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Long-term simulation of growth stage-based irrigation scheduling in maize under various water constraints

Quanxiao FANG, Liwang MA, Lajpat Rai AHUJA, Thomas James TROUT, Robert Wayne MALONE, Huihui ZHANG, Dongwei GUI, Qiang YU

《农业科学与工程前沿（英文）》 2017年第4卷第2期页码 172-184 doi: 10.15302/J-FASE-2017139

摘要： Due to varying crop responses to water stress at different growth stages, scheduling irrigation is a challenge for farmers, especially when water availability varies on a monthly, seasonal and yearly basis. The objective of this study was to optimize irrigation between the vegetative (V) and reproductive (R) phases of maize under different available water levels in Colorado. Long-term (1992–2013) scenarios simulated with the calibrated Root Zone Water Quality Model were designed to meet 40%–100% of crop evapotranspiration (ET) requirements at V and R phases, subject to seasonal water availabilities (300, 400, 500 mm, and no water limit), with and without monthly limits (total of 112 scenarios). The most suitable irrigation between V and R phases of maize was identified as 60/100, 80/100, and 100/100 of crop ET requirement for the 300, 400, 500 mm water available, respectively, based on the simulations from 1992 to 2013. When a monthly water limit was imposed, the corresponding suitable irrigation targets between V and R stages were 60/100, 100/100, and 100/100 of crop ET requirement for the above three seasonal water availabilities, respectively. Irrigation targets for producing higher crop yield with reduced risk of poor yield were discussed for projected five-year water availabilities.

关键词： RZWQM ET-based irrigation schedule maize water constrains

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实时灌溉预报

茆智,李远华,李会昌

《中国工程科学》 2002年第4卷第5期页码 24-33

摘要：

实时灌溉预报是制定动态灌溉用水计划的基础，对灌区节水，增加作物产量和提高经济效益起着重要作用。其重点与难点内容是作物需水量实时预报。国内外已有的作物需水量预报方法与模型，是建立在历史典型水文年资料基础之上的，无法用于实时预报。文章分析了作物需水量与气象条件和非气象条件（主要是植物条件以及土壤条件）之间的关系，提出了根据天气类型、作物绿叶覆盖率和土壤有效含水率3项因素进行作物需水量实时预报的方法与模型，介绍了具体的预报步骤与计算框图，改进了常规的预报方法，主要是用预报的天气类型（晴、昙、阴、雨）代替修正彭曼法中所需的气温、空气湿度、日照时数与风速4项气象因素，用绿叶覆盖率代替叶面积指数，并提出了新的计算土壤水分修正系数的数学模型。

关键词：灌溉实时预报作物需水量灌溉制度

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用齐夫定律解读教材词表——评Xiao et al. (2017)《基于语料库的小学英语认识率及教材选词策略研究》 Correspondence

Qiong HU, Ming YUE

《信息与电子工程前沿（英文）》 2017年第18卷第7期页码 863-866 doi: 10.1631/FITEE.1700418

摘要： Xiao et al. (2017)在对比分析4个语料库的基础上，提出国内小学六年级学生的识词率增长不能令人满意的观点，建议人教版小学英语通用教材总词汇在原有726个的基础上再增加903个，并删除twelfth

关键词：齐夫定律（Zipf’s law）；语料库；英语；教科书；词表

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et’s disease in a Chinese population

