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Post-processing Free Quantum Random Number Generator Based on Avalanche Photodiode Array 被引量:2
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作者 李杨 廖胜凯 +3 位作者 梁福田 沈奇 梁昊 彭承志 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期9-11,共3页
Quantum random number generators adopting single negligible dead time of avalanche photodiodes (APDs) photon detection have been restricted due to the non- We propose a new approach based on an APD array to improve... Quantum random number generators adopting single negligible dead time of avalanche photodiodes (APDs) photon detection have been restricted due to the non- We propose a new approach based on an APD array to improve the generation rate of random numbers significantly. This method compares the detectors' responses to consecutive optical pulses and generates the random sequence. We implement a demonstration experiment to show its simplicity, compactness and scalability. The generated numbers are proved to be unbiased, post-processing free, ready to use, and their randomness is verified by using the national institute of standard technology statistical test suite. The random bit generation efficiency is as high as 32.8% and the potential generation rate adopting the 32× 32 APD array is up to tens of Gbits/s. 展开更多
关键词 of in it APD post-processing Free Quantum Random Number Generator Based on Avalanche Photodiode Array IS on for been that
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Pre-processing and post-processing method for geostress simulation using seismic interpretation results 被引量:1
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作者 ZHANG Li-hong 《Mining Science and Technology》 EI CAS 2009年第3期369-372,共4页
In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflec... In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflect actual situations and facilitate their computation and analyses.Given the importance of model building, further processing methods about traditional seismic interpretation results from Landmark should be studied and the processed result can then be directly used in numerical simulation computations.Through this data conversion procedure, Landmark and FLAC(the international general stress software) are seamlessly connected.Thus, the format conversion between the two systems and the pre-and post-processing in simulation computation is realized.A practical application indicates that this method has many advantages such as simple operation, high accuracy of the element subdivision and high speed, which may definitely satisfy the actual needs of floor grid cutting. 展开更多
关键词 seismic interpretation numerical simulation PRE-PROCESSING post-processing COUPLING
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Development of a Post-Processing Automation Procedure for the GPS-Based Travel Time Data Collection Technique 被引量:2
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作者 Laura Berzina Ardeshir Faghri +1 位作者 Morteza Tabatabaie Shourijeh Mingxin Li 《Journal of Transportation Technologies》 2014年第1期63-71,共9页
The travel time data collection method is used to assist the congestion management. The use of traditional sensors (e.g. inductive loops, AVI sensors) or more recent Bluetooth sensors installed on major roads for coll... The travel time data collection method is used to assist the congestion management. The use of traditional sensors (e.g. inductive loops, AVI sensors) or more recent Bluetooth sensors installed on major roads for collecting data is not sufficient because of their limited coverage and expensive costs for installation and maintenance. Application of the Global Positioning Systems (GPS) in travel time and delay data collections is proven to be efficient in terms of accuracy, level of details for the data and required data collection of man-power. While data collection automation is improved by the GPS technique, human errors can easily find their way through the post-processing phase, and therefore data post-processing remains a challenge especially in case of big projects with high amount of data. This paper introduces a stand-alone post-processing tool called GPS Calculator, which provides an easy-to-use environment to carry out data post-processing. This is a Visual Basic application that processes the data files obtained in the field and integrates them into Geographic Information Systems (GIS) for analysis and representation. The results show that this tool obtains similar results to the currently used data post-processing method, reduces the post-processing effort, and also eliminates the need for the second person during the data collection. 展开更多
关键词 Global POSITIONING Systems (GPS) post-processing Tool VBA GIS KALMAN Filter
