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The operations of the operators are important for nuclear safety, but conventional operating experience feedback and common data-driven methods make it difficult to explicitly find valuable information hidden in these operational sequences that can help the operator to provide advice at the operational level. During the nuclear power plant (NPP) operation, a large amount of historical operating data is accumulated, which records the operational sequences of the operators and the state parameters of equipment. Therefore, this paper proposes the use of association rule techniques to mine the NPP operating data to discover the operational characteristics of operators and reveal their possible impact on the NPP operation. This work helps to improve the operational performance of operators and prevent human-factor events. To this end, the concept of state switching values for describing the operating states of NPPs is proposed to enable the proposed method to be adapted to different practical application scenarios. A sequence segmentation method is proposed to be able to transform historical NPP operating data into a sequence data set for association rule mining. Furthermore, an ensemble algorithm based on sequence pattern mining and sequence rule mining and its postprocessing method are designed. The empirical study was carried out using 20 batches of historical operating data of the cold start-up. A total of 164 original association rules are generated using the proposed method and were analyzed by experts. The recommendations were made for 4 different cases that would improve the operational performance of the operators. [ABSTRACT FROM AUTHOR]

In view of uncertainty of comprehensive evaluation index of security risks investigation and govern ability of coal mine, a set pair analysis and evaluation model was established. The model determines evaluation index system from two aspects of personnel factors and govern factors, taking positive and negative, similarity and dissimilarity connection degree into account to obtain a comprehensive connection degree, so as to realize quantitative evaluation of security risks investigation and govern ability of coal mine. The result of case analysis shows that the proposed model can reasonably evaluate security risks investigation and govern ability of coal mine, and the result is in line with the actual situation.

Nuclear power plant operating data are characterized by a large variety, strong coupling, and low data value density. When using machine learning techniques for fault diagnosis and other related research, feature selection enables dimensionality reduction while maintaining the physical meaning of the original features, thus improving the computational efficiency and generalization ability of the learning model. In this paper, a correlation-based feature selection algorithm is developed to implement feature selection of nuclear power plant operating data. The proposed algorithm is verified by experiments and compared with traditional correlation-based feature selection algorithms. The experiments and comparison results show that the proposed algorithm is effective in realizing the dimensionality reduction of nuclear power plant operating data. [ABSTRACT FROM AUTHOR]

Multipartite secret sharing schemes are those that have multipartite access structures. The set of the participants in those schemes is divided into several parts, and all the participants in the same part play the equivalent role. One type of such access structure is the compartmented access structure, and the other is the hierarchical access structure. We propose an efficient compartmented multisecret sharing scheme based on the linear homogeneous recurrence (LHR) relations. In the construction phase, the shared secrets are hidden in some terms of the linear homogeneous recurrence sequence. In the recovery phase, the shared secrets are obtained by solving those terms in which the shared secrets are hidden. When the global threshold is t , our scheme can reduce the computational complexity of the compartmented secret sharing schemes from the exponential time to polynomial time. The security of the proposed scheme is based on Shamir's threshold scheme, i.e., our scheme is perfect and ideal. Moreover, it is efficient to share the multisecret and to change the shared secrets in the proposed scheme. [ABSTRACT FROM AUTHOR]

Taking different parts of Tan mutton in Ningxia as samples, the rheological properties of Tan mutton at 0, 2, 4, and 8 days were studied by rotational rheometer. The stress relaxation under static state and the dynamic oscillation rheological properties in flow state was examined. The dynamic storage modulus, loss modulus, and complex viscosity with angular frequency were measured. The microstructure of Tan sheep was observed by field emission scanning electron microscope (FESEM) to elucidate the changes of surface microstructure of muscle fibers. The results showed that the Tan mutton was a non‐Newtonian fluid and exhibits pseudoplastic behavior. The apparent viscosity decreased with the increase of shear rate. The longissimus dorsi muscle was stored in 2, 4, 6, and 8 days. The Ostwald‐de Waele model had a coefficient of fit of 0.9245, 0.986, 0.992, 0.986, and the Ostwald‐de Waele model of the hind legmuscles at 2, 4, 6, and 8 days had a coefficient of fit of 0.744, 0.911, 0.346, and 0.604. The model fitting effect of the long muscle was better than that of the hind leg muscle, which indicated that the flow effect of the longissimus dorsi muscle was better than that of the hind leg muscle during processing. Overall, the Ostwald de Waele model could better describe the flow properties of meat emulsions, which was better than the Herschel Bulkley model. Practical applications: In this study, we have demonstrated that rheological property of Tan mutton was changed with the extension of time. This study can provide theoretical guidance for the improvement of meat deep processing technology. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the correlation among serum biochemical indices, slaughter traits, texture characteristics and water-holding capacity in Tan sheep. Eighty Tan sheep aged 4–6 months were selected. Blood samples were collected from live animals to analyse serum biochemical indices. The slaughter traits, texture characteristics and water-holding capacity of meat were assessed after slaughter. There were highly significant correlations (p<.01) and high linear regression R values among serum biochemical indices, slaughter traits, meat texture characteristics and water-holding capacity in Tan sheep. Therefore, this study has demonstrated that the meat qualities of Tan mutton may be evaluated by the serum biochemical indices of live Tan sheep. This study was conducted to determine the correlation among serum biochemical indices, slaughter traits, texture characteristics and water-holding capacity in Tan sheep. This study has demonstrated that meat qualities of Tan mutton may be assessed by the serum biochemical indices of live Tan sheep. It is necessary to determine slaughter traits, meat texture characteristics and water-holding capacity of meat, which are major indicators for assessing meat and meat products by consumers. [ABSTRACT FROM AUTHOR]

