期刊文献+
共找到6,674篇文章
< 1 2 250 >
每页显示 20 50 100
A Loss-model-based Efficiency Optimization Control Method for Induction Traction System of High-speed Train under Emergency Self-propelled Mode
1
作者 Yutong Zhu Yaohua Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期227-239,共13页
Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link v... Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results. 展开更多
关键词 efficiency optimization Induction motor Loss model control Motor drives Traction system
下载PDF
Effect of Slow and Controlled Release Fertilizers on the Yield and Nutrient Use Efficiency of Hot Pepper in Qiu-bei 被引量:8
2
作者 杜彩艳 段宗颜 +2 位作者 鲁耀 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第5期761-764,共4页
[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei ho... [Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper(Capsicum frutescens L.)as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection. 展开更多
关键词 Slow and controlled release fertilizer Qiubei hot pepper YIELD Nutrient use efficiency
下载PDF
On the Bacteriostatic Activity of Bacillus subtilis and Pyraclostrobin as Well as Their Mixtures to Grape Anthracnose and the Field Disease Control Efficiency 被引量:2
3
作者 吉沐祥 毛妮妮 +6 位作者 李国平 姚克兵 刘吉祥 陈宏州 吴祥 郭建 芮东明 《Agricultural Science & Technology》 CAS 2015年第12期2736-2741,共6页
[Objective] To screen out the biological compound bactericides for grape anthracnose, reduce and replace the use of chemical pesticide. [Methods] The de- termination on the indoor bacteriostatic activity of different ... [Objective] To screen out the biological compound bactericides for grape anthracnose, reduce and replace the use of chemical pesticide. [Methods] The de- termination on the indoor bacteriostatic activity of different proportions of Bacillus subtilis and pyraclostrobin to grape anthracnose was carried out, and mycelial growth rate method was adopted to determine the toxicity of Bacillus subtilis and pyraclostrobin as well as their 5 mixtures to grape anthracnose. [Results] The EC50 of Bacillus subtilis and pyraclostrobin as well as their mixture combinations of 1:1, 1:2, 1:3, 1:4 and 1:5 to grape anthracnose were respectively 1.969 8, 1.527 4, 1.373 2, 1.294 8 and 1.247 3 μg/ml; the synergistic coefficients (SR) of the 5 mix- ture combinations to grape anthracnose were 1.70, 1.25, 1.13, 1.12 and 1.12, re- spectively, in which the synergistic effect of 1:1 was the largest. The indoor biologi- cal activity of pyraclostrobin(EC50 was 1.054 0μg/ml) was higher than that of Bacil- lus subtilis(EC50 was 15.017 5 μg/ml). 50 d after the agentia(before the harvesting), the investigation results showed that 1 000-fold dilution, 1 500-fold dilution and 2 000- fold dilution as well as each single dosage of 20% pyraclostrobin .200×10^8 cfu/g Bacillus subtili wettable powder all had better control efficiency to grape anthracnose after fruit setting and before bagging, in which the treatments of high concentration and middle concentration were higher than the treatments of low concentration and two single dosages: the highest control efficiency of high concentration was 90.03%, which was higher than all other treatments; the control efficiency of middle concen- tration was 87.01%, which was higher than that of low concentration and each sin- gle dosage; the control efficiency of low concentration was 84.11%, which was high- er than 1 000-fold dilution of 1 000×10^8 cfu/g Bacillus subti/i wettable powder (the control efficiency was 64.60%) and 2 000-fold dilution of 250 g/L Bacillus subti/i wettable powder (the control efficiency was 81.07%). In addition, each treatment al- so had better control efficiency to other cluster diseases, such as white rot, etc., and the control efficiency was almost the same as that of anthracnose. [Conclusion] It was suggested that the prevention concentration of 20% pyraclostrobin .200×10^8 cfu/g Bacillus subtili wettable powder to grape anthracnose after fruit setting and before bagging was 1 000-fold - 2 000-fold dilution. 展开更多
关键词 Grape anthracnose Bacillus subtilis PYRACLOSTROBIN MIXTURE Bacterio- static activity Field control efficiency
下载PDF
Use of Controlled Release Fertilizer for Increasing N Efficiency of Direct Seeding Rice 被引量:27
4
作者 FU JIANRONG, ZHU YUANHONG and JIANG LINA Institute of Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021 (China) 《Pedosphere》 SCIE CAS CSCD 2001年第4期333-339,共7页
Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilize... Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilizers) with the conventional urea. Six treatments including CK (no N fertilizer), conventional urea and different types of LP fertilizers at different rates were designed for two succeeding crops of early and late rice. A blend of different types of LP fertilizers as a single preplant "co-situs" application released N in a rate and amount synchronizing with uptake pattern of direct seeding rice. A single preplant application of the LP fertilizers could meet the N requirement of rice for the whole growth period without need of topdressing. Using LP fertilizer blends, equivalent grain yields could be maintained even if the N fertilization rates were reduced by 25%~50% compared with the conventional urea. Agronomic efficiency of the LP fertilizers was 13.6%~ 86.4% higher than that of the conventional urea in early rice and 100%~164.1% in late rice, depending on the amounts of the LP fertilizers applied. N fertilizer recovery rate increased from 27.4% for the conventional application of urea to 41.7%~54.l% for the single preplant "co-situs" application of the LP fertilizers. Use of the LP fertilizers was promising if the increase in production costs due to the high LP fertilizer prices could be compensated by increase in yield and N efficiency, reduction in labor costs and improvement in environment. 展开更多
关键词 controlled release fertilizer direct seeding rice N efficiency
下载PDF
Operation Efficiency Optimisation Modelling and Application of Model Predictive Control 被引量:2
5
作者 Xiaohua Xia Jiangfeng Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2015年第2期166-172,共7页
The efficiency of any energy system can be charaterised by the relevant efficiency components in terms of performance, operation, equipment and technology(POET). The overall energy efficiency of the system can be opti... The efficiency of any energy system can be charaterised by the relevant efficiency components in terms of performance, operation, equipment and technology(POET). The overall energy efficiency of the system can be optimised by studying the POET energy efficiency components. For an existing energy system, the improvement of operation efficiency will usually be a quick win for energy efficiency. Therefore, operation efficiency improvement will be the main purpose of this paper. General procedures to establish operation efficiency optimisation models are presented. Model predictive control, a popular technique in modern control theory, is applied to solve the obtained energy models. From the case studies in water pumping systems, model predictive control will have a prosperous application in more energy efficiency problems. 展开更多
关键词 Model predictive control(MPC) operation efficiency energy efficiency
下载PDF
Efficiency of a blue organic light-emitting diode enhanced by inserting charge control layers into the emission region 被引量:2
6
作者 白娟娟 吴晓明 +7 位作者 华玉林 穆雪 毕文涛 苏跃举 焦志强 申利莹 印寿根 郑加金 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期504-507,共4页
We demonstrate high current efficiency of a blue fluorescent organic light-emitting diode (OLED) by using the charge control layers (CCLs) based on Alq3 . The CCLs that are inserted into the emitting layers (EMLs... We demonstrate high current efficiency of a blue fluorescent organic light-emitting diode (OLED) by using the charge control layers (CCLs) based on Alq3 . The CCLs that are inserted into the emitting layers (EMLs) could impede the hole injection and facilitate the electron transport, which can improve the carrier balance and further expand the exciton generation region. The maximal current efficiency of the optimal device is 5.89 cd/A at 1.81 mA/cm2 , which is about 2.19 times higher than that of the control device (CD) without the CCL, and the maximal luminance is 19.660 cd/m2 at 12V. The device shows a good color stability though the green light emitting material Alq3 is introduced as the CCL in the EML, but it has a poor lifetime due to the formation of cationic Alq3 species. 展开更多
关键词 organic light-emitting devices charge control layer current efficiency
下载PDF
Increasing realism in modelling energy losses in railway vehicles and their impact to energy-efficient train control
7
作者 Michael Nold Francesco Corman 《Railway Engineering Science》 EI 2024年第3期257-285,共29页
The reduction of energy consumption is an increasingly important topic of the railway system.Energy-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruisi... The reduction of energy consumption is an increasingly important topic of the railway system.Energy-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruising speed to hold,how long one should coast over a suitable space,and when to brake.Most approaches in literature and industry greatly simplify a lot of nonlinear effects,such that they ignore mostly the losses due to energy conversion in traction components and auxiliaries.To fill this research gap,a series of increasingly detailed nonlinear losses is described and modelled.We categorize an increasing detail in this representation as four levels.We study the impact of those levels of detail on the energy optimal speed trajectory.To do this,a standard approach based on dynamic programming is used,given constraints on total travel time.This evaluation of multiple test cases highlights the influence of the dynamic losses and the power consumption of auxiliary components on railway trajectories,also compared to multiple benchmarks.The results show how the losses can make up 50%of the total energy consumption for an exemplary trip.Ignoring them would though result in consistent but limited errors in the optimal trajectory.Overall,more complex trajectories can result in less energy consumption when including the complexity of nonlinear losses than when a simpler model is considered.Those effects are stronger when the trajectory includes many acceleration and braking phases. 展开更多