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A study on fast post-processing massive data of casting numerical simulation on personal computers 被引量:1
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作者 Chen Tao Liao Dunming +1 位作者 Pang Shenyong Zhou Jianxin 《China Foundry》 SCIE CAS 2013年第5期321-324,共4页
When castings become complicated and the demands for precision of numerical simulation become higher,the numerical data of casting numerical simulation become more massive.On a general personal computer,these massive ... When castings become complicated and the demands for precision of numerical simulation become higher,the numerical data of casting numerical simulation become more massive.On a general personal computer,these massive numerical data may probably exceed the capacity of available memory,resulting in failure of rendering.Based on the out-of-core technique,this paper proposes a method to effectively utilize external storage and reduce memory usage dramatically,so as to solve the problem of insufficient memory for massive data rendering on general personal computers.Based on this method,a new postprocessor is developed.It is capable to illustrate filling and solidification processes of casting,as well as thermal stess.The new post-processor also provides fast interaction to simulation results.Theoretical analysis as well as several practical examples prove that the memory usage and loading time of the post-processor are independent of the size of the relevant files,but the proportion of the number of cells on surface.Meanwhile,the speed of rendering and fetching of value from the mouse is appreciable,and the demands of real-time and interaction are satisfied. 展开更多
关键词 casting numerical simulation massive data fast post-processing
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A method of line spectrum extraction based on target radiated spectrum feature and its post-processing 被引量:1
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作者 DAI Wenshu ZHENG Enming BAO Kaikai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第6期1381-1393,共13页
To improve the ability of detecting underwater targets under strong wideband interference environment,an efficient method of line spectrum extraction is proposed,which fully utilizes the feature of the target spectrum... To improve the ability of detecting underwater targets under strong wideband interference environment,an efficient method of line spectrum extraction is proposed,which fully utilizes the feature of the target spectrum that the high intense and stable line spectrum is superimposed on the wide continuous spectrum.This method modifies the traditional beam forming algorithm by calculating and fusing the beam forming results at multi-frequency band and multi-azimuth interval,showing an excellent way to extract the line spectrum when the interference and the target are not in the same azimuth interval simultaneously.Statistical efficiency of the estimated azimuth variance and corresponding power of the line spectrum band depends on the line spectra ratio(LSR)of the line spectrum.The change laws of the output signal to noise ratio(SNR)with the LSR,the input SNR,the integration time and the filtering bandwidth of different algorithms bring the selection principle of the critical LSR.As the basis,the detection gain of wideband energy integration and the narrowband line spectrum algorithm are theoretically analyzed.The simulation detection gain demonstrates a good match with the theoretical model.The application conditions of all methods are verified by the receiver operating characteristic(ROC)curve and experimental data from Qiandao Lake.In fact,combining the two methods for target detection reduces the missed detection rate.The proposed post-processing method in2-dimension with the Kalman filter in the time dimension and the background equalization algorithm in the azimuth dimension makes use of the strong correlation between adjacent frames,could further remove background fluctuation and improve the display effect. 展开更多
关键词 towed linear array sonar target radiated noise spectrum line spectra level ratio(LSR) receiver operating characteristic(ROC)curve post-processing
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Improved Sinusoid Analysis and Post-Processing in Parametric Audio Coding
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作者 周宏 陈健 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期163-168,共6页
