We analyze, within a dipole model, the final, inclusive HERA DIS cross section data in the low x region, using fully correlated errors. We show that these highest precision data are very well ...described within the dipole model framework starting from Q2 values of 3.5 GeV2 to the highest values of Q2=250 GeV2. To analyze the saturation effects we evaluated the data including also the very low 0.35<Q2 GeV2 region. The fits including this region show a preference of the saturation ansatz.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Sometimes, current transformers (CTs) are saturated in power systems due to increase of flux passing through the CT core. The distorted CT secondary current can lead to maloperation of protective ...relays. In this study, a new algorithm is proposed for detection of saturation interval by analysing secondary current signal using variational mode decomposition (VMD). The VMD can decompose signals into different modes which are concentrated around centre frequencies. The start and end points of saturation regions are estimated by using decomposed modes signals. Comprehensive simulations are implemented in PSCAD/EMTDC environment while the main parameters which have direct effect on saturation levels are considered in simulation studies. The performance of the proposed method is evaluated in different conditions: light, moderate, severe and AC CT saturation conditions. The promising obtained results of real data test show that the proposed method can detect the CT saturation time intervals with high accuracy in practical applications.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The concept of saturation number was introduced by Erdős, Hajnal and Moon in 1964. Let G and F be graphs. G is F-saturated if G does not contain any copy of F, but for any edge e∈E(G¯), G+e creates a ...copy of F containing e. The saturation number sat(n,F) is the minimum number of edges overall F-saturated graphs of n vertices. The notion of weak saturation number was introduced by Bollobás in 1968. G is weakly F-saturated if G contains no copy of F, but there exists an ordering of the edges of E(G¯) such that if they are added one at a time, each edge e added creates a new copy of F containing e. Define the weak saturation number wsat(n,F) to be the minimum number of edges overall weakly F-saturated graphs on n vertices. Let D be a graph without any isolated vertex. In this paper, we show that sat(n,Ks∨D)=s2+s(n−s)+sat(n−s,D).for n≥3s2−s+2sat(n−s,D)+1. As a direct corollary, we obtain that sat(n,Fps)=s2+s(n−s)+3p−3 for n≥3s2−s+6p−5, where Fps denote the generalized fan, the join of a Ks and a matching of size p. We also give the bounds of the weak saturation number of the join of two graphs, and we show that wsat(n,Fps)=s2+2sp+2p−1,if n=s+2p,s2+s(n−s)+p−1,if n≥s+2p+1.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective To evaluate regional tissue oxygenation of the brain and preductal and postductal peripheral (muscle) tissue during immediate transition after birth, and to correlate with peripheral ...preductal and postductal arterial oxygen saturation. Study design We conducted a prospective observational study. With near-infrared spectroscopy (NIRS), changes in regional oxygen saturation of the brain (rSO2brain), peripheral preductal tissue (rSO2pre), and peripheral postductal tissue (rSO2post) were measured during the first 10 minutes of life in 59 healthy term infants after elective caesarean delivery. Fractional tissue oxygen extraction was calculated for all 3 regions. Results Mean rSO2brain increased rapidly from 44% (3 minutes) to 76% (7 minutes); thereafter no significant change occurred. Mean rSO2pre and rSO2post increased constantly from minute 3 to minute 10, from 36%(pre)/27%(post) to 66%(pre)/58%(post). Fractional tissue oxygen extraction decreased in all 3 regions during the first minutes of life. Fractional tissue oxygen extraction of the brain did not change significantly after 5 minutes, and preductal and postductal fractional tissue oxygen extraction did not change significantly after 8 minutes. Conclusions During transition, the brain had the highest saturation levels, indicating a preference of oxygen delivery to the brain. Fractional tissue oxygen extraction of the brain reached a plateau earlier compared with peripheral tissue.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Directed evolution of stereo‐, regio‐, and chemoselective enzymes constitutes a unique way to generate biocatalysts for synthetically interesting transformations in organic chemistry and ...biotechnology. In order for this protein engineering technique to be efficient, fast, and reliable, and also of relevance to synthetic organic chemistry, methodology development was and still is necessary. Following a description of early key contributions, this review focuses on recent developments. It includes optimization of molecular biological methods for gene mutagenesis and the design of efficient strategies for their application, resulting in notable reduction of the screening effort (bottleneck of directed evolution). When aiming for laboratory evolution of selectivity and activity, second‐generation versions of Combinatorial Active‐Site Saturation Test (CAST) and Iterative Saturation Mutagenesis (ISM), both involving saturation mutagenesis (SM) at sites lining the binding pocket, have emerged as preferred approaches, aided by in silico methods such as machine learning. The recently proposed Focused Rational Iterative Site‐specific Mutagenesis (FRISM) constitutes a fusion of rational design and directed evolution. On‐chip solid‐phase chemical gene synthesis for rapid library construction enhances library quality notably by eliminating undesired amino acid bias, the future of directed evolution?
