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BDS/GPS双系统定轨 1

BDS码偏差 1

NOx 1

低轨卫星精密定轨 1

星载BDS/GPS 1

浓淡燃烧 1

燃烧器 1

锅炉 1

非线性状态空间模型；测量值偏差；扩展卡尔曼滤波；扩展卡尔曼平滑；最大期望算法 1

风云-3C 1

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Common biases in client involved decision-making in the AEC industry

Sujesh F. SUJAN, Arto KIVINIEMI, Steve W. JONES, Jacqueline M. WHEATHCROFT, Eilif HJELSETH

《工程管理前沿（英文）》 2019年 第6卷 第2期   页码 221-238 doi: 10.1007/s42524-019-0026-3

摘要： Understanding of the constitution of client involved decisions is important for future improvements of the processes. Significant decisions in construction projects are reliant on heuristic processes where assumptions are developed from past experience. The paper presents a methodology to collect empirical data in an unstructured manner utilizing participant intuition and experience regarding project level collaboration, a term easily understood by practitioners. Empirical data collected from 6 focus group discussions in Norway and 18 individual interviews in Finland is associated with biases in decision making aimed at bridging the gap of understanding and literature’s insufficient coverage. An analytic framework was developed to suit the diverse emergence of concepts to allow application of psychological principles in a structured manner to empirical data. The paper contributes by identifying types of cognitive and motivational biases in client involved decisions. The biases are found to be alleviated by one another depending on the particular application of the decision. Findings suggest that normative beliefs exist developed from past experience and habitual thinking. A number of emerged biases in this domain are alleviated from normative beliefs which are discussed in this paper.

关键词： collaboration     construction industry     social science     decision-making     client     cognitive bias     motivational bias     holistic analysis     human factor    

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A combined modulated feedback and temperature compensation approach to improve bias drift of a closed-loop

Ming-jun MA,Zhong-he JIN,Hui-jie ZHU

《信息与电子工程前沿（英文）》 2015年 第16卷 第6期   页码 497-510 doi: 10.1631/FITEE.1400349

摘要： The bias drift of a micro-electro-mechanical systems (MEMS) accelerometer suffers from the 1/ noise and the temperature effect. For massive applications, the bias drift urgently needs to be improved. Conventional methods often cannot address the 1/ noise and temperature effect in one architecture. In this paper, a combined approach on closed-loop architecture modification is proposed to minimize the bias drift. The modulated feedback approach is used to isolate the 1/ noise that exists in the conventional direct feedback approach. Then a common mode signal is created and added into the closed loop on the basis of modulated feedback architecture, to compensate for the temperature drift. With the combined approach, the bias instability is improved to less than 13 μ , and the drift of the Allan variance result is reduced to 17 μ at 100 s of the integration time. The temperature coefficient is reduced from 4.68 to 0.1 m /°C. The combined approach could be useful for many other closed-loop accelerometers.

关键词： Bias drift     Closed-loop MEMS accelerometer     Modulated feedback approach     Temperature compensation    

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Dependence of error sensitivity of frequency on bias voltage in force-balanced micro accelerometer

Lili CHEN, Wu ZHOU

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 146-149 doi: 10.1007/s11465-013-0260-z

摘要：

To predict more precisely the frequency of force-balanced micro accelerometer with different bias voltages, the effects of bias voltages on error sensitivity of frequency is studied. The resonance frequency of accelerometer under closed loop control is derived according to its operation principle, and its error sensitivity is derived and analyzed under over etching structure according to the characteristics of Deep Reaction Ion Etching (DRIE). Based on the theoretical results, micro accelerometer is fabricated and tested to study the influences of AC bias voltage and DC bias voltage on sensitivity, respectively. Experimental results indicate that the relative errors between test data and theory data are less than 7%, and the fluctuating value of error sensitivity under the range of voltage adjustment is less than 0.01 μm . It is concluded that the error sensitivity with designed parameters of structure, circuit and process error can be used to predict the frequency of accelerometer with no need to consider the influence of bias voltage.

