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Wyświetlanie 1-15 z 19
Tytuł:
Risk sharing markets and hedging a loan portfolio: a note.
Autorzy:
Broll, Udo
Guo, Xu
Welzel, Peter
Powiązania:
https://bibliotekanauki.pl/articles/943134.pdf
Data publikacji:
2017-12-20
Wydawca:
Uniwersytet Ekonomiczny w Poznaniu
Tematy:
risk management
credit risk
loan portfolio
derivatives
hedging effectiveness
Opis:
Our study features a financial institute facing credit risk. Hedging credit risk by offsetting an open position with an opposite one in the financial market is important for financial intermediaries, which are concerned with both the profitability and risk of their operations. As risk management is crucial for the financial institute, the issues of how it is optimally determined and how it adjusts to changes in the financial environment deserve closer scrutiny. We extend the analysis of hedging with financial instruments against credit risk to the case of multiple types of credit risk. We show that standard results on the optimal hedge ratio and risk management effectiveness in the case of one single source of credit risk to carry over a loan portfolio in a non-trivial but intuitive way. While we focus on credit risk and credit derivatives, our analysis can be easily applied to other financial assets, which can be traded in futures market.
Źródło:
Economics and Business Review; 2017, 3(17), 4; 47-54
2392-1641
Pojawia się w:
Economics and Business Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acer truncatum seedlings are more plastic than Quercus variabilis seedlings in response to different light regimes
Autorzy:
Guo, X.
Wang, R.-Q.
Wang, C.D.
Xu, F.
Zhao, S.
Guo, W.-H.
Powiązania:
https://bibliotekanauki.pl/articles/41339.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Acer truncatum
seedling
Quercus variabilis
Chinese cork oak
plant response
light regime
irradiance acclimation
chlorophyll fluorescence
morphology
photoinhibition
Opis:
In this study, we investigated responses of the mid-successional species Acer truncatum Bunge and the late-successional species Quercus variabilis Blume to three solar illumination conditions: (1) constant low light (CL), (2) constant high light (CH) and (3) low light first and high light afterwards (LH). The last treatment was to simulate a canopy opening. Both species exhibited increases in biomass, totally and in part, and decreases in leaf water content, specific leaf area and chlorophyll concentrations in LH treatment compared to CL treatment. For A. truncatum, exposure to high light condition (LH) increased crown area, and decreased root to shoot ratio, stem mass ratio and leaf perimeter. However, for Q. variabilis, LH treatment increased stem diameter at ground height, effective quantum yield, photochemical quenching and decreased maximum photosystem II quantum yield. The biomass allocation pattern did not change in Q. variabilis among three light conditions. With respect to newly developed leaves, no significant differences were found in leaf size of Q. variabilis between LH treatment and CH treatment while that of A. truncatum decreased in LH treatment. All chlorophyll fluorescence parameters in newly developed oak leaves in LH treatment increased compared to those of CH treatment while no difference was found for A. truncatum between LH and CH treatment. A. truncatum displayed a greater overall plasticity than Q. variabilis although the oak seedlings have a greater plasticity with respect to chlorophyll concentration and chlorophyll fluorescence parameters. A. truncatum should be a better candidate for vegetation recovery, especially in places with heterogeneous light conditions.
Źródło:
Dendrobiology; 2016, 76
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hierarchy of plasticity traits in responses of Quercus aliena to light conditions and water availability
Autorzy:
Xu, N.
Wang, R.
Liu, J.
Lu, P.
Guo, W.
