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1

Research and application of rule updating mining algorithm for marine water quality monitoring data

Sun Q, Zhang J., Xu X

Polish Maritime Research

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2018

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S 3

136--140

EN

This paper studies the characteristics of marine water quality monitoring data monitored by photoelectric sensor network, mines the potential information from the massive data. on account of the continuous accumulation of monitoring data, this paper focuses on the study of database with numerical attribute and proposes a rule updating algorithm for solving the rule maintenance issues caused by changes in the database. according to the rule, the algorithm forms a new database from part of the original data and the new data, and searches the new database by random search, thus can avoid creating a large number of redundant rules and can quickly mine effective rules at the same time. experimental results show that this method not only can avoid mining in the whole original massive data, but also can improve work efficiency, and can quickly and effectively find new data and find useful rules in the data with high practicability.

2

4-Amino-3-hydrazino-1,2,4-triazole: a Precursor for the Preparation of Divalent Energetic Materials

Lin Q., Wang P., Sun Q., Lu M.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

18--29

EN

4-Amino-3-hydrazino-1,2,4-triazole (AHT) was developed as a divalent cation. The multivalent structure can be used to increase the number of nitrogen-rich heterocycles, thereby increasing the heat of formation and improving the detonation performance. Herein we report on a family of divalent energetic salts, which exhibit excellent properties, viz. acceptable density, good detonation performance, and desirable thermal and impact stabilities. The structural features of the salts were further determined by single-crystal X-ray diffraction. In addition, the detonation properties calculated for these energetic salts identified them as competitively energetic compounds.

3

Fatigue Behavior and Mechanism of FV520B-I Owing to the Effect of Loading Frequency on the Fatigue Property in HCF and VHCF Regime

Wang J., Zhang Y., Shi B., Zhao Q., Sun Q., Zhang Z., Lu H.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

347--357

EN

Fatigue property of FV520B-I is affected by the ultrahigh loading frequency significantly, and the ultrasonic fatigue experimental data can’t be employed directly to analyze the fatigue failure in the actual remanufacturing engineering. However few theories about the effect of loading frequency on the fatigue property of FV520B-I has ever been proposed. In this paper, both ultrasonic experiment and conventional experiment are conducted out to obtain the fatigue data. The effect of loading frequency on the fatigue data distribution is discussed firstly, its fatigue limit declines with the increase of the loading frequency. Then the fracture surface observations are captured, the fatigue property and fatigue behavior mechanism of FV520B-I is examined by analyzing the fracture surface features, crack initiation and failure observations. A new material frequency correction factor is proposed and introduced to eliminate the influence of the loading frequency on the FV520B-I fatigue property. FV520B-I empirical fatigue life conversion model and fatigue strength conversion model are established with comprehensive use of a fitting algorithm based on the combination of experimental data and classic formula. A clear understand of the effect of loading frequency on the fatigue property of FV520B-I is novel and has an important significance in guaranteeing the accuracy of the actual fatigue analysis of FV520B-I in the remanufacturing engineering.

4

Spanning trees with a bounded number of leaves

Cai J., Flandrin E., Li H., Sun Q.

Opuscula Mathematica

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2017

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Vol. 37, no. 4

501--508

EN

n 1998, H. Broersma and H. Tuinstra proved that: Given a connected graph G with n ≥ 3 vertices, if d(u) + d(y) ≥n — k + 1 for all non-adjacent vertices u and v of G (k ≥ 1), then G has a spanning tree with at most k leaves. In this paper, we generalize this result by using implicit degree sum condition of t (2≤ t ≤k) independent vertices and we prove what follows: Let G be a connected graph on n ≥ 3 vertices and k ≥ 2 be an integer. If the implicit degree sum of any t independent vertices is at least [formula] for (k≥ t ≥ 2), then G has a spanning tree with at most k leaves.

5

Reliability analysis for multi-state system based on triangular fuzzy variety subset bayesian networks

He Q., Zha Y., Zhang R., Sun Q., Liu T.

