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Establishment of acquired tracheoesophageal fistula using a modified magnetic compression technique in rabbits and its postmodeling evaluation
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作者 Han Meng Fu-Yao Nan +7 位作者 Na Kou Qin-Yan Hong Ming-Sheng Lv Ju-Bo Li Bao-Jie Zhang Hang Zou Lei Li Hong-Wu Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1385-1394,共10页
BACKGROUND Previous studies have validated the efficacy of both magnetic compression and surgical techniques in creating rabbit tracheoesophageal fistula(TEF)models.Magnetic compression achieves a 100%success rate but... BACKGROUND Previous studies have validated the efficacy of both magnetic compression and surgical techniques in creating rabbit tracheoesophageal fistula(TEF)models.Magnetic compression achieves a 100%success rate but requires more time,while surgery,though less frequently successful,offers rapid model establishment and technical maturity in larger animal models.AIM To determine the optimal approach for rabbit disease modeling and refine the process.METHODS TEF models were created in 12 rabbits using both the modified magnetic compression technique and surgery.Comparisons of the time to model establishment,success rate,food and water intake,weight changes,activity levels,bronchoscopy findings,white blood cell counts,and biopsies were performed.In response to the failures encountered during modified magnetic compression modeling,we increased the sample size to 15 rabbit models and assessed the repeatability and stability of the models,comparing them with the original magnetic compression technique.RESULTS The modified magnetic compression technique achieved a 66.7%success rate,whereas the success rate of the surgery technique was 33.3%.Surviving surgical rabbits might not meet subsequent experimental requirements due to TEF-related inflammation.In the modified magnetic compression group,one rabbit died,possibly due to magnet corrosion,and another died from tracheal magnet obstruction.Similar events occurred during the second round of modified magnetic compression modeling,with one rabbit possibly succumbing to aggravated lung infection.The operation time of the first round of modified magnetic compression was 3.2±0.6 min,which was significantly reduced to 2.1±0.4 min in the second round,compared to both the first round and that of the original technique.CONCLUSION The modified magnetic compression technique exhibits lower stress responses,a simple procedure,a high success rate,and lower modeling costs,making it a more appropriate choice for constructing TEF models in rabbits. 展开更多
关键词 Tracheoesophageal fistula Modified magnetic compression technique Post-modeling evaluation Pneumonia MALNUTRITION
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Non-invasive evaluation of liver steatosis with imaging modalities:New techniques and applications 被引量:3
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作者 Ke-Yu Zeng Wu-Yong-Ga Bao +4 位作者 Yun-Han Wang Min Liao Jie Yang Jia-Yan Huang Qiang Lu 《World Journal of Gastroenterology》 SCIE CAS 2023年第17期2534-2550,共17页
In the world,nonalcoholic fatty liver disease(NAFLD)accounts for majority of diffuse hepatic diseases.Notably,substantial liver fat accumulation can trigger and accelerate hepatic fibrosis,thus contributing to disease... In the world,nonalcoholic fatty liver disease(NAFLD)accounts for majority of diffuse hepatic diseases.Notably,substantial liver fat accumulation can trigger and accelerate hepatic fibrosis,thus contributing to disease progression.Moreover,the presence of NAFLD not only puts adverse influences for liver but is also associated with an increased risk of type 2 diabetes and cardiovascular diseases.Therefore,early detection and quantified measurement of hepatic fat content are of great importance.Liver biopsy is currently the most accurate method for the evaluation of hepatic steatosis.However,liver biopsy has several limitations,namely,its invasiveness,sampling error,high cost and moderate intraobserver and interobserver reproducibility.Recently,various quantitative imaging techniques have been developed for the diagnosis and quantified measurement of hepatic fat content,including ultrasound-or magnetic resonancebased methods.These quantitative imaging techniques can provide objective continuous metrics associated with liver fat content and be recorded for comparison when patients receive check-ups to evaluate changes in liver fat content,which is useful for longitudinal follow-up.In this review,we introduce several imaging techniques and describe their diagnostic performance for the diagnosis and quantified measurement of hepatic fat content. 展开更多
关键词 Non-alcoholic fatty liver disease Hepatic steatosis Imaging techniques Quantitative evaluation ULTRASOUND Quantitative ultrasound
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Durability evaluation for existing railway engineering: a review
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作者 Jiahe Wang Huajian Li +3 位作者 Chengxian Ma Chaoxun Cai Zhonglai Yi Jiaxuan Wang 《Railway Sciences》 2024年第1期59-68,共10页
