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1.
LI Li 《保鲜与加工》1999,(5):122-124
Referring to T.KUSUDA's and the author's research results,the simplified energy_consumption methods and the detailed computer simulation methods are compared.The major reasons for discrepancies are analyzed.The major problems of the Chinese practical and simplified method for energy_consumption analysis are put forward.  相似文献   

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《保鲜与加工》2002,(6):100-105
Because of the different configurations of buildings to be constructed, the arrangement of the whole-raising-scaffold used for practical construction is not always the same, which results in difference of the internal force of the whole- raising-scaffold in application. Based on the abovementioned, in this paper, the design method of the whole-raising-scaffold is investigated, a mechanical model based on the three-span continuous beam is set up, the mechanical characteristics due to the action of various load of the whole-raising-scaffold under the worst working condition is analyzed. Then the calculating method for the internal force of its main structure can be found. Combining the internal force calculated by this method, the security of the scaffold can be verified. The method introduced by this paper can be used as a general method for the scaffold design.  相似文献   

4.
刘明池 《华北农学报》1996,11(4):99-103
采用3因素二次正交旋转回归设计的方法,研究了大白菜产量与氮、磷、钾施用量的关系,获得了施肥量与产量,纯收益和单株重相互关系的数学模型。对产量形成的3个因子间的主因子效应和交互作用进行了分析。并通过对三块试验地试验结果的比较,提出了正交旋转回归设计方法的适用性。  相似文献   

5.
It is necessary to simplify the capacity spectrum into bilinear form so as to get characteristic point of hysteretic bone curve(especially the yield point and the yielded stiffness),ductility and equivalent damping of the structure.Three general methods of calculating yield point and yielded stiffness of equivalent SDOF are introduced and the yield point and the yielded stiffness of three frame structures are compared using above given methods in this paper.The hysteretic bone curves of equivalent SDOF are decided by the equivalent yield force and displacement,the maximum plastic displacements of equivalent SDOF under rare earthquake are calculated,and it is compared with the maximum plastic displacements of member structures using nonlinear dynamic analysis.Finally,the advice of simplifying capacity spectrum is advanced.  相似文献   

6.
The society-economy-environment appraisal for construction project can help our government to control macro-economy, make correlation policy and formulate laws and draw up city plan.It has great influence on the sustainable development of our society and it is the demand of the law for the environment evaluation in China.This paper introduced the basic structure of society-economy-environment appraisal system for construction project and the thought of elements transaction.Using the method of AHP, the model of project analyzing and optimizing selection is designed.For the more, the methods of the optimizing models on the selected schemes are put forward.Finally, the integrative analysis has been made on the system design and appliance of this appraisal system.  相似文献   

7.
A Hitchhiker's Guide to Mixed Models for Randomized Experiments   总被引:14,自引:0,他引:14  
Designed experiments conducted by crop scientists often give rise to several random sources of variation. Pertinent examples are split‐plot designs, series of experiments and repeated measurements taken on the same field plot. Data arising from such experiments may be conveniently analysed by mixed models. While the mixed model framework is by now very well developed theoretically, and good software is readily available, the technology is still under‐utilized. The purpose of the present paper is, therefore, to encourage more widespread use of mixed models. We outline basic principles, which help in setting up mixed models appropriate in a given situation, the main task required from users of mixed model software. Several examples are considered to demonstrate key issues. The theoretical underpinnings are briefly sketched in so far as they are practically relevant for making informed use of mixed‐model computer packages. Finally, a brief review is given of some recent methodological developments, which are of interest to the plant sciences. A German version of this paper is available from the corresponding author upon request.  相似文献   

