Active Environments: Sensing and Responding to Groups of People

Most environments are passive– deaf, dumb and blind, unaware of their inhabitants and unable to assist them in a meaningful way. However, with the advent of ubiquitous computing – ever smaller, cheaper and faster computational devices embedded in a growing variety of “smart” objects – it is becoming increasingly possible to create active environments: physical spaces that can sense and respond appropriately to the people and activities taking place within them. Most of the early ubiquitous computing applications focus on how individuals interact with their environments as they work on foreground tasks. In contrast, this paper focuses on how groups of people affect and are affected by background aspects of their environments.     

Managing the verification trajectory

In this paper we take a closer look at the automated analysis of designs, in particular of verification by model checking. Model checking tools are increasingly being used for the verification of real-life systems in an industrial context. In addition to ongoing research aimed at curbing the complexity of dealing with the inherent state space explosion problem – which allows us to apply these techniques to ever larger systems – attention must now also be paid to the methodology of model checking, to decide how to use these techniques to their best advantage. Model checking “in the large” causes a substantial proliferation of interrelated models and model checking sessions that must be carefully managed in order to control the overall verification process. We show that in order to do this well both notational and tool support are required. We discuss the use of software configuration management techniques and tools to manage and control the verification trajectory. We present Xspin/Project, an extension to Xspin, which automatically controls and manages the validation trajectory when using the model checker Spin. Published online: 18 June 2002     

Agent Intellects: Pattern as a Form of Thought

Integrating qualities and aspects particular to their previously independent practices, the work of Ed Keller and Carla Leitao of collaborative design and research practice a|Um Studio spans scales and sites of application. The practice embodies a collective intelligence in a number of ways. At the scale of design practice the collaboration bridges the design cultures of Europe and the US. At the scale of urban practice, its large-scale planning proposals investigate forms of collective use and activity within the city. In addition, its interactive installations and gaming interfaces explore the potential of film and responsive technology to enable informational exchange and production. Copyright © 2006 Ed Keller & Carla Leitao. Published by John Wiley & Sons, Ltd     

Microscale characterization of damage accumulation in CMCs

The developing roles of damage mechanisms in the failure response of SiC/SiC minicomposites was investigated by the characterization of microscale damage accumulation with respect to microstructure. A multi-modal approach combining spatially resolved acoustic emission (AE) with tensile testing in-SEM (scanning electron microscope) was used to simultaneously examine surface (observed in-SEM) and bulk damage (monitored via AE). Strong agreement was shown between the evolving crack density estimated by AE and in-SEM measurements. The following were observed: (i) in-plane matrix content and distribution impacted crack growth; (ii) spatially-distributed matrix cracks generated varying stress-dependent AE; and (iii) certain individual cracks became more probable failure locations due to unique combinations of damage mechanisms that drove their growth. This approach enabled characterizing potential failure determinants and suggests that early damage behavior is related to certain microstructural features (e.g. surface flaws), while subsequent damage behavior is coupled to interactions of local mechanisms evolving with stress.     

Photolytic treatment of organic constituents and bacterial pathogens in secondary effluent of synthetic slaughterhouse wastewater

The reduction and degradation of total organic carbon (TOC) and bacteria from a secondary effluent of synthetic slaughterhouse wastewater using vacuum-ultraviolet (VUV) and ultraviolet-C (UV-C) processes and their combination (UV-C/VUV and VUV/UV-C) were investigated. The TOC removal rates under continuous mode operation ranged from 5.5 to 6.2%. In addition, the treatment with the UV-C/H₂O₂ and VUV/H₂O₂ processes under continuous mode operation doubled the TOC removal rates 10.8 and 12.2%, respectively. The optimum molar ratio of H₂O₂/TOC was found to be 2.5 and 1.5 for the UV-C and VUV processes, respectively. It was observed that all photochemical processes were able to totally inactivate different strains of bacteria with concentrations up to 10⁵ CFU/mL within 27.6 s. Finally, a kinetic model was developed to simulate the TOC degradation from a secondary effluent of synthetic slaughterhouse wastewater.     

