CINRAD/SC多普勒天气雷达强度定标方法探究

为了提高雷达业务运行质量,对CINRAD/SC型号雷达原有的标定方法新引入天馈线衰减测量,并且给出合理的该型号雷达标定步骤,从而提高该型号雷达定标质量。利用信号源与功率计分别对雷达发射和接收部分进行衰减测量,给出了测量位置和测量方法;结合雷达方程和雷达工作原理,探讨出合理的该型号雷达标定方法。结合成都雷达站性能指标,分析了主要雷达参数性能对雷达回波强度的影响程度,最后给出了采用该定标方法前后的回波图对比。结果表明,采用此方法可以有效完成对雷达的标定,提高雷达定标质量。     

A Research on the Way of EMBET in the Tracking Systems'' Accuracy-analysis During Satellite Launch

In the past, the criterion for calibration has almost invariably been the stellar oriented ballistic camera,the method is a point to point comparison on the identical coordinate system. Deficiencies is follows: The request of weather is severe(cloudless night); The period is often long; the measure equipment of high precision can't be calibrated. While EMBET methods is used in calibration, it does not need criterion and it demands only that the measure elements is larger than 3,and the trajectory and many system errors of the measure elements can be simultaneously calculated with the measure data sequences. The error models of related equipments' measure elements and the EMBET of typical equipment group are given. The EMBET method is successfully used in Accuracy-analysis of Satellite Launch.     

Prediction of calibration interval for a measuring instrument using rolling grey bootstrap fusion model

A rolling grey bootstrap fusion model (RGBFM(1,1)) is proposed to predict calibration interval of a measuring instrument under small sample. The model combines GM(1,1) model with bootstrap method. Bootstrap re-sampling is used in the process of modeling the grey differential coefficient function to mine more information about systems. Both the instantaneous value and interval assessment values can be predicted using RGBFM(1,1), which can reduce prediction risk of calibration interval. In contrast, other prediction models only predict the instantaneous value. Experiments show that the RGBFM(1,1) can exactly describe the random wave of original sample data in prediction of instantaneous value, interval upper limit and lower limit, and has higher prediction reliability. Therefore, the RGBFM(1,1) is suitable for the prediction of calibration interval for a measuring instrument.     

Development of General Measurement & Control Software Platform for Automobile Components Test

This paper has discussed the characteristics of the development of automobile components test system.Based on the development example of vehicle hyraulic shock absorber test system,the paper has built general measurement & control software platform for automobile components tests,carved up main function modules along with the class libraries for platform,and adopts multi-thread technology to guarantee platform's real-time performance.The platform has enough flexible and extensible capability,and can satisfy the requirements of software developing for modern automobile components test system.     

基于加权最小二乘法的供水管网节点流量校核

管网水力模型是实现供水系统现代化管理的重要工具,要使水力模型能比较准确地反映管网真实运行状态,达到预期使用目的,其中的参数需要校核。将管网节点流量校核作为优化问题,采用加权最小二乘法逐步迭代求解,与已有研究相比,采用矩阵分析法推导供水管网雅克比矩阵解析式,引入水量分配矩阵聚合节点流量,将欠定问题转化为超定,提高了校核的计算效率和结果的可靠性。采用简单管网阐明了雅克比矩阵的计算、节点流量的聚合及梯度向量的构造,利用实际管网验证了方法的实用性。     

Probability Analysis of "Strong Beam and Weak Beam" and Axial Compression Ratio in RC Frame

In the view of reliability calibration, this paper analyzes the probabilistic sense of the provisions of "Strong Column and Weak Beam' and axial compression ratio in aseismic criteria (GBJ 11 89), which demonstrates that there is much difference between different aseismic ranks of RC frame. The authors suggest that it is possible to make axial compression ratio larger by adjusting the moment capacity ratio between column and beam. Finally, the direction and method of further studies are proposed.     

鸡粪便中氧氟沙星残留检测微生物法的建立

以金黄色葡萄球菌为工作菌, 用杯碟法测定氧氟沙星（OFL）在畜禽粪便中的残留。结果表明：鸡粪便中氧氟沙星的最低检测限为0.156μg/g,标准曲线的工作范围为0.156~5.00μg/g,工作曲线的日内变异系数在2.4%~3.3%、日间变异系数为3.7%~5.2%,回收率分别为79.49%~87.92%。因此,建立的方法可以满足鸡粪尿混合物中氧氟沙星的残留检测要求。     

