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Mechanical model for double side self-propelled rolling machine based on rigid and flexible contact dynamics

International Journal of Agricultural and Biological Engineering 2022年第6期15卷 38-43页

作者： Yiming Li Yu Liu xiang yue Zhongqiu Li Xing'an Liu Tianlai Li College of Engineering Shenyang Agricultural UniversityShenyang 110866China College of Horticulture Shenyang Agricultural UniversityShenyang 110866China Key Laboratory of Protected Horticulture Shenyang Agricultural UniversityMinistry of EducationShenyang 110866China National&Local Joint Engineering Research Center of Northern Horticultural Facilities Design&Application Technology(Liaoning) Shenyang 110866China

The objective of the present research was to establish a mechanical model to study the performance of double side self-propelled rolling *** are two key models in the modeling *** first model is the soft cover dynamics model,which is an important innovation in this *** the insulation quilt was established based on the Macro-modeling *** second model is the double side self-propelled rolling machine virtual prototype *** specifying multiple contact constraints and loadings between the soft cover dynamics model and the rigid component,the virtual prototype model was built successfully and the double side self-propelled rolling process was completely ***,the interaction mechanisms of the rigid and flexible coupling mechanics were *** virtual rolling processes of different insulation quilt lengths were analyzed under different thickness *** simulated results showed a good agreement with the experimental measurements,which suggested that the established model is an effective approach to evaluating and optimizing the rolling *** successful establishment of the mechanical model can facilitate the study of the performance of the product and further optimization,and also is of great significance to shorten the development cycle and reduce costs.

关键词： contact dynamics solar greenhouse self-propelled rolling machine mechanical model

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Effects of Shear Fracture on In-depth Profile Modification of Weak Gels

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Petroleum Science 2007年第1期4卷 55-60页

作者： Li Xianjie Song Xinwang yue xiang＇an Hou Jirui Fang Lichun Zhang Huazhen Center for Enhanced Oil Recovery China University of Petroleum Beijing 102249 China Research Institute of Geological Science Shengli Oilfield Company Ltd. Sinopec Dongying Shandong 257015 China

Two sand packs were filled with fine glass beads and quartz sand respectively. The characteristics of crosslinked polymer flowing through the sand packs as well as the influence of shear fracture of porous media on the indepth profile modification of the weak gel generated from the crosslinked polymer were investigated. The results indicated that under the dynamic condition crosslinking reaction happened in both sand packs, and the weak gels in these two cases became small gel particles after water flooding. The differences were： the dynamic gelation time in the quartz sand pack was longer than that in the glass bead pack. Residual resistance factor （FRR） caused by the weak gel in the quartz sand pack was smaller than that in the glass bead pack. The weak gel became gel particles after being scoured by subsequent flood water. A weak gel with uniform apparent viscosity and sealing characteristics was generated in every part of the glass bead pack, which could not only move deeply into the sand pack but also seal the high capacity channels again when it reached the deep part. The weak gel performed in-depth profile modification in the glass bead pack, while in the quartz sand pack, the weak gel was concentrated with 100 cm from the entrance of the sand pack. When propelled by the subsequent flood water, the weak gel could move towards the deep part of the sand pack but then became tiny gel particles and could not effectively seal the high capacity channels there. The in-depth profile modification of the weak gel was very weak in the quartz sand pack. It was the shear fracture of porous media that mainly affected the properties and weakened the in-depth profile modification of the weak gel.

关键词： Weak gel shear fracture in-depth profile modification glass bead pack quartz sand pack

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Chimera states in Gaussian coupled map lattices

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Frontiers of physics 2018年第2期13卷 39-42页

作者： Xiao-Wen Li Ran Bi yue-xiang Sun Shuo Zhang Qian-Qian Song Department of Physics Beijing Normal University Beijing 100875 China

We study chimera states in one-dimensional and two-dimensional Gaussian coupled map lattices through simulations and experiments. Similar to the case of global coupling oscillators, individual lattices can be regarded as being controlled by a common mean field. A space-dependent order pa- rameter is derived from a self-consistency condition in order to represent the collective state.

关键词： chimera state coupled map lattices nonlocal coupling

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Common causes of geriatric medical emergencies in China

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Journal of Geriatric Cardiology 2015年第1期12卷 91-92页

作者： Hong-Wei Liu Li-Na Han yue-xiang Zhao Wei Zhang Department of Cardiovascular Disease South Building of PLA General Hospital Beijing 100853 China.

