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Study on Optimum Fertilization Model of Potato Intercropped with Sugarcane
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作者 江泽普 廖青 +5 位作者 谭裕模 韦广泼 邢颖 汪羽宁 刘斌 梁潘霞 《Agricultural Science & Technology》 CAS 2013年第1期138-143,共6页
[Objective] The paper was to study the effects of different ratios of N, P and K on yield of potato intercropped with sugarcane in Lateritic red earth area of Guangxi, and seek the best N, P and K ratio for nutrition ... [Objective] The paper was to study the effects of different ratios of N, P and K on yield of potato intercropped with sugarcane in Lateritic red earth area of Guangxi, and seek the best N, P and K ratio for nutrition model of potato inter- cropped with sugarcane. [Method]Two field experiments adopted the optimum com- pound design (311-A) were conducted in Long'an County of Guangxi Province in 2011 and 2012, respectively. The polynomial regression models of fertilizer applica- tion and quadratic of three factors were established by SAS statistical analysis soft- ware, and optimum nutrient simulation models of potato were obtained by computer processing. [Result] The combined application of low nitrogen and mid-high potassi- um and phosphorus fertilizer contributed to higher potato yield in experimental condi- tion. The regression model of potato yield (Yll and Y12) and dosage of N(X1), P (X2), K(X3) were established by using SAS statistical analysis software, in 2011 and 2012, respectively. They were Y11 =14 725.28 -415.39X1 +741.99X2 +607.83)(3-447.92X1X2- 144.09X1X3 -405.83X2X3 -267.82X1^2-795.67X2^2 -642.10X3^2, R =0.927 2; and Y12 =14 342.60 -896.25X1 +548.62X2 +925.51 X3 +67.81 X1X2 +531.60X1X3 -99.00X2X3 -904.00X1^2 - 1121.36X2^2-596.64X3^2,R=0.926 6. The regression mathematics model of potato yields preferably fit with actual situation in the locality, and have higher practical value, so it could be used for fertilizer decision and forecast. Using the computer to carry on the optimization, the N, P and K dosage of the best potato yield intercropped with sugarcane was obtained. The dosage of N, P2O5, K2O were 108.8-140.6, 172.5-204.4 and 285.9 kg/hm2, respectively. [Conclusion] The best N, P and K ratio of potato yield intercropped with sugarcane was 1:(1.23-1.68):(2.03-2.63). 展开更多
关键词 INTERCROPPING optimum fertilization model Sugarcane-Potato
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ORPOM model for optimum distribution of tree ring sampling based on the climate observation network
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作者 Long Ma TingXi Liu +3 位作者 YanYun Luo HongLan Ji ShiQiang Li JunXiao Shi 《Research in Cold and Arid Regions》 2010年第6期547-554,共8页
Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree... Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree ring sampling sites based on climate information from the Climate Observation Network(ORPOM model) is presented in this article.In this setup,the tree rings in a typical region are used for surface representation,by applying excellent correlation with the climate information as the main principle.Taking the Horqin Sandy Land in the cold and arid region of China as an example,the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model,which is considered a reasonably practical scheme. 展开更多
关键词 CLIMATE monitoring network tree ring sampling site optimum model Horqin Sandy Land
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Ecological Optimum Population of Binzhou City Based on PEER Model
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作者 Chen Shuqing 《Meteorological and Environmental Research》 CAS 2019年第5期43-45,50,共4页
