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Layout Optimizations of Operational Amplifiers in Deep Submicron

Jun Shi

International Journal of Electronics and Telecommunications | 2020 | vol. 66 | No 2 | 287-293 | DOI: 10.24425/ijet.2020.131876

Keywords Layout Optimization Deep Submicron (DSM) Operational Amplifier place-and-route

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Abstract

Operational amplifies (op amps) are an integral part of many analog and mixed-signal systems. Op amps with vastly different levels of complexity are used to realize functions ranging from DC bias generation to high-speed amplification or filtering. The design of op amps continues to pose a challenge as the supply voltage and transistor channel lengths scale down with each generation of CMOS technologies. The thesis deals with the analysis, design and layout optimization of CMOS op amps in deep Submicron (DSM) from a study case. Finally, layout optimizations of op amps will be given, in which propose optimization techniques to mitigate these DSM effects in the place-and-route stage of VLSI physical design.

Authors and Affiliations

Jun Shi

Review of Lattice Boltzmann Method Applied to Computational Aeroacoustics

Weidong Shao Jun Li

Archives of Acoustics | 2019 | vol. 44 | No 2 | 215-238 | DOI: 10.24425/aoa.2019.128486

Keywords lattice Boltzmann method computational aeroacoustics dispersion and dissipation perfectly matched layers discontinuous Galerkin method

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Abstract

This paper presents the research studies carried out on the application of lattice Boltzmann method (LBM) to computational aeroacoustics (CAA). The Navier-Stokes equation-based solver faces the difficulty of computational efficiency when it has to satisfy the high-order of accuracy and spectral resolution. LBM shows its capabilities in direct and indirect noise computations with superior space-time resolution. The combination of LBM with turbulence models also work very well for practical engineering machinery noise. The hybrid LBM decouples the discretization of physical space from the discretization of moment space, resulting in flexible mesh and adjustable time-marching. Moreover, new solving strategies and acoustic models are developed to further promote the application of LBM to CAA.

Authors and Affiliations

Weidong Shao

Jun Li

Short-term wind power combined prediction based on EWT-SMMKL methods

Jun Li Liancai Ma

Archives of Electrical Engineering | 2021 | vol. 70 | No 4 | 801-817 | DOI: 10.24425/aee.2021.138262

Keywords combined model empirical wavelet transform prediction soft margin multiple kernel learning wind power

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Abstract

Since wind power generation has strong randomness and is difficult to predict, a class of combined prediction methods based on empiricalwavelet transform(EWT) and soft margin multiple kernel learning (SMMKL) is proposed in this paper. As a new approach to build adaptive wavelets, the main idea is to extract the different modes of signals by designing an appropriate wavelet filter bank. The SMMKL method effectively avoids the disadvantage of the hard margin MKL method of selecting only a few base kernels and discarding other useful basis kernels when solving for the objective function. Firstly, the EWT method is used to decompose the time series data. Secondly, different SMMKL forecasting models are constructed for the sub-sequences formed by each mode component signal. The training processes of the forecasting model are respectively implemented by two different methods, i.e., the hinge loss soft margin MKL and the square hinge loss soft margin MKL. Simultaneously, the ultimate forecasting results can be obtained by the superposition of the corresponding forecasting model. In order to verify the effectiveness of the proposed method, it was applied to an actual wind speed data set from National Renewable Energy Laboratory (NREL) for short-term wind power single-step or multi-step time series indirectly forecasting. Compared with a radial basic function (RBF) kernelbased support vector machine (SVM), using SimpleMKL under the same condition, the experimental results show that the proposed EWT-SMMKL methods based on two different algorithms have higher forecasting accuracy, and the combined models show effectiveness.

Bibliography

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[2] Liu H.Q., Li W.J., Li Y.C., Ultra-short-term wind power prediction based on copula function and bivariate EMD decomposition algorithm, Archives of Electrical Engineering, vol. 69, no. 2, pp. 271–286 (2020), DOI: 10.24425/aee.2020.133025.
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[6] Zhang Y.G., Wang P.H., Zhang C.H., Lei S., Wind energy prediction with LS-SVM based on Lorenz perturbation, The Journal of Engineering, vol. 2017, no. 13, pp.1724–1727 (2017), DOI: 10.1049/joe.2017.0626.
[7] Duan J., Wang P., Ma W., Short-term wind power forecasting using the hybrid model of improved variational mode decomposition and Correntropy Long Short-term memory neural network, Energy, vol. 214, 118980 (2021), DOI: 10.1016/j.energy.2020.118980.
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Authors and Affiliations

Jun Li

1

Liancai Ma

1

Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China

The Variation of Precipitated Phase Investigated with the Usage of Nonlinear Ultrasonic Technique

Jun You Yunxin Wu Hai Gong

Archives of Acoustics | 2021 | vol. 46 | No 4 | 605-610 | DOI: 10.24425/aoa.2021.138153

