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Recovery of Level Pillar between Open-pit and Underground Mine by Using Underhand Heading Fill Method
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作者 Sijing Cai, Hai Zhao,Shangjun Ying 1) Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083, China 2)Fujia Mine, him Nickel Corporation, Jilin 132311, China 《Journal of University of Science and Technology Beijing》 CSCD 2001年第4期244-247,共4页
The upper part of the Fujia deposit was mined out by open-pit, and the lower part is being mined underground. The level pillar between open-pit and underground mine had a thickness of 24 m, a length of 300 m and a max... The upper part of the Fujia deposit was mined out by open-pit, and the lower part is being mined underground. The level pillar between open-pit and underground mine had a thickness of 24 m, a length of 300 m and a maximum width of 35 in. As the level pillar contained about 5.2 million ton ore of high nickel grade, it was necessary to recover the level pillar. Because of special need of safety, underhand heading cut-and-fill stoping method was used. For the first two layers of heading, the cemented fill materials were a mix of water and high-aluminum-content cement with silicate gelling agent; and for other heading layers, total tailings was added into the fill mix in order to reduce the cement consumption. Finally, the level pillar was recovered successfully. 展开更多
关键词 level pillar underhand heading method fill materials with silicate gelling agent
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Introduction of Several Methods to Control Fusarium Head Blight (FHB)
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作者 张荣 张敏 《中国农学通报》 CSCD 2008年第10期419-426,共8页
Fusarium head blight (FHB) is a worldwide destructive disease of wheat in the warm, semi-humid or humid regions, especially serious in China. The disease not only causes significant losses in yield and reduces grain q... Fusarium head blight (FHB) is a worldwide destructive disease of wheat in the warm, semi-humid or humid regions, especially serious in China. The disease not only causes significant losses in yield and reduces grain quanlity, but also induces toxin to contaminated seeds, which is harmful to the healthy of human and livestocks, So it is important to control it. There are several methods to control Fusarium head blight (FHB). Such as using Crop rotation, Soil cultivation and Fertiliser, biological control, Fungicides control, transgenes, resistance to control Fusarium head blight (FHB). All of these methods gain some effect, but also exist their deficiency. Sometimes crop rotation had no significant effect on DON contamination of wheat grain, subsequent reductions in DON contamination were inconsistent when using Soil cultivation and Fertiliser, Unfortunately, under field conditions, the biological control achieved has been shown to be variable and in some tests has failed to give any control, The use of fungicides, however, have not been consistently effective in controlling FHB and in reducing DON formation, transgene-silencing at different generations is a problem to use transgenes, Information on location of QTL for FHB resistance should improve dramatically in the near future on resistance to control Fusarium head blight (FHB). Therefore, it is pressing to improve control methods, especially to DON. 展开更多
关键词 赤霉病 预防措施 植物 小麦
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Push vs pull method for endoscopic ultrasound-guided fine needle aspiration of pancreatic head lesions: Propensity score matching analysis
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作者 Mitsuru Sugimoto Tadayuki Takagi +13 位作者 Rei Suzuki Naoki Konno Hiroyuki Asama Yuki Sato Hiroki Irie Ko Watanabe Jun Nakamura Hitomi Kikuchi Yuichi Waragai Mika Takasumi Minami Hashimoto Yuko Hashimoto Takuto Hikichi Hiromasa Ohira 《World Journal of Gastroenterology》 SCIE CAS 2018年第27期3006-3012,共7页
AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic... AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic cancer patients had their first EUS-FNA between February 2001 and December 2017. Among them, 201 who underwent EUS-FNA for pancreatic head lesions were included in this study. EUS-FNA was performed by the push method in 85 patients, the pull method in 101 patients and both the push and pull methods in 15 patients. After propensity score matching(age, sex, tumor diameter, and FNA needle), 85 patients each were stratified into the push and pull groups. Patient characteristics and EUSFNA-related factors were compared between the two groups.RESULTS Patient characteristics were not significantly different between the two groups. The distance to lesion was significantly longer in the push group than in the pull group(13.9 ± 4.9 mm vs 7.0 ± 4.9 mm, P < 0.01). The push method was a significant factor influencing the distance to lesion(≥ median 10 mm)(P < 0.01). Additionally, tumor diameter ≥ 25 mm(OR = 1.91, 95%CI: 1.02-3.58, P = 0.043) and the push method(OR = 1.91, 95%CI: 1.03-3.55, P = 0.04) were significant factors contributing to the histological diagnosis of malignancy.CONCLUSION The pull method shortened the distance between the endoscope and the lesion and facilitated EUS-FNA of pancreatic head cancer. The push method contributed to the histological diagnosis of pancreatic head cancer using EUS-FNA specimens. 展开更多
关键词 Endoscopic ULTRASOUND-GUIDED fine needle ASPIRATION PANCREATIC head PANCREATIC cancer PUSH method PULL method
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Finite Element Method Computations of the Acoustics of the Human Head Based on the Projection Based Interpolation Data
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作者 Marcin Sieniek Piotr Gurgul Maciej Paszyński 《Journal of Applied Mathematics and Physics》 2014年第12期1047-1052,共6页
In this paper we present the Projection Based Interpolation (PBI) technique for construction of continuous approximation of MRI scan data of the human head. We utilize the result of the PBI algorithm to perform three ... In this paper we present the Projection Based Interpolation (PBI) technique for construction of continuous approximation of MRI scan data of the human head. We utilize the result of the PBI algorithm to perform three dimensional (3D) Finite Element Method (FEM) simulations of the acoustics of the human head. The computational problem is a multi-physics problem modeled as acoustics coupled with linear elasticity. The computational grid contains tetrahedral finite elements with the number of equations and polynomial orders of approximation varying locally on finite element edges, faces, and interiors. We utilize our own out-of-core parallel direct solver for the solution of this multi-physics problem. The solver minimizes the memory usage by dumping out all local systems from all nodes of the entire elimination tree during the elimination phase. 展开更多
关键词 FINITE Element method PROJECTION BASED INTERPOLATION ACOUSTICS of the Human head
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Experimental study of“Tong Xia”purgative method in ameliorating lung injury in acute necrotizing pancreatitis 被引量:31
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作者 Xia Q Jiang JM +3 位作者 Gong X Chen GY Li L Huang ZW 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第1期115-118,共4页
