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Fracture model for the prediction of the electrical percolation threshold in CNTs/Polymer composites

Yang SHEN, Pengfei HE, Xiaoying ZHUANG

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 125-136 doi: 10.1007/s11709-017-0396-8

摘要： In this paper, we propose a 3D stochastic model to predict the percolation threshold and the effective electric conductivity of CNTs/Polymer composites. We consider the tunneling effect in our model so that the unrealistic interpenetration can be avoided in the identification of the conductive paths between the CNTs inside the polymer. The results are shown to be in good agreement with reported experimental data.

关键词： electrical percolation     CNTs/Polymer composites     fracture model     electric conductivity     tunnelling effects    

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Prevalence of vitamin D deficiency in girls with idiopathic central precocious puberty

null

《医学前沿（英文）》 2018年 第12卷 第2期   页码 174-181 doi: 10.1007/s11684-017-0544-5

摘要：

The relationship between vitamin D deficiency and idiopathic central precocious puberty (ICPP) has been recently documented. In this study, 280 girls diagnosed with ICPP and 188 normal puberty control girls of similar ages were enrolled and retrospectively studied. The ICPP group had significantly lower serum 25-hydroxyvitamin D (25[OH]D) levels than the control group. Furthermore, a nonlinear relationship was found between serum 25[OH]D and ICPP, and a cut-off point for serum 25[OH]D was found at 31.8 ng/ml for ICPP with and without adjusting the different confounding factors. Girls with serum 25[OH]D≥31.8 ng/ml had a lower odds ratio (unadjusted: OR 0.36, 95% CI 0.15 to 0.83, <0.05; height and weight adjusted: OR 0.44, 95% CI 0.18 to 1.08, = 0.072; BMI adjusted: OR 0.36, 95% CI 0.16 to 0.84, <0.05). The ICPP subjects with 25[OH]D deficiency had a higher body mass index (BMI) than the subjects from the two other subgroups. Correlation analysis showed that vitamin D level is correlated with BMI and some metabolic parameters in the ICPP group. Our study suggested that vitamin D status may be associated with ICPP risk and may have a threshold effect on ICPP.

关键词： idiopathic central precocious puberty     threshold effects     vitamin D status    

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Effects of thermocline on performance of underwater glider’s power system propelled by ocean thermal

Hai YANG, Jie MA,

《能源前沿（英文）》 2009年 第3卷 第4期   页码 472-479 doi: 10.1007/s11708-009-0052-7

摘要： The thermal glider’s changeable volume produces propelling force to power the glider’s descending and ascending through the thermocline. The different depth, thickness, and intensity of the thermocline at different seasons and locations affect the working processes of the glider’s power system. Based on the enthalpy method, a mathematical model of the underwater glider’s power system was established and the time efficiency of operation was introduced, so that the effects of different thermoclines on the underwater glider’s power system were analyzed theoretically. The simulation result shows that the thermocline affects the transition time of the phase change processes of working fluids within the thermal engine tubes. There exist the threshold values of the thermocline’s depth and upper thickness for the power system’s operation. A depth or upper thickness of the thermocline less than the corresponding threshold leads the power system to work abnormally. To keep the power system working efficiently, a glider must be kept in warm surface water for a certain period before it moves through cold water, so that the time efficiency of operation is reduced. A less time efficiency of operation is unfavorable to the thermal glider to penetrate through the ocean currents.

关键词： mathematical     underwater glider     system working     certain     corresponding threshold    

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Utilization threshold of surface water and groundwater based on the system optimization of crop planting