Organochlorine levels in maternal and umbilical cord blood plasma in Arctic Canada

A baseline for exposure to organochlorine and metal contaminants has been established for mothers and newborns in the Northwest Territories and Nunavut areas of Arctic Canada. Maternal and umbilical cord blood plasma organochlorine levels are described for Inuit, Dene, Métis, Caucasian and Other non-Aboriginal participants. Overall, 523 women volunteered to participate by giving their written informed consent between May 1994 and June 1999, resulting in the collection of 386 maternal blood samples, 407 cord blood samples and 351 maternal/cord pairs. Nearly half of all the participants regularly smoked cigarettes, including 77% of the Inuit participants. Maternal and cord results are presented for PCBs (as Aroclor 1260 and 14 congeners) and organochlorine pesticides, including p,p'-DDT, p,p'-DDE, beta-hexachlorocyclohexane (beta-HCH), hexachlorobenzene (HCB), cis and trans nonachlor, heptachlor epoxide, oxychlordane, mirex, dieldrin and toxaphene. Maternal PCB levels (as Aroclor 1260) averaged 4.42 (+/-9.03) microg/l in Inuit, which was 3.3 times higher than those found in Dene/Métis, and 3.4 times higher than levels in Caucasians. Mean DDE levels were 2.8 times higher in the Other non-Aboriginal group (Chinese, Filipino, East Indian and multiple ethnicity) than in the Inuit group, at 3.99 microg/l and 1.42 microg/l, respectively. Cord blood PCB levels (as Aroclor 1260) averaged 1.16 (+/-2.42) microg/l for Inuit participants, which was 3.3-4 fold higher than the other ethnic groups. PCBs, p,p'-DDE and hexachlorobenzene were detected in all maternal samples, and p,p'-DDE was detected in all cord samples. Regression coefficients for maternal/cord pairs are presented for selected organochlorines. Other results from this study, including maternal and cord metals data, will be presented elsewhere.     

Redefining the stormwater first flush phenomenon

The first flush in urban runoff has been an important, yet disputed phenomenon amongst many researchers. The vast differences in the evidence could be solely due to limitations of the first flush current definition and the approach used for its assessment. There is a need for revisiting the first flush theory in the light of its practical applications to urban drainage management practices. We propose that a catchment's first flush behaviour is to be quantified by the runoff volume required to reduce a catchment's stormwater pollutant concentrations to background levels. The proposed method for assessment of this runoff volume starts by finding the average catchment pollutant concentrations for a given increment of discharged volume using a number of event pollutographs. Non-parametric statistics are then used to establish the characteristic pollutograph by pooling statistically indifferent runoff increments (known as slices) together. This allows the identification of the catchment's initial and background pollutant concentrations and for quantification of the first flush volume and its strength. The novel technique was used on seven catchments around Melbourne, Australia, with promising results. Sensitivity to the chosen increment of runoff (for which mean concentrations are calculated) indicated that when dealing with discrete flow-weighted water quality data, a suitable slice size should closely match the flow-weighting of samples. The overall sensitivity to runoff increment and level of significance was found to be negligible. Further research is needed to fully develop this method.     

生活质量与现代居住环境

预制城镇住宅系统包含了先进的技术和标准。它以经过验证符合现场施工要求的建筑构件为基础。这些构件一般是在可监控环境下预制的。然后运送到预订的现场。预制城镇住宅系统还有以下优点：建设周期短,质量更加优异,重量轻,受环境因素干扰小,施工安全,劳动力和设备要求小,为了满足不断扩大的需求,城镇住宅考虑到简单化和模数化的设计,可以有一整套灵活的建筑外形,在满足国际最高标准的同时,它还可以为本地提供质量培训的潜力。城镇住宅是一个智能化的住宅,拥有计算机化的建筑控制管理系统。通过与信息产业和钢铁工业等相关产业合作,它保持着与最新的发展同步,城市住宅系统具有零缺陷质量,它的发展是符合生态和环保要求的。