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Pressure and temperature effects resulting from impact onto materials of different reactivity
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作者 Andreas Heine Matthias Wickert 《Defence Technology(防务技术)》 2025年第2期221-230,共10页
The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurrin... The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurring phenomenology as well as quantitative statements about the relative effects sizes as a function of target material and threat.The considered target materials are steel,aluminum,and magnesium.As threats,kinetic energy penetrator,explosively formed projectile,and shaped charge jet are used.For the investigated combinations,the measured overpressures vary by a factor of up to 5 for a variation of the material,by a factor of up to 7 for a variation of the threat,and by a factor larger than 15for a simultaneous variation of both.The obtained results as well as the experimental approach are relevant for the basic understanding of impact effects and risks due to material reactivity.The paper combines two main aims.Firstly,to provide a summary of own prior work in a coherent journal article and,secondly,to review and discuss these earlier results with a new perspective. 展开更多
关键词 Impact effects PRESSURE TEMPERATURE Risk assessment Material reactivity
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Influence of Parenting Care Guidance Combined with Preventive Healthcare on the Effectiveness of Child Family Parenting
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作者 Wei Sun 《Journal of Clinical and Nursing Research》 2025年第8期339-344,共6页
Objective:To explore the impact of parenting care guidance combined with preventive healthcare on child family parenting.Methods:Ninety-two child families were included as research subjects and randomly divided into a... Objective:To explore the impact of parenting care guidance combined with preventive healthcare on child family parenting.Methods:Ninety-two child families were included as research subjects and randomly divided into a control group and an observation group,with 46 cases in each group.The former implemented basic preventive healthcare,while the latter simultaneously carried out parenting care guidance combined with preventive healthcare.The intervention results of the two groups were compared.Results:The observation group had a higher awareness rate of family parenting knowledge and a higher formation rate of healthy behaviors,P<0.05.At the same time,parents’parenting anxiety scores were lower,and family health management ability scores were higher,P<0.05.Moreover,the observation group showed higher scores in children’s social skills,P<0.05.Conclusion:Parenting care guidance combined with preventive healthcare can effectively improve the status of child family parenting,and it is worthy of promotion and application. 展开更多
关键词 Child family parenting Parenting care guidance Preventive healthcare Impact effectiveness
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Numerical Analysis and Verification of the Gas Jet from Aircraft Engines Impacting a Jet Blast Deflector 被引量:4
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作者 Fu-Dong Gao De-Xin Wang +1 位作者 Hai-Dong Wang Ming-Ming Jia 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期127-137,共11页
The process of the gas jet from aircraft engines impacting a jet blast deflector is not only a complex fluid–solid coupling problem that is not easy to compute, but also a safety issue that seriously interferes with ... The process of the gas jet from aircraft engines impacting a jet blast deflector is not only a complex fluid–solid coupling problem that is not easy to compute, but also a safety issue that seriously interferes with flight deck envi?ronment. The computational fluid dynamics(CFD) method is used to simulate numerically the impact e ect of gas jet from aircraft engines on a jet blast deflector by using the Reynolds?averaged Navier?Stokes(RANS) equations and turbulence models. First of all, during the pre?processing of numerical computation, a sub?domains hybrid meshing scheme is adopted to reduce mesh number and improve mesh quality. Then, four di erent turbulence models includ?ing shear?stress transport(SST) k-w, standard k-w, standard k-ε and Reynolds stress model(RSM) are used to compare and verify the correctness of numerical methods for gas jet from a single aircraft engine. The predicted values are in good agreement with the experimental data, and the distribution and regularity of shock wave, velocity, pressure and temperature of a single aircraft engine are got. The results show that SST k?w turbulence model is more suitable for the numerical simulation of compressible viscous gas jet with high prediction accuracy. Finally, the impact e ect of gas jet from two aircraft engines on a jet blast deflector is analyzed based on the above numerical method, not only the flow parameters of gas jet and the interaction regularity between gas jet and the jet blast deflector are got, but also the thermal shock properties and dynamic impact characteristics of gas jet impacting the jet blast deflector are got. So the dangerous activity area of crew and equipments on the flight deck can be predicted qualitatively and quantitatively. The proposed research explores out a correct numerical method for the fluid–solid interaction during the impact process of supersonic gas jet, which provides an e ective technical support for design, thermal ablation and structural damage analysis of a new jet blast deflector. 展开更多
