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基于目标的教学与评价 被引量:2
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作者 岳廷玉 《生活教育》 2018年第1期105-106,共2页
教学目标的性质,决定了制定教学目标必须把握其有效性,这有利于课堂教学的目标导向,有利于教学过程的可操作性,有利于教学目标向学习目标的转化,有利于课堂测评的可操作性。
关键词 导向性 可操作 可评价
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Bus transit travel time reliability evaluation based on automatic vehicle location data 被引量:4
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作者 严亚丹 过秀成 +2 位作者 李岩 孔哲 何明 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期100-105,共6页
In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed a... In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed and evaluated based on automatic vehicle location (AVL) data. Based on the statistical analysis of the bus transit travel time, six indices including the coefficient of variance, the width of travel time distribution, the mean commercial speed, the congestion frequency, the planning time index and the buffer time index are proposed. Moreover, a framework for evaluating bus transit travel time reliability is constructed. Finally, a case study on a certain bus route in Suzhou is conducted. Results show that the proposed evaluation index system is simple and intuitive, and it can effectively reflect the efficiency and stability of bus operations. And a distinguishing feature of bus transit travel time reliability is the temporal pattern. It varies across different time periods. 展开更多
关键词 bus transit travel time reliability evaluation andanalysis automatic vehicle location data statistical analysis
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Intelligibility evaluation of enhanced whisper in joint time-frequency domain 被引量:1
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作者 周健 魏昕 +1 位作者 梁瑞宇 赵力 《Journal of Southeast University(English Edition)》 EI CAS 2014年第3期261-266,共6页
Some factors influencing the intelligibility of the enhanced whisper in the joint time-frequency domain are evaluated. Specifically, both the spectrum density and different regions of the enhanced spectrum are analyze... Some factors influencing the intelligibility of the enhanced whisper in the joint time-frequency domain are evaluated. Specifically, both the spectrum density and different regions of the enhanced spectrum are analyzed. Experimental results show that for a spectrum of some density, the joint time-frequency gain-modification based speech enhancement algorithm achieves significant improvement in intelligibility. Additionally, the spectrum region where the estimated spectrum is smaller than the clean spectrum, is the most important region contributing to intelligibility improvement for the enhanced whisper. The spectrum region where the estimated spectrum is larger than twice the size of the clean spectrum is detrimental to speech intelligibility perception within the whisper context. 展开更多
关键词 whispered speech enhancement intelligibilityevaluation real-valued discrete Gabor transform joint time-frequency analysis
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应用2000版ISO9001标准转换测绘质量体系的思路和方法初探 被引量:1
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作者 付殿东 陈之中 丁鹏辉 《测绘通报》 CSCD 北大核心 2001年第9期38-40,43,共4页
阐述了 2 0 0 0版 ISO90 0 1标准的主要变化及特点 ,提出了已获证测绘单位如何做好 2 0 0 0版 ISO90 0 1标准转换的思路和方法 。
关键词 2000版ISO9001标准 测绘质量管理体会 测绘单位 顾客满意度 可评价目标
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引导儿童基于经验建构数学概念——二下《直角的初步认识》一课的教学与反思
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作者 闫颖 《江苏教育》 2022年第57期60-62,共3页
基于经验的课堂最显著的特质就是其生长性。知识的生长主要来自两个方面:一是学生的已有经验,二是知识的结构体系。在“图形与几何”领域,由于受生活经验和已有认知的影响,学生的知识起点并不是零,很多知识在其头脑中已有初步的表象,只... 基于经验的课堂最显著的特质就是其生长性。知识的生长主要来自两个方面:一是学生的已有经验,二是知识的结构体系。在“图形与几何”领域,由于受生活经验和已有认知的影响,学生的知识起点并不是零,很多知识在其头脑中已有初步的表象,只是这些表象是片面的、零散的。在教学中,教师的任务是引导学生完成知识起点与新知之间的关联和改造,从而促进学生真正理解知识、理解数学。另外,教材的编写体现了知识的结构体系,每节课的内容都是结构体系中的一个“节点”。 展开更多
关键词 经验 数学概念 《直角的初步认识》 可评价目标 结构化素材 探究性活动
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STUDY ON MEASURES OF FAULT TOLERANCE FOR DISTRIBUTED SYSTEM
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作者 武小悦 沙基昌 何小怀 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第1期65-68,共4页
Fault tolerant ability is an important aspect for overall evaluation of distributed system(DS). This paper discusses three measures for the evaluation: node/edge connectivity, number of spanning trees and synthetic co... Fault tolerant ability is an important aspect for overall evaluation of distributed system(DS). This paper discusses three measures for the evaluation: node/edge connectivity, number of spanning trees and synthetic connectivity. A numerical example for illustration and analysis is given, and the synthetic connectivity measure presented by this paper is proved to be rational and satisfactory. 展开更多
关键词 distributed network EVALUATIONS fault tole rant technique RELIABILITY network topology distributed system
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Ecosystem health: ecological sustainability target of strategic environment assessment 被引量:1
