Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Li, Hao" wg kryterium: Autor

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-32 z 32
    Tytuł:
    An implicit weighted degree condition for heavy cycles
    Autorzy:
    Cai, Junqing
    Li, Hao
    Ning, Wantao
    Powiązania:
    https://bibliotekanauki.pl/articles/30148719.pdf
    Data publikacji:
    2014-11-01
    Wydawca:
    Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
    Tematy:
    weighted graph
    hamiltonian cycles
    heavy cycles
    implicit degree
    implicit weighted degree
    Opis:
    For a vertex v in a weighted graph G, idw(v) denotes the implicit weighted degree of v. In this paper, we obtain the following result: Let G be a 2-connected weighted graph which satisfies the following conditions: (a) The implicit weighted degree sum of any three independent vertices is at least t; (b) w(xz) = w(yz) for every vertex z ∈ N(x) ∩ N(y) with xy /∈ E(G); (c) In every triangle T of G, either all edges of T have different weights or all edges of T have the same weight. Then G contains either a hamiltonian cycle or a cycle of weight at least 2t/3. This generalizes the result of Zhang et al. [9].
    Źródło:
    Discussiones Mathematicae Graph Theory; 2014, 34, 4; 801-810
    2083-5892
    Pojawia się w:
    Discussiones Mathematicae Graph Theory
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A note on a new condition implying pancyclism
    Autorzy:
    Flandrin, Evelyne
    Li, Hao
    Marczyk, Antoni
    Woźniak, Mariusz
    Powiązania:
    https://bibliotekanauki.pl/articles/743445.pdf
    Data publikacji:
    2001
    Wydawca:
    Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
    Tematy:
    hamiltonian graphs
    pancyclic graphs
    cycles
    Opis:
    We first show that if a 2-connected graph G of order n is such that for each two vertices u and v such that δ = d(u) and d(v) < n/2 the edge uv belongs to E(G), then G is hamiltonian. Next, by using this result, we prove that a graph G satysfying the above condition is either pancyclic or isomorphic to $K_{n/2,n/2}$.
    Źródło:
    Discussiones Mathematicae Graph Theory; 2001, 21, 1; 137-143
    2083-5892
    Pojawia się w:
    Discussiones Mathematicae Graph Theory
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Pancyclism and small cycles in graphs
    Autorzy:
    Faudree, Ralph
    Favaron, Odile
    Flandrin, Evelynei
    Li, Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/972039.pdf
    Data publikacji:
    1996
    Wydawca:
    Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
    Tematy:
    cycle
    hamiltonian
    pancyclic
    Opis:
    We first show that if a graph G of order n contains a hamiltonian path connecting two nonadjacent vertices u and v such that d(u)+d(v) ≥ n, then G is pancyclic. By using this result, we prove that if G is hamiltonian with order n ≥ 20 and if G has two nonadjacent vertices u and v such that d(u)+d(v) ≥ n+z, where z = 0 when n is odd and z = 1 otherwise, then G contains a cycle of length m for each 3 ≤ m ≤ max (d_C(u,v)+1, [(n+19)/13]), $d_C(u,v)$ being the distance of u and v on a hamiltonian cycle of G.
    Źródło:
    Discussiones Mathematicae Graph Theory; 1996, 16, 1; 27-40
    2083-5892
    Pojawia się w:
    Discussiones Mathematicae Graph Theory
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Dynamic characteristics of underframe semi-active inerter-based suspended device for high-speed train based on LQR control
    Autorzy:
    Wang, Yong
    Li, Hao-Xuan
    Meng, Hao-Dong
    Wang, Yang
    Powiązania:
    https://bibliotekanauki.pl/articles/2173695.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    dynamic characteristics
    high-speed train
    inerter-based suspended device
    LQR control
    Sperling index
    charakterystyka dynamiczna
    pociąg dużych prędkości
    aktywne zawieszenie na bazie inertera
    kontrola LQR
    indeks Sperlinga
    Opis:
    The underframe passive inerter-based suspended device, based on the inerter-spring-damper vibration attenuation structure, could improve the dynamic performance of the train body, but its parameters are fixed and cannot meet the dynamic performance requirements under different operating conditions. Therefore, a semi-active inerter-based suspended device based on the linear quadratic regulator (LQR) control strategy is proposed to further enhance the dynamic performance. The rigid-flexible coupling vertical dynamic model of the train body and an underframe semi-active inerter-based suspended device are established. The structural parameters of the semi-active inerter-based suspended device are adjusted using LQR control strategy. Dynamic response of the system is obtained using the virtual excitation method. The dynamic characteristic of the system is evaluated using the Sperling index and compared with those of the passive and semi-active traditional suspended devices as well as the passive inerter-based suspended devices. The vertical vibration acceleration of the train body and Sperling index using the semi-active inerter-based suspended device is the smallest among the four suspended devices, which denotes the advantages of using the inerter and LQR control strategy. The semi-active inerter-based suspended device could decrease the vertical vibration acceleration of the train body and further suppress its elastic vibration in the lower frequency band, more effectively than the other three suspended devices. Overall, the semi-active inerter-based suspended device could significantly reduce elastic vibration of the train body and improve its dynamical performance.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 4; art. no. e141722
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chvátal-Erdos condition and pancyclism
    Autorzy:
    Flandrin, Evelyne
    Li, Hao
    Marczyk, Antoni
    Schiermeyer, Ingo
    Woźniak, Mariusz
    Powiązania:
    https://bibliotekanauki.pl/articles/743987.pdf
    Data publikacji:
    2006
    Wydawca:
    Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
    Tematy:
    hamiltonian graphs
    pancyclic graphs
    cycles
    connectivity
    stability number
    Opis:
    The well-known Chvátal-Erdős theorem states that if the stability number α of a graph G is not greater than its connectivity then G is hamiltonian. In 1974 Erdős showed that if, additionally, the order of the graph is sufficiently large with respect to α, then G is pancyclic. His proof is based on the properties of cycle-complete graph Ramsey numbers. In this paper we show that a similar result can be easily proved by applying only classical Ramsey numbers.
    Źródło:
    Discussiones Mathematicae Graph Theory; 2006, 26, 2; 335-342
    2083-5892
    Pojawia się w:
    Discussiones Mathematicae Graph Theory
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Note on Neighbor Expanded Sum Distinguishing Index
    Autorzy:
    Flandrin, Evelyne
    Li, Hao
    Marczyk, Antoni
    Saclé, Jean-François
    Woźniak, Mariusz
    Powiązania:
    https://bibliotekanauki.pl/articles/31342189.pdf
    Data publikacji:
    2017-02-01
    Wydawca:
    Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
    Tematy:
    general edge coloring
    total coloring
    neighbor-distinguishing index
    neighbor sum distinguishing coloring
    Opis:
    A total k-coloring of a graph G is a coloring of vertices and edges of G using colors of the set [k] = {1, . . ., k}. These colors can be used to distinguish the vertices of G. There are many possibilities of such a distinction. In this paper, we consider the sum of colors on incident edges and adjacent vertices.
