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1

A high-sensitivity photonic crystal fiber (PCF) based on the surface plasmon resonance (SPR) biosensor for detection of density alteration in non-physiological cells (DANCE)

Wang F., Sun Z., Liu C., Sun T., Chu P. K.

Opto-Electronics Review

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2018

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Vol. 26, No. 1

50--56

EN

A highly sensitive photonic crystal fiber based on the surface plasmon resonance (PCF-SPR) biosensor for the detection of the density alteration in non-physiological cells (DANCE) is described. Human acute leukemia cells are determined by the discontinuous sucrose gradient centrifugation (DSGC) in which the cells are separated into several bands. The separated cells with different intracellular densities and refractive indexes (RI) ranging from 1.3342 to 1.3344 are distinguished in situ by means of the differential transmission spectrum. The biosensor shows a maximum amplitude sensitivity of 2000 nm/RIU and resolution as high as 5 × 10⁻⁵ RIU. According to the wavelength interrogation method, a maximum spectral sensitivity of 9000 nm/RIU in the sensing range between 1.33 and 1.53 is achieved, corresponding to a resolution as high as 1.11 × 10⁻⁵ 5RIU for the biosensor. The proposed PCF-SPR biosensor has promising application in biological and biochemical detection.

2

Numerical Study of Extra-Large Parachute’s Pre-Inflation in Finite Mass Situation

Sun Z., Cheng H., Yang J.

Autex Research Journal

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2018

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Vol. 18, no. 2

130--136

EN

The extra-large parachutes were different from the common parachutes because of their size and opening process. Some undesirable inflation phenomena such as canopy winding and whipping usually appeared in their pre-inflation process. However, the mechanical mechanism of these phenomena was very difficult to be explained by experimental means. In this paper, the pre-inflation process in finite mass situation of an extra-large parachute was calculated by explicit finite elements. According to the results, the pre-inflation process can be subdivided into symmetric inflation stage, undesirable inflation stage, and stable inflation stage. The canopy winding and whipping mainly occurred in the second stage. With the continuous deceleration of parachute-payload system, the top of canopy without effective constraints would appear winding and whipping under the function of inertia force. The canopy winding and whipping increased the difficulty of canopy expanding and then caused asymmetric inflation. The above undesirable phenomena had a great influence on the deceleration effect and were easy to cause the recovery failure. The actual airdrop experiments also proved that the lack of effective constraints on the canopy top will cause undesirable inflation phenomena. The conclusions in this paper can also provide a reference for extra-large parachute design and research.

3

Effect of water flows on ship traffic in narrow water channels based on cellular automata

Hu H., Chen X., Sun Z.

Polish Maritime Research

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2017

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S 3

130--135

EN

In narrow water channels, ship traffic may be affected by water flows and ship interactions. Studying their effects can help maritime authorities to establish appropriate management strategies. In this study, a two-lane cellular automation model is proposed. Further, the behavior of ship traffic is analyzed by setting different water flow velocities and considering ship interactions. Numerical experiment results show that the ship traffic density-flux relation is significantly different from the results obtained by classical models. Furthermore, due to ship interactions, the ship lane-change rate is influenced by the water flow to a certain degree.

4

Dynamic Characteristic Analysis of the Needle Multi-linkage Mechanism in a Carpet Tufting Machine’s Driving System

Xu Y., Sun Z., Huang S., Sheng X., Chi X.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 3 (117)

103--109

EN

In a typical carpet tufting machine, kinematic and dynamic characteristics of the needle multi-linkage mechanism are the important factors affecting the quality of the tufting carpet. For providing a rational basis for mechanism design and vibration characteristic analysis, a mathematical model of the needle multi-linkage mechanism is constructed using the complex vector analysis method. On the basis of the model, kinematic characteristic curves and dynamic characteristic curves of the needle multi-linkage mechanism are analyzed by simulation methods. Finally experimental validation of the alternating load dynamic characteristics is performed on the needle multi-linkage mechanism in a typical carpet tufting machine. The results prove the theoretical analysis validity of the needle multi-linkage mechanism.

