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Loose Body in the Knee Joint: A Case Report
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作者 Hussein Khudhur Joudi Habbal Waleed Mohammed 《Open Journal of Orthopedics》 2024年第10期436-440,共5页
Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;ho... Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;however, their complete eradication is often challenging and may not address underlying diseases, leading to persistent symptoms and the risk of new loose body formation. Aim: This case report aims to present the findings and surgical management of a 52-year-old male with an unusually large osseous loose body in the knee joint and associated pathologies. Case Presentation: The patient, a 52-year-old male, experienced recurrent episodes of severe, sudden, and painful locking of the knee joint, leading to difficulties moving. A plain MRI study was conducted to evaluate the condition of the knee joint, which revealed various degenerative changes and the presence of a loose body. Subsequently, an arthroscopic examination was performed under general anesthesia, uncovering the presence of an abnormally large loose body, as well as other pathologies including chondropathy, meniscal degeneration, and Baker’s cyst. Conclusion: Loose bodies (LBs) in the knee joint pose significant challenges and may lead to debilitating symptoms. Timely diagnosis and appropriate surgical intervention are crucial for symptom relief and the prevention of further joint damage as arthroscopic excision. Comprehensive imaging has a vital role in guiding treatment decisions and optimizing patient outcomes. In this case, the removal of the loose body improved patient outcomes and helped prevent potential joint complications. 展开更多
关键词 loose Bodies Knee Joint ARTHROSCOPY MRI Osseous loose Body Surgical Management Meniscal Degeneration Baker’s Cyst BURSITIS Osteoarthritic Changes Comprehensive Treatment
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Stability analysis of loose accumulation slopes under rainfall:case study of a high‑speed railway in Southwest China
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作者 Xin Wang Qian Su +2 位作者 Zongyu Zhang Feihu Huang Chenfang He 《Railway Engineering Science》 EI 2024年第1期95-106,共12页
The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce... The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce adverse geological disasters under rainfall conditions.To ensure the smooth construction of the high-speed railway and the subsequent safe operation,it is necessary to master the stability evolution process of the loose accumulation slope under rainfall.This article simulates rainfall using the finite element analysis software’s hydromechanical coupling module.The slope stability under various rainfall situations is calculated and analysed based on the strength reduction method.To validate the simulation results,a field monitoring system is established to study the deformation characteristics of the slope under rainfall.The results show that rainfall duration is the key factor affecting slope stability.Given a constant amount of rainfall,the stability of the slope decreases with increasing duration of rainfall.Moreover,when the amount and duration of rainfall are constant,continuous rainfall has a greater impact on slope stability than intermittent rainfall.The setting of the field retaining structures has a significant role in improving slope stability.The field monitoring data show that the slope is in the initial deformation stage and has good stability,which verifies the rationality of the numerical simulation method.The research results can provide some references for understanding the influence of rainfall on the stability of loose accumulation slopes along high-speed railways and establishing a monitoring system. 展开更多
关键词 High-speed railway loose accumulation slope Slope stability analysis Rainfall effect Strength reduction
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Optimization of Inducing Conditions for Loose Callus of Pinellia ternata 被引量:3
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作者 朱艳芳 毛春娜 +3 位作者 张爱民 薛建平 李佳娣 宋运贤 《Agricultural Science & Technology》 CAS 2011年第8期1116-1117,1124,共3页
[Objective] The research aimed to establish the cell suspension culture system of Pinellia ternate.[Method] The petiole of Pinellia ternate was as the explant.The orthogonal test was used to study the influences of fo... [Objective] The research aimed to establish the cell suspension culture system of Pinellia ternate.[Method] The petiole of Pinellia ternate was as the explant.The orthogonal test was used to study the influences of four plant growth substances(2,4-D,NAA,picloram and KT)and their mixture ratios on the formation of loose callus.[Result] The induction effect of 2,4-D and picloram on the petiole callus of Pinellia ternate was the most significant.Then,the second ones were KT and NAA.The optimal medium which induced Pinellia ternate petiole to form the loose callus was MS+0.5 mg/L of 2,4-D+1.0 mg/L of NAA+1.0 mg/L of picloram+1.5 mg/L of KT.[Conclusion] The research laid the foundation for extracting the active ingredient from the cell suspension of Pinellia ternate and producing the artificial seed. 展开更多
关键词 Pinellia ternata PETIOLE loose callus Suspension culture
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Strength performance of mortise and loose-tenon furniture joints under uniaxial bending moment 被引量:6