null

《医学前沿（英文）》 2012年第6卷第4期页码 354-359 doi: 10.1007/s11684-012-0234-2

摘要：

Beh?et’s disease is defined as a multisystemic inflammatory disease. Although the precise pathogenesis and etiology is still a mystery, accumulating evidence shows that genetic variants of immune-related genes have a profound influence on the development of Beh?et’s disease. To explore the genetic factors for Beh?et’s disease, our group investigated the association of Beh?et’s disease with multiple immune response genes and has identified multiple Beh?et’s disease-related immunoregulatory pathways in the Chinese Han population. A large number of gene polymorphisms were studied including STAT4, IL23R, CD40, CCR1/CCR3, STAT3, OPN, IL17, JAK2, MCP-1, CTLA4, PD-1, PD-L1, PD-L2, TGRBR3, CCR6, PTPN22, FCRL3, IRF5, SUMO4 and UBAC2. Significant associations were found between Beh?et’s disease and STAT4, IL23R, CD40, CCR1/CCR3, STAT3, MCP-1, TGFBR3, FCRL3, SUMO4, UBAC2. These genetic predisposition studies support an important role for both lymphocyte differentiation as well as ubiquitination pathways. These findings are helpful in elucidating the pathogenesis of Beh?et’s disease and hopefully will allow the development of novel treatment regimes.

关键词： Beh?et’s disease SNPs immune gene genetic study

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Oxidative stress in granulosa cells contributes to poor oocyte quality and IVF-ET outcomes in women with

Qiaohong Lai, Wenpei Xiang, Qing Li, Hanwang Zhang, Yufeng Li, Guijin Zhu, Chengliang Xiong, Lei Jin

《医学前沿（英文）》 2018年第12卷第5期页码 518-524 doi: 10.1007/s11684-017-0575-y

摘要：

The increased levels of intracellular reactive oxygen species (ROS) in granulosa cells (GCs) may affect the pregnancy results in women with polycystic ovary syndrome (PCOS). In this study, we compared thein vitro fertilization and embryo transfer (IVF-ET) results of 22 patients with PCOS and 25 patients with tubal factor infertility and detected the ROS levels in the GCs of these two groups. Results showed that the PCOS group had significantly larger follicles on the administration day for human chorionic gonadotropin than the tubal factor group (P<0.05); however, the number of retrieved oocytes was not significantly different between the two groups (P>0.05). PCOS group had slightly lower fertilization, cleavage, grade I/II embryo, clinical pregnancy, and implantation rates and higher miscarriage rate than the tubal factor group (P>0.05). We further found a significantly higher ROS level of GCs in the PCOS group than in the tubal factor group (P<0.05). The increased ROS levels in GCs caused GC apoptosis, whereas NADPH oxidase 2 (NOX2) specific inhibitors (diphenyleneiodonium and apocynin) significantly reduced the ROS production in the PCOS group. In conclusion, the increased ROS expression levels in PCOS GCs greatly induced cell apoptosis, which further affected the oocyte quality and reduced the positive IVF-ET pregnancy results of women with PCOS. NADPH oxidase pathway may be involved in the mechanism of ROS production in GCs of women with PCOS.

关键词： PCOS ROS granulosa cell IVF-ET NADPH oxidase

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基于4D CAD的大型桥梁施工进度系统仿真研究

张正峰,付金强,吴康新,张发瑜

《中国工程科学》 2006年第8卷第1期页码 63-66

摘要：

随着桥梁建设的发展，传统横道图与网络图已成为施工管理水平提高的制约因素。将面向对象的复杂工程系统仿真方法与CAD数字建模方法相结合，将桥梁的3D整体模型和施工进度相链接，提出了基于4D CAD的桥梁施工系统仿真思想，使施工过程的动态可视化与直观分析优化后的施工进度成为可能。以Visual C++作为仿真平台，设计编制了桥梁施工4D CAD可视化仿真软件。研究成果在某斜拉桥工程施工组织设计中得到成功应用，验证了基于4D CAD的大型桥梁可视化仿真方法在斜拉桥施工进度分析与优化方面的实用性和优越性。

关键词：施工进度系统仿真 4D CAD 斜拉桥

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水稻节水灌溉及其对环境的影响

茆智

《中国工程科学》 2002年第4卷第7期页码 8-16

摘要：

水稻是中国最主要的粮食作物之一，其产量约占粮食作物总产量的40%；在全国约11×108hm2的粮食作物总面积中，稻田面积约占28%。20世纪80年代以来，水稻产区的水资源短缺已成为当地农业生产中的重要问题，各地试验、开发、应用与推广了许多种水稻节水灌溉模式。文章根据这些新的水稻灌溉模式试验结果与推广经验，将我国水稻节水灌溉主要模式归纳为浅、湿、晒结合，间歇淹水，半旱栽培和蓄雨型等4类。阐述了这些模式的田间水分控制标准以及节水、增产和提高水分生产率的潜力；提出了该4类模式的选择原则以及应用这些模式时应注意的问题；分析、讨论了推广这些模式能够持续节水与提高水分生产率的机理以及对环境的影响。

