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地面AHDOS4.0版程序机审报表的几个问题
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作者 刘建国 《福建气象》 2001年第1期28-28,共1页
经过几年人工和计算机审核的对比,暂时发现地面AHDOS4.0版程序审核气表-1,有如下几个问题:
关键词 程序机 地面 报表 气表-1 计算机 审核
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Prediction of Injection-Production Ratio with BP Neural Network
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作者 袁爱武 郑晓松 王东城 《Petroleum Science》 SCIE CAS CSCD 2004年第4期62-65,共4页
Injection of water to enhance oil production is commonplace, and improvements in understanding the process are economically important. This study examines predictive models of the injection-to-production ratio. First... Injection of water to enhance oil production is commonplace, and improvements in understanding the process are economically important. This study examines predictive models of the injection-to-production ratio. Firstly, the error between the fitting and actual injection-production ratio is calculated with such methods as the injection-production ratio and water-oil ratio method, the material balance method, the multiple regression method, the gray theory GM (1,1) model and the back-propogation (BP) neural network method by computer applications in this paper. The relative average errors calculated are respectively 1.67%, 1.08%, 19.2%, 1.38% and 0.88%. Secondly, the reasons for the errors from different prediction methods are analyzed theoretically, indicating that the prediction precision of the BP neural network method is high, and that it has a better self-adaptability, so that it can reflect the internal relationship between the injection-production ratio and the influencing factors. Therefore, the BP neural network method is suitable to the prediction of injection-production ratio. 展开更多
关键词 Injection-production ratio (IPR) BP neural network gray theory PREDICTION
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10 Gbit/s PRBS tester implemented in FPGA 被引量:1
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作者 苗澎 王志功 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期516-519,共4页
The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BI... The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BIP-8) error detector is presented. Implemented in a parallel feedback configuration, this tester features PRBS generation of sequences with bit lengths of 2^7 - 1,2^10- 1,2^15 - 1,2^23 - land 2^31 - 1 for up to 10 Gbit/s applications with a 10 Gbit/s optical transceiver, via the SFI-4 (OC-192 serdes-framer interface). In the OC-192 frame alignment circuit, a dichotomy search algorithm logic which performs the functions of word alignment and STM-64/OC192 de-frame speeds up the frame sync logic and reduces circuit complexity greatly. The system can be used as a low cost tester to evaluate the performance of OC-192 devices and components, taking the replacement of precious commercial PRBS testers. 展开更多
关键词 bit interleaved polarity 8 BIP-8 synchronous digital hierarchy SDH FRAMER field programmable gate array (FPGA) pseudo-random binary sequence (PRBS)
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Cortical stimulation for treatment of neurological disorders of hyperexcitability: a role of homeostatic plasticity 被引量:2
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作者 Zhi Chai Cungen Ma Xiaoming Jin 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第1期34-38,共5页
Hyperexcitability of neural network is a key neurophysiological mechanism in several neurological disorders including epilepsy, neuropathic pain, and tinnitus. Although standard paradigm of pharmacological management ... Hyperexcitability of neural network is a key neurophysiological mechanism in several neurological disorders including epilepsy, neuropathic pain, and tinnitus. Although standard paradigm of pharmacological management of them is to suppress this hyperexcitability, such as having been exemplified by the use of certain antiepileptic drugs, their frequent refractoriness to drug treatment suggests likely different pathophysiological mechanism. Because the pathogenesis in these disorders exhibits a transition from an initial activity loss after injury or sensory deprivation to subsequent hyperexcitability and paroxysmal discharges, this process can be regarded as a process of functional compensation similar to homeostatic plasticity regulation, in which a set level of activity in neural network is maintained after injury-induced activity loss through enhanced network excitability. Enhancing brain activity, such as cortical stimulation that is found to be effective in relieving symptoms of these disorders, may reduce such hyperexcitability through homeostatic plasticity mechanism. Here we review current evidence of homeostatic plasticity in the mechanism of acquired epilepsy, neuropathic pain, and tinnitus and the effects and mechanism of cortical stimulation. Establishing a role of homeostatic plasticity in these disorders may provide a theoretical basis on their pathogenesis as well as guide the development and application of therapeutic approaches through electrically or pharmacologically stimulating brain activity for treating these disorders. 展开更多
