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1

Study on the design of container highway and railway automatic transfer vehicle in ocean port

Dong L., Liu G., Ye X., Wang W.

Polish Maritime Research

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2018

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S 3

5--12

EN

To realize “seamless” connection of ocean port container multimodal transport, efficiently carry out “door-to-door” transport of ocean port containers and overcome the shortcomings of existing highway and railway vehicles, this study takes the standard for heavy-duty container vehicles in TB1335-1996 Railway Vehicle Strength Design and Test Identification Code as the design basis and designs a new ocean port container transport vehicle in combination with automatic guidance technology. This study innovatively designs the automatic lifting system of the bogie and the docking part of the vehicle, introduces the automatic guidance technology and the remote-control technology to optimize the car body structure, and uses the SAP software to carry out the finite element analysis of the car body load capacity and Flexsim software to carry out the simulation analysis on the operation of vehicles. The designed transfer vehicle can improve the transfer efficiency of ocean port containers, reduce the transit time of field and station equipment and container transport links, and improve the level of multimodal transport and comprehensive economic benefits.

2

An optimization approach to the intermodal transportation network in fruit cold chain, considering cost, quality degradation and carbon dioxide footprint

Ma Q., Wang W., Peng Y., Song X.

Polish Maritime Research

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2018

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nr 1

61--69

EN

This model optimizes port hinterland intermodal refrigerated container flows , considering both cost and quality degradation, which is distinctive from the previous literature content in a way that it quantifies the influence of carbon dioxide (CO2) emission in different setting temperature on intermodal network planning. The primary contribution of this paper is that the model is beneficial not only to shippers and customers for the novel service design, but also offer , for policy-makers of the government, insights to develop inland transport infrastructures in consideration of intermodal transportation. The majority of models of multimodal system have been established with an objective of cost minimization for normal commodities. As the food quality is possible to be influenced by varying duration time required for the storage and transportation, and transportation accompanied with refrigeration producing more CO2 emission, this paper aims to address cost minimization and quality degradation minimization within the constraint of CO2 footprint. To achieve this aim, we put the quality degradation model in a mixed-integer linear programming model used for intermodal network planning for cold chain. The example of Dalian Port and Yingkou Port offer insight into trade-offs between transportation temperature and transport mode considering CO2 footprint. Furthermore, the model can offer a useful reference for other regions with the demand for different imported food, which requires an uninterrupted cold chain during the transportation and storage.

3

Micro-FTIR analysis to study the change in surface chemistry after addition of collectors and their effect on coal hydrophobicity

Wang W., Kumar A., Holuszko M. E., Mastalerz M.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 4

1292--1302

EN

In this study, the micro-FTIR analysis was used to investigate in-situ surface properties of coal, and was directly correlated to coal hydrophobicity, as measured by the contact angle before and after the addition of collectors, to understand their suitability for flotation. Three different collectors, diesel, pine needle oil and dodecyl trimethyl ammonium bromide (DTAB) were tested. The micro-FTIR technique provided a semi-quantitative analysis of functional groups present on the coal surface exactly where the contact angle was measured and provided a visualization of collector adsorption on specific areas of coal and associated changes in coal surface properties. This analysis could lead to a smarter way of using process design in terms of reagent selection for coal flotation to obtain a product of desired petrographic composition, which would especially be useful for coking coals. This study presents a work in progress for developing a procedure for a quick pre-selection of collectors for coal flotation based on coal surface properties.

4

Moving-aperture-based three-dimensional micro-measurement system

Fan S., Yu M., Jiang G., Wang Y., Wang W., Li W.