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作者 Mohammad Derikvand Ghanbar Ebrahimi 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期483-486,共4页
We determined the effects of adhesive type and loose tenon dimensions (length and thickness) on bending strength of T-shaped mor- tise and loose-tenon joints. Polyvinyl acetate (PVAc) and two-component polyuretha... We determined the effects of adhesive type and loose tenon dimensions (length and thickness) on bending strength of T-shaped mor- tise and loose-tenon joints. Polyvinyl acetate (PVAc) and two-component polyurethane (PU) adhesives were used to construct joint specimens. The bending moment capacity of joints increased significantly with increased length and thickness of the loose tenon. Bending moment capacity of joints constructed with PU adhesive was approximately 13% higher than for joints constructed with PVAc adhesive. We developed a predictive equation as a function of adhesive type and loose tenon dimensions to estimate the strength of the joints constructed of oriental beech (Fagus orientalis L.) under uniaxial bending load. 展开更多
关键词 bending moment capacity mortise and loose tenon loose tenon dimensions polyvinyl acetate two-component polyurethane
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基于Loose r-sample的网格质量保持技术 被引量:1
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作者 周喆 吕思哲 顾力栩 《计算机工程》 CAS CSCD 2012年第16期219-222,共4页
为保证虚拟手术系统中的网格质量,提出一种基于Loose r sample理论的快速表面网格重建算法。记录满足Loose r sample采样定理的点集,用以描述物体的轮廓。通过约束Delaunay方法对该点集进行三角化,标记顶点和Delaunay单元,重构新的网格... 为保证虚拟手术系统中的网格质量,提出一种基于Loose r sample理论的快速表面网格重建算法。记录满足Loose r sample采样定理的点集,用以描述物体的轮廓。通过约束Delaunay方法对该点集进行三角化,标记顶点和Delaunay单元,重构新的网格。实验结果表明,该算法能够保证生成网格的质量,简化仿真复杂度。 展开更多
关键词 网格质量 虚拟手术系统 loose rsample理论 DELAUNAY三角剖分 VORONOI图 局部特征
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Present Situation and Prospect of Professional Grading and Loose-leaf Purchasing of Flue-cured Tobacco 被引量:1
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作者 袁胜国 李光雷 +1 位作者 张灿洪 冯景飞 《Agricultural Science & Technology》 CAS 2014年第4期538-541,556,共5页
In terms of the common practice of professional grading and loose-leaf purchasing technology, the advantages of these technologies were demonstrated. The problems and proposals of the professional grading leaves purch... In terms of the common practice of professional grading and loose-leaf purchasing technology, the advantages of these technologies were demonstrated. The problems and proposals of the professional grading leaves purchasing model were also summarized and analyzed, so as to provide practical experiences for fur- ther promotion of loose-leaf purchasing. 展开更多
关键词 Flue-cured tobacco loose leaf GRADING PURCHASING
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Department of Civil Engineering, Universitas Katolik Parahyangan, Bandung, 40141, Indonesiaof loose sand with fungus 被引量:6
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作者 Aswin Lim Petra Cahaya Atmaja Siska Rustiani 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第1期180-187,共8页
This article presents an innovative method of bio-mediated soil improvement for increasing the shear strength of loose sand.The improvement is realized by mixing the loose sand with the inoculum of Rhizopus oligosporu... This article presents an innovative method of bio-mediated soil improvement for increasing the shear strength of loose sand.The improvement is realized by mixing the loose sand with the inoculum of Rhizopus oligosporus,a kind of fungus widely used in food industry for making Indonesian tempeh.The objective of this article is to investigate the performance and mechanism of mixing tempeh inoculum as a binding agent of loose sand particles.The inoculum dosage,water content of loose sand,and curing time were examined for identifying the increment of unconfined compressive strength(q_u)of the samples.The results showed that q_u of the treated samples increased when the inoculum dosage was elevated.It shows that 5.24%inoculum could yield 68 kPa of q_u,and 5%water content and 3 d curing time produced the maximum q_u.Moreover,the mechanism of hypha and mycelium in binding the soil particles was clearly observed using a digital microscope and scanning electron microscope. 展开更多
关键词 Bio-mediated soil improvement loose SAND RHIZOPUS oligosporus
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Prediction of oxygen concentration and temperature distribution in loose coal based on BP neural network 被引量:9
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作者 ZHANG Yong-jian WU Guo-guang XU Hong-feng MENG Xian-liang WANG Guang-you 《Mining Science and Technology》 EI CAS 2009年第2期216-219,共4页
An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures ... An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures within coal stockpiles, it is vital to obtain information of self-heating conditions and tendencies of spontaneous coal combustion. For laboratory conditions, we designed our own experimental equipment composed of a control-heating system, a coal column and an oxygen concentration and temperature monitoring system, for simulation of spontaneous combustion of block coal (13-25 mm) covered with fine coal (0-3 mm). A BP artificial neural network (ANN) with 150 training samples was gradually established over the course of our experiment. Heating time, relative position of measuring points, the ratio of fine coal thickness, artificial density, voidage and activation energy were selected as input variables and oxygen concentration and temperature of coal column as output variables. Then our trained network was applied to predict the trend on the untried experimental data. The results show that the oxygen concentration in the coal column could be reduced below the minimum still able to induce spontaneous combustion of coal - 6% by covering the coal pile with fine coal, which would meet the requirement to prevent spontaneous combustion of coal stockpiles. Based on the prediction of this ANN, the average errors of oxygen concentration and temperature were respectively 0.5% and 7 ℃, which meet actual tolerances. The implementation of the method would provide a practical guide in understanding the course of self-heating and spontaneous combustion of coal stockpiles. 展开更多
关键词 loose coal neural netwOrk spontaneous combustion of coal oxygen concentration TEMPERATURE PREDICTION
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Effects of loose deposits on debris flow processes in the Aizi Valley, southwest China 被引量:7
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作者 LIU Mei ZHANG Yong +3 位作者 TIAN Shu-feng CHEN Ning-sheng MAHFUZR Rahman JAVED Iqba 《Journal of Mountain Science》 SCIE CSCD 2020年第1期156-172,共17页
Loose deposits, rainfall and topography are three key factors that triggering debris flows.However, few studies have investigated the effects of loose deposits on the whole debris flow process.On June 28, 2012, a cata... Loose deposits, rainfall and topography are three key factors that triggering debris flows.However, few studies have investigated the effects of loose deposits on the whole debris flow process.On June 28, 2012, a catastrophic debris flow occurred in the Aizi Valley, resulting in 40 deaths.The Aizi Valley is located in the Lower Jinsha River,southwestern Sichuan Province, China. The Aizi Valley debris flow has been selected as a case for addressing loose deposits effects on the whole debris flow process through remote sensing, field investigation and field experiments. Remote sensing interpretation and laboratory experiments were used to obtain the distribution and characteristics of the loose deposits, respectively. A field experiment was conducted to explore the mechanics of slope debris flows, and another field investigation was conducted to obtain the processes of debris flow formation, movement and amplification. The results showed that loose deposits preparation, slope debris flow initiation,gully debris flow confluence and valley debris flow amplification were dominated by the loose deposits.Antecedent droughts and earthquake activities may have increased the potential for loose soil sources in the Aizi Valley, which laid the foundation for debris flow formation. Slope debris flow initiated under rainfall, and the increase in the water content as well as the pore water pressure of the loose deposits were the key factors affecting slope failure. The nine gully debris flows converged in the valley, and the peak discharge was amplified 3.3 times due to a blockage and outburst caused by a large boulder. The results may help in predicting and assessing regional debris flows in dry-hot and seismic-prone areas based on loose deposits, especially considering large boulders. 展开更多
关键词 Aizi Valley loose deposits Debris flow process Slope debris flow Boulder blockage Discharge amplification
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Dynamics of loose granular flow and its subsequent deposition in a narrow mountainous river 被引量:3
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作者 LEI Ming XU Ze-xing +1 位作者 ZHAO Tao WANG Xie-kang 《Journal of Mountain Science》 SCIE CSCD 2019年第6期1367-1380,共14页
A large amount of loose debris materials were deposited on the slope of mountainous areas after the 2008 Ms 8.0 Wenchuan earthquake. During and after the earthquake, these loose debris deposits collapsed and slide int... A large amount of loose debris materials were deposited on the slope of mountainous areas after the 2008 Ms 8.0 Wenchuan earthquake. During and after the earthquake, these loose debris deposits collapsed and slide into valleys or rivers, changing river sediment supply condition and channel morphology. To investigate the mechanisms of granular flow and deposition, the dynamics of slope failure and sediment transportation in typical mountainous rivers of different intersection angles were analyzed with a coupling model of Computational Fluid Dynamics and Discrete Element Method(CFD-DEM). The numerical results show that the change of intersection angle between the granular flow flume and the river channel can affect the deposit geometry and the fluid flow field significantly. As the intersection angle increases, the granular velocity perpendicular to the river channel increases, while the granular velocity parallel to the river channel decreases gradually. Compared to the test of dry granular flow, the CFD-DEM coupling tests show much higher granular velocity and larger volume of sediments entrained in the river. Due to the river flow, particles located at the edge of the deposition will move downstream gradually and the main section of sediments deposition moves from the center to the edge of the river channel. As a result, sediment supply in the downstream river will distribute unevenly. Under the erosion of fluid flow, the proportion of fine particles increases, while the proportion of coarse particles decreases gradually in the sediment deposition. The build-up of accumulated sediment mass will cause a significant increase in water level in the river channel, thus creating serious flooding hazard in mountainous rivers. 展开更多
