Wyniki wyszukiwania - Biblioteka Nauki

1

Mechanical Spectroscopy: Some Applications on Structural Changes and Relaxation Dynamics in Soft Matter

100%

Wu Q. , Liu C.

Archives of Metallurgy and Materials

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2015

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tom Vol. 60, iss. 3A

2077--2083

EN

The general trend in soft matter is to study systems of increasing complexity covering a wide range in time and frequency. Mechanical spectroscopy is a powerful tool for understanding the structure and relaxation dynamics of these materials over a large temperature range and frequency scale. In this work, we collect a few recent applications using low-frequency mechanical spectroscopy for elucidating the structural changes and relaxation dynamics in soft matter, largely based on the author’s group. We illustrate the potential of mechanical spectroscopy with three kinds of soft materials: colloids, polymers and granular systems. Examples include structural changes in colloids, segmental relaxations in amorphous polymers, and resonant dissipation of grain chains in three-dimensional media. The present work shows that mechanical spectroscopy has been applied as a necessary and complementary tool to study the dynamics of such complex systems.

PL

Ogólnym trendem w miękkiej materii jest, aby badać układy o rosnącej złożoności, obejmującej szeroki zakres czasu i częstotliwości. Spektroskopia mechaniczna jest potężnym narzędziem dla zrozumienia struktury i dynamiki relaksacji tych materiałów w szerokim zakresie temperatury i skali częstotliwości. W niniejszej pracy, zebraliśmy kilka ostatnich zastosowań spektroskopii mechanicznej niskiej częstotliwości do poznania zmian strukturalnych i dynamiki relaksacji w miękkiej materii, w dużej mierze opartych na grupie autorów. Opisujemy potencjał spektroskopii mechanicznej w przypadku trzech rodzajów materiałów miękkich: koloidów, polimerów i układów ziarnistych. Przykłady obejmują zmiany strukturalne w koloidach, segmentowe relaksacje amorficznych polimerów, i rezonansowe rozpraszanie łańcuchów ziaren w mediach trójwymiarowych. Niniejsza praca pokazuje, że spektroskopię mechaniczną zastosowano jako niezbędne i uzupełniające narzędzie do badania dynamiki takich systemów złożonych.

2

Robust distributed privacy-preserving secure aggregation in vehicular communication

80%

Qin B. , Wu Q. , Domingo-Ferrer J. , Susilo W.

Control and Cybernetics

|

2012

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tom Vol. 41, no. 2

277-296

EN

Vehicular ad hoc networks (VANETs), formed by computers embedded in vehicles and the traffic infrastructure, are expected to develop in the near future to improve traffic safety and efficiency. To this end, VANETs should be designed to be resistant against various abuses and attacks. In this paper, we first review the existing proposals to provide security, privacy, and data aggregation in vehicle-to-vehicle communication. We then address the fundamental issue of achieving these conflicting properties in a unified solution, having observed that separate efforts cannot fulfill the VANET design objectives. A set of new mechanisms are suggested for efficiently managing identities and securely compressing cryptographic witnesses, which are among the major obstacles to the deployment of strong security mechanisms in VANETs. Finally, we employ the standard threshold cryptographic technology to improve the basic protocol with robustness.

3

An efficient provably secure certificateless aggregate signature applicable to mobile computation

80%

Xiong H. , Wu Q. , Chen Z.

Control and Cybernetics

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2012

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tom Vol. 41, no. 2

373-391

EN

An aggregate signature scheme allows a public algorithm to aggregate n signatures on n distinct messages from n signers into a single signature. By validating the single resulting signature, one can be convinced that the messages have been endorsed by all the signers. Certificateless aggregate signatures allow the signers to authenticate messages without suffering from the complex certificate management in the traditional public key cryptography or the key escrow problem in identity-based cryptography. In this paper, we present a new efficient certificateless aggregate signature scheme. Compared with up-to-date certificateless aggregate signatures, our scheme is equipped with a number of attracting features: (1) it is shown to be secure under the standard computational Diffie-Hellman assumption in the random oracle model; (2) the security is proven in the strongest security model so far; (3) the signers do not need to be synchronized; and (4) its performance is comparable to the most efficient up-to-date schemes. These features are desirable in a mobile networking and computing environment where the storage/ computation capacity of the end devices are limited, and due to the wireless connection and distributed feature, the computing devices are easy to be attacked and hard to be synchronized.