    Źródło:
    Discussiones Mathematicae Graph Theory; 2017, 37, 1; 29-37
    2083-5892
    Pojawia się w:
    Discussiones Mathematicae Graph Theory
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Preparation and Characterization of CL-20 Based Composites by Compressed Air Spray Evaporation
    Autorzy:
    Xu, Wen Zheng
    Peng, Jin Yu
    Wang, Jie
    Li, Hao
    Wang, Jing Yu
    Powiązania:
    https://bibliotekanauki.pl/articles/358401.pdf
    Data publikacji:
    2020
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Tematy:
    CL-20
    CL-20-based composites
    thermal stability
    mechanical sensitivity
    Opis:
    Ultrafine CL-20 particles and three CL-20-based composites were prepared by a compressed air spray evaporation method. All samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and mechanical sensitivity instruments. The results indicated that the thermal stabilities of the CL-20-based composites are better than that of ultrafine CL-20, and that the mechanical sensitivities of ultrafine CL-20 is lower than those of CL-20-based composites. The thermal stability and safety properties of CL-20/Estane 5703 are better than the other samples.
    Źródło:
    Central European Journal of Energetic Materials; 2020, 17, 1; 66-84
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effects of ecological restoration patterns on runoff and sediment in an abandoned coal mine of Southern China
    Autorzy:
    Li, Hao
    Chen, Wenbo
    Zhang, Cheng
    He, Lei
    Liang, Haifen
    Li, Haifeng
    Liu, Dingpu
    Powiązania:
    https://bibliotekanauki.pl/articles/28407391.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    citrus fruit
    soil conservation
    vegetation
    Jiangxi Province
    ecological restoration
    coal mine
    owoce cytrusowe
    ochrona gleby
    wegetacja
    Prowincja Jiangxi
    renowacja ekologiczna
    kopalnia węgla
    Opis:
    Evaluating the ecological economic benefits of different ecological restoration patterns in abandoned mines is important in ecological restoration study. Taking the abandoned coal mine in Luoshi Township of Fengcheng county, Jiangxi province, as a case, 4 different ecological restoration patterns (grapefruit with grass vegetation – Pattern I, pine with grass vegetation – Pattern II, grapefruit – Pattern III, and bare slope – Pattern IV) have been conducted to study the runoff and sediment yield under natural rainfall conditions. The results showed that the ecological restoration patterns and rainfall intensity can significantly affect runoff and sediment yield which increased as rainfall intensity increased: Pattern IV > Pattern III > Pattern II > Pattern I. For the optimal ecological restoration with Pattern I, the average runoff and sediment reduction was 59.01 and 77.1%, respectively, in all rainfall intensities. Multivariate analysis of variance (MANOVA) showed that runoff and sediment were significantly affected by ecological restoration pattern and rainfall intensity (P < 0.05). Correlation analysis of runoff and sediment yields indicated that the reduction effect on sediment yield increased with the decrease of runoff, and the relationships between runoff and sediment at different ecological restoration patterns could be fitted with a linear function. Moreover, the vegetation configuration that combines fruit farming with grass can be not only beneficial to control soil and water conservation but produce considerable economic and ecological benefits.
    Źródło:
    Environment Protection Engineering; 2023, 49, 4; 29--44
    0324-8828
    Pojawia się w:
    Environment Protection Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comprehensive Analysis of Metal Deformation Law Based on Numerical Simulation of Cold Rolling Process
    Autorzy:
    Yan, Zhu-Wen
    Wang, Bao-Sheng
    Bu, He-Nan
    Li, Hao
    Hong, Lei
    Zhang, Dian-Hua
    Powiązania:
    https://bibliotekanauki.pl/articles/2106570.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    3D elastic-plastic FEM
    work roll deflection
    lateral thickness
    flatness regulation effect
    rolling pressure
    Opis:
    Through taking the cold rolling process as the research object, the three-dimensional finite element model of the strip rolling process is established by using ANSYS/LS-DYNA software. The actual rolling product data has strong consistency with the finite element simulation results. The rolling process is dynamically simulated, and the distribution curves of important rolling parameters such as equivalent stress, control efficiency coefficient, transverse rolling pressure, lateral thickness and work roll deflection is obtained. Based on summarizing the influence of rolling parameters on rolling deformation, the research results of this paper can play an important role in the actual rolling process control. The research results have certain guiding significance for the development and optimization of the rolling control system.
    Źródło:
    Archives of Metallurgy and Materials; 2022, 67, 2; 623--635
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fault mode analysis and reliability optimization design of a mechanical interface based on cylindrical cam mechanisms
    Autorzy:
    Li, Jian-Hao
    Liu, Zhi-Jie
    Wang, Da-Peng
    Tian, Yun
    Zhao, Yu-Chong
    Powiązania:
    https://bibliotekanauki.pl/articles/1841922.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
    Tematy:
    mechanical interface
    fault mode analysis
    Monte Carlo simulation
    reliability design
    cylindrical cam mechanism
    Opis:
    The mechanical interface has the characteristics of low shock and vibration, and is emphasized in the aerospace and ocean engineering fields. In this paper, a mechanical interface based on coupled cylindrical cam mechanisms is designed. It can achieve the expected functions, but there exist faults in some times. The fault modes and causes of the interface are firstly analyzed. Then a design approach based on Monte Carlo simulation is presented for analyzing and optimizing its reliability. According to the fault modes, the performance functions of the interface are established for obtaining the optimal scheme. A case is given to illustrate the proposed method. The simulation results and the prototype experiments prove that the optimization scheme effectively improves the reliability of the interface, and has better performance than the original one.
    Źródło:
    Eksploatacja i Niezawodność; 2020, 22, 4; 715-723
    1507-2711
    Pojawia się w:
    Eksploatacja i Niezawodność
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optical coherence tomography image for automatic classification of diabetic macular edema
    Autorzy:
    Wang, Ping
    Li, Jia-Li
    Ding, Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/1835815.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    diabetic macular edema
    optical coherence tomography
    transfer learning
    fine-tuning
    Opis:
    Diabetic macular edema (DME) is the dominant reason of diabetic visual loss, so early detection and treatment of DME is of great significance for the treatment of diabetes. Based on transfer learning, an automatic classification method is proposed to distinguish DME images from normal images in optical coherence tomography (OCT) retinal fundus images. Features of the DME are automatically identified and extracted by the pre-trained convolutional neural network (CNN), which only involves fine-tuning the VGGNet-16 network without any user intervention. An accuracy of 97.9% and a sensitivity of 98.0% are acquired with the OCT images in the Duke data set from experimental results. The proposed method, a core part of an automated diagnosis system of the DME, revealed the ability of fine-tuning models to train non-medical images, allowing them can be classified with limited training data. Moreover, it can be developed to assist early diagnosis of the disease, effectively delaying (or avoiding) the progression of the disease, consequently.
