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The Effects of Fertilizers on Rabbiteye Blueberry(Vaccinium ashei Reade.)Root Distribution and Fruit Yield

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Phyton-International Journal of Experimental Botany 2022年第6期91卷 1289-1302页

作者： Xiaolan Guo Chenyan Liu Muhammad Shakeel Delu Wang College of Forestry Guizhou UniversityGuiyang550025China Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions 9 Institute of EntomologyGuizhou UniversityGuiyang550025China

The root system plays an important role in the growth and development of *** aim of this study was to assess the impacts of different fertilizers on the root growth and root–yield relationship of blueberry to provide insight into the regulation of root growth and fruit yield by fertilizing from the perspective of the root *** blueberry variety‘Britewell’as the test material,and six fertilizers,including BF,OR,CF,SF,HF,and RT were used in single-factor fertilization experiments to analyze the effects of different fertilizer treatments on the root morphology,root distribution,and fruit yield of *** overall increased the root length density and root surface area in most soil layers,and the RT treatment significantly increased the total root length density and total root surface area 98.6%and 98.5%,respectively,compared with a control lacking *** addition,the effect of fertilization on the blueberry root system was mainly observed in the 0–20 cm *** yield was positively correlated with total root length density and total root surface area,and negatively correlated with average root *** summary,the SF and RT treatments increased the morphological indexes of the root system,particularly in the shallow soil layers,leading to an increase in blueberry fruit yield.

关键词： Fertilization membership function root morphology rabbiteye blueberry

Water quality evaluation of Haihe River with fuzzy similarity measure methods

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Journal of Environmental Sciences 2013年第10期25卷 2041-2046页

作者： Xiaojing Wang Zhihong Zou Hui Zou School of Economic and Management Beihang University Department of Applied Mathematics College of ScienceChina Agricultural University

Fuzzy similarity measures, which are used to judge the closeness of two fuzzy sets, are presented to evaluate the water quality of the Haihe River. Based on the membership functions and coefficient of variation as the weights, four fuzzy similarity measures （including Lattice similarity measure, Hamming similarity measure, Euclidean similarity measure and the max-min similarity measure） are used to classify the 299 samples into the proper water quality standard ranks. The results are compared with the traditional distance discriminant methods. The calculation of two traditional distance discriminant methods （both Euclidean distance and absolute value distance） is also based on the use of coefficients of variation as the weights. Without the Lattice similarity measure, for this method loses some information, the correct assignment of samples classified into the same water quality ranks is 75.92% with the other three similarity measures and two distance discriminant methods. This result shows the reliability of the five methods. Only considering the three similarity measures, there were only 1.01% of the samples that did not classify to the same ranks, while the corresponding ratio of the two distance discriminant methods was 5.69%. The results of leave-one-out cross validation show that more than 88% of the samples are classified to the proper ranks, which demonstrates that the similarity measures are suitable to evaluate the water quality of the Haihe River.

关键词： similarity measure distance discriminant coefficient of variation membership function

An adaptive attitude algorithm based on a current statistical model for maneuvering acceleration

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Chinese Journal of Aeronautics 2017年第1期30卷 426-433页

作者： Wang Menglong Wang Hua School of Astronautics Beihang University

A current statistical model for maneuvering acceleration using an adaptive extended Kalman filter（CS-MAEKF） algorithm is proposed to solve problems existing in conventional extended Kalman filters such as large estimation error and divergent tendencies in the presence of continuous maneuvering acceleration. A membership function is introduced in this algorithm to adaptively modify the upper and lower limits of loitering vehicles＇ maneuvering acceleration and for realtime adjustment of maneuvering acceleration variance. This allows the algorithm to have superior static and dynamic performance for loitering vehicles undergoing different maneuvers. Digital simulations and dynamic flight testing show that the yaw angle accuracy of the algorithm is 30% better than conventional algorithms, and pitch and roll angle calculation precision is improved by 60%.The mean square deviation of heading and attitude angle error during dynamic flight is less than3.05°. Experimental results show that CS-MAEKF meets the application requirements of miniature loitering vehicles.