AIM To investigate the role of tumor necrosisfactor(TNF)in lung injury during acutenecrotizing pancreatitis(ANP),and thetherapeutic effect of'Tong Xia'purgativemethod in minimizing the severity of lung injury.... AIM To investigate the role of tumor necrosisfactor(TNF)in lung injury during acutenecrotizing pancreatitis(ANP),and thetherapeutic effect of'Tong Xia'purgativemethod in minimizing the severity of lung injury.METHODS Fourteen canines were randomlydivided into 3 groups:the'Tong Xia'treatmentgroup(n = 5)using Dachengqitang;salinecontrol group(n = 5),and the sham operationgroup(n = 4).TNF activity in serum and inbronchoalveolar lavage fluid(BALF),the serumendotoxin levels were measured,and theseverity of lung injury evaluated.RESULTS Elevation of TNF activity was moreprominent in BALF than in serum.TNF activity inserum at 6 and 12 hours and in BALI:wassignificantly decreased in the'Tong Xia'treatment group than in the saline control one(q=21.11,q=12.07,q=9.03,respectively,P【0.01)and the lung injury was significantlyalleviated at 12 hours as compared with that inthe saline group,manifested as amelioration otthe lung wet/ dry weight ratio,decrease inprotein concentration and neutrophils count inBALF,and improvement of pulmonaryinflammatory changes.A positive correlationwas demonstrated between serum TNF activity and endotoxin level.CONCLUSION Hypersecretion of TNF is shownto be one of the major causes of lung injuryduring ANP;'Tong Xia'purgative method couldalleviate the degree of lung injury mediated byTNF. 展开更多
关键词 Subject headings pancreatitis/therapy LUNG disease tumor NECROSIS factor Tong XIA method
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中国人标准头模BHead210的头相关传递函数数值计算 被引量:2
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作者 唐玲 付中华 《声学技术》 CSCD 2014年第3期237-242,共6页
针对基于中国人平均头部尺寸的BHead210标准头模,通过结构光扫描获取三维数据并利用边界元方法计算其头相关传递函数。将刚球模型的计算结果与解析结果进行对比,验证了计算方法的正确性,并将BHead210的计算结果与测量结果对比以观察误... 针对基于中国人平均头部尺寸的BHead210标准头模,通过结构光扫描获取三维数据并利用边界元方法计算其头相关传递函数。将刚球模型的计算结果与解析结果进行对比,验证了计算方法的正确性,并将BHead210的计算结果与测量结果对比以观察误差。给出了由边界元计算数据导出的BHead210双耳时间差、双耳声级差曲线与不同声源距离某方位的头相关传递函数幅度谱。最后对比和分析了BHead210头模数据与CIPIC公布的KEMAR头模数据的差异。 展开更多
关键词 头相关传递函数 中国人标准头模Bhead210数值计算
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Pull Breech out versus Push Impacted Head up in Emergency Cesarean Section: A Comparative Study 被引量:2
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作者 Hend S. Saleh Gamal A. Kassem +2 位作者 Mohamed El Said Mohamed Moustafa A. Ibrahiem Manal M. El Behery 《Open Journal of Obstetrics and Gynecology》 2014年第6期260-265,共6页
Objective: To compare maternal and fetal outcome associated with two methods Reverse breech extraction versus Head pushing to deliver the impacted fetal head in advanced labor requiring emergency Cesarean section. Met... Objective: To compare maternal and fetal outcome associated with two methods Reverse breech extraction versus Head pushing to deliver the impacted fetal head in advanced labor requiring emergency Cesarean section. Method: A prospective comparative study was conducted on 80 pregnant women at term with cephalic presentation in advanced labour, requiring emergency Cesarean Section. Reverse breech extraction technique (pull method) was used in 40 cases (group I) and pushing the head up through the vagina (“push” method) was tried in (group II) 40 cases. The maternal outcome was assessed by extension of the uterine Incision, bladder injury, intra and postoperative blood transfusion, Postpartum hemorrhage, wound infection and duration of hospital stay. Fetal outcome was Apgar score and admission to neonatal intensive care unit. Results: Extension of the uterine incision was significantly lower in women undergoing reverse breech extraction compared to cephalic delivery (20% versus 50%;p = 0.001). The mean operative time (pull group) was lower than that in the (push group) 59.7 ± 4.2, versus 75.2 ± 6.1 p = 0.001 and blood loss was significantly lower in the (pull group) than that in the (push group) 878 ± 67 ml, versus 1321 ± 57 ml, p = 0.001. No significant difference between groups regarding maternal and neonatal outcome. Conclusion: Reverse breech extraction (pull) is safer than pushing head up through vagina (push) for delivery of a deeply impacted fetal head in advanced labour sensitizing emergency Cesarean Section and is associated with the least maternal complications. 展开更多
关键词 Deeply Engaged head OBSTRUCTED Labor CESAREAN Section Reverse BREECH Extraction head PUSH method