Taking into account the regional carrying capacity,the population capacity and optimum population of Binzhou City from 2007 to 2017 under certain economic,resource and environmental conditions were calculated based on... Taking into account the regional carrying capacity,the population capacity and optimum population of Binzhou City from 2007 to 2017 under certain economic,resource and environmental conditions were calculated based on PEER model.The results show that the population capacity of Binzhou City during 2007-2017 ranged from 6.03 million to 6.43 million,and ecological optimum population was between 5.05 million and 5.34 million.The actual population of the city was between 3.74 million and 3.94 million.The impact of the "two-child" policy on population growth was small,and there was still room for population growth.The population pressure index was greater than 0.7 and less than 1,showing that economic and resource population carrying capacity had certain surplus but were still not optimistic.Environmental pressure index was relatively high,and population carrying capacity was low. 展开更多
关键词 ECOLOGICAL optimum POPULATION POPULATION capacity PEER model Binzhou CITY
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The Disagreement between Anisotropic-Isotropic Diffuse Solar Radiation Models as a Function of Solar Declination: Computing the Optimum Tilt Angle of Solar Panels in the Area of Southern-Italy
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作者 Emanuele Calabrò 《Smart Grid and Renewable Energy》 2012年第4期253-259,共7页
In this paper a simulation to maximize the global solar radiation on a sloped collecting surface was applied to typical latitudes in the area of southern Italy, to calculate the optimum tilt angle of solar panels on b... In this paper a simulation to maximize the global solar radiation on a sloped collecting surface was applied to typical latitudes in the area of southern Italy, to calculate the optimum tilt angle of solar panels on building structures or large photovoltaic power plants located in that geographical area. Indeed, the area of southern Italy and in particular Sicily and Calabria are the top of European locations for acquiring solar energy. Some models of diffuse solar irradiance were taken into account to determine panels inclinations that maximized the impinging solar radiation by means of global horizontal solar radiation data provided from the Italian Institute of ENEA (Italy). An algorithm was used for the simulation providing a set of tilt angles for each latitude. The optimum tilt angle values obtained from the simulation resulted to be strictly related to the model of diffuse solar radiation that was used. Indeed, the disagreement between the values obtained using anisotropic models of diffuse solar radiation and those obtained from the isotropic model resulted to decrease significantly with increasing solar declination, showing that the isotropic model can be reliable only in summer months. 展开更多
关键词 Global SOLAR Radiation DIFFUSE SOLAR Irradiance ISOTROPIC model optimum Tilt Angle SOLAR Panel
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管梁截面形状与尺寸的协同优化研究
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作者 徐峰祥 王得伟 +1 位作者 方志刚 韦文儒 《机械科学与技术》 北大核心 2025年第2期199-207,共9页
管梁截面优化是汽车轻量化和性能设计的关键因素之一,管梁截面形状与尺寸的协同优化方法是底盘零部件设计的重要工作。本文提出了一种将形状和尺寸两种不同属性变量进行耦合的双超椭圆方程,并利用双超椭圆方程构建了任意曲边截面。针对... 管梁截面优化是汽车轻量化和性能设计的关键因素之一,管梁截面形状与尺寸的协同优化方法是底盘零部件设计的重要工作。本文提出了一种将形状和尺寸两种不同属性变量进行耦合的双超椭圆方程,并利用双超椭圆方程构建了任意曲边截面。针对任意曲边截面的优化,建立了截面自适应优化模型及多截面连续优化算法,该优化方法可自动进行形状优化、尺寸优化和形状等/变尺寸协同优化。对优化方案进行有限元分析显示,采用任意曲边截面优化得出的梁结构,梁横截面具有周向轮廓和厚度均匀过渡等优势,有效地减小了截面应力集中,提高了材料利用率,也为汽车机械零部件轻量化提供有效参考。 展开更多
关键词 截面优化 双超椭圆方程 任意曲边截面 截面自适应优化模型 优化方案
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再生粗骨料沥青混合料最佳沥青用量预测模型构建研究
