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171.
根据传统木家具制造车间产品种类复杂、信息处理不够流畅、生产过程不够规范的现状,提出利用MES系统对木家具制造车间进行数字化计划排产。利用MES系统的应用优势,在信息互通流畅、合理安排生产、充分提高产能等方面对传统家具制造车间进行改造,达到提高企业的生产效率,降低生产成本的目的。通过一系列的技术应用,MES系统将有效地对传统木家具制造车间进行管理优化,为企业的产业升级作出巨大贡献。  相似文献   
172.
中转油库作为成品油管网系统的重要节点,影响着整个系统的批次调度计划。为保证油库与管道协调运行,必须综合各方面因素来制定油库的调度计划。针对中转油库调度优化问题,基于研究时间内收发油计划、油库信息等数据,考虑油罐下载、外输、倒罐、检修等操作,以油罐切换费用和收发油蒸发损耗费用之和最小为目标函数,建立混合整数线性规划(MILP)模型,并以某真实油库为例,求解得到该油库各油罐的详细调度计划。计算结果表明:该模型准确性较高、实用性较好,可以为中转油库调度计划的制定提供指导。(图3,表4,参20)  相似文献   
173.
双罐区的成品油管网中转油库在油罐收发油作业时,既要满足管网运行要求,又要满足罐区与油罐作业工艺流程的复杂要求,导致油罐收发油作业计划难度较大。针对给定的成品油管网批次计划,提出了一种编制双罐区中转油库油罐收、发油计划的时序递推法:通过引入罐容上限、罐容下限、油罐作业连续性、罐区作业连续性、油品沉降时间等经验规则,对罐区与油罐划分优先级,在每个时段均可选择出最合适的油罐来进行收、发油作业,确定整个计划期内任意时刻中转油库各油罐的状态(收油、发油或静置)和收油/发油流量。将该方法应用于某成品油管网的一个双罐区中转油库,验证了方法的可行性与实用性。基于该方法开发的计算机软件可以作为成品油管网双罐区中转油库油罐收、发油计划编制的有效工具。  相似文献   
174.
吴婕 《节水灌溉》2019,(5):46-50,56
通过在疏勒河流域玉门市进行色素辣椒田间试验,分析不同灌水量对辣椒全生育期生长指标、品质、干物质积累的影响,研究全生育期耗水特性,综合考虑产量、水分利用效率等各项指标,提出疏勒河流域最适宜灌溉制度。结果表明:坐果期株高是开花期的3.2倍,坐果期叶面积系数是开花期的5.6倍,开花期至坐果期是辣椒株高、叶面积增速最大期;从坐果期到膨大期,辣椒器官存储的营养成分逐渐向果实移动,果实干重与整株干重的比值逐渐增大,干物质平均增加了22.88g,占整个生育期干物质总量的50%以上;不同灌水量对辣椒营养品质影响差异显著,其中DG2相比其他处理显著提高辣椒品质,较对照CK分别显著提高3.61%、3.90%、13.88%、29.76%;全生育期耗水量呈现由低到高再降低的变化趋势,开花期耗水模数最大,坐果期耗水强度最大,开花期、坐果期和膨大期3个生育期的耗水量占全生育期耗水量比例达60%以上,此时是辣椒对水分最敏感的时期,应保证辣椒正常生长所需的水分和养分要求;综合辣椒产量和水分生产效率考虑,提出全生育期灌水9次、灌溉定额3540m^3/hm^2为疏勒河流域辣椒膜下滴灌的最适宜灌溉制度。  相似文献   
175.
Rational irrigation scheduling based on sensing drought stress directly in plants is becoming more important due to increasing worldwide scarcity of fresh water supplies. In order to evaluate a set of potential biochemical and physiological stress indicators and select the best drought stress markers in apple trees, two experiments with potted trees and an experiment with intensive orchard grown apple trees ‘Elstar’ and ‘Jonagold Wilmuta’ were conducted in early summer in tree following years. Biochemical parameters: ascorbic acid, glutathione, tocopherols, chlorophylls, carotenoids, free amino acids, soluble carbohydrates, and physiological parameters already known as stress indicators in apple trees: predawn and midday leaf water potential, net photosynthesis (Pn), stomatal conductance (gs), transpiration (Tr) and intercellular CO2 concentration (Ci) were measured in leaves of apple trees subjected to different intensities of slowly progressing drought or no drought. Our study pointed out zeaxanthin and glutathione as the best drought stress markers in apple trees. Ascorbate and sorbitol appeared to be reliable indicators of moderate drought only. Responses of other tested biochemical parameters were not consistent enough to prove their role as drought stress markers in apple trees. Relative air humidity should be taken in consideration when physiological parameters gs, Pn, Tr and Ci are used as drought stress markers in apple trees. Our study revealed that in situations where low relative air humidity affects gs and with gs connected physiological parameters, biochemical markers may be better tool for determination of drought stress intensities in apple trees.  相似文献   
176.
Integrated approaches to forest planning lead to large models and there is a subsequent need for a reduction of the number of constraints and variables. One way of achieving this is to aggregate data, either spatially or temporally. In this paper an integrated forest planning mixed integer model that takes into account both long-term strategic and shorter-term tactical forest management decisions is utilised. The study analyses the consequences of temporal aggregation in the strategic part of the integrated model, whereas the tactical part is modelled by a fixed set of years divided into seasons. For reference, analyses are also made using a pure strategic linear programming model. Cases using both equal and variable strategic period lengths are presented, and two case study areas are used. Results indicate that integrated plans, as well as strategic plans, are not particularly affected by the number of equal length strategic periods when more than five periods, i.e. less than 20 year period length, are used. When modelling strategic and integrated problems using variable-length periods, care should be taken to ensure that harvest operations late in the planning horizon get enough timing options to be adequately described.  相似文献   
177.
In the past studies on the Gentan probability theory, economic factors, such as the price of logs and the interest rate, have not been embedded into the derived stochastic model due to the limitation of the underlying assumptions. This has lead to misleading results of economic analysis for harvesting behavior based on the Gentan probability theory. In this paper, economic analysis of harvesting behavior was conducted by extending the Gentan probability theory. Since the proposed stochastic process can incorporate a nonstationary growth function, economic analysis of harvesting behavior was easily implemented. Experimental analysis of economic factors showed that change in the price of logs, the interest rate and harvest related costs affected the Gentan probability distribution. Although the analysis is still hypothetical, the results imply the potential use of the Gentan probability theory to predict the forest owners' harvesting behavior.  相似文献   
178.
颜丽 《农机化研究》2022,44(1):237-241
为了实现在多农机作业时农机管理人员对农机的调度和指挥,实现远程作业状态的监测,将英语交互式音视频学习平台技术引入到了农机远程系统的设计上,并采用网状无线网络结构构建了远程无线通信网络.为了提高远程作业端传送到控制端的视频的质量,利用图像融合处理算法对视频图像进行了处理,得到了较高质量的视频.以多联合收割机的作业为例,对...  相似文献   
179.
Pomegranate (Punica granatum L.) is a drought-hardy crop, suited to arid and semi-arid regions, where the use of marginal water for agriculture is on the rise. The use of saline water in irrigation affects various biochemical processes. For a number of crops, yields have been shown to decrease linearly with evapotranspiration (ET) when grown in salt-stressed environments. In the case of pomegranate, little research has been conducted regarding the effect of salt stress. Our study focused on the responses of ET, crop coefficient (Kc) and growth in pomegranate irrigated with saline water. Experiments were conducted using lysimeters with two varieties of pomegranate, P. granatum L. vars. Wonderful and SP-2. The plants were grown with irrigation water having an electrical conductivity (ECiw) of 0.8, 1.4, 3.3, 4.8 and 8 dS m−1. Plants were irrigated with 120% of average lysimeter-measured ET. Seasonal variation in ET, crop coefficient (Kc) and growth were recorded. Variation in daily ET was observed 1 month after initiation of the treatments. While significant seasonal ET variation was observed for the EC-0.8 treatment, it remained more stable for the EC-8 treatment. Salinity treatment had a significant effect on both daily ET (F = 131, p < 0.01) and total ET (F = 112.68, p = 0.001). Furthermore, the electrical conductivity of the drainage water (ECdw) in the EC-8 treatment was five times higher than that of the EC-0.8 treatment in the peak season. Fitting the relative ET (ETr) to the Maas and Hoffman salinity yield response function showed a 10% decrease in ET per unit increase in electrical conductivity of the saturated paste extract (ECe) with a threshold of 1 dS m−1. If these parameters hold true in the case of mature pomegranate trees, the pomegranate should be listed as a moderately sensitive crop rather than a moderately tolerant one. Fitting 30-day interval ETr data to the Maas and Hoffman salinity yield response function showed a reduction in the slope as the season progressed. Thus using a constant slope in various models is questionable when studying crop-salinity interactions. In addition, both of the varieties showed similar responses under salt stress. Moreover, the calculated value of Kc is applicable for irrigation scheduling in young pomegranate orchards using irrigation water with various salinities.  相似文献   
180.
The effects of high crop load (unthinned trees, 22-23 fruits cm−2 of trunk cross-sectional area (TCSA)), commercial crop load (3-4 fruits cm−2 of TCSA), and no crop load (all fruitlets removed) on maximum daily trunk shrinkage (MDS), trunk growth rate (TGR) and stem water potential (Ψstem) were studied during the fruit growth period and 20 days following harvest in fully irrigated early maturing peach trees, Prunus persica (L.) Batsch, cv. Flordastar. Even though crop load did not affect plant water status, the MDS and TGR values increased and decreased, respectively, as a result of the crop load effect. In this sense, for the same Ψstem value, there was a linear increase in MDS with crop load, with a slope of 6.6 μm MPa−1 per unit of crop load increment. The effects of environmental conditions on daily MDS values were also dependent on crop load, suggesting that MDS reference values should be obtained by representing the relations between MDS and the climatic variables (daily mean air temperature, daily mean vapour pressure deficit and daily crop reference evapotranspiration) for a given crop load. The constancy of the relation between MDS and Ψstem across crop load underlined the constancy of the elastic properties of the bark tissues.  相似文献   
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