Wyniki wyszukiwania - BazTech

1

Prediction and validation for the aerodynamic noise of high-speed train power car

Jiang S., Yang S., Wu D., Wen B-Ch.

Transport Problems

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2018

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T. 13, z. 2

91--102

EN

The aerodynamic noise of high-speed train power car was investigated in this article. The full-scale power car was first modeled, and the external steady flow field was computed by a realizable k-ε turbulence model. The aerodynamic noise sources of the power car surface and the external transient flow field were then calculated by broadband noise source model and large eddy simulation (LES) model, respectively. The static pressures on the train surface were obtained from the results of the transient model. Considering the transient flow field, the far-field aerodynamic noise generated by the power car was finally derived from Lighthill-Curle theory. It was validated by means of on-line tests that have been performed along a real high-speed railway line. Through comparisons between simulations and measurements, it is shown that the simulation model gives reliable aerodynamic noise predictions. We foresee numerous applications for modeling and control of the aerodynamic noise in high-speed train.

2

Quantitative analysis of the relationship between shear strength and fractal dimension of solidified dredger fill with different fly ash content under monotonic shear

Yang S., Liu W., Liu H.

Polish Maritime Research

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2018

|

S 2

132--138

EN

The dredger fill of Shanghai Hengsha Island Dongtan is solidified by curing agents with different fly ash content, and the shear strength index of solidified dredger fill is measured by the direct shear test. The microscopic images of solidified dredger fill are obtained by using SEM. The microscopic images are processed and analyzed by using IPP, and the fractal dimension including particle size fractal dimension Dps, aperture fractal dimension Dbs and particle surface fractal dimension Dpr is calculated by fractal theory. The quantitative analysis of the relationship between shear strength index and fractal dimension of solidified dredger fill is done. The research results show that the internal friction angle and the cohesion are closely related to the fly ash content λ and the curing period T, and the addition of fly ash can improve the effect of curing agent; There is no obvious linear relationship between the internal friction angle and the three fractal dimensions; The smaller particle surface fractal dimension Dpr and particle size fractal dimension Dps, the larger aperture fractal dimension Dbs, the greater the cohesion, and the cohesion has a good linear relationship with three fractal dimensions, and the correlation coefficient R2 is above 0.91.

3

Swarm intelligence algorithm based on competitive predators with dynamic virtual teams

Yang S., Sato Y.

Journal of Artificial Intelligence and Soft Computing Research

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2017

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Vol. 7, No. 2

87--101

EN

In our previous work, Fitness Predator Optimizer (FPO) is proposed to avoid premature convergence for multimodal problems. In FPO, all of the particles are seen as predators. Only the competitive, powerful predator that are selected as an elite could achieve the limited opportunity to update. The elite generation with roulette wheel selection could increase individual independence and reduce rapid social collaboration. Experimental results show that FPO is able to provide excellent performance of global exploration and local minima avoidance simultaneously. However, to the higher dimensionality of multimodal problem, the slow convergence speed becomes the bottleneck of FPO. A dynamic team model is utilized in FPO, named DFPO to accelerate the early convergence rate. In this paper, DFPO is more precisely described and its variant, DFPO-r is proposed to improve the performance of DFPO. A method of team size selection is proposed in DFPO-r to increase population diversity. The population diversity is one of the most important factors that determines the performance of the optimization algorithm. A higher degree of population diversity is able to help DFPO-r alleviate a premature convergence. The strategy of selection is to choose team size according to the higher degree of population diversity. Ten well-known multimodal benchmark functions are used to evaluate the solution capability of DFPO and DFPO-r. Six benchmark functions are extensively set to 100 dimensions to investigate the performance of DFPO and DFPO-r compared with LBest PSO, Dolphin Partner Optimization and FPO. Experimental results show that both DFPO and DFPO-r could demonstrate the desirable performance. Furthermore, DFPO-r shows better robustness performance compared with DFPO in experimental study.