关键词 homeostatic plasticity EPILEPSY neuropathic pain cerebral cortex HYPEREXCITABILITY brain injury TINNITUS cortical stimulation
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An Enhanced Hadoop Heartbeat Mechanism for MapReduce Task Scheduler Using Dynamic Calibration 被引量:3
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作者 Xinzhu Lu Keatkeong Phang 《China Communications》 SCIE CSCD 2018年第11期93-110,共18页
MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a hea... MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a heartbeat mechanism for MapReduce Task Scheduler using Dynamic Calibration (HMTS- DC) is proposed to address the unbalanced node computation capacity problem in a het- erogeneous MapReduce environment. HMTS- DC uses two mechanisms to dynamically adapt and balance tasks assigned to each com- pute node: 1) using heartbeat to dynamically estimate the capacity of the compute nodes, and 2) using data locality of replicated data blocks to reduce data transfer between nodes. With the first mechanism, based on the heart- beats received during the early state of the job, the task scheduler can dynamically estimate the computational capacity of each node. Us- ing the second mechanism, unprocessed Tasks local to each compute node are reassigned and reserved to allow nodes with greater capacities to reserve more local tasks than their weaker counterparts. Experimental results show that HMTS-DC performs better than Hadoop and Dynamic Data Placement Strategy (DDP) in a dynamic environment. Furthermore, an en- hanced HMTS-DC (EHMTS-DC) is proposed bv incorporatin historical data. In contrastto the "slow start" property of HMTS-DC, EHMTS-DC relies on the historical computation capacity of the slave machines. The experimental results show that EHMTS-DC outperforms HMTS-DC in a dynamic environment. 展开更多
关键词 dynamic load-balancing HADOOP MAPREDUCE replication mechanism heartbeatnechanism
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Research on extended AHP method with the aid of RST 被引量:2
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作者 倪明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第1期45-49,共5页
Analytic Hierarchy Process (AHP) method can be used to solve the tasks of multi-criterion decision system fields, but some complicated questions processed by AHP cannot be easily solved by means of the general method.... Analytic Hierarchy Process (AHP) method can be used to solve the tasks of multi-criterion decision system fields, but some complicated questions processed by AHP cannot be easily solved by means of the general method. It is because of being unsatisfied with consistency condition or judgment matrix too intricate to solve, which causes AHP invalidation. So in order to resolve this problem, AHP knowledge systems reduced with the aid of Genetic Algorithms (GA) were proposed, which directly acquired the order of AHP issue through the rule of Rough Sets Theory (RST) method, or solved the tasks reduced by RST with classical AHP method. On this condition, the compare decision system of region informatization level was solved, and the results solved were the same to those by classical AHP, which denoted that this method was more simple and reliable, besides the four rules of changing AHP system into RST Decision System. 展开更多
关键词 Rough sets theory (RST) genetic algorithms (CA) analytic hierarchy process (AHP) regioninformatization level
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Deterministic and randomized scheduling problems under the lp norm on two identical machines 被引量:5
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作者 林凌 谈之奕 何勇 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第1期20-26,共7页
Parallel machine scheduling problems, which are important discrete optimization problems, may occur in many applications. For example, load balancing in network communication channel assignment, parallel processing in... Parallel machine scheduling problems, which are important discrete optimization problems, may occur in many applications. For example, load balancing in network communication channel assignment, parallel processing in large-size computing, task arrangement in flexible manufacturing systems, etc., are multiprocessor scheduling problem. In the traditional parallel machine scheduling problems, it is assumed that the problems are considered in offline or online environment. But in practice, problems are often not really offline or online but somehow in-between. This means that, with respect to the online problem, some further information about the tasks is available, which allows the improvement of the performance of the best possible algorithms. Problems of this class are called semi-online ones. In this paper, the semi-online problem P2|decr|lp (p>1) is considered where jobs come in non-increasing order of their processing times and the objective is to minimize the sum of the lp norm of every machine’s load. It is shown that LS algorithm is optimal for any lp norm, which extends the results known in the literature. Furthermore, randomized lower bounds for the problems P2|online|lp and P2|decr|lp are presented. 展开更多