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四川盆地边缘山地和川中丘陵区是四川省农村劳动力的主要输出地。本研究分别选择沐川县和安岳县作为两区域的样本县,采用与人口规模成比例的分层概率抽样(PPS)方法,按3乡镇/县、3行政村/乡镇、5村民小组以上/行政村的标准抽取调查乡镇、行政村和村民小组,再用间隔法在村民小组内抽取农户(共6乡镇、27村、101村民小组和813户),通过农户问卷和综合分析,从县域和乡镇两个尺度进行两县域农村劳动力转移的比较研究。结果表明:(1)农村劳动力转移仍是川中丘陵区(安岳县)和盆地边缘山地(沐川县)农村劳动力配置的主要方式,但前者农村劳动力转移强度和压力远大于后者。(2)受区位、资源环境、农业结构和非农产业等因素综合作用,在县域尺度上安岳县农村劳动力以省外转移为主,且比以省内转移为主的沐川县转移强度大、女性比重高、转移带来的留守老年/未成年人等社会问题更为突出。(3)资源环境相对一致的安岳县在乡镇尺度上农村劳动力转移主要受社会经济因素影响,乡镇间转移强度、转移劳动力文化程度与女性比例、省外转移比重、就业行业分散程度等均与乡镇对外联系便捷度、经济条件呈正向变动。而资源环境与社会经济分异复杂的沐川县,其乡镇农村劳动力转移受资源环境和社会经济的双重影响,乡镇间转移劳动力的状况与转移强度差异复杂,但乡镇间转移流向和就业领域差异不大,转移带来的社会问题与转移强度呈正向关联。(4)今后应充分认识和重视安岳县所在的川中丘陵区农村劳动力流动及合理配置的难度和问题。同时,要根据自然与社会经济的分异实际,从县域与乡镇两个尺度因地制宜地促进其流动与合理配置:安岳县应将区域流动与就地转化相结合,并着力改善基础设施促进落后乡镇劳动力转移;而沐川县应逐步向就地转化过渡,着力于有条件乡镇就地转化的探索。此外,实施区域产业转型与农村劳动力流动的有效联动是两地的共同选择。  相似文献   

10.
This paper introduces analysis of RP HPLC for amino acids,which uses OPA/MCE and FMOC derivatives with two fluorescence detectors.The system's error is removed through Internal Standard,i.e.HCYS,HSER,NVAL,TPRO.Meanwhile,the method' accuracy is determined by relative error of recoverity with all kinds of amino acid's ramification.The result shows:it is an ideal method for amino acids'analysis with better sensitivity,detection limits and recoverity,overcoming the limitation by single ramification & only one detector.In addition,it gets over influent of the peak of NH 3 to column.And the relative error of retentive time is <5% & experiment of recycling is >90%,which explains credibility of the method.  相似文献   

11.
In order to realize optimization of production organization and put forward a reasonable calculation model for the turnover number of steel ladle, the turnover process and time of steel ladle are analyzed with steel ladle of Q steelmaking plant. Gantt charts of steel ladle turnover for single casting schedule and double casting schedule are drawn. Calculation model for turnover number of steel ladle is put forward by analyzing the relationship between casting schedule and the turnover time of steel ladle, and the accuracy of the model is verified by simulation method. Researches show that the turnover number of steel ladle can be reduced 1-2 by adjusting cast starting time, and have significance for the optimization of steel ladle production organization.  相似文献   

12.
为了给有关部门在土地合理利用和耕地保护方面提供有效地决策参考依据,基于统计数据,利用统计分析软件对长春市耕地原始数据进行归类汇总预处理,进而对研究对象作定量分析研究。2002年初至2008年末,长春市耕地总体呈波动增长态势;耕地变化比较活跃,且流入速率约是流出速率的2倍;林地和草地是耕地主要去向,新开荒地是主要来源;从空间分布来看,各市(县)耕地变化存在显著差异。社会经济的发展对耕地变化有重要的影响,地方政策法规是引导土地合理利用的关键因素之一。本研究表明,土地利用变化研究中,充分合理地利用有关统计数据能较精确、有效地反映地方行政单元的土地利用情况。  相似文献   

13.
Two high and flexible RC frame structures are analyzed;the paper explains the rise in the structural damping ratio and the base mode's drifting,and the modes coupling is caused by the greatly rising damping ratio.The paper also proposes that the modes coupling need be considered in the pushover analysis of the high and flexible RC frame structures.A CQC adaptive distribution for lateral forces in considering the modes coupling at every load step is given,and is compared with the traditional SRSS one.Meanwhile,some practical engineering suggestions are given.  相似文献   