4

Analyzing photosynthetic activity and growth of Soanum lycopersicum seedlings exposed to different light qualities

80%

Wu Q. , Su N. , Shen W. , Cui J.

Acta Physiologiae Plantarum

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2014

|

tom 36

|

nr 06

EN

To investigate how light quality influences tomato (Solanum lycopersicum L) seedlings, we examined changes in plant growth, chloroplast ultrastructure, photosynthetic parameters and some photosynthesis-related genes expression levels. For this, tomato plants were grown under different light qualities with the same photosynthetic photon flux density: red (R), blue (B), yellow (Y), green (G) and white (W) lights. Our results revealed that, compared with plants grown under W light, the growth of plants grown under monochromatic lights was inhibited with the growth reduction being more significant in the plants grown under Y and G lights. However, the monochromatic lights had their own effects on the growth and photosynthetic function of tomato seedlings. The plant height was reduced under blue light, but expression of rbcS, rbcL, psbA, psbB genes was up-regulated, and the ΦPSII and electron transport rate (ETR) values were enhanced. More starch grains were accumulated in chloroplasts. The root elongation, net photosynthetic rate (Pn), NPQ and rbcS and psbA genes expression were promoted under red light. Yellow light- and green light-illuminated plants grew badly with their lower Rubisco content and Pn value observed, and less starch grains accumulated in chloroplast. However, less influence was noted of light quality on chloroplast structure. Compared with yellow light, the values of ΦPSII, ETR, qP and NPQ of plants exposed to green light were significantly increased, suggesting that green light was beneficial to both the development of photosynthetic apparatus to some extent.

5

Macro and structural effects of carbon tax in China based on the ECGE model

80%

Wu Q. , Li C. , Zhang H. , Tian J.

Polish Journal of Environmental Studies

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2019

|

tom 28

|

nr 4

EN

Rapid economic development has brought great pressure to China. Carbon tax could be an ideal economic tool to cope with the environmental pressure. The implementation of carbon tax will exert an influence on the national and sectoral economies as well as reduction. However, few researchers have focused on the carbon tax effect at the sectoral level. Based on SAM 2012, this study develops an ECGE model consisting of the environment module. Then the macro and structural effects of carbon tax are simulated at tax rates of 10-100 yuan/t CO2 in China. Simulation results show that compared with the baseline: 1) Carbon tax has a mild strike on the GDP of China and is effective at reducing emissions. Furthermore, we found that a carbon tax rate of 70 yuan/t CO2 may be an appropriate rate to achieve the Chinese reduction target of carbon intensity in the year 2020. 2) Carbon tax induces an output shrinkage in energy or high-energy-consuming industries by 0.95-7.65%, while there is a slight increase in low-energy-consuming industries. The mining and washing of coal industry (coal) experiences the largest decrease in CO2 emissions and the light industry (lindus) experiences the sharpest decline in carbon intensity.

6

Orthogonal Evolutionary Algorithm and its Application in Circuit Design

80%

Yan X. , Wu Q. , Liu H.

Przegląd Elektrotechniczny

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2012

|

tom R. 88, nr 5b

7-10

EN

During the space electronic system in carries out the exploratory mission in the deep space, it maybe faced with kinds of violent natural environment, to electric circuit's performance, the volume, the weight and the stability proposed a higher request, the traditional circuit design method already more and more with difficulty satisfied this kind of request. In this paper, proposed a new orthogonal evolutionary algorithm which uses in the electronic system circuit optimization design and through the experiment proved, the algorithm obtains the circuit structure to surpass the tradition circuit design method. For the case studies, this means has proved to be efficient and the experiment results show that the new means have got the better results.

PL

W artykule zaproponowano nowy ortogonalny algorytm ewolucyjny pozwalający na optymalizację projektowania systemów elektronicznych. Eksperymenty dowiodły że alorytm jest znacznie skuteczniejszy od tradycyjnych metod projektowania.

7

Ship domain model for multi-ship collision avoidance decision-making with COLREGs based on artificial potential field

80%

Wang T. F. , Yan X. P. , Wang Y. , Wu Q.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2017

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tom Vol. 11, no. 1

85--92

EN

A multi-ship collision avoidance decision-making and path planning formulation is studied in a distributed way. This paper proposes a complete set of solutions for multi-ship collision avoidance in intelligent navigation, by using a top-to-bottom organization to structure the system. The system is designed with two layers: the collision avoidance decision-making and the path planning. Under the general requirements of the International Regulations for Preventing Collisions at Sea (COLREGs), the performance of distributed path planning decision-making for anti-collision is analyzed for both give-way and stand-on ships situations, including the emergency actions taken by the stand-on ship in case of the give-way ship’s fault of collision avoidance measures. The Artificial Potential Field method(APF) is used for the path planning in details. The developed APF method combined with the model of ship domain takes the target ships’ speed and course in-to account, so that it can judge the moving characteristics of obstacles more accurately. Simulation results indicate that the system proposed can work effectiveness.

