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Eigenstructure assignment of lower-order dynamical compensatorsfor linear systems with unknown inputs

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Journal of Harbin Institute of Technology(New Series) 2000年第3期7卷 53-57页

作者：郭奔王明彦张福恩 Dept. of Electrical Engineering Harbin Institute of Technology Harbin 150001 China Dept. of Control Engineering Harbin Institute of Technology Harbin 150001 China

Presents a systematic design method of reduced order dynamical compensator via the parametric representations of eigenstructure assignment for linear system, which provides maximum degree of freedom, and can be easily used for the design of a linear system with unknown inputs under some conditions. Even when these conditions are not satisfied, the lower order dynamical compensator can also be designed under some relaxed conditions. Some examples illustrate that the method is neat, simple and effective.

关键词： Dynamical compensator eigenstructure assignment linear system unknown inputs

ADAPTIVE FORECAST AND CONTROL OF THE MARKET ECONOMIC SYSTEM WITH FUZZY inputs

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Journal of China Textile University(English Edition) 1996年第2期13卷 77-83页

作者：王文杰汤兵勇

In this paper, the adaptive forecast and control of the market economic system with fuzzy inputs is discussed. A new method which is adapted for the adaptive forecast and control of this kind of system is introduced. ... 详细信息

关键词： fuzzy inputs market economic system adaptive forecast and control

A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics

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Defence Technology（防务技术） 2019年第5期15卷 741-757页

作者： C.A.Rabbath D.Corriveau Defence R&D Canada Valcartier Research Centre

Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile.

关键词： Aerodynamic coefficients Piecewise polynomial functions Cubic splines Curve fitting Piecewise linear functions Piecewise cubic Hermite interpolating polynomial Projectile modelling and simulation Fire control inputs Precision Ballistic computer software

On bacterial role in hydrocarbon generation mechanism,Banqiao Sag

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Science China Chemistry 1995年第9期38卷 1123-1134页

作者：王铁冠钟宁宁侯读杰黄光辉于志海杨池银廖前进 Geosciences Department University of PetroleumBeijing 102200China Petroleum Geochemistry Laboratory Jianghan Petroleum InstituteJingsha 434102China Geological Exploration & Development Institute Dagang Oil FieldTianjin 300280China

Terrestrial organic matter is a main primary source material for oil and gas generation in theEogene Shahejie Formation in Banqiao Sag,bacterial degradation and reworking of sedimentary organic matterwould be conducive to the enhancement of its sapropelification level and to the early generation of immatureoil.Bacteria-derived short-chain alkanes are a major material base for the light hydrocarbon formation ofcondensate and crude oil in Banqiao Sag,certain thermal maturation,formation temperature and pressure areexternal conditions for the condemate formation.The establishment of hydrocarbon generation model shouldbe favorable to the resource prediction of deep-lying high-mature and shallow-lying immature oils and gases.

关键词： source inputs hydrogen-rich macerals mineral-bituminite groundmass hydrocarbon generation model.

Do Poor Rural Households Produce Less Grain than Non-poor Rural Households

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China & World Economy 2013年第6期21卷 22-36页

作者： Ling Ma Xiaoyun Liu Xian Xin College of Economics and Management and Center for Rural Development Policy China Agricultural University College of Humanities and Development China Agricultural University Center for Rural Development Policy China Agricultural University

China＇s poor rural households produce substantially less grain compared with non-poor rural households. The present paper applies a decomposition approach and uses China＇s rural household survey data to investigate the causes of this grain output gap The paper first compares the grain output gap between poor and non-poor rural households, and then decomposes the gap into differences in yield and area sown, The results indicate that the gap in grain output mainly results from differences in the amount of inputs used in production. Differences in the number of labor days and the level of intermediate inputs account for 13.6 and 47.S percent of the gap, respectively. Poor rural households are also less efficient in their use of intermediate inputs, which contributes to 13.2percent of the gap. However, the efficiency of poor households＂ labor days reduces the gap by 7.2 percent, while agricultural physical capital, househoM head education and agricultural training have no substantial impact on the household grain output gap.