Firstly, we will show the following extension of the results on powers of -hyponormal and -hyponormal operators: let and be positive integers, if is -hyponormal for , then: (i) in case , and hold, (ii) in case , and hold. Secondly, we will show an estimation on powers of -hyponormal operators for which implies the best possibility of our results. Lastly, we will show a parallel estimation on powers of -hyponormal operators as follows: let , then the following hold for each positive integer and : (i) there exists a log-hyponormal operator such that , (ii) there exists a -hyponormal operator such that .

In this paper, the MOFs-derived carbonaceous ZnO and RGO (carbonaceous ZnO/RGO) composites have been prepared by the wet chemical method and carbonization process. The as-prepared products are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), Raman spectra, thermogravimetric (TG) analysis and X-ray photoelectron spectroscopy (XPS). The electromagnetic parameters of carbonaceous ZnO/RGO composites are investigated by the vector network analyzer. The results exhibit carbonaceous ZnO/RGO composites have a maximum absorption of − 3 7. 1 2 dB at 6 GHz with thickness of 3.5 mm and the effective absorption (below − 1 0 dB) bandwidth is up to 1.92 GHz (from 5.28 to 7.2 GHz). Thus, the carbonaceous ZnO/RGO composites have great potential in the field of electromagnetic wave absorption. A simple wet chemical method has been employed to synthesize MOF and GO composites, and the MOF-derived carbonaceous ZnO and RGO are prepared by simple heat treatments of MOFs precursors and GO under inert gas condition. The carbonaceous ZnO/RGO composites also exhibit enhanced microwave absorption properties. [ABSTRACT FROM AUTHOR]

Composites of porous Co0.5Zn0.5 zeolitic imidazolate framework (CZ-ZIF)-derived binary Co/ZnO with reduced graphene oxide (RGO) have been prepared by a wet chemical method and carbonization process. CZ-ZIF-derived Co/ZnO microframes with diameter of about 250 nm were dispersed onto the surface of RGO nanosheets. The impedance matching of the composite could be adjusted by controlling the weight ratio of RGO to Co/ZnO microframes. Due to its porous structure, excellent impedance matching, and dielectric loss characteristics, the Co/ZnO/RGO composite exhibited maximum reflection loss (RL) of − 52.2 dB at 10.96 GHz. Coatings with thickness of 2.0 mm to 4.0 mm showed bandwidth of 5.6 GHz (from 8.72 GHz to 14.32 GHz) for RL of − 10 dB (90% absorption). Additionally, the amount of composite added into paraffin matrix was only 8 wt.%, less than for most electromagnetic (EM) wave absorbers in previous reports. Therefore, such Co/ZnO/RGO composites may be promising candidate EM wave absorbing materials. [ABSTRACT FROM AUTHOR]

The role of the counter electrode (CE) in dye-sensitized solar cell (DSSC) is to collect electrons from the external circuit and reduce I to I in the electrolyte. In this paper, the perovskite-phase LaSrCoO (LSCO) nanoparticles were synthesized through a sol-gel method and used as the CE for DSSC. The cell showed a power conversion efficiency ( PCE) of 3.24 %. To further improve the PCE of CE of the LSCO nanoparticles, the nanocomposites of the LSCO nanoparticles with reduced graphene oxide (LSCO@RGO) have been prepared via a simply physical mixing method and served as the efficient CE for DSSC. The LSCO@RGO nanocomposites exhibit excellent electrocatalytic performance for reduction of triiodide, owing to the positive synergetic effect between LSCO nanoparticles and RGO sheets. As a consequence, the DSSC with the LSCO@RGO nanocomposites CE yielded a PCE of 6.32 %, which is observably higher than that of using pristine LSCO CE (3.24 %) or RGO CE (4.54 %) alone, and up to 88 % of the Pt CE (7.18 %). [ABSTRACT FROM AUTHOR]