Keywords nonlinear ultrasound Al-Cu precipitation 2219-T6 aluminum alloy precipitates phase

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Abstract

It is well known that nonlinear ultrasound is sensitive to some microstructural characteristics in material. This paper investigates the dependence of the nonlinear ultrasonic characteristic on Al-Cu precipitation in heat-treated 2219-T6 aluminum alloy specimens. The specimens were heat-treated at a constant temperature 155℃ for different exposure times up to 1800 min. The nonlinearity parameter and the changes of precipitates phase were measured for each of the artificially aged specimens. The experimental results show fluctuations in the fractional change in nonlinear parameter (Δβ/β0) and the changes of precipitated phase over the aging time, but with an interesting correlation between the fractional change in nonlinear parameter (Δβ/β0) and the change of precipitate phase over the aging time. Through the experimental data results, the fractional change in nonlinear parameter (Δβ/β0) and the change of precipitate phase over the aging time were fitted curve. Microstructural observations confirmed that those fluctuations are due to the formation and evolution of precipitates that occur in a unique precipitation sequence in this alloy. These results suggest that the nonlinear ultrasonic measurement can be useful for monitoring second phase precipitation in the 2219-T6 aluminum alloy.

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Authors and Affiliations

Jun You

1 2 3

Yunxin Wu

1 4 2 3

Hai Gong

1 4 2 3

Research Institute of Light Alloys, Central South University, Changsha, 410083, China
Nonferrous Metal Oriented Advanced Structural Material and Manufacturing Cooperative Innovation Center, Central South University, Changsha, 410083, China
State Key Laboratory of High-Performance Complex Manufacturing, Central South University, Changsha, 410083, China
School of Mechanical and Electrical Engineering, Central South University, Changsha, 410083, China

Wet steam flow in 1100 MW turbine

Gukchol Jun Michal Kolovratník Michal Hoznedl

Archives of Thermodynamics | 2021 | vol. 42 | No 3 | 63-85 | DOI: 10.24425/ather.2021.138110

Keywords Steam turbine Wet steam loss Non-equilibrium condensation CFD

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Abstract

The paper deals with the wet steam flow in a steam turbine operating in a nuclear power plant. Using a pneumatic and an optical probe, the static pressure, steam velocity, steam wetness and the fine water droplets diameter spectra were measured before and beyond the last turbine low-pressure stage. The results of the experiment serve to understand better the wet steam flow and map its liquid phase in this area. The wet steam data is also used to modify the condensation model used in computational fluid dynamics simulations. The condensation model, i.e. the nucleation rate and the growth rate of the droplets, is adjusted so that results of the numerical simulations are in a good agreement with the experimental results. A 3D computational fluid dynamics simulations was performed for the lowpressure part of the turbine considering non-equilibrium steam condensation. In the post-processing of the of the numerical calculation result, the thermodynamic wetness loss was evaluated and analysed. Loss analysis was performed for the turbine outputs of 600, 800, and 1100 MW, respectively.

Bibliography

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[5] Hideaki S., Tabata S. Tochitani N., Sasao Y., Takata R., Osako M.: Investigation of moisture removal on last stage stationary blade in actual steam turbine. In: Proc. ASME Turbo Expo 2020, virtual, online, Sept. 21–25, 2020, GT2020-14831.
[6] Grübel M., Starzmann J., Schatz M., Eberle T., Vogt D.M., Sieverding F.: Two-phase flow modeling and measurements in low-pressure turbines – Part I: numerical validation of wet steam models and turbine modeling. J. Eng. Gas Turbines Power 137(2015), 4, 042602 (11), GTP-14-1442.
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[13] Holmberg H., Ruohonen P., Ahtila P.: Determination of the real loss of power for a condensing and a backpressure turbine by means of second law analysis. Entropy 11 (2009), 4, 702–712.
[14] Gardzilewicz A.: Evaluating the efficiency of low pressure part of steam turbines based on probing measurements. Trans. Inst. Fluid-Flow Mach. 135(2017), 41–56.
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Authors and Affiliations

Gukchol Jun

1 2

Michal Kolovratník

2

Michal Hoznedl

1

Czech Technical University in Prague, Technická 4, 160 00, Prague, Czech Republic
Doosan Škoda Power s.r.o., Tylova 1/57, 301 28, Pilsen, Czech Republic

Heuristic energy-saving virtual network embedding algorithm based on Katz centrality

Qiang Zhu Qing-Jun Wang Mu-Jun Zang Zhen-Dong Wang Chang Xiao

Archives of Electrical Engineering | 2020 | vol. 69 | No 3 | 595-608 | DOI: 10.24425/aee.2020.133920

Keywords energy-saving virtual network integer linear programming Katz centrality network virtualization embedding virtualization

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Abstract

Current networks are designed for peak loads leading to low utilization of power resources. In order to solve this problem, a heuristic energy-saving virtual network embedding algorithm based on the Katz centrality (Katz-VNE) is proposed. For solving an energy-saving virtual network embedding problem, we introduce the Katz centrality to represent the node influence. In order to minimize the energy consumption of the substrate network, the energy-saving virtual network embedding problem is formulated as an integer linear program, and the Katz-VNE is used to solve this problem. The Katz-VNE tries to embed the virtual nodes onto the substrate nodes with high Katz centrality, which is effective, and uses the shortest paths offering the best factor of bandwidths to avoid the hot nodes. The simulation results demonstrate that the long-term average energy consumption of the substrate network is reduced significantly, and the long-term revenue/cost ratio, the acceptance rate of virtual network requests, and the hibernation rate of substrate nodes as well as links are improved significantly.