关键词 Aircraft engine Gas jet Computational fluid dynamics Jet blast deflector Impact effect
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Dynamic responses of cable-stayed bridges to vehicular loading including the effects of the local vibration of cables 被引量:7
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作者 He ZHANG Xu XIE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第8期593-604,共12页
Stay cables, the primary load carrying components of cable-stayed bridges (CSBs), are characterised by high flexi-bility which increases with the span of the bridge. This makes stay cables vulnerable to local vibratio... Stay cables, the primary load carrying components of cable-stayed bridges (CSBs), are characterised by high flexi-bility which increases with the span of the bridge. This makes stay cables vulnerable to local vibrations which may have significant effects on the dynamic responses of long-span CSBs. Hence, it is essential to account for these effects in the assessment of the dynamics CSBs. In this paper, the dynamic responses of CSBs under vehicular loads are studied using the finite element method (FEM), while the local vibration of stay cables is analyzed using the substructure method. A case study of a cable-stayed steel bridge with a center span of 448 m demonstrates that stay cables undergo large displacements in the primary mode of the whole bridge although, in general, a cable’s local vibrations are not obvious. The road surface roughness has significant effects on the interaction force between the deck and vehicle but little effect on the global response of the bridge. Load impact factors of the main girder and tower are small, and the impact factors of the tension of cables are larger than those of the displacements of girders and towers. 展开更多
关键词 Cable-stayed bridge(CSB) Vehicular load Local vibration of cable Impact effect
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The Impact of Buzhong Yiqi Decoction Combined with Xuefu Zhuyu Decoction on Cardiac Function and Quality of Life in Patients with Coronary Heart Disease and Heart Failure
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作者 Dein Zhai 《Journal of Clinical and Nursing Research》 2025年第7期346-351,共6页
Objective:To explore the improvement effect of implementing Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction on cardiac function and quality of life of patients during the treatment of coronary heart disease... Objective:To explore the improvement effect of implementing Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction on cardiac function and quality of life of patients during the treatment of coronary heart disease complicated with heart failure.Methods:Eighty cases were included in the study,and they were equally divided into a control group(n=40,treated with basic western medicine)and a study group(n=40,treated with Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction)according to random sampling grouping method.The intervention index results of the two groups were compared.Results:The improvement of cardiac function index,TCM syndrome score,and quality of life in the study group was more prominent,with a statistical value of P<0.05.Conclusion:Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction and conventional western medicine treatment can effectively improve the cardiac function of patients with coronary heart disease complicated with heart failure and enhance their quality of life.It is worthy of clinical promotion and application. 展开更多
关键词 Coronary heart disease Heart failure Buzhong Yiqi Decoction Xuefu Zhuyu Decoction Impact effect
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Dynamic fracture behavior and coupled impact effect of as-cast W-Zr-Ti energetic structural material
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作者 Yuxuan Qi Liang Mao +3 位作者 Chunlan Jiang Guitao Liu Kongxun Zhao Mengchen Zhang 《Defence Technology(防务技术)》 2026年第1期422-435,共14页
This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior... This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior.The specimens exhibit violent chemical reaction during the fracture process under the impact loading,and the size distribution of their residual debris follows Rosin-Rammler model.The dynamic fracture toughness is obtained by the fitting of debris length scale,approximately 1.87 MPa·m~(1/2).Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression,while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact.Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target,leading to the effective ignition of fuel tank.For the brittleness of as-cast W-ZrTi ESM,further study conducted bond-based peridynamic(BB-PD)C++computational code to simulate its fracture behavior during penetration.The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment.This paper explores a novel as-cast metallic ESM,and provides an available numerical avenue to the simulation of brittle energetic fragment. 展开更多
关键词 Energetic structural material Dynamic fracture behavior Coupled impact effect Mechanical property Peridynamics As-cast W-Zr-Ti alloy
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Quantitative Analysis of Frosting Characteristics on the Drip Tray of A Cryogenic Valve for LNG Ships 被引量:1
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作者 BAI Xu CHEN Guan-yu +2 位作者 DU Yue XU Cao CHEN Jia-jing 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期572-585,共14页