This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids... This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids. The sinusoid which contributes most to the reduction of overall NMR is chosen. Combined with our improved parametric psychoacoustic model and advanced peak riddling techniques, the number of sinusoids required can be greatly reduced and the coding efficiency can be greatly enhanced. A lightweight version is also given to reduce the amount of computation with only little sacrifice of performance. Secondly, we propose two enhancement techniques for sinusoid synthesis: bandwidth enhancement and line enhancement. With little overhead, the effective bandwidth can be extended one more octave; the timbre tends to sound much brighter, thicker and more beautiful. 展开更多
关键词 parametric audio coding SINUSOID post-processing
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A Post-Processing Algorithm for Boosting Contrast of MRI Images
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作者 B.Priestly Shan O.Jeba Shiney +3 位作者 Sharzeel Saleem V.Rajinikanth Atef Zaguia Dilbag Singh 《Computers, Materials & Continua》 SCIE EI 2022年第8期2749-2763,共15页
Low contrast of Magnetic Resonance(MR)images limits the visibility of subtle structures and adversely affects the outcome of both subjective and automated diagnosis.State-of-the-art contrast boosting techniques intole... Low contrast of Magnetic Resonance(MR)images limits the visibility of subtle structures and adversely affects the outcome of both subjective and automated diagnosis.State-of-the-art contrast boosting techniques intolerably alter inherent features of MR images.Drastic changes in brightness features,induced by post-processing are not appreciated in medical imaging as the grey level values have certain diagnostic meanings.To overcome these issues this paper proposes an algorithm that enhance the contrast of MR images while preserving the underlying features as well.This method termed as Power-law and Logarithmic Modification-based Histogram Equalization(PLMHE)partitions the histogram of the image into two sub histograms after a power-law transformation and a log compression.After a modification intended for improving the dispersion of the sub-histograms and subsequent normalization,cumulative histograms are computed.Enhanced grey level values are computed from the resultant cumulative histograms.The performance of the PLMHE algorithm is comparedwith traditional histogram equalization based algorithms and it has been observed from the results that PLMHE can boost the image contrast without causing dynamic range compression,a significant change in mean brightness,and contrast-overshoot. 展开更多
关键词 Contrast enhancement histogram equalisation image quality magnetic resonance imaging medical image analysis post-processing
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Hybrid Post-Processing Procedure for Displacement-Based Plane Elements
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作者 Xiaoming Chen Song Cen +1 位作者 Jianyun Sun Yungui Li 《Journal of Applied Mathematics and Physics》 2013年第6期15-19,共5页
In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produce... In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produced by wall holes and the loss of precision induced by using differential method to derive strains, the displacement-based elements cannot always present accuracy enough for design. In this paper, the hybrid post-processing procedure based on the Hellinger-Reissner variational principle is used for improving the stress precision of two quadrilateral plane elements. In order to find the best stress field, three different forms are assumed for the displacement-based plane elements and with drilling DOF. Numerical results show that by using the proposed method, the accuracy of stress solutions of these two displacement-based plane elements can be improved. 展开更多
关键词 FINITE ELEMENT Displacement-Based PLANE ELEMENT HYBRID post-processing PROCEDURE
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PHP中Private修饰符与Constructor
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作者 温振宏 《数字技术与应用》 2016年第6期181-181,共1页
在PHP程序设计语言中,public,protected,private是面向对象的三种访问控制修饰符。其中,修饰符private修饰的类中成员属性或方法的访问限制最严格,只能在该类的内部访问。本文详细地分析了private修饰符及构造器constructor的应用。
关键词 PHP PRIVATE constructor
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Abstraction from Constructors and Functional Constructors and Their Applications
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作者 Kazuhiko Kakehi 1, Robert Gluck 2, Yoshihiko Futamura 3 1 JSPS Research Fellow Graduate School of Science and Engineering, Waseda University,Tokyo 169 8555, Japan 2 PRESTO, JST & Institute for Software Production Technology, Waseda Universi 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期368-374,共7页