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作者 王婧 陈莉 +2 位作者 赵绪峰 刘梦溪 张磊 《粘接》 2025年第11期89-92,共4页
采用6种再生粗骨料掺量0%、20%、40%、60%、80%和100%,分别以70号道路石油沥青和SBS(Ⅰ-D)改性沥青作为结合料,拌制AC-20中粒式沥青混合料,通过马歇尔试验确定沥青混合料的最佳沥青用量。结果表明,随着再生粗骨料掺量的增加,最佳沥青用... 采用6种再生粗骨料掺量0%、20%、40%、60%、80%和100%,分别以70号道路石油沥青和SBS(Ⅰ-D)改性沥青作为结合料,拌制AC-20中粒式沥青混合料,通过马歇尔试验确定沥青混合料的最佳沥青用量。结果表明,随着再生粗骨料掺量的增加,最佳沥青用量相应提高。对于70号道路石油沥青,最佳沥青用量较再生骨料掺量为0%的对照组增加了5.3%~38.0%;对于SBS(Ⅰ-D)改性沥青,最佳沥青用量较对照组增加了9.1%~35.5%。在相同再生粗骨料掺量条件下,SBS(Ⅰ-D)改性沥青混合料的最佳沥青用量较70号道路石油沥青混合料降低了约3%~10%。建立了最佳沥青用量与再生粗骨料掺量之间的关系曲线模型,通过对比模型计算结果与试验结果,发现采用70号道路石油沥青和SBS(Ⅰ-D)改性沥青时,最佳沥青用量的模型计算值与试验值之间的最大偏差均在3%左右,验证了所提出模型的适用性。 展开更多
关键词 再生粗骨料 70号道路石油沥青 SBS(Ⅰ-D)改性沥青 最佳沥青用量 曲线模型
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基于SIDBO-BP的采空区稳定性预测及应用
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作者 贺国庆 陈俊智 《黄金科学技术》 北大核心 2025年第2期295-303,共9页
针对传统方法无法精确进行采空区稳定性预测的问题,提出了一种基于SIDBO-BP的采空区稳定性预测方法。从采空区内外部2个方面进行考虑,确定了影响采空区稳定性的9个因素作为特征值,构建了基于SIDBO-BP的采空区稳定性预测模型。以云南省... 针对传统方法无法精确进行采空区稳定性预测的问题,提出了一种基于SIDBO-BP的采空区稳定性预测方法。从采空区内外部2个方面进行考虑,确定了影响采空区稳定性的9个因素作为特征值,构建了基于SIDBO-BP的采空区稳定性预测模型。以云南省某铅锌矿93组采空区作为研究对象,使用准确率、精确度、特异性、召回率和F1_Score共5个指标对模型的预测结果进行评估,并与其他算法模型进行对比。结果表明:SIDBO-BP模型预测结果的准确率、精确度、特异性、召回率和F1_Score均大于其余算法模型,且与实际结果基本吻合,说明基于SIDBO-BP的采空区稳定性预测方法具有更好的性能且预测效果更理想。 展开更多
关键词 机器学习 采空区 稳定性预测 局部最优 SIDBO-BP模型 评估指标
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海上古近系古潜山凝析气藏开发井网优化研究
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作者 廖爽 朱旭晨 +4 位作者 王飞 王敬 寇双燕 孟凡嵩 董凯文 《化工管理》 2025年第24期161-164,共4页
文章以渤海西南部海域B气田为实例,针对古近系潜山储层巨厚、岩性复杂、裂缝发育、非均质严重的特点,构建了嵌入式离散裂缝凝析气藏数值模拟模型。该模型依据“砂砾岩-风化带-内幕带”地质模式,分别探究了直井、水平井、多分支水平井和... 文章以渤海西南部海域B气田为实例,针对古近系潜山储层巨厚、岩性复杂、裂缝发育、非均质严重的特点,构建了嵌入式离散裂缝凝析气藏数值模拟模型。该模型依据“砂砾岩-风化带-内幕带”地质模式,分别探究了直井、水平井、多分支水平井和鱼骨井等不同井型的适应性,通过综合对比优选最佳井型与参数。研究表明,潜山顶部低渗砂岩最佳井型为水平井,最佳水平段长度为1 200 m;风化带最佳井型为多分支水平井,主井筒长度1 000 m、分支总数6、分支井与主井筒夹角成45°、分支井筒长度200 m;内幕带最佳井型为水平井,最佳水平段长度1 200~1 400 m。 展开更多
关键词 古近系古潜山 凝析气藏 数值模拟 井网优化
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冲积河流平滩流量滞后响应前期影响权重优化
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作者 申红彬 张小峰 +2 位作者 王海周 陈翠霞 陈建 《水科学进展》 北大核心 2025年第3期505-515,共11页
确定前期水沙条件影响权重是研究河道平滩流量滞后响应的难点问题。考虑前期水沙条件影响权重的复杂变化,对河道平滩流量提出建立前期水沙条件与影响权重的卷积模型,并为确定前期水沙条件影响权重给出一种简易的相关分析方法。对比现有... 确定前期水沙条件影响权重是研究河道平滩流量滞后响应的难点问题。考虑前期水沙条件影响权重的复杂变化,对河道平滩流量提出建立前期水沙条件与影响权重的卷积模型,并为确定前期水沙条件影响权重给出一种简易的相关分析方法。对比现有河道平滩流量滞后响应模型的滑动平均、速率方程方法,均可视为卷积模型前期水沙条件影响权重为特定函数时的特例。选择黄河内蒙古河段三湖河口站为例,分别采用3种模型方法对平滩流量变化过程进行模拟。研究结果表明:效果从高到低依次为卷积模型、滑动平均、速率方程,相应确定性系数分别为0.906、0.903、0.879,Nash-Sutcliffe效率系数分别为0.906、0.899、0.874;比较3种模型方法前期水沙条件影响权重,变化差别较大,说明优化选择前期水沙条件影响权重有助于提高模拟效果;分析卷积模型方法优化确定的前期水沙条件影响权重变化规律,平滩流量综合受当年与前6~8 a水沙条件的影响较强,表现出复杂的“双重”影响。 展开更多
关键词 平滩流量 滞后响应 卷积模型 前期影响权重 优化
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模拟平流沉淀池建立耙吸挖泥船装舱溢流最优效率模型
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作者 袁剑 徐军 《港口航道与近海工程》 2025年第2期121-125,共5页
耙吸挖泥船是疏浚行业举足轻重的重型施工船舶,其广泛应用于世界港口航道疏浚与人工岛吹填等工程。上世纪末开始我国的疏浚装备与技术有了飞速的发展,时至今日早已具有自主建造具有国际先进水平的“国之重器”的能力。未来疏浚施工技术... 耙吸挖泥船是疏浚行业举足轻重的重型施工船舶,其广泛应用于世界港口航道疏浚与人工岛吹填等工程。上世纪末开始我国的疏浚装备与技术有了飞速的发展,时至今日早已具有自主建造具有国际先进水平的“国之重器”的能力。未来疏浚施工技术将以船舶的全自动智能疏浚系统和岸基施工辅助决策系统为主要研究方向。本文介绍了以舱内沉淀效果较差的细颗粒土质为研究对象,通过模拟平流沉淀池模拟泥沙沉淀速度的测定、有效沉淀效率的计算,最终建立耙吸挖泥船装舱溢流最优效率模型,从而提高疏浚施工的单船施工效率,也为智能疏浚中自动装舱控制系统的研发提供了一定的理论与实践基础。 展开更多
关键词 平流沉淀池 粉砂粉土 泥舱沉降模型 最佳进舱流量 有效沉淀效率
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Reliability-Based Full-Life Cycle Optimum Design of Offshore Jacket Platform 被引量:1
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作者 王立成 宋玉普 《海洋工程:英文版》 2004年第1期47-58,共12页