    Źródło:
    Optica Applicata; 2020, 50, 4; 567-577
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simultaneous integrated optimization for underground mine planning: application and risk analysis of geological uncertainty in a gold deposit
    Zintegrowany model optymalizacji planowania robót górniczych w podziemnych kopalniach: analiza ryzyka i niepewności geologicznej w złożach złota
    Autorzy:
    Hou, Jie
    Li, Guoqing
    Hu, Nailian
    Wang, Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/216053.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
    Tematy:
    underground mine
    mine planning
    integrated optimization
    geological uncertainty
    integer programming
    kopalnia podziemna
    planowanie robót górniczych
    zintegrowana optymalizacja
    niepewność geologiczna
    programowanie całkowitoliczbowe
    Opis:
    The main optimized objects in underground mines include: stope layout, access layout and production scheduling. It is common to optimize each component sequentially, where optimal results from one phase are regarded as the input data for the next phase. Numerous methods have been developed and implemented to achieve the optimal solution for each component. In fact, the interaction between different phases is ignored in the tradition optimization models which only get the suboptimal solution compared to the integrated optimization model. This paper proposes a simultaneous integrated optimization model to optimize the three components at the same time. The model not only optimizes the mining layout to maximize the Net Present Value (NPV), but also considers the extension sequence of stope extraction and access excavation. The production capacity and ore quality requirement are also taken into account to keep the mining process stable in all mine life. The model is validated to a gold deposit in China. A two-dimensional block model is built to do the resource estimation due to the clear boundary of the hanging wall and footwall. The thickness and accumulation of each block is estimated by Ordinary Kriging (OK). In addition, the conditional simulation method is utilized to generate a series of orebodies with equal possibility. The optimal solution of optimization model is carried out on each simulated orebody to evaluate the influence of geological uncertainty on the optimal mining design and production scheduling. The risk of grade uncertainty is quantified by the possibility of obtaining the expected NPV. The results indicate that the optimization model has the ability to produce an optimal solution that has a good performance under the uncertainty of grade variability.
    Główne optymalizowane obiekty w kopalniach podziemnych to parametry struktury przodka wybierkowego, optymalnego udostępnienia oraz planowanie robót górniczych. Powszechne jest optymalizowanie każdego komponentu po kolei, przy czym optymalne wyniki jednej fazy są uważane za dane wejściowe dla następnej. Opracowano i wdrożono wiele metod w celu uzyskania optymalnego rozwiązania dla każdego komponentu. W rzeczywistości interakcja między różnymi fazami jest ignorowana w tradycyjnych modelach optymalizacji, które prowadzą do nieoptymalnych rozwiązań w porównaniu ze zintegrowanym modelem optymalizacji. Niniejszy artykuł przedstawia zintegrowany model optymalizacji optymalizujący trzy komponenty w tym samym czasie. Model nie tylko optymalizuje układ wydobywczy, aby zmaksymalizować wartość bieżącą netto (NPV), ale także uwzględnia parametry przodka wybierkowego oraz wkopu udostępniającego złoże. Aby utrzymać proces wydobycia na stałym poziomie przez cały czas trwania eksploatacji, pod uwagę brane są również zdolności produkcyjne oraz wymagania dotyczące jakości rudy. Omawiany model jest opracowany na potrzeby złoża złota w Chinach. Powstały dwuwymiarowy model blokowy do oszacowania zasobów ze względu na wyraźną granicę między skrzydłem wiszącym a spągowym. Grubość i akumulacja każdego bloku jest szacowana za pomocą krigingu zwyczajnego (OK). Dodatkowo wykorzystywana jest warunkowa symulacja w celu generowania szeregu złóż rudy. Optymalny model optymalizacji jest przeprowadzany na każdym symulowanym złożu w celu oceny wpływu niepewności geologicznej na optymalne planowanie robót górniczych i produkcji. Ryzyko odnośnie do niepewności jakości złoża jest kwantyfikowane przez możliwość uzyskania oczekiwanej wartości bieżącej netto (NPV). Wyniki wskazują, że model optymalizacji ma zdolność do tworzenia optymalnego rozwiązania w warunkach niepewności.
    Źródło:
    Gospodarka Surowcami Mineralnymi; 2019, 35, 2; 153-174
    0860-0953
    Pojawia się w:
    Gospodarka Surowcami Mineralnymi
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A system reliability-based design optimization for the scraper chain of scraper conveyors with dependent failure modes
    Oparta na niezawodności systemu optymalizacja konstrukcji łańcucha przenośnikowego zgrzebłowego o zależnych przyczynach uszkodzeń
    Autorzy:
    Shuai, Li
    Zhencai, Zhu
    Hao, Lu
    Gang, Shen
    Powiązania:
    https://bibliotekanauki.pl/articles/301804.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
    Tematy:
    probabilistic analysis
    system reliability
    Copula
    scraper chain
    optimization
    analiza probabilistyczna
    niezawodność systemu
    funkcja kopuły
    łańcuch przenośnikowy zgrzebłowy
    optymalizacja
    Opis:
    With the incomplete probability information, the joint probability distribution modelling and system reliability-based optimization design of structural systems with failure interactions are challenging problems in the domain of reliability. This article is designed to propose a system reliability-based optimization design method for optimizing the scraper chain with multiple failure modes. Firstly, the common failure modes of the scraper chain are analysed. For each failure mode, a reliability model for the failure of scraper chains is obtained. Secondly, aiming at the joint failure probability modelling problem, a method for estimating the failure probability of the scraper chain based on system reliability is proposed. The reliability of scraper chains is calculated by the stochastic perturbation technique and the four-moment method. And then, the optimization design problem is discussed based on system reliability. And the optimal model is established. Finally, the effectiveness of the method is verified by the illustrative example of scraper chains. The proposed joint failure probability estimation method and design optimization are shown in the example. The results obtained can provide a reference for the optimal design of the scraper chain.
    Ze względu na niekompletność danych dotyczących prawdopodobieństwa, modelowanie wspólnego rozkładu prawdopodobieństwa oraz oparte na niezawodności systemu projektowanie optymalizacyjne systemów konstrukcyjnych, w których zachodzą zależności między uszkodzeniami stanowią trudne problemy niezawodnościowe. W artykule zaproponowano metodę optymalizacji konstrukcji łańcucha zgrzebłowego, w której wykorzystuje się obliczenia niezawodności systemu. Ponieważ dla łańcucha tego typu istnieje wiele potencjalnych przyczyn uszkodzeń, w pierwszej kolejności analizowano powszechnie występujące przyczyny uszkodzeń. Dla każdego rodzaju uszkodzenia łańcucha otrzymano model niezawodnościowy. Następnie, mając na uwadze problem modelowania wspólnego rozkładu prawdopodobieństwa uszkodzeń, zaproponowano metodę szacowania prawdopodobieństwa uszkodzenia łańcucha na podstawie niezawodności systemu. Niezawodność łańcuchów zgrzebłowych obliczano za pomocą techniki zaburzeń stochastycznych oraz metody momentu czwartego rzędu. Na podstawie otrzymanej niezawodności systemu, omówiono problem optymalizacji konstrukcji łańcucha oraz wyznaczono model optymalny. Skuteczność proponowanych metod estymacji wspólnego prawdopodobieństwa uszkodzenia i optymalizacji konstrukcji weryfikowano na podstawie przykładu łańcucha zgrzebłowego. Uzyskane wyniki mogą stanowić punkt odniesienia dla optymalnego projektowania łańcuchów zgrzebłowych.