Qiang FU,Jiahong LI,Tianxiao LI,Dong LIU,Song CUI

《农业科学与工程前沿（英文）》 2016年 第3卷 第3期   页码 231-240 doi: 10.15302/J-FASE-2016101

摘要： Based on the diversity of the agricultural system, this research calculates the planting structures of rice, maize and soybean considering the optimal economic-social-ecological aspects. Then, based on the uncertainty and randomness of the water resources system, the interval two-stage stochastic programming method, which introduces the uncertainty of the interval number, is used to calculate the groundwater exploitation and the use efficiency of surface water. The method considers the minimum cost of water as the objective of the uncertainty model for surface water and groundwater joint scheduling optimization for different planting structures. Finally, by calculating harmonious entropy, the optimal exploitation utilization interval of surface water and groundwater is determined for optimal cultivation in the Sanjiang Plain. The optimal matching of the planting structure under the economic system is suitable when the mining ratio of the surface is in 44.13%–45.45% and the exploitation utilization of groundwater is in 54.82%–66.86%, the optimal planting structure under the social system is suitable when surface water mining ratio is in 47.84%–48.04% and the groundwater exploitation threshold is in 67.07%–72.00%. This article optimizes the economic-social-ecological-water system, which is important for the development of a water- and food-conserving society and providing a more accurate management environment.

关键词： economic-social-ecological     uncertainty     harmonious entropy     surface water and groundwater     utilization threshold    

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Approaching the commercial threshold of solar water splitting toward hydrogen by III-nitrides nanowires

《能源前沿（英文）》 doi: 10.1007/s11708-023-0870-z

摘要： Approaching the commercial threshold of solar water splitting toward hydrogen by III-nitrides nanowires

关键词： threshold solar water     splitting hydrogen III    

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Blind identification of threshold auto-regressive model for machine fault diagnosis

LI Zhinong, HE Yongyong, CHU Fulei, WU Zhaotong

《机械工程前沿（英文）》 2007年 第2卷 第1期   页码 46-49 doi: 10.1007/s11465-007-0007-9

摘要： A blind identification method was developed for the threshold auto-regressive (TAR) model. The method had good identification accuracy and rapid convergence, especially for higher order systems. The proposed method was then combined with the hidden Markov model (HMM) to determine the auto-regressive (AR) coefficients for each interval used for feature extraction, with the HMM as a classifier. The fault diagnoses during the speed-up and speed-down processes for rotating machinery have been successfully completed. The result of the experiment shows that the proposed method is practical and effective.

关键词： speed-up     classifier     practical     extraction     experiment    

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Multi-dimensional optimization for approximate near-threshold computing

Jing Wang, Wei-wei Liang, Yue-hua Niu, Lan Gao, Wei-gong Zhang,jwang@cnu.edu.cn,zwg771@cnu.edu.cn

《信息与电子工程前沿（英文）》 2020年 第21卷 第10期   页码 1413-1534 doi: 10.1631/FITEE.2000089

摘要： The demise of Dennard’s scaling has created both power and utilization wall challenges for computer systems. As transistors operating in the near-threshold region are able to obtain flexible trade-offs between power and , it is regarded as an alternative solution to the scaling challenge. A reduction in supply voltage will nevertheless generate significant reliability challenges, while maintaining an error-free system that generates high costs in both and consumption. The main purpose of research on computer architecture has therefore shifted from improvement to complex multi-objective optimization. In this paper, we propose a three-dimensional optimization approach which can effectively identify the best system configuration to establish a balance among , , and reliability. We use a dynamic programming algorithm to determine the proper voltage and approximate level based on three predictors: system , consumption, and output quality. We propose an which uses a hardware/software co-design fault injection platform to evaluate the impact of the error on output quality under (NTC). Evaluation results demonstrate that our approach can lead to a 28% improvement in output quality with a 10% drop in overall efficiency; this translates to an approximately 20% average improvement in accuracy, power, and .
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改进的阈值法在毫米波目标辐射信号去噪中的应用

范庆辉,李兴国

《中国工程科学》 2008年 第10卷 第7期   页码 153-157

摘要：

根据毫米波目标辐射信号小波变换的特征，使用非负小波系数作信号的小波系数，对于确定的阈值，令小于阈值的小波系数为零，大于阈值的小波系数减去常数a ，利用信号的方差函数推导了a 的取值方 法，实验表明该方法有良好的去除毫米波目标辐射信号噪声的能力

关键词： 毫米波目标辐射信号     硬阈值法     软阈值法     均方差     贝叶斯阈值    

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Multi-color space threshold segmentation and self-learning k-NN algorithm for surge test EUT status