4

Measurement of the Heat of Reaction of Polytetrafluoroethylene/Aluminum Composites Based on Laser Initiation

Li S., Wu Y., Lin Q., Huang C., Yang S., Li J.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

534--546

EN

Polytetrafluoroethylene/aluminum (PTFE/Al) composites are reactive materials which can release energy due to exothermic chemical reactions initiated under shock loading conditions. In order to accurately measure the potential maximum heat of reaction of PTFE/Al composites in an inert atmosphere, we propose in this paper a heat of reaction measurement system based on laser initiation. Our results show that the measurement system successfully initiates the chemical reaction between PTFE and Al in an argon atmosphere. The comparison between theoretical calculations and experimental data demonstrates that our measurement method is highly accurate and exhibits excellent consistency. Thus, the heat of reaction measurement system based on laser initiation is applicable for measuring the heat of reaction of PTFE/Al composites and also other complicated reactive materials.

5

Magnetic Properties of (Nia-Znb)X Cu1-X Ferrite Nanoparticle Fabricated by Sol-Gel Process

Yang S., Kim J.-G.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1197--1200

EN

In future, more mobile devices with different frequencies will be used at the same time. Therefore, it is expected that the trouble caused by wave interference between devices will be further intensified. In order to prevent this trouble, investigation of selective frequency transmission or absorption material is required. In this paper, magnetic properties of nickel-zinc-copper ferrite nano powder was researched as wave absorber. (Nia-Znb)xCu1-xFe2O4(NZCF) nanoparticles were fabricated by the sol-gel method. The influence of copper substitution on lattice parameter change was analyzed by X-ray diffraction (XRD), particle size was analyzed by scanning electron microscopy (SEM), and Magnetic properties analyzed by vibrating sample magnetometer (VSM). The NZCF and Nickel-zinc ferrite (NZF) lattice parameter difference was 0.028 Å and particle size was calculated as 30 nm with the XRD peak. The VSM results of (Ni0.3-Zn0.3)0.6Cu1-0.6Fe2O4 annealed sample at 700°C for 3hous were 58.5 emu/g (Ms), 22.8 Oe (Hc). It was the most suitable magnetic properties for wave absorber in this investigation.

6

Influence of Substituted Elements on Reflection Loss of Ba-Ferrite Nanoparticle

Yang S., Jeong K.-P., Park S.-Y., Kim J.-G.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1201--1204

EN

Due to the rapid development of the information communication industries, it is expected that next-generation mobile communication devices in the data communication environment will be used at the same time in the L~X band (1–12 GHz). To mutual electric wave interference prevention, research on wave absorbers in L~X band is needed. In this paper, barium ferrite was researched as L~X band wave absorber. The Barium ferrite (BaM, Ba ferrite) substituted by divalent ions (Co2+, Cu2+, Ni2+, Zn2+) and tetravalent ion (Ti4+). The substituted Ba ferrite nanoparticles were fabricated by sol-gel process. Lattice parameter, particle size, magnetic properties, and reflection loss were analyzed by X-ray diffraction (X-RD), a Vibrating Sample Magnetometer (VSM), and a Network Analyzer. Lattice parameter of Ba ferrite was changed 0.0005 to 0.0078 Å in a-b direction, and 0.0187 to0.0445 Å in c-direction by substituted elements, and it influenced on magnetic anisotropy. In addition, Co-Ti substitution elements influenced that coercive force decrease 5,739 to 2,240 Oe. Moreover, reflection loss frequencies were shifted from 16.3 GHz to 14.4 and 17.4 GHz by substituted elements Co-Ti and Zn-Ti.

7

Analysis of the influence of the transducer and its coupling layer on round window stimulation

Liu H., Xu D., Yang J., Yang S., Cheng G., Huang X.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 2

103--111

EN

Purpose: In this work, a finite element study is proposed to evaluate the effects of the transducer and its coupling layer on the performance of round window (RW) stimulation. Methods: Based on a set of micro-computer tomography images of a healthy adult’s right ear and reverse engineering technique, a coupled finite-element model of the human ear and the transducer was constructed and verified. Then, the effect of the cross-section of the transducer, the elastic modulus of the coupling layer, the mass of the transducer, and the preload of the transducer were studied. Results: The increase of the transducer’s cross-section area deteriorates the RW stimulation, especially at the lower frequencies. This adverse effect of the cross-section area’s increase of the transducer can be reduced by adding a coupling layer between the transducer and the RW. However, the coupling layer’s improvement on the RW stimulation is reduced with the increase of its elastic modulus. Moreover, the mass loading of the transducer decreases the RW stimulation’s performance mainly at higher frequencies and applying a static preload on the transducer enhances its hearing compensating performance at higher frequencies. Conclusions: The influence of the transducer’s mass, the mass of the transducer, the applied static preload and the properties of the coupling layer must be taken into account in the design of the RW stimulation type implantable middle ear hearing device.