Purpose – This study aims to analyze the factors, evaluation techniques of the durability of existing railwayengineering.Design/methodology/approach – China has built a railway network of over 150,000 km. Ensuring t... Purpose – This study aims to analyze the factors, evaluation techniques of the durability of existing railwayengineering.Design/methodology/approach – China has built a railway network of over 150,000 km. Ensuring thesafety of the existing railway engineering is of great significance for maintaining normal railway operationorder. However, railway engineering is a strip structure that crosses multiple complex environments. Andrailway engineering will withstand high-frequency impact loads from trains. The above factors have led todifferences in the deterioration characteristics and maintenance strategies of railway engineering compared toconventional concrete structures. Therefore, it is very important to analyze the key factors that affect thedurability of railway structures and propose technologies for durability evaluation.Findings – The factors that affect the durability and reliability of railway engineering are mainly divided intothree categories: material factors, environmental factors and load factors. Among them, material factors alsoinclude influencing factors, such as raw materials, mix proportions and so on. Environmental factors varydepending on the service environment of railway engineering, and the durability and deterioration of concretehave different failure mechanisms. Load factors include static load and train dynamic load. The on-site rapiddetection methods for five common diseases in railway engineering are also proposed in this paper. Thesemethods can quickly evaluate the durability of existing railway engineering concrete.Originality/value – The research can provide some new evaluation techniques and methods for thedurability of existing railway engineering. 展开更多
关键词 Durability assessment Existing railway engineering evaluation techniques
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Pulsed Eddy Current Non-destructive Testing and Evaluation:A Review 被引量:30
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作者 Ali Sophian Guiyun Tian Mengbao Fan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期500-514,共15页
Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed th... Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented. 展开更多
关键词 non-destructive testing - Pulsed eddy currentsMaterial characterization Structural integrity non-destructive evaluation
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Integrating multisource RS data and GIS techniques to assist the evaluation of resource-environment carrying capacity in karst mountainous area 被引量:8
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作者 PU Jun-wei ZHAO Xiao-qing +4 位作者 MIAO Pei-pei LI Si-nan TAN Kun WANG Qian TANG Wei 《Journal of Mountain Science》 SCIE CSCD 2020年第10期2528-2547,共20页
The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remo... The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remote sensing(RS)and geographic information system(GIS)provides data sources and processing platform for RECC monitoring.This study analyzed and established the evaluation index system of RECC by considering particularity in the karst mountainous area of Southwest China;processed multisource RS data(Sentinel-2,Aster-DEM and Landsat-8)to extract the spatial distributions of nine key indexes by GIS techniques(information classification,overlay analysis and raster calculation);proposed the methods of index integration and fuzzy comprehensive evaluation of the RECC by GIS;and took a typical area,Guangnan County in Yunnan Province of China,as an experimental area to explore the effectiveness of the indexes and methods.The results showed that:(1)The important indexes affecting the RECC of karst mountainous area are water resources,tourism resources,position resources,geographical environment and soil erosion environment.(2)Data on cultivated land,construction land,minerals,transportation,water conservancy,ecosystem services,topography,soil erosion and rocky desertification can be obtained from RS data.GIS techniques integrate the information into the RECC results.The data extraction and processing methods are feasible on evaluating RECC.(3)The RECC of Guangnan County was in the mid-carrying level in 2018.The midcarrying and low-carrying levels were the main types,accounting for more than 80.00%of the total study area.The areas with high carrying capacity were mainly distributed in the northern regions of the northwest-southeast line of the county,and other areas have a low carrying capacity comparatively.The coordination between regional resource-environment status and socioeconomic development is the key to improve RECC.This study explores the evaluation index system of RECC in karst mountainous area and the application of multisource RS data and GIS techniques in the comprehensive evaluation.The methods can be applied in related fields to provide suggestions for data/information extraction and integration,and sustainable development. 展开更多
关键词 Carrying capacity Multisource RS data GIS techniques evaluation index system Data Integration Karst mountainous area Fuzzy comprehensive evaluation method
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Non-destructive Evaluation of Composite Pressure Vessel by Using FBG Sensors 被引量:5
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作者 HAO Jun-cai LENG Jin-song WEI Zhang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第2期120-123,共4页