典型黑土区土壤环境质量综合评价指标体系与分区管理对策研究

东北黑土区是中国重要的商品粮基地,但由于经济的快速发展和工农业水平的提高,造成区域水土流失严重,黑土层变薄,土壤肥力变差,区域内土壤环境质量逐年下降。从研究区实际情况出发,结合现存环境问题,通过对东北黑土区驱动力、土壤环境压力、土壤环境状态、土壤环境影响及响应5个方面出发,在驱动力-压力-状态-影响-响应(DPSIR)框架模型基础上,进行典型黑土区土壤环境质量指标筛选,建立由5大部分,18个一级指标,30个二级指标构成的指标体系。同时,以评价指标体系为指导,结合东北地区现有环境管理政策和存在的土壤环境质量问题,提出黑土区土壤环境分区分类管理方案,为区域土壤环境管理和土壤环境保护提供科学依据。     

平直节理黏结颗粒材料宏细观参数关系及细观参数的标定

为了分析平直节理黏结颗粒材料宏细观参数关系以及进行细观参数的标定,以单轴压缩、直接拉伸和双轴压缩数值试验作为宏观参数测试方法,对平直节理接触模型细观参数进行正交设计,采用多因素方差分析和回归分析研究宏细观参数之间的关系,在此基础上,建立了细观参数的标定方法。以灰岩的室内试验为基础,对其细观参数进行标定,模拟结果与试验结果相接近,验证了方法的有效性。     

Multi-model uncertainty analysis in predicting grain N for crop rotations in Europe

Realistic estimation of grain nitrogen (N; N in grain yield) is crucial for assessing N management in crop rotations, but there is little information on the performance of commonly used crop models for simulating grain N. Therefore, the objectives of the study were to (1) test if continuous simulation (multi-year) performs better than single year simulation, (2) assess if calibration improves model performance at different calibration levels, and (3) investigate if a multi-model ensemble can substantially reduce uncertainty in reproducing grain N. For this purpose, 12 models were applied simulating different treatments (catch crops, CO₂ concentrations, irrigation, N application, residues and tillage) in four multi-year rotation experiments in Europe to assess modelling accuracy. Seven grain and seed crops in four rotation systems in Europe were included in the study, namely winter wheat, winter barley, spring barley, spring oat, winter rye, pea and winter oilseed rape. Our results indicate that the higher level of calibration significantly increased the quality of the simulation for grain N. In addition, models performed better in predicting grain N of winter wheat, winter barley and spring barley compared to spring oat, winter rye, pea and winter oilseed rape. For each crop, the use of the ensemble mean significantly reduced the mean absolute percentage error (MAPE) between simulations and observations to less than 15%, thus a multi–model ensemble can more precisely predict grain N than a random single model. Models correctly simulated the effects of enhanced N input on grain N of winter wheat and winter barley, whereas effects of tillage and irrigation were less well estimated. However, the use of continuous simulation did not improve the simulations as compared to single year simulation based on the multi-year performance, which suggests needs for further model improvements of crop rotation effects.     

Comparison between Calibration Procedure and Econometric Estimation

The two methods of estimating parameter in computable general equilibrium(CGE) model are introduced and compared:the calibration procedure and econometric estimation. The conclusions are:the estimation of parameter in CGE model must use the calibration procedure coupled with the econometric estimation method;the elasticity of output with respect to labor input,the marginal expenditure share for households and price elasticity of export demand are estimated by econometric estimation method;and other parameters of the CGE model can be get by calibration procedure.     

物联网技术在农田环境监测中的应用

为了实现农业的自动化管理,为实现农业精准生产,并为科学研究提供全面信息,设计了基于物联网的农田环境监测系统,系统由传感层、传输层和应用层构成。开发了结构灵活、通用性强的路由和协调器节点,节点通过标准模拟接口与传感器连接,在此基础之上构建了具有高可靠性和灵活性的无线传感器网络,该网络能实时感知作物生长环境信息,并将数据可靠地传输到远端服务器管理系统。田间试验表明：基于物联网农田综合环境信息自动监测系统运行稳定、可靠,为科学预测和科学种植提供了依据。     

Research on Dynamics of Installation Way for Active Isolation Actuator on Flexible Foundations

The dynamic characteristic of active isolation atuator on flexible foundations was studied under the installation of parallel structure and foundation cancellation.The influencing relationships between active isolation force of the different installation ways and passive isolation system and flexible foundation were analyzed and compared.Scientific basis for selecting installation ways of active isolator is provided in this paper.     