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Production technique of vermicular graphite iron cylinder head of vehicle diesel engine 被引量:1
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作者 Zhou Gen Liu Wanhua 《China Foundry》 SCIE CAS 2008年第3期153-161,共9页
The 25 years' production and application have proved that vermicular graphite iron cylinder heads with vermicularity ≥50% satisfy the machinability and performance demand of diesel engine. The method, in which using... The 25 years' production and application have proved that vermicular graphite iron cylinder heads with vermicularity ≥50% satisfy the machinability and performance demand of diesel engine. The method, in which using cupola-induction furnace duplex melting and pour-over process with rare earth-ferrosilicon or rare earthsilicon compound as vermJcularizing alloy plus rare earth-magnesium-ferrosilicon as stirring alloy, is an optimal vermicularizing process for obtaining satisfied vermicularity. Using top kiss risers, enlarging kissing areas and expanding covering width and making ingates to freeze earlier are the effective measures to eliminate shrinkage, blowhole and oxide inclusions in the vermicular graphite iron cylinder heads. 展开更多
关键词 vermicular cast iron cylinder head melting and treatina process: castina method
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OBSERVATION ON THERAPEUTIC EFFECT OF ELECTROACUPUNCTURE HEAD PONINT-THROUGH-POINT BY PENETRATING TWO POINT ON ISCHEIC STROKE
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作者 肖晓华 李瑞春 +3 位作者 朱红霞 帅记炎 徐明芳 傅缨 《World Journal of Acupuncture-Moxibustion》 2008年第3期15-22,共8页
Objective To probe methods and therapeutic effects of Head Acupuncture on ischemic stroke. Methods One hundred and twelve cases were randomly divided into observation group (head acupuncture group) and control group (... Objective To probe methods and therapeutic effects of Head Acupuncture on ischemic stroke. Methods One hundred and twelve cases were randomly divided into observation group (head acupuncture group) and control group (body acupuncture group). After treatment of 28 days, changes of linguistic function and paralysis level of limbs before and after treatment were investigated. Results The total effective rate was 96.6% in the observation group and 90.7%, in the control group, with a significant difference between the two groups (P<0.05). Conclusion The electroacupuncture head point-through-point by penetrating two point therapy is one of effective methods for ischemic stroke. 展开更多
关键词 Ischemic Stroke/acupuncture head Acupuncture Point-Through-Point method Electroacupuncture
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ON HEAD-ON COLLISION BETWEEN TWO GKDV SOLITARY WAVES IN A STRATIFIED FLUID 被引量:1
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作者 朱勇 戴世强 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1991年第4期300-308,共9页
In this paper,using the reductive perturbation method combined with the PLK method and two-parameter expansions,we treat the problem of head-on collision between two solitary waves described by the generalized Kortewe... In this paper,using the reductive perturbation method combined with the PLK method and two-parameter expansions,we treat the problem of head-on collision between two solitary waves described by the generalized Korteweg-de Vries equation (the gKdV equation) and obtain its second-order approximate solution.The results show that after the collision,the gKdV solitary waves preserve their profiles and during the collision,the maximum amplitute is the linear superposition of two maximum amplitudes of the impinging solitary waves. 展开更多
关键词 gKdV solitary wave head-on collision reductive perturbation method PLK method
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Finite Difference Method of Modelling Groundwater Flow
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作者 Magnus.U. Igboekwe N. J. Achi 《Journal of Water Resource and Protection》 2011年第3期192-198,共7页