Optica Applicata

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2018

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Vol. 48, nr 4

533--547

EN

To overcome the depth-of-field limitation of an optical microscope image, a three-dimensional measurement method with a superior depth-of-field is proposed. In the proposed method, light-field information of different angles is obtained by moving the aperture and the three-dimensional scene is reconstructed by using a computational reconstruction technology. First, stereo matching of different aperture position images is performed to obtain the multi-aperture imaging deviation. The focal plane moving distance is thereby estimated. Then, the relational expression between the image coordinates and the focal plane moving distance is determined according to the image coordinates. Two dimensional coordinates of the space point are obtained by the expression coefficients. Finally, the depth coordinates are computed, and three-dimensional reconstruction of the spatial points is completed. Experiments of three-dimensional measurements of the calibration board with different angles and circuit boards are conducted. The results show that the maximum error of the distance measurement is controlled into 0.84%, and the maximum angle measurement error is controlled into 4.56%.

5

Unravelling the Effect of Anthraquinone Metal Salts as Wide-range Plateau Catalysts to Enhance the Combustion Properties of Solid Propellants

Wang Y., Yan Q.-L., An T., Chen B., Ji Y.-P., Wang W., Zhao F.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 2

376--390

EN

Novel lead and copper salts based on anthraquinone, including 1,8-dihydroxyanthraquinone,1,4,5,8-tetrahydroxyanthraquinone and 1,8-dihydroxy-4,5-dinitroanthraquinone, were prepared and characterized by Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA), and X-ray fluorescence (XRF). The catalytic effects of these compounds on the decomposition of nitrocellulose (NC) and on the combustion properties of double-base (DB) and composite modified double-base (CMDB) propellants were comprehensively investigated. The results demonstrated that the burning rate is significantly increased (by 200%) in the lower pressure range (2-6 MPa) as compared to the control systems without added anthraquinone-based salts. Concurrently, the pressure exponents (n) were obviously lower, exhibiting a “wide-range plateau” combustion phenomenon in the middle-pressure region. Specifically, for the DB propellants such a plateau region extended from 10 MPa to 16 MPa for n equal to 0.10, from 10 MPa to 18 MPa for n equal to 0.11 and from 8 MPa to 18 MPa when n is 0.05. In the case of RDX-CMDB propellants, the plateau was found to be in the range 6-18 MPa, with n in the range 0.16-0.27, depending on the type of catalyst, in contrast to the reference CMDB sample, which was characterized by n equal to 0.7 for the same pressure range.

6

System and Method for Simultaneous Measurement of Nitrogen Content and Uniformity of Nitration of Nitrocellulose

Liu Y., Shao Z., Wang W., Li W., Lv Y., Sun J.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 4

554--571

EN

Nitrocellulose (NC) is a common, commercially available, cellulosederived material and has been functionalized and widely applied in microfluidic technology, immunoassays and biochemical analyses. However, existing testing parameters always fail to completely and accurately reflect its inherent quality. In this study, we have designed and assembled a novel automatic polarizing microscope test system (PMTS) to scientifically test the nitrogen content and uniformity of nitration of NC based on the chromogenic principle of a polarization microscope. The advantages of this system are: (i) the PMTS requires less sample (only a few micrograms); (ii) the test period is shorter and the results can be obtained within 20 min; (iii) the method belongs to the nondestructive testing group, and the NC sample is not burned, dissolved, or damaged; and (iv) this method has increased accuracy, and the deviation of the nitrogen content is less than ±0.05%. The properties of various NC samples prepared by different nitricsulfuric acid systems from raw materials with diverse maturities were determined via PMTS. Five NC samples with different nitrogen contents (10.9%, 11.5%, 11.8%, 12.6% and 13.5%) were tested, and the variance of the corresponding uniformity of nitration of these samples were 3.17, 1.61, 1.15, 1.76, and 2.83. The uniformity of nitration initially decreased and then increased with increasing nitrogen content, and the best uniformity of nitration appeared at a nitrogen content of 12%. We also found that fibre maturity has a positive effect on the uniformity of nitration. This testing device and method, with its cost-effectiveness and field-portability, can significantly improve the accuracy of nitration content and uniformity, and has an important value in practical applications.

