Wyniki wyszukiwania

1

Adaptive sliding mode control for ship autopilot with speed keeping

100%

Liu Z.

Polish Maritime Research

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2018

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tom 25

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nr 4

The paper addresses an important issue in surface vessel motion control practice that the ship dynamics and sailing performance can be affected by speed loss. The vessel speed is significantly decreased by the added resistance generated by waves. An adaptive sliding mode course keeping control design is proposed which takes into account uncertain ship dynamics caused by forward speed variations, while avoiding performance compromises under changing operating and environmental conditions. The sliding mode control provides robust performance for time-varying wave disturbances and time-varying changes in ship parameters and actuator dynamics. After combining the unknown but bounded system uncertainties, the design of the adaptation law is obtained which is based on the Lyapunov’s direct method. Simulations on a ship with two rudders illustrate the effectiveness of the proposed solution

2

Pre-filtered backstepping control for underactuated ship path following

100%

Liu Z.

Polish Maritime Research

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2019

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tom 26

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nr 2

Robust path following control for underactuated surface ships is an important issue in marine control practice. This paper aims to improve the robustness of the close-loop system with model uncertainties and time-varying disturbances. A practical adaptive backstepping control scheme with a pre-filter is proposed to force a surface vessel to track the predefined path generated by the virtual ship. Based on the Lyapunov stability theorem, this algorithm can guarantee all error signals in the overall system to be uniformly ultimately bounded, and it can be implemented without exact knowledge of the nonlinear damping structure and environmental disturbances. The proposed pre-filter can smooth the commanded heading order and obtain a better performance of the waypoint-based navigation control system. Two simulation cases are drawn to illustrate the validity of the proposed control strategy

3

Ocena wartosci hodowlanej bydla mlecznego w Niemczech

75%

Liu Z.

Przegląd Hodowlany

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2003

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tom 71

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nr 11

3-4

4

Enhancing photosynthetic CO2 use efficiency in rice: approaches and challenges

63%

Liu Z., Sun N.

Acta Physiologiae Plantarum

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2013

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tom 35

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nr 04

It is estimated that 925 million people mainly in developing countries suffer from malnutrition due to food shortage. This situation will deteriorate as world population will reach 9 billion by 2050. It is obvious that current rate of increase in crop yields is not sufficient to solve the problem of food security worldwide, especially in Asia, where at least 50 % increase in rice yield is needed to satisfy the increasing population. Depending on advanced development of modern biotechnology, several strategies have been provided for ‘supercharging’ photosynthesis to increase rice yield. In this review, we updated four major approaches: namely improving the performance of ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), establishment of photorespiratory bypass, installing single-cell and two-celled C4 photosynthesis. The first approach aimed at direct manipulation of Rubisco for more efficient catalytic character by directed molecular evolution. The second approach focused on reducing the loss of photorespiratory CO2 by direct manipulation of photorespiratory pathway. The last two concentrated on introduction of C4 pathway into rice, based on the observation that the efficiency of C4 photosynthesis is 50 % higher than that of C3 photosynthesis.

5

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Modelling test day data from dairy cattle

63%

Szyda J., Liu Z.

Journal of Applied Genetics

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1999

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tom 40

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nr 2

6

Nonlinear drift of the spring gravimeter caused by air pressure from the Kunming GS15 gravimeters

51%

Wei J., Shen W., Li H., Liu Z.