    Źródło:
    Eksploatacja i Niezawodność; 2019, 21, 3; 392-402
    1507-2711
    Pojawia się w:
    Eksploatacja i Niezawodność
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Experimental study of fuel combustion and emission characteristics of marine diesel engines using advanced fuels
    Autorzy:
    Changxiong, Li
    Hu, Yihuai
    Yang, Zy
    Guo, Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/34615637.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
    Tematy:
    marine diesel engine
    PODE
    combustion characteristics
    emission performance
    Opis:
    In order to explore the potential application of oxygenated fuels, polyoxymethylene dimethyl ethers (PODE), as an alternative fuel for marine diesel engines, the fuel combustion performance and gas emission characteristics of pure diesel oil, diesel-blended PODE, and pure PODE were tested on a marine diesel engine under different running conditions. The experimental results indicate that oxygen consumption can be reduced by diesel-blended PODE and pure PODE. The in-cylinder pressure and exothermic curve were consistent with the trend of diesel oil. Also, the ignition delay of diesel-blended PODE and pure PODE decreased, and the diffusion rate was accelerated, which helped to improve the combustion performance of diesel engines. Diesel blended PODE and pure PODE reduced the particulate matter (PM) emissions by up to 56.9% and 86.8%, respectively, and CO emissions by up to 51.1% and 56.3%, respectively. NOx emissions were gradually decreased with engine load. CO2 emissions were slightly increased, and the effective fuel consumption was increased up to 48% and 132%, respectively. It was shown that PODE could provide comparable power in a marine diesel engine and improve the fuel combustion and gas emission of the engine as a clean alternative fuel for marine diesel engines.
    Źródło:
    Polish Maritime Research; 2023, 3; 48-58
    1233-2585
    Pojawia się w:
    Polish Maritime Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal stability and mechanical properties of hybrid materials based on nitrocellulose grafted by aminopropylisobutyl polyhedral oligomeric silsesquioxane
    Stabilność termiczna i właściwości mechaniczne materiałów hybrydowych na bazie nitrocelulozy szczepionej oligomerycznym wielofunkcyjnym aminopropyloizobutylosilseskwioksanem
    Autorzy:
    Yang, X.
    Wang, Y.
    Li, Y.
    Li, Z.
    Song, T.
    Liu, X.
    Hao, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/945783.pdf
    Data publikacji:
    2017
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
    Tematy:
    nitrocellulose
    hybrid material
    aminopropylisobutyl polyhedral oligomeric silsesquioxane
    thermal stability
    mechanical properties
    nitroceluloza
    materiał hybrydowy
    oligomeryczny wielofunkcyjny aminopropyloizobutylosilseskwioksan
    stabilność termiczna
    właściwości mechaniczne
    Opis:
    The need for improvement in nitrocellulose (NC) storage safety and convenience of application requires an increase in NC thermal stability and enhancement of its mechanical properties. To this aim, hybrid materials were synthesized by grafting NC with aminopropylisobutyl polyhedral oligomeric silsesquioxane (amino-POSS) using isophorone diisocyanate (IPDI) as a crosslinking agent. The structure and elemental composition of the resulting products were confirmed by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H NMR and 29Si NMR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). It was found, based on the silicon mapping using energy dispersive X-ray spectroscopy (EDS), that amino-POSS was well dispersed in NC matrix. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) studies showed that hybrid amino-POSS-NC materials have higher thermal decomposition activation energy (Ea) compared to NC control sample. According to TGA results, the temperatures of 5 % weight loss (T5 %) and 50 % weight loss (T50 %) as well as the residual masses at 240 °C (CR240 °C), were increased as a result of NC modification with amino-POSS. As can be seen from the digital and scanning electron microscopy (SEM) images, the char layers of amino-POSS-NC hybrid materials after burning in air became more compact with increasing amino-POSS content. XPS studies have shown an increased content of the graphitized carbon in the char residues of the modified samples. The results of DSC, TGA, SEM and XPS studies have directly proved the enhancement of the thermal stability of amino-POSS-NC hybrid materials. In addition, tensile strengths and Young's moduli of amino-POSS-NC hybrid materials were increased gradually with the amino-POSS content in the uniaxial tensile tests. All these results show that the proposed modification of nitrocellulose improves the safety of manufacture and use of this material.
    Poprawa bezpieczeństwa przechowywania nitrocelulozy (NC) wymaga zwiększenia jej stabilności termicznej, a wygoda używania poprawy właściwości mechanicznych. W tym celu zsyntetyzowano materiały hybrydowe, w których NC szczepiono oligomerycznym wielofunkcyjnym aminopropyloizobutylosilseskwioksanem (amino-POSS) stosując jako środek sieciujący izoforonodiizocyjanian (IPDI). Strukturę i skład otrzymanych materiałów potwierdzono za pomocą spektroskopii w podczerwieni z transformatą Fouriera (FT-IR), jądrowego rezonansu magnetycznego (1H NMR i 29SiNMR), dyfraktometrii rentgenowskiej (XRD) oraz spektroskopii fotoelektronów rentgenowskich (XPS). Na podstawie wyników badań mapowania Si, otrzymanych metodą spektroskopii dyspersji energii promieniowania rentgenowskiego (EDS), stwierdzono, że amino-POSS został dobrze zdyspergowany w matrycy NC. Badania stabilności termicznej przeprowadzone za pomocą różnicowej kalorymetrii skaningowej (DSC) wykazały, że materiały hybrydowe typu amino-POSS-NC charakteryzują się większymi wartościami energii aktywacji rozkładu termicznego (Ea) niż próbka kontrolna NC. Zgodnie z wynikami analizy termograwimetrycznej (TGA) wartości temperatury ubytku 5 % (T5 %) i 50% (T50 %) masy próbki oraz pozostałości masy w temperaturze 240 °C (CR240 °C) zwiększały się na skutek modyfikacji NC za pomocą amino-POSS. Według fotografii cyfrowych i fotografii wykonanych metodą skaningowej mikroskopii elektronowej (SEM) warstwy węglowe powstałe po spaleniu materiałów hybrydowych w powietrzu wraz ze zwiększeniem zawartości amino-POSS stawały się coraz bardziej zwarte, a wyniki badań XPS wykazały, że tworzyło się coraz więcej węgla w postaci grafitu. Wszystkie wyniki DSC, TGA, SEM i XPS dowodzą poprawy stabilności termicznej materiałów hybrydowych amino-POSS-NC. Stwierdzono także, że wytrzymałość na rozciąganie i moduł Young'a podczas prób jednoosiowego rozciągania materiałów hybrydowych rosną ze zwiększaniem się zawartości amino-POSS. Wyniki wszystkich przeprowadzonych badań dowodzą, że zaproponowana modyfikacja NC poprawia bezpieczeństwo wytwarzania i użytkowania tych materiałów w porównaniu z niemodyfikowanym NC.
    Źródło:
    Polimery; 2017, 62, 7-8; 576-587
    0032-2725
    Pojawia się w:
    Polimery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Genotypic variation of Cunninghamia lanceolata revealed by phenotypic traits and SRAP markers
    Autorzy:
    Zheng, H.
    Duan, H.
    Hu, D.
    Li, Y.