关键词 Train trajectory optimization Energy-efficient train control(EETC) Dynamic efficiency Power losses in railway vehicles
下载PDF
Influence of Post Emergence Application of Glyphosate on Weed Control Efficiency and Yield of Transgenic Maize 被引量:1
8
作者 Duraisamy Ravisankar Chinnagoundar Chinnusamy Purushothaman Muthukrishnan 《American Journal of Plant Sciences》 2013年第8期1562-1567,共6页
Field experiment was conducted during kharif 2009 and rabi 2009-2010 at Tamil Nadu Agricultural University, Coimbatore to evaluate the weed control efficiency and yield potential of glyphosate resistant transgenic mai... Field experiment was conducted during kharif 2009 and rabi 2009-2010 at Tamil Nadu Agricultural University, Coimbatore to evaluate the weed control efficiency and yield potential of glyphosate resistant transgenic maize. Treatments consisted of two transgenic maize hybrids named Hishell and 900 M gold with application of glyphosate as post emergence at 900, 1800 and 3600 g a.e/hathese were compared with non-transgenic counterpart maize hybrids with application of atrazine as pre-emergence at 0.5 kg/ha followed by one hand weeding at 40 Days After Sowing along with need based insect control practices. Post emergence application of glyphosate at 900, 1800 and 3600 g a.e/ha in transgenic maize hybrids was recorded with lower weed density and higher weed control efficiency compared to other treatments. Higher grain yield was recorded with post emergence application of glyphosate at 1800 g a.e/ha in transgenic hybrid 900 M Gold and 3600 g a.e/ha in transgenic hybrid Hishell during kharif 2009 and rabi 2009-2010 seasons, respectively. 展开更多
关键词 GLYPHOSATE TOLERANT Maize WEED control efficiency YIELD
下载PDF
Function of controlled release fertilizer in maintaining high agronomic use efficiency and minimizing environmental pollution in rice field of southern China 被引量:2
9
作者 Ji Xionghui Luo Lanfang Zheng Shengxian 《Agricultural Science & Technology》 CAS 2006年第2期18-28,共11页
Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice fi... Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice field’s environmental contamination was discussed. Meanwhile, some suggestions were proposed. 展开更多
关键词 controlled release fertilizer ENVIRONMENT nutrient use efficiency rice yield
下载PDF
Effects of controlled-release urea application on the growth, yield and nitrogen recovery efficiency of cotton 被引量:1
10
作者 Suping Wang Xiaokun Li +7 位作者 Jianwei Lu Juan Hong Gang Chen Xinxin Xue Jifu Li Yunxia Wei Jialong Zou Guangwen Liu 《Agricultural Sciences》 2013年第12期33-38,共6页
Field experiments were conducted to study the effects of the controlled release urea (CRU) application on growth yield and nitrogen recovery efficiency of cotton in the main cotton zone of the Yangtze River basin in 2... Field experiments were conducted to study the effects of the controlled release urea (CRU) application on growth yield and nitrogen recovery efficiency of cotton in the main cotton zone of the Yangtze River basin in 2010. Different nitrogen levels were set in order to determine the suitable dosage of CRU on cotton. The special purpose was to provide evidence for the CRU application in cotton fields. The results show that the application of CRU promotes the growth of cotton significantly and enhances the nitrogen supply in the whole period. Compared to the treatment with total N as base fertilizer (UB), the bod, flower, little bolls and total bolls are increased significantly. There are no significant differences in the yield between the CRU treatment and the treatment of controlled release urea and urea combined application (60%CRU + 40%U), but an increase by 12.38%-22.67% compared to the UB treatment, and an increase by 4.49%-7.23% compared to the treatments of total N split application (UD). The nitrogen uptake of CRU treatment was significantly increased by 13.01%-48.32% and 30.27%-13.01% than UB treatment and UD treatment, respectively. The nutrient recovery efficiency of CRU treatment is increased by 16.42-20.59, 5.92-11.29 and 4.22-12.59 percentage points compared to the UB treatment, UD treatment and 60%CRU + 40%U treatment, respectively. In this study, there was a good linearity relationship between the cotton yield and amount of CRU in Wuxue site. The yield of cotton response to amount of CRU could be described by the model of linear plus plateau in Jingzhou site. 展开更多
