Wyniki wyszukiwania - Biblioteka Nauki

1

Simulation Evaluation Method for Fusion Characteristics of the Optical Camouflage Pattern

100%

Yang X. , Xu W.-D. , Liu J. , Jia Q. , Zhu W.-N.

Fibres & Textiles in Eastern Europe

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2021

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tom Vol. 29, no. 3 (147)

103--110

EN

A comprehensive evaluation system for a camouflage design combining local effect evaluation and global sampling is developed. Different from previous models, this method can sample and evaluate target camouflage in a wide range of combat areas, thereby obtaining a comprehensive evaluation effect. In evaluating local effects, the Gaussian pyramid model is adopted to decompose the image on a multi-scale so that it can conform to the multi-resolution property of human eyes. The Universal Image Quality Index (UIQI) conforming to features of eye movements is then adopted to measure the similarities between multi-scale targeted and background brightness, color and textural features. In terms of the imitation camouflage pattern design algorithm, uniform sampling is used to obtain the evaluation distribution in the background; while for the deformation camouflage pattern, the sampling distribution is improved to make it conform to the movement rule of the target in the background. The evaluation results of the model for different designs were investigated. It is suggested by the experimental results that the model can compare and evaluate the indicators involved in the process of camouflage design, including integration, polychromatic adaptability and algorithm stability. This method can be applied in the evaluation and contrast of camouflage pattern design algorithms, in parameter optimisation of camouflage design and in scheme comparison in engineering practice, and can provide support of evaluation methodology for camouflage design theories.

PL

W pracy opracowano kompleksowy system oceny projektu kamuflażu, łączący ocenę efektu lokalnego i próbkowanie globalne. W odróżnieniu od poprzednich modeli, ta metoda może próbkować i oceniać kamuflaż celu w szerokim zakresie obszarów walki, uzyskując w ten sposób kompleksowy efekt oceny. Oceniając efekty lokalne, przyjęto model piramidy Gaussa w celu dekompozycji obrazu w wielu skalach, tak aby mógł on być zgodny z właściwościami i rozdzielczością ludzkiego oka. Następnie przyjęto uniwersalny wskaźnik jakości obrazu (UIQI) zgodny z cechami ruchów oczu, tak aby zmierzyć podobieństwa między celowaniem w wielu skalach a jasnością tła, kolorem i cechami tekstury. Jeśli chodzi o algorytm projektowania imitacji wzoru kamuflażu, w celu uzyskania rozkładu oceny w tle zastosowano jednolite próbkowanie; podczas gdy w przypadku wzoru kamuflażu deformacji poprawiono rozkład próbkowania, tak aby był zgodny z regułą ruchu celu w tle. Zbadano wyniki oceny modelu dla różnych projektów. Wyniki eksperymentów wykazały, że model może służyć do porównania i oceny wskaźników procesu projektowania kamuflażu, w tym integrację, polichromatyczną adaptowalność i stabilność algorytmu. Metoda przedstawiona w pracy może znaleźć zastosowanie w ocenie algorytmów projektowania wzorów kamuflażu, w optymalizacji parametrów projektowania kamuflażu i przy porównywaniu schematów w praktyce inżynierskiej, a także może stanowić wsparcie dla metodologii oceny teorii projektowania kamuflażu.

2

Infuence of CO2–water–rock interactions on the fracture properties of sandstone from the Triassic Xujiahe Formation, Sichuan Basin

86%

Li H. , Xie L. , Ren L. , He B. , Liu Y. , Liu J.

Acta Geophysica

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2021

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tom Vol. 69, no. 1

135--147

EN

Carbon dioxide (CO2) storage in deep saline aquifers has been lauded as one of the most efective techniques to mitigate greenhouse efects globally. Nevertheless, despite many investigations, clarifying the infuence of CO2–water–rock inter actions on the fracture characteristics of sandstone remains a challenge. In this work, the fracture properties of sandstone collected from the Triassic Xujiahe Formation are systematically studied in tests simulating CO2 sequestration. The results indicate that the water–rock interactions occur in a system of sandstone and CO2 solution. Due to the interactions, the poros ity of sandstone specimens slightly increases from 8.24 to 8.45% when immersed in CO2 solution and from 8.20 to 8.40% in pure water after 28 days. In addition, the parameters of fracture toughness, tensile strength, uniaxial compressive strength and elastic modulus are reduced by 24.12%, 27.16%, 31.78% and 33.21% after immersion in pure water, while they are reduced by 24.05%, 29.72%, 30.75% and 25.79% after immersion in CO2 solution, respectively. These results suggest that the mechanical properties of the Xujiahe sandstone deteriorate after soaking. The results also show that the critical fracture energy of sandstone specimens after immersion in the CO2 solution is 10.4% lower than that in pure water and 24.1% lower than that under natural drying conditions. These research results have great signifcance for understanding the dissolution processes during CO2 sequestration and their infuence on the fracture properties of sandstone, which may be theoretically instructive for CO2 storage in the Xujiahe Formation in the Sichuan Basin.

3

Camouflage Assessments with Digital Pattern Painting Based on the Multi-Scale Pattern-in-Picture Evaluation Model

86%

Jia Q. , Xu W. , Yi Y. , Liu J. , Hu J. , Zhu L. , Yang X.