关键词： Attitude and heading reference system Current statistical model Kalman filter Loitering vehicle Maneuvering acceleration membership function

FUZZY MODEL FOR TWO-DIMENSIONAL RIVER WATER QUALITY SIMULATION UNDER SUDDEN POLLUTANTS DISCHARGED

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Journal of Hydrodynamics 2007年第4期19卷 434-441页

作者： LI Ru-zhong SHIGEKI Masunaga HONG Tian-qiu QIAN Jia-zhong School of Resources and Environmental Engineering Hefei University of Technology Hefei 230009 China Graduate School of Environment and Information Sciences Yokohama National University Yokohama 240-8501 Japan

Based on the fuzziness and impreciseness of water environmental system, the fuzzy arithmetic was used to simulate the fuzzy and imprecise relations in modeling river water quality. By defining the parameters of water quality model as symmetrical triangular fuzzy numbers, a two-dimensional fuzzy water quality model for sudden pollutant discharge is established. From the fuzzy model, the pollutant concentrations, corresponding to the specified confidence level of a, can be obtained by means of the a-cut technique and arithmetic operations of triangular fuzzy numbers. Study results reveal that it is feasible in theory and reliable on calculation applying triangular fuzzy numbers to the simulation of river water quality.

关键词： fuzzy water quality simulation model triangular fuzzy number membership function a-cut technique

Optimal operating policy for a controllable queueing model with a fuzzy environment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 311-318页

作者： Chuen-horng LIN Jau-chuan KE Department of Information Management Department of Applied Statistics National Taichung Institute of Technology

We construct the membership functions of the fuzzy objective values of a controllable queueing model,in which cost elements,arrival rate and service rate are all fuzzy numbers. Based on Zadeh's extension principle,a set of parametric nonlinear programs is developed to find the upper and lower bounds of the minimal average total cost per unit time at the possibility level. The membership functions of the minimal average total cost are further constructed using different values of the possibility level. A numerical example is solved successfully to illustrate the validity of the proposed approach. Because the object value is expressed and governed by the membership functions,the optimization problem in a fuzzy environment for the controllable queueing models is represented more accurately and analytical results are more useful for system designers and practitioners.

关键词： Controllable queue Fuzzy sets membership function Nonlinear programming

General Model of Fuzzy Plasticity

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 496-504页

作者： ZHANG Chunliang ZHANG Liangchi School of Mechanical and Electrical Engineering Guangzhou University Guangzhou 510006 China School of Mechanical and Manufacturing Engineering The University of New South Wales Sydney NSW 2052 Australia

The transition between the elastic and plastic states is sharp in the classical plasticity theory. To overcome this problem, many constitutive models, such as multi-yield-surface model and two-surface model, have been developed. However, these models can not represent the true deformation process in a material. In order to capture nonlinear hardening behavior and smooth transition from elastic to plastic state, a general model of fuzzy plasticity is developed. On the basis of the theory of fuzzy sets and TAKAGI-SUGENO fuzzy model, a fuzzy plastic model for monotonic and cyclic loadings in one dimension is established and it is generalized to six dimensions and unsymmetric cycles. The proposed model uses a set of surfaces to partition the stress space with individual plastic modulus. The plastic modulus between two adjacent surfaces is determined by a membership function. By means of a finite number of partitioning surfaces, the fuzzy plastic model can provide with a more realistic and practical description of the materials behavior than the classical plasticity model. The validity of the fuzzy plastic model is investigated by comparing the predicted and experimental stress-strain responses of steels. It was found that the fuzzy plasticity has the ability to handle many practical problems that cannot be adequately analyzed by the conventional theory of plasticity.

关键词： plasticity theory fuzzy model membership function plastic modulus stress-strain curve

A novel context-aware RPL algorithm based on a triangle module operator

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Frontiers of Information Technology & Electronic Engineering 2021年第12期22卷 1583-1597页

作者： Yanan CAO Hao YUAN Tianjin Key Laboratory of Wireless Mobile Communications and Power Transmission Tianjin Normal UniversityTianjin 300387China Chinese People's Liberation Army Unit 61846 Zhuozhou 072750China