关键词： Micro-Electro-Mechanical Systems (MEMS)     micro accelerometer     force-balanced micro accelerometer     frequency     error sensitivity    

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A method for quantifying bias in modeled concentrations and source impacts for secondary particulate

Cesunica E. Ivey, Heather A. Holmes, Yongtao Hu, James A. Mulholland, Armistead G. Russell

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0866-6

摘要： A method for quantifying source impacts for secondary PM species is derived. The method provides estimates of bias in modeled concentrations. Adjusted concentrations match corresponding observations at monitored locations. Sources impacts on secondary species are estimated over the US for 20 sources. Community Multi-Scale Air Quality (CMAQ) estimates of sulfates, nitrates, ammonium, and organic carbon are highly influenced by uncertainties in modeled secondary formation processes, such as chemical mechanisms, volatilization, and condensation rates. These compounds constitute the majority of PM mass, and reducing bias in estimated concentrations has benefits for policy measures and epidemiological studies. In this work, a method for adjusting source impacts on secondary species is developed that provides estimates of source contributions and reduces bias in modeled concentrations compared to observations. The bias correction adjusts concentrations and source impacts based on the difference between modeled concentrations and observations while taking into account uncertainties at the location of interest; and it is applied both spatially and temporally. We apply the method over the US for 2006. The mean bias for initial CMAQ concentrations compared to observations is −0.28 (OC), 0.11 (NO ), 0.05 (NH ), and −0.08 (SO ). The normalized mean bias in modeled concentrations compared to observations was effectively zero for OC, NO , NH , and SO after applying the secondary bias correction. 10-fold cross-validation was conducted to determine the performance of the spatial application of the bias correction. Cross-validation performance was favorable; correlation coefficients were greater than 0.69 for all species when comparing observations and concentrations based on kriged correction factors. The methods presented here address model uncertainties by improving simulated concentrations and source impacts of secondary particulate matter through data assimilation. Secondary-adjusted concentrations and source impacts from 20 emissions sources are generated for 2006 over continental US.

关键词： Particulate matter     Source apportionment     Secondary particulate matter     Chemical transport modeling     Receptor modeling    

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风包粉系列浓淡煤粉燃烧技术的研究

秦裕琨,李争起,孙锐,陈力哲,孙绍增,朱群益,李瑞扬,高继慧,吴少华

《中国工程科学》 2002年 第4卷 第11期   页码 42-49

摘要：

总结了哈尔滨工业大学15年来对浓淡煤粉燃烧技术的研究成果，阐述了浓淡煤粉燃烧技术的原理及所具有的风包粉流动特点，并通过工业试验验证了风包粉原理。针对我国电站锅炉燃煤的特点，提出了需要解决的5个问题，指出了浓淡燃烧技术的发展方向。

关键词： 锅炉     燃烧器     浓淡燃烧     NOx    

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Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source data

Yilan Cui, Xing Xie, Yi Liu

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1068-1

摘要：

Check-in and survey data are explored to identify personal activity-specific places.

Ways for detecting and moderating sample bias of Weibo check-in data is proposed.

A graphic representation of urban activity intensity in Beijing, China is presented.

The potential application of Weibo check-in data for urban analysis is introduced.

关键词： Social media     Human mobility     Population bias     Sample reconstruction     Data integration    

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Same stimuli, different responses: a pilot study assessing air pollution visibility impacts on emotional well-being in a controlled environment

《环境科学与工程前沿（英文）》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1620-5

摘要：

● Emotional responses to visibility-reducing haze was assessed in a controlled lab.