Powiązania:
https://bibliotekanauki.pl/articles/41404.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Opis:
This study aimed to investigate plasticity of different plant traits to varied light and water availability. A greenhouse experiment was conducted with Quercus aliena seedlings with two light and four soil water levels. Plant traits related to leaf physiology, morphology, anatomy, and biomass production were determined. The results showed that plant size had significant effects on leaf area, leaf number, shoot height, basal diameter and crown area. After excluding the influence of plant size, water treatment had stronger effects on plants compared to light levels, and their interaction effect was significant. The limited water supply significantly inhibited leaf photosynthetic rate and the fluorescence efficiency under high light. However, leaves submitted to moderate drought stress showed enhanced fluorescence activity under shade condition. Grand plasticity of leaf physiology and growth was the highest, followed by biomass allocation and leaf morphology, and lastly anatomy, and this ranking did not change as resources considered. Among the variables, leaf petiole length, chlorophyll content and leaf area could be selected as candidates for estimation of species’ plasticity to water, light and their interaction, respectively. Therefore, our results suggested that there was a hierarchy existing among traits plasticity in Q. aliena, and supported the aboveground facilitation hypothesis that shade could alleviate the adverse effect of drought.
Źródło:
Dendrobiology; 2015, 74
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A numerical simulation method for a repairable dynamic fault tree
Autorzy:
Xu, Zhixin
Guo, Dingqing
Wang, Jinkai
Li, Xueli
Ge, Daochuan
Powiązania:
https://bibliotekanauki.pl/articles/1841835.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
repairable dynamic fault tree
numerical simulation
Monte Carlo
sequential failure region
minimal cut sequence set
Opis:
Dynamic fault trees are important tools for modeling systems with sequence failure behaviors. The Markov chain state space method is the only analytical approach for a repairable dynamic fault tree (DFT). However, this method suffers from state space explosion, and is not suitable for analyzing a large scale repairable DFT. Furthermore, the Markov chain state space method requires the components’ time-to-failure to follow exponential distributions, which limits its application. In this study, motivated to efficiently analyze a repairable DFT, a Monte Carlo simulation method based on the coupling of minimal cut sequence set (MCSS) and its sequential failure region (SFR) is proposed. To validate the proposed method, a numerical case was studied. The results demonstrated that our proposed approach was more efficient than other methods and applicable for repairable DFTs with arbitrary time-to-failure distributed components. In contrast to the Markov chain state space method, the proposed method is straightforward, simple and efficient.
Źródło:
Eksploatacja i Niezawodność; 2021, 23, 1; 34-41
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recovery of nickel and iron from low–grade laterite ore and red mud using co–reduction roasting: Industrial-scale test
Autorzy:
Guo, Xiaoshuang
Xu, Chengyan
Wang, Yingshuo
Li, Xiaohui
Sun, Tichang
Powiązania:
https://bibliotekanauki.pl/articles/1447175.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
co-reduction
low-grade laterite ore
red mud
rotary kiln
powdered ferronicke
Opis:
In this study, the effects of red mud (RM) dosage during the co-reduction roasting of lowgrade laterite ore and RM were investigated. The expanded test was conducted under the following optimized conditions: RM-1 dosage of 15 wt%, anthracite dosage of 13 wt%, a roasting temperature of 1300oC, and roasting time of 3 h. Ferronickel powder was obtained with a nickel grade of 1.95 wt%, iron grade of 83.25 wt%, and nickel and total iron recoveries of 94.71 wt% and 95.98 wt%, respectively. The addition of RM improved the recovery of nickel and total iron in ferronickel powder. The reason was because of the increased intensity of the diffraction peaks of kamacite and iron, and the ferronickel particles grown due to the liquid phase were easier to achieve at a lower melting point. The industrialscale test results showed that ferronickel powder was obtained with average nickel and total iron grades of 1.76 wt% and 86.46 wt%, respectively, which indicated the successful industrial-scale test of co–reduction roasting. Thermodynamic analysis theoretically illustrated the feasibility of the co–reduction of low-grade laterite ore and RM. Increased roasting temperature promoted the reduction of iron oxide and nickel oxide.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 3; 61-72
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A model-free direct predictive grid-current control strategy for grid-connected converter with an inductance-capacitance-inductance filter