8

Capillary column coated with geminal ionic liquids as stationary phases for gas chromatographic separation

Jiang R., Yang S., Luo A.

Acta Chromatographica

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2017

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Vol. 29, no. 1

25--43

EN

Four geminal ionic liquids (GILs), namely, 1,4-bis(1,1′-butyl-3,3′- methylene- imidazolium)-benzene bis[(trifluoromethyl)sulfonyl]imide (BBMIB-NTf2), 1,4- bis(1,1′-butyl-3,3′-methylene-imidazolium)-benzene tetrafluoroborate (BBMIB-BF4), 1,4- bis(1,1′-butyl-3,3′-methylene-imidazolium)-benzene hexafluophosphate (BBMIB-PF6), and 1,4-bis(1,1′-methyl-3,3′-methylene-imidazolium)-benzene bis[(trifluoromethyl) sulfonyl] imide (BMMIB-NTf2), were synthesized. They were statically coated onto the inner walls of fused-silica capillary columns and used as stationary phases for gas chromatography. The evaluation of BBMIB-NTf2, BBMIB-BF4, BBMIB-PF6, and BMMIB-NTf2 as stationary phases is reported here for the first time. These new stationary phases exhibit efficiencies of at least 2.3 × 103 plates per meter. Abraham solvation parameter model was used to evaluate the solvation characteristics. The system constants indicated that the dipolarity/polarizability and the hydrogen-bond basicity play a major role among five molecular interactions between stationary phases and solute molecules. A fundamental understanding into the solvation characteristics of these GILs can be used as a guide to choosing the appropriate geminal ionic liquids for specific applications in various fields. The chromatographic separation performance was evaluated by a Grob test mixture, n-alkanes, alcohols, and aromatic isomers. Furthermore, the thermal stability was tested. The present results demonstrate that these geminal ionic liquids stationary phases possess excellent chromatographic separation performance and good thermal stability (at least up to 270 °C) and may be applicable as gas chromatography stationary phases for more application.

9

Beneficial effects and mechanism of lead ion on wolframite flotation

Yang S., Qiu X., Peng T., Chang Z., Feng Q., Zhong C.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

855--873

EN

In this study the effects and mechanism of lead ions influence on wolframite flotation with benzohydroxamic acid (BHA) were studied through micro-flotation, adsorption experiments, zeta potential measurements, logarithmic concentration diagram, and X-ray photoelectron spectroscopy. It was observed that lead ions could significantly enhance the recovery of wolframite in flotation and adsorption density of collector BHA onto the wolframite surface. The results showed that Pb existed in the forms of lead ion, monohydric lead, and lead hydroxide at the water-wolframite interface respectively, at three pH ranges. They increased the zeta potential of wolframite. However, the zeta potential of wolframite was still negative, resulting in repulsive electrostatic force to anionic collector BHA. Combining with XPS spectra, it revealed the chemisorption of BHA onto the wolframite surface. In addition, PbO or Pb(OH)2 was observed on the wolframite surface due to the reaction between lead ions and wolframite. These reaction products increased the adsorption site of BHA on the wolframite surface because Pb-hydroxamate was found on the wolframite surface.

10

Anchoring principles of a new energy-absorbing expandable rock bolt

Wen Z., Jiang Y., Han Z., Yang S., Wang X.