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作者 陈昆玉 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期146-150,共5页
Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainabili... Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainability target of SEA, the content of ecosystem health as well as the interrelations between SEA and ecosystem health. For a good SEA, its ecological sustainability principles should be provided with distinct content and a general assessment system. A framework for ecosystem health assessment was established according to the content of ecosystem health, and combined into SEA as SEA抯 ecological sustainability target, we can effectively guide decision-makers to make suitable indigenous means and local solutions. , The basic principles and procedure of SEA for ecosystem health are also discussed in the paper. 展开更多
关键词 Environment impact assessment Strategic environmental assessment Ecosystem health
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An evaluation on using soil aggregate stability as the indicator of interrill erodibility 被引量:10
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作者 DING Wen-feng ZHANG Xun-chang 《Journal of Mountain Science》 SCIE CSCD 2016年第5期831-843,共13页
Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate... Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate for estimating interrill types with contrasting and subtropical regions of China. This study was conducted to investigate how closely the soil interrill erodibility factor in the Water Erosion Prediction Project (WEPP) model relates to soil aggregate stability. The mass fractal dimension (FD), geometric mean diameter (GMD), mean weight diameter (MWD), and aggregate stability index (ASI) of soil aggregates were calculated. A rainfall simulator with a drainable flume (3.0 m long × 1.0 m wide × 0.5 m deep) was used at four slope gradients (5°,10 °,15° and 20°), and four rainfall intensities (0.6, 1.1, 1.7 and 2.5 mm/min). Results indicated that the interriU erodibility (Ki) values were significantly correlated to the indices of ASI, MWD, GMD, and FD computed from the aggregate wet-sieve data. The Kihad a strong positive correlation with FD, as well as a strong negative correlation with ASI, GMD, and MWD. Soils with a higher aggregate stability and lower fractal dimension have smaller Ki values. Stable soils were characterized by a high percentage of large aggregates and the erodible soils by a high percentage of smaller aggregates. The correlation coefficients of Ki with ASI and GMD were greater than those with FD and MWD, implying that both the ASI and GMD may be better alternative parameters for empirically predicting the soil Ki factor. ASI and GMD are more reasonable in interrill soil erodibility estimation, compared with Ki calculation in original WEPP model equation. Results demonstrate the validation of soil aggregation characterization as an appropriate indicator of soil susceptibility to erosion in contrasting soil types in China. 展开更多
关键词 Soil erodibility Interrill Aggregate stability Soil erosion
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A VV&A evaluation system based on hierarchical evaluation 被引量:1
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作者 方可 杨明 王子才 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第2期184-188,共5页
Evaluation is the major activity of performing Verification, Validation and Accreditation (VV&A) of a simulation system. Unfortunately, there is a lack of reasonable and operable evaluation methods. Moreover, ther... Evaluation is the major activity of performing Verification, Validation and Accreditation (VV&A) of a simulation system. Unfortunately, there is a lack of reasonable and operable evaluation methods. Moreover, there are other problems to address in VV&A evaluation, such as index definition, conclusion analysis, etc. In this paper, a VV&A evaluation system is introduced to try to resolve these problems. The system is based on a method called hierarchical evaluation, and it uses a good combination of evaluation processes and indexes. First, a thorough analysis of the VV&A evaluation’s essentials and principles are given, then the uncertainty of the evaluation results caused by various analysis of the evaluators is pointed out, then a hierarchical evaluation mechanism based on evaluator weight and evaluation hierarchy is brought forward, and finally a comprehensive VV&A evaluation system with evaluation flow processing, index management and hierarchical evaluation fulfillment is established. The system gives good consideration to ease of operation, reasonableness of evaluation conclusion, and the ability to comprehensively resolve VV&A problems. Since VV&A is attracting more and more recognition, it is meaningful to provide a good system for implementing credible simulation systems. It is hoped that this VV&A evaluation will provide a good way. 展开更多
关键词 VV&A evaluation activity hierarchical evaluation VV&A evaluation system CREDIBILITY