关键词： decomposition grain output inputs poor

Assessing the Impacts of Variable Input Costs on Maize Production in Cameroon

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Agricultural Sciences 2020年第11期11卷 1095-1108页

作者： Elise Stephanie Mvodo Meyo Ivette Mbey Egoh Department of Agricultural Economics and Agribusiness Faculty of Agriculture and Veterinary Medicine University of Buea Buea Cameroon Foundation for Entrepreneurship Research and Development (FERD) Akonolinga Cameroon

Agricultural inputs are necessities in a production process just as food is a necessity for human survival. Production comes with the use of inputs. The cultivation of maize in Cameroon is predominantly dominated by smallholder farmers who use traditional methods and face drudgery. The current production level of maize in the country is declining and to meet consumption requirements, huge quantities of the commodity are imported. This study questions the impacts of variable input costs on maize production. inputs are building blocks of production costs;it is therefore important for maize farmers to be alerted on the effective use of farm inputs in order to obtain higher returns. Data were collected with the use of a structured questionnaire. They were analysed using descriptive statistics and OLS Regression techniques. Results show that on average per hectare, each maize farmer spends USD10.12 on seeds, USD28.90 on fertilizer, USD8.90 on labour, and USD13.28 on herbicides. The regression results show that estimated coefficients of unit costs of fertilizer, herbicides and labour were negative but insignificant while land and hybrid seeds were positive. Input subsidy is recommended as a policy instrument to lower prices paid by farmers.

关键词： inputs Maize Production Costs Cameroon

Potential Breeding for High Nitrogen Fixation in <i>Pisum sativum</i>L.: Germplasm Phenotypic Characterization and Genetic Investigation

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American Journal of Plant Sciences 2013年第8期4卷 1597-1600页

作者： R. Abi-Ghanem E. T. Bodah M. Wood K. Braunwart Department of Crop and Soil Sciences Washington State University Pullman USA Department of Horticulture Washington State University Pullman USA ProGene Plant Research Othello USA.

Nitrogen (N) is the most yield-limiting crop nutrient worldwide. Industrially produced N has increased in cost over the past years, and is unavailable in many regions around the globe. Biological N fixation by rhizobial bacteria is a great underutilized resource that this project aims to maximize. Grain legumes fix approximately 20 to 100 kg·N·ha-1·yr-1. The amount of N supplied by fixation is affected by genes and traits of both the bacterial and plant partners. The objectives of this study are to identify Pisum sativum varieties with high nitrogen fixation efficiency. This is achieved by germplasm screening and phenotypic evaluation of nodule formation, total plant nitrogen, and residual nitrogen in soil. Significant differences in plant total nitrogen among the various cultivated genotypes were found, with heritability of 0.57. These pea varieties left in the soil a residual N that varies between 11.21 to 65.018 kg.N.ha-1. Our findings reveal a unique opportunity for improving N fixation through genetic crossing and selection.

关键词： Nitrogen Fixation Field Peas Agricultural inputs

典型调查设计与参数估计──在拟建大中型水库移民工作中的应用

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河南广播电视大学学报 1994年第Z1期9卷 56-58页

作者：丁自鲜

典型调查设计与参数估计──在拟建大中型水库移民工作中的应用丁自鲜在大中型水库建设中，由于水库建成蓄水，库区将被淹没，同时水的侵蚀，又将引起阵岸的滑塌，因此居住在库区及其库区周围（以下简称库周）影响范围内的居民将移民。... 详细信息

典型调查设计与参数估计──在拟建大中型水库移民工作中的应用丁自鲜在大中型水库建设中，由于水库建成蓄水，库区将被淹没，同时水的侵蚀，又将引起阵岸的滑塌，因此居住在库区及其库区周围（以下简称库周）影响范围内的居民将移民。在国内外大中型水库建设的投资概算中...

关键词： production function equal quantity curve equal cost curve combined inputs