Authors and Affiliations

Qiang Zhu

Qing-Jun Wang

Mu-Jun Zang

Zhen-Dong Wang

Chang Xiao

Electrothermal Properties and RF Transmittance of Spray-coated CNT Thin Film for Radome De-icing Application

Jun Hyuk Jung Jiwon Hong Youngryeul Kim Seok-Min Yong Jinwoo Park Seung Jun Lee

Archives of Metallurgy and Materials | 2020 | vol. 65 | No 3 | 1011-1014 | DOI: 10.24425/amm.2020.133208

Keywords De-icing CNT thin film spray-coating electrothermal property RF transmittance

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Abstract

Ice formed on radome surfaces causes communication disruption due to radio-frequency interference (RFI), which reveals the importance of de-icing systems for radomes. As a radome de-icing application, in this work, carbon nanotube (CNT) thin films were fabricated using a spray-coating method, and influence of process parameters on RF transmittance and electrothermal properties was investigated. With the increase of spraying time, sheet resistance of the fabricated film decreases, which results in a decrease of the RF transmittance and improvement of the heating performance. Also, the de-icing capability of the fabricated CNT film was evaluated at –20oC, and efficient removal of ice under cold conditions was demonstrated.

Authors and Affiliations

Jun Hyuk Jung

Jiwon Hong

Youngryeul Kim

Seok-Min Yong

Jinwoo Park

Seung Jun Lee

Overburden Failure and Ground Pressure Behaviour of Longwall Top Coal Caving in Hard Multi-Layered Roof

Zhijie Zhu Yunlong Wu Jun Han Ying Chen

Archives of Mining Sciences | 2019 | vol. 64 | No 3 | 575-590 | DOI: 10.24425/ams.2019.129370

Keywords multi-layer hard roof failure of overlying strata ground pressure behaviour longwall top coal caving

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Abstract

In the extra-thick coal seams and multi-layered hard roofs, the longwall hydraulic support yielding, coal face spalling, strong deformations of goaf-side entry, and severe ground pressure dynamic events typically occur at the longwall top coal caving longwall faces. Based on the Key strata theory an overburden caving model is proposed here to predict the multilayered hard strata behaviour. The proposed model together with the measured stress changes in coal seam and underground observations in Tongxin coal mine provides a new idea to analyse stress changes in coal and help to minimise rock bursts in the multi-layered hard rock ground. Using the proposed primary Key and the sub-Key strata units the model predicts the formation and instability of the overlying strata that leads to abrupt dynamic changes to the surrounding rock stress. The data obtained from the vertical stress monitoring in the 38 m wide coal pillar located adjacent to the longwall face indicates that the Key strata layers have a significant influence on ground behaviour. Sudden dynamically driven unloading of strata was caused by the first caving of the sub-Key strata while reloading of the vertical stress occurred when the goaf overhang of the sub-Key strata failed. Based on this findings several measures were recommended to minimise the undesirable dynamic occurrences including pre-split of the hard Key strata by blasting and using the energy consumption yielding reinforcement to support the damage prone gate road areas. Use of the numerical modelling simulations was suggested to improve the key theory accuracy.

Authors and Affiliations

Zhijie Zhu

Yunlong Wu

Jun Han

Ying Chen

Stepper motor open-loop control system modeling and control strategy optimization

Deode Zhang Jingqi Wang Lei Qian Jun Yi

Archives of Electrical Engineering | 2019 | vol. 68 | No 1 | 63-75 | DOI: 10.24425/aee.2019.125980

Keywords acceleration and deceleration control open loop control stepper motor subdivision control system modeling

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Abstract

The study of the subdivision driving technology of a stepper motor and two types of typical acceleration and deceleration curves aims at optimizing the open-loop control performance of the stepper motor. The simulation model of a two-phase hybrid stepper motor open-loop control system is set up based on the mathematical model of the stepper motor, in order to let the stepper motor have the smaller stepper angle, two types of typical acceleration and a deceleration curve algorithm are designed for the real- time online calculation based on the subdivision driving technology. It respectively carries out the simulation analysis for their control effects. The simulation results show that the parabolic acceleration and deceleration curves have a larger maximum in-step rotation angle and the faster dynamic response ability in the same control period, and at the same time, the position tracking error of an intermediate process is smaller.