Polish Maritime Research

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2016

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tom 23

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nr Special Issue S1

In order to monitor and correct the meteorological factors of the spring gravity meter, the characteristics of the time varying gravity changes caused by meteorological factors were analyzed. Kunming GS15 gravity meter from 2007 continuous gravity observation has been carried out with the sampling rate of the pressure observation. In this study, we first compare the effects of 4 types of gravity meter and 3 different types of stations on the gravity observed seasonal gravity signals. It is indicated that the observed seasonal gravity signal of the cave is only 1/10, and there is a constant temperature and constant pressure device. Compared with the same time, the gravity signal of the gravity signal is about 100 times smaller. The influence of the pressure load of the gravity meter is tested by using the theory of pressure. The results show that only the actual value of 2cpd - 3cpd pressure load varies from -0.395 to -0.280×10-8ms-2 , and the 1cpd to 1 cpm periodic partial type gravity meter is also in accordance with the law of gravity and air pressure. And with the characteristics of time lag. In this paper, the nonlinear zero drift parameters of the linear regression model with time lag and the time series of the GS15 gravity meter are used to simulate the nonlinear zero drift parameters of the gravity meter. The results show that the gravity signal contains time lag 35 hours, and the air pressure admittance is 0.8 × 10-8ms-2/mbar. The correlation can reach 79%. The gravity changes signal and satellite gravity as well as the gravity water load signal of the land water model are the same as the gravity water load signal in the autumn as the minimum value, and the seasonal variation of the maximum value of gravity in summer

7

Study of bioretention system on heavy-metal removal effect

51%

Liu Z., Li J., Li Y., Li W.

Polish Journal of Environmental Studies

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2018

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tom 27

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nr 1

Bioretention is a typical low-impact development (LID) technology. This work used four different filler combinations of bioretention tank pilot test devices. Experiments on influence factors and intermittent operation were conducted. A continuous-run experiment was also performed to determine the purification ability of bioretention system on heavy metals. Results showed that the removal efficiency of heavy metals by fly ash tank was the most efficient, with a removal rate reaching 85.57%. The removal effect on highinfluent concentrations in filter was better than that in low-influent concentrations. With increased rainfall time intervals (antecedent dry time), heavy-metal removal efficiency improved. Temperature did not affect the removal efficiency of heavy metals on the whole based on the long duration of intermittent operation experiments. Moreover, the effluent heavy-metal concentration presented a descending trend during each simulation rainfall runoff event. During continuous operation test, heavy metals did not reach the exhaustion point in the experimental tanks, while the effluent concentration increased with increased water volume. According to PLS regression analysis, rainfall time interval was the most important factor affecting Zn removal rate, followed by filler characteristics, influent volume, and influent concentration.

8

Soil aggregate size distribution and total organic carbon in intra-aggregate fractions as affected by addition of biochar and organic amendments

51%

Odugbenro G. O., Liu Z., Sun Y.

Polish Journal of Soil Science

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2020

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tom 53

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nr 1

9

Dissecting an interplay between genomic and pedigree sources of information to estimate breeding values for milk yield in Polish Holstein-Friesian dairy cattle in a one-step approach based on a random regression test day model

51%

Suchocki T., Liu Z., Zarnecki A., Szyda J.

Animal Science Papers and Reports

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2017

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tom 35

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nr 2

In the future an approach incorporating cows’ measured phenotypes and marker genotypes of cows and bulls within a single model can be applied. The most important advantage of such a model is the simultaneous use of pedigree and marker-based genomic relationship data. Such a solution allows the use of both genotyped and non-genotyped animals in the prediction procedure. This pilot study is aimed towards implementation of a one-step approach in a random regression test day model context for the Polish Holstein Friesian population, considering various ways of adjusting the relationship matrix. Data consisted of 890 animals (10 genotyped bulls, 100 cows with phenotypic data and 780 ancestors without genotypes or phenotypes). Random regression test day models with a polygenic effect on milk yield modeled by second order Legendre polynomials for the estimation of variance-covariance parameters and were used for prediction of genomically enhanced breeding values (GEBV). In this model, a matrix combining pedigree and marker-based information was used instead of a traditional numerator relationship matrix. In this matrix the proportions of information coming from pedigree and markers were defined by weighting parameters w and 1-w for pedigree and marker-based information matrices, respectively. Various weights of the two sources of information were considered. The accuracy of GEBV both for genotyped bulls and for cows with phenotypes was highest for weighting parameter w=0 and lowest for w=l. Incorporating genomic information into a conventional genetic evaluation improves reliabilities of breeding value prediction, however, pedigree information is important to maintain the stability of evaluation for non-genotyped animals. Implementation of the single-step approach in a random regression test day model framework is very attractive for genomic prediction in dairy cattle, since it allows to incorporate genomic information directly into a conventional genetic evaluation. However, for accurate predictions it is essential to achieve the right balance between the numerator relationship and markers-based relationship information.