To the Editor One of the most significant demographic changes in our cotmtry is the increase in the elderly population. In China Mainland, the population aged 60 and older was 194 million in 2012, accounting for 14.3% of the total population. However, by 2053, it is estimated that the number of elderly will reach 487 million, representing 34.8% of the total population. Elderly patients represent an everncreasing populace in emergency medicine who often present with atypical signs and symptoms as well as eomorbidities that can complicate diagnoses and *** The geographic factors and the developmental status of the country can influence the spectrum of common geriatric emergencies. Thus, this study presents a retrospective analysis of common causes of geriatric emergencies involving 9,628 elderly patients from Jan. 2008 to Dec. 2013 in an emergency department in Beijing, China.

关键词： China Comorbidity Emergency medicine The elderly

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Effect of anti-VEGF treatment on retinopathy of prematurity in Zone Ⅱ Stage 3^+

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International Journal of Ophthalmology(English edition) 2018年第4期11卷 641-644页

作者： Xiu-Mei Yang yue-xiang Zhao Zong-Hua Wang Lu Liu Department of Ophthalmology PLA Army General Hospital Department of Cardiology Nanlou Clinical Division of Chinese PLA General Hospital

AIM： To evaluate the effect of intravitreal ranibizumab injection for retinopathy of prematurity（ROP） in Zone Ⅱ Stage 3^＋.METHODS： Data was collected for ROP patients with Zone Ⅱ Stage 3^＋ who received intravitreal ranibizumab injections between October 2014 and Janu ary 2017 at the Department of Ophthalmology in our hospital. No prior laser or other intravitreal treatment was done. Prior to the intervention and at each follow-up visit, fundus examination was performed. Gestational age at birth, sex, birth weight, ROP zone, ROP stage, post menstrual age（PMA） at treatment, and follow-up pe riod were recorded. The final clinical status of the retina was evaluated for each patient. The primary outcome mea sures included ROP recurrences requiring re-treatment, complete or incomplete peripheral ***： Eighty-six eyes of 46 premature infants with Zone Ⅱ Stage 3~＋ ROP were enrolled in the study. The mean gestational age at birth was 28.18±1.67（range： 25 to 33）wk and the mean birth weight was 1070.57±226.85（range： 720.00 to 1650.00） g. The mean PMA at treatment was 38.32±2.99（range： 32.29 to 46.00）wk. Seventy-one eyes（82.56%） were treated success fully with intravitreal ranibizumab as monotherapy. Fifteen eyes（17.44%） developed recurrent disease. The mean interval between the treatment and retreatment was 5.96±3.22（range： 1.86 to 11.71）wk. All eyes vascularized into zone Ⅲ at the end of the study and among them 62 eyes（72.09%） achieved complete vascu ***： Intravitreal ranibizumab injection is an effective treatment in Zone Ⅱ Stage 3^＋ ROP patients. More patients with longer follow-up duration are necessary to confirm the safety and efficacy of this treatment.

关键词： retinopathy of prematurity ranibizumab plus disease

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J-clean and Strongly J-clean Rings

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Communications in Mathematical Research 2018年第3期34卷 241-252页

作者： xiang yue-MING OUYANG LUN-QUN School of Mathematics and Computational Science Huaihua University Department of Mathematics Hunan University of Science and Technology

Let R be a ring and J（R） the Jacobson radical. An element a of R is called（strongly） J-clean if there is an idempotent e ∈ R and w ∈ J（R） such that a = e ＋ w（and ew = we）. The ring R is called a（strongly） J-clean ring provided that every one of its elements is（strongly） J-clean. We discuss, in the present paper,some properties of J-clean rings and strongly J-clean rings. Moreover, we investigate J-cleanness and strongly J-cleanness of generalized matrix rings. Some known results are also extended.

关键词： J-cleanring strongly J-cleanring generalized matrix ring

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PS-injective Modules, PS-flat Modules and PS-coherent Rings

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Communications in Mathematical Research 2013年第2期29卷 121-130页

作者： xiang yue-ming Du Xian-kun Department of Mathematics and Applied Mathematics Huaihua University

A left ideal I of a ring R is small in case for every proper left ideal K of R, K ＋ I ≠R. A ring R is called left PS-coherent if every principally small left ideal Ra is finitely presented. We develop, in this paper, PS-coherent rings as a generalization of P-coherent rings and J-coherent rings. To characterize PS-coherent rings, we first introduce PS-injective and PS-flat modules, and discuss the relation between them over some spacial rings. Some properties of left PS-coherent rings are also studied.