In recent years, advanced composite structures are used extensively in many industries such as aerospace, aircraft, automobile, pipeline and civil engineering. Reliability and safety are crucial requirements posed by ... In recent years, advanced composite structures are used extensively in many industries such as aerospace, aircraft, automobile, pipeline and civil engineering. Reliability and safety are crucial requirements posed by them to the advanced composite structures be- cause of their harsh working conditions. Therefore, as a very important measure, structural health monitoring (SHM) in-service is deft- nitely demanded for ensuring their safe working in-situ. In this paper, fiber Bragg grating (FBG) sensors are surface-mounted on the hoop and in the axial directions of a FRP pressure vessel to monitor the strain status during its pressurization. The experimental results show that the FBG sensors could be used to monitor the strain development and determine the ultimate failure strain of the composite pressure vessel. 展开更多
关键词 fiber optic sensor fiber Bragg grating composite pressure vessel non-destructive evaluation
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Pulsed electromagnetic non-destructive evaluation and applications 被引量:8
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作者 TIAN Guiyun ZHOU Xiuyun Ibukun D.Adewale 《Instrumentation》 2014年第1期15-28,共14页
This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This... This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This paper introduces pulsed electromagnetic techniques and their different case studies on defect detection as well as stress characterisation.Experimental tests have been validated and future research plans are discussed.This paper demonstrates pulsed electromagnetic non-destructive testing and evaluation for not only depth information,but also for multiple parameter measurement and multiple integration,which are important for future development. 展开更多
关键词 ELECTROMAGNETIC pulsed eddy current pulsed magnetic flux leakage eddy current pulsed thermography DEFECTS non-destructive testing/evaluation(NDT&E).
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New Trends in Non-Destructive Evaluation of Surface Hardened Layers and Coatings
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作者 Valery Vengrinovich 《Journal of Surface Engineered Materials and Advanced Technology》 2013年第2期154-162,共9页
This article should not be considered as a full review of current methods for non-destructive testing of surface layers. Rather, it is a subjective in this area. However, the article provides some review of the challe... This article should not be considered as a full review of current methods for non-destructive testing of surface layers. Rather, it is a subjective in this area. However, the article provides some review of the challenges posed by the current state of surface layers treatment techniques on the area of Non-Destructive materials evaluation: enhancement of the sensitivity to the type of defects, increasing resolution to submicron values, the requirement to diagnose the surface layers with depth resolution of properties, diagnosis of multilayer multicomponent surface layers and coatings, treated with concentrated energy. 展开更多
关键词 SURFACE LAYERS COATINGS PROPERTIES non-destructive evaluation
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Development of Evaluation Technique of GMAW Welding Quality Based on Statistical Analysis 被引量:3
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作者 FENG Shengqiang TERASAKI Hidenri +3 位作者 KOMIZO Yuichi HU Shengsun CHEN Donggao MA Zhihua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1257-1263,共7页
Nondestructive techniques for appraising gas metal arc welding(GMAW) faults plays a very important role in on-line quality controllability and prediction of the GMAW process. On-line welding quality controllability ... Nondestructive techniques for appraising gas metal arc welding(GMAW) faults plays a very important role in on-line quality controllability and prediction of the GMAW process. On-line welding quality controllability and prediction have several disadvantages such as high cost, low efficiency, complication and greatly being affected by the environment. An enhanced, efficient evaluation technique for evaluating welding faults based on Mahalanobis distance(MD) and normal distribution is presented. In addition, a new piece of equipment, designated the weld quality tester(WQT), is developed based on the proposed evaluation technique. MD is superior to other multidimensional distances such as Euclidean distance because the covariance matrix used for calculating MD takes into account correlations in the data and scaling. The values of MD obtained from welding current and arc voltage are assumed to follow a normal distribution. The normal distribution has two parameters: the meanm and standard deviations of the data. In the proposed evaluation technique used by the WQT, values of MD located in the range from zero tom+3s are regarded as “good”. Two experiments which involve changing the flow of shielding gas and smearing paint on the surface of the substrate are conducted in order to verify the sensitivity of the proposed evaluation technique and the feasibility of using WQT. The experimental results demonstrate the usefulness of the WQT for evaluating welding quality. The proposed technique can be applied to implement the on-line welding quality controllability and prediction, which is of great importance to design some novel equipment for weld quality detection. 展开更多