Engineering Transactions

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2016

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Vol. 64, iss. 1

89--103

EN

The greater the mine, the harder stability control will be. And the conventional rock bolts do not adapt well to the severe rock stress conditions. An ideal bolt having a high resistance and large deformation should be developed. Based on the test results and theoretical study, this paper proposes an energy-absorbing expandable rock bolt, which consists of the bar, sleeve, bolt plate, nut, and bolt end. The anchoring mechanism and its efficiency were systematically analysed in the laboratory and in practice: the anchoring mechanism and supporting density, especially the quantitative relationship, were deduced under the Energy Balance Theory, that is, EB = 1 2 · n · F0 (u0 + 2∆u). As Compared with the conventional bolt and large deformation bolts, the new type of bolt could provide a larger constant resistance, even in the soft rock roadway with large squeezing deformation, the pulling force can be achieved by F = A · σ · f2, it mainly being generated by a normal stress acting on the pore surface. These characteristics are helpful in making the supported roadway safe. The amount of released energy during the large deforming process of the surrounding rock is expressed through conservation of energy, which can provide reference to the quantitative calculation of the bolt supporting system.

11

Polybrominated diphenyl ethers (PBDEs) in sediment and fish tissues from Lake Chaohu, central eastern China

Yang S., Fu Q., Teng M., Yang J.

Archives of Environmental Protection

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2015

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Vol. 41, no. 2

12--20

EN

Polybrominated diphenyl ethers (PBDEs) levels in environmental media have increased over the last 20-25 years in the world. In aquatic environments PBDEs were found to be accumulated along food chain and Endocrine disruptors toxicity. In this study PBDEs were investigated in sediment and fish tissues from Lake Chaohu in central eastern China. There were 10 PBDEs congeners detected out of all 41 PBDEs. BDE-47 was of the highest with 5.17 ng/g in sediment and 58.47 ng/g in fish. PBDEs were evenly distributed across the surface sediment in the whole lake. It implied that the main source of PBDEs may not be an inflow river like Nanfei. Tissue distribution patterns of PBDEs in four fish species were in the order of BDE-47 > BDE-99 > BDE-100 > BDE-66 > BDE-138 > BDE-183 > BDE-154 > BDE-153. Octa- and deca-BDEs were below the detection limit. The concentrations of all PBDE congeners were higher in gills, livers, and kidneys than those in muscles and adipose tissue. Furthermore, PBDEs in different tissues had some different distribution patterns with fish size. Those discrepancies appeared to be correlated with the PBDEs pollution fluxes varying with the change of the year and their metabolism divergences in fish tissues.

12

Relationship between flotation and Fe/Mn ratio of wolframite with benzohydroxamic acid and sodium oleate as collectors

Yang S., Feng Q., Qiu X., Gao Y., Xie Z.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

747--758

EN

Several studies revealed that flotation of wolframite changes with different Fe/Mn ratios, but they did not reach a consensus. This relationship in the presence of benzohydroxamic acid (BHA) and sodium oleate (NaOl) as collectors was studied in this paper through comparison of probability distribution curve of wolframite with different Fe/Mn ratios between the raw ore and the flotation concentrate, the pure mineral flotation and solution chemistry of flotation. The results showed that wolframite with high Fe/Mn ratio showed higher flotation with BHA as a collector while the flotation behavior of wolframite was completely opposite with NaOl as a collector. Besides, the calculations of chemical equilibrium in the solution were plotted as ΔG°-pH graphs. The results revealed that the flotation of wolframite may be determined by the interaction between BHA and ferric(II) ion or between NaOl and manganous ion. From the perspective of collector mixture, the results also explain the high collecting capability of the BHA/NaOl collector mixture, which can be defined as “functional complementation”.

13

Short Term Load Forecasting Based on WLS-SVR and TGARCH Error Correction Model in Smart Grid

Hou L., Yang S., Wang X., Shen J.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 3b

170--175

EN

Smart grid is the main development goal of future power grid while the short-term load forecasting is the significant premise of making management, power supply and trading plan in market circumstance. The forecasting accuracy directly determined the safety and economy of electric system. Support Vector Machines (SVM), as the new machine learning method, has applied successfully to short-termed load forecasting. However, research finds out that the singular points of the initial data have impact on forecasting accuracy. So in this paper, firstly, based on the analysis of SVM, we render Weighted Least Square and Support Vector Regression (WLS-SVR) applying to short-termed load forecasting, which overcomes the disadvantage of singular points. Secondly, we offer Threshold Generalized Autoregressive Conditional Heteroskedasticity (TGARCH) model to construct error prediction model to modify the initial predicted value. Finally, according to the PJM historical data, we get the results showing that the accuracy is greatly improving by implementing our methods which makes our methods founded.