关键词： PS-injective module PS-flat module PS-coherent ring

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Effects of time lag and stress loading rate on permeability in low permeability reservoirs

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Mining Science and Technology 2009年第4期19卷 526-530页

作者： WANG Rui yue xiang-an ZHANG Wei TAN Xi-qun ZHANG Yan MOE Key Laboratory for Petroleum Engineering China University of Petroleum Beijing 102249 China Sinopec Exploration ＆ Production Research Institute Beijing 100083 China China Huayou Group Corporation Beijing 100011 China

In order to study the effect of time lag and stress loading rates on rock deformation,the conventional stepped stress loading mode was changed into a continuous mode to investigate the effect of effective pressure on permeability and *** time lag effect of rock deformation illustrating the relationship between changes in permeability and steady time was *** reduction ratios were measured under different stress loading rates which were achieved by different pump rate *** results show that permeability and porosity gradually decrease with increases in effective *** at high effective pressure attains stability *** times at low effective pressure are very *** in permeability at lower stress loading rates is small,while,in contrast,it is large at high stress loading rates.

关键词： low permeability stress sensitivity time lag effect stress loading rate

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不同消融指数指导下高功率短时程射频消融术对心房颤动患者超声心动图和并发症及术后复发的影响

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中国心血管病研究 2024年第8期22卷 757-762页

作者：唐亮张进鹏陈月祥吴妙敏河源市人民医院心血管内科广东省河源市517000

目的探究不同消融指数(AI)指导下高功率短时程射频消融(HPSD)术对心房颤动(AF)患者超声心动图、并发症及术后复发的影响。方法选取2019年11月~2023年10月河源市人民医院行射频导管消融治疗的80例AF患者,采用随机数字表法分为低AI组和高A... 详细信息

目的探究不同消融指数(AI)指导下高功率短时程射频消融(HPSD)术对心房颤动(AF)患者超声心动图、并发症及术后复发的影响。方法选取2019年11月~2023年10月河源市人民医院行射频导管消融治疗的80例AF患者,采用随机数字表法分为低AI组和高AI组,各40例。2组均行AI指导下HPSD消融术治疗,低AI组消融的目标AI为前壁350~400,后壁320~350,高AI组消融的目标AI为前壁450~500,后壁350~400。比较2组围术期指标、消融效果[肺静脉隔离(PVI)情况、PVI单圈隔离率]、术中气爆(POP)声发生率、手术前后超声心动图指标[左心室射血分数(LVEF)、左心室收缩末期内径(LVESD)、左心室舒张末期内径(LVEDD)、E/A比值]、复发相关标志物[可溶性生长刺激表达基因2(sST2)、尿酸(UA)、成纤维细胞生长因子-23(FGF-23)]水平、围术期严重并发症发生率、近期复发情况。结果高AI组每点消融时间、PVI时间、左心房操作时间、手术时间均短于低AI组的[(13.42±1.28)min比(15.67±1.76)min,(26.58±3.19)min比(29.24±2.42)min,(4.37±1.25)min比(5.16±1.38)min,(121.67±20.35)min比(132.48±22.19)min,P0.05);术后高AI组LVEF高于低AI组[(69.32±2.15)%比(68.01±2.27)%,P0.05)。结论高AI指导下HPSD消融术治疗AF患者,能优化手术流程,增强PVI隔离效果,促进心功能恢复,抑制复发标志物表达,但近期效果及安全性与低AI相当。

关键词：心房颤动消融术消融指数高功率短时程超声心动图并发症复发

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Effect of Top Slag Basicity on Quality of Steel Treated by Exothermic Agent SiFe and SiCaBa during Chemical Heating

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Journal of Iron and Steel Research International 2002年第1期9卷 12-15页

作者： WANG Hai-chuan ZHOU Yun WANG Shi-jun yue Ke-xiang DONG Yuan-chi Anhui University of Technology

The effect of top slag basicity on quality of steel treated with SiFe and SiCaBa alloy as exothermic agent in chemical heating was *** experiments were carried out in MoSi_2 laboratory furnace with 0.2 kg molten steel for equilibrium test and 2 kg molten steel for simulation test *** results showed that the adjusting basicity of top slag with CaO is effective to prevent rephosphorization and resulphurization,and it is possible to dephosphorize and desulphurize and remove the inclusions from molten steel when basicity R of the top slag is adjusted to 2.0 — 3.10,and SiCaBa alloy is better than SiFe alloy in this relation.

关键词： chemical heating top slag basicity SiFe SiCaBa exothermic agent

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