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To provide various production for fulfilling the customer's requirements to the market has been the goal of manufacturing enterprises. The order form is the representation of customer's requirements. It has been the headstream and end-piont of the management of enterprises and SCM. The idea and it's realization of SCM to the whole process are introduced, that is driven by the order form. It's derived from several aspects, including the characteristics of the production's configuration, the type of order form and supplying, the manufacture organizing mode and the material requirements, the way of SCM in manufacturing enterprise and the model of SCM to the whole process driven by order form, realizing technique, etc.  相似文献   

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蔡清 《中国农学通报》2011,27(31):300-304
景观不仅是一门艺术,更是一门科学。在对景观环境分析的基础上,提出点、线、面是景观造型的基本元素。结合平面构成理论,笔者指出平面构成理论与景观造型的基本元素之间存在形态要素的对应性、美学法则的一致性、形态语言的互通性等3个方面共性。因此,可利用平面构成理论对景观环境的营造进行指导。基于以上观点,以形态要素点、线、面的品质为出发点,探讨景观造型的基本元素的运用特点及手法,从而总结出景观造型的基本元素在景观设计中的应用特点及规律。  相似文献   

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The present study is to investigate the differences of Hg,Cr,Pb,Cd and Zn contents among water area ecology stystems of the three gorges Reservoir from water,dirt mud of the bottom and benthic fishes.The result show that content distribution of trace elements is:dirt mud of the bottom>benthic fishes>water;content distribution of trace elements in benthic fishes is:viscera>muscle>bone.The distribution factor of dirt mud of the bottom versus water,adsorption coefficient of benthic fishes versus dirt mud of the bottom and enrich coefficient of benthic fishes versus water is constant value in three Gorges Reservoir.Mercury is harm element to human in food chain.Besides,transform model of food chain in trace element are studied.  相似文献   

7.
The edge finite element interpolation function of 1-forms for prism is derived.The electrical field intensity is used as the unknown variable.If the tangential component of electrical field intensity is an enforcing condition on the interface of eddy-current region and non-eddycurrent region,the tangential component of magnetic field intensity is a natural continuous condition.At last,the mixed elements of prism and hexahedron are used to compute a three dimensional eddy-current problem.  相似文献   

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This paper points out that the price, quality, the level of supplying on time, the level of after-sales service and so on can be regarded as resources that the suppliers can provide, and proposes a concept called the comprehensive level of resources exploitation which can be used to evaluate the comprehensive effect of order quantities allocation of one product between several suppliers. A relative index is presented to measure the comprehensive level of resources exploitation. The index is fit for comparison between several order quantities allocation plans in different time to evaluate which plan exploits the resources of suppliers more effectively. Finally, this paper establishes a linear programming model to solve the optimal order quantities allocation based on the highest comprehensive level of resources exploitation.  相似文献   

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朱海涛 《中国农学通报》2019,35(22):123-129
基于长江源区1956-2012年水文气象资料,采用集中期和集中度、突变检验、小波变换等方法,分析了长江源区沱沱河站和直门达站年径流变化的趋势性、突变性和周期性,并从相关性和径流系数变化方面探讨了径流变化对气象要素的响应。结果表明:长江源径流年内分配的集中程度呈弱增加趋势,集中期均呈弱延后趋势。沱沱河站、直门达站1956~2012年年径流量均呈显著增加趋势。沱沱河站年径流在1997年发生突变,直门达站在1961和1967年发生突变。沱沱河站年径流存在20-28年、12年的显著周期。直门达站年径流存在8年、24-28年的显著周期。长江源径流与降水、气温呈显著正相关,与水面蒸发呈显著负相关。降水是三江源径流的主要来源,沱沱河径流组成中冰川消融量占比站较直门达站大。  相似文献   