Authors and Affiliations

Deode Zhang

Jingqi Wang

Lei Qian

Jun Yi

Resonance mechanisms of a single line-to-ground fault on ungrounded systems

Jun Jiang Ling Liu

Archives of Electrical Engineering | 2020 | vol. 69 | No 2 | 455-466 | DOI: 10.24425/aee.2020.133037

Keywords power distribution faults single line-to-ground fault transient characteristics ungrounded distribution system

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Abstract

As for a single line-to-ground fault in an ungrounded distribution system, the power-frequency current is too low to detect the fault. The transient current is more palpable than that at a power-frequency of 50 or 60 Hz. It is an effective method to estimate the fault using the transient fault current. To analyze and calculate the transient current of single line-to-ground faults, an equivalent circuit is proposed in this paper. This model is based on distributed parameters of power lines. And it contains positive, negative and zero sequence information. The transient equivalent circuit consists of equivalent resistance, equivalent inductance and equivalent capacitance. And the method of calculation the equivalent ele- ments is also submitted.MATLAB simulation results showthat the newtransient equivalent circuit has higher accuracy and stronger adaptability compared with the traditional one.

Authors and Affiliations

Jun Jiang

Ling Liu

e-mail:

ORCID:

Reliability assessment of the port power system based on integrated energy hybrid system

Liang Fang Xiao-Yan Xu Jun Xia Tomasz Tarasiuk

Bulletin of the Polish Academy of Sciences Technical Sciences | 2022 | 70 | 2 | e140372 | DOI: 10.24425/bpasts.2022.140372

Keywords Markov model distributed generation reliability assessment integrated energy distribution power system

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Abstract

The conventional port distribution power system is being disrupted by increasing distributed generation (DG) levels based on integrated energy. Different new energy resources combine with conventional generation and energy storage to improve the reliability of the systems. Reliability assessment is one of the key indicators to measure the impact of the distributed generation units based on integrated energy. In this work, an analytical method to investigate the impacts of using solar, wind, energy storage system (ESS), combined cooling, heating and power (CCHP) system and commercial power on the reliability of the port distribution power system is improved, where the stochastic characteristics models of the major components of the new energy DG resources are based on Markov chain for assessment. The improved method is implemented on the IEEE 34 Node Test Feeder distribution power system to establish that new energy resources can be utilized to improve the reliability of the power system. The results obtained from the case studies have demonstrated efficient and robust performance. Moreover, the impacts of integrating DG units into the conventional port power system at proper locations and with appropriate capacities are analyzed in detail.

Authors and Affiliations

Liang Fang

1

Xiao-Yan Xu

1

Jun Xia

2

Tomasz Tarasiuk

3

Shanghai Maritime University, Shanghai, 201305, China
Marine Design and Research Institute of China, Shanghai, 201305, China
Gdynia Maritime University, ul. Morska 81/87, 81-225 Gdynia, Poland

Marine fishes (Elasmobranchii, Teleostei) from the Glendon Limestone Member of the Byram Formation (Oligocene, Rupelian) at site AWa-9, Washington County, Alabama, USA, including a new species of gobiid (Gobiiformes: Gobiidae)

Jun A. Ebersole David J. Cicimurri Gary L. Stringer

Acta Geologica Polonica | vol. 71 | No 4 | 481-518 | DOI: 10.24425/agp.2020.134561

Keywords Chondrichthyes Teleostei Otoliths Paleogene Gulf Coastal Plain Vicksburg Group

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Abstract

The Oligocene (Rupelian) Byram Formation (Vicksburg Group) in Alabama, USA, is divided into three members, including (in ascending order) the Glendon Limestone, unnamed marl, and the Bucatunna Clay. The Oligocene marine units in Alabama have been historically under-investigated, but bulk samples recently obtained from Glendon Limestone Member exposures at site AWa-9 in Washington County yielded 20 unequivocal elasmobranch and teleost taxa. This surprisingly diverse paleofauna, based on isolated teeth, bones and otoliths, includes the new taxon, Gobiosoma? axsmithi sp. nov., as well as “Aetomylaeus” sp., Albula sp., Aplodinotus gemma Koken, 1888, Ariosoma nonsector Nolf and Stringer, 2003, Balistidae indet., Citharichthys sp., Myliobatoidei indet., Diretmus? sp., Hemipristis sp., Negaprion aff. N. gilmorei (Leriche, 1942), Pachyscyllium sp., Paralbula sp., Physogaleus sp., Preophidion meyeri (Koken, 1888), Sciaena pseudoradians (Dante and Frizzell in Frizzell and Dante, 1965), Sciaenops? sp., Sparus? elegantulus Koken, 1888, Sphyraena sp., and Syacium sp. Additional remains were recovered but could not be identified beyond undetermined Elasmobranchii or Teleostei. All these taxa represent first occurrences within the Glendon Limestone Member in Alabama, and the “Aetomylaeus” sp., Pachyscyllium sp., Paralbula sp., and Sciaenops? sp. specimens represent the first occurrences of each in the Oligocene of the Gulf Coastal Plain of the USA. We also report the first record of Oligocene Paralbula Blake, 1940 teeth, and the first occurrence of an Oligocene member of the Balistidae in the Western Hemisphere. This marine vertebrate assemblage indicates that the Glendon Limestone Member at site AWa-9 represented a subtropical to temperate, middle shelf paleoenvironment with a paleowater depth interpreted as 30–100 m.

