n), at different ionic strength, pH, and temperature media were less than unity, indicating that S. stenocarpa protein dispersion exhibited pseudoplastic behaviors under the conditions tested. Salt extracted proteins were more pseudoplastic than alkali extracted counterpart with n for salt extracted proteins (IP_salt & CaP_salt) lower than that of alkali extracted protein (CaP_alk & CaP_salt). This is a numerical indication that salt extracted S. stenocarpa proteins were of larger shear-thinning tendency than the alkali extracted proteins. The consistency coefficients, k of isoelectrically precipitated protein (0.305-0.327 Pasⁿ) were significantly (P < 0.05) higher than that of calcium proteinates in the range ranged 0.167-0.180 Pasⁿ. Both isoelectrically precipitated proteins and calcium proteinates exhibited yield stress, however, isoelectrically precipitated S. stenocarpa protein exhibited significantly (P < 0.05) higher yield stress (0.275-0.308 Pa) than the calcium proteinates (0.148-0.165 Pa). The effect of temperature on apparent viscosity of the proteins was evaluated using an Arrhenius-type equation. The activation energies (E_a) obtained were in the range 33-51.2 and 42.6-55.5 Jmol⁻¹ for calcium proteinate and isoelectrically precipitated protein respectively.