    Hao, Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/41212.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Instytut Dendrologii PAN
    Opis:
    The success of a tree breeding program largely depended on the available genetic variability of the germplasms. Our present study aimed to assess the phenotypic variation and DNA variability using sequence-related amplified polymorphism (SRAP) markers among 50 Cunninghamia lanceolata (Chinese fir) genotypes. Extensive phenotypic variations (p < 0.05 or 0.01) were found for all the growth and wood property traits (height, diameter at breast height, stem volume, and wood basic density, hygroscopicity, heart-wood ratio, tracheid length, tracheid diameter and tracheid length-diameter ratio) with coefficients of variation spanning from 6.8 to 31.3%. At the DNA level, thirty-five SRAP primer combinations produced 498 bands with 89.4% polymorphism across genotypes; moreover, the Nei’s gene diversity was detected to be ranged between 0.204 and 0.373 (mean = 0.279), while the Shannon’s Information Index stretched from 0.324 to 0.555 with an average value of 0.427. Significance (p < 0.01) of the variability of SRAP polymorphism among genotypes was further demonstrated by AMOVA. These results indicated a relatively high level of genetic diversity in genotypes. The SRAP’ dendrogram additionally revealed that these genotypes could be split into 7 clusters with higher discriminating capacity over that of phenotype. Notably, a total of 99 statistically significant (p < 0.05) marker-trait associations related to the growth and wood property traits were identified. These marker-trait associations corresponded to 77 different SRAP markers with R2 (percentage of the phenotypic variation explained by marker) ranging from 8.3 to 26.4%.
    Źródło:
    Dendrobiology; 2015, 74
    1641-1307
    Pojawia się w:
    Dendrobiology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Basic theory and optimization of gold containing antimony concentrate leaching by alkaline sulfide
    Autorzy:
    Wu, Hao
    Feng, Yali
    Li, Haoran
    Liao, Shengde
    Wang, Hongjun
    Powiązania:
    https://bibliotekanauki.pl/articles/109524.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    antimony concentrate
    leaching process
    alkaline leaching
    kinetics
    Opis:
    As sodium sulfide is easily oxidized to polysulfide and thiosulfate which have a gold leaching effect, gold would dissolve in leaching solution when extracting stibium from gold containing antimony concentrate by alkaline sulfide. Through leaching test and kinetics analysis, the decomposition regularity of sodium sulfide and leaching rate were studied under different leaching conditions. The results indicated that the gold content in antimony concentrate was 28.41g/Mg, and the content of antimony and sulfur was 36.01% and 14.04%, respectively. The main metallic minerals were native gold, arsenopyrite, stibnite, and the gangue minerals were mainly quartz. Anodic polarization curve shows reduced iron powder can increase the peak potential of the oxidation of the leaching solution and it can effectively prevent the decomposition of sodium sulfide and the dissolution of gold. Optimized stibium-extraction efficiency was achieved under the following conditions: a concentration of sodium sulfide and sodium hydroxide at 110g/dm³ and 20g/dm³, respectively; a ratio of iron powder to concentrate of 1:30; a ratio of liquid to solid of 5:1; agitation speed of 600rad/min; reaction temperature of 353.15K; and a reaction time of 3 h. Under the optimized conditions, high antimony recovery (97.35%) and low gold dissolution (1.32%) were achieved.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2019, 55, 1; 248-257
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Self-extinguishing low-nitrogen nitrocellulose based on synergistic effect of dimethyl methylphosphonate and long-chain chlorinated paraffin
    Samogasnąca nitroceluloza o małej zawartości azotu z dodatkiem synergicznie działających dimetylofosfonianu metylu i długołańcuchowej chlorowanej parafiny
    Autorzy:
    Yang, X.
    Wang, J.
    Song, T.
    Li, Z.
    Hao, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/947543.pdf
    Data publikacji:
    2018
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
    Tematy:
    nitrocellulose
    dimethyl methylphosphonate
    chlorinated paraffin
    multi-flame retardancy mechanism
    nitroceluloza
    dimetylofosfonian metylu
    chlorowana parafina
    wielofazowy mechanizm uniepalniania
    Opis:
    A series of flame retardant low-nitrogen nitrocelluloses (FR/NCs) containing different weight ratios of dimethyl methylphosphonate (DMMP) and long-chain chlorinated paraffin (CP) were directly prepared by blending method, and the burning behaviors, thermal and mechanical properties, pyrolysis process and char residues were investigated.The results showed that (DMMP/CP = 8/2)/NC at a total flame retardant loading of 17 wt % displayed the self-extinguishing behavior following a multi-flame retardancy mechanism with synergistic effect that includes gas-phase effects, endothermic effectsand slightly condensed-phase effects of flame retardancy. In addition, the tensile properties of the (DMMP/CP = 8/2)/NC revealed a synergistic plasticization effect, which could enhance the flexibility of NC. This new system provided a reference for improving a safety storage and widely application of NC in the future.
    Metodą bezpośredniego mieszania składników otrzymano serię trudnopalnej nitrocelulozy o małym udziale azotu (NC) zawierającej dimetylofosfonian metylu (DMMP) zmieszany w różnych stosunkach masowych z długołańcuchową chlorowaną parafiną (CP). Oceniano właściwości palne, termiczne i mechaniczne wytworzonych mieszanin, badano również proces ich pirolizy, a także zwęgloną pozostałość po spaleniu. Stwierdzono, że mieszanina (DMMP/CP = 8/2)/NC z udziałem 17 % mas. uniepalniaczy charakteryzowała się zdolnością do samogaśnięcia w wyniku synergicznego wielofazowego mechanizmu uniepalniającego, obejmującego fazy gazową i częściowo skondensowaną, a także efekt endotermiczny. Dodatkowo właściwości wytrzymałościowe przy rozciąganiu wspomnianej mieszaniny wskazywały na synergiczne działanie plastyfikujące zastosowanych związków uniepalniających. Opracowana mieszanina pozwala na zwiększenie bezpieczeństwa przechowywania i użytkowania nitrocelulozy.
    Źródło:
    Polimery; 2018, 63, 6; 424-435
    0032-2725
    Pojawia się w:
    Polimery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Continuous Growth of Bulk Si by Temperature Gradient Zone Melting Method
    Autorzy:
    Li, Jiayan
    Wang, Liang
    Hao, Jianjie
    Ni, Ping
    Tan, Yi
    Powiązania:
    https://bibliotekanauki.pl/articles/356541.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    bulk Si
    TGZM
    Si-Al alloy
    growth rate
    impurities
    Opis:
    Temperature gradient zone melting (TGZM) method was used to obtain bulk Si continuously for the efficient separation and purification of primary Si from the Si-Al alloy in this work. The effects of alloy thickness, temperature gradient and holding time in TGZM purification technology were investigated. Finally, the continuous growth of bulk Si without eutectic inclusions was obtained. The results showed that the growth rate of bulk Si was independent of the liquid zone thickness. When the temperature gradient was changed from 2.48 K/mm to 3.97 K/mm, the growth rate of bulk Si was enhanced from 7.9×10-5 mm/s to 2.47×10-4 mm/s, which was increased by about 3 times. The bulk Si could grow continuously and the growth rate was decreased with the increase of holding time from 1 h to 5 h. Meanwhile, low refining temperature was beneficial to the removal of impurities. With a precipitation temperature of 1460 K and a temperature gradient of 2.48 K/mm, the removal rates of Fe, P and B were 99.8%, 94.0% and 63.6%, respectively.