关键词 controlled Release UREA COTTON YIELD NITROGEN Recovery efficiency
下载PDF
Efficiency Improvement of PEM Fuel Cells via Humidity Control 被引量:1
11
作者 Ahmad Haddad Louay Elsoufi +1 位作者 Marc Mannah Hasan Bazzi 《Journal of Control Science and Engineering》 2016年第1期26-35,共10页
PEM (Proton Exchange Membrane) fuel cell is a promising renewable energy source to a wide range of applications for its clean products and high power density. However, controlling its humidity is a challenging probl... PEM (Proton Exchange Membrane) fuel cell is a promising renewable energy source to a wide range of applications for its clean products and high power density. However, controlling its humidity is a challenging problem due to the interdependence of several phenomena contributing in membrane's water content. This work deals with efficiency improvement of PEM fuel cells via humidity control. An innovative strategy of control based on the model of Ref. [1] is proposed. It consists on regulating gas humidification rates according to the power demand so that to minimize power losses. The proposed control takes into consideration constraints related to humidification in order to avoid dry out or flooding of the membrane. Simulations results show that time-phasing between hydrogen and oxygen humidification rates plays an important role in minimizing power losses. The proposed control shows significant improvement in the fuel cell's efficiency up to 20%. 展开更多
关键词 PEM fuel cell mathematical modeling humidity control efficiency improvement.
下载PDF
Adiabatic cooling for cold polar molecules on a chip using a controllable high-efficiency electrostatic surface trap 被引量:6
12
作者 李胜强 许亮 +2 位作者 夏勇 汪海玲 印建平 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期148-154,共7页
We propose a controllable high-efficiency electrostatic surface trap for cold polar molecules on a chip by using two insulator-embedded charged rings and a grounded conductor plate. We calculate Stark energy structure... We propose a controllable high-efficiency electrostatic surface trap for cold polar molecules on a chip by using two insulator-embedded charged rings and a grounded conductor plate. We calculate Stark energy structure pattern of ND3 molecules in an external electric field using the method of matrix diagonalization. We analyze how the voltages that are applied to the ring electrodes affect the depth of the efficient well and the controllability of the distance between the trap center and the surface of the chip. To obtain a better understanding, we simulate the dynamical loading and trapping processes of ND3 molecules in a |J, KM = |1,-1 state by using classical Monte–Carlo method. Our study shows that the loading efficiency of our trap can reach ~ 88%. Finally, we study the adiabatic cooling of cold molecules in our surface trap by linearly lowering the potential-well depth(i.e., lowering the trapping voltage), and find that the temperature of the trapped ND3 molecules can be adiabatically cooled from 34.5 m K to ~ 5.8 m K when the trapping voltage is reduced from-35 k V to-3 k V. 展开更多
关键词 controlLABLE high-efficiency surface trap cold polar molecules
下载PDF
Control Efficiency of 36% Carbendazim Triadimefon SC on Wheat Powdery Mildew and Pink Mold
13
作者 Lu Jie Shao Mei 《Plant Diseases and Pests》 CAS 2015年第1期28-30,共3页
This paper explored the control efficiency of 36% Carbendazim triadimefon SC on wheat powdery mildew, wheat pink mold and rope sclerotinia, and the impact on rape yield through field experiment. The results showed tha... This paper explored the control efficiency of 36% Carbendazim triadimefon SC on wheat powdery mildew, wheat pink mold and rope sclerotinia, and the impact on rape yield through field experiment. The results showed that the control efficiency was the best on the 7th and 14th day after the application of 36% Car- bendazim triadimefon SC in the dosage of 2 250 mL/hm2, and rope yield was improved by 32%. 展开更多
关键词 Carbendazim triadimefon Wheat powdery mildew Wheat pink mold Rape sclerotinia control efficiency
下载PDF
Study on maximum efficiency control strategy for induction motor
14
作者 刘小虎 谢顺依 郑力捷 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第4期588-592,共5页
Two new techniques for efficiency-optimization control(EOC) of induction motor drives were proposed. The first method combined Loss Model and "golden section technique", which was faster than the available m... Two new techniques for efficiency-optimization control(EOC) of induction motor drives were proposed. The first method combined Loss Model and "golden section technique", which was faster than the available methods. Secondly, the low-frequency ripple torque due to decrease of rotor flux was compensated in a feedforward manner. If load torque or speed command changed, the efficiency search algorithm would be abandoned and the rated flux would be established to get the best transient response. The close agreement between the simulation and the experimental results confirmed the validity and usefulness of the proposed techniques. 展开更多