关键词 SEMI-ONLINE SCHEDULING RANDOMIZATION Competitive ratio
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Single-machine scheduling of two activities with slack: CPM to minimize the total tardiness 被引量:1
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作者 李星梅 乞建勋 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期97-100,共4页
In a CPM network, the longest path problem is one of the most important subjects. According to the intrinsic principle of CPM network, the length of the paths between arbitrary two nodes is presented. Furthermore, the... In a CPM network, the longest path problem is one of the most important subjects. According to the intrinsic principle of CPM network, the length of the paths between arbitrary two nodes is presented. Furthermore, the length of the longest path from start node to arbitrary node and from arbitrary node to end node is proposed. In view of a scheduling problem of two activities with float in the CPM scheduling, we put forward Barycenter Theory and prove this theory based on the algorithm of the length of the longest path. By this theory, we know which activity should be done firstly. At last, we show our theory by an example. 展开更多
关键词 CPM SCHEDULING SINGLE-MACHINE Activity float
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Abdominal aortic aneurysm: Treatment options, image visualizations and follow-up procedures 被引量:4
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作者 Zhong-Hua Sun 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2012年第1期49-60,共12页
Abdominal aortic aneurysm is a common vascular disease that affects elderly population.Open surgical repair is regarded as the gold standard technique for treatment of abdominal aortic aneurysm,however,endovaseular an... Abdominal aortic aneurysm is a common vascular disease that affects elderly population.Open surgical repair is regarded as the gold standard technique for treatment of abdominal aortic aneurysm,however,endovaseular aneurysm repair has rapidly expanded since its first introduction in 1990s.As a less invasive technique,endovascular aneurysm repair has been confirmed to be an effective alternative to open surgical repair,especially in patients with co-morbid conditions.Computed tomography (CT) angiography is currently the preferred imaging modality for both preoperative planning and post-operative follow-up.2D CT images are complemented by a number of 3D reconstructions which enhance the diagnostic applications of CT angiography in both planning and follow-up of endovascular repair.CT has the disadvantage of high cummulative radiation dose,of particular concern in younger patients,since patients require regular imaging follow-ups after endovascular repair,thus,exposing patients to repeated radiation exposure for life.There is a trend to change from CT to ultrasound surveillance of endovascular aneurysm repair.Medical image visualizations demonstrate excellent morphological assessment of aneurysm and stent-grafts,but fail to provide hemodynamic changes caused by the complex stent-graft device that is implanted into the aorta.This article reviews the treatment options of abdominal aortic aneurysm,various image visualization tools,and follow-up procedures with use of different modalities including both imaging and computational fluid dynamics methods.Future directions to improve treatment outcomes in the follow-up of endovascular aneurysm repair are outlined. 展开更多
关键词 Abdominal aortic aneurysm Computed tomography FOLLOW-UP Stent graft TREATMENT Visualization.
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The Use of Drones in Forestry 被引量:4
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作者 Tiberiu Paul Banu Gheorghe Florian Borlea Constantin Banu 《Journal of Environmental Science and Engineering(B)》 2016年第11期557-562,共6页
Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that... Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that can be collected flexibly in a short time and at a relatively low price. Also, drones have an important role in filling the gaps of common data collected using manned aircraft or satellite remote sensing, while having many advantages both in research and in various practical applications particularly in forestry as well as in land use in general. This paper aims to briefly describe the different approaches of applications of UAVs (Unmanned Aircraft Vehicles) in forestry, such as forest mapping, forest management planning, canopy height model creation or mapping forest gaps. These approaches have great potential in the near future applications and their quick implementation in a variety of situations is desirable for the sustainable management of forests. 展开更多
关键词 DRONES UAV remote sensing forest management.
