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981.
Accident data play an important role in vehicle safety development. Accident data sources are generally limited in terms of how much information is provided on driver states and behaviour prior to an accident. However, the precise limitations vary between databases, due to differences in analysis focus and data collection procedures between organisations. If information about a specific accident can be retrieved from more than one data source it should be possible to combine the available information sets to facilitate data from one source to compensate for limitations in the other(s). To investigate the viability of such compensation, this study identified a set of accidents recorded in two different data sources. The first data source investigated was an accident mail survey and the second data source insurance claims documents consisting predominantly of insurance claims completed by the involved road users. An analysis of survey variables was compared to a case analysis including word data derived from the same survey and filed insurance claims documents. For each accident, the added value of having access to more than one source of information was assessed. To limit the scope of this study, three particular topics were investigated: available information on low vigilance (e.g., being drowsy, ill); secondary task distraction (e.g., talking with passengers, mobile phone use); and distraction related to the driving task (e.g., looking for approaching vehicles). Results suggest that for low vigilance and secondary task distraction, a combination of the mail survey and insurance claims documents provide more reliable and detailed pre-crash information than survey variables alone. However, driving related distraction appears to be more difficult to capture. In order to gain a better understanding of the above issues and how frequently they occur in accidents, the data sources and analysis methods suggested here may be combined with other investigation methods such as in-depth accident investigations and pre-crash data recordings. 相似文献
982.
Carl-Mikael Wiklund Frank Pettersson Henrik Saxén 《Metallurgical and Materials Transactions B》2013,44(2):447-458
The allocation of resources between several blast furnaces in an integrated steelmaking plant is studied with the aim of finding the lowest specific operation cost for steel production. In order to reduce the use of fossil fuels, biomass was considered as an auxiliary reductant in the furnace after partial pyrolysis in an external unit, as a complement to heavy fuel oil. The optimization considers raw material, energy, and emission costs and a possible credit for sold power and heat. To decrease computational requirements and to guarantee that the global optimum is found, a piecewise linearized model of the blast furnace was used in combination with linear models of the sinter-, coke-, and power plants, hot stoves, and basic oxygen furnace. The optimization was carried out under different constraints on the availability of some raw materials as well as for different efficiencies of the hot stoves of the blast furnaces. The results indicate that a non-uniform distribution of the production between the furnaces can be advantageous, and some surprising findings concerning the optimal resource allocation under constrained operation are reported. 相似文献
983.
Glass fiber reinforced polyamide (PA) 6 T/DT flame retarded with aluminum diethylphosphinate (AlPi) was tested to assess its flame retardant properties. Models for the decomposition of PA 6T/DT with and without AlPi are presented. Thermal decomposition was measured by performing TGA with Fourier transform infrared (FTIR) spectroscopy and FTIR spectroscopy in the condensed phase. Fire behavior was studied using a cone calorimeter and flammability was tested with UL 94 and the limiting oxygen index. AlPi works as an effective flame retardant for glass fiber reinforced PA 6T/DT materials, acting in the gas phase. Also observed was condensed‐phase action, which occurs especially under oxidative conditions before the samples ignite. © 2013 Society of Chemical Industry 相似文献
984.
Henrik Bangsø Nielsen Anders Thygesen Anne Belinda Thomsen Jens Ejbye Schmidt 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(2):238-245
BACKGROUND: Treatment methods for improved anaerobic digestion (AD) of waste activated sludge were evaluated. Pretreatments at moderate thermal (water bath at 80 °C), high thermal (loop autoclave at 130–170 °C) and thermo‐chemical (170 °C/pH 10) conditions prior to AD in batch vials (40 days/37 °C) were compared with inter‐stage treatments under the same conditions carried out between two separate steps of AD (19–21 days/37 °C). Combined treatment at 80 °C with CO2/ NH3‐stripping was also evaluated. RESULTS: Pretreatment at 80 °C had no effect on methane yield while inter‐stage treatment gave a 20% increase, compared with controls. Combining inter‐stage treatment with CO2/ NH3‐stripping gave an increase in pH (7.1 to 9.3), a drop in ammonia‐N concentration (910 mg‐N to 510 mg‐N) and a methane yield improvement of 31%. Pretreatment at 130 °C, 170 °C and 170 °C/pH 10 considerably increased the methane production within the first 4 days but the improvement following 40 days of digestion was only 13%, 9% and 2%, respectively. In comparison, inter‐stage treatment led to improvements of 9% (130 °C), 29% (170 °C) and 28% (170 °C/pH 10). All treatment processes increased sludge solubilization. CONCLUSION: Thermal treatment of waste activated sludge for improved anaerobic digestion seems more effective when applied as an inter‐stage treatment rather than a pretreatment. Copyright © 2010 Society of Chemical Industry 相似文献
985.
986.
Syam Nair Henrik Hagberg Rajanikant Krishnamurthy Claire Thornton Carina Mallard 《International journal of molecular sciences》2013,14(7):13858-13872
Perinatal brain damage underlies an important share of motor and neurodevelopmental disabilities, such as cerebral palsy, cognitive impairment, visual dysfunction and epilepsy. Clinical, epidemiological, and experimental studies have revealed that factors such as inflammation, excitotoxicity and oxidative stress contribute considerably to both white and grey matter injury in the immature brain. A member of the death associated protein kinase (DAPk) family, DAPk1, has been implicated in cerebral ischemic damage, whereby DAPk1 potentiates NMDA receptor-mediated excitotoxicity through interaction with the NR2BR subunit. DAPk1 also mediate a range of activities from autophagy, membrane blebbing and DNA fragmentation ultimately leading to cell death. DAPk mRNA levels are particularly highly expressed in the developing brain and thus, we hypothesize that DAPk1 may play a role in perinatal brain injury. In addition to reviewing current knowledge, we present new aspects of the molecular structure of DAPk domains, and relate these findings to interacting partners of DAPk1, DAPk-regulation in NMDA-induced cerebral injury and novel approaches to blocking the injurious effects of DAPk1. 相似文献
987.
988.
Björn Loges Albert Boddien Felix Gärtner Henrik Junge Matthias Beller 《Topics in Catalysis》2010,53(13-14):902-914
In this account the concept of using formic acid as a hydrogen storage material is presented. Catalytic reduction of carbon dioxide and heterogeneously catalyzed decomposition of formic acid to hydrogen and carbon dioxide are briefly discussed. In the main part the historic development and recent examples of homogeneously catalyzed hydrogen generation from formic acid are covered in detail. 相似文献
989.
990.
Segmentation of ARX-models using sum-of-norms regularization 总被引:2,自引:0,他引:2
Segmentation of time-varying systems and signals into models whose parameters are piecewise constant in time is an important and well studied problem. Here it is formulated as a least-squares problem with sum-of-norms regularization over the state parameter jumps, a generalization of ?1-regularization. A nice property of the suggested formulation is that it only has one tuning parameter, the regularization constant which is used to trade-off fit and the number of segments. 相似文献