关键词 induction motor efficiency optimization control search controller golden section technique loss model controller
下载PDF
Improved Efficiency Test Method for the Motor Controller with SiC MOSFETs
15
作者 Wei Wang Qiang Song +1 位作者 Yiting Li Mukhtiar Ahmad 《Journal of Beijing Institute of Technology》 EI CAS 2020年第3期294-302,共9页
The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing experiments.To deal with this issue,an i... The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing experiments.To deal with this issue,an improved electrical measurement method for the motor controller efficiency is proposed in this paper,which is established by analyzing the power loss distribution and phase currents of the motor controller.It is demonstrated that the SiC MOSFET chips are the main power loss devices in the motor controller,accounting for more than 93.1%of the total power loss.The accuracy of the proposed method is compared with the traditional method in simulation.It shows that the test error of the efficiency obtained by the traditional method fluctuates on a large scale,which varied from 0.094%to 1.911%.Compared with the traditional method,the test error of the proposed method appears to be less than 0.083%,which provides significant guidance for the motor controller efficiency test and design. 展开更多
关键词 electrical measurement method motor controller efficiency power loss distribution SiC MOSFET
下载PDF
Energy Efficiency Improvement of an Industrial Crystallization Process Using Linearizing Control
16
作者 Cédric Damour Michel Benne +2 位作者 Lionel Boillereaux Brigitte Grondin-Perez Jean-Pierre Chabriat 《Journal of Crystallization Process and Technology》 2012年第2期44-54,共11页
This paper illustrates the benefits of a multivariable linearizing control approach applied to an industrial crystallization process. This relevant approach is declined according to two different strategies: first, a ... This paper illustrates the benefits of a multivariable linearizing control approach applied to an industrial crystallization process. This relevant approach is declined according to two different strategies: first, a setpoint tracking is proposed for the couple crystal mass/concentration, whereas a second way consists in tracking of crystal content and concentration. The controlled variables, unavailable online, are issued from an observer developed in previous works. The performance of these strategies, which application to cane sugar crystallization constitutes a real novelty, are compared with experimental data issued from a PID-controlled industrial plant. The results reveal a significant improvement of energy efficiency, leading to an economy of more than 10% of energy. 展开更多
关键词 Energy efficiency Improvement Linearizing control INDUSTRIAL control PHASE CHANGING CRYSTALLIZATION
下载PDF
Novel approach to harmonic control for Class F power amplifier with high power added efficiency 被引量:1
17
作者 Jin Boshi Wu Qun +1 位作者 Yang Guohui Kim Bumman 《仪器仪表学报》 EI CAS CSCD 北大核心 2007年第7期1176-1179,共4页
This paper presents a new topology to implement Class F power amplifier for eliminating the on-resistance (R_(ON))effect.The time-domain and frequency-domain voltage and current waveforms for Class F amplifier are ana... This paper presents a new topology to implement Class F power amplifier for eliminating the on-resistance (R_(ON))effect.The time-domain and frequency-domain voltage and current waveforms for Class F amplifier are ana- lyzed using Fourier series analysis method.Considering the on-resistance effect,the formulas of the efficiency,output power,dc power dissipation,and fundamental load impedance are given from ideal current and voltage waveforms.For experimental verification,we designed and implemented a Class F power amplifier,which operates at 850 MHz using MGaAs/GaAs Heterostructure FET(HFET)device,and analyzed the measurement results.Test results show that the maximum PAE of 67% can be achieved at 28 dBm output power level. 展开更多
关键词 F类功率放大器 功效 谐波控制 电阻 傅里叶级数
下载PDF
Empirical Analysis of Forest Pest Control Efficiency from 2003 to 2014 in China
18
作者 Cai Qi Cai Yushi +3 位作者 Sun Shibo Ding Huimin Ren jie Wen Yali 《Plant Diseases and Pests》 CAS 2017年第5期20-22,共3页