Jian HUANG,Gui-xiong LIU

《机械工程前沿（英文）》 2016年 第11卷 第3期   页码 311-315 doi: 10.1007/s11465-016-0376-z

摘要：

The identification of targets varies in different surge tests. A multi-color space threshold segmentation and self-learning k-nearest neighbor algorithm (k-NN) for equipment under test status identification was proposed after using feature matching to identify equipment status had to train new patterns every time before testing. First, color space (L*a*b*, hue saturation lightness (HSL), hue saturation value (HSV)) to segment was selected according to the high luminance points ratio and white luminance points ratio of the image. Second, the unknown class sample Sr was classified by the k-NN algorithm with training set Tz according to the feature vector, which was formed from number of pixels, eccentricity ratio, compactness ratio, and Euler’s numbers. Last, while the classification confidence coefficient equaled k, made Sr as one sample of pre-training set Tz′. The training set Tz increased to Tz+1 by Tz′ if Tz′ was saturated. In nine series of illuminant, indicator light, screen, and disturbances samples (a total of 21600 frames), the algorithm had a 98.65% identification accuracy, also selected five groups of samples to enlarge the training set from T0 to T5 by itself.

关键词： multi-color space     k-nearest neighbor algorithm (k-NN)     self-learning     surge test    

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基于时序优化长短期记忆和自适应阈值的高排放重型柴油车识别 Research Article

许镇义1,王仁军1,2,曹洋1,3,4,康宇1,3,4

《信息与电子工程前沿（英文）》 2023年 第24卷 第11期   页码 1633-1646 doi: 10.1631/FITEE.2300005

摘要： 在实际场景中，重型柴油车是城市氮氧化物的重要来源，其排放的氮氧化物（NOx）占车辆总排放量的80％以上，颗粒物（PM）占90％以上。检测和控制重型柴油车的排放对保护公众健康至关重要。目前，道路上的车辆必须每6个月或每年定期检测一次，在车辆检查站过滤出高排放的移动源。然而，由于年检间隔时间较长，很难及时有效地筛选出高排放车辆，而且固定的阈值不能适应车辆驾驶工况的动态变化。车载诊断设备（OBD）安装在车辆内部，可以连续跟踪和实时记录排放数据。本文提出一种时间优化长短期记忆（LSTM）和自适应动态阈值方法，使用OBD数据识别重型高排放车辆。首先，建立一个时间优化LSTM排放预测模型，以解决实际中大量OBD数据流造成的时间步注意力偏重问题。然后，利用灵活的阈值标准检测浓度预测误差序列，以区分异常排放情况，该阈值随驾驶条件变化自适应计算得到。最后，引入时间序列的相似性度量策略，以纠正一些假的异常结果。在3个真实OBD时间序列排放数据集上的实验表明，该方法得到优异的高排放源识别结果。

关键词： 高排放识别；时序优化；车载诊断设备（OBD）；动态阈值    

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Temporal variation of PM-associated health effects in Shijiazhuang, Hebei

《环境科学与工程前沿（英文）》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1376-0

摘要：

•Annual mean PM2.5 in Shijiazhuang were 87, 95, and 82 µg/m3 in 2015–2017.

关键词： PM2.5     Health effects     Integrated exposure-response model     Shijiazhuang    

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Modelling the thresholds of nitrogen/phosphorus concentration and hydraulic retention time for bloom control in reclaimed water landscape

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1564-1

摘要：

● A new model for bloom control in open land scape water was constructed.

关键词： Reclaimed water landscape     Algal bloom     Nitrogen and phosphorus     Hydraulic retention time     Threshold     Control model    

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格上基于身份的门限代理重加密方案及应用 Research Articles

吴立强1,韩益亮1,杨晓元1,2,张敏情1

《信息与电子工程前沿（英文）》 2022年 第23卷 第2期   页码 258-277 doi: 10.1631/FITEE.2000366

摘要： 门限代理重加密通过设置多个代理者，不仅能有效防止单个代理者和被授权者合谋，从而违背授权者的意愿随意转化任意文件，而且能在某些代理者瘫痪或者损毁的情况下仍然提供正常服务。本文提出一个格上非交互的基于身份门限代理重加密方案，无需公钥证书。在设计方案过程中，采用了两次Shamir的秘密共享方法，一方面有效隐藏了授权者的私钥信息，另一方面通过分割代理重加密密钥，实现了代理权限的去中心化。鲁棒性是指某个代理者如果提交了非法的密文转化密文份额，那么组合者会立刻识别出这个恶意的代理者。本文方案通过格上全同态签名实现了这一属性。因此，即使未来量子攻击变得可行，我们整个方案也能完全抵抗量子攻击。本文方案的安全性在标准模型下规约为判定性差错学习困难假设。最后，给出本文方案的两个典型应用场景，包括基于区块链的文件共享系统和基于门限密码学的鲁棒密钥托管系统。