PL

W typowej maszynie wiążącej dywany charakterystyki kinematyczne i dynamiczne mechanizmu napędzającego układ igieł są bardzo ważnym czynnikiem określającym jakość wytwarzanych dywanów. Dla otrzymania racjonalnej podstawy dla projektowania mechanizmu i analizy charakterystyk wibracyjnych opracowano matematyczny model mechanizmu napędzającego igły. Przy opracowaniu modelu zastosowano metodę kompleksowej analizy wektorowej. Posłużyło to do otrzymania kinematycznych i dynamicznych krzywych przebiegu. Przebiegi te analizowano za pomocą metod symulacji. Następnie oceniono wyniki eksperymentalnie stosując typową maszynę do wytwarzania dywanów. Wyniki potwierdziły prawidłowość przyjętych teoretycznie zależności.

5

Hardening strain and recovery strain in nanocrystalline Ni investigated in tests with multiple stress changes

Sun Z., Blum W.

Archives of Materials Science and Engineering

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2016

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Vol. 79, nr 2

53--59

EN

Purpose: Dynamic recovery is interesting as it limits the maximal deformation strength of crystalline materials. Due to its small grain size, nanocrystalline Ni reaches its maximal strength after small strains < 0.1. It is shown that dynamic recovery contributes to strain and that its kinetics differs from that of hardening strain. Design/methodology/approach: The kinetics of recovery was studied by performing a large stress reduction suppressing thermally activated glide of the hardening type. The transition to a new quasi-stationary state at reduced strain rate and stress was accelerated by incremental increases of stress. Findings: During the transition the kinetics of deformation changes from that of recovery strain to the quasi-stationary one where hardening and recovery are coupled. The results are interpreted in terms of thermally activated hardening strain (in the grains) and thermally activated recovery strain (boundary mediated) linked by internal stresses. The activation volume of the hardening strain rate determined from the small stress increments is not inconsistent with the classical theory of thermally activated dislocation glide. Research limitations/implications: It is proposed to better characterize dynamic recovery by performing small stress changes in the period of dominating recovery strain to quantify the kinetics parameters of recovery strain. Practical implications: Disturbing deformation by sudden changes of stress is recommended as a suitable means to describe the kinetics of dynamic recovery. Recovery strains should enter the modeling of plastic deformation. This holds in particular for cases where dynamic recovery is prominent, e.g. at high stresses, high temperatures, and variable stresses (cyclic deformation, stress relaxation). Originality/value: The stress change method described in this work is generally applicable in deformation testing independent of the type of testing machine, where inelastic strains are measured at the usual accuracy.

6

Water Storage Changes over the Tibetan Plateau Revealed by GRACE Mission

Guo J., Mu D., Liu X., Yan H., Sun Z., Guo B.

Acta Geophysica

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2016

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Vol. 64, no. 2

463--476

EN

We use GRACE gravity data released by the Center for Space Research (CSR) and the Groupe de Recherches en Geodesie Spatiale (GRGS) to detect the water storage changes over the Tibetan Plateau (TP). A combined filter strategy is put forward to process CSR RL05 data to remove the effect of striping errors. After the correction for GRACE by GLDAS and ICE-5G, we find that TP has been overall experiencing the water storage increase during 2003-2012. During the same time, the glacier over the Himalayas was sharply retreating. Interms of linear trends, CSR’s results derived by the combined filter are close to GRGS RL03 with the Gaussian filter of 300-km window. The water storage increasing rates determined from CSR’s RL05 products in the interior TP, Karakoram Mountain, Qaidam Basin, Hengduan Mountain, and middle Himalayas are 9.7, 6.2, 9.1, –18.6, and –20.2 mm/yr, respectively. These rates from GRGS’s RL03 products are 8.6, 5.8, 10.5, –19.3 and –21.4 mm/yr, respectively.