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Research Progress on Evaluation Frameworks of Regional Ecological Sustainability 被引量:9
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作者 PENG Jian WANG Yanglin +2 位作者 WU Jiansheng SHEN Hong PAN Yajing 《Chinese Geographical Science》 SCIE CSCD 2011年第4期496-510,共15页
As natural ecosystems provide the material basis and fundamental support for regional sustainable devel-opment,the sustainability of natural ecosystems is an important prerequisite and a viable approach for the achiev... As natural ecosystems provide the material basis and fundamental support for regional sustainable devel-opment,the sustainability of natural ecosystems is an important prerequisite and a viable approach for the achievement of regional sustainable development.It is also the final criteria to assess whether sustainable development paradigm is successful.Along with the increasing impacts of human activities on natural ecosystems,the evaluation of regional ecological sustainability has become one of the key issues for research on macro ecology and sustainable development.Based on different unit of indicators,this study firstly groups the evaluation frameworks of regional ecological sus-tainability into three major types:comprehensive index evaluation with dimensionless unit,monetary valuation,and biophysical quantity measurement.We then discuss and compare these types in terms of basic principles,scope of ap-plications,advantages and shortcomings.Finally,drawn on the discussion about characteristics of ecological sustain-ability,we outline the current trend and future directions of regional ecological sustainability evaluation,for instance,transition from sustainable development evaluation to sustainability science,integration of goal-oriented and problem-solving approaches,combination of spatial pattern analysis and ecological sustainability evaluation,and en-hancement of ecological sustainability evaluation at landscape scale. 展开更多
关键词 evaluation framework regional ecological sustainability research progress research prospects compre-hensive index evaluation monetary valuation biophysical quantity measurement
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Model of Land Suitability Evaluation Based on Computational Intelligence 被引量:4
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作者 JIAO Limin LIU Yaolin 《Geo-Spatial Information Science》 2007年第2期151-156,共6页
A novel model of land suitability evaluation is built based on computational intelligence (CI). A fuzzy neural network (FNN) is constructed by the integration of fuzzy logic and artificial neural network (ANN). The st... A novel model of land suitability evaluation is built based on computational intelligence (CI). A fuzzy neural network (FNN) is constructed by the integration of fuzzy logic and artificial neural network (ANN). The structure and process of this network is clear. Fuzzy rules (knowledge) are expressed in the model explicitly, and can be self-adjusted by learning from samples. Genetic algorithm (GA) is employed as the learning algorithm to train the network, and makes the training of the model efficient. This model is a self-learning and self-adaptive system with a rule set revised by training. 展开更多
关键词 land suitability evaluation computational intelligence fuzzy neural network genetic algorithm
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Evaluation of Freeway Travel Time Variability and Reliability under Adverse Weather with TRANSMIT Data 被引量:3
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《Journal of Civil Engineering and Architecture》 2012年第1期1-11,共11页
Traffic congestion has caused many detrimental effects including higher fuel consumption, more vehicle emissions, increased accidents, as well as greater tension due to uncertain travel time. In addition to delay, the... Traffic congestion has caused many detrimental effects including higher fuel consumption, more vehicle emissions, increased accidents, as well as greater tension due to uncertain travel time. In addition to delay, the variability and reliability of travel time has been of concern to motorists on their daily travel, especially during peak periods. The objective of this study is to examine freeway travel time variability and reliability under different traffic and weather conditions with the use of TRANSMIT data collected by roadside readers deployed on a 40-mile segment of the Interstate Highway 1-287 in New Jersey. Travel time variability and reliability measures including mean travel time, the 95th percentile travel time, travel time index, buffer index, and planning time index under recurring and non-recurring congestion (adverse weather) are investigated. It was found that the standard deviation of travel time increased, due to the weather condition varying from dry to rain and to snow, while the buffer index increased from 29% to 45% and to 94%. 展开更多
关键词 Travel time VARIABILITY RELIABILITY TRANSMIT ITS traveler information.