In this study, finite difference method is used to solve the equations that govern groundwater flow to obtain flow rates, flow direction and hydraulic heads through an aquifer. The aim therefore is to discuss the prin... In this study, finite difference method is used to solve the equations that govern groundwater flow to obtain flow rates, flow direction and hydraulic heads through an aquifer. The aim therefore is to discuss the principles of Finite Difference Method and its applications in groundwater modelling. To achieve this, a rectangular grid is overlain an aquifer in order to obtain an exact solution. Initial and boundary conditions are then determined. By discretizing the system into grids and cells that are small compared to the entire aquifer, exact solutions are obtained. A flow chart of the computational algorithm for particle tracking is also developed. Results show that under a steady-state flow with no recharge, pathlines coincide with streamlines. It is also found that the accuracy of the numerical solution by Finite Difference Method is largely dependent on initial particle distribution and number of particles assigned to a cell. It is therefore concluded that Finite Difference Method can be used to predict the future direction of flow and particle location within a simulation domain. 展开更多
关键词 Finite DIFFERENCE method GROUNDWATER MODELLING Particle Tracking Algorithm DISCRETIZATION Flow Rates HYDRAULIC headS
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Preliminary Study on the Histology in the Head Sarcoma of Goldfish (Carassius auratus)
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作者 Lei Wang Zaizhong Chen +6 位作者 Caixia Hu Feng Yan Jun Xu Xuehua Wang Yuanyuan Zhou Wei Wang Weihua Zhao 《Open Journal of Animal Sciences》 2015年第1期44-49,共6页
The sarcoma structure of goldfish was first analyzed by frozen section technique. The present study revealed the alkaline and acid phosphatase distribution in the head sarcoma of goldfish. And the histochemical staini... The sarcoma structure of goldfish was first analyzed by frozen section technique. The present study revealed the alkaline and acid phosphatase distribution in the head sarcoma of goldfish. And the histochemical staining in situ by calcium-cobalt method and lead nitrate method displayed a large amount of alkaline and acid phosphatases in the head sarcoma, with higher enzyme activity. The alkaline and acid phosphatases belong to hydrolases, which are widely present in various tissues. The results showed that the activity of external sarcoma is similar to the middle one, while there was more alkaline phosphatase near to the tissue sarcoma under the goldfish scales. And they have the strong activity. The study will lay the theoretical basis on enhancing the ornamental value of goldfish. 展开更多
关键词 GOLDFISH head SARCOMA Frozen Sectioning method AKP ACP
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Modeling of the Absorption of the Electromagnetic Wave Energy in the Human Head Induced by Cell Phone
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作者 Damian Goik Marcin Sieniek +1 位作者 Piotr Gurgul Maciej Paszyński 《Journal of Applied Mathematics and Physics》 2014年第12期1079-1084,共6页
In this paper, we present the Projection Based Interpolation (PBI) technique for construction of continuous approximation of MRI scan data of the human head. We utilize the result of the PBI algorithm to perform three... In this paper, we present the Projection Based Interpolation (PBI) technique for construction of continuous approximation of MRI scan data of the human head. We utilize the result of the PBI algorithm to perform three-dimensional (3D) Finite Element Method (FEM) simulations of the heating of the human head induced by cell phone. In particular, we utilize the Pennes equation to describe the bioheat transfer with the right hand side representing the heat generated by cell phone. We utilize our own non-stationary time dependent multi-thread parallel direct solver for the solution of this computational problem. From our numerical results it follows that 15 minutes (1000 seconds) exposure to the cell phone radiation implies up to 2 degrees Celsius increase of the temperature of the brain in the range close to the cell phone. 展开更多