关键词 loose DEBRIS materials SEDIMENT supply CFD-DEM coupling method NUMERICAL simulations
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Finite element analysis of stress and strain distributions in mortise and loose tenon furniture joints 被引量:6
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作者 Mohammad Derikvand Ghanbar Ebrahimi 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期677-681,共5页
We studied the effect of loose tenon dimensions on stress and strain distributions in T-shaped mortise and loose tenon (M&amp;LT) furni-ture joints under uniaxial bending loads, and determined the effects of loose ... We studied the effect of loose tenon dimensions on stress and strain distributions in T-shaped mortise and loose tenon (M&amp;LT) furni-ture joints under uniaxial bending loads, and determined the effects of loose tenon length (30, 45, 60, and 90 mm) and loose tenon thickness (6 and 8 mm) on bending moment capacity of M&amp;LT joints constructed with polyvinyl acetate (PVAc) adhesive. Stress and strain distributions in joint elements were then estimated for each joint using ANSYS finite element (FE) software. The bending moment capacity of joints increased significantly with thickness and length of the tenon. Based on the FE analysis results, under uniaxial bending, the highest shear stress values were obtained in the middle parts of the tenon, while the highest shear elastic strain values were estimated in glue lines between the tenon sur-faces and walls of the mortise. Shear stress and shear elastic strain values in joint elements generally increased with tenon dimensions and corre-sponding bending moment capacities. There was consistency between predicted maximum shear stress values and failure modes of the joints. 展开更多
关键词 bending moment capacity failure mode finite element furniture mortise and loose tenon joint stress and strain distributions
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Delayed presentation of a loose body in undisplaced paediatric talar neck fracture 被引量:2
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作者 Vishal Patel Benjamin Bloch +1 位作者 Nicholas Johnson Jitendra Mangwani 《World Journal of Orthopedics》 2014年第3期398-401,共4页
Fractures of the talus are rare in children.A high index of suspicion is needed to avoid missing such an injury,which is not an uncommon occurrence especially with undisplaced fractures.We present an unusual case of a... Fractures of the talus are rare in children.A high index of suspicion is needed to avoid missing such an injury,which is not an uncommon occurrence especially with undisplaced fractures.We present an unusual case of an undisplaced talar neck fracture in a five-year-old child leading to a delayed presentation of a symptomatic osteochondral loose body in the ankle joint.To our knowledge there are no reports in the literature of osteochondral loose bodies occurring in conjunction with an associated undisplaced talar neck fracture in either children or adults.The loose body was removed using anterior ankle arthroscopy.The child had an uneventful post operative recovery and regained full range of movement and function of his ankle joint and was discharged at one year follow-up.We aim to highlight the need to have a low threshold to further evaluate symptomatic children after fracture healing of an undisplaced talar neck fracture for a possible associated loose bodyin the ankle joint. 展开更多
关键词 TALUS Fracture loose BODY ANKLE ARTHROSCOPY Children
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Superposition model for analyzing the dynamic ground subsidence in mining area of thick loose layer 被引量:2
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作者 Defeng Hou Dehai Li +1 位作者 Guosheng Xu Yanbin Zhang 《International Journal of Mining Science and Technology》 EI CSCD 2018年第4期656-661,共6页
The dynamic ground subsidence due to underground mining is a complicated time-dependent and rate- dependent process. Based. on the theory of rock rheology and probability integral method, this study developed the supe... The dynamic ground subsidence due to underground mining is a complicated time-dependent and rate- dependent process. Based. on the theory of rock rheology and probability integral method, this study developed the superposltlOn model for the prediction and analysis of the ground dynamic subsidence in mining area of thick !oose layer. The model consists of two parts (the prediction of overlying bedrock and the prediction of thick loose layer). The overlying bedrock is regarded as visco-elastic beam, of which the dynamic subsidence is predicted by the Kelvin visco-elastic rheological model. The thick loose layer is regarded as random medium, and the ground dynamic subsidence, is predicted by the probability integral model. At last, the two prediction models are vertically stacked in the same coordinate system, and the bedrock dynamic subsidence is regarded as a variable mining thickness input into the prediction model of ground dynamic subsidence. The prediction results obtained were compared w^th actual movement and deformation data from Zhao I and Zhao II mine, central China. The agreement of the prediction results with the. field measurements.show that the superposition model (SM) is more satisfactory and the formulae obtained are more effective than the classical single probability Integral model(SPIM), and thus can be effectively used for predicting the ground dynamic subsidence in mining area of thick loose layer. 展开更多