8

Experimental and optimization design of offshore drilling seal

80%

Zhang Y. , Zhang X. , Chang X. , Wu Q.

Polish Maritime Research

|

2017

|

tom 24

|

nr Special Issue S3

EN

Three-cone bit is the key equipment in the exploration of the oil in offshore drilling and exploration, the bearing system and the seal system are the critical components for the bit. Especially in the offshore drilling environment, the seal design need to be carefully considered. A multi-objective optimization design including orthogonal design method and F-test with finite element analysis for a three-cone bit seal is proposed. Firstly, the calculation method of optimization targets are given, including the minimization of maximum contact pressure and leakage rate analyzed by ANSYS and MATLAB respectively, to maximize seal life and reliability. Then, an orthogonal experiment approach is used to investigate the effects of the eleven parameters on the seal performance, and the influence degrees of the seal factors on the optimization targets have been confirmed by F-test, and the reasonable factors can be determined by the trend of the targets. Finally, in order to validate the analysis results, a new seal was designed and tested on a seal tester compared to the previous seal. In this test, the seal maximum interface temperature that reflects the position of maximum contact pressure can be obtained by using three high precision thermocouples. Both the experiment results and the numerical analyses proved that the maximum contact pressure and leakage rate of the improved seal have been reduced compared to the previous

9

A Multi-Agent Based Method for Service Restoration in Shipboard Power System

80%

Li H. L. , Sun H. , Wen J. , Wu Q.

Przegląd Elektrotechniczny

|

2012

|

tom R. 88, nr 6

354-359

EN

The shipboard power system (SPS) supplies energy to electric loads on ships. If the power supply of SPS is interrupted by a fault, it is important to restore the power system as soon as possible. Many approaches have been taken on the service restoration of SPS, but most of them use a centralized method and cannot meet the Navy's needs for fight-through survivability and high reliability. This paper improves the mathematical programming method proposed in the early literature and presents a multi-agent system framework performing system restoration for Navy ship. In the MAS, all agents have the ability to collect information, process data and make reasonable decisions independently according to different environment. The MAS is implemented based on Java Agent development framework (JADE). The simulation results of typical SPS service restoration cases demonstrated the feasibility and the advantages of the proposed MAS.

PL

W artykule zaproponowano ulepszoną metodę wykorzystująca system typu multi agent. Każdy z agentów ma możliwość zbierania informacji, przetwarzania danych i podejmowania decyzji w różnych okolicznościach.

10

New Construction of Short Hierarchical ID-Based Signature in the Standard Model

80%

Zhang L. , Hu Y. , Wu Q.

Fundamenta Informaticae

|

2009

|

tom Vol. 90, nr 1-2

191-201

EN

In this paper, a new construction of hierarchical ID-Based signature (HIBS) scheme is proposed. The new scheme has some advantages over the available schemes: the private keys size shrinks as the identity depth increases and the signature size is a constant as it consists of three group elements. Furthermore, under the h-CDH assumption, our scheme is provably secure in the standard model. This assumption is more natural than many of the hardness assumptions recently introduced to HIBS in the standard model.

11

Outdoor radon concentration in China

80%

Wu Q. , Pan Z. , Liu S. , Wang C.

Nukleonika

|

2016

|

tom Vol. 61, No. 3

373--378

EN

A nationwide survey was conducted in 2014 to investigate environmental outdoor radon level in 33 provincial cities across China. The radon detector used was a passive-type solid-state nuclear track detector, CR-39. Measurements were conducted under the same condition following the quality control programme. Outdoor radon concentrations in China ranged from 3 to 30.0 Bq·m−3. The annual arithmetic and geometric mean radon concentration were 14 and 13.2 Bq·m−3, respectively. The radon concentrations in the locations near or along coastline were lower than the average value, while those located in the inland area were higher. As a whole, the result showed no big difference from the data measured during the period 1983–1998. It demonstrated that the outdoor radon concentration level in China has not been changing remarkably for 20 years.