For the use in low-power and lossy networks(LLNs)under complex and harsh communication conditions,the routing protocol for LLNs(RPL)standardized by the Internet Engineering Task Force is specially *** improve the performance of LLNs,we propose a novel context-aware RPL algorithm based on a triangle module operator(CAR-TMO).A novel composite context-aware routing metric(CA-RM)is designed,which synchronously evaluates the residual energy index,buffer occupancy ratio of a node,expected transmission count(ETX),delay,and hop count from a candidate parent to the ***-RM considers the residual energy index and buffer occupancy ratio of the candidate parent and its preferred parent in a recursive manner to reduce the effect of upstream parents,since farther paths are ***-RM comprehensively uses the sum,mean,and standard deviation values of ETX and delay of links in a path to ensure a better ***,in CAR-TMO,the membership function of each routing metric is ***,a comprehensive membership function is constructed based on a triangle module operator,the membership function of each routing metric,and a comprehensive context-aware objective function.A novel mechanism for calculating the node rank and the mechanisms for preferred parent selection are ***,theoretical analysis and simulation results show that CAR-TMO outperforms several state-of-the-art RPL algorithms in terms of the packet delivery ratio and energy efficiency.

关键词： Triangle module operator membership function Context-aware Routing protocol for low-power and lossy networks(RPL) Routing metrics

BEST WEIGHT PATTERN EVALUATION BASED SECURITY CONSTRAINED POWER DISPATCH ALGORITHM

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Journal of Systems Science and Systems Engineering 2007年第3期16卷 287-307页

作者： Lakhwinder SINGH J.S. DHILLON Baba Banda Singh Bahadur Engineering College Fatehgarh Sahib- 140407 Punjab India Sant Longowal Institute of Engineering & Technology Longowa1-148 106 Punjab India

This paper presents a methodology which determines the allocation of power demand among the committed generating units while minimizes number of objectives as well as meets physical and technological system constraints. The procedure considers two decoupled problems based upon the dependency of their goals on either active power or reactive power generation. Both the problems have been solved sequentially to achieve optimal allocation of active and reactive power generation while minimizes operating cost, gaseous pollutants emission objectives and active power transmission loss with consideration of system operating constraints along with generators prohibited operating zones and transmission line flow limits. The active and reactive power line flows are obtained with the help of generalized generation shift distribution factors （GGDF） and generalized Z-bus distribution factors （GZBDF）, respectively. First problem is solved in multi-objective framework in which the best weights assigned to objectives are determined while employing weighting method and in second problem, active power loss of the system is minimized subject to system constraints. The validity of the proposed method is demonstrated on 30-bus IEEE power system.

关键词： Multi-objective optimization best weight pattern evaluation fuzzy decision making membership function generalized generation shift distribution factors generalised Z-bus distribution factors

Automated Detection of Contaminated Radar Image Pixels in Mountain Areas

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Advances in Atmospheric Sciences 2008年第5期25卷 778-790页

作者：刘黎平 QinXU PengfeiZHANG ShunLIU State Key laboratory of Severe weather Chinese Academy of Meteorological Sciences Beijing 100081 NOAA/National Severe Stolons Laboratory Nonnan Oklahoma CIMMS University of Oklahoma Norman Oklahoma

In mountain areas, radar observations are often contaminated （1） by echoes from high-speed moving vehicles and （2） by point-wise ground clutter under either normal propagation （NP） or anomalous propagation （AP） conditions. Level Ⅱ data are collected from KMTX （Salt Lake City, Utah） radar to analyze these two types of contamination in the mountain area around the Great Salt Lake. Human experts provide the ＂ground truth＂ for possible contamination of either type on each individual pixel. Common features are then extracted for contaminated pixels of each type. For example, pixels contaminated by echoes from high-speed moving vehicles are characterized by large radial velocity and spectrum width. Echoes from a moving train tend to have larger velocity and reflectivity but smaller spectrum width than those from moving vehicles on highways. These contaminated pixels are only seen in areas of large terrain gradient （in the radial direction along the radar beam）. The same is true for the second type of contamination - pointwise ground clutters. Six quality control （QC） parameters are selected to quantify the extracted features. Histograms are computed for each QC parameter and grouped for contaminated pixels of each type and also for non-contaminated pixels. Based on the computed histograms, a fuzzy logical algorithm is developed for automated detection of contaminated pixels. The algorithm is tested with KMTX radar data under different （clear and rainy） weather conditions.

关键词： radar data quality control membership function point-wise ground clutter moving vehicle echoes