    Źródło:
    Archives of Metallurgy and Materials; 2019, 64, 1; 271-278
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Parameter identification approach using improved teaching and learning based optimization for hub motor considering temperature rise
    Autorzy:
    Li, Yong
    Wang, Yuan
    Zhang, Taohua
    Hu, Han
    Wu, Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/2203368.pdf
    Data publikacji:
    2023
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    parameters identification
    teaching–learning-based optimization
    hub motor
    temperature rise
    Opis:
    Temperature rise of the hub motor in distributed drive electric vehicles (DDEVs) under long-time and overload operating conditions brings parameter drift and degrades the performance of the motor. A novel online parameter identification method based on improved teaching-learning-based optimization (ITLBO) is proposed to estimate the stator resistance, -axis inductance, -axis inductance, and flux linkage of the hub motor with respect to temperature rise. The effect of temperature rise on the stator resistance, -axis inductance, -axis inductance, and magnetic flux linkage is analysed. The hub motor parameters are identified offline. The proposed ITLBO algorithm is introduced to estimate the parameters online. The Gaussian perturbation function is employed to optimize the TLBO algorithm and improve the identification speed and accuracy. The mechanisms of group learning and low-ranking elimination are established. After that, the proposed ITLBO algorithm for parameter identification is employed to identify the hub motor parameters online on the test bench. Compared with other parameter identification algorithms, both simulation and experimental results show the proposed ITLBO algorithm has rapid convergence and a higher convergence precision, by which the robustness of the algorithm is effectively verified.
    Źródło:
    Metrology and Measurement Systems; 2023, 30, 1; 99--115
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Gold recovery from refractory gold concentrates by pressure oxidation pre-treatment and thiosulfate leaching
    Autorzy:
    Yu, Li
    Li, Shimei
    Liu, Quanjun
    Deng, Jiushuai
    Luo, Bin
    Liang, Yuanqin
    Zhao, Liuchuang
    Lai, Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/110871.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    gold
    pressure oxidation
    thiosulfate
    leaching
    RSM
    Opis:
    Naturally, refractory gold is enclosed by sulfide minerals such as pyrite and arsenopyrite and a higher content of organic carbon, which results in difficulty in the recovery of gold. In this study, the flotation gold concentrate before and after pressure oxidation (POX) was analyzed. The analysis of the Eh-pH diagram revealed that pyrite/arsenopyrite would be dissolved in higher oxidation potential. Results of SEM-EDS showed that the surface of minerals became very rough and structure of some particles was destroyed after POX. The XRD measurement showed that pyrite was oxidized to jarosite, and gangue minerals such as quartz and organic carbon were hardly changed. The process of thiosulfate leaching of gold was designed and optimized according to Miscellaneous implemented by Response Surface Methodology (RSM). Based on the results of ANOVA, leaching model was significant. In leaching, [S2O32-] played an important role and the interactions between [S2O32-] and [Cu2+] were significant. The effect of [HA] was relatively weak. Optimum process parameters of the initial reagent concentration were 505.00 mM for [S2O32-], 34.77 mM for [Cu2+], and 0.50 mM for [HA]. Under these conditions, the Au extraction value was about 86.21%, which was significantly higher than that obtained with leaching directly.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2019, 55, 2; 537-551
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparative evaluation of wear behavior of tribo-pairs in reciprocating pumps with multiple materials under different conditions
    Autorzy:
    Li, Ran
    Wei, Wenshu
    Liu, Hao
    Wang, Dalong
    Ye, Jian
    Li, Shoubin
    Wang, Wei
    Wu, Huigang
    Powiązania:
    https://bibliotekanauki.pl/articles/2200870.pdf
    Data publikacji:
    2023
    Wydawca:
    Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
    Tematy:
    reciprocating pump
    tribo-pair
    cast iron pin
    wear behavior
    wear resistance
    Opis:
    In the study of wear behavior of tribo-pairs in reciprocating pumps, the tribo-pairs can be considered as contact pairs consisting of a disc and pin. In this paper, pin-on-disc wear tests were carried out by using two types of cast iron pin specimens with different materials. Additionally, the effects of the lubrication condition, test load, diamond-like carbon (DLC) coating and plateau honing cross-hatch pattern on wear behavior of the tribo-pairs were investigated. Experimental results based on surface topography analysis and scanning elec- tron micrograph (SEM) analysis show that the lubricant and DLC coating have a positive effect on wear resistance of test specimens. Disc specimens of three material types (i.e. ISO 185/JL/250, tin-bronze, zirconia) are able to show good anti-wear behavior. The tribo-pairs composed of spheroidal graphite cast irons as well as implementation of the plateau honing cross hatch on disc specimens have no significant effect on the wear resistance. The Archard model was used to estimate abrasive wear under dry conditions, which was over-predicted compared to the experimental results.
    Źródło:
    Journal of Theoretical and Applied Mechanics; 2023, 61, 1; 77--87
    1429-2955
    Pojawia się w:
    Journal of Theoretical and Applied Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Solution Growth of Well-Aligned ZnO Nanorods on Sapphire Substrate
    Autorzy:
    Jia, G.
    Hao, B.
    Lu, X.
    Wang, X.
    Li, Y.
    Yao, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1399510.pdf
    Data publikacji:
    2013-07
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    68.37.Yz
    78.40.Fy
    68.55.J-
    Opis:
    Vertically well-aligned ZnO nanorods arrays were synthesized on sapphire substrates by chemical bath deposition. Those sapphire substrates were seeded to control the density and orientation of ZnO nanorods using sol-gel method. Well-aligned and uniformly distributed ZnO nanorods in a large scale were obtained with strongly (002) preferential orientation. The structural properties were characterized by X-ray diffraction spectrometer and morphological characteristics were analyzed by scanning electron microscopy, respectively. The ZnO nanorods are obvious hexangular wurtzite structure and preferentially oriented along the c-axis (002) and growth vertically to the substrates. The optical properties were further thoroughly studied. What is more, the influences of the strain between substrate and ZnO nanorods due to thickness of the ZnO seed-layer on the characteristics and optical properties of ZnO were also analyzed.
    Źródło:
    Acta Physica Polonica A; 2013, 124, 1; 74-77
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Strain measurement based on fixed wavelength transmission of tapered long-period fiber grating
    Autorzy:
    Tang, Yong
    Zhang, Hao
    Zhang, Li
    Yu, Xin Feng
    Bai, Yun Feng
    Powiązania:
    https://bibliotekanauki.pl/articles/2172862.pdf
    Data publikacji:
    2022
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    tapered fiber
    long-period fiber
    fiber grating
    strain sensor
    fixed dual-wavelength ratio
    Opis:
    This paper studies the relationship between transmission intensity and strain based on tapered long-period fiber grating at a fixed wavelength. In experiments, tapered long-period fiber grating was prepared by the electric melting method. Experimental results show that two resonance peaks appeared at 1482 and 1537 nm, respectively. Here is the elaboration of the relationship between the resonant wavelength and the strain, its wavelength-strain sensitivity is 20 pm/με, and the linearity was negative. Then our next study was about the relationship between transmission intensity and strain at a fixed wavelength. The results show that the transmission intensity at a fixed wavelength is related to the exponent with strain. The coupled-mode theory is applied to simulate the relationship between fixed wavelength and strain. The simulation results matched the experimental results. Two fixed wavelength transmission intensity ratio was used, and the ratio showed a linear relationship with the strain, and the slope is –0.018 dB/με. Therefore, within the 0.01% resolution of our detector, we could resolve a 0.16 με strain change. We can select the appropriate light source and detector to achieve higher measurement accuracy. Thus, there is a great potential in fiber grating strain sensors.