Autorzy:
Guo, Leilei
Zheng, Mingzhe
Yu, Changzhou
Xu, Haizhen
Li, Yanyan
Powiązania:
https://bibliotekanauki.pl/articles/2202543.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
grid-connected converter
GCC
model-free predictive current control
MFPCC
parameter mismatch
robustness
Opis:
The disadvantages of the conventional model predictive current control method for the grid-connected converter (GCC) with an inductance-capacitance-inductance (LCL) filter are a large amount of calculation and poor parameter robustness. Once parameters of the model are mismatched, the control accuracy of model predictive control (MPC) will be reduced, which will seriously affect the power quality of the GCC. The article intuitively analyzes the sensitivity of parameter mismatch on the current predictive control of the conventional LCL-filtered GCC. In order to solve these issues, a model-free predictive current control (MFPCC) method for the LCL-filtered GCC is proposed in this paper. The contribution of this work is that a novel current predictive robust controller for the LCL-filtered GCC is designed based on the principle of the ultra-local model of a single input single output system. The proposed control method does not require using any model parameters in the controller, which can effectively suppress the disturbances of the uncertain parameter variations. Compared with conventional MPC, the proposed MFPCC has smaller current total harmonic distortion (THD). When the filter parameters are mismatched, the control error of the proposed method is smaller. Finally, a comparative experimental study is carried out on the platform of Typhoon and PE-Expert4 to verify the superiority and effectiveness of the proposed MFPCC method for the LCL-filtered GCC.
Źródło:
Archives of Electrical Engineering; 2023, 72, 1; 23--42
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental study on shear mechanical properties of cement mortar specimen with through-step joints under direct shear
Autorzy:
Xiong, Liangxiao
Chen, Haijun
Guo, Haogang
Mei, Songhua
Xu, Zhongyuan
Liu, Bin
Powiązania:
https://bibliotekanauki.pl/articles/2174090.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
In this study, direct shear tests were carried out on cement mortar specimens with single-ladder, single-rectangular, and double-rectangular step joints. Consequently, the shear strength, and crack shape of specimens with these through-step joints were analyzed, for understanding the influence of the through-step joint’s shape on the direct shear mechanical properties. The results of the investigation are as follows: (1) Under the same normal stress, any increases in the height h of the step joint causes an initial-increase-decrease in the shear strengths of specimens with single-ladder and double-rectangular step joints, causing a type-W variation pattern for the specimens with single-rectangular step joint. More essentially, when normal stress and h are constant, the shear strength of specimens with a single-ladder step joint is the greatest, followed by specimens with a double-rectangular step joint, and then specimens with a single-rectangular step joint is the least. (2) Furthermore, given a small h and low normal stress, specimen with a single-ladder step joint mainly experiences shear failure, whereas specimens with single-rectangular and double-rectangular step joints mainly generate extrusion milling in the step joints.
Źródło:
Archives of Civil Engineering; 2022, 68, 4; 45--61
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the Mechanism and Kinetics of Polymorphic Transitions of ε CL-20 in Composite Systems
Autorzy:
Guo, X.-Y.
Zhang, P.
Xu, J.-J.
Wang, Z.-H.
Jiao, Q.-J.
Powiązania:
https://bibliotekanauki.pl/articles/358032.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
polymorphic transition
kinetics
activation energy
transition temperature
Opis:
In order to explore the polymorphic transition law for ε-CL-20 in composite systems, the polymorphic transition process of pure ε-CL-20 crystals stimulated by heat was investigated by the X-ray Diffraction (XRD) method, and the kinetic parameters of the polymorphic transition process were calculated (including the apparent activation energy Ea and the pre-exponential factor lnA). Meanwhile the effects of different additives on the polymorphic transition process and kinetics of ε-CL-20 were explored in detail. The experimental results showed that the ε-form tends to transform into the γ- form on heating and that the Ea and lnA for the transition process were 209.97 kJ/mol and 57.47, respectively. The first group of additives clearly promoted the polymorphic transition of ε-CL-20 and lowered the initial transition temperature and the activation energy. The second and third groups of additives inhibited the polymorphic transition of ε-CL-20 and raised the initial transition temperature and the activation energy.