Authors and Affiliations

Jun A. Ebersole

1

David J. Cicimurri

2

Gary L. Stringer

3

McWane Science Center, 200 19th Street North, Birmingham, AL 35203, USA
South Carolina State Museum, 301 Gervais Street, Columbia, SC 29201, USA
Museum of Natural History, 708 University Avenue, University of Louisiana at Monroe, Monroe, LA 71209, USA

Master Curve Model for Characterization of Decomposition and Densification Behavior of PbAlNbO3-PbZrTiO3 Ceramics

Jun Sae Han Jae Man Park Seong Jin Park

Archives of Metallurgy and Materials | 2020 | vol. 65 | No 3 | 1099-1103 | DOI: 10.24425/amm.2020.133224

Keywords Master debinding curve Master sintering curve PAN-PZT Powder Injection Molding Dilatometer

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Abstract

In this study, decomposition and densification behavior of PbAlNbO3-PbZrTiO3 (PAN-PZT) ceramics were characterized for powder injection molding process. Thermal gravity analysis and in-situ dilatometer experiment were carried out to construct master curve. Based on master curve model approach, one-combined master debinding curve (MDC) and master sintering curve (MSC) were constructed for piezoelectric PAN-PZT ceramics. Derived curves matched well with the experimental data. Process optimization and material development will be conducted based on characterization of master curve parameters.

Authors and Affiliations

Jun Sae Han

Jae Man Park

Seong Jin Park

Research on the linear viscoelastic rheological properties of rejuvenated asphalt mastic based on the discrete element method

Mei Lin Yu Lei Ping Li Jun Shuai Zhaoli Wang

Archives of Civil Engineering | 2023 | vol. 69 | No 2 | 399-416 | DOI: 10.24425/ace.2023.145275

Keywords constitutive model discrete element method rejuvenated asphalt mastic rheological characteristics

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Abstract

The rheological property of asphalt is an important factor affecting the pavement performance of asphalt binder, and the fundamental reason for the change of asphalt rheological property is the strong evolution of asphalt material meso structure. However, the internal mechanism of rejuvenated asphalt mastic system is complex and its rules are difficult to grasp. Aiming to study the relationship between meso mechanical parameters and rheological parameters of rejuvenated asphalt mastic, the meso structure model of rejuvenated asphalt mastic was established and improved based on the discrete element method. Moreover, the meso parameters of the model were obtained by the objective function method, and then the influences of various factorswere studied to construct the mathematical constitutive model of rheological parameter modulus and meso mechanical parameters. Combing with the reliability of the improved Burgers model was verified based on the rheological test results of rejuvenated asphalt mastic. In addition, the virtual test of dynamic shear rheological dynamic frequency scanning was carried out on the asphalt mastic sample by particle flow software. By adjusting the mesomechanical parameters, the simulation results (complex shear modulus and phase angle)were consistent with the test results. This study clarified the relationship between mesomechanics and macro performance, and this model could be used to obtain the complex shear modulus of rejuvenated asphalt mastic under different types, filler-asphalt ratio and external force environments by adjusting particle flow, wall boundary and other conditions, which can greatly save the workload for the later research and provide a theoretical basis for production experiments.

Authors and Affiliations

Mei Lin

1

Yu Lei

1

Ping Li

1

Jun Shuai

1

Zhaoli Wang

2

School of Civil Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
Gansu Road and Bridge Green Smart Construction Technology Industry Research Institute, Lanzhou, 730030, China

A novel multiple attribute decision-making method based on Schweizer-Sklar t-norm and t-conormwith q-rung dual hesitant fuzzy information

Yuan Xu Jun Wang

Archives of Control Sciences | 2022 | vol. 32 | No 1 | 175-228 | DOI: 10.24425/acs.2022.140870

Keywords multiple attribute decision-making Schweizer-Sklar t-norm and t-conorm q-rung dual hesitant fuzzy Schweizer-Sklar Hamy mean operator q-rung dual hesitant fuzzy Schweizer-Sklar weighted Hamy mean operator