关键词： Air pollution     Emotional wellbeing     Variability     Visual exposure     Emotional bias    

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针对目标跟踪的两种基于最大期望算法测量值偏差估计过程的性能分析 None

Zhi-hua LU, Meng-yao ZHU, Qing-wei YE, Yu ZHOU

《信息与电子工程前沿（英文）》 2018年 第19卷 第9期   页码 1151-1165 doi: 10.1631/FITEE.1800214

摘要： 在现实目标跟踪问题中，传感器采集的测量值，比如系统缺陷，可能存在一定程度偏差。为正确估计目标的运动轨迹，测量值偏差的识别与估计将成为首要任务。首先，提出两种状态空间模型，分别把测量值偏差视为随机变量和常数。其次，假设测量值样本数足够大，基于最大期望算法，利用扩展卡尔曼滤波和平滑，针对两种模型提出不同的循环迭代偏差估计过程。最后，分析这两种估计过程的全局收敛结果，揭示其内在联系。结果表明，第二种估计过程比第一种估计过程更简单准确，并且收敛速度更快。批量处理测量值样本后，可同时获得目标运动轨迹和测量值偏差的估计结果。

关键词： 非线性状态空间模型；测量值偏差；扩展卡尔曼滤波；扩展卡尔曼平滑；最大期望算法    

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Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

《工程管理前沿（英文）》 2018年 第5卷 第2期   页码 195-201 doi: 10.15302/J-FEM-2017052

摘要： In this work, we examine the impact of crude distillation unit (CDU) model errors on the results of refinery-wide optimization for production planning or feedstock selection. We compare the swing cut+ bias CDU model with a recently developed hybrid CDU model (Fu et al., 2016). The hybrid CDU model computes material and energy balances, as well as product true boiling point (TBP) curves and bulk properties (e.g., sulfur % and cetane index, and other properties). Product TBP curves are predicted with an average error of 0.5% against rigorous simulation curves. Case studies of optimal operation computed using a planning model that is based on the swing cut+ bias CDU model and using a planning model that incorporates the hybrid CDU model are presented. Our results show that significant economic benefits can be obtained using accurate CDU models in refinery production planning.

关键词： impact of model accuracy on production planning     swing cut+ bias CDU model     hybrid CDU model     refinery feedstock selection optimization     optimization of refinery operation    

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Theoretical prediction and validation of global horizontal solar irradiance for a tropical climate in India

Sivasankari SUNDARAM,Jakka SARAT CHANDRA BABU

《能源前沿（英文）》 2015年 第9卷 第3期   页码 311-321 doi: 10.1007/s11708-015-0369-3

摘要： This paper aims to propose monthly models responsible for the theoretical evaluation of the global horizontal irradiance of a tropical region in India which is Sivagangai situated in Tamilnadu. The actual measured global horizontal irradiance hails from a 5 MW solar power plant station located at Sivagangai in Tamilnadu. The data were monitored from May 2011 to April 2013. The theoretical assessment was conducted differently by employing a programming platform called Microsoft Visual Basic 2010 Express. A graphical user interface was created using Visual Basic 2010 Express, which provided the evaluation of empirical parameters for model formulation such as daily sunshine duration ( ), maximum possible sunshine hour duration ( ), extra terrestrial horizontal global irradiance ( ) and extra terrestrial direct normal irradiance ( ). The proposed regression models were validated by the significance of statistical indicators such as mean bias error, root mean square error and mean percentage error from the predicted and the actual values for the region considered. Comparison was made between the proposed monthly models and the existing normalized models for global horizontal irradiance evaluation.

关键词： global horizontal irradiance (GHI)     mean bias error     root mean square error     mean percentage error     coefficient of regression     Visual Basic 2010 Express    

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An industrial solution to light-induced degradation of crystalline silicon solar cells

Meng XIE,Changrui REN,Liming FU,Xiaodong QIU,Xuegong YU,Deren YANG

《能源前沿（英文）》 2017年 第11卷 第1期   页码 67-71 doi: 10.1007/s11708-016-0430-x

摘要： Boron-oxygen defects can cause serious light-induced degradation (LID) of commercial solar cells based on the boron-doped crystalline silicon (c-Si), which are formed under the injection of excess carriers induced either by illumination or applying forward bias. In this contribution, we have demonstrated that the passivation process of boron-oxygen defects can be induced by applying forward bias for a large quantity of solar cells, which is much more economic than light illumination. We have used this strategy to trigger the passivation process of batches of aluminum back surface field (Al-BSF) solar cells and passivated emitter and rear contact (PERC) solar cells. Both kinds of the treated solar cells show high stability in efficiency and suffer from very little LID under further illumination at room temperature. This technology is of significance for the suppression of LID of c-Si solar cells for the industrial manufacture.