Cryogenic valves play a crucial role in the production and transportation of liquefied natural gas(LNG),and are primarily responsible for efficiently controlling the inflow and outflow of LNG and regulating pressure.H... Cryogenic valves play a crucial role in the production and transportation of liquefied natural gas(LNG),and are primarily responsible for efficiently controlling the inflow and outflow of LNG and regulating pressure.However,due to their operation in low-temperature and high-humidity environments,crucial components such as drip trays are susceptible to frosting,which may lead to LNG leakage,thereby causing severe safety incidents.In this study,the user-defined function(UDF)is employed to redevelop Fluent,which integrates the frost growth model with the Eulerian multiphase flow model,to conduct a quantitative analysis of frosting on drip trays of cryogenic valves.The effects of environmental parameters,such as wind speed,ambient temperature,air humidity,and cold surface temperature on the growth of the frost layer were analyzed.This study reveals a limiting wind speed between 1 m/s and 2 m/s.Upon reaching this limit speed,the growth of the frost layer reaches its maximum,and further increases in the wind speed have no significant effect on the growth of the frost layer.Furthermore,the influence of the change in the flow field on droplet impingement and freezing during the growth of the frost layer is considered through the coupling method of the kinematic characteristics of water droplets and the collection coefficient of water droplets.This study identifies the influence of different parameters on the droplet impact efficiency,leading to the modification of the frost layer on the drip tray. 展开更多
关键词 LNG carrier drip tray FROST effective impact coefficient
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Microstructure and Mechanical Properties of Poly (Vinyl Chloride) Modified by Silica Fume /Acrylic Core-Shell Impact Modifier Blends 被引量:2
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作者 黄健 马保国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第5期886-891,共6页
This research explored replacing acrylic core-shell impact modifier (AIM) by silica fume to toughen PVC. 100%, 75%, 50% and 25% of AIM (8 phr) were substituted by silica fume in PVC respectively, and then processe... This research explored replacing acrylic core-shell impact modifier (AIM) by silica fume to toughen PVC. 100%, 75%, 50% and 25% of AIM (8 phr) were substituted by silica fume in PVC respectively, and then processed by dry blending and twin-screw extrusion. Severe silica fume agglomeration was observed by scanning electron microscope (SEM) in the PVC matrix when 8 phr pure silica fume was used and processed by screw speed of 20 rpm. Its tensile strength was thereby reduced by 38% comparing to unmodified PVC. The silica fume was successfully dispersed while the screw speed was slowed down to 10 rpm to give a stronger screw torque and a longer melt residential time in the extruder. The tensile strength was ’recovered’ to a level comparable to unmodified PVC. Impact test were performed on all formulations extruded at 10 rpm screw speed and synergetic toughening effect was found with 50% substitution and it had the impact strength that was comparable to 8 phr pure AIM toughened PVC. 展开更多
关键词 silica fume acrylic impact modifier synergetic effect poly (vinyl chloride) tensile strength impact modification twin screw extrusion
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The Impact of the Integration of Culture and Tourism Industry on the Upgrading of Tourism Industry Performance
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作者 BAI Yan 《Journal of Landscape Research》 2021年第5期93-99,102,共8页
Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The resul... Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The results show that:①The integration level of the two industries is generally low in all provinces and regions,and the regional differences are obvious.The integration degree of the central and eastern regions is generally higher than that of the western regions.②The integration degree of culture and tourism has a significant positive impact on the economic benefits of regional tourism.The influence on the central and eastern regions is greater than that on the western regions.③The level of informatization has a positive moderating effect on the economic benefits of regional tourism caused by the integration of culture and tourism.④Government intervention has a negative moderating effect on the economic benefits of tourism.In addition,the level of regional economic development,accessibility and tourism resource endowment are also significant factors affecting the economic benefits of regional tourism.The results show that promoting the deep integration of culture and tourism,promoting the informatization of tourism and moderate government intervention in the industry are conducive to improving the economic benefits of regional tourism. 展开更多
关键词 Integration of culture and tourism industry Upgrading of tourism industry performance Theoretical hypothesis Impact effect
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Health Management of Patients with Type II Diabetes and its Influence on Chronic Complication
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作者 Jinmin Ren Shoumei Wang +2 位作者 Tongzhen Zhao Junxia Cui Liqiang Wu 《Journal of Clinical and Nursing Research》 2020年第3期107-110,共4页