Take the structure‐guided route: Application of advanced gene mutagenesis methods and strategies ensures speed and reliability in laboratory evolution of selective enzymes as catalysts in organic chemistry and biotechnology. Recent developments in novel methodology from sequence‐based to structure‐guided methods are presented in this Review.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This paper deals with the modelling of magnetic saturation in induction motors (IMs) with particular focus on the equivalent or fictitious air-gap permeance technique. Besides, an improved version of ...this technique is provided so as to account for the transient starting process and the third harmonic saturation factor in addition to the fundamental one. This is for the symmetric case. Under air-gap eccentricities, extension of both saturation models is proposed using the varying saturation factor solution. The 2D-modified winding function approach (2D-MWFA) is the base of the inductance calculation and the state equations are derived from the well-known multiple coupled circuit model (MCCM). Thanks to such considerations, skew effect, rise of the magneto-motive force (MMF) across the slots, all winding harmonics, and many faulty states can be judiciously taken into account. In summary, five derived saturation models are discussed in favour of a good handling of the saturation phenomenon in cage IMs. The work is supported by extensive simulation and experimental results of eccentricity, broken rotor bar, and combined faults.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This study investigated the T2 spectrum of hydrogen nuclear magnetic resonance (1H NMR) signals in cement paste with water-to-cement ratios (w/c) of 0.2, 0.35, and 0.5 under three different ...saturation methods (natural soak, vacuum saturation, and vacuum saturation with high pressure). The saturation degree and pore structure of the cement paste under different saturation methods has been calculated through the linear relationship between water absorption and increment of NMR amplitude intensity. The results showed that the saturation degree of the cement paste increased progressively with the duration of saturation until it reached a state of equilibrium. It can increase saturation degree and reduce the saturation time by increasing the saturation pressure, and vacuum saturation with high pressure is necessary for cement paste with lower w/c. It is important to noted that conditions such as unsaturation, natural soak, and vacuum saturation may result in incomplete water saturation, leading to a partial loss of the 1H NMR signal amplitude intensity and underestimation of porosity measurements. Considering the duration of saturation and the degree of saturation, it is recommended a saturation duration of at least 4 h with a vacuum pressure of 8 MPa for cement paste with w/c ratio of 0.2 and 0.35. For cement paste with w/c of 0.5, a saturation duration of at least 0.5 h with a vacuum pressure of 8 MPa is suggested.
•Quantifying the water saturation degree of cement-based materials by hydrogen nuclear magnetic resonance.•Degree of saturation under different saturation methods.•The water absorption of the cement paste is linearly related to the NMR amplitude intensity increment.•Vacuum saturation with high pressure can significantly increase the degree of saturation of the cement paste.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This article aims to provide a more detailed analysis and optimization of the implementation process of a recently proposed magnetic saturation model identification method for synchronous reluctance ...motors. This model identification method uses injection voltages and ensures that the motor rotor remains stationary without locking during the experimental process. The data are processed using the least-squares method. The magnetic saturation model includes both self-saturation and cross-saturation parts, which conform to the actual motor modeling requirements. It seems that most model identification tests that use injection voltage ignore the impact of deadtime effects. This can lead to incorrect magnetic flux calculation, so a compensation method is proposed in this article. Furthermore, due to the need to ensure that the injection voltage direction is correct, keeping the rotor standstill during the testing process is necessary. It is difficult to select the injected voltage value during the cross-saturation model parameters identification testing process, and there is no absolutely correct configuration method for setup the values. This article will analyze this and propose more reasonable limiting conditions. Finally, a 5-kW synchronous reluctance motor is identified through simulation and practical operation, and the magnetic saturation model of the motor is obtained.
Multispectral lidar has become a promising technology with the rise in capability of 3-D spectral imaging. However, the precise acquisition of spectral information is interfered by measurement ...geometry, namely, incidence angle and detection distance. These issues may cause discrepancy within the spectral information, thus limiting the classification capabilities of multispectral lidar. To fill this gap, a hue-saturation-intensity (HSI) color space-based method for multispectral lidar classification is proposed in this study. The proposed scheme does not require radiometric calibration, as the HSI color space is robust to spectral intensity variations within a single target. In this method, spectral data are transformed from red-green-blue (RGB) color space to HSI color space. The three components of the HSI color space are inputted for the classification. Then, a reference target-based radiometric calibration is conducted for comparison. The complex indoor scene and the random forest classifier are used for the validation. The classification results of using raw RGB data, raw HSI data, calibrated RGB data, and calibrated HSI data are compared. Results show that the raw HSI data outperform the raw RGB data in terms of classification accuracy. In particular, the raw HSI data can correct the classification error caused by the measurement geometry more effectively than the calibrated RGB data. The improvement resulting from using the HSI color space is demonstrated by both the three-wavelength multispectral lidar and the 32-channel multispectral lidar. That indicates that HSI color space is a promising tool for enhancing the classification capability of multispectral lidar.
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