7

Synthesis, Characterization and Compatibility Studies of Poly(DFAMO/NIMMO) with Propellant and PBX Ingredients

Li H., Yang Y., Pan J., Wang W., Pan R., Zhu W.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

85--99

EN

Oxetane-based polymers substituted with difluoroamino groups can be used as energetic binders in propellants and polymer-bonded explosives (PBXs). As a novel candidate, poly(3-difluoroaminomethyl-3-methyloxetane/3-nitratomethyl-3-methyloxetane) (PDN) was synthesized and its structure was established. Thermogravimetry (TG) and differential scanning calorimetry (DSC) were employed to investigate its thermal decomposition behaviour. The compatibility between PDN and some common ingredients of propellants and PBXs was evaluated by the DSC method. PDN with good thermal stability was synthesized via a cationic solution polymerization process. Additionally, it has improved compatibility with cyclotetramethylenetetranitramine (HMX), carbon black (C.B.) and lead carbonate (PbCO3) compared with homopoly(3-difluoroaminomethyl-3-methyloxetane) (PDFAMO). PDN could be used as a promising difluoroamino energetic binder in the future.

8

Comparative Theoretical Investigation on Energetic Substituted Furazanyl Ethers

Liu N., Wang K., Shu Y., Zeman S., Wang B., Wang W.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

47--71

EN

Furazanyl ether has great potential to be an important candidate as a casting explosive and energetic plasticizer. The density functional theory (DFT) method was used to investigate the heats of formation (HOFs), molecular stability, detonation performance and melting point of a series of substituted furazanyl ethers at B3LYP/6-311G(d,p) level. The results show that the introduction of –N3 or –N(O)=N– groups significantly improves the HOFs values of the derivatives. The bond dissociation energies (BDEs) were analyzed, showing that the N–O bond in the furazan ring is the weakest for most compounds and the ring is vulnerable to cleavage in thermal decomposition. The calculation of density, detonation velocities and detonation pressures suggests that the substitution of –NF2, –CF(NO2)2, furoxan or –N(O)=N– group is an effective method for enhancing their detonation performance. The melting points were determined according to the variation of specific heat capacity, and good estimates were obtained in comparison with the available experimental data. Taking into account the detonation performance and melting point, four compounds are favoured for application in melt cast explosive or energetic plasticizers.

9

Improving Waveform Inversion using Modified Interferometric Imaging Condition

Guo X., Liu H., Shi Y., Wang W., Zhang Z.

Acta Geophysica

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2018

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Vol. 66, no. 1

71--80

EN

Similar to the reverse-time migration, full waveform inversion in the time domain is a memory-intensive processing method. The computational storage size for waveform inversion mainly depends on the model size and time recording length. In general, 3D and 4D data volumes need to be saved for 2D and 3D waveform inversion gradient calculations, respectively. Even the boundary region wavefield-saving strategy creates a huge storage demand. Using the last two slices of the wavefield to reconstruct wavefields at other moments through the random boundary, avoids the need to store a large number of wavefields; however, traditional random boundary method is less effective at low frequencies. In this study, we follow a new random boundary designed to regenerate random velocity anomalies in the boundary region for each shot of each iteration. The results obtained using the random boundary condition in less illuminated areas are more seriously affected by random scattering than other areas due to the lack of coverage. In this paper, we have replaced direct correlation for computing the waveform inversion gradient by modified interferometric imaging, which enhances the continuity of the imaging path and reduces noise interference. The new imaging condition is a weighted average of extended imaging gathers can be directly used in the gradient computation. In this process, we have not changed the objective function, and the role of the imaging condition is similar to regularization. The window size for the modified interferometric imaging condition-based waveform inversion plays an important role in this process. The numerical examples show that the proposed method significantly enhances waveform inversion performance.