PL

W artykule przedstawiono model przewidywania krótkookresowego obciążenia sieci elektroenergetycznej. W proponowanym rozwiązaniu wykorzystano metodę SVM (ang. Support Vector Machine). W celu eliminacji istniejącego wpływu wartości syngularnych na dokładność wyniku, zastosowano regresję ze średnią ważoną. Dodatkowo wykorzystano model TGARCH w określaniu błędów predykcji. Przedstawiono wyniki badań weryfikacyjnych, przeprowadzonych na rzeczywistych danych.

14

Apply to the Township's Small Substation

Ding S., Xiao L., Huang R., Liu J., Yang S., Chai X.

Przegląd Elektrotechniczny

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2013

|

R. 89, nr 3b

13--14

EN

This paper designed a small terminal of a 35kV substation; it can meet the substation area electricity and the future development of the needs of the vision of growth in electricity demand. The article presents the design of transformers, substation main connection, and lightning protection. The practice shows that it applies to the township (town) of agricultural load and small-scale processing enterprises in electricity.

PL

W artykule przedstawiono projekt przyłącza podstacji elektroenergetycznej 35kV. W opisie uwzględniono projekt transformatorów, głównego przyłączenia podstacji oraz ochronę odgromową. W praktycznym ujęciu, projekt może mieć zastosowanie w rejonach agroturystycznych i niewielkich zakładach.

15

Preparation and properties of low temperature sintered CaO-B2O3-SiO2 microwave dielectric ceramics using the solid-state reaction

Zhou X., Li E., Yang S., Li B., Tang B., Yuan Y., Zhang S.

Materials Science Poland

|

2013

|

Vol. 31, No. 3

404--409

EN

The LTCC CaO–B2O3–SiO2 (CBS) ceramics were synthesized via solid-state reaction process without any sintering aid. The effects of different sintering temperatures and B2O3 content on the microwave and mechanical properties were investigated. The results show that the best sintering temperature is around 950 °C and increasing amount of B2O3 promotes the crystallization of CaB2O4 enhancing the flexure strength of the CBS ceramics. However, the dielectric and mechanical properties deteriorated rapidly while the amount of B2O3 exceeded 25 wt.%. The sample with 20.5 wt.% B2O3 sintered at 950 °C had the best properties with er = 6.06; tand = 0.0015 (1 MHz) and a high flexure strength qf > 180 MPa.

16

The Hierarchical-Cluster Topology Control Strategy of InterPlaNetary Internet Backbone based on Libration Points

Jiang Y., Li G., Zhang G., Yang S.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 4a

271-276

EN

The concept of InterPlaNetary (IPN) Internet was proposed by National Aeronautics and Space Administration (NASA). The IPN Internet could provide Internet-like services crossing interplanetary distances in support of deep space exploration, which includes backbone network, access network, and planetary network. The IPN backbone topology control strategy based on Libration points was studied in this paper. Firstly, the location and stability of Libration point is simulated by celestial mechanics. Secondly, a novel Hierarchical-Cluster model of IPN backbone network is proposed to simplify topology design. Then Intra-Cluster Link and Inter-Cluster Link are analyzed in detail. Finally, the optimal handover moment is gotten by critical angle which to use relay theory, and the total number of handover times is calculated within a relative period between Uranus and Neptune cluster.

PL

Koncepcja interplanetarnego Internetu IPN została zaproponowana przez NASA. W artykule omówiono strategię kontroli topologii szkieletu bazującą, na punkcie Libration. Na wstępie przeanalizowano stabilność systemu a następnie model hierarchiczny klastrów. Wreszcie analizowano przełączenie połączeń między stacjami bazowymi – handover.

17

Intelligent Digital Multi-purpose Vehicle Instrument

Ding S., Li J., Xiao L., Huang R., Yang S.

Przegląd Elektrotechniczny

|

2012

|

R. 88, nr 5b

64-67

EN

This paper analyzed and studied the development and needs of the vehicle instrument. By the electronic circuit and microcontroller technologies it achieved the high-precision digital display of the speed, and the mileage and the fuel, and also this vehicle instrument realized the function of password protection, and alcohol concentration detection and reversing radar measuring the distance. Practice shows that the digital vehicle instrument has an intuitive digital display and high intelligence.

