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81.
E.O. Rukke E.F. Olsen T. Devold G. Vegarud T. Isaksson 《Journal of dairy science》2010,93(7):2922-2925
A rapid spectroscopic method to determine total protein in bovine and buffalo milk using UV spectra of guanidine-hydrochloride mixed milk has previously been reported and validated. The method was based on mixed calibration samples and univariate calibrations of fourth derivative (4D) spectra. In this study the same method was compared and tested for determination of total protein in goat milk. Calculations based on multivariate calibration (partial least squares regression) on full spectra of goat milk were used. The method was tested on 2 UV instruments. The comparison resulted in a significantly more robust (i.e., better) transferability between UV instruments for the partial least squares regression method on full spectra compared with previous univariate calibration of 4D spectra. Local (1 instrument) calibrations gave similar, significantly not different (chi-squared test) cross-validated prediction error results for the 2 methods. It can be concluded that there is no need for fourth derivation. Partial least squares regression on full spectra was equal or superior to using the 4D spectra. 相似文献
82.
A multiagent framework for coordinated parallel problem solving 总被引:1,自引:1,他引:0
Today’s organizations, under increasing pressure on the effectiveness and the increasing need for dealing with complex tasks
beyond a single individual’s capabilities, need technological support in managing complex tasks that involve highly distributed
and heterogeneous information sources and several actors. This paper describes CoPSF, a multiagent system middle-ware that
simplifies the development of coordinated problem solving applications while ensuring standard compliance through a set of
system services and agents. CoPSF hosts and serves multiple concurrent teams of problem solving contributing both to the limitation
of communication overheads and to the reduction of redundant work across teams and organizations. The framework employs (i) an interleaved task decomposition and allocation approach, (ii) a mechanism for coordination of agents’ work, and (iii) a mechanism that enables synergy between parallel teams. 相似文献
83.
Identifying short and long range change points in an observed time series that consists of stationary segments is a common problem. These change points mark the time boundaries of the segments where the time series leaves one stationary state and enters another. Due to certain technical advantages, analysis is carried out in the frequency domain to identify such change points in the time domain. What is considered as a change may depend on the time scale. The results of the analysis are displayed in the form of graphs that display change points on different time horizons (time scales), which are observed to be statistically significant. The methodology is illustrated using several simulated and real time series data. The method works well to detect change points and illustrates the importance of analysing the time series on different time horizons. 相似文献
84.
85.
Time-resolved and time-averaged chirp measurements of a quarter-wave shifted 1.53-μm DFB laser with a high-coupling coefficient are presented, showing a slow-steady shift towards shorter wavelengths lasting 1.5 ns after the laser is turned on. A simple method of screening for this phenomenon is presented. Transmission on a regular single-mode fiber reveals the effect of pattern-dependent pulse compression causing severe performance degradation in a long-haul NRZ (nonreturn-to-zero) system, but improving that of an RZ system 相似文献
86.
Does the aging of tenured academic staff affect the research performance of universities? 总被引:1,自引:0,他引:1
This paper examines the common contentions that the collective aging of tenured academic staff has negative effects on research
performance of universities due to (a) negative effects of aging in itself, and (b) to a lack of newcomers who could revitalise
the research. Data on academic staff and research at Norwegian universities over two decades have been used to examine these
contentions. While older staff published less than their younger colleagues two decades ago, no differences in productivity
are found today. Furthermore, during this period, a large increase in the number of post-doctoral fellows and PhD students
has taken place, compensating for the aging of tenured staff. 相似文献
87.
Kinetics of manganese ore reduction by carbon monoxide 总被引:8,自引:0,他引:8
A step has been made in the direction of understanding the fundamental chemical processes taking place inside electric are
furnaces producing manganese alloys. The reduction of higher manganese oxides to MnO by carbon monoxide has been studied in
the temperature range 700 °C to 1100 °C. A topochemical pattern with a single shrinking core inside the ore particles has
been observed in most cases. It has been found that the reduction of some manganese silicates (braunite minerals) is influenced
by reaction interface kinetics, whereas the reduction rate of manganese oxides (bixbyite and hausmannite) is mostly determined
by product shell pore diffusion. Sintering kinetics and the extent of natural porosity determine the product shell pore diffusivity.
As the melting point of the reaction product is approached, rapid sintering leads to a decrease in diffusivity. 相似文献
88.
The vapour pressure and activity of manganese were determined by a transportation method for carbon‐saturated Mn‐Si‐C alloys with different Si contents. 108 individual experiments were carried out in a vertical graphite tube furnace, normally at 1500 °C. Modified Gibbs‐Duhem relations were proposed to calculate the corresponding silicon activities. The present results agree well with similar studies for carbon‐saturated Mn‐Si‐C alloys. 相似文献
89.
Odd Jostein Svendsli 《今日电子》2010,(1):28-31
锂离子电池由于拥有能量密度高、电压高、自放电率低,以及无记忆效应等优势,因而逐渐成为使用充电电池的便携应用产品的常用技术。 相似文献