Źródło:
Central European Journal of Energetic Materials; 2015, 12, 4; 689-702
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vehicle emission computation through microscopic traffic simulation calibrated using genetic algorithm
Autorzy:
Wei, Yun
Yu, Ying
Xu, Lifeng
Huang, Wei
Guo, Jianhua
Wan, Ying
Cao, Jinde
Powiązania:
https://bibliotekanauki.pl/articles/91529.pdf
Data publikacji:
2019
Wydawca:
Społeczna Akademia Nauk w Łodzi. Polskie Towarzystwo Sieci Neuronowych
Tematy:
environment protection
microscopic traffic simulation
genetic algorithm
IVE model
emission evaluation
Opis:
Vehicle emission calculation is critical for evaluating motor vehicle related environmental protection policies. Currently, many studies calculate vehicle emissions from integrating the microscopic traffic simulation model and the vehicle emission model. However, conventionally vehicle emission models are presented as a stand-alone software, requiring a laborious processing of the simulated second-by-second vehicle activity data. This is inefficient, in particular, when multiple runs of vehicle emission calculations are needed. Therefore, an integrated vehicle emission computation system is proposed around a microscopic traffic simulation model. In doing so, the relational database technique is used to store the simulated traffic activity data, and these data are used in emission computation through a built-in emission computation module developed based on the IVE model. In order to ensure the validity of the simulated vehicle activity data, the simulation model is calibrated using the genetic algorithm. The proposed system was implemented for a central urban region of Nanjing city. Hourly vehicle emissions of three types of vehicles were computed using the proposed system for the afternoon peak period, and the results were compared with those computed directly from the IVE software with a trivial difference in the results from the proposed system and the IVE software, indicating the validity of the proposed system. In addition, it was found for the study region that passenger cars are critical for controlling CO, buses are critical for controlling CO and VOC, and trucks are critical for controlling NOx and CO2. Future work is to test the proposed system in more traffic management and control strategies, and more vehicle emission models are to be incorporated in the system.
Źródło:
Journal of Artificial Intelligence and Soft Computing Research; 2019, 9, 1; 67-80
2083-2567
2449-6499
Pojawia się w:
Journal of Artificial Intelligence and Soft Computing Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of α-damascone
Autorzy:
Hu, Junyi
Guo, Aiqiang
Xu, Yingqian
Pan, Changsheng
Wei, Xingfu
Wang, Longlong
Xiao, Guoyong
Powiązania:
https://bibliotekanauki.pl/articles/778611.pdf
Data publikacji:
2019
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
α-damascone
α-ionone
preparation
Opis:
α-Damascone is widely used in perfumes. However, the manufacture of α-damascone remains challenging owing to the limitations of current production processes. Herein, α-damascone was successfully synthesized from α-ionone using a new route involving only four steps, namely oximization, epoxidation, dehydration, and reduction. The total yield was 54.9% with a final chemical purity of 97% (by GC). Only water, cyclohexane, and ethanol were used in the reactions except in the purification step, and all solvents could be recycled. The structures of the intermediates and target compound were identified by 1H NMR and  13C NMR analyses and MS experiments. This route is a simple and successful method for the industrial preparation of α-damascone.