PL

Przedstawiono nowy inteligentny mikroprocesorowy instrument pokładowy samochodu. Instrumetn pozwala nie tylko mierzyć prędkość i dystans, ale także wykrywa obecność alkoholu i działanie radaru.

18

A Token-Managed Admission Control System for QoS Provision on a Best-Effort GALS Interconnect

Yang S., Furber S.B., Shi Y., Plana L.A.

Fundamenta Informaticae

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2009

|

Vol. 95, nr 1

53-72

EN

A Token-ManagedAdmission Control (TMAC) mechanism is introduced in order to provide efficient Quality-of-Service (QoS) support for different types of application on a best-effort Globally-Asynchronous Locally-Synchronous (GALS) interconnect fabric. The mechanism is applied at the ingress edges of the fabric using tokens to allocate dynamic network resources and prevent network congestion. The degree of fairness is controllable, in order to balance the desired throughput and data transfer resource allocation appropriately for a particular application. The simulation and analysis presented here shows efficient QoS provision. Our detailed implementation and analysis show that TMAC provides service guarantees on the network while using a modest physical area because of the simplicity of the control logic.

19

Kinetic determination of Cr2O72- by chemical oscillation method

Liu Y., Yang F., Wang C., Long S., Yang S.

Chemia Analityczna

|

2009

|

Vol. 54, No. 6

1397-1404

EN

The influence of Cr2O72-on the B-Z oscillating reaction has been studied. The research results have shown that B-Z oscillating reaction can be paused by Cr2O72- and the pause time can be used as a kinetic parameter in determination of Cr2O72- (when perturbed by particular chemicals, stable oscillating reaction is inhibited or paused; pause duration of the oscillation phenomenon is defined as a pause time). Under optimum experimental conditions, the pause time was linearly proportional to the concentration of Cr2O72-in the range 4.74 x 10-61.20x10-6 mol L-1 (r = 0.999), detection limit was 1.32 x 10 x10-8 L-1 The influence of more than 15 coexisting ions on determination of Cr2O72- was investigated in details. Most cations and anions had little effect on the determination results of Cr2O72-. A possible disturbance mechanism of Cr2O72- on the oscillating system was discussed. As a particularly efficient oxidant. Cr2O72- could consume Br quickly. Due to the extra consumption of Br. the B-Z oscillating reaction was inhibited, and therefore paused for a particular time (pause time). The higher the concentration of Cr2O72- was, the longer the pause time became, until the B-Z oscillating reaction was quenched completely.

PL

Badano wpływ Cr2O72- na reakcję oscylacyjną B-Z. Wyniki wskazywały, że reakcja może być przerwana pr/ez Cr2O72- a czas przerwy może być zastosowany jako kinetyczny parametr oznaczania Cr2O72- (gdy reakcja jest zaburzana przez jakiś dodatkowy składnik, stabilna oscylacja jest spowolniona lub przerwana a czas zaburzenia oscylacji jest określany jako czas pr/erwy). W optymalnych warunkach czas przerwy jest wprost proporcjonalny do stężenia Cr,O; w zakresie 4.74 x 10^-1.20 x I0~4 mol L~' (r = 0,999). granica wykrywalności 1.32 x 10"* mol L"'. Przebadano wpływ współwystępowania 15 różnych jonów na o/naczenie Cr2O72-. Większość kationów i anionów miała niewielki wpływ na oznaczanie Cr2O72-; . Przedyskutowano prawdopodobny mechanizm zaburzania reakcji oscylacyjnej przez Cr2O72- jako szczególnie efektywny utleniacz, mógł szybko usuwać join Br . / powodu zwiększonego usuwania jonów Br, reakcja oscylacyjna B-Z ulegała zahamowaniu i zatrzymywała się na pewien czas. Im większe było stężenie Cr2O72-, tym dłuższy był czas przerwy, aż do całkowitego wygaszenia reakcji oscylacyjnej B-Z.

20

A note on sequence-covering images of metric spaces

Yang S.

Fasciculi Mathematici

|

2007

|

Nr 38

125-129

EN

In this paper, we prove that every topological space is a sequence-covering image of a metric space, which answers a question on pseudo-sequence-covering images of metric spaces.