关键词 Thick loose layer Dynamic groundsubsidence Kelvin visco-elastic rheological model Random medium Single probability integral model Superposition model
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Fractal analysis of thermal conduction of loose coal 被引量:2
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作者 WANG Yijiang ZHOU Guoqing +1 位作者 WEI Yazhi ZHOU Yang 《Mining Science and Technology》 EI CAS 2010年第6期831-834,838,共5页
For deep mining engineering, heat transfer of coal mass is a vital factor in the thermal environment of coal mines. In order to study the thermal conduction mechanism, we obtained gray images of coal mass microstructu... For deep mining engineering, heat transfer of coal mass is a vital factor in the thermal environment of coal mines. In order to study the thermal conduction mechanism, we obtained gray images of coal mass microstructure by scanning samples with a digital microscope. With the use of Matlab, these gray images were transformed into binary images, which were then transformed into a corresponding matrix consisting only of the values 0 and 1. According to the calculation method of box-counting dimension, we calculated the fractal dimension of the loose coal to be approximately 1.86. The thermal conductivity expressions of loose coal were derived based on the simulation method of thermal resistance. We calculated the thermal conductivity of loose coal by using a fractal model and compared the calculated values with our experimental data. The results show that the test data show an encourag-ing agreement with the calculated values. Hence fractal theory is a feasible method for studying thermal conductivity of loose coal. 展开更多
关键词 loose coal thermal conductivity fractal theory box-counting dimension
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SIMUUTION OF ELECTROMAGNETIC TUBE BULGING BASED ON LOOSE COUPLING METHOD 被引量:6
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作者 LI Zhong LI Chunfeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期566-569,共4页
A loose coupling method is used to solve the electromagnetic tube bulging. ANSYS/ EMAG is used to model the time varying electromagnetic field with the discharge current used as excitation, in order to obtain the radi... A loose coupling method is used to solve the electromagnetic tube bulging. ANSYS/ EMAG is used to model the time varying electromagnetic field with the discharge current used as excitation, in order to obtain the radial and axial magnetic pressure acting on the tube, the magnetic pressure is then used as boundary conditions to model the high velocity deformation of tube with DYNAFORM, The radial magnetic pressure on the tube decreases from the center to the tube end, axial magnetic pressure is greater near the location equal to the coil height and slight in the other region. The radial displacement of deformed workpicces is distributed uniformly near the tube center and decreases from the center to the end; Deformation from the location equal to coil height to the tube end is little. This distribution is consistent with the distribution of radial pressure; Effect of the axial magnetic pressure on deformation can be ignored, The calculated results show well agreements with the experimental results. 展开更多
关键词 loose coupling method Electromagnetic tube bulging Excitation Magnetic pressure
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Problems and Countermeasures of Acquisition of Professionally-graded Flue-cured Tobacco Loose Leaf 被引量:2
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作者 张明发 《Agricultural Science & Technology》 CAS 2013年第8期1122-1124,共3页
Based on existing problems of loose leaf acquisition,some measures can be taken,including improvement of acquisition infrastructure,innovation of acquisition and management models,reinforcement of professional service... Based on existing problems of loose leaf acquisition,some measures can be taken,including improvement of acquisition infrastructure,innovation of acquisition and management models,reinforcement of professional services and training,high-lighting grading management,which would not only reduce farmers' efforts,but also lower storage pressure,as well as improving grading quality of tobacco leaf. 展开更多
关键词 Flue-cured tobacco Acquisition of loose leaf Professionally-graded COUNTERMEASURES
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Estimation of Loose Status of Jigging Bed Based on Adaptive Neuro-Fuzzy Inference System 被引量:2
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作者 CHENG Jian GUO Yi-nan QIAN Jian-sheng 《Journal of China University of Mining and Technology》 EI 2006年第3期270-273,共4页