关键词：水稻节水灌溉灌溉模式节水潜力环境影响

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基于工期可控性的网络进度计划仿真评价方法研究

潘菲菲,王仁超,曹永雷

《中国工程科学》 2015年第17卷第1期页码 143-150

摘要：

针对工程建设过程中常常通过资源重新配置或提高资源利用率来应对风险事件可能引起工期延迟的问题，提出了基于工期可控性的网络进度计划随机仿真评价方法，以资源配置和利用裕度作为活动的可控性衡量指标，同时考虑了风险事件发生时间不同导致的风险应对措施的可实施性不同的问题，通过对各个风险事件发生时间及其引起的活动持续时间延误、风险应对效果等进行随机仿真，从而对整个项目的工期分布进行模拟，评价编制的网络进度计划的合理性。算例表明：相对于传统的基于工期和基于因素的Monte-Carlo仿真评价方法，基于工期可控性的仿真评价方法得到的结果更为合理。

关键词：网络进度计划；随机仿真；风险应对；工期可控性；评价

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Influence of sprinkler irrigation droplet diameter, application intensity and specific power on flower

Yisheng ZHANG, Delan ZHU

《农业科学与工程前沿（英文）》 2017年第4卷第2期页码 165-171 doi: 10.15302/J-FASE-2017145

摘要： To determine the main parameters of droplet strike damage and avoid flower injury due to the unsuitable practices during sprinkler irrigation, an indoor experiment of irrigation droplet impact on cyclamen was conducted. The influences of different parameters such as droplet diameter, application intensity, specific power on flower strike damage was analyzed using Image Pro-Plus software to compute strike damage area and define damage level by sense-analysis. The results showed that a damage area of <1% represents a safe irrigation level, 1%–3% slight damage level, 3%–6% moderate damage level, and>6% heavy damage level. Equations of application intensity, specific power with sprinkler irrigation time and flower injury ratio were regressed against parameters which cause impact damages. The results indicated that specific power has a significant correlation with injury, and flower damage area increased as the increasing of the value of specific power for the same irrigation time. Application intensity was also correlated with injury when the droplet diameter was larger than 1 mm. When the duration of sprinkler irrigation was 1, 5 and 10 min, the threshold of impinging damage of application intensity was 25.30, 5.01 and 1.64 mm·h and the specific power was 0.467×10 , 9.340×10 and 3.110×10 W·m . These results provide a reference for determining the suitable values of sprinkler properties in operation design.

关键词： application intensity damage floriculture flowers specific power sprinkler irrigation

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The origins of schedule management: the concepts used in planning, allocating, visualizing and managing

Lynda M. BOURNE, Patrick WEAVER

《工程管理前沿（英文）》 2018年第5卷第2期页码 150-166 doi: 10.15302/J-FEM-2018012

摘要： Getting the in the at the has always been a major organizational challenge. In ancient times this process seems to have been accomplished based on the scheme of arrangements being contained in the leader’s mind and instructions communicated verbally. Modern approaches to solving the twin challenges of first thinking through the ‘plan’ and then communicating the plan to the people who need to do ‘ ’ use sophisticated graphics, charts, diagrams, and computations. This paper traces the development of the concepts most project managers take for granted including bar charts and critical path schedules from their origins (which are far earlier than most people think) through to the modern day. The first section of the paper looks at the development of concepts that allow the visualization of time and other data. The second looks at the shift from static representations to dynamic modeling through the emergence of computers, dynamic calculations and integrated data from the 1950s to the present time.

