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稻纵卷叶螟低龄幼虫防治适期的简化测报法 被引量:2
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作者 朱金城 《广东农业科学》 CAS CSCD 1990年第1期35-37,共3页
稻纵卷叶螟幼虫的常规防治适期预测方法,过去是从田间查幼虫化蛹进度,预测蛾始盛期,再加卵的发育历期就是防治适期。但是,在田间查幼虫化蛹进度的工作量很大,幼虫都在茂密的稻株基部枯叶化蛹,漏查蛹的机会很多,预测防治适期与田间的实... 稻纵卷叶螟幼虫的常规防治适期预测方法,过去是从田间查幼虫化蛹进度,预测蛾始盛期,再加卵的发育历期就是防治适期。但是,在田间查幼虫化蛹进度的工作量很大,幼虫都在茂密的稻株基部枯叶化蛹,漏查蛹的机会很多,预测防治适期与田间的实际发生,经验证往往有提早7天的误差。作者自1981年以来,进行一系列的室内外观察,现已研究出准确简易可行的方法预测低龄幼虫的防治适期。(一)雌蛾产卵前期观察为了准确预测幼虫防治适期,必须监测田间蛾始盛期,解剖观察雌蛾卵巢发育历期和卵的发育历期。 展开更多
关键词 稻纵卷叶螟 低龄幼虫 防治适期 简化测报法
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银杏超小卷叶蛾的蛹壳测报法 被引量:2
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作者 郭祝春 李金华 +3 位作者 印福女 林飞虎 张华俊 赵国平 《中国森林病虫》 北大核心 2013年第3期44-45,共2页
2007年—2012年在泰兴市采用蛹壳测报法预测银杏超小卷叶蛾Pammene ginkgoicola幼虫的发生时间及危害程度。结果显示:当树表累计蛹壳数占蛹壳总数的15%,50%和85%时,分别为成虫羽化始盛期、高峰期、盛末期;由成虫羽化高峰期至幼虫危害高... 2007年—2012年在泰兴市采用蛹壳测报法预测银杏超小卷叶蛾Pammene ginkgoicola幼虫的发生时间及危害程度。结果显示:当树表累计蛹壳数占蛹壳总数的15%,50%和85%时,分别为成虫羽化始盛期、高峰期、盛末期;由成虫羽化高峰期至幼虫危害高峰期,一般为14~17 d;在一定行政区域范围标准株树干表皮观察区域统计的蛹壳数为0,即该范围未发生危害;单位树表面积蛹壳数(个/m2)<10,10~20,20~40,>40,枝被害率分别为<4%,4%~7%,7%~10%,>10%。 展开更多
关键词 银杏超小卷叶蛾 蛹壳 测报法
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浙江省棉红铃虫性信息素规范化测报方法及其应用初报
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作者 杨樟法 吕仲贤 《浙江农业科学》 北大核心 1991年第3期136-138,共3页
自棉红铃虫(Pectinophora gossypillaSaunders)性信息素应用于测报以来,先后在全省22个产棉县(市)推广应用。根据我们在慈溪、萧山、余姚、椒江、平湖等主要棉区10多年的试验、验证,摸索出了一套利用性信息素规范化测报棉红铃虫发生的模... 自棉红铃虫(Pectinophora gossypillaSaunders)性信息素应用于测报以来,先后在全省22个产棉县(市)推广应用。根据我们在慈溪、萧山、余姚、椒江、平湖等主要棉区10多年的试验、验证,摸索出了一套利用性信息素规范化测报棉红铃虫发生的模式,在生产上发挥了较好应用效果。 展开更多
关键词 棉红铃虫 性信息素 测报法 浙江
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桃蛀果蛾的两项测报方法
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作者 谌有光 朱强 杜志辉 《中国果树》 1991年第1期44-45,共2页
桃蛀果蛾(桃小食心虫)是我国苹果、梨、桃、枣产区的一大害虫。以老熟幼虫结冬茧在果园土壤内越冬,次年春季出土做夏茧化蛹,成虫羽化后在果实上产卵,幼虫孵出后不久即蛀果为害。越冬幼虫出土时期的测报是进行地面适时施药的依据,田间卵... 桃蛀果蛾(桃小食心虫)是我国苹果、梨、桃、枣产区的一大害虫。以老熟幼虫结冬茧在果园土壤内越冬,次年春季出土做夏茧化蛹,成虫羽化后在果实上产卵,幼虫孵出后不久即蛀果为害。越冬幼虫出土时期的测报是进行地面适时施药的依据,田间卵发生情况调查则是树上喷药的指南。但目前生产上对越冬幼虫出土时期的测报,多采用埋茧罩笼法。 展开更多
关键词 桃蛀果蛾 测报法 果树
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九江县棉田中黑盲蝽的发生危害及简易测报方法的研究 被引量:2
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作者 胡贤彬 桑昌明 高品林 《江西棉花》 1991年第1期19-21,共3页
棉盲蝽是农田常见的重要害虫之一。危害棉花的盲蝽在我县发生的种类主要有绿盲蝽和中黑盲蝽两种。50年代末期以前,棉盲蝽发生较少,至70年代,盲蝽的危害逐渐加重,但危害尚不突出。进入80年代以后,棉盲蝽的危害日益加剧,已成为棉田常发性... 棉盲蝽是农田常见的重要害虫之一。危害棉花的盲蝽在我县发生的种类主要有绿盲蝽和中黑盲蝽两种。50年代末期以前,棉盲蝽发生较少,至70年代,盲蝽的危害逐渐加重,但危害尚不突出。进入80年代以后,棉盲蝽的危害日益加剧,已成为棉田常发性的必治害虫。究其原因,耕作制度的变化。 展开更多
关键词 棉田 黑盲蝽 发生 危害 测报法
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Seismic attributes optimization and application in reservoir prediction 被引量:7
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作者 Gao Jun Wang Jianmin +2 位作者 Yun Meihou Huang Baoshun Zhang Guocai 《Applied Geophysics》 SCIE CSCD 2006年第4期243-247,共5页
Petroleum geophysicists recognize that many parameters related to oil and gas reservoirs are predicted using seismic attribute data. However, how best to optimize the seismic attributes, predict the character of thin ... Petroleum geophysicists recognize that many parameters related to oil and gas reservoirs are predicted using seismic attribute data. However, how best to optimize the seismic attributes, predict the character of thin sandstone reservoirs, and enhance the reservoir description accuracy is an important goal for geologists and geophysicists. Based on the theory of main component analysis, we present a new optimization method, called constrained main component analysis. Modeling estimates and real application in an oilfield show that it can enhance reservoir prediction accuracy and has better applicability. 展开更多
关键词 Seismic attributes reservoir prediction component analysis and Daqing Oilfield.
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A Novel Systematic Method of Quality Monitoring and Prediction Based on FDA and Kernel Regression 被引量:2
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作者 张曦 马思乐 +2 位作者 阎威武 赵旭 邵惠鹤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期427-436,共10页
A novel systematic quality monitoring and prediction method based on Fisher discriminant analysis (FDA) and kernel regression is proposed. The FDA method is first used for quality monitoring. If the process is un-der ... A novel systematic quality monitoring and prediction method based on Fisher discriminant analysis (FDA) and kernel regression is proposed. The FDA method is first used for quality monitoring. If the process is un-der normal condition, then kernel regression is further used for quality prediction and estimation. If faults have oc-curred, the contribution plot in the fault feature direction is used for fault diagnosis. The proposed method can ef-fectively detect the fault and has better ability to predict the response variables than principle component regression (PCR) and partial least squares (PLS). Application results to the industrial fluid catalytic cracking unit (FCCU) show the effectiveness of the proposed method. 展开更多