10

Identification of multiple constituents in shuganjieyu capsule and rat plasma after oral administration by ultra-performance liquid chromatography coupled with electrospray ionization and ion trap mass spectrometry

Xiao Y. C., Liu L. T., Bian J. J., Yan C. Q., Ye L., Zhao M. X., Huang Q. S., Wang W., Liang K., Shi Z. F., Ke X.

Acta Chromatographica

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2018

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Vol. 30, no. 2

95--102

EN

Shuganjieyu (SGJY) capsule is a classical formula widely used in Chinese clinical application. In this paper, an ultra-performance liquid chromatography coupled with electrospray ionization and ion trap mass spectrometry has been established to separate and identify the chemical constituents of SGJY and the multiple constituents of SGJY in rats. The chromatographic separation was performed on a C18 RRHD column (150 × 2.1 mm, 1.8 μm), while 0.1% formic acid–water and 0.1% formic acid–acetonitrile was used as mobile phase. Mass spectral data were acquired in both positive and negative modes. On the basis of the characteristic retention time (Rt) and mass spectral data with those of reference standards and relevant references, 73 constituents from the SGJY and 15 ingredients including 10 original constituents and 5 metabolites from the rat plasma after oral administration of SGJY were identified or tentatively characterized. This study provided helpful chemical information for further pharmacology and active mechanism research on SGJY.

11

Different Patterns of Changes in Foliar Carbon Isotope Composition Along Altitude

He Z., Zhan S., Wang W., Hu L., Wu S.

Polish Journal of Ecology

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2017

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Vol. 65, nr 2

227--235

EN

Three types of alpine plant species, Carex montis-everestii, Quercus aquifolioides and Stipa capillacea, along an altitudinal gradient of 3005-5025 m on the Tibetan Plateau, were chosen to test the generality of the hypothesis that foliar carbon isotope composition (δ13C) of C3 plants increases significantly with altitude and to determine climate drivers shaping its altitudinal pattern. Temperature and relative humidity showed significantly negative correlations with altitude; however, precipitation and soil water potential remained unchanged with altitude. Foliar δ13C of C. montis-everestii, Q. aquifolioides, S. capillacea alone or combined together did not significantly increase with altitude, which does not support the leading hypothesis of increased foliar δ13C with altitude. There was no difference in foliar δ13C among all three species. Multi-factor correlation analyses showed that temperature, precipitation and relative humidity alone did not affect foliar δ13C of C. montis-everestii and S. capillacea, but conferred significant effects on foliar δ13C of Q. aquifolioides.

12

Synthesis and Characterization of 1-(1-chlorocyclopropyl)-2-(1,2,4-triazol-1-yl)ethan-1-one

Ji H., Niu Y., Liu D., Wang W., Dai C.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 1

41--47

EN

A simple and efficient method to prepare 1-(1-chlorocyclopropyl)-2-(1,2,4-triazol-1-yl)ethan-1-one via nucleophilic substitution of 2-chloro-1-(1-chlorocyclopropyl)ethanone and 1,2,4-triazole is described. The title compound is the key intermediate required for the synthesis of prothioconazole, a promising agricultural fungicide. By exploring changes in the reaction time, temperature, ratio of starting reagents, acid binding agent, and the nature of phase transfer catalyst, the reaction conditions could be optimized to afford the desired N-alkylated material in near-quantitative yield. The ultimate yield of the product after recrystallization was 93%, with a purity of 99% based on its characterization by Gas Chromatography-Mass Spectrometer (GC-MS), Fourier Transform infrared spectroscopy (IR), Proton Magnetic Resonance (1H NMR), and Carbon-13 Nuclear Magnetic Resonance (13C NMR). The synthetic process is suitable for industrial application, with the advantages of high yield and facile preparation under mild operating conditions.