7

Physical purification of diatomite based on laminar-flow centrifugal separation

Yang X., Sun Z., Zheng S.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

705--718

EN

Natural diatomaceous earth or diatomite of good quality becomes rare and a demand for it increases every year. In this paper, we develop a novel method based on laminar-flow centrifugal separation to purify mid- and low-grade diatomite for industrial production purposes. Effects of the drum cone angle, drum speed, feeding concentration, feeding flow rate and feeding time on separation were investigated experimentally. The interdependency of these variables was studied using a response surface experiment. Operating conditions of a laminar-flow centrifugal separator were further optimized. Results showed that the feeding flow rate had a great influence on a silicon dioxide content of diatomaceous in concentrate and tailing. The optimal separation results were achieved as 87.5 wt.%, of SiO2 content of diatomaceous in concentrate and 6.98 wt.% in tailing. The optimal operating conditions included the drum cone angle of 0.0087 rad, the drum speed of 89.62 rad/s, the feeding concentration of 24.66 wt.%, the feeding flow rate of 2.33×10–4 m3/s, and the feeding time of 90 s. A scanning electron microscopy (SEM) clearly indicated that the pore blockage on the surface of diatoms was cleared out. The variation about the breakage rate of diatom shells was lower than 5% through the pilot purification production line. The characterization of original diatomite and derived products after purification were determined by X-ray diffraction (XRD). The results indicated that the impurity content of purified diatomite was improved significantly.

8

Research on Mechanism Analysis and Elimination Method for the Tufted Carpet Stop Mark

Xu Y., Sun Z., Meng Z, Sun Y.

Fibres & Textiles in Eastern Europe

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2014

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Vol. 22, no. 3 (105)

66--72

EN

The tufted carpet stop mark is an important factor affecting carpet final quality. It is closely related to the change in yarn tension caused by the tufting machine being improperly stopped and the yarn creep properties. The purpose of this paper is to develop a reasonable approach to eliminate the tufted carpet stop mark. Focusing on a typical tufting machine, the tufting equipment system and basic working principle of tufted carpet are briefly described. A yarn path flexing model which integrates yarn feeding parts, yarn guiders and the tufting needle for a typical tufting process is constructed. The yarn tension change is analysed along with the change in the yarn path. A Polypropylene yarn four-component model is used for analysing the relationship between tension and yarn creep properties. The creep property of polypropylene yarn under a certain tension is verified by experiments. According to the yarn tension change in different running positions of the tufting needle, a reasonable method of eliminating the stop mark which stops and restarts the machine in the highest position is put forward. Finally the experimental results prove that the method is effective and feasible.

PL

Ślady zatrzymania pracy maszyn wiążących dywany są ważnym czynnikiem wpływającym na jakość produktu końcowego. Jest to ściśle związane ze zmianą w naprężeniu przędzy spowodowanym przez maszynę wiążącą nieodpowiednio zatrzymaną oraz właściwości pełzania przędzy. Celem pracy było opracowanie metody pozwalającej wyeliminowanie tego zjawiska. W pracy rozważono typową maszynę wiążącą, system wiązania i zasady wiązania dywanów. Opracowano model drogi włókna integrujący elementy prowadzące oraz igły wiążące dla przedstawienia typowego procesu wiązania. Analizowano zmiany naprężenia przędzy wzdłuż jej drogi. Dla przędzy polipropylenowej zastosowano czteroskładnikowy model pozwalający na analizę zależności pomiędzy naprężeniem i pełzaniem przędzy. Właściwości pełzania przędzy polipropylenowej pod określonym naprężeniem zostały zweryfikowane eksperymentalnie. W efekcie opracowano metodę eliminacji śladów zatrzymania, która pozwoliła na efektywną realizację i została sprawdzona doświadczalnie.