关键词： time management scheduling CPM PERT Gantt Critical Path bar chart

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基于仿真的长距离引水隧洞施工全过程进度实时控制与可视化分析研究

胡连兴,佟大威,焦凯

《中国工程科学》 2011年第13卷第12期页码 97-102

摘要：

长距离引水隧洞常具有埋深大、洞线长、洞径大和工程地质条件极其复杂等特点，各工序工程量大，相互间影响巨大，因此，在实际施工过程中内外环境和约束条件可能发生变化，使原定的施工进度计划与实际施工进程不可避免地产生偏差。如果这种偏差不及时纠正，将会越来越大，以致原计划进度起不到指导实际施工的作用。文章利用计算机仿真技术、控制论思想和虚拟现实技术，提出了基于仿真的长距离引水隧洞施工全过程进度实时控制与可视化分析方法，对施工进度的实时控制提供了可行性研究和科学依据。

关键词：长距离引水隧洞施工进度实时控制可视化仿真

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Alternate partial root-zone irrigation with high irrigation frequency improves root growth and reduces

Shaoqing DU, Ling TONG, Shaozhong KANG, Fusheng LI, Taisheng DU, Sien LI, Risheng DING

《农业科学与工程前沿（英文）》 2018年第5卷第2期页码 188-196 doi: 10.15302/J-FASE-2017176

摘要： Alternate partial root-zone irrigation (APRI) can improve water use efficiency in arid areas. However, the effectiveness and outcomes of different frequencies of APRI on water uptake capacity and physiological water use have not been reported. A two-year field experiment was conducted with two irrigation amounts (400 and 500 mm) and three irrigation methods (conventional irrigation, APRI with high and low frequencies). Root length density, stomatal conductance, photosynthetic rate, transpiration rate, leaf water use efficiency, midday stem and leaf water potentials were measured. The results show that in comparison with conventional irrigation, APRI with high frequency significantly increased root length density and decreased water potentials and stomatal conductance. No differences in the above indicators between the two APRI frequencies were detected. A significantly positive relationship between stomatal conductance and root length density was found under APRI. Overall, alternate partial root-zone irrigation with high frequency has a great potential to promote root growth, expand water uptake capacity and reduce unproductive water loss in the arid apple production area.

关键词： alternate partial root-zone irrigation apple tree leaf water use efficiency root length density stomatal conductance water potential

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Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China

Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU

《农业科学与工程前沿（英文）》 2016年第3卷第1期页码 55-64 doi: 10.15302/J-FASE-2016091

摘要： Scientific irrigation and nitrogen management is important for agricultural production in arid areas. To quantify the effect of water and nitrogen management on yield components, biomass partitioning and harvest index ( ) of maize for seed production with plastic film-mulching, field experiments including different irrigation and N treatments were conducted in arid north-west China in 2013 and 2014. The results indicated that kernel number per plant ( ) was significantly affected by irrigation and N treatments. However, 100-kernel weight was relatively stable. Reducing irrigation quantity significantly increased stem partitioning index ( ) and leaf partitioning index ( ), and decreased ear partitioning index ( ) at harvest, but lowering N rate (from 500 to 100 kg N·hm ) did not significantly reduce , , and at harvest. was significantly reduced by reducing irrigation quantity, but not by reducing N rate. Linear relationships were found between , , , at harvest and and evapotranspiration ( ).

关键词： yield components biomass partitioning harvest index irrigation nitrogen maize for seed production

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PLANT DENSITY, IRRIGATION AND NITROGEN MANAGEMENT: THREE MAJOR PRACTICES IN CLOSING YIELD GAPS FOR AGRICULTURAL

《农业科学与工程前沿（英文）》 2021年第8卷第4期 doi: 10.15302/J-FASE -2020355

摘要：

Agriculture faces the dual challenges of food security and environmental sustainability. Here, we investigate current maize production at the field scale, analyze the yield gaps and impacting factors, and recommend measures for sustainably closing yield gaps. An experiment was conducted on a 3.9-ha maize seed production field in arid north-western China, managed with border and drip irrigation, respectively, in 2015 and 2016. The relative yield reached 70% in both years. However, drip irrigation saved 227 mm irrigation water during a drier growing season compared with traditional border irrigation, accounting for 44% of the maize evapotranspiration (ET). Yield variability under drip irrigation was 12.1%, lower than the 18.8% under border irrigation. Boundary line analysis indicates that a relative yield increase of 8% to 10% might be obtained by optimizing the yield-limiting factors. Plant density and soil available water content and available nitrogen were the three major factors involved. In conclusion, closing yield gaps with agricultural sustainability may be realized by optimizing agronomic, irrigation and fertilizer management, using water-saving irrigation methods and using site-specific management.