An Unsteady Flow Analysis in Gas Transmission Pipeline Based on Theory of Functional Analysis

Branch -like pipeline is a common structure in gas transmission pipeline. In the light of the constituent properties of natural gas branch - like pipeline system, the system can be divided into fundamental constituent units. This paper presents a realistic unsteady flow model consisting of simple models of pipeline units and connecting conditions, boundary conditions and initial condition associated with units by using system analysis method. The solutions in wide sense are obtained by theory of functional analysis and operator series method, Such a method has the properties of both analytical solution and numerical solution methods. When the divided pipeline unit is larger, an intuitive approximate analytical solution may be obtained; while the one is smaller, a more accurate numerical solution may be acquired. Based on this, a general computer program has been developed for this model and solutions have been used successfully in a local natural gas transmission network in Sichuan. It is proved that the model and algorithm proposed in this paper are of the advantages of convenient calculation, high precision, time saving and wide application range by way of analysis and application.     

LINTUL3, a simulation model for nitrogen-limited situations: Application to rice

LINTUL3 is a crop model that calculates biomass production based on intercepted photosynthetically active radiation (PAR) and light use efficiency (LUE). It is an adapted version of LINTUL2 (that simulates potential and water-limited crop growth), including nitrogen limitation. Nitrogen stress in the model is defined through the nitrogen nutrition index (NNI): the ratio of actual nitrogen concentration and critical nitrogen concentration in the plant. The effect of nitrogen stress on crop growth is tested in the model either through a reduction in LUE or leaf area (LA) or a combination of these two and further evaluated with independent datasets. However, water limitation is not considered in the present study as the crop is paddy rice. This paper describes the model for the case of rice, test the hypotheses of N stress on crop growth and details of model calibration and testing using independent data sets of nitrogen treatments (with fertilizer rates of 0–400 kg N ha^?1) under varying environmental conditions in Asia. Results of calibration and testing are compared graphically, through Root Mean Square Deviation (RMSD), and by Average Absolute Deviation (AAD). Overall average absolute deviation values for calibration and testing of total aboveground biomass show less than 26% mean deviation from the observations though the values for individual experiments show a higher deviation up to 41%. In general, the model responded well to nitrogen stress in all the treatments without fertilizer application as observed, but between fertilized treatments the response was varying.     

影响脂肪酸值测定仪测试稳定性的条件研究

采用空白液作为试样,碱液浓度在0.01004 mol/L,环境温度在23℃左右条件下,测试脂肪酸值测定仪的测定条件对测试结果的影响,主要测试内容为：测定时间间隔和预热时间对测定结果稳定性的影响及仪器稳定性测试。     

Renovation of Flexible Landscapes in Urban Brownfield Sites

This paper introduced concept and modern thought of urban brownfield site and flexible landscape design, analyzed factors influencing the modernity, and pointed out significance and necessity of flexible landscape design. By analyzing realistic problems of urban brownfield site, this paper combined flexible design and renovation of brownfield landscape renovation, and proposed suggestions for the flexible landscape renovation of urban brownfield sites, so that renovation of urban brownfield landscape is not confined in renovation, but is more flexible and adaptive, and flexible design is positive for the renovation of urban brownfield landscapes.     

Idea, Management System and Planning Method of Urban Fringe Development

In this paper, the concept of urban fringe is introduced and the problems in society, economy and ecology that the urban fringe is facing are analyzed. The policy, participant system and method of planning for development of urban fringe is discussed from three aspects as: idea, system and technique of planning. The compromised mode of development combining scattering and growing, the updating of the community organization and corresponding flexible means of planning is presented.     

基于物联网的日光温室环境监测在线校准

温室环境条件特别是温度对于作物生长和发育具有十分显著的影响。日光温室调控的主要环境因子之一是温度。然而,自然环境下的光照对温度产生作用,影响空气温度的监测精度。采用机器学习中的支持向量机算法(SVM),对日光温室内的温度智能监测算法进行了研究,根据光照情况对实时监测的温度数据进行校准。通过与实验测量的数据进行对比分析,结果表明：所提出的监测方法可以较为准确地实时监测空气温度,从而无需使用隔热材料或者遮阳处理,就可以基于监测的数据更精确地对相应的环境因素进行调节。基于该方法,可采用常用的工业设备实现温室大棚内实时温度数据的监测,既可以节约设备和人力成本,又可以为温室控制提供准确的数据。     

高速逆流色谱技术在天然产物研究中的应用进展

高速逆流色谱是液-液分配色谱,与传统固-液分配色谱相比,其具有固定相成本低、易回收、分离过程灵活、高效等优点,近年来被广泛应用于天然产物研究中.本文总结归纳了高速逆流色谱的两相溶剂体系、分离洗脱方式的选择和应用方法,分析阐述了高速逆流色谱技术在天然产物研究中的应用实例,为天然产物功效成分的进一步深入研究提供可靠的技术参考.