Fibres & Textiles in Eastern Europe

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2023

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tom Vol. 31, no. 2

39--50

EN

In general, traditional evaluations of target camouflage effects are usually conducted based on observational data and general results of statistical analysis. This widely applied methodology quantifies the detection and identification probabilities of camouflage objects but has considerable shortcomings. This data evaluation process is laborious and time-consuming and very low in reproducibility, which sheds light on the necessity of developing a more efficient method in this study field. The growth of computeraided image processing technology provides technical support for camouflage effect evaluation based on digital image processing. Digital pattern painting, which has been previously applied to combat utility uniforms, is a new methodology full of potential due to its broad geographical adaptability. This study proposes a multi-scale pattern-in-picture method to evaluate camouflage effects at different distances. We also established a computer-aided background image library and camouflage assessments with digital simulation and created an evaluation system that could be effectively applied to combat utility uniforms. More than 40 testers participated in this study, who were asked to score the designed camouflage schemes using the evaluation system proposed. The data from simulation assessments and individual evaluations show that the computer-aided simulation assessments conducted as part of this research can efficiently and objectively evaluate the camouflage effect on military objects.

4

Effect of MoS2 Nanosheet Fillers on Poly(vinyl alcohol) Nanofibre Composites Obtained by the Electrospinning Method

86%

Yuan B. , Liu J. , Qiu L. , Hui Q. , Chang M.-J. , Li Y.-Q.

Fibres & Textiles in Eastern Europe

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2020

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tom Vol. 28, no. 3 (141)

62--67

EN

The graphene-like two dimensional (2D) inorganic materials have been been shown great interest for a variety of applications. In this work, polymer composite nanofibres containing molybdenum disulfide (MoS2) nanosheets were obtained by electrospinning. The MoS2 nanosheets were well dispersed inside the fibres, and the nanofibres maintained the fibre morphology well with the MoS2 nanosheets embedded. The incorporation of MoS2 nanosheets changes polymer nanofibre morphology from round to ribbon-like. Moreover, through thermogravimetric (TG) analysis and dynamic mechanical thermal analysis (DMTA) measurements, it was found that the MoS2 nanosheets as an additive material led to an increase in thermal stability and in the storage modulus. This work comprises an extensive approach to producing a novel 2D inorganic-organic composite structure, which should be applicable for membrane engineering with enhanced thermal and mechanical stability.

PL

Dwuwymiarowe nieorganiczne materiały podobne do grafenu wywołały liczne zainteresowanie w różnych zastosowaniach. W pracy otrzymano metodą elektroprzędzenia kompozytowe nanowłókna polimerowe zawierające disiarczek molibdenu (MoS2). Nanoskładniki MoS2 były dobrze rozproszone we włóknach, a ich morfologia była na zadowalającym poziomie. Włączenie nanoskładników MoS2 zmienia nanowłókna polimerowe z morfologii okrągłej na wstążkową. Co więcej, dzięki analizie termograwimetrycznej (TG) i pomiarom dynamicznej mechanicznej analizy termicznej (DMTA) stwierdzono, że dodatek MoS2 może zapewnić wzrost stabilności termicznej i zwiększyć moduł przechowywania. Praca prezentuje rozszerzone podejście do produkcji nowej dwuwymiarowo nieorganiczno-organicznej struktury kompozytowej, która może mieć zastosowanie w wytwarzaniu membran o podwyższonej stabilności termicznej i mechanicznej.

5

Allelopathy of Native Pinus massoniana Lamb. on Invasive Species : Stronger Effect on Amaranthus retroflexus L. than on Celosia argentea L.

72%

Li C. , Li Y. , Xu Z. , Zhong S. , Liu J. , Xu Z. , Zhu M. , Wei Y. , Wang C. , Du D.

Polish Journal of Ecology

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2023

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tom Vol. 71, nr 4

103--114

EN

Most allelopathic studies have focused only on the allelopathy of invasive plants on the growth performance of native plants, while neglecting the allelopathy of native plants on the growth performance of invasive plants, especially species that can co-invade the same ecosystem. This study aimed to evaluate the allelopathy of the native plant Pinus massoniana Lamb. on the seed germination and seedling growth of two invasive Amaranthaceae species, Celosia argentea L. and Amaranthus retroflexus L. using a germination bioassay. Pinus massoniana showed significant allelopathy on the seed germination and seedling growth of the two invasive Amaranthaceae species. The allelopathy of P. massoniana on the seed germination and seedling growth of the two invasive Amaranthaceae species may be attributed to the effects of the generated stress on their germination activity. Pinus massoniana exhibited stronger allelopathy on the seed germination and seedling growth of A. retroflexus than on that of C. argentea. Thus, the invasiveness of A. retroflexus is expected to be lower than that of C. argentea in contact with P. massoniana. The allelopathy of P. massoniana on the seed germination and seedling growth of the two invasive Amaranthaceae species under the co-cultivated conditions was stronger than that under the monocultural conditions. Accordingly, the aqueous extract of P. massoniana can be considered a potential bioherbicide for the control of the two invasive Amaranthaceae species, particularly when both species co-occuring.

6

Identifcation of gas bearing reservoirs based on the simultaneous inversion of NMR dual TW logging data

72%

Li J. , Zou Y. , Li J. , Pan H. , Hu S. , Su J. , Wang L. , Liu J. , Guo Y.

Acta Geophysica

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2020

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tom Vol. 68, no. 3

667--674

EN

In this paper, we propose a method for obtaining two-dimensional T1–T2 spectrum from simultaneous inversion of the MRIL-Prime tool, dual-TW logging data, in order to improve the accuracy in identifying gas-bearing reservoirs. This paper was accomplished by analyzing the theoretical feasibility of the method, verifying its efectiveness by numerical simulation, and then applying the method to actual logging interpretations to identify gas-bearing reservoirs. The practical application results show that this method can circumvent misidentifcation of reservoirs due to the presence of large pores—a known issue with using a one-dimensional diferential spectrum—and efectively identify gas-bearing reservoirs with low resistivity.