关键词 evaluation technique Mahalanobis distance normal distribution welding fault gas metal arc welding
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Phosphatidylserine:An overview on functionality,processing techniques,patents,and prospects
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作者 Jingnan Chen Jun Li +4 位作者 Haoyu Xu Jiaxi Li Yonghong Yuan Xuebing Xu Yanlan Bi 《Grain & Oil Science and Technology》 CAS 2023年第4期206-218,共13页
Phosphatidylserine(PS)is the part of cell structure in the body and has many beneficial functions especially in brain-related aging diseases.Although daily foods can provide PS to human body,the amount is very limited... Phosphatidylserine(PS)is the part of cell structure in the body and has many beneficial functions especially in brain-related aging diseases.Although daily foods can provide PS to human body,the amount is very limited due to its poverty in most foods.To overcome the issue,numerous studies based on PS have been reported to develop PS-related supplements.In this review,PS was comprehensively and critically reviewed from the view of resources,functions,processing techniques,patents,and prospects.For resources,animal,plant,and microorganism origins were all covered with their differences in composition profiles.For functions,benefits regarding memory,cognitive enhancement,exercise performance,reducing Alzheimer’s disease,and attention-deficit hyperactivity disorder symptoms were covered as well as the functional differences among animal-,plant-,and microorganism-based PS-related supplements.For processing techniques,traditional extracting methods from animal,plant,and microorganism tissues were comparatively discussed with enzymatic synthesis based on different reaction systems.Finally,patents of PS-related supplements were evaluated as well as their applications.This review could provide scientific and valuable support for PS industry. 展开更多
关键词 PHOSPHATIDYLSERINE FUNCTIONALITY Processing techniques Patents evaluation PROSPECTS
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Selecting suitable key supplier for core components during smart complex equipment central-private enterprises collaborative development process:from two different forms of evaluation information and matching perspective
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作者 HUANG Xin QI Xiaoyan +1 位作者 CHEN Hongzhuan CAI Xiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期939-954,共16页
With the development of central-private enterprises integration,selecting suitable key suppliers are able to provide core components for smart complex equipment.We consider selecting suitable key suppliers from matchi... With the development of central-private enterprises integration,selecting suitable key suppliers are able to provide core components for smart complex equipment.We consider selecting suitable key suppliers from matching perspective,for it not only satisfies natural development of smart complex equipment,it is also a good implementation of equipment project in central-private enterprises integration context.In in this paper,we carry out two parts of research,one is evaluation attributes based on comprehensive analysis,and the other is matching process between key suppliers and core components based on the matching attribute.In practical analysis process,we employ comprehensive evaluated analysis methods to acquire relevant attributes for the matching process that follows.In the analysis process,we adopt entropy-maximum deviation method(MDM)-decision-making trial and evaluation laboratory(DEMATEL)-technique for order preference by similarity to an ideal solution(TOPSIS)to obtain a comprehensive analysis.The entropy-MDM is applied to get weight value,DEMATEL is utilized to obtain internal relations,and TOPSIS is adopted to get ideal evaluated solution.We consider aggregating two types of evaluation information according to similarities of smart complex equipment based on the combination between geometric mean and arithmetic mean.Moreover,based on the aforementioned attributes and generalized power Heronian mean operator,we aggregate preference information to acquire relevant satisfaction degree,then combine the constructed matching model to get suitable key supplier.Through comprehensive analysis of selecting suitable suppliers,we know that two-sided matching and information aggregation can provide more research perspectives for smart complex equipment.Through analysis for relevant factors,we find that leading role and service level are also significant for the smart complex equipment development process. 展开更多
关键词 smart complex equipment key supplier entropymaximum deviation method(MDM) decision-making trial and evaluation laboratory(DEMATEL) technique for order preference by similarity to an ideal solution(TOPSIS) heronian mean operator central-private enterprises collaborative development
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Detection of Accidental Fish Defrosting Using Non-Destructive Ultrasonic Technique
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作者 M. Malainine B. Faiz +4 位作者 A. Moudden D. Decultot D. Izbaim G. Maze I. Aboudaoud 《Journal of Food Science and Engineering》 2011年第1期20-26,共7页
