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51.
Kati Huttunen Anna J. Wlodarczyk Jenni Tirkkonen Santtu Mikkonen Martin Tubel Esmeralda Krop Jos Jacobs Juha Pekkanen Dick Heederik Jan‐Paul Zock Anne Hyvrinen Maija‐Riitta Hirvonen Rachel Adams Tim Jones Ralf Zimmermann Kelly BruB 《Indoor air》2019,29(2):299-307
Exposure to moisture‐damaged indoor environments is associated with adverse respiratory health effects, but responsible factors remain unidentified. In order to explore possible mechanisms behind these effects, the oxidative capacity and hemolytic activity of settled dust samples (n = 25) collected from moisture‐damaged and non‐damaged schools in Spain, the Netherlands, and Finland were evaluated and matched against the microbial content of the sample. Oxidative capacity was determined with plasmid scission assay and hemolytic activity by assessing the damage to isolated human red blood cells. The microbial content of the samples was measured with quantitative PCR assays for selected microbial groups and by analyzing the cell wall markers ergosterol, muramic acid, endotoxins, and glucans. The moisture observations in the schools were associated with some of the microbial components in the dust, and microbial determinants grouped together increased the oxidative capacity. Oxidative capacity was also affected by particle concentration and country of origin. Two out of 14 studied dust samples from moisture‐damaged schools demonstrated some hemolytic activity. The results indicate that the microbial component connected with moisture damage is associated with increased oxidative stress and that hemolysis should be studied further as one possible mechanism contributing to the adverse health effects of moisture‐damaged buildings. 相似文献
52.
Panu Tanninen Ville Leminen Sami Matthews Mika Kainusalmi Juha Varis 《Packaging Technology and Science》2018,31(5):369-376
Three‐dimensional forming of paperboard is commonly done by a press forming process, which has been widely researched. However, the process cycle of the press forming of paperboard trays has not yet been completely optimized due to limited adjustability and unsophisticated mechanical structure of commonly used forming equipment. The object of this study is to optimize the force curve of stroke to improve product quality without compromising the production rate using LUT Adjustable Packaging Line prototype for practical evaluation of formability and multibody dynamics software MSC Adams for simulation. Several process parameters were investigated with different process cycles to study their effect on the quality of the formed products. With optimized male mould speed, acceleration and speed of the blank could be reduced, which led to significantly reduced rupturing tendency without compromising the production speed. It was also found that a constant blank holding force should be used to achieve acceptable tray quality, although this results in a significantly increased surface pressure applied to the formed substrate. It was also discovered that a novel male mould attachment, which included a pressing force adjustment system that utilized a spring set with an adjustable preload, made it possible to control the force distribution between different forming tools during the dwelling phase of the process cycle in an improved way. Utilization of the method used in this paper leads to a better tray quality without compromising the production efficiency. Furthermore, this can increase the number of possible package applications for sustainable materials, such as paperboard. 相似文献
53.
Jari Rosti Juha Koivisto Paola Traversa Xavier Illa Jean-Robert Grasso Mikko J. Alava 《International Journal of Fracture》2008,151(2):281-297
The dynamics of a “peeling front” or an elastic line is studied under creep (constant load) conditions. Our experiments show
in most cases an exponential dependence of the creep velocity on the inverse force (mass) applied. In particular, the dynamical
correlations of the avalanche activity are discussed here. We compare various avalanche statistics to those of a line with
non-local elasticity, and study various measures of the experimental avalanche-avalanche and temporal correlations such as
the autocorrelation function of the released energy and aftershock activity. From all these we conclude, that internal avalanche
dynamics seems to follow “line depinning”-like behavior, in rough agreement with the depinning model. Meanwhile, the correlations
reveal subtle complications not implied by depinning theory. Moreover, we also show how these results can be understood from
a geophysical point of view. 相似文献
54.
Workflow Concurrency Control 总被引:5,自引:0,他引:5
55.
Juha Häkkinen Timo Rahkonen Juha Kostamovaara 《Analog Integrated Circuits and Signal Processing》1998,15(1):71-83
Two integrated direct I/Q modulators suitable for directupconversion with an output frequency of 950 MHz and baseband frequencies of60 to 500 kHz are fabricated in a 1.2 µm and 0.8 µm BiCMOSprocess, respectively, and their performance under various operatingconditions is discussed. The modulators use different phase shiftertopologies, one of which is based on digital CML latches and the other ondifferential pairs with resistive and capacitive emitter degeneration. Bothcircuits are operated using a single 5 V supply and they consume 50 mA or115 mA depending on the topology. The main properties of the CML modulatorare, for example, an output power of –11 ± 0.5 dBm at 100 MHzand –15 ± 2.25 dBm at 950 MHz over the temperature range of–10 to +85°C, LO suppression of 38 dBc and image rejection of41 dBc. 相似文献
56.
This study was designed to investigate the effects of three countermeasures – landscaping, building a fence and prohibitive signs – on the frequency of trespassing, which in this case means crossing the track at places where it is forbidden. At each location the official route was no more than 300 m away. The main results showed that the effect of each countermeasure on the frequency of trespassing was statistically significant. Specifically, the fencing reduced trespassing by 94.6%, followed by landscaping (91.3%) and prohibitive signs (30.7%). The majority of illegal crossings were committed alone and the persons trespassing were mostly adults and men. In addition, the results demonstrated some tendencies of how the effects of the selected countermeasures can vary with the characteristics of the trespassers. The main implication of this study is that the building of physical barriers such as landscaping or fencing is recommended for reducing trespassing. However, if the required resources are not available or the site is not suitable for such measures, the use of prohibitive signs is recommended. Further, there is a need to tailor the countermeasures to the characteristics of the trespassers in order to ensure that the most appropriate countermeasures are applied. 相似文献
57.
In this study, the ozone gas-liquid mass transfer into water in a bubble column was investigated for different pH values. The ozone volumetric mass transfer coefficient and the Henry's coefficient were determined simultaneously by parameter estimation using a nonlinear optimization method. A sensitivity analysis was conducted to obtain information on the reliability and identifiability of the estimated parameters. A minor dependence of the Henry's law constant on pH was detected at the pH range 4 to 9. 相似文献
58.
59.
Eero Eloranta Juha Hynynen Heikki Hämmäinen Juha Jahkola Ari Kyhälä Juha Räisänen 《Computers in Industry》1985,6(6):413-425
An end-user oriented workbench approach in the design of distributed production management systems (DPMS) is presented. We shall also deal with models and design of DPMS. Changes anticipated in design processes, roles and professionality required are discussed. In fact, complete structural rearrangements in the design of production management systems (PMS) are expected towards the end of this decade. The ideas presented are based on an on-going research project at Helsinki University of Technology (the so-called HUTDPMS project). 相似文献
60.
In this article, we considered the recognition of unknown shapes by maximum likelihood methods. The contour of a shape is
represented by its centroidal profile, and it is fitted by a circular autoregressive model. Two different shape recognition
problems are considered: the decision on the similarity of two unknown shapes, and the classification of an unknown shape
as one of many known shapes. Maximum likelihood decision rules for these two cases are derived. The decision rules are invariant
to translation, rotation, and size change after normalizing the estimates.
The developed algorithms are applied to classify eight classes of machine parts and eight classes of aircraft shapes. For
each class, 60 to 80 samples are generated by rotating and dilating the original shape. In the experiment, more than 98% of
machine parts are classified correctly, and more than 97% of aircraft shapes are correctly classified. This result is better
than previous model-based approaches.
Partially supported by the National Science Foundation under the grant IRI-8809391. 相似文献