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食品营养学课程思政将打破思政课程孤军作战的态势,充分利用课程本身思政元素丰富的优势,弥补思政课程理论性较强、吸引力不足的缺陷,增强课堂亲和力和感染力。食品营养学所蕴含的丰富思政元素为课程思政提供了良好的可行性,食品营养学课程思政势在必行。课程思政元素在融合过程中应尊重课程本身的属性和规律,讲究融合的技巧和策略,从而达到较好的思政效果。  相似文献   

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A great number of experiments show that pearlitic steel with Layer Meso-structure depend greatly on its struc- ture. Its fatigue life is marked influenced by the interlamellar spacing. Based on the finite element analysis of single pearlitic colony with different interlamellar spacings, the reason of the interlamellar spacing is investigated, which plays an important role in the mechanics behavior of single pearlitic colony. It is necessary to establish the relationship between the microstructure and the mechanics behavior of the pearlitic material, and the importance of the interlamellar spacing is introduced into the constitutive equation of Single Pearlitic Colony.  相似文献   

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Partial functional differential equations come from many mathematical models in physics,biology,engineering and other fields,which have strongly practical background.The oscillation theory is the one of the important branches of qualitative theory of partial functional differential equations. Therefore,it is of great theoretical and practical value to research the oscillation of partial functional differential equations.The anthors study the oscillation of the systems of a class of high order nonlinear delay partial functional differential equations.By using Green's theorem and Riccati transformation,they obtain some sufficient criteria for oscillation of all solutions of the systems under two kinds of different boundary value conditions,which are illustrated by some examples.These results offer the foundation of mathematical theory for solving the practical problems of the above fields.  相似文献   

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Calculation of the energy release rate with finite element method (FEM ) is conducted. The concrete beam model is meshed using a method without need of considering the crack-tip singular element. Two columns of nodes, which belong to the right-and left-parts of the beam, respectively, are generated on the central line of the model and released one after another in a proper sequence. Energy release rate is evaluated based on the virtual crack closure technique. Comparison between the calculated values and theoretical values is made, which shows that they are in good agreement.  相似文献   

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The prestressed tension is an important part of the prestressed concrete component construction.In order to find out the influence on the concrete hollow slab of different tension sequence,in this paper,the 30 m assembled post tensioning concrete hollow slab is simulated by the means of finite element analysis software ANSYS. The variation of the hollow slab's stress and strain are discussed according to the result of the different tensioning sequence, then, the reasonable sequence of tensioning prestressed steel wires is put forward.  相似文献   

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The mechanical model of spherical node of coal pipelines of blast furnace is built. Its boundary conditions and loads are presented. Its finite element analyses are used for this structure. Its stress distributing rules are obtained and the security of this structure is evaluated.  相似文献   

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细胞分裂素及稀土微肥在杂交水稻制种上的应用效果研究   总被引:1,自引:0,他引:1  
李国顺  徐振平 《种子》1999,(4):24-26
本文对杂交中稻岗优22制种田亲本始穗期喷施“细胞分裂表”,“稀土微肥”及“细胞分裂素”_“稀土微肥”混合液对母本穗部性状及产量等的影响进行了研究,研究结果表明:三者的明显提高母本颖花的开花数量,异交结实率,千粒重及产量,降低败育率,并优化影响结实的有关性状。  相似文献   