10

Effective monitoring and evaluation of Grain for Green Project in the upper and middle reaches of the Yangtze River

51%

Liu Z., Wang B., Zhao Y., Niu X.

Polish Journal of Environmental Studies

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2019

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tom 28

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nr 2

A comprehensive analysis of normalized difference vegetation index (NDVI), land-use type, and digital elevation model (DEM) data by using the geographic information system (GIS) showed that the index had increased over time in 84 prefectures that were part of the Grain for Green Project. SPOT Vegetation (Satellite Pour l’Observation de la Terre Vegetation, or satellite observation of the earth’s vegetation) data and the NDVI showed that compared to 2000, in 2015 2.05% of the arable land in the study area was no longer cultivated and that 25% of the farmland with slopes steeper than 35° and 2.68% of the moderately sloped farmland (2-35°) had been turned into forests. The arable land had been converted mainly to woodland and grassland. The interpretation of thematic mapper (TM) images showed that forest cover had increased significantly (by nearly 22%); that vegetation cover was less than 10% over 95.27% of the area; and that the area with high vegetation cover had increased significantly. Superposition analysis of TM images and DEM data showed that the intensity of soil erosion had generally decreased, with the areas under mild and pole-strength soil erosion decreasing by more than 10%. However, the Grain for Green Project has failed to check severe soil erosion so far. At present, although 60% of the study area is covered by forests, the extent of change in the degree of vegetation cover varied over time, and the spatial distribution was uneven, being higher in the east than in the west. It is therefore important to continue to strengthen governance through such projects.

11

Revision of the soft-winged flower beetle genus Dicranolaius Champion, 1921 (Coleoptera: Melyridae: Malachiinae) from Australia

51%

Liu Z., Slipinski A., Pang H.

Annales Zoologici

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2017

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tom 67

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nr 3

The Australian Dicranolaius fauna is revised based on 79 described species (30 of them are new). The revision is mainly based on males as they only provide good diagnostic characters for species recognition. The following new species are described: Dicranolaius acacia sp. nov., D. alice sp. nov., D. anic sp. nov., D. archer sp. nov., D. balah sp. nov., D. bogan sp. nov., D. brittoni sp. nov., D. cardaleae sp. nov., D. chinchilla sp. nov., D. confusus sp. nov., D. crypticus sp. nov., D. desertus sp. nov., D. eromanga sp. nov., D. hudsoni sp. nov., D. kildurk sp. nov., D. kimberley sp. nov., D. kinchega sp. nov., D. micrus sp. nov., D. moffatt sp. nov., D. monteithi sp. nov., D. pilbara sp. nov., D. proserpine sp. nov., D. pulleni sp. nov., D. quorn sp. nov., D. reidi sp. nov., D. rockhampton sp. nov., D. spinifex sp. nov., D. thylungra sp. nov., D. uptoni sp. nov., D. zborowskii sp. nov. The following new combinations are proposed: D. ammophilus (Lea, 1917) (Laius), comb, nov., D. distortus (Blackburn, 1888) (Laius), comb, nov., D. egenus (Lea, 1899) (Laius), comb, nov., D. eremita (Blackburn, 1895) (Laius), comb, nov., D. eyrensis (Blackburn, 1892) {Laius), comb, nov., D. guttulatus (Fairmaire, 1877) (Laius), comb, nov., D. melanoderes (Lea, 1917) (Laius), comb, nov., D. minutus (Lea, 1914) (Laius), comb. no\., D.purpureiceps (Lea, 1915) (Laius), comb. nov.,Z>. variegatus (Blackburn, 1889) (Laius), comb, nov., D. verticalis (Macleay, 1826) (Laius), comb, nov., Intybia cavicomis (Lea, 1909) (Laius), comb, nov., Intybia hackeri (Lea) (Laius) comb, nov.; Simoderus megalops (Lea) (Laius) comb. nov. The following synonymies are proposed: D. bellulus (Boisduval, 1835) [= D. cyanocephalus (Lea, 1909); = D. intermedius (Lea, 1909); =D. nidicola (Lea, 1909); =D. orcicornis (Lea, 1909)],D. conicicornis (Blackburn, 1888) [= D. rugiceps (Lea, 1899)], D. guttulatus (Fairmaire, 1877) [= D. longus (Lea, 1929)], D. verticalis (Macleay, 1826) [ = D. tarsalis (Lea, 1909)]. The lectotypes of the following species are designated: Laius acervatus Lea, 1917; L. ammophilus Lea, 1917; L. aulacophoroides Lea, 1917; L. c-pupureus Lea, 1914; L. concavifrons Lea, 1917; L. conicicornis Blackburn, 1888; L. curvicornis Lea, 1929; L. cyanocephalus Lea, 1909; L. distortus Blackburn, 1888; L. egenus Lea, 1899; L. eremita Blackburn, 1851; L. eyrensis Blackburn, 1892; L. fimbriceps Lea, 1929; L. flavifrons Lea, 1917; L. flavonotatus Lea, 1917; L. guttulatus Fairmaire, 1877; L. inconstans Lea, 1921; L. intermedius Lea, 1909; L. intricatus Lea, 1921; L. longus Lea, 1929; L. major Blackburn, 1889; L. mastersii Macleay, 1872; L. melanoderes Lea, 1917; L. minutus Lea, 1914; L. nidicola Lea, 1909; L. orcicornis Lea, 1909; L. orthodoxus Lea, 1909; L. pallidus Lea, 1899; L. plagiaticollis Fairmaire, 1877; L. planiceps Lea, 1899; L. purpureiceps Lea, 1915; L. rugiceps Lea, 1899; L. sinus Lea, 1899; L. tarsalis Lea, 1909; L. tetrasticus Lea, 1922; L. trifoveicornis Lea, 1921; L. variegatus Blackburn, 1889; L. villosus Lea, 1899; Malachius verticalis Macleay, 1826. Neotype oiMalachius bellulus Boisduval, 1835 is also designated.

