Supplier ranking by multi-alternative proposal analysis for agile projects

Changing requirements and on-going decision making along the entire project life cycle are well handled by Agile methods. However Agile projects still use evaluation methods during the RFP stage that do not fulfill the flexibility mandated by the Agile manifesto.     

相机眼：建筑中的投影机器

让·弗朗索瓦·利奥塔（Jean-Francios-Lyotard）将电影摄影术表述为对以运动进行的写作,是对电影片断的主动创作。当我们试图通过将时间切分为一系列的静态的,固定的时刻来理解运动,然后再通过某种方式将其连接时,我们便遗失了运动的整体。德勒兹认为随着蒙太奇的出现,片断便具有时间性而并非单纯的空间性.对于“固定片断＋抽象时间”的分析也将转化为对“移动片断＋时间平面”的分析。这一理念亦可通过某种方式类比于建筑,建筑师的活动与电影制作过程表现出较强的相似性。这也同样体现在“相机眼”（Camera Eye project）中。     

Low dose powdered activated carbon addition at high sludge retention times to reduce fouling in membrane bioreactors

The addition of a low concentration of PAC (0.5 g L⁻¹ of sludge, i.e. a dose of 4 mg L⁻¹ of wastewater), in combination with a relatively long SRT (50 days), to improve membrane filtration performance was investigated in two pilot-scale MBRs treating real municipal wastewater. Continuous filterability tests at high flux showed the possibility to run for 18 h at 72 L m⁻² h⁻¹ and 180 h at 50 L m⁻² h⁻¹, while significant fouling occurred without PAC. In addition, measurements of the critical flux showed an increase of 10% for this strategy. Low dosage and high retention time makes it feasible and cost effective. Further advantages with regard to permeate quality and possible micropollutants removal are currently under investigation.     

Auswirkungen von Temperatur,Schwinden und Kriechen auf Integralbrücken

Effects of temperature, shrinkage and creep on integral bridges. One of the main parameters on the design of an integral bridge is the horizontal displacement at the deck – abutment connection. As integral bridges accommodate superstructure movements without conventional expansion joints and bearings, the horizontal displacement, which can be either deck elongation or deck contraction, is one of the main differences between the design of a “classic” bridge and an integral bridge. In this article, the results on horizontal displacements of a concrete bridge deck with a total bridge length taken as free parameter varying between 20 and 180 m, caused by temperature actions and concrete time dependency aspects incl. prestress are presented. The influences of the consequences using various concrete strength classes and building sequences are included.     

Thermo-mechanical and microstructural characterisation of sodium-poly(sialate-siloxo) (Na-PSS) geopolymers

The thermo-mechanical and microstructural character of sodium-poly(sialate-siloxo) (Na-PSS) geopolymers synthesised from dehydroxylated kaolinite (metakaolinite) have been investigated. Thermal analysis by means of TG–DTA showed a single endothermic peak at 135–140 °C due to dehydration (water evolution) from the geopolymer framework. Thermal expansion measurements show that geopolymer suffers 2% shrinkage below 250 °C and is then dimensionally stable up to 800 °C. The inclusion of aggregate (α-quartz or granite) was found to reduce the shrinkage by 1% although the presence of the quartz limits the working temperature range of the composite due a to disruptive phase change. Thermal conductivity and compressive strength of Na-PSS geopolymers varied with change in chemical composition of the geopolymer as well as the amount and type of aggregate. Investigation of the microstructure by electron microscopy showed that the ratio of the starting materials influences the homogeneity of the geopolymer microstructure, which in turn leads to differences in thermal conductivity and compressive strength.     