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Computation of the Simplest Normal Forms for Resonant Double Hopf Bifurcations System Based on Lie Transform 被引量:2
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作者 张琪昌 何学军 郝淑英 《Transactions of Tianjin University》 EI CAS 2006年第3期180-185,共6页
The simplest normal form of resonant double Hopf bifurcation was studied based on Lie operator. The coefficients of the simplest normal forms of resonant double Hopf bifurcation and the nonlinear transformations in te... The simplest normal form of resonant double Hopf bifurcation was studied based on Lie operator. The coefficients of the simplest normal forms of resonant double Hopf bifurcation and the nonlinear transformations in terms of the original system coefficients were given explicitly. The nonlinear transformations were used for reducing the lower- and higher-order normal forms, and the rank of system matrix was used to determine the coefficient of normal form which could be reduced. These make the gained normal form simpler than the traditional one. A general program was compiled with Mathematica. This program can compute the simplest normal form of resonant double Hopf bifurcation and the non-resonant form up to the 7th order. 展开更多
关键词 nonlinear systems normal form bifurcation mathematical transformations Lie operator computer program
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Numerical Investigation of Fuel Dilution Effects on the Performance of the Conventional and the Highly Preheated and Diluted Air Combustion Furnaces 被引量:4
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作者 Kiomars Abbasi Khazaei Ali Asghar Hamidi Masoud Rahimi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期711-726,共16页
This numerical study investigates the effects of using a diluted fuel (50% natural gas and 50% N2) in an industrial furnace under several cases of conventional combustion (air with 21% O2 at 300 and 1273 K) and th... This numerical study investigates the effects of using a diluted fuel (50% natural gas and 50% N2) in an industrial furnace under several cases of conventional combustion (air with 21% O2 at 300 and 1273 K) and the highly preheated and diluted air (1273 K with 10% O2 and 90% N2) combustion (HPDAC) conditions using an in-house computer program. It was found that by applying a combined diluted fuel and oxidant instead of their uncombined and/or undiluted states, the best condition is obtained for the establishment of HPDAC's main unique features. These features are low mean and maximum gas temperature and high radiation/total heat transfer to gas and tubes; as well as more uniformity of theirs distributions which results in decrease in NOx pollutant formation and increase in furnace efficiency or energy saving. Moreover, a variety of chemical flame shape, the process fluid and tubes walls temperatures profiles, the required regenerator efficiency and finally the concentration and velocity patterns have been also qualitatively/quantitatively studied. 展开更多
关键词 highly preheated and diluted air combustion furnace numerical modeling chemical flame fuel dilution NOx formation energy saving
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Computer Programs for Prediction of Mining Area Deformation with Time Factor Taken into Consideration 被引量:2
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作者 BIALEK Jan 《Journal of China University of Mining and Technology》 2002年第1期6-11,共6页
This paper discussed the current of works on computerisation of all problems related to mining subsidence, including the time factor,carried out in the Division of Mining Geodesy of Technical University of Silesia, Po... This paper discussed the current of works on computerisation of all problems related to mining subsidence, including the time factor,carried out in the Division of Mining Geodesy of Technical University of Silesia, Poland. First, the formulas implemented in the programs were presented. These formulas considerably increase the description accuracy of final deformations by taking into uncaved strip along extraction rib (extraction margin). They also improve the deformation description of areas located far from the extraction place. Then, the research results aiming to improving the description of deformation with time were introduced. Finally, the Windows based version of the program for the creation of mining geological opinions were presented in the form accepted by Mining Offices of Poland. 展开更多
关键词 mining subsidence PROGRAM time factor
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Effect of cross-wind on spatial vibration responses of train and track system 被引量:4