Eksploatacja i Niezawodność

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2017

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Vol. 19, no. 2

158--165

PL

W niniejszej pracy zaproponowano nową metodę analizy niezawodności systemów wielostanowych wykorzystującą sieci Bayesa (BN) oparte na rozmytych podzbiorach zmienności opisanych za pomocą trójkątnej funkcji przynależności. Metoda ta uwzględnia rozmyty charakter danych dotyczących uszkodzeń, wielostanowość systemu oraz zmienność prawdopodobieństwa wystąpienia uszkodzenia w czasie. BN, które znalazły zastosowanie w modelowaniu i metodach obliczeniowych, wykorzystuje się także do analizy niezawodności. W przedstawionych badaniach, analizę BN uzupełniono o elementy teorii zbiorów rozmytych wykorzystując do opisu prawdopodobieństwa wystąpienia uszkodzenia, podzbiory zmienności opisane przez trójkątną funkcję przynależności. Niepewność zależności logicznej pomiędzy awariami reprezentowanymi przez różne węzły sieci opisano za pomocą tabel rozmytego prawdopodobieństwa warunkowego. W pierwszej kolejności analizowano prawdopodobieństwo uszkodzenia każdego korzenia (węzła głównego) w funkcji czasu. Następnie, wyznaczono trójkątny rozmyty podzbiór zmienności, za pomocą którego opisano rozmyte prawdopodobieństwo uszkodzenia węzłów głównych. Podzbiór ten wykorzystano do analizy niezawodności systemu wielostanowego przy pomocy rozmytych BN. Artykuł kończy opis wypadku podczas ruchu wózka windy szybkobieżnej, który potwierdza skuteczność i możliwość praktycznego wykorzystania proponowanej metody. Wyniki pokazują, że proponowane podejście może skutecznie rozwiązywać na wczesnym etapie problemy związane z niepewnością informacji oraz wielostanowością systemu.

EN

In this paper, a novel reliability analysis method for multi-state system is proposed on the basis of triangular fuzzy variety subset Bayesian network (BN). The method considers fuzziness, multi-state, and variety of failure probability over time. With advantages in modeling and computation, the BN is utilized for reliability analysis. Fuzzy set theory is introduced into the BN analysis by using triangular fuzzy variety subset to describe failure probability. The uncertainty of fault logical relationship between different nodes is described through fuzzy conditional probability tables. As a function of time, the failure probability of each root node is analyzed first. Subsequently, the triangle fuzzy variety subset is established to describe the fuzzy failure probability of root nodes. This subset is applied to analyze the reliability of multi-state system fuzzy BN. Finally, a case study on the car free movement accident of flexible high-speed elevator lift system is used to demonstrate the effectiveness and practicality of the proposed method. Results show that the proposed approach could effectively address the problems on information uncertainty and multi-state in the early stage.

6

Deashing and desulphurization of fine oxidized coal by falcon concentrator and flotation

Zhu X., Tao Y., Sun Q., Man Z., Xian Y.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

634--646

EN

Flotation and enhanced gravity separation based on different separation principles were carried out to investigate the desulphurization and deashing efficiency of fine oxidized coal. Surface properties of fresh and oxidized coals were tested by XPS and results showed that the contents of hydrophobic functional groups decreased while the content of hydrophilic functional groups increased after oxidization. Floatability and density analysis results showed that the floatability of coal samples decreased sharply because of oxidation, however, density composition of coal sample only had slight changes. Separation results showed that yields of gravity concentrates outclassed that of flotation concentrates, meanwhile, ash contents and sulfur contents of gravity concentrates were far lower than that of flotation concentrates. Yields and ash contents increased with the collector dosage and achieved to be 17.83 and 26.94% respectively when the collector dosage was 1600 g•Mg-1. Yields and ash contents of gravity concentrates decreased with the centrifugal force and increased with the recoil water flow with similar sulfur content. Clean coal with yield of 53.86%, ash content of 9.81%, sulfur content of 1.47% and with a corresponding desulphurization efficiency of 44.53% was achieved at centrifugal force of 107 g and recoil water flow of 13.3 dm3•min-1. For fine oxidized coal, enhanced gravity separation has a significant advantage of the separation efficiency compared with flotation.