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掌握织金县红托竹荪中矿质元素的含量水平,通过适当调控土壤,利于红托竹荪生长,也可为红托竹荪的营养性和安全性评价提供参考依据。通过对基地土壤-红托竹荪矿质元素钾(K)、钙(Ca)、铁(Fe)、锌(Zn)、硒(Se)的测定,并对其进行相关性分析。结果表明:土壤中矿质元素平均含量大小为Fe>K>Ca>Zn>Se,红托竹荪中矿质元素平均含量从高到低依次为K>Ca>Fe>Zn>Se;富集能力最强的为钾元素;基地土壤-红托竹荪间的矿质元素相关性统计显示矿质元素Fe与土壤pH呈显著负相关(P<0.05);土壤(Ca)-红托竹荪(Ca、Zn)、土壤(Se)-红托竹荪(Se)为极显著正相关(P<0.01);土壤(K)-红托竹荪(Fe、Zn)、土壤(Fe)-红托竹荪(Fe)为显著正相关(P<0.05)。基地土壤间矿质元素的相关关系为:K-Fe、K-Se、Ca-Zn呈极显著正相关;K-Ca、Ca-Se在0.05水平上呈显著正相关;Ca-Fe、K-Fe呈极显著负相关。红托竹荪中矿质元素K-Zn、Ca-Fe呈显著正相关;K-Ca、K-Fe、Ca-Zn呈极显著正相关。其他矿质元素则无显著相关关系。在土壤中添加一定浓度的钾、钙元素可能促进红托竹荪对其他矿质元素的吸收,一定程度上可能提高竹荪的品质。  相似文献   

18.
稀土元素对酸雨胁迫小麦活性氧清除系统响应的作用   总被引:30,自引:0,他引:30  
盆栽条件下,就酸雨胁迫下小麦活性氧清除系统的响应及稀土元素作用进行了研究。结果表明:酸雨导致小麦活性氧酶促系统的SOD, CAT, POD酶活性总体水平发生变化。CAT, SOD活性减弱,POD活性增加,致使体内活性氧清除能力减弱,稀土元素的施用增加了CAT, SOD活性水平,削弱了由于酸雨胁迫所导致的POD活性的增加,从而增强了清  相似文献   

19.
青藏高原龙胆科植物花中微量元素化学计量学研究   总被引:1,自引:1,他引:0  
综合评价青藏高原龙胆科植物花中6种微量元素。采用因子分析和聚类分析方法对青藏高原龙胆科植物花中的微量元素含量数据进行分析,找出了龙胆科植物花中Ca、Mg、Cu、Fe、Mn、Zn等6种微量元素之间的关系,运用化学计量学方法,结合MATLAB2010软件,对青藏高原龙胆科植物花中微量元素和中药功效进行研究。第一公共因子F1在指标Cu、Fe、Mn上有较大的载荷,第二公共因子F2在指标Ca、Mg上有较大的载荷,第三公共因子F3在指标Zn上有较大的载荷。青藏高原龙胆科植物花中6种微量元素含量高低顺序为:麻花秦艽花>云雾龙胆花>线性龙胆花>蓝玉簪龙胆花>黄管秦艽花>管花秦艽花。该研究为大规模合理开发青藏高原龙胆科植物花资源,以及为青藏高原龙胆科植物花的药物功效学和微量元素的研究提供科学的依据和理论基础。  相似文献   

20.
李渝  魏朝富 《中国农学通报》2007,23(12):356-356
选取三峡库区万州段具有代表性母岩和土壤作为研究样点,测定了土壤和母岩中Si、Al、Fe、K、Mg、Ca、Na等几种风化成土元素的含量,探讨了土壤元素分布特征及其发生学意义。研究表明:母岩元素平均含量顺序为:Si> Al> Fe> K>Mg> Ca> Na,其中Fe、Ca、Mg、Na、K高于中国和世界元素背景值,而Al介于中国和世界元素背景值之间,Si的平均含量则低于背景值;灰岩区上的土壤中,Ca、Mg、K元素最高,砂岩母质区的土壤风化素含量较低;而碎屑岩类中,泥岩区土壤风化元素相对较高,粉砂岩区土壤风化元素含量介于泥岩与砂岩区之间;母岩的淋失强度为Ca>Mg>Al>Si>K>Fe>Na,Na元素的迁移程度小,是由于母岩中Na元素对土壤的不断补充。因此以土壤中风化元素含量为基础计算的风化指标,难以反映亚热带温暖潮湿地区的成土风化过程,常用的土壤分子硅铝率和硅铁铝率也不能指示所有土壤的风化成土作用程度,只适用于判断风化初期或成土作用早期。  相似文献   

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