Structures using constructors are of ordinary use in functional programming to represent data structures of unbound size. Lack of associativity of constructors, however, hinders program analyses or efficient execution... Structures using constructors are of ordinary use in functional programming to represent data structures of unbound size. Lack of associativity of constructors, however, hinders program analyses or efficient executions. This paper describes ideas of abstraction toward constructors, and similarly abstraction from constructing functions, which we call functional constructors. We demonstrate our ideas making program analyses easier and enable transformation to efficient execution. 展开更多
关键词 program transformation lambda abstraction constructorS recursion removal tupling
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Clinical Analysis of GPT Alteration of Constructors for Qinghai-Tibetan Railroad at Different Altitude Areas
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作者 Peng Quansheng Yuan Zhengcai +5 位作者 Wang Zhengjiang Wu Zhiling Zhang Xinxia Ge Rili Jin Guoen Hu Ying 《工程科学(英文版)》 2006年第2期227-230,共4页
Objective: To observe the effect of hypoxia on the liver function of constructors at high altitude. Method: Select 221 constructors aged 23~42 as subjects, who had worked for 3~6 months at 4500 m. Collect venous blo... Objective: To observe the effect of hypoxia on the liver function of constructors at high altitude. Method: Select 221 constructors aged 23~42 as subjects, who had worked for 3~6 months at 4500 m. Collect venous blood from fasting subjects and determine GPT by new Lai’s Method from “The Nationwide Clinical Inspection Operating Rules". Results: The study indicated that the GPT of 45 subjects among Group 1 were abnormal, with the proportion of 20.3%. The peak of GPT appeared when subjects exposed to high altitude of 4500m for 1 month, and the mean value was 83.76±9.23.The GPT of workers were higher than that of administers at different altitude (p<0.05). And the GPT of subjects at 4500 m were higher than those at 3500 m (p<0.05). We can find a degrading tendency with the increasing of working time (p<0.05). There was significantly statistic difference between two groups. Conclusions: The study confirmed that hypoxia could cause the change of liver function mildly and moderately. And there was a positive correlation between the degree of hypoxia and liver function. But, the change began to become a decreasing trend when people went on working longer. We also found that the change of liver structure and function at high altitude correlated with several factors else, including labor, individual difference, methods and sensitivity to the test. However, the explanation of its key mechanism deserves further investigation. 展开更多
关键词 青藏铁路 施工人员 肝功能 缺氧 临床分析 职业健康
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复杂系统视角下洞室施工人员安全认知仿真研究
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作者 江新 张腾飞 +3 位作者 陈婧 赵力 邱国坤 王辉 《中国安全科学学报》 CAS CSCD 北大核心 2024年第2期22-30,共9页
为制定有效的安全认知提升策略及减少安全事故的发生,需深入探究洞室施工人员安全认知的演化过程和特征。首先,基于复杂社会技术系统和“2-4”模型(24Model)等相关知识,识别安全认知影响因素,构建洞室施工人员安全认知指标体系;然后,通... 为制定有效的安全认知提升策略及减少安全事故的发生,需深入探究洞室施工人员安全认知的演化过程和特征。首先,基于复杂社会技术系统和“2-4”模型(24Model)等相关知识,识别安全认知影响因素,构建洞室施工人员安全认知指标体系;然后,通过Super Decisions软件计算指标权重;随后利用系统动力学(SD)理论,明确各因素间的相互关系,建立包含组织安全管理等4个子系统的SD仿真模型,将以安全投入为基础的认知纠偏机制应用到SD仿真模型;最后,结合实际工程算例开展SD仿真以及敏感性分析。研究表明:随着工程进展,通过增加安全投入,并发挥认知纠偏机制作用,施工人员的整体安全认知由下降趋势转变为缓慢上升趋势;组织安全管理对洞室施工人员安全认知影响程度最大,结果与24Model的基本假设一致,从而验证了SD仿真模型的科学性和有效性。 展开更多
关键词 复杂系统 洞室施工人员 安全认知 “2-4”模型(24Model) 系统动力学(SD)
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Non-crossing Quantile Regression Neural Network as a Calibration Tool for Ensemble Weather Forecasts 被引量:1
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作者 Mengmeng SONG Dazhi YANG +7 位作者 Sebastian LERCH Xiang'ao XIA Gokhan Mert YAGLI Jamie M.BRIGHT Yanbo SHEN Bai LIU Xingli LIU Martin Janos MAYER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1417-1437,共21页
Despite the maturity of ensemble numerical weather prediction(NWP),the resulting forecasts are still,more often than not,under-dispersed.As such,forecast calibration tools have become popular.Among those tools,quantil... Despite the maturity of ensemble numerical weather prediction(NWP),the resulting forecasts are still,more often than not,under-dispersed.As such,forecast calibration tools have become popular.Among those tools,quantile regression(QR)is highly competitive in terms of both flexibility and predictive performance.Nevertheless,a long-standing problem of QR is quantile crossing,which greatly limits the interpretability of QR-calibrated forecasts.On this point,this study proposes a non-crossing quantile regression neural network(NCQRNN),for calibrating ensemble NWP forecasts into a set of reliable quantile forecasts without crossing.The overarching design principle of NCQRNN is to add on top of the conventional QRNN structure another hidden layer,which