7

Lifetime Distribution and Associated Inference of Systems with Multiple Degradation Measurements Based on Gamma Processes

Pan Z., Feng J., Sun Q.

Eksploatacja i Niezawodność

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2016

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Vol. 18, no. 2

307--313

EN

With development of science and technology, many engineering systems take on high reliable characteristic and usually have complex structure and failure mechanisms, with their reliability being evaluated by multiple degradation measurements. In certain physical situations, the degradation of these performance characteristics would be always positive and strictly increasing. Therefore, the gamma process is usually considered as a degradation process due to its independent and non-negative increments properties. In this paper, we suppose that a system has multiple dependent performance characteristics and that their degradation can be modeled by gamma processes. For such a multivariate degradation involving three or more performance characteristics, we propose to use a multivariate Birnbaum-Saunders distribution and its marginal distributions to approximate the reliability function and give the corresponding lifetime distribution. And then, the inferential method for the model parameters is developed. Finally, for an illustration of the proposed model and method, a simulated example is discussed and some computational results are presented.

PL

Wraz z rozwojem nauki i techniki, powstaje coraz więcej systemów inżynieryjnych o wysokich parametrach niezawodnościowych, które zwykle charakteryzują się złożoną strukturą i złożonymi mechanizmami uszkodzeń. Ocena niezawodności w przypadku takich systemów wymaga pomiarów współwystępujących procesów degradacji . W pewnych sytuacjach fizycznych, degradacja właściwości użytkowych systemu będzie zawsze dodatnia oraz ściśle rosnąca. Proces degradacji jest zwykle procesem gamma, który charakteryzują niezależne i nieujemne przyrosty. W niniejszej pracy, założono, że system ma wiele zależnych charakterystyk pracy oraz że ich degradację można modelować procesem gamma. W przypadkach takiej wielowymiarowej degradacji obejmującej trzy lub więcej charakterystyk pracy zaproponowano zastosowanie rozkładu Birnbauma-Saundersa (uwzględniającego wiele zmiennych) oraz jego rozkładów brzegowych do aproksymacji funkcji niezawodności oraz określania odpowiadającego jej rozkładu czasu pracy. Opracowano metodę wnioskowania dla parametrów modelu. Wreszcie, dla zilustrowania proponowanego modelu oraz metody, omówiono przykład symulacyjny oraz przedstawiono niektóre wyniki obliczeniowe.

8

Cycle life prediction of Lithium-ion cells under complex temperature profiles

Liu T., Cheng L., Pan Z., Sun Q

Eksploatacja i Niezawodność

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2016

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Vol. 18, no. 1

25--31

EN

Nowadays, the extensive use of Lithium-ion cells requires an accurate life prediction model. Failure of Lithium-ion cells usually results from a gradual and irreversible capacity fading process. Experimental results show that this process is strongly affected by temperature. In engineering applications, researchers often use the regression-based approach to model the capacity fading process over cycles and then perform the cycle life prediction. However, because of neglecting temperature influences, this classic method may lead to significant prediction errors, especially when cells are subject to complex temperature profiles. In this paper, we extend the classic regression-based model by incorporating cell temperature as a predictor. Two effects of temperature on cell capacity are considered. One is the positive effect that high temperature lets a cell discharge more capacity in a cycle; The other is the negative effect that high temperature accelerates cell capacity fading. A cycle life test with six cells are conducted to valid the effectiveness of our method. Results show that the improved model is more suitable to capture the dynamics of cell capacity fading path under complex temperature profiles.