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Reliability evaluation method and algorithm for electromechanical product 被引量:2
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作者 刘勇军 范晋伟 李云 《Journal of Central South University》 SCIE EI CAS 2014年第10期3753-3761,共9页
The reliability of electromechanical product is usually determined by the fault number and working time traditionally. The shortcoming of this method is that the product must be in service. To design and enhance the r... The reliability of electromechanical product is usually determined by the fault number and working time traditionally. The shortcoming of this method is that the product must be in service. To design and enhance the reliability of the electromechanical product, the reliability evaluation method must be feasible and correct. Reliability evaluation method and algorithm were proposed. The reliability of product can be calculated by the reliability of subsystems which can be gained by experiment or historical data. The reliability of the machining center was evaluated by the method and algorithm as one example. The calculation result shows that the solution accuracy of mean time between failures is 97.4% calculated by the method proposed in this article compared by the traditional method. The method and algorithm can be used to evaluate the reliability of electromechanical product before it is in service. 展开更多
关键词 reliability evaluation mean time between failures probability density function electromechanical product
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An Assessment of Snow Cover Duration Variability Among Three Basins of Songhua River in Northeast China Using Binary Decision Tree 被引量:1
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作者 YANG Qian SONG Kaishan +2 位作者 HAO Xiaohua CHEN Shengbo ZHU Bingxue 《Chinese Geographical Science》 SCIE CSCD 2018年第6期946-956,共11页
The dynamics of snow cover differs greatly from basin to basin in the Songhua River of Northeast China, which is attributable to the differences in the topographic shift as well as changes in the vegetation and climat... The dynamics of snow cover differs greatly from basin to basin in the Songhua River of Northeast China, which is attributable to the differences in the topographic shift as well as changes in the vegetation and climate since the hydrological year(HY) 2003. Daily and flexible multi-day combinations from the HY 2003 to 2014 were produced using Moderate Resolution Imaging Spectroradiometer(MODIS) from Terra and Aqua remote sensing satellites for the snow cover products in the three basins including the Nenjiang River Basin(NJ), Downstream Songhua River Basin(SD) and Upstream Songhua River Basin(SU). Snow cover duration(SCD) was derived from flexible multiday combination each year. The results showed that SCD was significantly associated with elevation, and higher SCD values were found out in the mountainous areas. Further, the average SCDs of NJ, SU and SD basins were 69.43, 98.14 and 88.84 d with an annual growth of 1.36, 2.04 and 2.71 d, respectively. Binary decision tree was used to analyze the nonlinear relationships between SCD and six impact factors, which were successfully applied to simulate the spatial distribution of depth and water equivalent of snow. The impact factors included three topographic factors(elevation, aspect and slope), two climatic factors(precipitation and air temperature) and one vegetation index(Normalized Difference Vegetation Index, NDVI). By treating yearly SCD values as dependent variables and six climatic factors as independent variables, six binary decision trees were built through the combination classification and regression tree(CART) with and without the consideration of climate effect. The results from the model show that elevation, precipitation and air temperature are the three most influential factors, among which air temperature is the most important and ranks first in two of the three studied basins. It is suggested that SCD in the mountainous areas might be more sensitive to climate warming, since precipitation and air temperature are the major factors controlling the persistence of snow cover in the mountainous areas. 展开更多
关键词 Binary decision tree MODIS snow cover duration topography climate changes
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Optimal transmission lines assignment with maximal reliabilities in multi-source multi-sink multi-state computer network 被引量:1
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作者 章筠 徐正国 +2 位作者 王文海 卢建刚 孙优贤 《Journal of Central South University》 SCIE EI CAS 2013年第7期1868-1877,共10页