A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backsca... A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backscattered by fish are recorded during thawing. The comparison of the evolution curves and images corresponding to first and second thawing shows indicators of accidental thawing. The monitoring of thawing process showed that its assessment can be reduced to the measurement of the water content lost by fish. The attempt to replace the original water lost by fish in first thawing is analyzed. The influence of the transducer frequency on fish thawing evaluation is tested. 展开更多
关键词 ULTRASOUND non-destructive evaluation fish defrosting thawing process
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A supercritical CO_2 fluid technique for the preparation and evaluation of rhBMP-2-loaded PLLA microspheres
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作者 Jiang Wu1,Yunqing Kang2,Guangfu Yin2,Huaiqing Chena(aInstitute of Biomedical Engineering,West China Center of Medical Sciences,Sichuan University,Chengdu 610041,bCollege of Materials Science and Engineering, Sichuan University,Chengdu 610064) 《医用生物力学》 EI CAS CSCD 2009年第S1期114-114,共1页
Introduction The use of supercritical fluids such as supercritical CO<sub>2</sub>(scCO<sub>2</sub>) has provided a ’clean’ and effective alternative to traditional methods of protein delive... Introduction The use of supercritical fluids such as supercritical CO<sub>2</sub>(scCO<sub>2</sub>) has provided a ’clean’ and effective alternative to traditional methods of protein delivery systems.Here。 展开更多
关键词 PLLA A supercritical CO2 fluid technique for the preparation and evaluation of rhBMP-2-loaded PLLA microspheres SEDS CO
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Study on the Latter Stage Evaluation to Technique Import Project
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作者 SHI Bao-juan ZHAO Guo-jie WANG Wei 《Chinese Business Review》 2007年第1期61-64,80,共5页
How's the effect of technical import actually? The latter stage evaluation to technique import project is necessary to get the answer. Therefore, the latter stage evaluation to technique import project is not equal ... How's the effect of technical import actually? The latter stage evaluation to technique import project is necessary to get the answer. Therefore, the latter stage evaluation to technique import project is not equal to the latter stage evaluation to general construction projects, it doesn't emphasize particularly on its economic profits but the performance of the digest, generalization, improvement and redevelopment of the imported technique. 展开更多
关键词 technical import technique import project the latter stage evaluation
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An appropriate prediction technique in ground water evaluation
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《Global Geology》 1998年第1期95-96,共2页
关键词 An appropriate prediction technique in ground water evaluation
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Value of helical CT volume rendering technique in post-operative evaluation of screw in screw fixation of axis fractures
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作者 许崇永 《外科研究与新技术》 2005年第3期173-173,共1页
To explore the value of helical CT volume rendering technique (VRT) in post-operative evaluation of screw fixation of axis fractures.Methods There were 21 cases of screw fixation of axis fractures between February 200... To explore the value of helical CT volume rendering technique (VRT) in post-operative evaluation of screw fixation of axis fractures.Methods There were 21 cases of screw fixation of axis fractures between February 2002 and May 2004 in the study including six cases with fractures on axis body,five on odontoid process and 10 on axis body and odontoid process.All cases received X-ray plain film,helical CT scanning,multi-planar reformatting(MPR) and VRT.Results Screw fixation through axis body and massa lateralis atlantis was performed in 10 cases and that through axis body and odontoid process in 11.VRT could clearly display full aperture of screw orbit,location of screw and angle of fixation and hence was superior to X-ray plain film and MPR.Multi-angle VRT displayed asymmetrical space of odontoid process and massa lateralis atlantis in four cases and medial deviation of 2~5 mm of half screw in screw fixation through axis body and massa lateralis atlantis in six.Conclusion VRT can eliminate false shadow of fixation screw,clearly display full aperture of screw orbit and hence supply improtant imaging evidence for post-operative evaluation of screw fixation of axis fractures.7 refs,1 fig,1 tab. 展开更多
关键词 Value of helical CT volume rendering technique in post-operative evaluation of screw in screw fixation of axis fractures
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Complex Exploration Techniques for the Low-permeability Lithologic Gas Pool in the Upper Paleozoic of Ordos Basin 被引量:9
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作者 FuJinhua XiShengli LiuXinshe SunLiuyi 《Petroleum Science》 SCIE CAS CSCD 2004年第2期111-118,共8页