    Źródło:
    Optica Applicata; 2022, 52, 4; 511--519
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Activation mechanism of tantalum niobium flotation by lead ions in a combined collector flotation system
    Autorzy:
    He, Mingfei
    Li, Shuangke
    Cao, Miao
    Gao, Yude
    Bu, Hao
    Meng, Qingbo
    Powiązania:
    https://bibliotekanauki.pl/articles/1448361.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    tantalum niobium ore
    Pb2+ ions activation
    ammonium dibutyl dithiophosphate
    coadsorption
    Opis:
    The effect of lead ions on the flotation activation of tantalum niobium ore (TNO) was studied by micro-flotation, adsorption capacity experiments, solution chemical composition calculations, and infrared spectral analysis. The experimental demonstrated that the combined collector of salicylhydroxamic acid (SHA) and ammonium dibutyl dithiophosphate (ADDP) resulted in a strong collection capacity for TNO in the presence of lead ions. The solution chemistry calculations determined that the dominant source of lead ions in the aqueous solution was $Pb(OH)^+$ at a pH of 8, which was conducive to the adsorption and interaction of SHA and ADDP anions. In the lead ion activation system, the combined reagent co-adsorbed onto the TNO surface, causing a large negative shift in the zeta potential. The co-adsorption mechanism of the combined collector consisted of complex chemisorption between SHA and the TNO surface active particles, while the main adsorption of ADDP is physisorption.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2021, 57, 1; 29-38
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A new scheme of the environmental classification standards for the bronze cultural relic’s preservation in museums
    Autorzy:
    Li, Dandan
    Zhou, Hao
    Xu, Fangyuan
    Yan, Ying
    Wu, Laiming
    Cai, Lankun
    Powiązania:
    https://bibliotekanauki.pl/articles/28407393.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    QCM
    temperature
    humidity
    indoor exposure
    cultural relics
    mikrowaga kwarcowa
    temperatura
    wilgotność
    ekspozyja w pomieszczeniach
    zabytki kultury
    Opis:
    The environmental risk classification of the metal relics is usually determined by the corrosion rate of the metal but it is difficult to monitor the deterioration of the metal relics directly. A strong relationship exists between indoor exposure, the air quality classification of atmospheric corrosion, and the actual deterioration of metal relics. The copper-silver hanging plate method requires a long period of environmental exposure and has certain hysteresis, thus reflecting the current environmental quality of the museum in real time poses some difficulties. However, the application of the environmental reactivity monitor (ERMs) based on the piezoelectric effect can solve the above problems. The invented quartz crystal microbalance (QCM) reactivity monitoring device is applied to study the influence of temperature and humidity on the corrosion of the bronze-simulated materials and the relationship between the corrosion depth rate of the bronze-simulated materials and the frequency change of the crystal oscillator. Then, the recommended classification range of temperature and humidity and the airquality classification standards for the preservation environment of the bronze cultural relics in museums are proposed.
    Źródło:
    Environment Protection Engineering; 2023, 49, 4; 45--59
    0324-8828
    Pojawia się w:
    Environment Protection Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Prediction of PM2.5 hourly concentrations in Beijing based on machine learning algorithm and ground-based LiDAR
    Autorzy:
    Fang, Zhiyuan
    Yang, Hao
    Li, Cheng
    Cheng, Liangliang
    Zhao, Ming
    Xie, Chenbo
    Powiązania:
    https://bibliotekanauki.pl/articles/2073773.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    PM2.5
    LiDAR
    machine learning
    air pollution monitoring
    Opis:
    The prediction of PM2.5 is important for environmental forecasting and air pollution control. In this study, four machine learning methods, ground-based LiDAR data and meteorological data were used to predict the ground-level PM2.5 concentrations in Beijing. Among the four methods, the random forest (RF) method was the most effective in predicting ground-level PM2.5 concentrations. Compared with BP neural network, support vector machine (SVM), and various linear fitting methods, the accuracy of the RF method was superior by 10%. The method can describe the spatial and temporal variation in PM2.5 concentrations under different meteorological conditions, with low root mean square error (RMSE) and mean square deviation (MD), and the consistency index (IA) reached 99.69%. Under different weather conditions, the hourly variation in PM2.5 concentrations has a good descriptive ability. In this paper, we analyzed the weights of input variables in the RF method, constructed a pollution case to correspond to the relationship between input variables and PM2.5, and analyzed the sources of pollutants via HYSPLIT backward trajectory. This method can study the interaction between PM2.5 and air pollution variables, and provide new ideas for preventing and forecasting air pollution.
    Źródło:
    Archives of Environmental Protection; 2021, 47, 3; 98--107
    2083-4772
    2083-4810
    Pojawia się w:
    Archives of Environmental Protection
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study on the dynamic response of deep-sea trawlers in sea trials
    Autorzy:
    Xu, Qingchao
    Xie, Yonghe
    Cai, Hao
    Gong, Xiwu
    Li, Detang
    Wei, Wang
    Jia, Panpan
    Powiązania:
    https://bibliotekanauki.pl/articles/32917892.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
    Tematy:
    trawler
    automation
    warp tension
    warp length
    ship speed
    Opis:
    The increasing use of automation in fishing vessels has improved trawling efficiency while directly affecting the fishing capacity and cost of fishing vessels. Among the various influencing factors, warp tension and warp length can be varied to automatically balance the retraction and release of warp control. We combined the two parameters and independently designed and developed the key equipment for fishing vessels—the warp dynamometer and meter counter—and control software. The accuracy of the warp tension and length measurements was improved. The designed equipment was applied to sea trials under different working conditions, and the test data records were exported. Next, filtered time-domain graphs of the required parameters were plotted through complex Fourier transform, first-order lowpass filtering, and inverse Fourier transform. The results of data processing using various parameters were compared and analysed to determine the variation trends of the parameters and verify the effects of their balance control. The results indicated that using an automatic balance control system that combines warp tension and warp length can be effective for the fishing operation of offshore double-deck trawlers. In addition, first-order low-pass filtering can be used to filter complex warp tension data. This study also determined the relationship between warp tension and experimental parameters such as warp length and ship speed during the release of control. After the balance control of warp tension and warp length, the net mouth area increased by 30.7% and 36.5%, respectively, and the fishing efficiency of the vessel improved considerably.