13

Evaluation of sodium petroleum sulfonates with different molecular weights for flotation of kyanite ore

Chen B. Z., Gao H., Li Y., Jin J., Ren Z., Wang W.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

956--968

EN

The flotation performance of sodium petroleum sulfonates with different molecular weights was evaluated for flotation of a kyanite ore, by investigating valuable mineral recovery-grade, flotation kinetics and gangue entrainment. The results indicated that the higher molecular weight of agent, the higher final cumulative kyanite recovery was, with the maximum value of 72% being obtained with KY-3 with the molecular weight of 438. The final cumulative kyanite grade initially increased, and then decreased with the molecular weight increasing. In other words, the maximum final cumulative kyanite grade (i.e. 89.05%) was obtained with KY-2 with the molecular weight of 392. The kyanite flotation kinetics followed the first order kinetics well, while the modified flotation rate constant showed a decreasing trend after the initial increase as the molecular weight increased. In addition, the overall entrainment degree decreased with decreasing molecular weight of sodium petroleum sulfonates. The use of KY-2 in kyanite flotation was an attractive option in comparison with KY-1 and KY-3.

14

Improvement of accuracy of simple methods for design and analysis of a blazed phase grating microstructure

Wang W., Jing X., Zhao J., Li Y., Tian Y.

Optica Applicata

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2017

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Vol. 47, nr 2

183--198

EN

In order to precisely analyze and design the transmittance characteristics of a blazed grating, the validity of both the scalar diffraction theory and the effective medium theory is quantitatively demonstrated. By making a comparison of diffraction efficiencies calculated by the two simplified methods and Fourier modal method, the accuracy can be obtained. It is found that when the normalized period is more than three wavelengths of the incident light, the scalar diffraction theory is useful to calculate the transmittance of the blazed grating within the error of less than 3%. The validity of the scalar diffraction theory increases when the normalized period increases. Importantly, by considering the Fresnel reflection effect, the validity of scalar diffraction theory can be significantly enhanced. Furthermore, when no higher-order diffraction waves appear and only zeroth order diffraction wave propagates, the effective medium theory is accurate to compute the diffraction efficiency within the difference of less than 1% between the zeroth order effective medium theory and Fourier modal method. The polarization characteristics of the validity of effective medium theory are also quantitatively demonstrated. The validity of the two simplified theories is dependent on not only the normalized period of surface microstructure but also the normalized groove depth.

15

Simultaneous determination of eleven alkaloids in Corydalis decumbens by HPLC with diode-array detection

Gu G. H., Yang D. J., Wang S. Y., Zeng W., Wang W., Yuan J. S.

Acta Chromatographica

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2017

|

Vol. 29, no. 1

121--134

EN

A high-performance liquid chromatography—diode-array detection method was developed and validated to determine simultaneously eleven major alkaloids in Corydalis decumbens (Thunb.) Pers. The alkaloids detected were corlumidine, protopine, coptisine, tetrahydrojatrorrhizine, palmatine, berberine, sanguinarine, papaverine hydrochloride, tetrahydropalmatine, bicuculline, and corydaline. Chromatographic separation was achieved using a C-18 column with a mobile phase composed of A (0.2% acetic acid solution, adjusted with triethylamine to pH 5.0) and B (acetonitrile), with stepwise gradient elution. Ultraviolet diode-array detection was used; chromatograms were examined at the wavelength of 280 nm. The regression equations showed a good linear relationship between the peak area of each marker and concentration (r = 0.9994–0.9999). The recovery values ranged between 93.66% and 100.54%. The method was fully validated with respect to detection and quantification limits, precision, reproducibility, and accuracy. The described high-performance liquid chromatography (HPLC) method was successfully used for the differentiation and quantification of the eleven major alkaloids in C. decumbens (Thunb.) Pers. and can be considered an effective procedure for the analyses of this important class of natural compounds.

16

Experimental and mathematical investigations on unconfined compressive behaviour of costal soft soil under complicated freezing processes

Wang W., Li N., Zhang F., Zhou A., Chi S.

Polish Maritime Research

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2016

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nr 4

112--116

EN

In order to properly understand the effect of freezing-thawing circle (FTC) to mechanical behavior of costal soft soil (CSS), unconfined compressive test is conducted. Six kind FTC times are designed from zero to five. The tested data show that: (1) unconfined compressive strength of CCS decreases nonlinearly with more FTC, and the strength after five FTC times becomes about 22% of its original strength without any freezing-thawing experience; (2) stressstrain curves of all unconfined compressive samples can be well fitted by three-parameter hyperbolic model; (3) and relationship between two parameters and FTC times can be fitted by exponent function, while another parameter can be considered as 0.95. Consequently, one composite hyperbolic- exponent empirical formula is established in order to describe freezing-thawing-dependent stress-strain behavior of CSS. Finally, good agreements have been found between tested dada and simulated results.

17

Prediction of the Distribution of Alpine Tree Species Under Climate Change Scenarios: Larix chinensis in Taibai Mountain (China)

Zhao X., Meng H., Wang W., Yan B.

Polish Journal of Ecology

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2016

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Vol. 64, nr 2

200--212

EN

Larix chinensis, an endangered and endemic alpine tree, occurs on Mt. Taibai in the Qinling Mountains, China. The extreme sensitivity of this species to climate change makes predicting its future distribution important. Using high-resolution remote-sensing imagery, and the Maxent model, we analysed the current distribution and forecast future distribution of L. chinensis under two climate change scenarios, IPCC A2 and IPCC B2. The results showed that three dominant climatic factors influenced the geographic distribution of L. chinensis: mean annual temperature, mean temperature of the coldest quarter, and precipitation of wettest month. Currently, L. chinensis mainly concentrated at 3100 m and covers an area of 53.52 km2. The population on the southern slope covers approximately twice the area of that on the northern slope; the model simulations indicated that the area of suitable habitat would decrease continually under two climate change scenarios, A2 and B2; the decrease was more obvious in scenario A2, and the range in scenario A2 covers approximately twice the area of that in scenario B2. Under both scenarios, L. chinensis would first be extirpated at lower elevations, and the suitable habitat of this species would move to higher elevations in the Taibai Mountains.

18

Effects of Abietinella abietina Extracts on the Germination and Seedling Emergence of Picea crassifolia: Results of Greenhouse Experiments

Wang Q., Zhao C., Gao Y., Gao C., Qiao Y., Xie H., Wang W., Yuan L., Liu J., Ma W., Li W.

Polish Journal of Ecology

|

2016

|

Vol. 64, nr 3

357--368

EN

Moss cushion plays an important role in recruitment of vascular plants. In this study, we examined the effects of water soluble extracts (WSE) of Abietinella abietina on germination of Qinghai spruce (Picea crassifolia) and the effects of moss substrates (A. abietina) on seedling emergence of P. crassifolia in two greenhouse experiments. We found that the WSE of moss affected germination of P. crassifolia in two ways: (1) the WSE reducing the risk of fungal infection to the seeds, improve the germination rate; and (2) the WSE affects germination by its concentration, that is, low concentrations of WSE (i.e., 0.5 mg ml-1 and 5 mg ml-1) stimulate, while high concentrations (i.e., 50 mg ml-1) inhibit it. In seedling emergence experiments, we detected that the moss substrates (both thick and thin mosses) facilitate the emergence of P. crassifolia in dry and intermediate moisture conditions, but inhibit it in moist conditions. In bare soil, the P. crassifolia emergence was also controlled by moisture conditions; the highest (60%) and the lowest (35%) emergence occurred in the moist conditions and dry conditions, respectively. We also found that P. crassifolia seedlings were thinner and taller, but their number higher in moss cushion than in bare soil. Thus we conclude that there is nurse effect of A. abietina cushion on recruitment of P. crassifolia in both dry and intermediate moisture conditions.

19

Converged ultra-wideband and multi-level wired signal downstream transport over single wavelength in wavelength-division multiplexing passive optical network

Ma H, Wang F., Wang W., Zhang X, Yu Q.