关键词 quality monitori-ng -quality prediction Fisher discriminant analysis kernel regression fluid catalyticcracking unit
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Assessment of total suspended sediment concentrations in Poyang Lake using HJ-1A/1B CCD imagery 被引量:8
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作者 于之锋 陈晓玲 +3 位作者 周斌 田礼乔 袁小红 冯炼 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第2期295-304,共10页
We explored the potential of the environment and disaster monitoring and forecasting small satellite constellations (HJ-1A/1B satellites) charge-coupled device (CCD) imagery (spatial resolution of 30 m, revisit time o... We explored the potential of the environment and disaster monitoring and forecasting small satellite constellations (HJ-1A/1B satellites) charge-coupled device (CCD) imagery (spatial resolution of 30 m, revisit time of 2 days) in the monitoring of total suspended sediment (TSS) concentrations in dynamic water bodies using Poyang Lake, the largest freshwater lake in China, as an example. Field surveys conducted during October 17-26, 2009 showed a wide range of TSS concentration (3-524 mg/L). Atmospheric correction was implemented using the Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) module in ENVI with the aid of aerosol information retrieved from concurrent Terra/Moderate Resolution Imaging Spectroradiometer (MODIS) surveys, which worked well at the CCD bands with relatively high reflectance. A practical exponential retrieval algorithm was created between satellite remote sensing reflectance and in-situ measured TSS concentration. The retrieved results for the whole water area matched the in-situ data well at most stations. The retrieval errors may be related to the problem of scale matching and mixed pixel. In three selected subregions of Poyang Lake, the distribution trend of retrieved TSS was consistent with that of the field investigation. It was shown that HJ-1A/1B CCD imagery can be used to estimate TSS concentrations in Poyang Lake over synoptic scales after applying an appropriate atmospheric correction method and retrieval algorithm. 展开更多
关键词 total suspended sediment HJ-1A/1B CCD atmospheric correction retrieval algorithm Poyang Lake
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Dynamic alarm prediction for critical alarms using a probabilistic model
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作者 Jianfeng Zhu Chunli Wang +2 位作者 Chuankun Li Xinjiang Gao Jinsong Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第7期881-885,共5页
Alarm systems play important roles for the safe and efficient operation of modern industrial plants. Critical alarms are configured with a higher priority and are safety related among many other alarms. If critical al... Alarm systems play important roles for the safe and efficient operation of modern industrial plants. Critical alarms are configured with a higher priority and are safety related among many other alarms. If critical alarms can be predicted in advance, the operator will have more time to prevent them from happening. In this paper,we present a dynamic alarm prediction algorithm, which is a probabilistic model that utilizes alarm data from distributed control system, to calculate the occurrence probability of critical alarms. It accounts for the local interdependences among the alarms using the n-gram model, which occur because of the nonlinear relationships between variables. Finally, the dynamic alarm prediction algorithm is applied to an industrial case study. 展开更多
关键词 Dynamic alarm predictionAlarm managementThe n-gram modelAlarm sequence
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Determination of Effective Degree-Day for Supporting Chemical Control Against Cutworms (Lep. Noctuinae) in the Sugar Beet
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作者 Magdalena Jakubowska Felicyta Walczak JerzyJ6zefatLipa 《Journal of Agricultural Science and Technology(A)》 2012年第3期314-326,共13页