Objectives:To explore the application of health management in patients with type II diabetes and to analyze and compare the incidence of chronic complications.Methods:the relevant research work was carried out in our ... Objectives:To explore the application of health management in patients with type II diabetes and to analyze and compare the incidence of chronic complications.Methods:the relevant research work was carried out in our hospital.During September 2018 to September 2019,100 patients with type II diabetes were randomly divided into two groups:one group was given routine nursing intervention,the other group was given health management,and they were named control group and experimental group respectively.Each group had 50 patients,the influence of different nursing methods on the incidence of chronic complications in patients was explored.Results:In the one-year followup results,the corresponding complications of patients mainly include cardiovascular disease,kidney disease,cerebrovascular disease,fundus disease and peripheral neuropathy.The incidence of complications in the experimental group is 10.00%,while that in the control group is 32.00%.in comparison,the incidence in the experimental group is lower,and the data difference between the two group is small(P<0.05),which exists significance.Conclusion:The application of health management method in type II diabetes has significant effect,which can reduce the incidence of chronic complications,improve the quality of life of patients,and has positive significance for clinical development. 展开更多
关键词 Type II diabetes Health management Chronic complications Impact effect
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Impact of multipath effects on theoretical accuracy of TOA-based indoor VLC positioning system 被引量:11
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作者 Xuqing Sun Jingyuan Duan +1 位作者 Yonggang Zou Ancun Shi 《Photonics Research》 SCIE EI 2015年第6期296-299,共4页
This paper discusses the time-of-arrival(TOA) based indoor visible light communication(VLC) positioning system in a non-line-of-sight environment. The propagation delay is assumed to be gamma distributed. The generali... This paper discusses the time-of-arrival(TOA) based indoor visible light communication(VLC) positioning system in a non-line-of-sight environment. The propagation delay is assumed to be gamma distributed. The generalized Cramer–Rao lower bound for multipath propagation is derived as the theoretical accuracy limitation. The performance of the positioning system is affected by the shape parameter and the scale parameter of gamma distribution.The influences on positioning accuracy of multipath effects are analyzed through discussing the physical meaning of the gamma distribution parameters. It is concluded that the lower bound of positioning accuracy is attained when variance of the non-line-of-sight propagation-induced path lengths is zero. The simulation result provesthat the theoretical positioning accuracy is in the order of centimeters with the given scenario. 展开更多
关键词 VLC TOA Impact of multipath effects on theoretical accuracy of TOA-based indoor VLC positioning system
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Impact of the self-steepening effect on soliton spectral tunneling in PCF with three zero dispersion wavelengths
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作者 杨华 肖港燕 +4 位作者 赵赛丽 唐志祥 李涛 罗誉培 田雪 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第7期10-14,共5页
This work presents a numerical investigation of the self-steepening(SS) effect on the soliton spectral tunneling(SST) effect in a photonic crystal fiber(PCF) with three zero dispersion wavelengths. Interestingly... This work presents a numerical investigation of the self-steepening(SS) effect on the soliton spectral tunneling(SST) effect in a photonic crystal fiber(PCF) with three zero dispersion wavelengths. Interestingly, the spectral range and flatness can be flexibly tuned by adjusting the SS value. When the SS coefficient increases, the energy between solitons and dispersion waves is redistributed, and the red-shifted soliton forms earlier in the region of long wavelength anomalous dispersion. As a consequence, the SST becomes more obvious. The findings of this work provide interesting insights in regard to the impact of the SST effect on tailored supercontinuum generation. 展开更多
关键词 PCF DW Impact of the self-steepening effect on soliton spectral tunneling in PCF with three zero dispersion wavelengths
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Patient reported outcome of tyrosine kinase inhibitor related side effects and their impact on daily life in Chinese patients with chronic myeloid leukemia in the chronic phase
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作者 于露 《China Medical Abstracts(Internal Medicine)》 2017年第1期56-,共1页
Objective To explore the impact of patient reported outcome of tyrosine kinase inhibitor(TKI)related side effects on daily life in Chinese patients with chronic myceloid leukemia(CML)in the chronic phase(CP).Methods F... Objective To explore the impact of patient reported outcome of tyrosine kinase inhibitor(TKI)related side effects on daily life in Chinese patients with chronic myceloid leukemia(CML)in the chronic phase(CP).Methods From May to November in 2014。 展开更多
关键词 life CML Patient reported outcome of tyrosine kinase inhibitor related side effects and their impact on daily life in Chinese patients with chronic myeloid leukemia in the chronic phase TKI
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