It is well-known that hyponormal operators have many interesting properties, for example, if the restriction $$T|_{{\mathcal {M}}}$$ of the hyponormal operator T on its nontrivial closed invariant subspace $${\mathcal {M}}$$ is normal, then $${\mathcal {M}}$$ reduces T. In order to discuss the reducibility of invariant subspaces of an operator, four properties of invariant subspaces ( $$R_{i}, i=1,\ldots ,4$$ ) are introduced. Among others, it is proved that, for a k-quasi- A( n) operator T, if the restriction $$T|_{{\mathcal {M}}}$$ is normal and injective, then $${\mathcal {M}}$$ reduces T, thus the function $$\sigma :T\longmapsto \sigma (T)$$ is continuous on the class of k-quasiclass- A( n) operators. Some examples related to class A( n) and n-paranormal operator are given which imply that the inclusion relations are strict. [ABSTRACT FROM AUTHOR]

Abstract: Let be a unital -algebra, the algebra of all bounded linear operators on a Hilbert space , and the set of all positive linear maps from to . The well-known Kadison’s inequality on unital positive linear maps is said that, if and is unital, then for each Hermitian . This paper is to consider the extensions of Kadison’s inequality, some inequalities for unital are obtained which generalize Furuta’s result, and a complement to a result of Bourin and Ricard is provided. [Copyright &y& Elsevier]

Let n be a positive integer, an operator T belongs to class A( n) if $$|T^{1+n}|^{2/(1+n)} \geq |T|^{2}$$ , which is a generalization of class A and a subclass of n-paranormal operators, i.e., $${\parallel}T^{1+n}x{\parallel}^{1/(1+n)} \geq {\parallel}Tx{\parallel}$$ for unit vector x. It is showed that if T is a class A( n) or n-paranormal operator, then the spectral mapping theorem on Weyl spectrum of T holds. If T belongs to class A( n), then the nonzero points of its point spectrum and joint point spectrum are identical, the nonzero points of its approximate point spectrum and joint approximate point spectrum are identical. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the effectiveness of Lycium barbarum polysaccharide (LBP) on lipid oxidation and protein degradation in Tan sheep meatballs during the frozen period. The meatballs were treated with LBP at 0.01%, 0.02%, and 0.03% and stored at -18±1°C for 0, 3, 6, 9, and 12 weeks. The effects of LBP treatment were investigated using the contents of total volatile basic nitrogen (TVB-N), texture profile (TP), thiobarbituric acid reactive substances (TBARS), colour, and pH values, compared with 0.02% butylated hydroxytoluene treatment and the blank control. The results showed that LBP treatment significantly decreased TBARS content compared with the control, which confirmed LBP to be a highly effective component in preventing lipid oxidation of Tan sheep meatballs during frozen storage, and protein degradation in Tan sheep meatballs had a significant inhibition effect because of TVB-N value reduction. In addition, the colour, TP and pH values of meatballs treated with LBP were improved dramatically. To further determine the quality changes of the blank control and all treated groups during storage, the comprehensive score evaluation equation based on principal component analysis was obtained: Y=0.51632Y 1 +0.29589Y 2 (cumulative contribution rate=81.221%), and the 0.02% LBP-treated group had a higher comprehensive score than the other groups, and the quality of LBP-treated meatballs was better as well. In summary, LBP may reduce or inhibit lipid oxidation and protein degradation, and enhance overall quality and shelf-life in prepared meat products., Competing Interests: The authors declare no potential conflicts of interest., (© Korean Society for Food Science of Animal Resources.)

Invasion and metastasis are major factors in the poor prognosis of pancreatic cancer, which remains one of the most aggressive and lethal diseases worldwide. α-mangostin, a major xanthone compound identified in the pericarp of mangosteen ( Garcinia mangostana , Linn; GML), possesses unique biological activities, including antioxidant, antitumor and anti-inflammatory effects. Whether α-mangostin is able to inhibit the invasive ability of pancreatic cancer cells has not been elucidated. In the present study, α-mangostin was shown to inhibit the invasive ability of the pancreatic cancer cell lines MIAPaCa-2 and BxPC-3. The results showed that α-mangostin inhibited the growth of the pancreatic cancer cells in a dose- and time-dependent manner. At concentrations of <5 μ M, α-mangostin had no significant effects on cytotoxicity, but significantly inhibited the invasion and migration of pancreatic cancer cells and the expression of matrix metalloproteinase (MMP)-2 and MMP-9, while increasing the expression of E-cadherin. The present data also showed that α-mangostin exerted an inhibitory effect on the phosphorylation of extracellular-signal-regulated kinase (ERK). Furthermore, the reduction of ERK phosphorylation by small interfering RNA (siRNA) potentiated the effect of α-mangostin. Taken together, the data suggest that α-mangostin inhibited the invasion and metastasis of pancreatic cancer cells by reducing MMP-2 and MMP-9 expression, increasing E-cadherin expression and suppressing the ERK signaling pathway. The present study suggests that α-mangostin may be a promising agent against pancreatic cancer.