Structural characteristics of phosphorus-doped C60 thin film prepared by radio frequency-plasma assisted thermal evaporation technique

Phosphorus doped C60 (P:C60) thin films were prepared by a radio frequency plasma assisted thermal evaporation technique using C60 powder as a carbon source and a mixture of argon and phosphine (PH3) gas as a dopant precursor. The effects of the plasma power on the structural characteristics of the as-prepared films were then studied using Raman spectroscopy, Auger electron spectroscopy (AES) and X-ray photo-electrons spectroscopy (XPS). XPS and Auger analysis indicated that the films were mainly composed of C and P and that the concentration of P was proportional to the plasma power. The Raman results implied that the doped films contained a more disordered carbon structure than the un-doped samples. The P:C60 films were then used as a coating layer for the Si anodes of lithium ion secondary batteries. The cyclic voltammetry (CV) analysis of the P:C60 coated Si electrodes demonstrated that the P:C60 coating layer might be used to improve the transport of Li-ions at the electrode/electrolyte interface.     

Characterization of various fly ashes for preparation of geopolymers with advanced applications

Fly ashes from different power stations in Australia (Collie, Eraring, Tarong) and Mongolia (4th thermal power station, Ulaanbaatar city) have been characterized by various techniques. It was determined that the Australian fly ashes are class F while the Mongolian fly ashes are class C. Due to their chemical and mineralogical differences, the fly ashes behaved differently when alkali activated to make geopolymers. The influence of various parameters on the preparation of geopolymers have been investigated and the results are used to establish a procedure for the routine manufacture of alkaline activated products. The applicability of using fly ash for building structural elements, corrosion resistant and thermally resistant materials will be presented.     

Assessing the suitability of three Australian fly ashes as an aluminosilicate source for geopolymers in high temperature applications

Fly ash characteristics cannot be assumed to be constant between power stations as they are highly dependent on the coal source and burning conditions. It is critical to understand the characteristics of fly ash in order to produce geopolymers suitable for high temperature applications. We report on the characterisation of fly ash from three Australian power stations in terms of elemental composition, phase composition, particle size, density and morphology. Geopolymers were synthesised from each of the fly ashes using sodium silicate and sodium aluminate solutions to achieve a range of Si:Al compositional ratios. Mechanical properties of geopolymer binders are presented and the effect of the source fly ash characteristics on the hardened product is discussed, as well as implications for high temperature applications. It was found that the twenty eight day strength of geopolymers is largely dependent on the sub 20 μm size fraction of the fly ash. Strength loss after high temperature exposure was found to be dependent on the concentration of iron in the fly ash precursor and the Si:Al ratio of the geopolymer mixture.     

Playing pinball with atoms

We demonstrate the feasibility of controlling an atomic scale mechanical device by an external electrical signal. On a germanium substrate, a switching motion of pairs of atoms is induced by electrons that are directly injected into the atoms with a scanning tunneling microscope tip. By precisely controlling the tip current and distance we make two atom pairs behave like the flippers of an atomic-sized pinball machine. This atomic scale mechanical device exhibits six different configurations.     

Social context and perceived effects of drugs on sexual behavior among individuals who use both heroin and cocaine.

Researchers have identified the association between the use of cocaine and sexual behavior as an important risk factor for HIV infection and have attempted to elucidate the nature of this association. Several lines of research have suggested that facilitation of sexual behavior during intoxication with cocaine may be because of the direct pharmacological effects of the drug (e.g., increase in sexual desire), whereas others have pointed to the importance of factors related to the context of drug use (e.g., opportunities for sexual behavior, expectations about the effects of the drug, social norms). The present study explored the perceived effects of cocaine and heroin on sexual behavior, as well as the social context of drug use as a function of drug type (cocaine vs. heroin), among 46 inner-city drug users who reported a history of regular use of both crack cocaine and heroin. Results indicated that compared to heroin, cocaine had deleterious effects on participants' perceived sexual desire and performance. Despite such deleterious effects on sexual behavior, cocaine was more frequently used with an intimate partner than heroin. Furthermore, participants did not differ in the extent to which they used the two drugs in other social contexts (e.g., with friends, family, or neighbors). These preliminary results suggest that the relationship between cocaine and sexual behavior, especially among long-term cocaine users, may be facilitated by opportunities for sex that exist in the context of cocaine use, rather than by the pharmacological effects of the drug. (PsycINFO Database Record (c) 2010 APA, all rights reserved)