imposes a non-decreasing mapping between the combined output from nodes of the last hidden layer to the nodes of the output layer,through a triangular weight matrix with positive entries.The empirical part of the work considers a solar irradiance case study,in which four years of ensemble irradiance forecasts at seven locations,issued by the European Centre for Medium-Range Weather Forecasts,are calibrated via NCQRNN,as well as via an eclectic mix of benchmarking models,ranging from the naïve climatology to the state-of-the-art deep-learning and other non-crossing models.Formal and stringent forecast verification suggests that the forecasts post-processed via NCQRNN attain the maximum sharpness subject to calibration,amongst all competitors.Furthermore,the proposed conception to resolve quantile crossing is remarkably simple yet general,and thus has broad applicability as it can be integrated with many shallow-and deep-learning-based neural networks. 展开更多
关键词 ensemble weather forecasting forecast calibration non-crossing quantile regression neural network CORP reliability diagram post-processing
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Post processing of additive manufactured Mg alloys:Current status,challenges,and opportunities
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作者 Nooruddin Ansari Fatima Ghassan Alabtah +1 位作者 Mohammad I.Albakri Marwan Khraisheh 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1283-1310,共28页
Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the med... Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to bone.The ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflecting a transformation in the manufacturing sectors.However,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification temperature.This leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg alloys.To address these issues,post-processing of AM Mg alloys are often needed to make them suitable for application.The present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface peening.The utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also discussed.Optimal post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are detailed.Additionally,future prospects and research directions are proposed. 展开更多
关键词 Magnesium alloy Additive manufacturing post-processing Heat treatment HIP
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THAPE: A Tunable Hybrid Associative Predictive Engine Approach for Enhancing Rule Interpretability in Association Rule Learning for the Retail Sector
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作者 Monerah Alawadh Ahmed Barnawi 《Computers, Materials & Continua》 SCIE EI 2024年第6期4995-5015,共21页
Association rule learning(ARL)is a widely used technique for discovering relationships within datasets.However,it often generates excessive irrelevant or ambiguous rules.Therefore,post-processing is crucial not only f... Association rule learning(ARL)is a widely used technique for discovering relationships within datasets.However,it often generates excessive irrelevant or ambiguous rules.Therefore,post-processing is crucial not only for removing irrelevant or redundant rules but also for uncovering hidden associations that impact other factors.Recently,several post-processing methods have been proposed,each with its own strengths and weaknesses.In this paper,we propose THAPE(Tunable Hybrid Associative Predictive Engine),which combines descriptive and predictive techniques.By leveraging both techniques,our aim is to enhance the quality of analyzing generated rules.This includes removing irrelevant or redundant rules,uncovering interesting and useful rules,exploring hidden association rules that may affect other factors,and providing backtracking ability for a given product.The proposed approach offers a tailored method that suits specific goals for retailers,enabling them to gain a better understanding of customer behavior based on factual transactions in the target market.We applied THAPE to a real dataset as a case study in this paper to demonstrate its effectiveness.Through this application,we successfully mined a concise set of highly interesting and useful association rules.Out of the 11,265 rules generated,we identified 125 rules that are particularly relevant to the business context.These identified rules significantly improve the interpretability and usefulness of association rules for decision-making purposes. 展开更多
关键词 Association rule learning post-processing PREDICTIVE machine learning rule interpretability
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地方院校园林专业区域化执业人才培养机制
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作者 黄新 赵文慧 李永民 《武夷学院学报》 2024年第3期91-95,共5页