The optimal transmission lines assignment with maximal reliabilities (OTLAMR) in the multi-source multi-sink multi-state computer network (MMMCN) was investigated. The OTLAMR problem contains two sub-problems: the MMM... The optimal transmission lines assignment with maximal reliabilities (OTLAMR) in the multi-source multi-sink multi-state computer network (MMMCN) was investigated. The OTLAMR problem contains two sub-problems: the MMMCN reliabilities evaluation and multi-objective transmission lines assignment optimization. First, a reliability evaluation with a transmission line assignment (RETLA) algorithm is proposed to calculate the MMMCN reliabilities under the cost constraint for a certain transmission lines configuration. Second, the non-dominated sorting genetic algorithm II (NSGA-II) is adopted to find the non-dominated set of the transmission lines assignments based on the reliabilities obtained from the RETLA algorithm. By combining the RETLA and the NSGA-II algorithms together, the RETLA-NSGA II algorithm is proposed to solve the OTLAMR problem. The experiments result show that the RETLA-NSGA II algorithm can provide efficient solutions in a reasonable time, from which the decision makers can choose the best solution based on their preferences and experiences. 展开更多
关键词 multi-state network reliability evaluation transmission lines assignments multi-objective optimization non-dominatedsorting genetic algorithm II
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Sustainability Evaluation of Different Systems for Sea Cucumber(Apostichopus japonicus) Farming Based on Emergy Theory 被引量:2
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作者 WANG Guodong DONG Shuanglin +2 位作者 TIAN Xiangli GAO Qinfeng WANG Fang 《Journal of Ocean University of China》 SCIE CAS 2015年第3期503-510,共8页
Emergy analysis is effective for analyzing ecological economic systems. However, the accuracy of the approach is af- fected by the diversity of economic level, meteorological and hydrological parameters in different r... Emergy analysis is effective for analyzing ecological economic systems. However, the accuracy of the approach is af- fected by the diversity of economic level, meteorological and hydrological parameters in different regions. The present study evalu- ated the economic benefits, environmental impact, and sustainability of indoor, semi-intensive and extensive farming systems of sea cucumber (Apostichopus japonicus) in the same region. The results showed that A. japonicus indoor farming system was high in input and output (yield) whereas pond extensive farming system was low in input and output. The output/input ratio of indoor fann- ing system was lower than that of pond extensive farming system, and the output/input ratio of semi-intensive farming system fell in between them. The environmental loading ratio of A.japonicus extensive fanning system was lower than that of indoor farming sys- tem. In addition, the emergy yield and emergy exchange ratios, and emergy sustainability and emergy indexes for sustainable devel- opment were higher in extensive farming system than those in indoor farming system. These results indicated that the current exten- sive farming system exerted fewer negative influences on the environment, made more efficient use of available resources, and met more sustainable development requirements than the indoor farming system. A. japonicus farming systems showed more emergy benefits than fish fanning systems. The pond fanning systems ofA. japonicus exploited more free local environmental resources for production, caused less potential pressure on the local environment, and achieved higher sustainability than indoor farming system. 展开更多
关键词 Apostichopusjaponicas farming systems emergy theory SUSTAINABILITY
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Assessment Index Structure of Mine Ventilation System and Application 被引量:4
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作者 CHENGLei YANGYun-liang XiongYa-xuan 《Journal of China University of Mining and Technology》 EI 2005年第2期135-140,共6页
Based on the basic content of advanced technology,safety and reliability, and economic reasonability and the definition of mine ventilation system, 16 assessment indexes of ventilation system are put forward from the ... Based on the basic content of advanced technology,safety and reliability, and economic reasonability and the definition of mine ventilation system, 16 assessment indexes of ventilation system are put forward from the point of 8 aspects such as mine ventilation power, ventilation network, ventilation equipments, ventilation quality, ventilation monitoring, capacity of preventing and fighting disaster, ventilation consumption of power, and the capacity of ventila- tion system. A new assessment index system is put forward and has a good effect after being applied in coal mines. 展开更多
关键词 ventilation system assessment index system safety and reliability economic reasonability
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Early radiological assessment of locally advanced pancreatic cancer treated with electrochemotherapy 被引量:3
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作者 Vincenza Granata Roberta Fusco +7 位作者 Sergio Venanzio Setola Mauro Piccirillo Maddalena Leongito Raffaele Palaia Francesco Granata Secondo Lastoria Francesco Izzo Antonella Petrillo 《World Journal of Gastroenterology》 SCIE CAS 2017年第26期4767-4778,共12页