Three indexes including forest pest occurrence area,control area and input fund of 31 provinces from 2003 to 2014 were selected from Forestry Statistical Yearbook,to establish dynamic interaction index evaluation syst... Three indexes including forest pest occurrence area,control area and input fund of 31 provinces from 2003 to 2014 were selected from Forestry Statistical Yearbook,to establish dynamic interaction index evaluation system with clustering robust regression model and Stata 13. 0 software. Total forest pest control efficiency in China was determined according to the computing result of entropy method. Suggestions such as improving forest pest control efficiency,increasing service efficiency and input amount of forest pest control input funds were put forward. It will provide empirical basis for target management evaluation of forest pest control work and accountability system. 展开更多
关键词 Forest pest control efficiency Cluster robust regression model Entropy method
下载PDF
Efficacy of High-efficiency Formula Pesticides for Controlling Sesamia inferens Walker and Ceratovacuna lanigera Zehntner
19
作者 Yongde MA Xiaoyan WANG +3 位作者 Yinhu LI Hongli SHAN Rongyue ZHANG Yingkun HUANG 《Agricultural Biotechnology》 CAS 2023年第2期42-44,47,共4页
[Objectives]This study was conducted to screen high-efficiency formula pesticides and precise and efficient application techniques for the prevention and control of Sesamia inferens Walker and Ceratovacuna lanigera Ze... [Objectives]This study was conducted to screen high-efficiency formula pesticides and precise and efficient application techniques for the prevention and control of Sesamia inferens Walker and Ceratovacuna lanigera Zehntner.[Methods]Field efficacy trials were conducted using different combinations of 70%directed enhanced thiamethoxam seed treatment dispersible powder and 46%monosultap·Bacillus thuringiensis wettable powder.[Results]70%directed enhanced thiamethoxam ZF 450 g/hm^(2)+46%monosultap·B.thuringiensis WP 2250 g/hm^(2)had good control effects on both S.inferens and C.lanigera,so it was an ideal high-efficiency formula pesticide for controlling sugarcane S.inferens and C.lanigera.From January to May,combining with new plant or perennial root cultivation management,70%directed enhanced thiamethoxam ZF 450 g/hm^(2)can be evenly spread on sugarcane ditches and sugarcane stumps after being well mixed with fertilizers applied per hectare,and covered with soil in a timely manner,and during the peak incubation period of the first and second generation of S.inferens eggs from March to May,46%monosultap·B.thuringiensis WP 2250 g/hm^(2)was sprayed to the leaf surface in the mixture with water 675 kg with an electric backpack or a motorized sprayer.In such a way,the control efficacy on dead heart seedlings could reach over 89.8%,and that on C.lanigera could reach 100%.Meanwhile,it could effectively and concurrently control thrips,and the increases in yield and sugar content could reach 29310 kg/hm^(2)and 5.9 percentage points,respectively.[Conclusions]The promotion and application of the formula pesticide could achieve precise application and control of sugarcane pests,and improvement of sugarcane quality and planting efficiency,and help promote green prevention and control of sugarcane diseases and pests and the sustained high-quality development of the sugar industry. 展开更多
关键词 SUGARCANE efficient formula pesticide Accurate application of pesticides Sesamia inferens Walker Ceratovacuna lanigera Zehntner control efficacy evaluation
下载PDF
Design and Development of a New Control System for Improving Energy Efficiency and Demand Response
20
作者 Guillermo Escrivá-Escrivá 《Journal of Construction Research》 2020年第1期37-49,共13页
One of the best strategies for improving energy efficiency in any system is using the energy resources in the facilities properly.Using energy systems only when they are absolutely necessary is one of the best cost-be... One of the best strategies for improving energy efficiency in any system is using the energy resources in the facilities properly.Using energy systems only when they are absolutely necessary is one of the best cost-benefit ratio strategies,i.e.the best energy saving strategy is,not using it.The aim of this paper resides on introducing a new Energy Management and Control System(EMCS),developed by the authors,which has been installed at the Universitat Politècnica de València.Alongside the paper,the architecture,the components and the installation cost analysis of the EMCS,as well as management actions implemented in the university and the obtained results are presented.Furthermore,this innovative system has been designed to improve demand response in energy systems by providing consumers with a tool for responding actively to energy demands,and also to provide all the different electrical market agents with a communication and business platform for exchanging information. 展开更多
关键词 Energy efficiency Demand response control systems Web interface Energy saving
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部