地方院校园林专业要摆脱单纯照搬名校教育框架的束缚,就必须探索区域化特色办学道路,健全区域培养机制。皖北F校凭借丰富的教育实践,首创了“四位一体”的区域人才综合培养机制:工程贴身服务、科教融汇协作、产教联动培养、区域就业引... 地方院校园林专业要摆脱单纯照搬名校教育框架的束缚,就必须探索区域化特色办学道路,健全区域培养机制。皖北F校凭借丰富的教育实践,首创了“四位一体”的区域人才综合培养机制:工程贴身服务、科教融汇协作、产教联动培养、区域就业引导。实践证明,这种创新的培养方式有效地大幅提升了毕业生适应长三角工程市场的能力,为区域“美丽大蓝图”培养了众多致力于区域园林事业的新一代高素质专业人才。 展开更多
关键词 园林专业 区域化 执业建设者 人才培养机制 地方高校
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Line Patterns Segmentation in Blurred Images Using Contrast Enhancement and Local Entropy Thresholding
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作者 Marios Vlachos Evangelos Dermatas 《Journal of Computer and Communications》 2024年第2期116-141,共26页
Finger vein extraction and recognition hold significance in various applications due to the unique and reliable nature of finger vein patterns. While recently finger vein recognition has gained popularity, there are s... Finger vein extraction and recognition hold significance in various applications due to the unique and reliable nature of finger vein patterns. While recently finger vein recognition has gained popularity, there are still challenges associated with extracting and processing finger vein patterns related to image quality, positioning and alignment, skin conditions, security concerns and processing techniques applied. In this paper, a method for robust segmentation of line patterns in strongly blurred images is presented and evaluated in vessel network extraction from infrared images of human fingers. In a four-step process: local normalization of brightness, image enhancement, segmentation and cleaning were involved. A novel image enhancement method was used to re-establish the line patterns from the brightness sum of the independent close-form solutions of the adopted optimization criterion derived in small windows. In the proposed method, the computational resources were reduced significantly compared to the solution derived when the whole image was processed. In the enhanced image, where the concave structures have been sufficiently emphasized, accurate detection of line patterns was obtained by local entropy thresholding. Typical segmentation errors appearing in the binary image were removed using morphological dilation with a line structuring element and morphological filtering with a majority filter to eliminate isolated blobs. The proposed method performs accurate detection of the vessel network in human finger infrared images, as the experimental results show, applied both in real and artificial images and can readily be applied in many image enhancement and segmentation applications. 展开更多
关键词 Finger Vein Vessel Enhancement Vessel Network Extraction Non-Uniform Images BINARIZATION Morphological post-processing
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局部倾角约束最小二乘偏移方法研究 被引量:29
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作者 刘玉金 李振春 +2 位作者 吴丹 黄建平 魏小强 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2013年第3期1003-1011,共9页
随着石油勘探难度的进一步加大,地震数据往往存在采样不规则、地震道缺失等现象,如果不对其进行处理,会对后续的地震成像产生影响,引入成像噪音.针对这一问题,一般是通过地震道插值或数据规则化对叠前数据进行处理,然后采用常规的偏移... 随着石油勘探难度的进一步加大,地震数据往往存在采样不规则、地震道缺失等现象,如果不对其进行处理,会对后续的地震成像产生影响,引入成像噪音.针对这一问题,一般是通过地震道插值或数据规则化对叠前数据进行处理,然后采用常规的偏移方法进行成像,本文则是将地震成像看作最小二乘反演问题,在共成像点道集引入平滑算子,在共偏移距/角度道集引入平面波构造算子(PWC)进行约束,通过预条件共轭梯度法使得反偏移后数据与输入数据之间的误差达到最小,最终得到信噪比更高、振幅属性更为可靠的成像结果.理论模型和实际资料处理表明,本文方法不仅可以有效压制数据不规则对成像产生的噪音,而且具有更高的成像精度. 展开更多
关键词 最小二乘偏移 局部倾角 平面波构造滤波器 不规则数据 高信噪比
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开放课程的探索与思考——从学习者、决策者到建设者 被引量:39
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作者 任友群 徐世猛 《现代远程教育研究》 CSSCI 2013年第5期3-10,共8页
近年来,开放课程越来越受到互联网时代学习者的追捧,越来越多的人体验在网上自由选择心仪的开放课程并满怀期待地享受全新的学习形式。斯坦福大学课程开放的历史悠久,通过"斯坦福在线"提供课程开放服务,在提供优质教育体验方... 近年来,开放课程越来越受到互联网时代学习者的追捧,越来越多的人体验在网上自由选择心仪的开放课程并满怀期待地享受全新的学习形式。斯坦福大学课程开放的历史悠久,通过"斯坦福在线"提供课程开放服务,在提供优质教育体验方面保持领先地位。研究者通过体验和探讨斯坦福大学的开放课程,从"学习者"、"决策者"和"建设者"三个视角分析开放课程运动的经验,试图探索开放课程运动发展的基本规律:从"学习者"角度对开放课程需要解决学习动机、学习孤独感和在线学习能否成为主流学习形式的顾虑问题,这不仅涉及增强在线学习信心,更涉及到信息化时代在线学习的地位和发展。从大学"决策者"角度首先应确定开放课程的价值在于推进课程资源共建共享的共识,这个共识孕育了一场知识价值观的深刻变革。全球近200所高等教育机构投身开放教育大潮,正是对开放课程运动精神的肯定,并形成诸如培养学习者数字化学习能力、大规模开放在线课程(MOOC)通过学分制与传统教育接轨等经验。因此,从"建设者"角度来说,在项目规划阶段,就应考虑项目所涉及的技术障碍、队伍建设和平台建设等方面问题。尽管目前开放课程运动的发展方向仍具有不确定性,中国的一流大学也应该参与其中,甚至创建中国的MOOC平台。 展开更多
关键词 开放课程运动 斯坦福在线 学习者 决策者 建设者 MOOC平台
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中英建造师执业资格制度对比研究 被引量:8
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作者 洪红 朱雅彬 +1 位作者 廖奇云 潘晓丽 《重庆建筑大学学报》 CSCD 2003年第5期101-107,共7页
在我国,建造师执业资格制度是对于从事建筑活动的专业技术人员设立的一个全新的执业资格制度。本文介绍了我国设立建造师执业资格制度的背景、必要性和目的以及国际上在此领域的发展情况;论述了我国和英国的建造师执业资格制度各自的特... 在我国,建造师执业资格制度是对于从事建筑活动的专业技术人员设立的一个全新的执业资格制度。本文介绍了我国设立建造师执业资格制度的背景、必要性和目的以及国际上在此领域的发展情况;论述了我国和英国的建造师执业资格制度各自的特点;通过对两者的差异进行对比研究,阐明了目前我国建造师执业资格制度的欠缺和待改进之处,进而对该执业资格体系在今后的发展、完善等有关方面提出了建议。 展开更多
关键词 建造师 执业资格制度 执业资格管理 工程项目管理
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