PL

Obecne szerokie zastosowanie ogniw litowo-jonowych wymaga stworzenia trafnego modelu prognozowania ich trwałości. Uszkodzenia ogniw litowo-jonowych zazwyczaj wynikają ze stopniowego i nieodwracalnego procesu utraty pojemności. Wyniki doświadczeń pokazują, że na ten proces silny wpływ wywiera temperatura. W zastosowaniach inżynieryjnych, naukowcy często wykorzystują podejście oparte na regresji do modelowania procesu utraty pojemności w poszczególnych cyklach by następnie dokonać prognozy trwałości w danym cyklu pracy. Jednakże, ta klasyczna metoda nie bierze po uwagę wpływu temperatury, co może prowadzić do znacznych błędów predykcji, w szczególności, gdy ogniwa pozostają pod wpływem złożonych profili temperaturowych. W prezentowanym artykule, rozszerzono klasyczny model oparty na regresji poprzez włączenie temperatury ogniwa jako czynnika prognostycznego. Przeanalizowano dwa rodzaje wpływu temperatury na pojemność ogniw. Z jednej strony, wysoka temperatura oddziałuje pozytywnie pozwalając ogniwu na uzyskanie większej pojemności w danym cyklu; z drugiej strony jest to wpływ negatywny, ponieważ wysoka temperatura przyspiesza utratę pojemności ogniwa. Przy użyciu sześciu ogniw, przeprowadzono badanie trwałości w danym cyklu pracy w celu potwierdzenia skuteczności naszej metody. Wyniki pokazują, że udoskonalony model pozwala lepiej uchwycić dynamikę ścieżki utraty pojemności ogniwa w warunkach złożonych profili temperaturowych.

9

Variations of Strength, Resistivity and Thermal Parameters of Clay after High Temperature Treatment

Sun Q., Zhang W., Zhang Y., Yang L.

Acta Geophysica

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2016

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Vol. 64, no. 6

2077--2091

EN

This paper reports the variations of strength, resistivity and thermal parameters of clay after high-temperature heating. Experiments were carried out to test the physical properties of clay heated at temperatures ranging from room temperature to 800°C in a furnace. The experiment results show that below 400°C the uniaxial compressive strength and resistivity change very little. However, above 400°C, both increase rapidly. At a temperature under 400°C, the thermal conductivity and specific heat capacity decrease significantly. The thermogravimetric analysis (TG) and differential scanning calorimeter (DSC) test indicate that a series of changes occur in kaolinite at temperatures from 400 to 600°C, which is considered the primary cause of the variation of physical and mechanical properties of clay under high temperatures.

10

Variation of Wave Velocity and Porosity of Sandstone after High Temperature Heating

Sun Q., Zhang W., Su T., Zhu S.

Acta Geophysica

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2016

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Vol. 64, no. 3

633--648

EN

This paper reports the variations of mass, porosity, and wave velocity of sandstone after high temperature heating. The range of temperature to which the sandstone specimens have been exposed is 25-850°C, in a heating furnace. It has been shown that below 300°C, porosity and wave velocity change very little. Above 300°C, there is a rapid increase in porosity, but the wave velocity decreases significantly. The results of thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC) and mercury intrusion porosimetry (MIP) suggest that a series of changes occurred between 400 and 600°C in sandstone could be responsible for the different patterns of variation in porosity and wave velocity

11

Permeability Evolution and Rock Brittle Failure

Sun Q., Xue L., Zhu S.

Acta Geophysica

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2015

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Vol. 63, no. 4

978--999

EN

This paper reports an experimental study of the evolution of permeability during rock brittle failure and a theoretical analysis of rock critical stress level. It is assumed that the rock is a strain-softening medium whose strength can be described by Weibull’s distribution. Based on the two-dimensional renormalization group theory, it is found that the stress level λ c (the ratio of the stress at the critical point to the peak stress) depends mainly on the homogeneity index or shape parameter m in the Weibull’s distribution for the rock. Experimental results show that the evolution of permeability is closely related to rock deformation stages: the permeability has a rapid increase with the growth of cracks and their surface areas (i.e., onset of fracture coalescence point), and reaches the maximum at rock failure. Both the experimental and analytical results show that this point of rapid increase in permeability on the permeabilitypressure curve corresponds to the critical point on the stress-strain curve; for rock compression, the stress at this point is approximately 80% of the peak strength. Thus, monitoring the evolution of permeability may provide a new means of identifying the critical point of rock brittle fracture.