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作者 向俊 赫丹 曾庆元 《Journal of Central South University》 SCIE EI CAS 2009年第3期520-524,共5页
By taking cross-wind forces acting on trains into consideration, a dynamic analysis method of the cross-wind and high-speed train and slab track system was proposed on the basis of the analysis theory of spatial vibra... By taking cross-wind forces acting on trains into consideration, a dynamic analysis method of the cross-wind and high-speed train and slab track system was proposed on the basis of the analysis theory of spatial vibration of high-speed train and slab track system. The corresponding computer program was written by FORTRAN language. The dynamic responses of the high-speed train and slab track under cross-wind action were calculated. Meanwhile, the effects of the cross-wind on the dynamic responses of the system were also analyzed. The results show that the cross-wind has a significant influence on the lateral and vertical displacement responses of the car body, load reduction factor and overturning factor. For example, the maximum lateral displacement responses of the car body of the first trailer with and without cross-wind forces are 32.10 and 1.60 mm, respectively. The maximum vertical displacement responses of the car body of the first trailer with and without cross-wind forces are 6.60 and 3.29 mm, respectively. The maximum wheel load reduction factors of the first trailer with and without cross-wind forces are 0.43 and 0.22, respectively. The maximum overturning factors of the first trailer with and without cross-wind forces are 0.28 and 0.08, respectively. The cross-wind affects the derailment factor and lateral Sperling factor of the moving train to a certain extent. However, the lateral and vertical displacement responses of rails with the crnss-wind are almost the same as those without the cross-wind. The method presented and the corresponding computer program can be used to calculate the interaction between trains and track in cross-wind. 展开更多
关键词 slab track high-speed train cross-wind spatial vibration DISPLACEMENT dynamic responses
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Performance Calibration of Articulated Arm Coordinate Measuring Machine 被引量:5
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作者 Unai Mutilba Gorka Kortaberria Aitor Olarra Antonio Gutierrez 《Journal of Mechanics Engineering and Automation》 2013年第10期602-608,共7页
This paper presents the method for the performance calibration of AACMM (articulated arm coordinate measuring machines) according to ASME B89.4.22 Standard. The growing use of this class of measurement equipment has... This paper presents the method for the performance calibration of AACMM (articulated arm coordinate measuring machines) according to ASME B89.4.22 Standard. The growing use of this class of measurement equipment has been accompanied by an absence of authorized laboratories to provide calibration certificates for its performance. Due to ASME B89.4.22 and VD12617-9 are nowadays the unique standards in the field of AACMM verification, IK4 Tekniker has compared both of them in order to develop internal test procedures to yield reliable performance calibration results. As a result, IK4 Tekniker has been recognized by the Spanish Accreditation Body (ENAC) in the field of AACMM calibration. Internal test procedures and uncertainty evaluation analysis have been developed as well as ENAC certificated reference test equipments have been acquired to ensure a suitable AACMM calibration process. 展开更多
关键词 AACMM performance calibration ASME B89.4.22 ENAC UNCERTAINTY
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TEST COVERAGE ANALYSIS BASED ON PROGRAM SLICING 被引量:1
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作者 Chen Zhenqiang Xu Baowen Guanjie (Dept. of Computer Science & Eng., Southeast Univ., Nanjing 210096) (State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072) (Jiangsu Key Lab. of Computer Info. Proc. Tech., Soochow Univ., Suzhou 215006) 《Journal of Electronics(China)》 2003年第3期232-236,共5页
Coverage analysis is a structural testing technique that helps to eliminate gaps in atest suite and determines when to stop testing. To compute test coverage, this letter proposes anew concept coverage about variables... Coverage analysis is a structural testing technique that helps to eliminate gaps in atest suite and determines when to stop testing. To compute test coverage, this letter proposes anew concept coverage about variables, based on program slicing. By adding powers accordingto their importance, the users can focus on the important variables to obtain higher test coverage.The letter presents methods to compute basic coverage based on program structure graphs. Inmost cases, the coverage obtained in the letter is bigger than that obtained by a traditionalmeasure, because the coverage about a variable takes only the related codes into account. 展开更多