12

The absorption and enrichment condition of mercury by three plant species

51%

Liu Z., Wang L.-a., Zeng F., Al-Hamadani S. M. Z. F.

Polish Journal of Environmental Studies

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2015

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tom 24

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nr 2

In this paper we studied the absorption condition of three common plant species, Aloevera var.chinensis, Chlorophytum comosum, and Autumn violet. We compared the enrichment ability of three plant species to lay the foundation for exploring the use of plants to repair mercury-contaminated soils. The amount of mercury uptake by three plant species was determined by cold vapor atomic absorption spectrometry. The results demonstrated that all plant species were able to take up Hg to an extent from a nutrient solution containing 800µg/L Hg and mercury-contaminated soils (total mercury content: 0.15-0.20 µg/g soils). However, the Hg translocation to the stems or leaves wasn’t high. The enrichment ability of Chlorophytum comosum was strongest among three plant species.

13

Contribution to the knowledge of the australian Dicranolaius champion (Coleoptera: Melyridae: Malachiinae)

51%

Liu Z., Slipinski A., Pang H.

Annales Zoologici

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2016

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tom 66

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nr 1

Five species of Dicranolaius Champion: D. armstrongianus Wittmer, 1954; D. bellulm (Boisduval, 1835); D. rugulipennis (Fairmaire, 1877); D. spinicornis Wittmer, 1954 and D. villosus (Lea, 1899) are diagnosed, described and illustrated. The lectotypes of Laius rugulipennis Fairmaire, 1877 and Laius nodicornis Blackburn, 1888 have been designated.

14

Ramet recruitment from different bud types along a grassland degradation gradient in Inner Mongolia, China

51%

Qian J., Busso C. A., Wang Z., Liu Z.

