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51.
This paper introduces the modeling of Unified Modeling Language with use case diagram and active diagram based on Rational Unified Process for Equipment Managemet Information System. It discusses the modeling mechanism and character of UML and develops the Computer Equipment management Information System Based Web using Rational Rose of UML CASE Tool. First, it is describe the authors how to analyze the structure of organize and build the model of structure organize. Second, they abstract the workflow of main operation in organize and build workflow model by active diagram. Finally, they abstract actor, use case with case diagram and finish the requirement model.  相似文献   
52.
为得出直墙拱形巷道围岩应力分布规律,应用复变函数弹性理论推导了直墙拱形巷道围岩应力分布的解析表达式。对直墙拱形巷道边界的围岩应力和巷道水平线方向的围岩应力分布规律进行分析,并考虑直墙拱形巷道断面高宽比和侧压系数对其影响规律。研究表明:在不同巷道断面高宽比、侧压系数下,直墙拱形巷道围岩应力集中区域主要集中在直墙底部底角处、拱形顶板中点附近和底板中部3个位置。不同巷道断面高宽比下,直墙拱形巷道沿水平线的应力分布规律基本相同。侧压系数大于1时,采用巷道断面高宽比小于1较有利于巷道稳定;侧压系数小于等于1时,采用巷道断面高宽比大于1较有利于巷道稳定。  相似文献   
53.
不同光照条件下番茄主要性状的变化及相关分析   总被引:5,自引:1,他引:5  
耐弱光性不同的番茄品种(品系)对光照条件反应不同,确定番茄耐弱光鉴定指标,可以快速有效地从大量种质资源中筛选耐弱光的番茄品种,提高品种耐弱光选择效率;试验对耐弱光性不同的4份番茄品种(品系)于定植后进行遮光处理,分别研究各品种在不同光照下的光合特性、经济性状的变化,并对11个性状进行相关及通径分析。试验结果表明,在透光率为25%(平均光照强度的光通量约为230μmol/)的光照条件下,净光合速率、气孔导度、蒸腾速率、坐果率、单果重、单株产量均有不同程度的下降,且弱光下坐果率、弱光下净光合速率、弱光下胞间CO2浓度与相对单株产量直接通径系数分别为1.92、1.76、2.13,相关系数分别为0.53、-0.09、0.48。可见,弱光下的坐果率是鉴定番茄耐弱光性的可靠指标,弱光下净光合速率和胞间CO2浓度可作为耐弱光性鉴定的重要辅助指标。  相似文献   
54.
煤水浆(CWM)是一种新型的正在开发的可工业化的石油代用燃料。而将煤水浆用于柴油机则处于试验阶段。流变特性是煤水浆性质判定的主要依据之一。本文将就下列三方面对超细煤木浆与柴油组成的混合液(用作柴油机燃料)的流变特性进行分析:(1)流变模型和流变参量;(2)超细煤水浆与柴油的最佳混合比;(3)触变性。  相似文献   
55.
Intercropping, drip irrigation, and the use of plastic mulch are important management practices, which can, when utilized simultaneously, increase crop production and save irrigation water. Investigating soil water dynamics in the root zone of the intercropping field under such conditions is essential in order to understand the combined effects of these practices and to promote their wider use. However, not much work has been done to investigate soil water dynamics in the root zone of drip-irrigated, strip intercropping fields under plastic mulch. Three field experiments with different irrigation treatments (high T1, moderate T2, and low T3) were conducted to evaluate soil water contents (SWC) at different locations, for different irrigation treatments, and with respect to dripper lines and plants (corn and tomatoes). Experimental data were then used to calibrate the HYDRUS (2D/3D) model. Comparison between experimental data and model simulations showed that HYDRUS (2D/3D) described different irrigation events and SWC in the root zone well, with average relative errors of 10.8, 9.5, and 11.6 % for irrigation treatments T1, T2, and T3, respectively, and with corresponding root mean square errors of 0.043, 0.035, and 0.040 cm3 cm?3, respectively. The results showed that the SWC in the shallow root zone (0–40 cm) was lower under non-mulched locations than under mulched locations, irrespective of the irrigation treatment, while no significant differences in the SWC were observed in the deeper root zone (40–100 cm). The SWC in the shallow root zone was significantly higher for the high irrigation treatment (T1) than for the low irrigation treatment, while, again, no differences were observed in the deeper root zone. Simulations of two-dimensional SWC distributions revealed that the low irrigation treatment (T3) produced serious severe water stress (with SWCs near the wilting point) in the 30–40 cm part of the root zone, and that using separate drip emitter lines for each crop is well suited for producing the optimal soil water distribution pattern in the root zone of the intercropping field. The results of this study can be very useful in designing an optimal irrigation plan for intercropped fields.  相似文献   
56.
以铁皮石斛商品瓶苗和盆栽苗茎段为试材,添加不同浓度6-BA、NAA,诱导茎段腋芽、原球茎和不定根,建立再生体系,快速繁殖铁皮石斛组培苗,以期为秦岭淮河一线以北地区人工繁殖铁皮石斛提供参考依据。结果表明:外植体宜采用70%酒精浸泡20 s,0.1%升汞浸泡8 min消毒;MS+6-BA 3.0~5.0 mg·L^-1+NAA 0.1~1.0 mg·L^-1适合腋芽分化和增殖,分化率92%~100%;1/2MS+6-BA 2.0 mg·L^-1+NAA 0.5 mg·L^-1+土豆泥15%适合原球茎诱导增殖,增殖倍数7.7;1/2MS+NAA 0.3 mg·L^-1生根率为100%;以松针土移栽,成活率83%。  相似文献   
57.
58.
Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1)to identify key factors affecting the elongation of basal internodes and(2)to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha−1 in early season and 0,90,and 180 kg N ha−1 in late season)as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m−2)as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV)and final length of second internode(counted from soil surface upward)(FIL)were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P<0.01)and positively correlated with LAI(P<0.01),but not correlated with NLV(P>0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lb and LAI(R2=0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lb and LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice.  相似文献   
59.
60.
为了明确微波辐照对全麦粉储藏稳定性及品质的影响,通过对全麦粉进行不同微波功率和不同微波时间处理,分析了全麦粉储藏过程中菌落总数以及脂肪酸值、面团流变学特性和馒头品质的变化。结果表明,随着微波功率的增加和处理时间的延长,全麦粉脂肪酸值和菌落总数增加速率得到抑制;湿面筋含量、面团稳定时间先增加后降低;气体释放曲线的最大高度(H′_m)和产气量(R_1)逐渐增加,气体保留体积(R_2)先增加后降低,发酵性能得到改善;馒头比体积与综合评分先增加后降低。当微波辐照功率为400 W、处理时间为120 s时,全麦粉可以更好储藏,同时全麦粉面团的粉质特性、流变发酵特性及馒头的品质得到改善。  相似文献   
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