关键词 FINITE Element method PROJECTION Based INTERPOLATION Pennes Equation HEATING of the Human head
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Advances in needle-knife for the treatment of early and middle stage Osteonecrosis of the Femoral Head
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作者 Yan Yan Hai-Jun He 《Journal of Hainan Medical University》 2020年第1期63-67,共5页
Osteonecrosis of the Femoral Head (ONFH) is a refractory disease of orthopedics, and its incidence is gradually increasing. Often due to lack of timely intervention, the femoral head collapses, eventually causing hip ... Osteonecrosis of the Femoral Head (ONFH) is a refractory disease of orthopedics, and its incidence is gradually increasing. Often due to lack of timely intervention, the femoral head collapses, eventually causing hip pain and difficulty in activities. At present, the treatment of hip preservation after the collapse of osteonecrosis of the femoral head has received everyone's attention, but many hip-preserving measures are controversial in terms of efficacy and indications. Needle-knife therapy is a kind of hip-protection therapy with low risk, small trauma, bleeding, and less and shorter treatments. This article reviews the literatures related to needle-knife therapy for osteonecrosis of the femoral head, and summarizes the clinical treatment of osteonecrosis of the femoral head based on needle-knife, and prospects for its research. 展开更多
关键词 Needle-knife OSTEONECROSIS of the FEMORAL head Mechanism TREATMENT method Efficacy evaluation Review
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HEAD-ON COLLISION BETWEEN TWO mKdV SOLITARY WAVES IN A TWO-LAYER FLUID SYSTEM
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作者 朱勇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第5期407-417,共11页
In this paper, based on the equations presented in [2], the head-on collision between two solitary waves described by the modified KdV equation (the mKdVequation, for short) is investigated by using the reductive pert... In this paper, based on the equations presented in [2], the head-on collision between two solitary waves described by the modified KdV equation (the mKdVequation, for short) is investigated by using the reductive perturbation method combined with the PLK method. These waves propagate at the interface of a two-fluid system, in which the density ratio of the two fluids equals the square of the depth ratio of the fluids. The second order perturbation solution is obtained. It is found that in the case of disregarding the nonuniform phase shift, the solitary waves preserve their original profiles after collision, which agrees with Fornberg and Whitham's numerical result of overtaking collision[6] whereas after considering the nonuniform phase shift, the wave profiles may deform after collision. 展开更多
关键词 mKdV solitary wave head-on collision perturbation method
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Head-on collision between two hydroelastic solitary waves with Plotnikov-Toland's plate model
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作者 M.M.Bhatti D.Q.Lu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2018年第6期384-392,I0004,共10页