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Abstract

The recently proposed q-rung dual hesitant fuzzy sets ( q-RDHFSs) not only deal with decision makers’ (DMs’) hesitancy and uncertainty when evaluating the performance of alternatives, but also give them great liberty to express their assessment information comprehensively. This paper aims to propose a new multiple attribute decision-making (MADM) method where DMs’ evaluative values are in form of q-rung dual hesitant fuzzy elements ( q-RDHFEs). Firstly, we extend the powerful Schweizer-Sklar q-norm and t-conorm (SSTT) to q-RDHFSs and propose novel operational rules of q-RDHFEs. The prominent advantage of the proposed operations is that they have important parameters q and r, making the information fusion procedure more flexible. Secondly, to effectively cope with the interrelationship among attributes, we extend the Hamy mean (HM) to q-RDHFSs and based on the newly developed operations, we propose the q-rung dual hesitant fuzzy Schweizer-Sklar Hamy mean ( q-RDHFSSHM) operator, and the q-rung dual hesitant fuzzy Schweizer-Sklar weighted Hamy mean ( q-RDHFSSWHM) operator. The properties of the proposed operators, such as idempotency, boundedness and monotonicity are discussed in detail. Third, we propose a new MADM method based on the q-RDHFSSWHM operator and give the main steps of the algorithm. Finally, the effectiveness, flexibility and advantages of the proposed method are discussed through numerical examples.

Authors and Affiliations

Yuan Xu

1

Jun Wang

2

e-mail:

ORCID:

School of Economics and Management, Beijing Jiaotong University, Beijing 100044, China
School of Economics and Management, Beijing University of Chemical Technology, Beijing 100029, China

Multi-attribute decision-making based on q-rung dual hesitant power dual Maclaurin symmetric mean operator and a new ranking method

Li Li Jun Wang Chunliang Ji

Archives of Control Sciences | 2022 | vol. 32 | No 3 | 627-658 | DOI: 10.24425/acs.2022.142852

Keywords q-rung dual hesitant fuzzy sets power geometric dual Maclaurin symmetric mean power dual Maclaurin symmetric mean multi-attribute decision-making

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Abstract

The ability of q-rung dual hesitant fuzzy sets (q-RDHFSs) in dealing with decision makers’ fuzzy evaluation information has received much attention. This main aim of this paper is to propose new aggregation operators of q-rung dual hesitant fuzzy elements and employ them in multi-attribute decision making (MADM). In order to do this, we first propose the power dual Maclaurin symmetric mean (PDMSM) operator by integrating the power geometric (PG) operator and the dual Maclaurin symmetric mean (DMSM). The PG operator can reduce or eliminate the negative influence of decision makers’ extreme evaluation values, making the final decision results more reasonable. The DMSM captures the interrelationship among multiple attributes. The PDMSM takes the advantages of both PG and DMSM and hence it is suitable and powerful to fuse decision information. Further, we extend the PDMSM operator to q-RDHFSs and propose q-rung dual hesitant fuzzy PDMSM operator and its weighted form. Properties of these operators are investigated. Afterwards, a new MADM method under q-RDHFSs is proposed on the basis on the new operators. Finally, the effectiveness of the new method is testified through numerical examples.

Authors and Affiliations

Li Li

1

Jun Wang

2

e-mail:

ORCID:

Chunliang Ji

3

School of Economics and Management, Beihang University, Beijing 100191, China
School of Economics and Management, Beijing University of Chemical Technology, Beijing 100029, China
School of Economics and Management, Beijing Jiaotong University, Beijing100044, China

Carrollite Leaching in H2SO4-NaClO3 Media at Atmospheric Pressure

Bo Dong Jian-Hui Wu Jun Wu Xian-Peng Zhang Jing-Jun Zhai

Archives of Metallurgy and Materials | 2020 | vol. 65 | No 1 | 313-319 | DOI: 10.24425/amm.2020.131732

Keywords CuCo2S4 atmospheric leaching H2SO4-NaClO3 media

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Abstract

A new extraction process suitable for treating refractory CuCo2S4 under atmospheric pressure acidic leaching conditions was investigated. The effect of variables such as oxidant species, liquid-to-solid ratio, leaching time, oxidizing agent and mineral quality ratio, H2SO4 concentration, temperature and sodium chloride concentration on the extraction efficiency of Co, Cu and Fe from CuCo2S4 were investigated. Under optimal conditions including P80-P90 of the sample was d < 0.0074 mm, stirring speed of 400 rpm, leaching time of 8 h with sodium chlorate (NaClO3) and mineral quality ratio of 0.5, 2 mol/L H2SO4, liquid-to-solid ratio of 7, leaching temperature of 90°C and 4 mol/L sodium chloride. The leaching efficiency of Co, Cu, and Fe were nearly 97.08%, 100%, and 92.45%, respectively. Furthermore, the contents of cobalt and copper in leaching residue were all less than 0.4 wt.%, which satisfies the requirements of industrial production.