12

An empirical study on the shadow price of carbon dioxide emissions in China’s industry

80%

Wu Q. , Zhang H. , Zhang R. , Li C.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 2

13

Experimental and optimization design of offshore drilling seal

80%

Zhang Y. , Zhang X. , Chang X. , Wu Q.

Polish Maritime Research

|

2017

|

tom S 3

72--78

EN

Three-cone bit is the key equipment in the exploration of the oil in offshore drilling and exploration, the bearing system and the seal system are the critical components for the bit. Especially in the offshore drilling environment, the seal design need to be carefully considered. A multi-objective optimization design including orthogonal design method and F-test with finite element analysis for a three-cone bit seal is proposed. Firstly, the calculation method of optimization targets are given, including the minimization of maximum contact pressure and leakage rate analyzed by ANSYS and MATLAB respectively, to maximize seal life and reliability. Then, an orthogonal experiment approach is used to investigate the effects of the eleven parameters on the seal performance, and the influence degrees of the seal factors on the optimization targets have been confirmed by F-test, and the reasonable factors can be determined by the trend of the targets. Finally, in order to validate the analysis results, a new seal was designed and tested on a seal tester compared to the previous seal. In this test, the seal maximum interface temperature that reflects the position of maximum contact pressure can be obtained by using three high precision thermocouples. Both the experiment results and the numerical analyses proved that the maximum contact pressure and leakage rate of the improved seal have been reduced compared to the previous.

14

Spatial characteristics and influencing factors of carbon emissions from energy consumption in China’s transport sector: an empirical analysis based on provincial panel data

80%

Peng Z. , Wu Q. , Li M.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 1

15

Efficient Dynamic Data Encryption Algorithm for Mobile Ad Hoc Network

80%

Zhang L. , Wu Q. , Hu Y.

Przegląd Elektrotechniczny

|

2012

|

tom R. 88, nr 9b

42-46

EN

Two proper threshold broadcast encryption schemes are proposed for the mobile ad hoc network. The initial scheme achieves constant size private keys and O(n-t)-size ciphertexts. Under n+1-Decision Bilinear Diffie-Hellman Exponent (n+1-BDHE) assumption, it is provable security in the selective-identity model. Based on the dual system encryption, we propose our main construction. It also has constant size private keys and O(nt)- size ciphertexts. But it achieves full security under the static assumptions which are more natural than them in the existing schemes.

PL

W artykule zaprezentowano dwie metody szyfrowania danych w mobilnych sieciach Ad Hoc.

16

Temporal-spatial pattern and influencing factors of China’s province-level transport sector carbon emissions efficiency

80%

Peng Z. , Wu Q. , Wang D. , Li M.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 1

17

Theoretical Determinations of Ionization Potential and Electron Affinity of Gaseous alfa-Alanine

71%

Lu J. , Zhu S. , Zhou Z. , Wu Q. , Zhao G.

Polish Journal of Chemistry

|

2006

|

tom Vol. 80, nr 3

471-481

EN

Adiabatic (vertical) ionization potential (IP) and valence electron affinity (EA) of gaseous alfa-alanine have been determined by density functional theory (B3LYP), ab initio Hartree-Fock (HF) calculations and ab initio third order algebraic diagrammatic construction [ADC(3)] Green function method with the 6-311++G** and 6-311G** basis sets, respectively. Eighteen possible conformers of alfa-alanine and its charged states have been optimized, employing density functional theory (B3LYP) with 6-311++G** and 6-311G** basis sets, respectively. In the gas phase, the IPs of all alfa-alanine calculated have positive values and all the EAs are negative, except for VEA2 (+0.555 eV) of 6A, which indicates that all anions except for 6A- are unstable with respect to electron autodetachment vertically and adiabatically. All kinds of chemical quantities, associated with the IP and EA, such as electronegativity, chemical potential, chemical hardness, and chemical softness, have also been determined. Finally, we also report the infrared spectrum frequencies and vibrational modes for neutral states of alfa-alanine 1A, 2A, 3A, 5A and their optimized cationic and anionic states in seven highest frequency regions, and analyzed the relationship between the vibrational frequencies when receiving or donating an electron.

18

Effects of land use change of sloping farmland on characteristic of soil erosion resistance in typical karst mountainous areas of Southwestern China

71%

Li R. , Wu Q. , Zhang J. , Wen Y. , Li Q.

