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941.
S Winkler E Saracevic J-L Bertrand-Krajewski A Torres 《Water science and technology》2008,57(10):1651-1658
In situ spectrometers are comparable robust instruments and can be operated long term with relatively low maintenance demand. The decisive factor for their applicability is the development of a medium and installation location specific correlation model, which estimates the concentration of the requested target parameter from the measured absorption values. In some cases it might turn out, that the development of a single site specific correlation model is not sufficient, due to frequent and substantial variations of the (waste) water composition.In order to assess the total uncertainty of in situ spectrometry, a comprehensive lab test was carried out. It includes a detailed investigation of the uncertainty of CODreference methods (DIN and small tube tests), a precision analysis of the absorption spectra and the impact of those two factors on the total uncertainty of the COD(EQ) correlation model. 相似文献
942.
943.
Matthias Transier Holger Füßler Jörg Widmer Martin Mauve Wolfgang Effelsberg 《Wireless Networks》2007,13(4):447-460
In this paper we present Scalable Position-Based Multicast (SPBM), a multicast routing protocol for ad-hoc networks. SPBM
uses the geographic position of nodes to provide a highly scalable group membership scheme and to forward data packets in
a way that is very robust to changes in the topology of the network. SPBM bases the forwarding decision on whether or not
there are group members located in a given direction, allowing a hierarchical aggregation of membership information. The farther
away a region is from an intermediate node, the higher the level of aggregation for this region should be. Because of aggregation,
the overhead for group membership management scales logarithmically with the number of nodes and is independent of the number
of multicast senders for a given multicast group. Furthermore, we show that group management overhead is bounded by a constant
if the frequency of membership updates is scaled down with the aggregation level. This scaling of the update frequency is
reasonable since the higher the level of aggregation is, the lower the number of membership changes for the aggregate will
be. The performance of SPBM is investigated by means of simulation, including a comparison with ODMRP, and through mathematical
analysis. We also describe an open source kernel implementation of SPBM that has been successfully deployed on hand-held computers. 相似文献
944.
在该系统中,一个运行在本地PC上的Java程序,读取游戏杆的数据,通过蓝牙连接来控制一个装有4只发动机的模型飞机的飞行.作为设计的第一步,模型飞机是在一台远端PC上仿真的,两台PC以蓝牙方式连接.文中建立了系统的控制原型,定义了应用层的协议,给出了系统的流程图,并对程序包进行了简单的描述.这一设计可用于模型飞机的实际控制,只要将远端程序移植到模型飞机上的微控制器,而本地程序无需作多大的修改. 相似文献
945.
Séance-room and other large-scale psychokinetic phenomena have fascinated humankind for decades. Experimental research has reduced these phenomena to attempts to influence (a) the fall of dice and, later, (b) the output of random number generators (RNGs). The meta-analysis combined 380 studies that assessed whether RNG output correlated with human intention and found a significant but very small overall effect size. The study effect sizes were strongly and inversely related to sample size and were extremely heterogeneous. A Monte Carlo simulation revealed that the small effect size, the relation between sample size and effect size, and the extreme effect size heterogeneity found could in principle be a result of publication bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
946.
H. B?sch, F. Steinkamp, and E. Boller's (see record 2006-08436-001) meta-analysis, which demonstrated (a) a small but highly significant overall effect, (b) a small-study effect, and (c) extreme heterogeneity, has provoked widely differing responses. After considering D. B. Wilson and W. R. Shadish's see record 2006-08436-002) and D. Radin, R. Nelson, Y. Dobyns, and J. Houtkooper's see record 2006-08436-003) concerns about the possible effects of psychological moderator variables, the potential for missing data, and the difficulties inherent in any meta-analytic data, the authors reaffirm their view that publication bias is the most parsimonious model to account for all 3 findings. However, until compulsory registration of trials occurs, it cannot be proven that the effect is in fact attributable to publication bias, and it remains up to the individual reader to decide how the results are best and most parsimoniously interpreted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
947.
948.
Gerard Giraud Holger Schulze Till T. Bachmann Colin J. Campbell Andrew R. Mount Peter Ghazal Mizanur R. Khondoker Alan J. Ross Stuart W. J. Ember Ilenia Ciani Chaker Tlili Anthony J. Walton Jonathan G. Terry Jason Crain 《International journal of molecular sciences》2009,10(4):1930-1941
Quantum dot (QD) labeling combined with fluorescence lifetime imaging microscopy is proposed as a powerful transduction technique for the detection of DNA hybridization events. Fluorescence lifetime analysis of DNA microarray spots of hybridized QD labeled target indicated a characteristic lifetime value of 18.8 ns, compared to 13.3 ns obtained for spots of free QD solution, revealing that QD labels are sensitive to the spot microenvironment. Additionally, time gated detection was shown to improve the microarray image contrast ratio by 1.8, achieving femtomolar target sensitivity. Finally, lifetime multiplexing based on Qdot525 and Alexa430 was demonstrated using a single excitation-detection readout channel. 相似文献
949.
950.
Robert Vaßen Zeng Yi Holger Kaßner Detlev Stöver 《Surface & coatings technology》2009,203(15):2146-2149
Highly porous TiO2 coatings have been produced by suspension plasma spraying on ITO coated glass substrates. The deposition process could be optimized so that fine/nano grained highly porous coatings were obtained. Mean crystallite sizes well below 50 nm could be achieved in the coatings for the anatase phase.Special emphasis was on the establishment of a high volume fraction of the desired anatase phase. The best coatings showed values of about 90% of anatase phase.With these coatings photovoltaic cells could be produced. Different levels of layer thickness and porosity as well as contents of anatase phase have been investigated.In the paper details on the microstructure of the cells as well as the photovoltaic performance will be given. 相似文献