Polish Journal of Ecology

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2015

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tom 63

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nr 1

Since the contribution of total belowground bud bank and different bud types to community regeneration has rarely been explored, the vegetative offspring recruited from different belowground bud types was investigated in four plant communities along a grassland degradation gradient in northeastern China (Inner Mongolia). This gradient, between 1000 and 1500 m a.s.l., has been caused by overgrazing. It is a Leymus chinensis steppe which occupies about 3.0×10⁵ ha. Recruitment from tiller buds was dominant (>80%) in determining the total vegetative offspring density along the whole grassland degradation gradient. However, the proportional contribution of tiller-ramets to total ramet recruitment was significantly greater (P <0.05) during earlier than later stages of grassland degradation, while that of rhizome-ramets showed an opposite pattern. While the percentage contribution and density of root-derived ramets to total ramet density increased significantly (P <0.05) during the late stages of grassland degradation, those of bulb-ramets kept relatively constant along the whole grassland degradation gradient. The relative contribution of hemicryptophytes [i.e., Achnatherum sibiricum, Cleistogenes squarrosa, Festuca ovina, Koeoleria cristata, Poa annua, Stipa grandis] to total plant species richness decreased, while that of geophytes [i.e., Agropyron cristatum, Carex korshinskyi. Leymus chinensis, Allium anisopodium, A. bidentatum, A. tenuissimum, Astragalus galactites, Cymbaria dahurica, Iris tenuifolin, Potentilla acaulis, P. bifurca, Pulsatilla turczaninovii, Serratula chinensis, Thalictrum aquilegifolium] increased with the increases of grassland degradation. Our results showed that as grassland degradation increased, changes in the proportion of tiller-, rhizome- and root-derived ramets with respect to total ramet density determined in turn changes in the proportion of hemicryptophytes and geophytes in the study plant communities.

15

Modelling of ship's trajectory planning in collision situations by hybrid genetic algorithm

51%

Ni S., Liu Z., Cai Y., Wang X.

Polish Maritime Research

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2018

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tom 25

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nr 3

Ship collision-avoidance trajectory planning aims at searching for a theoretical safe-critical trajectory in accordance with COLREGs and good seamanship. In this paper, a novel optimal trajectory planning based on hybrid genetic algorithm is presented for ship collision avoidance in the open sea. The proposed formulation is established based on the theory of the Multiple Genetic Algorithm (MPGA) and Nonlinear Programming, which not only overcomes the inherent deficiency of the Genetic Algorithm (GA) for premature convergence, but also guarantees the practicality and consistency of the optimal trajectory. Meanwhile, the encounter type as well as the obligation of collision avoidance is determined according to COLREGs, which is then considered as the restricted condition for the operation of population initialization. Finally, this trajectory planning model is evaluated with a set of test cases simulating various traffic scenarios to demonstrate the feasibility and superiority of the optimal trajectory

16

Advanced treatment of leachate secondary effluent by a combined process of MFPFS coagulation and sulfate radical oxidation

51%

Liu Z., Zhan P., Nie F.

Polish Journal of Environmental Studies

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2016

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tom 25

|

nr 4

Leachate secondary effluent is usually unable to meet the national discharge permit in China and further treatment is a significant challenge because of the residual persistent pollutants. A novel magnetic composite coagulant of MFPFS was prepared from Fe3O4 nanoparticles and polymeric ferric sulfate (PFS). Landfill leachate secondary effluent was treated by MFPFS coagulation combined with sulfate radical oxidation due to Fe2+ activation. Higher COD and color removals were achieved using the MFPFS magnetic coagulant than by adding the coagulant PFS alone. Under the working conditions of 1:3 Fe3O4/PFS mass ratios, 1.2 g/L MFPFS dosage, 50 min sedimentation time, and without pH adjustment, the removals of COD and color reached up to 60% and 80%, respectively. In the oxidation process, Na2S2O8 was activated by Fe2+ to generate sulfate radicals to oxide the residual pollutants in the effluent from MFPFS coagulation. In general, higher temperature, higher dosage, and lower pH were in favor of the oxidation efficiencies. Under the working conditions of 2.4 g/L Na2S2O8 dosage, 0.3 Fe2+/S2O8 2- molar ratio, pH 3.0, and 60ºC temperature, the COD and color removals can reach up to 75% and 95%. After being treated by the combined process, no violation of Chinese effluent standards for landfill leachate was found in respect of each individual parameter, including COD, color, and other parameters like BOD, total nitrogen, and ammonia nitrogen. The combined process was a promising alternative treatment pathway for leachate secondary effluent.