关键词： 后量子密码；门限代理重加密；格；鲁棒性；去中心化    

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Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosion

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1506-3

摘要：

• The early corrosion process in the cast iron pipes was investigated.

关键词： Cast iron pipe corrosion     Drinking water distribution systems     Chlorine disinfection     Iron-oxidizing bacteria     Coupling effects    

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Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

《结构与土木工程前沿（英文）》 2022年 第16卷 第1期   页码 99-116 doi: 10.1007/s11709-021-0799-4

摘要： In this study, bituminous binder was modified with Cocamide Diethanolamide chemical, a non-ionic surfactant, and the physical and rheological properties of modified binders were investigated. In addition, Cocamide Diethanolamide has been used for the first time to modify bituminous binder, and this situation makes the study distinctive. Bituminous binder was modified more than once with the chemical by changing modification parameters and using certain additive ratios (1%, 3%, and 5%). The effects of different modification parameters and chemical additive on modified samples were investigated with conventional bitumen tests (softening point, penetration, ductility) and Superpave tests (rotational viscometer, rolling thin film oven test, pressure aging vessel, dynamic shear rheometer, bending beam rheometer). In addition, the structural characteristics of the reference binder and modified samples were examined by X-ray diffraction, Fourier Transform Infrared Spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The examinations showed that Cocamide Diethanolamide softens bituminous binder and lowers processing temperatures. In addition, compared to reference binder, rutting resistances of modified bituminous binders decreased with the increase of additive ratio. However, modification with Cocamide Diethanolamide increased the resistance to fatigue cracks and thermal cracks.

关键词： Cocamide Diethanolamide     bitumen modification     rheology     Superpave tests    

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标题 作者 时间 类型 操作

Fracture model for the prediction of the electrical percolation threshold in CNTs/Polymer composites

Yang SHEN, Pengfei HE, Xiaoying ZHUANG

期刊论文

Prevalence of vitamin D deficiency in girls with idiopathic central precocious puberty

null

期刊论文

Effects of thermocline on performance of underwater glider’s power system propelled by ocean thermal

Hai YANG, Jie MA,

期刊论文

Utilization threshold of surface water and groundwater based on the system optimization of crop planting

Qiang FU,Jiahong LI,Tianxiao LI,Dong LIU,Song CUI

期刊论文

Approaching the commercial threshold of solar water splitting toward hydrogen by III-nitrides nanowires

期刊论文

Blind identification of threshold auto-regressive model for machine fault diagnosis

LI Zhinong, HE Yongyong, CHU Fulei, WU Zhaotong

期刊论文

Multi-dimensional optimization for approximate near-threshold computing

Jing Wang, Wei-wei Liang, Yue-hua Niu, Lan Gao, Wei-gong Zhang,jwang@cnu.edu.cn,zwg771@cnu.edu.cn

期刊论文

改进的阈值法在毫米波目标辐射信号去噪中的应用

范庆辉,李兴国

期刊论文

Multi-color space threshold segmentation and self-learning k-NN algorithm for surge test EUT status

Jian HUANG,Gui-xiong LIU

期刊论文

基于时序优化长短期记忆和自适应阈值的高排放重型柴油车识别

许镇义1,王仁军1,2,曹洋1,3,4,康宇1,3,4

期刊论文

Temporal variation of PM-associated health effects in Shijiazhuang, Hebei

期刊论文

Modelling the thresholds of nitrogen/phosphorus concentration and hydraulic retention time for bloom control in reclaimed water landscape

期刊论文

格上基于身份的门限代理重加密方案及应用

吴立强1,韩益亮1,杨晓元1,2,张敏情1

期刊论文

Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosion

期刊论文

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

期刊论文