Polish Journal of Environmental Studies

|

2019

|

tom 28

|

nr 4

EN

With the implementation of ecological projects such as the Grain-for-Green Project, rocky desertification control and comprehensive control of soil and water loss for sloping farmland, ecological environment of karst mountainous areas in southwest China has been improved significantly, but soil and water loss of sloping farmland is still an important ecological and environmental problem in this region. In this paper we took a typical karst rocky desertification mountainous area, Jinlan Demonstration Area, as the study area located in Qianxi County, Guizhou Province. On the basis of a previous experimental demonstration of grass planting and afforestation on sloping farmland (planted in 2014), the sample plot method was used to obtain soil samples and soil shearing test piece in 2017, and soil shear strength and soil erodibility factor (K) were measured by direct shear method and hydrometer method in order to study the effect of sloping farmland converted to abandoned land, pastureland and agroforestry on soil erosion resistance. Results showed that the soil sheer strength was no obvious change and soil erodibility was no significant difference (P>0.05) in sloping farmland with the level of rocky desertification becoming more serious; soil sheer strength greatly increased after sloping farmland was abandoned, ultimate shear strength τ300 was increased by 65.5%, and K was significantly different (P<0.05) after 10 years; in the process of sloping farmland converted to pastureland, the soil ultimate shear strength τ300 was increased by 34.55% and K decreased significantly (P<0.05), which indicated that the effect of grass planting on improving soil erosion resistance of sloping farmland was obvious; in the process of sloping farmland converted to agroforestry, soil erosion resistance was also enhanced, soil shear strength was increased, and K was decreased (it did not reach the significant level, P>0.05). Based on the preliminary results of this paper, we think both grass (tree) planting and land abandonment could improve soil erosion resistance and reduce soil erosion risk, whichare feasible non-engineering measures for soil and water conservation in the karst area of southwestern China.

19

Transformational leadership in operational competitiveness improvement: a case study in Malaysian automotive industry

71%

Wu Q. , Shamsuddin A. , Tasmin R. , Takala J. , Liu Y.

Management and Production Engineering Review

|

2012

|

tom Vol. 3, No. 1

62-70

EN

The purpose of this paper is to analyze operational competitiveness by two core factors, i.e. manufacturing strategy and transformational leadership with technology level. In additional, CFI models in sense and respond (S&R) method are introduced to optimize strategic adjustments, which give supports in fast strategic decision-making process. The analysis results of case study show that leaders in automobile companies in Malaysia should deeply develop their leadership by inspirational motivation, intellectual stimulation and building trust and confidence etc. to improve operational competitiveness. Agile operations strategy should be utilized towards automobile enterprises in Malaysia in order to be competitive under dynamic and tightrope business situations.

20

Effects of exogenous Fibroblast Growth Factor-21 on characteristic parameters related to energy metabolism in dairy cows

61%

Chen Y. , Wu Q. , Gao Y. , Zhang H. , Dong Z. , Li R. , Xu C.

Medycyna Weterynaryjna

|

2019

|

tom 75

|

nr 12

EN

Negative energy balance (NEB) is a common pathological foundation of fatty liver and ketosis. Liver and fat tissue are the major organs of lipid metabolism, which is also a key metabolic pathway that regulates NEB development during the perinatal period. Fibroblast growth factor-21 (FGF-21) is a protein hormone that plays an important role in adipose lipid metabolism and liver gluconeogenesis. Our aim was to investigate the effects of exogenous FGF-21 on characteristic parameters related to energy balance in dairy cows. Ten non-pregnant, non-lactating Holstein-Friesian dairy cows were randomly allocated into two groups. The interventions were exogenous FGF-21 injection group received 1 ug/kg BW (body weight) of recombinant bovine FGF-21 by intravenous injection, and control group received physiological saline injections by intravenous injection. In comparison to saline injections, intravenous injections of FGF-21 either increased or tended to increase concentrations of FGF-21 (p < 0.05), BHBA (p < 0.05), adiponectin, leptin and HDL-C. FGF-21 injections decreased or tended to decrease concentrations of insulin, glucose, glucagon (p < 0.05), ALT/GPT (p < 0.05), AST/GOT (p < 0.05), urate, creatinine (p < 0.05), BUN, triglyceride (p < 0.05), T-CHO and LDL-C (p < 0.05). The results indicate that FGF-21 has only negative effects on the metabolites and metabolic hormones related to NEB in serum of dairy cows, but it has more beneficial effects on prominent adipokines, liver function index, renal function index, lipoprotein profiles related to the pathological changes that occurred in NEB.