关键词： boundary line analysis irrigation method precision agriculture spatial variability yield gaps yield-limiting factors

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Schedule Compression Impact on Construction Project Safety

Curt Webb,Lu Gao,Ling-guang Song

《工程管理前沿（英文）》 2015年第2卷第4期页码 344-350 doi: 10.15302/J-FEM-2015059

摘要： Many construction projects are met with stringent timelines or the threat of exorbitant liquidated damages. In addition, construction schedulers are frequently forced to incorporate aggressive schedule compression techniques. As already discussed by previous researchers, these schedule compression techniques have direct impacts on project productivity and quality defects. Researchers have also pointed out that schedule compression will affect safety incidents such as Occupational Safety & Health Administration recordable injuries and near misses over long project durations. However, most of the existing studies treated safety as a subcategory of project productivity and project quality, and minimal research has been done to directly quantify the effect of schedule compression on safety at the project level. Therefore, in this research, we conducted a survey and statistical analysis to investigate the relationship between schedule compression and safety in construction projects. We interviewed various members of the Houston construction community from both industrial and non-industrial roles. Statistical analysis was used to identify factors that have significant impacts on the occurrence of safety incidents at an industry specific level.

关键词： construction safety schedule compression overtime work shift Hurdle model

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标题作者时间类型操作

Long-term simulation of growth stage-based irrigation scheduling in maize under various water constraints

Quanxiao FANG, Liwang MA, Lajpat Rai AHUJA, Thomas James TROUT, Robert Wayne MALONE, Huihui ZHANG, Dongwei GUI, Qiang YU

期刊论文

实时灌溉预报

茆智,李远华,李会昌

期刊论文

用齐夫定律解读教材词表——评Xiao et al. (2017)《基于语料库的小学英语认识率及教材选词策略研究》

Qiong HU, Ming YUE

期刊论文

et’s disease in a Chinese population

null

期刊论文

Oxidative stress in granulosa cells contributes to poor oocyte quality and IVF-ET outcomes in women with

Qiaohong Lai, Wenpei Xiang, Qing Li, Hanwang Zhang, Yufeng Li, Guijin Zhu, Chengliang Xiong, Lei Jin

期刊论文

基于4D CAD的大型桥梁施工进度系统仿真研究

张正峰,付金强,吴康新,张发瑜

期刊论文

水稻节水灌溉及其对环境的影响

茆智

期刊论文

基于工期可控性的网络进度计划仿真评价方法研究

潘菲菲,王仁超,曹永雷

期刊论文

Influence of sprinkler irrigation droplet diameter, application intensity and specific power on flower

Yisheng ZHANG, Delan ZHU

期刊论文

The origins of schedule management: the concepts used in planning, allocating, visualizing and managing

Lynda M. BOURNE, Patrick WEAVER

期刊论文

基于仿真的长距离引水隧洞施工全过程进度实时控制与可视化分析研究

胡连兴,佟大威,焦凯

期刊论文

Alternate partial root-zone irrigation with high irrigation frequency improves root growth and reduces

Shaoqing DU, Ling TONG, Shaozhong KANG, Fusheng LI, Taisheng DU, Sien LI, Risheng DING

期刊论文

Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China

Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU

期刊论文

PLANT DENSITY, IRRIGATION AND NITROGEN MANAGEMENT: THREE MAJOR PRACTICES IN CLOSING YIELD GAPS FOR AGRICULTURAL

期刊论文

Schedule Compression Impact on Construction Project Safety

Curt Webb,Lu Gao,Ling-guang Song

期刊论文

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