Based on the consideration of operation environment and structural property, an optimum design model of offshore jacket platform is developed in this paper, namely, the reliability-based full-life cycle optimum design... Based on the consideration of operation environment and structural property, an optimum design model of offshore jacket platform is developed in this paper, namely, the reliability-based full-life cycle optimum design model. In this model, the time-dependent reliability assessment method for structural members is established by combination of the decrease of sectional size and performance deterioration of material. The initial investment, maintenance cost and failure loss cost are assembled into the model. The total cost of the platform structure system in its full service period is chosen as the objective function, and the initial reliabilities of the layer elements partitioned in advance are taken as the design variables. Different models are obtained, depending on whether the system reliability constraint is considered or not. This optimum design model can result in the lowest full-life cost and the optimal initial layer reliability of an offshore jacket platform in the design of marine structures. The feasibility of this model is illustrated with an actual jacket platform in the Liaodong Gulf as an example. 展开更多
关键词 offshore jacket platform full-life cycle optimum design model maintenance cost failure loss cost RELIABILITY
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Optimum municipal wastewater treatment plant design with consideration of uncertainty 被引量:2
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作者 ZENGGuang-ming LINYu-peng QINXiao-sheng HUANGGuo-he LIJian-bing JIANGRu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期126-131,共6页
A newly developed model for the optimum municipal wastewater treatment plant(MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by... A newly developed model for the optimum municipal wastewater treatment plant(MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by the fluctuation of the wastewater quality and quantity during the design of MWTP. The model solution procedure is illustrated in detail, and a numerical example is given to verify the feasibility and advantage of the model. Furthermore, the possibility of the model application is briefly outlined. 展开更多
关键词 UNCERTAINTY municipal wastewater treatment plant optimum design model
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HYPERSTATIC STRUCTURE MAPPING MODEL BUILDING AND OPTIMIZING DESIGN 被引量:2
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作者 XU Gening GAO Youshan +1 位作者 ZHANG Xueliang YANG Ruigang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期55-59,共5页
Hyperstatic structure plane model being built by structural mechanics is studied. Space model precisely reflected in real stress of the structure is built by finite element method (FEM) analysis commerce software. M... Hyperstatic structure plane model being built by structural mechanics is studied. Space model precisely reflected in real stress of the structure is built by finite element method (FEM) analysis commerce software. Mapping model of complex structure system is set up, with convenient calculation just as in plane model and comprehensive information as in space model. Plane model and space model are calculated under the same working condition. Plane model modular construction inner force is considered as input data; Space model modular construction inner force is considered as output data. Thus specimen is built on input data and output dam. Character and affiliation are extracted through training specimen, with the employment of nonlinear mapping capability of the artificial neural network. Mapping model with interpolation and extrpolation is gained, laying the foundation for optimum design. The steel structure of high-layer parking system (SSHLPS) is calculated as