Optica Applicata

|

2015

|

Vol. 45, nr 4

433--445

EN

Simultaneous providing services of ultra-wideband and wired signal over single wavelength can greatly decrease the complexity and reduce the costs of a wavelength-division multiplexing passive optical network. However, ultra-wideband signal occupies the spectrum range from 3.1 to 10.6 GHz, and a narrow idle frequency band (from 0 to 3.1 GHz) could be employed to transport wired signal with a limited rate. In this paper, we proposed a scheme to simultaneously provide ultra-wideband and wired services, in which the information rate of the wired signal is enhanced by employing a multi-level amplitude switch keying signal in the idle frequency band formed by ultra-wideband signal. In comparison with other advanced modulation formats used for wavelength-division multiplexing passive optical networks such as orthogonal frequency division multiplexing, multi-level amplitude switch keying signal can be easily received by using intensity modulation direct detection, which will greatly reduce the cost of end-users. Especially, if a multi-band ultra-wideband signal is substituted for the direct-sequence ultra-wideband signal, the available spectrum range to transport wired signal will be easily extended to 5 GHz as multi-band ultra-wideband signal has a narrower spectrum width and flexible center frequency, so 4-amplitude switch keying signal with a rate of 5 Gbaud will achieve an information rate of 10 Gbit/s.

20

An integrated production and delay-time based preventive maintenance planning model for a multi-product production system

Liu X., Wang W., Peng R.

Eksploatacja i Niezawodność

|

2015

|

Vol. 17, no. 2

215--221

EN

This paper integrates preventive maintenance and medium-term tactical production planning in a multi-product production system. In such a system, a set of products needs to be produced in lots during a specified finite planning horizon. Preventive maintenance is carried out periodically at the end of some production periods and corrective maintenance is always performed at failures. The system’s available production capacity can be affected by maintenance, since both planned preventive maintenance and unplanned corrective maintenance result in downtime loss during the planning horizon. In addition to the time used for preventive and corrective maintenance, our model considers the setup time and the product quality, as these are affected by the defects and failures of the system. Procedures are proposed to identify the optimal production plan and preventive maintenance policy simultaneously. Our objective is to minimize the sum of maintenance, production, inventory, setup, backorder costs and the costs of unqualified products within the planning horizon. A real case from a steel factory is presented to illustrate the model.

PL

W niniejszej pracy zintegrowano proces konserwacji zapobiegawczej z procesem średnioterminowego taktycznego planowania produkcji w odniesieniu do systemu produkcji wieloasortymentowej. W takim systemie, zestaw wyrobów jest produkowany partiami w określonym, skończonym horyzoncie planowania. Konserwacja zapobiegawcza prowadzona jest okresowo pod koniec wybranych okresów produkcyjnych, natomiast w przypadku wystąpienia uszkodzenia wykonuje się konserwację korygującą. Konserwacja może mieć wpływ na dostępne moce produkcyjne systemu, jako że zarówno planowana konserwacja prewencyjna jak i nieplanowana konserwacja korygująca powodują straty związane z przestojem urządzeń w danym horyzoncie planowania. Oprócz czasu potrzebnego na konserwację zapobiegawczą i korygującą, nasz model uwzględnia czas konfiguracji urządzeń oraz jakość produktów, ponieważ one również zależą od defektów i awarii systemu. Zaproponowano procedury, które pozwalają na jednoczesne określenie optymalnego planu produkcji i optymalnej strategii konserwacji prewencyjnej. Naszym celem jest minimalizacja sumy kosztów konserwacji, produkcji, zapasów, konfiguracji urządzeń oraz zamówień oczekujących a także kosztów produktów, które nie zostały zakwalifikowane do wprowadzenia do obrotu w danym horyzoncie planowania. Model zilustrowano na przykładzie rzeczywistego przypadku z fabryki stali.