Źródło:
Polish Journal of Chemical Technology; 2019, 21, 1; 50-51
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model considering residual stiffness and stiffness discontinuity of bolted joints
Autorzy:
Wang, Sheng-Ao
Zhu, Min
Xu, Zi-Jian
Guo, Ming
Li, Biao
Wu, Fei
Powiązania:
https://bibliotekanauki.pl/articles/2087050.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
nonlinear dynamic behaviour
Iwan model
energy dissipation
Opis:
The nonlinear dynamic behavior has an important impact on energy dissipation and vibra- tion damping characteristics of bolted joints. Firstly, the development of tangential dynamic models is summarized and analyzed. Secondly, a five-parameter Iwan model based on a trun- cated power-law distribution is proposed. The backbone and hysteresis curves are obtained. Thirdly, normalized and dimensionless analysis is performed. On the basis of the above, a more concise four-parameter Iwan model with stiffness continuity is proposed. Finally, the validity of the model is verified by comparing the energy dissipation vs excitation force amplitude curve with the experimental data.
Źródło:
Journal of Theoretical and Applied Mechanics; 2022, 60, 1; 63--75
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A flotation combined extraction process for improving the whiteness of phosphogypsum
Autorzy:
Li, Jiangli
Guo, Yongjie
Fan, Peiqiang
Li, Haibin
Chen, Ciyun
Xu, Shuai
Du, Lingpan
Powiązania:
https://bibliotekanauki.pl/articles/24085918.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
phosphogypsum
whiteness
desilication
high-value utilization
floatation
extraction
Opis:
Every year, the production of industrial phosphoric acid generates more than 100 Tg of phosphogypsum (PG), leading to significant environmental damage and the occupation of a vast amount of land space. The urgent need to explore applications for PG has become increasingly apparent. However, impurities such as organic substances, slime, phosphorite, and SiO2 reduce the whiteness of PG, making it difficult to utilize for high-value applications. To address this issue, this study employed a two-stage flotation process to remove the majority of impurities, including SiO2, organic substances, and fine slime adhered to the surface of PG particles. The raw PG sample was first sieved to remove some SiO2 particles. After flotation, sulfuric acid and tributyl phosphate were introduced to decompose the PG particles and remove the impurities wrapped inside. Following this flotation combined extraction process, the whiteness of the PG sample improved from 54.1% to 92.9%, meeting the requirements for building walls and filters.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 3; art. no. 170043
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Palaeo-earthquake events during the late Early Palaeozoic in the central Tarim Basin (NW China): evidence from deep drilling cores
Autorzy:
He, B.
Qiao, X.
Jiao, C.
Xu, Z.
Cai, Z.
Guo, X.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/94300.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
soft-sediment deformation structures
seismites
palaeo-seismicity
Late Ordovician
Silurian
Tazhong 1 Fault
Tarim Basin
struktury deformacji
osady miękkie
sejsmity
ordowik późny
sylur
Kotlina Kaszgarska
Opis:
Various millimetre-, centimetre- and metre-scale soft-sediment deformation structures (SSDS) have been identified in the Upper Ordovician and Lower-Middle Silurian from deep drilling cores in the Tarim Basin (NW China). These structures include liquefied-sand veins, liquefaction-induced breccias, boudinage-like structures, load and diapir- or flame-like structures, dish and mixed-layer structures, hydroplastic convolutions and seismic unconformities. The deformed layers are intercalated by undeformed layers of varying thicknesses that are petrologically and sedimentologically similar to the deformed layers. The SSDS developed in a shelf environment during the early Late Ordovician and formed initially under shear tensile stress conditions, as indicated by boudinage-like structures; during the latest Ordovician, SSDS formed under a compressional regime. The SSDS in the Lower-Middle Silurian consist mainly of mixed layers and sand veins; they formed in shoreline and tidal-flat settings with liquefaction features indicating an origin under a compressional stress regime. By Silurian times, the centre of tectonic activity had shifted to the south-eastern part of the basin. The SSDS occur at different depths in wells that are close to the syn-sedimentary Tazhong 1 Fault (TZ1F) and associated reversed-thrust secondary faults. Based on their characteristics, the inferred formation mechanism and the spatial association with faults, the SSDS are interpreted as seismites. The Tazhong 1 fault was a seismogenic fault during the later Ordovician, whereas the reversed-direction secondary faults became active in the Early-Middle Silurian. Multiple palaeo-earthquake records reflect pulses and cyclicity, which supports secondary tectonic activity within the main tectonic movement. The range of SSDS structures reflects different developments of tectonic activity with time for the various tectonic units of the centralbasin. The effects of the strong palaeo-earthquake activity coincide with uplift, fault activity and syn-tectonic sedimentation in the study area during the Late Ordovician to Middle Silurian.