9

Protocol Conversion Gateway Design for Fieldbus

Hang H., Sun Z., Li Y., Lou G.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

221--223

EN

The rapid development of the field bus technology, causing the diversity of communication network, not only brings users more options but also a lot of problems. Such as a variety of Profibus coexist and different industries and even enterprise communication standards coexist, sometimes even the production lines in the same shop can adopt different bus standards, therefore, the users will have to face a technology problem that a variety of bus and all kinds of communication protocol products should access the same kind of profibus. It is urgently to be solved to develop protocol conversion interface, making these supporting different profibus interconnect and achieving real data sharing. This paper developed a gateway, which introduces in detail the hardware platform scheme of the gateway, and the idea of software design. The gateway can be applied to different bus equipment connections, which is of great help to implement the network and intelligent automation system.

PL

W artykule przedstawiono schemat hardware’owy i koncepcję sterowania dla bramki w układzie sieci złożonej z wielu szyn Profibus, pozwalającą na sprawną wymianę danych między użytkownikami, korzystającymi z różnych protokołów i standardów. Bramka może być zastosowana w różnych konfiguracjach szyn, co pozwala na sprawną budowę systemów automatyki przemysłowej.

10

A novel stage-based KPLS-PLS monitoring and quality prediction approach for batch processes

Qi Y., Li Y., Sun Z.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

147--150

EN

A novel KPLS-PLS batch monitoring and quality prediction approach based on fuzzy clustering soft-partition is proposed to solve the stage-transition monitoring and prediction problem in multistage batch processes. The proposed method calculates firstly similarity indices between different time-slice data matrices of batch processes, then phase division algorithm is designed by fuzzy clustering based on the similarity index, following by a fuzzy membership grade transition identification step. By setting a series of KPLS and PLS models with time-varying covariance structures for transitions and steady phases, it reflects objectively the diversity of transitional characteristics, capture the nonlinear relationships among process variables of the transition and can monitor and predict batch processes more accurately and efficiently. The superiority of the proposed method is illustrated by applying it to industrial application of fed-batch penicillin fermentation process. The results clearly demonstrate the effectiveness and feasibility of the proposed method.

PL

Zaproponowano nową metodę KPLS ( kernel partial least squers) – PLS monitorowania i przewidywania wieloetapowych procesów wsadowych. Metoda oparta została o klastrowanie rozmyte, pozwala na wykrycie przejść między etapami i dokładniejsze przewidywanie przebiegu procesu przez uniknięcie wpływu nieliniowości. Wyższość proponowanej metody zilustrowano wykorzystując ją do badania przemysłowego procesu fermentacji wsadu pożywki penicyliny.

11

Influence of surface plasmon wave interference on near-field imaging on metal nanostructures with apertured probe

Yang Y., Sun Z.

Optica Applicata

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2013

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Vol. 43, nr 3

615--626

EN

We numerically studied artifact issues on near-field imaging of field intensity on metal nanostruc-tures (isolated ridges and slits in a continuous film) with an apertured probe. It is shown for the latter case that the interaction between neighboring slits via propagating surface plasmon waves (e.g., surface plasmon wave interferences) makes the probe-imaged field intensity highly condi-tional in reflection of the unperturbed field. As surface plasmon behaviors and probe imaging processes are polarization-sensitive and the field components are correlated, a model analysis of the partial field components elucidates their relations, which can help to derive the unperturbed near-field image from the probed one.

12

Hemodynamic impacts of left coronary stenosis : a patient-specific analysis

Chaichana T., Sun Z., Jewkes J.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 3

107--111

EN

This study analyses the hemodynamic variations surrounding stenoses located at the left coronary bifurcation, and their influence on the wall shear stress (WSS) in realistic coronary geometries. Four patients with suspected coronary artery disease were chosen, and coronary models were reconstructed based on high-resolution CT data. The coronary stenoses were observed at the left circumflex and left anterior descending branches, resulting in a lumen narrowing of >50%. Flow analysis was performed using computational fluid dynamics, to simulate the cardiac flow conditions of the realistic individual patient geometry. Blood flow and WSS changes in the left coronary artery were calculated throughout the entire cardiac phases. Our results revealed that the recirculation regions were found at the poststenotic locations. WSS was found to increase at the stenotic positions in all four patients. There is a strong correlation between coronary stenosis and the hemodynamic changes, which are reflected in blood flow pattern and WSS, based on the realistic left coronary geometries.

13

Design and Implementation of a UKF-based SOC Estimator for LiMnO2 Batteries Used on Electric Vehicles

Dai H., Wei X., Sun Z.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 1b

57-63

EN

To ensure safe and reliable battery operations, an accurate battery state of charge (SOC) estimation is critical for the battery systems used in electric vehicles and hybrid electric vehicles because of the arduous operation conditions. This paper presents a SOC estimator designed based on the unscented Kalman filter (UKF), which is very popular in the state estimation in non-linear systems. The dynamic characteristics of the battery are modeled with an equivalent circuit, which is composed of two capacitors, three resistors and a voltage source to simulate the equilibrium open circuit voltage (OCV). To relieve the computation requirement of the original UKF, an efficient implementation using a Cholesky factorization is investigated, and thereby a SR-UKF based SOC estimator is proposed. Experiment results shows that the model proposed can track the dynamic behavior of the battery very well and the UKF-based SOC estimator has a good performance in the state estimation, and a comparison with EKFbased estimator also shows that a better accuracy can be got by the proposed UKF- based estimator.

PL

Artykuł prezentuje system kontroli SOC (state of charge – stan naładowania) baterii używanych w pojazdach elektrycznych. System bazuje na filtrze Kalmana typu UKF. Własności dynamiczne baterii modelowane są przy pomocy odpowiedniego obwodu elektrycznego zastępczego. System może śledzić właściwości dynamiczne baterii i badać jej stan naładowania.

14

Study on power efficiency of vortex beam propagation through an optical system with phase optimization

Wu H., Sheng S., Huang Z., Wang H., Zhao S., Xu X., Sun Z., Xiao R.

Optica Applicata

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2012

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Vol. 42, nr 3

597-611

EN

Beam blocked and truncated by the receiver causes serious power losses in beam uplink propagation in a relay mirror system. We propose a method to improve power efficiency of beam uplink propagation in the relay mirror system by using vortex source and phase optimization. A typical model of beam uplink propagation in the relay mirror system is established. With this model, the principle of the method is theoretically analyzed, and power efficiencies of beam uplink propagation under different conditions are calculated. The calculation results show that power efficiency of beam uplink propagation can be improved from 86.44% to 97.86% by using vortex source and phase optimization. A reduced-scale experiment of beam uplink propagation in the relay mirror system under the "closed-loop" mode is performed, and the experimental results show that power efficiency can be improved from 71.89% to 91.59% by using the vortex source and phase optimization.

15

Energy of intrinsic mode function for gas-liquid flow pattern identification

Sun Z., Gong H.

Metrology and Measurement Systems

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2012

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Vol. 19, nr 4

759-766

EN

Gas-liquid flows abound in a great variety of industrial processes. Correct recognition of the regimes of a gas-liquid flow is one of the most formidable challenges in multiphase flow measurement. Here we put forward a novel approach to the classification of gas-liquid flow patterns. In this method a flow-pattern map is constructed based on the average energy of intrinsic mode function and the volumetric void fraction of gas-liquid mixture. The intrinsic mode function is extracted from the pressure fluctuation across a bluff body using the empirical mode decomposition technique. Experiments adopting air and water as the working fluids are conducted in the bubble, plug, slug, and annular flow patterns at ambient temperature and atmospheric pressure. Verification tests indicate that the identification rate of the flow-pattern map developed exceeds 90%. This approach is appropriate for the gas-liquid flow pattern identification in practical applications.

16

Design and performance of the converging-diverging vortex flowmeter

Sun Z.

Metrology and Measurement Systems

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2011

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Vol. 18, nr 1

129-136

EN

The converging-diverging structure is introduced to extend the lower limit of measurement of vortex flowmeters. As a compact device, the converging-diverging vortex flowmeter is proposed and designed, and its performance is studied experimentally. It is found that, first of all, an up to 51% extension of the lower measurement limit can be realized through the converging-diverging structure, compared with conventional vortex flowmeters; second, the converging-diverging vortex flowmeter with a trapezoidal bluff body has a larger Strouhal number and smaller pressure loss. The results suggest that the converging-diverging vortex flowmeter provides an alternative device especially suitable for the measurement of low-velocity fluids.

17

On board condition monitoring of feed axes by signal decomposition for machines with ball screw drives

Maier D., Sun Z.

Journal of Machine Engineering

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2009

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Vol. 9, No. 3

42--63

EN

In order to establish a condition monitoring system to detect wear of the mechanical components of feed drives with ball screws a measuring and data evaluation method has been established. In order to keep the costs down, boundary condition is to use the machines own functionalities only (On Board Diagnosis). At present, most of wear detecting methods use vibration analysis. Here, a signal analysis method is presented that may well complement established methods of vibration analysis. The publication presents a method to exploit positioning data to detect wear of a ball screw drive exemplarily that is run under real conditions. The presented method is partially derived from wear detection methods of roller bearings and may also be adapted for other parts such as linear guides.

18

Beam shaping based on intermediate zone diffraction of a micro-aperture

Zeng D., Sun Z.

Optica Applicata

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2008

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Vol. 38, nr 3

511-517

EN

We analyze optical diffraction of a micro-aperture (slit or hole) in a metal screen in the intermediate zone and report its application for beam focusing and collimating in micro-optics. Both finite-difference time-domain simulations and Rayleigh-Sommerfeld diffraction formula were applied to calculate the intermediate-zone diffraction patterns. It is shown that, by controlling the aperture size, the focal length and depth can be adjusted in a very wide range, from subwavelength to tens of wavelengths, while the focal width maintains in an order of wavelength.

19

Effect of Ni addition on the microstructures of melt-spun CuCr ribbons

Yu M., Wang Y., Wang Y., Sun Z.

Materials Science Poland

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2008

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Vol. 26, No. 3

675--680

EN

The microstructures and resistivities of melt-spun Cu75Cr25 and Cu(75.x)Cr25Nix (x = 1 or 3 wt. %) ribbons were studied. The size of the Cr-rich phase from liquid phase separation in the Cu75Cr25 microstructure can be decreased from the micrometer-scale to about 250 nm by using melt spinning. After annealing at 600 ° C for 3 h, the resistivity of Cu75Cr25 ribbon can meet the needs of contact. On the melt-spun base, alloying by Ni could further decrease the size of the Cr-rich phase from 250 nm to about 150 nm. However, when the Ni content is higher than or equal to 3%, the resistivity of annealed Cu75. xCr25Nix (x ≥ 3) ribbons is too high to be used by the medium-voltage vacuum interrupters. For nanograined CuCr alloys, its lower arc chopping current is advantageous to the use of contact and the circuitry protect, its long arc trace route and high velocity of spot direction motion could mitigate the partial ablate of cathode surface and the lifetime of contact could be prolonged.

20

The solidification of CuCr alloys under various cooling rates

Wang Y., Song X., Sun Z., Zhou X., Guo J.

Materials Science Poland

|

2007

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Vol. 25, No. 1

199--207

EN

The paper focuses on the solidification especially on the liquid phase separation of Cu-35 at. % Cr alloys under various cooling rates. When the solidification temperature is below the liquidus and above the spinodal temperature, solidification runs normally, with the growth of primary Cr-rich dendrites. When the solidification temperature is below the spinodal temperature, liquid phase separation should occur through the solidification process and the primary Cr-rich phase has a special nodular structure under an appropriate cooling rate. Large Cr-rich particles obtained from liquid phase separation can grow by absorbing smaller ones via the transfer of matter. Furthermore, some particles collide with each other, mutually losing surface energy by joining to form a single particle. The size of the Cr-rich particles obtained from liquid phase separation decreases with increasing cooling rate. Using thermodynamic calculations and referring to literature data, the viewpoints on liquid phase separation are systematized and applied to the CuCr system. Liquid phase separation in an undercooled liquid is not advantageous in refining the microstructure of alloys and should be restricted.