17

Expression pattern of transcription factor SOX2 in reprogrammed oligodendrocyte precursor cells and microglias: Implications for glial neurogenesis

51%

Zhang Y., Qi Y., Liu Z., Xia C.

Acta Neurobiologiae Experimentalis

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2014

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tom 74

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nr 1

Oligodendrocyte Precursor Cells (OPCs) can revert to multipotential Neural Stem-Like Cells (NSLCs) which can self-renew and give rise to neurons, astrocytes and oligodendrocytes when exposed to certain extracellular signals. This is a significant progress to understand developmental neurobiology, in particularly the possibility of converting glia to stem cells for the treatment of neurological disorders. Similarly, recent findings revealed that brain-resident microglias (MGs) can be converted to multipotential state through de-differentiation. In this study, we investigated the role of SRY (sex-determining region)-box 2 (SOX2), a high-mobility group DNA binding domain transcription factor, in the reprogramming of OPCs and MGs and molecular pathways involved in these process. Immunocytochemical analyses demonstrated that expression of SOX2 was upregulated in the reprogrammed MGs and OPCs as well as other neural stem cell markers such as CD15 and nestin. Western blot and double immunostaining analyses further confirmed that activation of bone morphogenetic proteins (BMPs) signaling partnering with SOX2 might be one of the molecular pathways involved in lineage reprogramming of OPCs which is also true in the reversion of MGs. Taken together, these results indicated that lineage reprogramming of OPCs and MGs are both controlled by the same signaling pathway and glia can be reprogrammed in culture by inducing expression of neurogenic transcription factors to transgress their lineage restriction and can stably acquire a neuronal identity. Our results suggested innovative perspectives for cell therapy with glia cells.

18

Effects of varying temperature on leaf phenology and herbivory of dominant tree species in subtropical evergreen broad-leaves forest in Eastern China

51%

Jing J., Li K., Liu Z.

Polish Journal of Ecology

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2016

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tom 64

|

nr 1

The aim of this work was to analyse the response of dominant tree species to the changing climate in a subtropical evergreen broad-leaved forest in China. We investigated the main leaf phenology and herbivory parameters of four typical trees (i.e., Schima superba, Castanopsis fargesii, Castanopsis sclerophylla and Cyclobalanopsis sessilifolia) in spring from 2010 to 2014 in the Tiantong National Forest Research Station in eastern China. The results showed that the accumulated temperature was the principle factor which affected the leaf phenology and herbivory. All four trees got an earlier, shorter and more synchronised leaf expansion in years with higher accumulated temperature, and also they suffered more sever leaf damage in these years. However the trees responded differently to climate warming in leaf phenology and herbivory. The S. superba and Ca. sclerophylla were more sensitive to the varying accumulated temperature than the Ca. fargesii and Cy. sessilifolia both in leaf phenology and herbivory during leaf expansion. We suggest that the observed variations in leaf phenology and leaf traits to the changing accumulated temperature should be taken into consideration for pest management and community stability maintenance in forests adapting to the changing climate.

19

Mutual effects between Pinus armandii and broadleaf litter during mixed decomposition

51%

Zhang X., Wang B., Liu Z.

Acta Societatis Botanicorum Poloniae

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2019

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tom 88

|

nr 2

20

Effects of nitrogen and phosphate enrichment on the activity of nitrate reductase of Ulva prolifera in coastal zone

51%

Zhu M., Liu Z., Shao H., Jin Y.

Acta Physiologiae Plantarum

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2016

|

tom 38

|

nr 07

Ograniczanie wyników

Adaptive sliding mode control for ship autopilot with speed keeping

Pre-filtered backstepping control for underactuated ship path following

Ocena wartosci hodowlanej bydla mlecznego w Niemczech

Enhancing photosynthetic CO2 use efficiency in rice: approaches and challenges