Head-on collision between two hydroelastic solitary waves propagating at the surface of an incompressible and ideal fluid covered by a thin ice sheet is analytically studied by means of a singular perturbation method.... Head-on collision between two hydroelastic solitary waves propagating at the surface of an incompressible and ideal fluid covered by a thin ice sheet is analytically studied by means of a singular perturbation method. The ice sheet is represented by the Plotnikov-Toland model with the help of the special Cosserat theory of hyperelastic shells and the Kirchhoff-Love plate theory,which yields the nonlinear and conservative expression for the bending forces. The shallow water assumption is taken for the fluid motion with the Boussinesq approximation. The resulting governing equations are solved asymptotically with the aid of the Poincaré-Lighthill-Kuo method,and the solutions up to the third order are explicitly presented. It is observed that solitary waves after collision do not change their shapes and amplitudes. The wave profile is symmetric before collision, and it becomes, after collision, unsymmetric and titled backward in the direction of wave propagation. The wave profile significantly reduces due to greater impacts of elastic plate and surface tension. A graphical comparison is presented with published results, and the graphical comparison between linear and nonlinear elastic plate models is also shown as a special case of our study. 展开更多
关键词 head-on collision Hydroelastic solitary waves Ice sheet PLK method
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考虑激励幅值慢变的卷绕头转子系统动力学建模 被引量:1
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作者 王东强 史卫士 +2 位作者 于贺春 董学武 姜海芹 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第3期230-239,共10页
卷绕头转子系统结构之间的耦合振动和时频变激励使振动问题十分复杂,为了更准确地研究其动力学特性,根据转子动力学理论,使用有限元方法建立了考虑多盘质量慢变的卷绕头非线性转子系统整机动力学模型,运用Newmark-β数值积分方法对其动... 卷绕头转子系统结构之间的耦合振动和时频变激励使振动问题十分复杂,为了更准确地研究其动力学特性,根据转子动力学理论,使用有限元方法建立了考虑多盘质量慢变的卷绕头非线性转子系统整机动力学模型,运用Newmark-β数值积分方法对其动力学特性求解,得到仅存在初始不平衡量以及卷装不良带来的激励频率、幅值慢变下的非线性动力学行为。通过分析轴心轨迹、时域波形和幅频特性曲线等结果,发现卷绕头转子系统对因卷装不良引起的激励幅值慢变较为敏感,出现新的频率成分。进一步对比分析了不同节点处的振动频谱,其结果可为卷绕头转子系统动力学设计和故障识别提供一定理论支持。 展开更多
关键词 卷绕头转子系统 质量慢变 时频分析 有限元模型 激励幅值慢变 动力学特性
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个性化头部生物力学模型的开发及验证
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作者 李海岩 曹祎帆 +3 位作者 贺丽娟 吕文乐 崔世海 阮世捷 《中国医学物理学杂志》 CSCD 2024年第7期883-889,共7页
本文提出了一种个性化头部生物力学模型建模方法,并对所生成模型进行了有效性验证。该方法以图斯特50th百分位头部生物力学模型为基础,基于目标模型头部CT数据,采用三维点云配准和自由网格变形法,实现具有详实脑组织结构的个性化头部生... 本文提出了一种个性化头部生物力学模型建模方法,并对所生成模型进行了有效性验证。该方法以图斯特50th百分位头部生物力学模型为基础,基于目标模型头部CT数据,采用三维点云配准和自由网格变形法,实现具有详实脑组织结构的个性化头部生物力学模型的快速建模。通过重构经典尸体试验,发现该方法构建的个性化头部生物力学模型在运动学和生物力学响应方面与尸体试验结果高度一致,且与通过逆向工程方法开发的头部生物力学模型并无明显差异,验证了本文方法所开发模型的有效性。因此,本文方法可用于快速构建具有详细解剖学结构的个性化头部生物力学模型,为损伤生物力学、临床医学和法医鉴定等领域的数字化需求提供基础计算分析工具。 展开更多
关键词 头部生物力学模型 个性化建模 自由网格变形 有限元法
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多通道光栅莫尔信号实时细分与等分平均技术研究
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作者 李强 刘宏伟 +2 位作者 何韬 杜坤 夏仰球 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第9期189-196,共8页
圆光栅受刻线误差、安装偏心等多种因素的共同影响,其定位精度无法直接满足高精度测角系统的需求。多读数头等分平均方法可以实现圆光栅精度的自校准,是提高测角系统精度的有效方法。然而,商业伺服控制系统通常不支持多路读数头信号实... 圆光栅受刻线误差、安装偏心等多种因素的共同影响,其定位精度无法直接满足高精度测角系统的需求。多读数头等分平均方法可以实现圆光栅精度的自校准,是提高测角系统精度的有效方法。然而,商业伺服控制系统通常不支持多路读数头信号实时接入同一路伺服轴,这造成了等分平均方法的在线应用存在困难。本文针对多通道光栅莫尔信号的采样、误差补偿、实时细分和等分平均进行研究,基于FPGA平台实现了多读数头实时处理系统的研制,并在测角转台开展了应用验证。设计了细分值稳定性、控制分辨率、角定位精度和细分误差实验,验证了多读数头实时处理系统的性能。所设计的多读数头处理系统,在测角转台上可以满足0.005″的控制分辨率需求,取得了0.58″定位精度和0.06″重复定位精度等测试结果。 展开更多
关键词 光栅莫尔信号 多读数头 等分平均方法 误差补偿 FPGA 转台
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耳鼻咽喉头颈外科专科护士核心能力培训方案的构建
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作者 潘乐 荆璇 +5 位作者 谭茜 刘爽 李丽红 郑婷 郑智英 皇甫辉 《护理研究》 北大核心 2024年第14期2575-2581,共7页
目的:构建耳鼻咽喉头颈外科专科护士核心能力培训方案。方法:通过文献研究、半结构式访谈构建耳鼻咽喉头颈外科专科护士核心能力培训方案初稿,采用德尔菲专家函询法进行3轮专家函询,形成耳鼻咽喉头颈外科专科护士核心能力培训方案终稿... 目的:构建耳鼻咽喉头颈外科专科护士核心能力培训方案。方法:通过文献研究、半结构式访谈构建耳鼻咽喉头颈外科专科护士核心能力培训方案初稿,采用德尔菲专家函询法进行3轮专家函询,形成耳鼻咽喉头颈外科专科护士核心能力培训方案终稿。结果:3轮专家函询问卷有效回收率分别为83.33%、91.67%和100.00%,专家权威系数为0.951,0.958和0.963,肯德尔和谐系数为0.398,0.435和0.495(均P<0.001),变异系数均<0.25。最终形成的耳鼻咽喉头颈外科专科护士核心能力培训方案的培训目标包括3项一级指标、26项二级指标,培训内容包括6项一级指标、35项二级指标,培训管理包括8项一级指标、19项二级指标,培训考核评价包括4项一级指标、12项二级指标。结论:构建的耳鼻咽喉头颈外科专科护士核心能力培训方案具有科学性、可靠性,可为完善我国耳鼻咽喉头颈外科专科护士培训提供参考。 展开更多
关键词 耳鼻咽喉头颈外科 专科护士 核心能力 培训方案 德尔菲法 半结构式访谈 护理
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