Authors and Affiliations

Bo Dong

Jian-Hui Wu

Jun Wu

e-mail:

ORCID:

Xian-Peng Zhang

Jing-Jun Zhai

Observation and Modelling on the Shipping Noise in Shallow Waters with Complex Islands and Reefs of the East China Sea

Zilong Peng Fulin Zhou Jun Fan Bin Wang Huabing Wen

Archives of Acoustics | 2021 | vol. 46 | No 2 | 301-311 | DOI: 10.24425/aoa.2021.136584

Keywords shipping noise spectral source level noise mapping shallow water merchant ship

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Abstract

The impact of the noise radiated from merchant ships on marine life has become an active area of research. In this paper, a methodology integrating observation at a single location and modelling the whole noise field in shallow waters is presented. Specifically, underwater radiated noise data of opportunistic merchant ships in the waters of Zhoushan Archipelago were collected at least one day in each month from January 2015 to November 2016. The noise data were analyzed and a modified empirical spectral source level (SSL) model of merchant ships was proposed inspired by the RANDI-3 model (Research Ambient Noise Directionality) methodology. Then combining the modified model with the realistic geoacoustic parameters and AIS data of observed merchant ships, the noise mappings in this area were performed with N×2D of Normal Mode calculations, in which the SSL of each ship was estimated using the modified model. The sound propagation at different receiving positions is different due to the shielding effect of islands and bottom topography. The methodology proposed in this paper may provide a reference for modelling shipping noise in shallow waters with islands and reefs.

Authors and Affiliations

Zilong Peng

1

Fulin Zhou

2

Jun Fan

2

Bin Wang

2

e-mail:

ORCID:

Huabing Wen

1

Institute of Noise and Vibration, School of Energy and Power Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, People’s Republic of China
Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China

Research on the Performance Optimization of Turbulent Self-Noise Suppression and Sound Transmission of Acoustic Windows Made from Functionally Graded Material

Bing Li Fu-Lin Zhou Jun Fan Bin Wang Li-Wen Tan

Archives of Acoustics | 2023 | vol. 48 | No 4 | 475-495 | DOI: 10.24425/aoa.2023.146812

Keywords functionally graded material acoustic window turbulent self-noise sound transmission loss optimization

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Authors and Affiliations

Bing Li

1

Fu-Lin Zhou

1

Jun Fan

1

Bin Wang

1

e-mail:

ORCID:

Li-Wen Tan

1

Key Laboratory of Marine Intelligent Equipment and System, Ministry of Education, P.R. China

Research on Scattering Feature Extraction of Underwater Moving Cluster Targets Based on the Highlight Model

Yang Yang Jun Fan Bin Wang

Archives of Acoustics | 2023 | vol. 48 | No 2 | 235-247 | DOI: 10.24425/aoa.2023.145235

Keywords motion small cluster targets feature fusion azimuth trend scale azimuth trend Doppler

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Abstract

In detecting cluster targets in ports or near-shore waters, the echo amplitude is seriously disturbed by interface reverberation, which leads to the distortion of the traditional target intensity characteristics, and the appearance of multiple targets in the same or adjacent beam leads to fuzzy feature recognition. Studying and extracting spatial distribution scale and motion features that reflect the information on cluster targets physics can improve the representation accuracy of cluster target characteristics. Based on the highlight model of target acoustic scattering, the target azimuth tendency is accurately estimated by the splitting beam method to fit the spatial geometric scale formed by multiple highlights. The instantaneous frequencies of highlights are extracted from the time-frequency domain, the Doppler shift of the highlights is calculated, and the motion state of the highlights is estimated. Based on the above processing method, target highlights’ orientation, spatial scale and motion characteristics are fused, and the multiple moving highlights of typical formation distribution in the same beam are accurately identified. The features are applied to processing acoustic scattering data of multiple moving unmanned underwater vehicles (UUVs) on a lake. The results show that multiple small moving underwater targets can be effectively recognized according to the highlight scattering characteristics.

Authors and Affiliations

Yang Yang

1

e-mail:

ORCID:

Jun Fan

1

Bin Wang

1

e-mail:

ORCID:

Key Laboratory of Marine Intelligent Equipment and System of the Ministry of Education, Shanghai Jiao Tong University, Shanghai, China

Development of Water-Soluble Composite Salt Sand Cores Made by a Hot-Pressed Sintering Process

Xiaona Yang Long Zhang Xing Jin Jun Hong Songlin Ran Fei Zhou

Archives of Foundry Engineering | 2023 | vol. 23 | No 3 | 51-58 | DOI: 10.24425/afe.2023.146662

Keywords Water-soluble cores Hollow composite castings Salt cores Collapsibility

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Abstract

A wide variety of water-soluble cores are widely used in hollow composite castings with internal cavities, curved channels, and undercuts. Among them, the cores made by adding binders of inorganic salts in the form of aqueous solutions have excellent solubility in water. However, excellent collapsibility is often accompanied by poor moisture absorption resistance. In this study, a water-soluble core with moderate strength and moisture absorption resistance was prepared by hot pressing and sintering the core sand mixture of sand, bentonite, and composite salts, and a tee tube specimen was cast. The experimental results showed that the cores with KCl-K2CO3 as binder could obtain strength of more than 0.9 MPa and still maintain 0.3 MPa at 80±5% relative humidity for 6 hours; the subsequent sintering process can significantly improve the resistance to moisture absorption of the hot pressed cores (0.6 MPa after 24 hours of storage at 85±5% relative humidity); the water-soluble core prepared by the post-treatment can be used to cast tee pipe castings with a smooth inner surface and no porosity defects, and it is easy to remove the core.