an instance. A three-layer back-propagation (BP) net including one hidden layer is constructed with nine input nodes and eight output nodes for a five-layer SSHLPS. The three-layer structure optimization result through the mapping model interpolation contrasts with integrity re-analysis, and seven layers structure through the mapping model extrpulation contrasts with integrity re-analysis. Any layer SSHLPS among 1-8 can be calculated with much accuracy. Amount of calculation can also be reduced if it is appfied into the same topological structure, with reduced distortion and assured precision. 展开更多
关键词 Plane model - Space model Artificial neural networks Mapping model optimum design
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古气候数据同化重建早始新世气候适宜期全球海水表面温度
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作者 张昊勋 李明松 《高校地质学报》 北大核心 2025年第3期275-285,共11页
早始新世气候适宜期(EECO,53.26~49.14 Ma)全球温度在百万年尺度上达到最高值,是66 Ma以来最温暖的时期,是政府间气候变化委员会(IPCC)第六次评估报告最极端的共享经济路径情景SSP8.5未来全球温度的地质参考时期。前人利用地球系统模式... 早始新世气候适宜期(EECO,53.26~49.14 Ma)全球温度在百万年尺度上达到最高值,是66 Ma以来最温暖的时期,是政府间气候变化委员会(IPCC)第六次评估报告最极端的共享经济路径情景SSP8.5未来全球温度的地质参考时期。前人利用地球系统模式和古气候替代指标,对EECO全球海水表面温度状态进行了重建。然而,地球系统模式的边界条件往往缺乏约束,难以重建准确的EECO全球海水表面温度状态;古气候替代指标重建结果之间存在分歧、且具有全球耦合性差等不足。该研究利用新兴的古气候数据同化技术,开展中等复杂程度地球系统模式cGENIE模拟,考虑大气二氧化碳浓度、碱度和雨比率三种不确定性因素,以100个模拟试验结果作为先验估计,融合了35个大洋钻探点位的三种古海水温度指标,即TEX86、浮游有孔虫Mg/Ca和δ^(18)O,高精度地重建了EECO时期全球耦合的海水表面温度。数据同化得到的全球海水表面温度为30.7℃(95%置信区间为28.8~33.0℃),同化结果具有全球耦合的特点,与地球系统模式模拟的先验值相比精度显著提高。开展了敏感性实验,证实不同替代指标类型对数据同化重建结果有显著的影响,去除TEX86指标数据同化得到的海水表面温度偏冷,而去除δ^(18)O指标的同化结果则偏热。本研究对EECO热室时期开展高精度的全球海水表面温度重建,为未来气候变化的这一关键地质参考型提供了更为精确的约束。 展开更多
关键词 古气候数据同化 早始新世气候适宜期 海水表面温度 古气候替代指标 地球系统模式
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秋月梨最佳采收期近红外光谱预测:考虑环境光变化和仪器台间差校正
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作者 孙旭东 龙涛 +4 位作者 王加华 冯绍然 曾体伟 谢冬福 付伟 《光谱学与光谱分析》 北大核心 2025年第10期2774-2782,共9页
适时采收是提高秋月梨果实采收优质率和贮藏品质的重要科学探索。果园环境光变化和仪器台间差会导致实验室内建立的预测树上果实品质数学模型的性能下降。为了减少果园环境光变化和仪器台间差的影响,采用全局模型、外部参数正交化(EPO)... 适时采收是提高秋月梨果实采收优质率和贮藏品质的重要科学探索。果园环境光变化和仪器台间差会导致实验室内建立的预测树上果实品质数学模型的性能下降。为了减少果园环境光变化和仪器台间差的影响,采用全局模型、外部参数正交化(EPO)方法对环境光影响和仪器台间差进行校正,并预测秋月梨的最佳采收期。采用2019年到2020年之间采集的599枚秋月梨样品建模,80枚秋月梨作为差异矩阵样品,2023年7月至9月采集的120枚秋月梨作为预测集。经过全局模型和EPO校正后,偏最小二乘回归(PLSR)模型的预测能力均有提高,全局模型最优、EPO次之。经过全局模型校正后,仪器A的模型预测仪器B的数据,决定系数由0.11提高到0.68,可溶性固形物(SSC)的预测均方根误差(RMSEP)由1.2%降低到0.69%。同时进行台间差和环境光变化全局模型校正后,决定系数由0.46提高到0.79,RMSEP由1.23%降低到0.70%。采用全局模型修正后的最佳模型预测最佳采收期,手持式仪器的预测结果与破坏性分析结果一致性较好,实验果园的最佳采收期为2023年8月26日,55%的采样秋月梨SSC含量超12%,满足采收标准。结果表明,全局模型校正能同时有效减小仪器台间差和环境光变化对模型预测性能的影响。本研究验证了采收期预测能提高秋月梨的采收品质,为秋月梨最佳采收期无损预测提供了参考。 展开更多
关键词 近红外光谱 可溶性固形物含量 手持式光谱检测仪 最佳采收期 光谱差矩阵 外部参数正交化 全局模型
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Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application 被引量:2
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作者 Luo, Youxin Chen, Mianyun +1 位作者 Che, Xiaoyi He, Zheming 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期17-21,共5页
To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) ... To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. 展开更多
关键词 grey system data processing Verhulst GM(1 1) non-equal interval direct modelling optimum background value two times fitting
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The Application of Optimum Decision in Oilfield Development 被引量:1
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作者 Zhang Zaixu Xu Qingshan +1 位作者 Jiang Megifang Hou Fenghua & Yin Aizhen(University of Petroleum of Shandong, Dongying 257061, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第2期5-10,共6页
