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A novel period estimation method for X-ray pulsars based on frequency subdivision
Li-rong SHEN,Xiao-ping LI,Hai-feng SUN,Hai-yan FANG,Meng-fan XUE
《信息与电子工程前沿(英文)》 2015年 第16卷 第10期 页码 858-870 doi: 10.1631/FITEE.1500052
关键词: Pulsar navigation Period estimation Frequency subdivision Continuous Lomb periodogram
Weixiang YAO, Xianju WANG, Yubin LAN, Ji JIN
《农业科学与工程前沿(英文)》 2018年 第5卷 第4期 页码 455-461 doi: 10.15302/J-FASE-2018232
Prewetting process can reduce the contact angle between the droplet and the leaf blade, so that the droplet can more easily wet and spread, thereby increasing the quantity of deposition. To improve the effectiveness of pesticides on cotton leaves, prewetting by single-rotor electric unmanned aerial vehicles (UAV) was studied, focusing on the effects of pesticide deposition on cotton leaves during the flowering period. Cotton leaves in 0°–30°, 30°–60°, 60°–90° leaf blade angle ranges (angle between the leaf blade and the horizontal plane) were examined. In the first experiment, four different prewetting volumes (0, 1.6, 3.2 and 4.8 L) were sprayed by a single-rotor electric UAV on four cotton plots (plots A to D) each with an area of 120 m , and then each area was sprayed with a 0.8% (w/v) ponceau 2R solution by another single-rotor electric UAV. The results revealed that with no prewetting, droplet deposition quantity decreased with increasing leaf blade inclination. After prewetting, the mean droplet deposition quantity on plots B, C and D increased by 39.8%, 9.7% and 24.9%, respectively. The prewetting rate of 1.6 L per 120 m had the most significant effect on improving the deposition of droplets. It was also found that the mean droplet deposition quantity in each leaf blade angle range increased after prewetting. For the leaf blade angle range 60° to 90°, this increase was the most pronounced, with 0.043, 0.062, 0.057 and 0.048 L·cm in plots A–D, respectively. Also, droplet deposition uniformity in the leaf blade angle range 60°–90° was better after prewetting. These results should provide a valuable reference for future research and practice to improve the effectiveness of pesticides applied to cotton by aerial applications.
关键词: aerial spray cotton deposition flowering period leaf angle prewetting UAV
《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-021-1393-7
• The long-period groundwater evolution was identified by hydrochemical signatures.
关键词: Groundwater quality Hydrochemical signatures Spatial-temporal variations Water-rock interactions Anthropogenic interventions
Mechanism design of reverse auction on concession period and generalized quality for PPP projects
Xianjia WANG, Shiwei WU
《工程管理前沿(英文)》 2017年 第4卷 第2期 页码 156-170 doi: 10.15302/J-FEM-2017016
关键词: PPP project reverse auction mechanism design multidimensional information scoring function two-stage bidding
Zhenyuan LUO, Weiming YAN, Weibing XU, Qinfei ZHENG, Baoshun WANG
《结构与土木工程前沿(英文)》 2019年 第13卷 第4期 页码 751-766 doi: 10.1007/s11709-018-0509-z
关键词: energy dissipation devices multilayer compartmental particle damper self-anchored suspension bridges shaking tables test long-period structure seismic control
Russian school of the theory and geometry of gearing: Its origin and golden period (1935 --1975)
Dmitry BABICHEV,Sergey LAGUTIN,Natalya BARMINA
《机械工程前沿(英文)》 2016年 第11卷 第1期 页码 44-59 doi: 10.1007/s11465-015-0360-z
During the second half of the twentieth century, Soviet scientists were among the world leaders in the theory and geometry of gearing or the theoretical fundamentals of designing gears and gear-cutting tools. The authors of the current paper review works related to the development of the theory of gearing (TG) written in Russian from the mid-1930s to the present. Overall, the review covers more than 400 publications of nearly 200 authors (among more than 1000 studied works). This review involves some works on gear strength and accuracy to attract more experts.
This paper presents a short list of works from the seventeenth century to the nineteenth century and discusses the basic concepts of the TG. This paper also includes a review of more than 160 papers in Russian for the period of 1935–1975, which is the “golden age” of the TG. The main features and achievements during this period are also considered.
The distinctive feature of this review is the use of diagrams that visually present TG experts and the dates and themes of their published works. The diagrams also show the following aspects: 1) The most popular and important themes in a specific period, 2) the most important publications on the themes of interest to readers, and 3) the direction of the works and scope of interests of every researcher.