关键词 Software testing Testing coverage Program slicing
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Strategies and Principles of Distributed Machine Learning on Big Data 被引量:17
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作者 Eric P. Xing Qirong Ho +1 位作者 Dai Wei Pengtao Xie 《Engineering》 SCIE EI 2016年第2期179-195,共17页
The rise of big data has led to new demands for machine learning (ML) systems to learn complex mod- els, with millions to billions of parameters, that promise adequate capacity to digest massive datasets and offer p... The rise of big data has led to new demands for machine learning (ML) systems to learn complex mod- els, with millions to billions of parameters, that promise adequate capacity to digest massive datasets and offer powerful predictive analytics (such as high-dimensional latent features, intermediate repre- sentations, and decision functions) thereupon. In order to run ML algorithms at such scales, on a distrib- uted cluster with tens to thousands of machines, it is often the case that significant engineering efforts are required-and one might fairly ask whether such engineering truly falls within the domain of ML research. Taking the view that "big" ML systems can benefit greatly from ML-rooted statistical and algo- rithmic insights-and that ML researchers should therefore not shy away from such systems design-we discuss a series of principles and strategies distilled from our recent efforts on industrial-scale ML solu- tions. These principles and strategies span a continuum from application, to engineering, and to theo- retical research and development of big ML systems and architectures, with the goal of understanding how to make them efficient, generally applicable, and supported with convergence and scaling guaran- tees. They concern four key questions that traditionally receive little attention in ML research: How can an ML program be distributed over a cluster? How can ML computation be bridged with inter-machine communication? How can such communication be performed? What should be communicated between machines? By exposing underlying statistical and algorithmic characteristics unique to ML programs but not typically seen in traditional computer programs, and by dissecting successful cases to reveal how we have harnessed these principles to design and develop both high-performance distributed ML software as well as general-purpose ML frameworks, we present opportunities for ML researchers and practitioners to further shape and enlarge the area that lies between ML and systems.. 展开更多
关键词 Machine learningArtificial intelligence big dataBig modelDistributed systemsPrinciplesTheoryData-parallelismModel-parallelism
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Developing a Computer Program for Detailed Study of Planing Hull's Spray Based on Morabito's Approach 被引量:2
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作者 Parviz Ghadimi Sasan Tavakoli +1 位作者 Abbas Dashtimanesh Arya Pirooz 《Journal of Marine Science and Application》 2014年第4期402-415,共14页
Recently, Morabito(2010) has studied the water spray phenomena in planing hulls and presented new analytical equations. However, these equations have not been used for detailed parametric studies of water spray around... Recently, Morabito(2010) has studied the water spray phenomena in planing hulls and presented new analytical equations. However, these equations have not been used for detailed parametric studies of water spray around planing hulls. In this paper, a straight forward analysis is conducted to apply these analytical equations for finding the spray geometry profile by developing a computer program based on presented computational process. The obtained results of the developed computer program are compared against existing data in the literature and favorable accuracy is achieved. Parametric studies have been conducted for different physical parameters. Positions of spray apex are computed and three dimensional profiles of spray are examined. It is concluded that spray height increases by an increase in the speed coefficient or the deadrise angle. Ultimately, a computational process is added to Savitsky's method and variations of spray apex are computed for different velocities. It is shown that vertical, lateral, and longitudinal positions of spray increase as the craft speed increases. On the other hand, two new angles are defined in top view and it is concluded that they have direct relation with the trim angle. However, they show inverse relation with the deadrise angle. 展开更多