The major steps of oilfield development are given in this paper. The optimal model of oilfield development is built and the methods of optimum decision analysis are studied. The solution and analysis of the optimal ta... The major steps of oilfield development are given in this paper. The optimal model of oilfield development is built and the methods of optimum decision analysis are studied. The solution and analysis of the optimal tactics have been set up according to the data collected in the oilfield. 展开更多
关键词 optimum tactics Oilfield development Optimizing model Decision analysis
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Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice 被引量:1
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作者 YAN Li-Jiao YAO Zhong ZHENG Zhi-ming LI Hua-bin 《Agricultural Sciences in China》 CAS CSCD 2006年第7期498-505,共8页
The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, ... The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively. 展开更多
关键词 SIMULATION model potential production optimum population quantitative indices second hybrid rice
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Economic-Mathematical Method to Determine the Optimum Production in Underground Coal Mine
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作者 Shaowen Zhang Xiangyi Li Zhongxui Li Guangcheng Wang Resources Engineering School, UST Beijing, Beijing 100083, China 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1998年第2期57-60,共4页
A method to determine optimum production is presented. First, based on analysis of various geological, technological and economic factors that influence the determination of underground mine capacity, a feasible range... A method to determine optimum production is presented. First, based on analysis of various geological, technological and economic factors that influence the determination of underground mine capacity, a feasible range of production capacity is selected. Second, by means of scale economic theory and depletion feature of mineral resounce, an economicmathematical model that aimed at maximum net profit in the whole life of mine is developed to optimum production. The model was tested in a undergrond mine. 展开更多
关键词 production of mine optimum economic-mathmatical model depletion
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Symmetry and conservation laws for optimum design of open pit mines
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作者 石忠民 《中国有色金属学会会刊:英文版》 CSCD 2000年第1期119-122,共4页
The classical physics theory respectively obeys the three famous conservation laws referred to as charge conjugation, parity and time reverse, and the open pit block model is equal to a Newtonian mechanics system. Con... The classical physics theory respectively obeys the three famous conservation laws referred to as charge conjugation, parity and time reverse, and the open pit block model is equal to a Newtonian mechanics system. Consequently, there would exist some correspondent symmetry principles and conservation laws within the 3D fixed block model of the deposit and the theory for the optimum design of the open pit mine. Reversing a series of relevant fundamental concepts, several conservation laws, which the theory for the optimum design of open pit mines should obey, as block weight conjugation, block model parity and combined symmetry of the both, were expounded. From the symmetry principle, the theoretic significance for a series of the current optimum techniques was discussed and explained, and a kind of conjugate heuristics which can check the error of itself was presented and demonstrated. Thus it is shown that the symmetry principle lays the foundations and opens up the prospects for the further research with mine design and scheduling problem. 展开更多
关键词 open PIT MINE optimum design BLOCK model SYMMETRY CONSERVATION
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