12

Solid Oxide Electrolyzer Cell Modeling: A Review

Stempien J. P., Sun Q., Chan S. H.

Journal of Power Technologies

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2013

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Vol. 93, nr 4

216--246

EN

Solid Oxide Electrolyzer Cell (SOEC) is a very good candidate technology for securing sustainable development for the future. It allows CO2 to be recycled into usable fuels and has potential for hydrogen economy. In this work the authors focus on development of SOEC through modeling different aspects of the cell: from design of specific elements to final incorporation of electrolyzers in the global energy system and network. The publications reviewed span from the 1970s to the present day and cover a selection of most contributed works. The selected publications provide means for modeling the solid oxide electrolyzer cell in both steady and transient states. The scale of the models ranges from micro to macro and to global energy system levels. The thrust of this work is to summarize the current level of development in modeling the solid oxide electrolyzer cell and to highlight unresolved problems and provide pointers in terms of research gaps requiring closer attention by engineers and scientists.

13

Efficient method for extraction and isolation of shionone from Aster tataricus L. f. by supercritical fluid extraction and high-speed counter-current chromatography

Wang D, Bai A, Lin X., Fang L., Shu X., Shi X., Sun Q., Wang X.

Acta Chromatographica

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2012

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Vol. 24, no. 4

615--625

EN

Supercritical fluid extraction (SFE) was used to extract shionone from Aster tataricus L. f. The effect of various parameters, i.e., temperature, pressure and sample particle size on yield was investigated with an analytical-scale SFE system to find the optimal conditions. The process was then scaled up by 50 times with a preparative SFE system under the optimized conditions of temperature 40 °C, pressure 30 MPa, and a sample particle size of 40–60 mesh. Then preparative high-speed counter-current chromatography was successfully used for isolation and purification of shionone from the SFE extract with a two-phase solvent system composed of n-hexane-methanol (2:1, volume ratio). The separation produced a total of 75 mg of shionone from 500 mg of the crude extract in one step separation with the purity of 98.7%, respectively, as determined by high-performance liquid chromatography (HPLC) and 92% recovery. The structure of shionone was identified by electrospray ionization-mass spectrometry (ESI-MS), hydrogen-1 nuclear magnetic resonance (1H-NMR), and carbon-13 nuclear magnetic resonance (13C-NMR).

14

Synthesis of fundamental frequency contours for Standard Chinese based on superpositional and tone nucleus models

Hirose K., Sun Q., Minematsu N.

Archives of Acoustics

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2007

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Vol. 32, No. 1

41-50

EN

A method for generating sentence F0 contours of Standard Chinese speech is developed. It is based on superposing tone components on phrase components in logarithmic frequency. While tone components are language specific, phrase components are assumed to be more language universal. Taking this situation into account, the method treats two kinds of components differently. The tone components are generated by concatenating F0 patterns of tone nuclei, which are predicted by a corpus-based scheme, while the phrase components are generated by rules. Experiments on F0 contour generation were conducted using 100 news utterances by a female speaker. First experiments were conducted on the generation of tone components, with phrase components of the original utterances being used unchanged. The results showed that the method could generate F0 contours close to those of target speech. Speech synthesis was conducted by substituting original F0 contours to generated ones by TD-PSOLA. A high score 4.5 in 5-point scale was obtained on average as the result of listening experiments on the quality of synthetic speech. Second experiments were on the generated phrase components, with the tone components extracted from the original utterances. Although the synthetic speech with generated F0 contours sounded mostly natural, there were occasional "degraded sounds", because of mismatch between the phrase and the tone components. To cope with the mismatch, a two-step method was developed, where information of the phrase contours was used for the prediction of tone components. Validity on the method was shown through perceptual experiments on synthesized speech.