Źródło:
Geologos; 2014, 20, 2; 105-123
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Teacher stress among public primary and secondary schoolteachers in Datong, a city of Shanxi Province, China: association between teacher stress and standardized workload
Autorzy:
Zhang, Xiaojuan
Guo, Jungang
Ma, Li
Xu, Ruijun
Wang, Jinfang
Yang, Yonghong
Shen, Hong
Powiązania:
https://bibliotekanauki.pl/articles/2203017.pdf
Data publikacji:
2023-05-23
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
stress
occupational health
China
workload
primary and secondary schoolteachers
occupational health strategy
Opis:
Objectives The policy of the standardized workload has been implemented among primary and secondary schoolteachers in Shanxi Province. The aim of this cross-sectional cohort study is to assess teacher stress among primary and secondary schoolteachers in Datong, a city of Shanxi Province and the association between teacher stress and the quantified workload. Material and Methods Three hundred and fifty schoolteachers in 10 public primary schools, 187 schoolteachers in 6 secondary schools and 268 non-teachers in 21 education institutes were recruited. A single-item rating assessment of work-related stress was completed by using the Exposure to Job Stress measure with modification. The quantified workload included class size, teaching hours, and subjects. Descriptive and logistic regression analyses were carried out. Results In 805 participants, the pro- portion of primary and secondary schoolteachers with moderate stress was significantly greater. The results of Spearman’s correlation and logistic regression analyses showed that the occupations of the primary and secondary schoolteachers had higher stress risk. Further, the stratified results showed that among the primary schoolteachers, the independent stress risk factor was larger class size; while among the secondary schoolteachers, the stress associated factor was more weekly teaching hours. Conclusions After standardization of the workload, there remain higher levels of work stress among primary and secondary schoolteachers. Notwithstanding, the stress state in teachers is manageable and they may be faced with controllable stressors.
Źródło:
International Journal of Occupational Medicine and Environmental Health; 2023, 36, 2; 161-176
1232-1087
1896-494X
Pojawia się w:
International Journal of Occupational Medicine and Environmental Health
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of progressive collapse of a super-long span latticed steel arch structure
Autorzy:
Guo, Shuangchao
Xu, Delin
Shang, Kaiguang
Yang, Shuo
Wang, Di
Li, Gen
Zheng, Bing
Jiao, Yong
Powiązania:
https://bibliotekanauki.pl/articles/2200875.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
progressive collapse
steel arch truss structure
compression instability
Opis:
The progressive collapse of a space grid structure which has a large number of members and a large span is the focus of current research. Before the progressive collapse of the structure, there is a problem of instability of the members. In this paper, dynamic nonlinear analysis of a super-long span latticed steel arch structure is carried out to study its progressive collapse process using a Kinematic Hardening Plasticity constitutive model compiled by Vumat material subprogram in Abaqus, which takes into account instability of the members. Differences in the dynamic response process of the structure at the collapse moment and the failure sequence of the members using the member stability model and the material failure constitutive model are compared. Compared with the material failure constitutive model, when the member stability constitutive model is used, the proportion of compressive buckling members in the structural failure is higher, and the bearing capacity of the structure is lower when the initial failure occurs. The structure suffers from localized member compressive failure rather than material yielding, which leads to the progressive collapse of the structure.
Źródło:
Journal of Theoretical and Applied Mechanics; 2023, 61, 1; 103--117
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
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