Authors and Affiliations

Xiaona Yang

1

Long Zhang

1

Xing Jin

2

Jun Hong

3

Songlin Ran

2

Fei Zhou

3

School of Metallurgical Engineering, Anhui University of Technology, China
Anhui Province Key Laboratory of Metallurgical Engineering & Resources Recycling, Anhui University of Technology, China
Technical Department, Anhui Highly Precision Casting Co., Ltd, China

Comparison of methods for correcting outliers in ECG-based biometric identification

Su Jun Miroslaw Szmajda Volodymyr Khoma Yuriy Khoma Dmytro Sabodashko Orest Kochan Jinfei Wang

Metrology and Measurement Systems | 2020 | vol. 27 | No 3 | 387-398 | DOI: 10.24425/mms.2020.132784

Keywords Euclidean distance autoencoders outlier correction ECG signal human identification biometrics

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Abstract

The aim of this paper is to compare the efficiency of various outlier correction methods for ECG signal processing in biometric applications. The main idea is to correct anomalies in various segments of ECG waveform rather than skipping a corrupted ECG heartbeat in order to achieve better statistics. Experiments were performed using a self-collected Lviv Biometric Dataset. This database contains over 1400 records for 95 unique persons. The baseline identification accuracy without any correction is around 86%. After applying the outlier correction the results were improved up to 98% for autoencoder based algorithms and up to 97.1% for sliding Euclidean window. Adding outlier correction stage in the biometric identification process results in increased processing time (up to 20%), however, it is not critical in the most use-cases.

Authors and Affiliations

Su Jun

Miroslaw Szmajda

Volodymyr Khoma

Yuriy Khoma

Dmytro Sabodashko

Orest Kochan

Jinfei Wang

Design and evaluation of a needle tip measurement system based on binocular vision

Yuyang Lin Yunlai Shi Jun Zhang Fugang Wang Haichao Sun

Metrology and Measurement Systems | 2020 | vol. 27 | No 3 | 495-512 | DOI: 10.24425/mms.2020.134593

Keywords needle tip measurement binocular vision system measurement capability analysis non-contact optical positioning

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Abstract

The precise location of the needle tip is critical in robot-assisted needle-based percutaneous interventions. An automatic needle tip measuring system based on binocular vision technology with the advantages of non-contact, excellent accuracy and high stability is designed and evaluated. First the measurement requirements of the prostate intervention robot are introduced. A laser interferometer is used as the reference for measuring the position of the needle tip whose relative position variation is described as the needle tip distance in the time domain. The parameters of the binocular cameras are obtained by Zhang’s calibration method. Then a robust needle tip extraction algorithm is specially designed to detect the pixel coordinates of the needle tip without installing the marked points. Once the binocular cameras have completed the stereo matching, the 3D coordinates of the needle tip are estimated. The measurement capability analysis (MCA) is used to evaluate the performance of the proposed system. The accuracy of the system can be controlled within 0.3621 mm. The agreement analysis is conducted by the Bland–Altman analysis, and the Pearson correlation coefficient is 0.999847. The P/T ratio value is 16.42% in the repeatability analysis. The results indicate that the accuracy and stability of the binocular vision needle tip measuring system are adequate to meet the requirement for the needle tip measurement in percutaneous interventions.

Authors and Affiliations

Yuyang Lin

Yunlai Shi

Jun Zhang

e-mail:

ORCID:

Fugang Wang

Haichao Sun

Assessing system impedance based on data regrouping

Shuangting Xu Xianyong Xiao Yang Wang Jun Wu

Metrology and Measurement Systems | 2021 | vol. 28 | No 1 | 191-208 | DOI: 10.24425/mms.2021.136002

Keywords system impedance passive method Thevenin equivalent power system

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Abstract

In recent years, assessing supply system impedance has become crucial due to the concerns on power quality and the proliferation of distributed generators. In this paper, a novel method is shown for passive measurement of system impedances using the gapless waveform data collected by a portable power quality monitoring device. This method improves the overall measurement accuracy through data regrouping. Compared with the traditional methods that use the consecutive measurement data directly, the proposed method regroups the data to find better candidates with less flotation on the system side. Simulation studies and extensive field tests have been conducted to verify the effectiveness of the proposed method. The results indicate that the proposed method can serve as a useful tool for impedance measurement tasks performed by utility companies.

Authors and Affiliations

Shuangting Xu

1

Xianyong Xiao

1

Yang Wang

1

Jun Wu

2

e-mail:

ORCID:

Sichuan University, The College of Electrical and Engineering, Chengdu 610065, China
Electric Power Research Institute of State Grid Zhejiang Electric Power Company, Hangzhou 310014, China

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