In the separation process with a jig washer, an accurate on-line measurement of loose status of a jigging bed is essential for a successful control of coal quality and loose status is difficult to measure on-line dire... In the separation process with a jig washer, an accurate on-line measurement of loose status of a jigging bed is essential for a successful control of coal quality and loose status is difficult to measure on-line directly in industrial process situations. So a soft-sensor technology is needed for this purpose. The soft-sensor model is developed in the experiment by an adaptive neuro-fuzzy inference system (ANFIS) which has a remarkable ability of learning and generalization. Based on the analysis of the technologic mechanism of jigging bed, the structure of the ANFIS is established to build the soft-sensor model of loose status estimation. The ANFIS is trained by a hybrid learning algorithm. Finally, the simulation results and comparison analysis are presented, which indicate that the ANFIS has better abilities of learning and generalization than the RBF and the BP networks. Thus, it is possible that the loose status of the jigging bed can be estimated on-line bv using ANFIS. 展开更多
关键词 soft-sensor ANFIS loose status jigging bed
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Ground Subsidence in Areas of Loose Porous Aquifers 被引量:1
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作者 LIYixiang GAOGuanhua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期829-837,共9页
Groundwater is one of the important water resources in northern China's plain areas. Many severe geological hazards have occurred in these areas due to ground subsidence which is caused by over exploitation of gro... Groundwater is one of the important water resources in northern China's plain areas. Many severe geological hazards have occurred in these areas due to ground subsidence which is caused by over exploitation of groundwater. This paper introduces and analyses the ground subsidence caused by groundwater exploitation and its mechanism in the northern China's plains. A ground subsidence prediction model has been developed based on the consolidation theory. The authors have tested this model in a case study of Fuyang City, Anhui Province, where ground subsidence is a severe environmental problem. In the case study, the model results match very well with those of the actual measurement. Two schemes of groundwater exploitation are assessed. The conclusion from the study could be used in the long-term water and economical management planning. The strategies for the control of ground subsidence are discussed. 展开更多
关键词 model loose aquifer groundwater exploitation ground subsidence control and forecast northern China's plains
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Hydraulic mechanism and time-dependent characteristics of loose gully deposits failure induced by rainfall 被引量:1
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作者 Yong Wu Siming He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第6期708-715,共8页
Failure of loose gully deposits under the effect of rainfall contributes to the potential risk of debris flow.In the past decades, researches on hydraulic mechanism and time-dependent characteristics of loosedeposits ... Failure of loose gully deposits under the effect of rainfall contributes to the potential risk of debris flow.In the past decades, researches on hydraulic mechanism and time-dependent characteristics of loosedeposits failure are frequently reported, however adequate measures for reducing debris flow are notavailable practically. In this context, a time-dependent model was established to determine the changesof water table of loose deposits using hydraulic and topographic theories. In addition, the variation inwater table with elapsed time was analyzed. The formulas for calculating hydrodynamic and hydrostaticpressures on each strip and block unit of deposit were proposed, and the slope stability and failure risk ofthe loose deposits were assessed based on the time-dependent hydraulic characteristics of establishedmodel. Finally, the failure mechanism of deposits based on infinite slope theory was illustrated, with anexample, to calculate sliding force, anti-sliding force and residual sliding force applied to each slice. Theresults indicate that failure of gully deposits under the effect of rainfall is the result of continuouslyincreasing hydraulic pressure and water table. The time-dependent characteristics of loose depositfailure are determined by the factors of hydraulic properties, drainage area of interest, rainfall pattern,rainfall duration and intensity. 展开更多
关键词 loose deposits Time-dependent characteristics Groundwater lever Hydraulic mechanism
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X-ray tomography study on the structure of the granular random loose packing 被引量:1
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作者 邢义 邱宇鹏 +2 位作者 王智 叶佳超 李向亭 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期215-218,共4页
Random loose packing is the minimum-density granular packing which can maintain mechanical stability. In this study, x-ray tomography is used to investigate the internal structure of an isotropically prepared random l... Random loose packing is the minimum-density granular packing which can maintain mechanical stability. In this study, x-ray tomography is used to investigate the internal structure of an isotropically prepared random loose packing through a special apparatus to minimize the effect of gravity. It is found that the minimum packing density is around 0.587. The microscopic structural analysis of the packing is also carried out. 展开更多
关键词 granular systems random loose packing x-ray tomography
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