关键词: theory of gearing (TG) gear geometry generating surface gear synthesis gear analysis
崔慧
《中国工程科学》 2006年 第8卷 第1期 页码 51-53
从理论上分析了在大气温度变化的影响下埋地热油管道的运行参数以及周围土壤环境均随季节变化而呈现准周期变化规律,在分析大量实际运行数据的基础上,进一步验证了该规律的合理性,建议在有关管道的节能降耗、优化运行以及经济清蜡等问题的研究中,应该考虑运行参数的滞后影响。
Nanqi REN, Han KANG, Xiuheng WANG, Nan LI
《环境科学与工程前沿(英文)》 2011年 第5卷 第2期 页码 277-282 doi: 10.1007/s11783-010-0226-x
关键词: fluorescent in situ hybridization (FISH) tetrad forming organisms (TFOs) temperature variation enhanced biological phosphorus removal (EBPR)
Hamed MANSOORI, Parviz Rezvani MOGHADDAM, Rooholla MORADI
《能源前沿(英文)》 2012年 第6卷 第4期 页码 341-350 doi: 10.1007/s11708-012-0206-x
关键词: energy efficiency specific energy net return Cobb-Douglas function
王永红,刘兵,张永刚
《中国工程科学》 2013年 第15卷 第12期 页码 107-112
特长海底隧道运营是一个极其复杂的系统工程,存在较大的不确定性和安全风险。根据隧道工程运营期风险评估的一般流程,对渤海湾海底隧道工程在其运营期的风险进行了评估。评估中考虑的主要风险因素有水害、衬砌裂损、冻害、衬砌腐蚀、震害、洞内空气污染、火灾和列车脱轨事故8 种类型。综合运用信心指数法和层次分析法,参照隧道与地下工程风险接受准则和风险等级标准,对渤海湾海底隧道运营期间的风险进行估计与评价。给出了该海底隧道运营期的风险等级,并讨论了本评估工作中尚存在的一些问题和今后有待深入的工作。
苏慧,龚维明,梁书亭
《中国工程科学》 2006年 第8卷 第7期 页码 42-46
对缺乏长期流速资料的地区,给出了一种通过当地短期流速资料推算设计基准期参考流速的方法;通过分析苏通长江公路大桥水流速度观测的有关内容,采用实测的短期实际流速记录建立流速概率分布模型,按小样本推算极值的办法,得到大桥的设计基准期的基本流速并进行相关分析,确认计算结果的合理性,建立线性回归方程;为确保大桥在动力荷载作用下的安全应用及苏通大桥工程设计、施工提供可靠的技术指导。
刘学彦,袁大军,姜 曦
《中国工程科学》 2015年 第17卷 第1期 页码 88-95
运用理论分析和数值计算相结合的方法,分别从施工期和运营期角度提出了隧道抗浮稳定合理覆土厚度设定原则和理论计算方法;对于隧道施工期,考虑土体侧向摩阻力和管片环间摩阻力的影响等较为有利因素,同时考虑未凝浆液的影响等不利因素,建立了合理覆土厚度的理论计算公式;对于隧道运营期,建议只考虑隧道上覆土体自重进行抗浮,对于存在洪水冲刷的隧道设计,其上覆土体厚度还要加上设计冲刷深度;为南京某在建隧道的纵断面设计提供了一定的参考,同时也为其他过江海盾构隧道满足抗浮稳定的覆土厚度设定提供理论支持。
L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY
《能源前沿(英文)》 2012年 第6卷 第1期 页码 47-56 doi: 10.1007/s11708-011-0159-5
关键词: artificial intelligence power distribution control state estimation
An operating state estimation model for integrated energy systems based on distributed solution
Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG
《能源前沿(英文)》 2020年 第14卷 第4期 页码 801-816 doi: 10.1007/s11708-020-0687-y
关键词: integrated energy system state estimation electricity-gas coupling energy system nonlinear coupling distributed solution
Bayes estimation of residual life by fusing multisource information
Qian ZHAO, Xiang JIA, Zhi-jun CHENG, Bo GUO
《工程管理前沿(英文)》 2018年 第5卷 第4期 页码 524-532 doi: 10.15302/J-FEM-2018034
Residual life estimation is essential for reliability engineering. Traditional methods may experience difficulties in estimating the residual life of products with high reliability, long life, and small sample. The Bayes model provides a feasible solution and can be a useful tool for fusing multisource information. In this study, a Bayes model is proposed to estimate the residual life of products by fusing expert knowledge, degradation data, and lifetime data. The linear Wiener process is used to model degradation data, whereas lifetime data are described via the inverse Gaussian distribution. Therefore, the joint maximum likelihood (ML) function can be obtained by combining lifetime and degradation data. Expert knowledge is used according to the maximum entropy method to determine the prior distributions of parameters, thereby making this work different from existing studies that use non-informative prior. The discussion and analysis of different types of expert knowledge also distinguish our research from others. Expert knowledge can be classified into three categories according to practical engineering. Methods for determining prior distribution by using the aforementioned three types of data are presented. The Markov chain Monte Carlo is applied to obtain samples of the parameters and to estimate the residual life of products due to the complexity of the joint ML function and the posterior distribution of parameters. Finally, a numerical example is presented. The effectiveness and practicability of the proposed method are validated by comparing it with residual life estimation that uses non-informative prior. Then, its accuracy and correctness are proven via simulation experiments.
关键词: residual life estimation Bayes model linear Wiener process
标题 作者 时间 类型 操作
A novel period estimation method for X-ray pulsars based on frequency subdivision
Li-rong SHEN,Xiao-ping LI,Hai-feng SUN,Hai-yan FANG,Meng-fan XUE
期刊论文
Effect of UAV prewetting application during the flowering period of cotton on pesticide droplet deposition
Weixiang YAO, Xianju WANG, Yubin LAN, Ji JIN
期刊论文
Using hydrochemical signatures to characterize the long-period evolution of groundwater information in
期刊论文
Mechanism design of reverse auction on concession period and generalized quality for PPP projects
Xianjia WANG, Shiwei WU
期刊论文
Experimental research on the multilayer compartmental particle damper and its application methods on long-period
Zhenyuan LUO, Weiming YAN, Weibing XU, Qinfei ZHENG, Baoshun WANG
期刊论文
Russian school of the theory and geometry of gearing: Its origin and golden period (1935 --1975)
Dmitry BABICHEV,Sergey LAGUTIN,Natalya BARMINA
期刊论文
Short-term effect of temperature variation on the competition between PAOs and GAOs during acclimation period
Nanqi REN, Han KANG, Xiuheng WANG, Nan LI
期刊论文
analysis in conventional and organic rice production systems and organic scenarios in the transition period
Hamed MANSOORI, Parviz Rezvani MOGHADDAM, Rooholla MORADI
期刊论文
Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution
L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY
期刊论文
An operating state estimation model for integrated energy systems based on distributed solution
Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG
期刊论文