关键词 SPRAY prismatic planing hull mathematical modeling water spray parametric study
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Measurement and evaluation of strain fields in T23 steel based on digital image correlation method 被引量:1
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作者 林烈雄 徐孟嘉 +4 位作者 徐济进 陆皓 叶诚辉 余春 陈俊梅 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期1977-1985,共9页
Surface strain fields of the designed compact tension(CT)specimens were investigated by digital image correlation(DIC)method.An integrative computer program was developed based on DIC algorithms to characterize the st... Surface strain fields of the designed compact tension(CT)specimens were investigated by digital image correlation(DIC)method.An integrative computer program was developed based on DIC algorithms to characterize the strain fields accurately and graphically.Strain distribution of the CT specimen was predicted by finite element method(FEM).Good agreement is observed between the surface strain fields measured by DIC and predicted by FEM,which reveals that the proposed method is practical and effective to determine the strain fields of CT specimens.Moreover,strain fields of the CT specimens with various compressive loads and notch diameters were studied by DIC.The experimental results can provide effective reference to usage of CT specimens in triaxial creep test by appropriately selecting specimen and experiment parameters. 展开更多
关键词 digital image correlation strain fields T23 steel compact tension specimen finite element simulation
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Two-stage vs single-stage management for concomitant gallstones and common bile duct stones 被引量:108
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作者 Jiong Lu Yao Cheng +3 位作者 Xian-Ze Xiong Yi-Xin Lin Si-Jia Wu Nan-Sheng Cheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第24期3156-3166,共11页
AIM:To evaluate the safety and effectiveness of twostage vs single-stage management for concomitant gallstones and common bile duct stones.METHODS:Four databases,including PubMed,Embase,the Cochrane Central Register o... AIM:To evaluate the safety and effectiveness of twostage vs single-stage management for concomitant gallstones and common bile duct stones.METHODS:Four databases,including PubMed,Embase,the Cochrane Central Register of Controlled Trials and the Science Citation Index up to September 2011,were searched to identify all randomized controlled trials(RCTs).Data were extracted from the studies by two independent reviewers.The primary outcomes were stone clearance from the common bile duct,postoperative morbidity and mortality.The secondary outcomes were conversion to other procedures,number of procedures per patient,length of hospital stay,total operative time,hospitalization charges,patient acceptance and quality of life scores.RESULTS:Seven eligible RCTs [five trials(n = 621) comparing preoperative endoscopic retrograde cholangiopancreatography(ERCP)/endoscopic sphincterotomy(EST) + laparoscopic cholecystectomy(LC) with LC + laparoscopic common bile duct exploration(LCBDE);two trials(n = 166) comparing postoperative ERCP/EST + LC with LC + LCBDE],composed of 787 patients in total,were included in the final analysis.The metaanalysis detected no statistically significant difference between the two groups in stone clearance from the common bile duct [risk ratios(RR) =-0.10,95% confidence intervals(CI):-0.24 to 0.04,P = 0.17],postoperative morbidity(RR = 0.79,95% CI:0.58 to 1.10,P = 0.16),mortality(RR = 2.19,95% CI:0.33 to 14.67,P = 0.42),conversion to other procedures(RR = 1.21,95% CI:0.54 to 2.70,P = 0.39),length of hospital stay(MD = 0.99,95% CI:-1.59 to 3.57,P = 0.45),total operative time(MD = 12.14,95% CI:-1.83 to 26.10,P = 0.09).Two-stage(LC + ERCP/EST) management clearly required more procedures per patient than single-stage(LC + LCBDE) management.CONCLUSION:Single-stage management is equivalent to two-stage management but requires fewer procedures.However,patient's condition,operator's expertise and local resources should be taken into account in making treatment decisions. 展开更多
关键词 Laparoscopic cholecystectomy Laparoscop-ic common bile duct exploration Endoscopic retrogradecholangiopancreatography Endoscopic sphincterotomy GALLSTONES Common bile duct stones META-ANALYSIS
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