To report early imaging assessment of ablated area post electrochemotherapy (ECT) in patients with locally advanced pancreatic cancer (LAPC). METHODSECT was performed in 19 LAPC patients enrolled in an approved ongoin... To report early imaging assessment of ablated area post electrochemotherapy (ECT) in patients with locally advanced pancreatic cancer (LAPC). METHODSECT was performed in 19 LAPC patients enrolled in an approved ongoing clinical phase I/II study. Before and after ECT, 18 patients underwent computed tomography (CT) scan, 11 patients underwent morphological and functional magnetic resonance (MR) scan (dynamic contrast enhanced-MRI) calculating wash-in slope (WIS) and wash-out slope (WOS); diffusion weighted imaging calculating pseudo-diffusivity (Dp), perfusion fraction (fp) and tissue diffusivity (Dt); 10 patients underwent positron emission tomography (PET). Response evaluation criteria in solid tumour (RECIST) on MR and CT were used to assess tumour therapy response. Choi on CT, PET response criteria in solid tumors (PERCIST) on PET and functional parameters on MR were used to evaluate treatment response. RESULTSFor each patient no significant reduction was measurable by CT and MR using RECIST. According Choi criteria a partial response was obtained in 18/18 (100.0%) patients. According PERCIST criteria 6/10 (60.0%) patients showed a partial response, 3/10 (30.0%) stable disease and 1/10 (10.0%) progression disease. Moreover, using functional MR parameters, a significant reduction of viable tumour after ECT can be observed. According ΔWIS and ΔWOS 9/11 (81.8%) patients exhibited a partial response and 2/11 (18.2%) stable disease; 8/11 (72.7%) patients were considered in partial response by ΔDp evaluation and 3/11 (27.3%) in stable disease; according ΔDt 7/11 (63.6%) patients showed a partial response, 1/11 (9.1%) showed progression of disease and 3/11 (27.3%) were stable. Perfusion fraction fp showed a significant reduction after ECT only in four patients. No significant difference was observed after ECT in signal intensity of T1-weighted images and T2-weighted images, and in equilibrium-phase of contrast study, according to χ<sup>2</sup> test was observed. A good correlation was reported between ΔHounsfield unit and Δmaximum standardized uptake value and between Δfp and ΔWOS, with a significant statistically difference (P < 0.05) using Spearman correlation coefficient. CONCLUSIONPerfusion and diffusion MR derived parameters, Choi, PERCIST criteria are more performant than morphological MR and CT criteria to assess ECT treatment response. 展开更多
关键词 Reversible electroporation Response assessment Positron emission tomography/computed tomography Pancreatic cancer Magnetic resonance imaging
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A Service Selection Approach Based on Availability-Aware in Mobile Ad Hoc Networks 被引量:1
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作者 孙其博 王文彬 +1 位作者 邹华 杨放春 《China Communications》 SCIE CSCD 2011年第1期87-94,共8页
Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of ... Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of composite services,this paper first analyzes the node environments and network environments that affect the component services' availability,and then proposes an Environment-aware Quantitative Evaluation Model for Service Availability (EQEM-SA).In addition,based on EQEM-SA,a service field concept is proposed as well as the availability attenuation equation,where the availability value is considered as the field strength.Then the service selection approach based on service field model is presented.The effectiveness of the proposed approach is illustrated and compared with related references,and the results of experimental evaluations indicate that our approach significantly reduces the failure rate and shortens the service delay. 展开更多
关键词 MANETS AVAILABILITY service field service selection
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The evaluation of ecosystem health in mining areas on the matter element method 被引量:2
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作者 LI Xin-ju LIU Xue-ran +2 位作者 LU Yan-yan GUO Shuo-li WANG Mei 《Journal of Coal Science & Engineering(China)》 2011年第2期176-180,共5页
According to the characteristics of ecosystem and concept of the ecosystem in mining area, the index system of the ecosystem health in mining area was set up, and the evaluation standard was established. Aiming at the... According to the characteristics of ecosystem and concept of the ecosystem in mining area, the index system of the ecosystem health in mining area was set up, and the evaluation standard was established. Aiming at the complexion in which the information lost in index ration, the matter element method was put forward to evaluate the ecosystem health in mining area. Making use of the model set up, the weight was built up by the method of index number heavy, the matter element, clas- sical field, and limit field were set up. The rating hierarchy was calculated by relating function. As a case study in the mining area of Pingyangsi Town, the results show that the ecosystem is good and sustainable from 2003 to 2006, but the healthy degree is not high, and some indexes have depravation. 展开更多
关键词 ecosystem health the ecosystem in mining area matter element Pingyangsi Town
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