    Źródło:
    Polish Maritime Research; 2023, 1; 25-32
    1233-2585
    Pojawia się w:
    Polish Maritime Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    RFID tag group recognition based on motion blur estimation and YOLOv2 improved by Gaussian algorithm
    Autorzy:
    Li, Lin
    Yu, Xiao-Lei
    Liu, Zhen-Lu
    Zhao, Zhi-Min
    Zhang, Ke
    Zhou, Shan-Hao
    Powiązania:
    https://bibliotekanauki.pl/articles/2051852.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    RFID
    YOLOv2
    neural network
    GRNN
    Opis:
    Effective recognition of tags in the dynamic measurement system would significantly improve the reading performance of the tag group, but the blurred outline and appearance of tag images captured in motion seriously limit the effectiveness of the existing tag group recognition. Thus, this paper proposes passive tag group recognition in the dynamic environment based on motion blur estimation and improved YOLOv2. Firstly, blur angles are estimated with a Gabor filter, and blur lengths are estimated through nonlinear modelling of a Generalized Regression Neural Network (GRNN). Secondly, tag recognition based on YOLOv2 improved by a Gaussian algorithm is proposed. The features of the tag group are analyzed by the Gaussian algorithm, the region of interest of the dynamic tag is effectively framed, and the tag foreground is extracted; Secondly, the data set of tag groups are trained by the end-to-end YOLOv2 algorithm for secondary screening and recognition, and finally the specific locations of tags are framed to meet the effective identification of tag groups in different scenes. A considerable number of experiments illustrate that the fusion algorithm can significantly improve recognition accuracy. Combined with the reading distance, the research presented in this paper can more accurately optimize the three-dimensional structure of the tag group, improve the reading performance of the tag group, and avoid the interference and collision of tags in the communication channel. Compared with the previous template matching algorithm, the tag group recognition ability put forward in this paper is improved by at least 13.9%, and its reading performance is improved by at least 6.2% as shown in many experiments.
    Źródło:
    Metrology and Measurement Systems; 2022, 29, 1; 53-74
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of the degree of polymerization of nonylphenol polyoxyethylene ether on the dewatering of low-rank coal
    Autorzy:
    Li, Lin
    He, Meng
    Liu, Mingpu
    Lin, Mengyu
    Hu, Shanpei
    Yu, Hao
    Wang, Qingbiao
    You, Xiaofang
    Powiązania:
    https://bibliotekanauki.pl/articles/1449205.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    low-rank coal
    NPEO
    dewatering
    adsorption
    long-flame coal
    Opis:
    In this study, we investigated the effect of the hydrophilic ethylene oxide chain lengths (i.e., degree of polymerization) of nonylphenol polyoxyethylene ether (NPEO-x, x = 8, 10, and 12) on the dewatering of low-rank coal slime through dewatering and adsorption experiments and X-ray photoelectron spectroscopy (XPS) measurements. The dewatering experiments showed that the adsorption of NPEO changed the water content of the low-rank coal slime: NPEO-8 achieved the best effect, followed, in decreasing order, by NPEO-10 and NPEO-12. Adsorption experiments revealed that the adsorption isotherms of NPEO-x on the low-rank coal surface conform with the Langmuir model, and its adsorption kinetics follow the pseudo-second-order kinetic equation. Furthermore, the adsorption is a spontaneous process and controlled by both intraparticle diffusion and liquid film diffusion. The XPS results showed that the adsorption of NPEO-x decreased the content of oxygencontaining groups and, thus, improved the hydrophobicity of the low-rank coal surface. Further, the use of NPEO-x with a low degree of polymerization (x = 8) improves the hydrophobicity of the coal surface and decreases the water content of low-rank coal slime.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2020, 56, 4; 723-736
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Polymorphisms in the p53 pathway genes and micronucleus occurrence in Chinese vinyl chloride-exposed workers
    Autorzy:
    Li, Yong
    Feng, Nan-Nan
    Zhang, Guang-Hui
    Wang, Qi
    Hao, Yan-Hui
    Nanzhang, Ya
    Long, Changxu
    Li, Yongliang
    Brandt-Rauf, Paul W.
    Xia, Zhao-Lin
    Powiązania:
    https://bibliotekanauki.pl/articles/2179059.pdf
    Data publikacji:
    2013-12-01
    Wydawca:
    Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
    Tematy:
    VC
    occupational exposure
    p53 pathway genes
    genetic polymorphism
    Opis:
    Objectives: To investigate the association between polymorphisms in the p53 pathway genes and chromosomal damage in vinyl chloride (VC)-exposed workers. Materials and Methods: Cytokinesis block micronucleus test was performed in 310 VC-exposed workers and 149 non-exposed workers to determine chromosomal damage. The polymerase chain reaction and restriction fragment length polymorphism technique were used to detect six SNPs in the p53 pathway genes involved in the cell cycle. Results: There was a highly significant dose-response relationship between VC exposure and chromosomal damage. Individuals carrying the variant genotypes were at higher risk for chromosomal damage compared with their wild type genotype: p53rs1042522, MDM2 Del1518rs3730485, MDM2rs2279744 and GADD45Ars532446. On the other hand, individuals possessing the variant genotype of CDKN2A rs3088440 had significantly decreased risk compared with the corresponding wild-type. Conclusions: Genetic polymorphisms in P53 pathway genes may have an impact on VC-induced chromosomal damage.
    Źródło:
    International Journal of Occupational Medicine and Environmental Health; 2013, 26, 6; 825-836
    1232-1087
    1896-494X
    Pojawia się w:
    International Journal of Occupational Medicine and Environmental Health
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Adsorption of hydrated Fe(OH)2+ on the kaolinite surface: A density functional theory study
    Autorzy:
    Wu, Hongqiang
    Miao, Yuqi
    Long, Qibang
    Yan, Huashan
    Li, Yong
    Qiu, Sen
    Wu, Hao
    Zhao, Guanfei
    Qiu, Tingsheng
    Powiązania:
    https://bibliotekanauki.pl/articles/27323639.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    kaolinite
    adsorption
    Fe
    density functional theory
    Opis:
    The present study employed density functional theory (DFT) to analyze the adsorption configuration and mechanism of Fe(OH)2+ on the kaolinite (001) surface. The findings demonstrated that Fe(OH)2(H2O)4+ is the main type in which hydrated Fe(OH)2+ can be found in aqueous solution. On the surface of kaolinite, Fe(OH)2(H2O)4+ will be adsorbed. There are two forms of adsorption: outer-sphere and inner-sphere coordination (monodentate/bidentate) adsorption. Fe(OH)2(H2O)4+ has a moderate propensity to adsorb on the alumina octahedral sheet of kaolinite when the outer-sphere coordination adsorption takes place. In cases of inner-sphere coordination adsorption, Fe exhibits a tendency to form monodentate adsorption compounds in conjunction with Ou atoms. Additionally, it prefers to create bidentate adsorption compounds through coordination with both Ot and Ou atoms. The adsorption mechanism analysis results show that the ionic property of Fe atom decreases after outer-sphere coordination adsorption. After inner-sphere coordination adsorption, some electrons of Fe atom are transferred to the surface O atom. The presence of electrons between the Fe and O atoms enhances the formation of bonds, hence enhancing the covalent nature of the Fe-O bond. Theoretical FT-IR (Fourier transform infrared spectroscopy) calculations show that the formation of Fe-O chemical bonds. Because of the lower adsorption energy and more chemical bonds, hydrate Fe(OH)2+ is more likely to be bidentate adsorbed on the kaolinite surface.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2023, 59, 6; art. no. 174415
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-32 z 32

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies