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当年种葱当年收 缩短周期产量高
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作者 张国斌 隋遵义 何洪千 《农村实用科技信息》 1996年第6期8-8,共1页
大葱是北方人民喜食的"三辣"蔬菜之一,无论城市居民还是农村百姓普遍食用。因此发展大葱生产,既能满足城乡人民对蔬菜的需求,又能为农民致富创出一条新路。大葱为两年生蔬菜.生长周期可达21—22个月,能不能将周期缩短到7个月... 大葱是北方人民喜食的"三辣"蔬菜之一,无论城市居民还是农村百姓普遍食用。因此发展大葱生产,既能满足城乡人民对蔬菜的需求,又能为农民致富创出一条新路。大葱为两年生蔬菜.生长周期可达21—22个月,能不能将周期缩短到7个月,即当年葱当年收。经过95年在朝阳开发区试验结果,证明当年葱完全可以当年收。平均葱高1米以上,最高者达1.38米,最大株重1.2斤,95年栽当年葱0.3亩,收大葱3382斤,合亩产鲜葱11,273斤。 展开更多
关键词 大葱 蔬菜 城市居民 生长周期 开发区 农民致富 试验结果 北方人 缩短 周期产量
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棉花产量周期及丰产年预测的研究
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作者 刘仕英 赵星 周艳初 《农业系统科学与综合研究》 CSCD 北大核心 1995年第3期198-200,共3页
以湖南省常德市1954~1989年的棉产量数据为依据,运用谐波分析方法似合了棉花的产量周期规律,并对常德市未来的棉花丰产年进行了预测。结果表明,棉花产量的周期有4年、9年和18年,但基本周期是4年左右,这与实际的棉花产量情况基本相符;... 以湖南省常德市1954~1989年的棉产量数据为依据,运用谐波分析方法似合了棉花的产量周期规律,并对常德市未来的棉花丰产年进行了预测。结果表明,棉花产量的周期有4年、9年和18年,但基本周期是4年左右,这与实际的棉花产量情况基本相符;依据棉花产量的周期规律,预测1990年和1995年是常德的棉花丰产年。 展开更多
关键词 棉花 谐波分析 产量周期
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利用周期性产量变化进行试井分析来描述油藏
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作者 陈兰 《四川石油普查》 2000年第1期70-82,共13页
这项研究是探讨一下通过解释周期性产量变化的压力响应来描述一些区域上非均质储层中渗透率分布的可能性。在具有连续和平滑变化的径向渗透率分布的油藏中,由正统型产量引起的压力动态,我们用一个数学模型加以说明。通过应用有规律的... 这项研究是探讨一下通过解释周期性产量变化的压力响应来描述一些区域上非均质储层中渗透率分布的可能性。在具有连续和平滑变化的径向渗透率分布的油藏中,由正统型产量引起的压力动态,我们用一个数学模型加以说明。通过应用有规律的扰动分析获得了该数学模型的解,并建立了周期影响的半径与正统产量频率之间的相关关系。该模型的分析扰动解使得我们能够对油藏的区域非均质性对工作井或是观察井压力响应的影响进行定量评估。 展开更多
关键词 周期产量 产量变化 渗透率 试井分析 油藏描述
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作物产量的双重分析预报模型
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作者 李邦宪 朱敏 《浙江气象》 1991年第2期28-31,共4页
一、引言在作物产量的气象预测预报模型中,通常是将作物产量y分解为三个部分:由相对稳定的惰性少变因子(主要是指农业技术水平)引起的趋势产量y_t,它一般表现为产量的正函数;二是由不稳定的活跃多变因子(主要是指气象条件)引起的气象产... 一、引言在作物产量的气象预测预报模型中,通常是将作物产量y分解为三个部分:由相对稳定的惰性少变因子(主要是指农业技术水平)引起的趋势产量y_t,它一般表现为产量的正函数;二是由不稳定的活跃多变因子(主要是指气象条件)引起的气象产量y_w,在人们尚无法控制和改变大自然的情况下,它总是使得实际产量沿时间趋势线上下波动; 展开更多
关键词 作物产量 预报模型 气象预测 农业技术水平 正函数 周期产量 趋势线 气象条件 时间序列 水稻生长期
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埃克森美孚和雪佛龙并购独立石油公司的交易分析与启示
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作者 周静 《天然气与石油》 2024年第2期117-124,共8页
2023年10月11日,埃克森美孚(ExxonMobil)宣布并购先锋自然资源(Pioneer Natural Resources),10月23日雪佛龙(Chevron)宣布并购赫斯(Hess),两笔交易充分体现了大型跨国石油公司聚焦油气勘探开发业务实现持续盈利增长的战略思维,以及立足... 2023年10月11日,埃克森美孚(ExxonMobil)宣布并购先锋自然资源(Pioneer Natural Resources),10月23日雪佛龙(Chevron)宣布并购赫斯(Hess),两笔交易充分体现了大型跨国石油公司聚焦油气勘探开发业务实现持续盈利增长的战略思维,以及立足既有业务并优选目标的并购策略。战略上,交易买方明晰油气生产商定位;策略上,依托并购做实未来增产基础。两笔并购交易均采用“全股票”对价支付方式,可有效降低运营成本和融资负担,交易双方主要机构投资者也呈现较高一致性。若顺利交割,埃克森美孚进一步夯实美国二叠盆地致密油资产,成为致密油领导者,利用短周期产量增强供应灵活性;雪佛龙则新增圭亚那世界级项目,在优化全球资产布局的同时,占据深水资源领先地位。结合分析结果,建议中国石油公司坚持价值理念,以战略思维完善海外业务发展顶层设计;注重策略活力,以创新思维探索特色国际油气合作模式;构建韧性组合,以系统思维评价海外油气项目投资机会。 展开更多
关键词 石油公司 并购 页岩油气 周期产量 韧性
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关于中国铅的资源效率研究 被引量:16
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作者 毛建素 陆钟武 《环境科学研究》 EI CAS CSCD 北大核心 2004年第3期78-80,共3页
引入铅的资源效率的概念。通过分析铅生产过程中铅的流动方向和数量,获得了铅的资源效率变化规律:铅的资源效率与铅的循环率、排放率、生命周期产量比有关。根据统计数据,估算了1990—2000年铅的资源效率平均值只有0 91t t。通过估算这... 引入铅的资源效率的概念。通过分析铅生产过程中铅的流动方向和数量,获得了铅的资源效率变化规律:铅的资源效率与铅的循环率、排放率、生命周期产量比有关。根据统计数据,估算了1990—2000年铅的资源效率平均值只有0 91t t。通过估算这一时期铅的循环率、排放率、生命周期产量比的实际数值,判定了中国铅的资源效率低下的原因:铅的循环状况较差,废铅排放严重,铅的年产量高速增长。最后,提出了现阶段改进的几点建议。 展开更多
关键词 资源效率 循环率 排放率 生命周期产量
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锦27-031-313井堵水复产建议及效果分析
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作者 陈永刚 《内蒙古石油化工》 CAS 2012年第9期155-156,共2页
针对稠油藏井锦27-031-313因套变导致该井高含水停产,严重影响周期生产效果的问题,通过分析并实施堵水地质增产措施有效提高了热采周期产量,堵水复产累计增油2169t,取得较好的措施效果。锦27-031-313井堵水措施成功经验对其它因套变落... 针对稠油藏井锦27-031-313因套变导致该井高含水停产,严重影响周期生产效果的问题,通过分析并实施堵水地质增产措施有效提高了热采周期产量,堵水复产累计增油2169t,取得较好的措施效果。锦27-031-313井堵水措施成功经验对其它因套变落物等井况影响采出程度较低油井进一步提高开发效果具有重要借鉴作用。 展开更多
关键词 边底水油藏 高含水 套变 堵水措施 周期产量
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分支水平井技术在薄层超稠油中的应用
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作者 李志龙 《内蒙古石油化工》 CAS 2011年第7期180-182,共3页
针对超稠油油藏锦25-32-26断块于楼油层由于原油粘度高、油层薄而导致直井蒸汽吞吐效果较差的问题,通过部署分支水平井并结合二氧化碳吞吐、高温降粘等配套工艺增产措施有效提高了热采周期产量,与直井相比平均周期产量由228t提高到625t... 针对超稠油油藏锦25-32-26断块于楼油层由于原油粘度高、油层薄而导致直井蒸汽吞吐效果较差的问题,通过部署分支水平井并结合二氧化碳吞吐、高温降粘等配套工艺增产措施有效提高了热采周期产量,与直井相比平均周期产量由228t提高到625t,取得较好的吞吐效果。锦25-32-26块分支水平井成功经验对其它薄层稠油、超稠油油藏进一步提高吞吐开发效果具有重要借鉴作用。 展开更多
关键词 超稠油 分支水平井 二氧化碳吞吐 高温降粘 热采周期产量
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单家寺油田稠油热采经济评价
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作者 陈福星 《胜利油田党校学报》 1987年第1期17-20,共4页
单家寺油田稠油热采试验区,采用注蒸汽采油,收到明显效果。 胜利油田稠油资源丰富,地质储量达5亿吨以上,其中已探明储量3.8亿吨(已动用2亿吨,未动用1.8亿吨)。从全国来看,稠油储量更为可观。
关键词 稠油热采 单家 稠油资源 注蒸汽 蒸汽驱 投资利润率 经济评价 周期产量 注入速度 蒸汽吞吐
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Comparative Analysis of Energy Efficiency in Wheat Production in Different Climate Conditions of Europe
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作者 Janusz Gotaszewski Marcel van der Voort +3 位作者 Andreas Meyer-Aurich Fatima Baptista Athanasios Balafoutis Hannu Juhani Mikkola 《Journal of Agricultural Science and Technology(B)》 2014年第8期632-640,共9页
This paper presents results concerning energy efficiency of wheat production considered in the context of specific energy input variation in different climatic conditions of Europe as well as case studies on implement... This paper presents results concerning energy efficiency of wheat production considered in the context of specific energy input variation in different climatic conditions of Europe as well as case studies on implementation of selected energy saving measures in practice. The source data collected from the six european union (EU) countries represent five agricultural regions of continental Europe and three climates: continental, temperate and Mediterranean. The life cycle assessment (LCA) methodology was applied to analyze the data excluding of pre-farm gate activities. The total primary energy consumption was decomposed into main energy input streams and it was regressed to yield. In order to compare energy efficiency of wheat production across the geographical areas, the data envelopment analysis (DEA) was applied. It was shown that the highest wheat yield (6.7 t/ha to 8.7 t/ha) at the lowest specific energy input (2.08 GJ/t to 2.56 G J/t) is unique for temperate climate conditions. The yield in continental and Mediterranean climatic conditions is on average lower by 1.3 t/ha and 2.7 t/ha and energy efficiency lower by 14% and 38%, respectively. The case studies have shown that the energy saving activities in wheat production may be universal for the climatic zones or specific for a given geographical location. It was stated that trade-offs between energy, economic, and environmental effects, which are associated with implementation of a given energy saving measure or a set of measures to a great extent depend on the current energy efficiency status of the farm and opportunity for investment, which varies substantially across Europe. 展开更多
关键词 WHEAT energy efficiency trade-off analysis
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An Integrated Approach for Decision Support through Multi-objective Optimization with Application to an Ill-posed Design Problem
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作者 Yoshiaki Shimizu Yasumasa Kato Takeshi Kariyahara 《Computer Technology and Application》 2011年第11期912-925,共14页
In the current scenario of global competition and short product life cycles, customer-defined satisfaction has attracted interest in artifact design. Accordingly, intelligent decision-making through multi-objective op... In the current scenario of global competition and short product life cycles, customer-defined satisfaction has attracted interest in artifact design. Accordingly, intelligent decision-making through multi-objective optimization has been proposed as an efficient method for human-centered manufacturing. However, previous vast researches on optimization have been mainly focused on optimization theory and optimization techniques and paid little interests on the process of problem formulation itself. In this paper, therefore, the authors present a total framework for supporting multi-objective decision making. Then, the authors try to solve the formulated multi-objective optimization problem that involves both qualitative and quantitative performance measures as a general consequence from the above procedure. Taking especially quality as a qualitative measure, the authors gave a new idea to evaluate the quality quantitatively. Additionally, to facilitate the portability of the proposed method in multidisciplinary decision-making environments, the authors implement the proposal algorithm in an Excel spreadsheet and validate the effectiveness of the approach through a case study. 展开更多
关键词 Integrated systems approach optimization engineering multi-objective optimization META-MODELING value system design.
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Concept of Integrated Waste Management as Recoverable Resources in Product Cycle
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作者 Aleksandr Telizhenko Vadym Lukianykhin +4 位作者 Sergey Kuzmenko Elena Lukianykhina Elena Vishnitskaya Min Li Tatyana Shevchenko 《Journal of Environmental Science and Engineering(B)》 2012年第3期312-323,共12页
This paper presents a conceptual framework of integrated waste management which focuses on all stages of product life cycle. A mechanism of resource recovery motivating from waste in economic system (designers, produ... This paper presents a conceptual framework of integrated waste management which focuses on all stages of product life cycle. A mechanism of resource recovery motivating from waste in economic system (designers, producers, consumers, stakeholders in the field of disposal of the product) is suggested. The classification of institutional and economic instruments in the field of waste management as recoverable resources is developed. The author has proposed a scientific and methodical approach to the formation of an integrated waste management as recoverable resources, which is based on a set of methods of economic incentives at all stages of product life cycle and ensures the maximum possible and the environmentally safe management of wastes containing valuable resource components. 展开更多
关键词 WASTE recoverable resources integrated waste management product life cycle organizational-economic mechanism.
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Life Cycle Input-Output Analysis Extended to Use, Disposal, and Recycling Stages Applied to Embodied CO2 Emissions of a Refrigerator
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作者 Yuki Mizumoto Yohji Uchiyama Keiichi Okajima 《Journal of Energy and Power Engineering》 2013年第4期695-704,共10页
Input-output analysis is widely employed to analyze inventories of a product's embodied energy and environmental burdens. However, input-output analysis focuses only on the production stage and ignores other life cyc... Input-output analysis is widely employed to analyze inventories of a product's embodied energy and environmental burdens. However, input-output analysis focuses only on the production stage and ignores other life cycle phases. Input-output analysis is not exactly a LCA (life cycle assessment) method in the strict sense of ISO 14040 standards, which must cover all stages of a product's life cycle, "from the cradle to the grave", so to speak. A tiered hybrid LCA is a useful tool that covers all life cycle stages by combining a process analysis with the input-output analysis method. This study aims to extend input-output analysis to the use, disposal, and recycling stages by using matrix-based method. The new method is applied to the analysis of the embodied CO2 emissions of a refrigerator as a case study. The entire life cycle C02 emissions are estimated to be 2.9 tons, including indirect emissions, and the reduction in CO2 emissions due to recycling steel scrap is calculated as 48.5 kg. The authors conclude that the new method enables a consistent inventory analysis for all life cycle stages by combining process and input-output methods. 展开更多
关键词 Input-output analysis matrix-based method hybrid lifecycle analysis RECYCLING REFRIGERATOR CO2 emission.
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