The aim of the research was to connect two methods of the chemical control. The first chemical treatments were applied according to the signalling method. The second method was applied according to the phonological cr... The aim of the research was to connect two methods of the chemical control. The first chemical treatments were applied according to the signalling method. The second method was applied according to the phonological criterion i.e., on the basis of the values of effective temperatures sums or heat sums for cutworms. The studies on cutworms infesting sugar beet crops were carried out in the years 2005-2008. The observation performed during the moth flights from May to September included two species, turnip moth (Agrotis segetum Den. & Schiff.) and heart-and-dart moth (A. exclamationis L.). The dynamics of moth flights was recorded in reference to readings of climatic conditions registered with the field meteorological stations set up near the light traps. Observations on cutworm occurrence during the vegetation season were done every 5-7 days. Moreover, additional studies were conducted under control conditions in the growth chambers at three programmed temperatures (17°C, 20 °C, 24 °C) and relative humidity (50%-70%). Based on the results the values for the heat sum of 501.1 °C and effective temperatures sum of 230.0 °C were determined for the developmental stages of cutworm. On the base of the results obtained it can be stated that the improved method of short-term forecasting can be an alternative solution in the integrated protection management against pest. 展开更多
关键词 Cutworms monitoring DEGREE-DAY sums of effective temperatures light trap sugar beet (Beta vulgaris L.).
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Influences of misprediction costs on solar flare prediction 被引量:3
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作者 HUANG Xin WANG HuaNing DAI XingHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第10期1956-1962,共7页
The mispredictive costs of flaring and non-flaring samples are different for different applications of solar flare prediction.Hence,solar flare prediction is considered a cost sensitive problem.A cost sensitive solar ... The mispredictive costs of flaring and non-flaring samples are different for different applications of solar flare prediction.Hence,solar flare prediction is considered a cost sensitive problem.A cost sensitive solar flare prediction model is built by modifying the basic decision tree algorithm.Inconsistency rate with the exhaustive search strategy is used to determine the optimal combination of magnetic field parameters in an active region.These selected parameters are applied as the inputs of the solar flare prediction model.The performance of the cost sensitive solar flare prediction model is evaluated for the different thresholds of solar flares.It is found that more flaring samples are correctly predicted and more non-flaring samples are wrongly predicted with the increase of the cost for wrongly predicting flaring samples as non-flaring samples,and the larger cost of wrongly predicting flaring samples as non-flaring samples is required for the higher threshold of solar flares.This can be considered as the guide line for choosing proper cost to meet the requirements in different applications. 展开更多
关键词 flares: forecasting sun: magnetic field cost sensitive learning
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Extended digital image correlation method for micro-region deformation measurement 被引量:9
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作者 CHEN JinLong ZHANG XiaoChuan ZHAN Nan 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第6期1355-1361,共7页
Extended digital image correlation(X-DIC) method is one novel test method in experimental mechanics.In this paper,the principle of the X-DIC method was introduced in detail.A selection scheme of the initial value of N... Extended digital image correlation(X-DIC) method is one novel test method in experimental mechanics.In this paper,the principle of the X-DIC method was introduced in detail.A selection scheme of the initial value of Newton iteration method was proposed when Newton iteration method was applied to solve the partial differential equations.This scheme could make the X-DIC method suitable for the large deformation measurement and avoid the non-convergence phenomenon effectively.The performance of the X-DIC method was verified by simulated images.Since the pixel point with the maximum absolute error occurred mainly at the corner or on the interface of the region of interest(ROI,region used for correlation calculation),measured deformation of the core area(area surrounding the center point of the ROI with a smaller size) was taken as the reliable measured value.The measurement accuracy of the X-DIC method could be improved greatly by using the core area.Combined with a long-distance microscope,the X-DIC method could be used in the deformation measurement of the micro-region.Zero deformation experiment was done to test the precision of the measurement system.Then,the X-DIC method was applied to measure the micro-region deformation of the specimen with a crack.Test value was proved to be in accordance with the actual deformation,showing that the X-DIC method is suitable for the research of microscale mechanical behavior of materials. 展开更多
关键词 extended digital image correlation(X-DIC) initial value core area micro-region deformation
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