The Ordos basin is a stable craton whose late Paleozoic undergoes two sedimentary stages: from the middle- late Carboniferous offshore plain to the Permian continental river and lake delta. Sandstones in delta plain c... The Ordos basin is a stable craton whose late Paleozoic undergoes two sedimentary stages: from the middle- late Carboniferous offshore plain to the Permian continental river and lake delta. Sandstones in delta plain channels, delta-front river mouth bars and tidal channels are well developed. The sandstones are distributed on or between the genetic source rocks, forming good gas source conditions with widespread subtle lithologic gas pools of low porosity, low permeability, low pressure and low abundance. In recent years, a series of experiments has been done, aimed at overcoming difficulties in the exploration of lithologic gas pools. A set of exploration techniques, focusing on geological appraisal, seismic exploration, accurate logging evaluation and interpretation, well testing fracturing, has been developed to guide the exploration into the upper Paleozoic in the basin, leading to the discoveries of four large gas fields: Sulige, Yulin, Wushenqi and Mizhi. 展开更多
关键词 Ordos Basin upper Paleozoic lithologic gas pool seismic exploration accurate logging evaluation exploration techniques
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A new framework for evaluation of rock fragmentation in open pit mines 被引量:4
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作者 Mohammad Babaeian Mohammad Ataei +2 位作者 Farhang Sereshki Farzad Sotoudeh Sadjad Mohammadi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第2期325-336,共12页
The main purpose of blasting in open pit mines is to produce the feed for crushing stage with the optimum dimensions from in situ rocks. The size distribution of muck pile indicates the efficiency of blasting pattern ... The main purpose of blasting in open pit mines is to produce the feed for crushing stage with the optimum dimensions from in situ rocks. The size distribution of muck pile indicates the efficiency of blasting pattern to reach the required optimum sizes. Nevertheless, there is no mature model to predict fragmentation distribution to date that can be used in various open pit mines. Therefore, a new framework to evaluate and predict fragmentation distribution is presented based on the image analysis approach. For this purpose, the data collected from Jajarm bauxite mine in Iran were used as the sources in this study. The image analysis process was performed by Split-Desktop software to find out fragmentation distribution, uniformity index and average size of the fragmented rocks. Then, two different approaches including the multivariate regression method and the decision-making trial and evaluation laboratory(DEMATEL) technique were incorporated to develop new models of the uniformity index and the average size to improve the Rosin-Rammler function. The performances of the proposed models were evaluated in four blasting operation sites. The results obtained indicate that the regression model possesses a better performance in prediction of the uniformity index and the average size and subsequently the fragmentation distribution in comparison with DEMATEL and conventional Rosin-Rammler models. 展开更多
关键词 Rock FRAGMENTATION Image analysis Open PIT mine Split-desktop software package Decision-making TRIAL and evaluation laboratory(DEMATEL)technique
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Optimization of CO_2 separation technologies for Chinese refineries based on a fuzzy comprehensive evaluation model 被引量:2
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作者 Qian-Qian Song Qing-Zhe Jiang Zhao-Zheng Song 《Petroleum Science》 SCIE CAS CSCD 2015年第1期197-206,共10页
This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristic... This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption (PSA), chemical absorption (CA), and membrane absorption (MA). Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA. 展开更多
关键词 Chinese refineries CO2 emission Separation technique Economic evaluation AHP-entropy method Fuzzy comprehensive evaluation model
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Threat evaluation method of warships formation air defense based on AR(p)-DITOPSIS 被引量:3
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作者 SUN Haiwen XIE Xiaofang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期297-307,共11页
For the target threat evaluation of warships formation air defense, the sample data are frequently insufficient and even incomplete. The existing evaluation methods rely too much on expertise and are difficult to carr... For the target threat evaluation of warships formation air defense, the sample data are frequently insufficient and even incomplete. The existing evaluation methods rely too much on expertise and are difficult to carry out for the dynamic evaluation on time series. In order to solve these problems, a threat evaluation method based on the AR(p)(auto regressive(AR))-dynamic improved technique for order preference by similarity to ideal solution(DITOPSIS) method is proposed. The AR(p) model is adopted to predict the missing data on the time series. Then, the entropy weight method is applied to solve each index weight at the objective point. Kullback-Leibler divergence(KLD) is used to improve the traditional TOPSIS, and to carry out the target threat evaluation. The Poisson distribution is used to assign the weight value.Simulation results show that the improved AR(p)-DITOPSIS threat evaluation method can synthetically take into account the target threat degree in time series and is more suitable for the threat evaluation under the condition of missing the target data than the traditional TOPSIS method. 展开更多
关键词 AR(p) model Kullback-Leibler DIVERGENCE (KLD) dynamic improved technique for order PREFERENCE by similarity to ideal solution (DITOPSIS) time series THREAT evaluation
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