14.
可持续发展度测算作为可持续发展进程研究的重要因素,是指引和实现可持续发展的桥梁。本文对可持续发展度测算理论进行了细化研究,并对不同测算方法进行了深入分析,且总结3种可持续发展度测算的数学模型。结果发现:评价指标的选择与指标权重的确定直接影响计算的结果,测算时应据研究对象的实况选取适当的方法,以保证可持续发展度测算的准确性和指导性。  相似文献   

15.
为了揭示耕层土壤有机质含量的空间变异规律,指导土壤肥力评价和管理工作,实现耕地资源的可持续利用,本研究通过土壤样本野外采样和分析,测定样本中土壤有机质的含量,在ArcGIS地理信息系统平台上,利用地统计分析模块中的克立格法分析文登市耕层土壤有机质的空间变异性,并对比选择最优的克立格插值模型。结果表明:文登市耕层土壤有机质拟合的最优理论模型是Tetraspherical模型;C0/sill值为0.86,耕层土壤有机质空间相关性很弱,耕作制度、施肥数量和种类、种植制度等人类活动的作用影响很大,这些人为活动使土壤有机质的空间相关性减弱,逐渐向均一化方向发展;耕层有机质含量处在较低水平,应改善耕作管理方式实现耕地资源的可持续利用。  相似文献   

16.
为了解中国东南区普通玉米的主要农艺性状间的关系进而指导育种实践,通过灰色关联度分析的方法,研究了10个玉米杂交种的产量及主要农艺性状间的关系,结果表明:2011QS04、2011QS05与其他8个品系产量差异达显著水平,因此推荐进入生产试验,品系2011QS09和品系2011QS01比对照增产不显著,建议再试验一年,其他品系均比对照减产,建议停止试验;关联度分析表明11个主要农艺性状与产量的关联度依次为:百粒重>穗长>行粒数>叶片数>雄穗分枝数>穗柄长度>穗粗>秃顶>穗位高>行粒数>株高。结合各性状间的关联度分析结果可知,在育种实践中应在保持适当株高的前提下,选择百粒重大、穗长较长、行粒数多,全生育期叶片数较多的品种。  相似文献   

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山区高油玉米高产优质栽培模式研究   总被引:1,自引:1,他引:1  
为探索在黔西北山区种植高油玉米高产优质的栽培模式,促进山区种植业结构调整,采用多元二次正交回归旋转组合设计,研究了高油玉米产量、产油量与四个主要栽培因子——种植密度及N、P、K肥施用量之间的关系,建立了数学模型,解析了各因素对产量、产油量的效应,通过计算机模拟寻优,筛选出了黔西北山区高油玉米高产优质的农艺综合方案:密度62463~63710株/ hm2;N肥(纯N)321.79~359.04kg/hm2;P肥(P2O5)319.94~345.32 kg/hm2;K肥(K2O)293.64~333.30 kg/hm2。  相似文献   

19.
Based on the fundamental principle of the fractal theory, the fractal characteristics of the decision making mapping model for manufacturing and its modeling process are discussed. The principle of modeling for defcision-making mapping models by the fractal theory is proposed.  相似文献   

20.
中国绿地空气微生物研究现状与展望   总被引:1,自引:1,他引:0  
周连玉  乔枫 《中国农学通报》2011,27(20):269-273
空气中广泛分布着细菌、真菌孢子、放线菌和病毒等生物粒子,而绿地具有杀菌、降尘、清洁空气等功效,对改善环境,提高人们生活品质具有重要意义。许多研究者开始关注绿地的抑菌功能,对绿地空气微生物的类型、浓度、粒径范围以及影响绿地空气微生物群落变化的因素进行了较系统的研究。笔者总结了中国绿地空气微生物的主要种类、检测内容以及变化动态,并简要探讨绿地空气微生物的发展前景,认为应进一步开展绿地空气微生物的毒理学研究以及植物协同抑菌功能是今后的研究方向。  相似文献   

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