关键词： Boron-oxygen defects     c-Si solar cells     light-induced degradation     passivation     forward bias    

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基于2013年、2015年和2017年星载BDS/GPS观测数据的FY-3C卫星精密轨道确定 Article

李星星, 张柯柯, 孟祥广, 张伟, 张倩, 张小红, 李昕

《工程（英文）》 2020年 第6卷 第8期   页码 904-912 doi: 10.1016/j.eng.2019.09.001

摘要：

本文基于2013—2017年FY-3C卫星星载BDS和GPS观测数据，研究了星载BDS的定轨性能及其对低轨卫星精密定轨的贡献。结果显示，改正BDS卫星码偏差可以提高低轨卫星定轨精度，提升幅度可达12.4%。2013年、2015年和2017年的FY-3C卫星单GPS定轨的重叠轨道差异平均一维均方根（1D RMS）分别为2.0 cm、1.7 cm和1.5 cm。由于BDS二代区域系统和FY-3C较少的BDS跟踪通道，FY-3C卫星单BDS定轨的精度要远差于单GPS定轨，其2013年、2015年和2017年重叠轨道1D RMS分别为150.9 cm、115.0 cm和47.4 cm。对于BDS+GPS (GC)双系统定轨，FY-3C卫星在2013年、2015年和2017年的重叠轨道精度分别为2.5 cm、2.3 cm和1.6 cm。当不采用BDS GEO卫星观测值后，GC双系统定轨精度得到了显著提高，这是因为GEO卫星本身卫星跟踪条件较差且其轨道钟差产品精度不高。得益于近年来IGS精密轨道钟差产品精度的不断提高，特别是2015年高采样率（30 s采样间隔）卫星钟差产品的发布，FY-3C卫星的单BDS和GC双系统定轨精度从2013年开始逐步提高。此外，在不考虑BDS GEO观测值的条件下，GC双系统定轨结果在2017年要略优于单GPS定轨，这一结果说明BDS和GPS双系统融合能够提高低轨卫星的定轨精度。同时，由于系统冗余，GC双系统能够显著提高低轨卫星定轨的可靠性。随着未来更多BDS卫星发射升空以及BDS卫星产品精度的不断提高，BDS卫星将会为低轨卫星精密定轨做出更大的贡献。

关键词： 风云-3C     低轨卫星精密定轨     星载BDS/GPS     BDS码偏差     BDS/GPS双系统定轨    

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标题 作者 时间 类型 操作

Common biases in client involved decision-making in the AEC industry

Sujesh F. SUJAN, Arto KIVINIEMI, Steve W. JONES, Jacqueline M. WHEATHCROFT, Eilif HJELSETH

期刊论文

A combined modulated feedback and temperature compensation approach to improve bias drift of a closed-loop

Ming-jun MA,Zhong-he JIN,Hui-jie ZHU

期刊论文

Dependence of error sensitivity of frequency on bias voltage in force-balanced micro accelerometer

Lili CHEN, Wu ZHOU

期刊论文

A method for quantifying bias in modeled concentrations and source impacts for secondary particulate

Cesunica E. Ivey, Heather A. Holmes, Yongtao Hu, James A. Mulholland, Armistead G. Russell

期刊论文

风包粉系列浓淡煤粉燃烧技术的研究

秦裕琨,李争起,孙锐,陈力哲,孙绍增,朱群益,李瑞扬,高继慧,吴少华

期刊论文

Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source data

Yilan Cui, Xing Xie, Yi Liu

期刊论文

Same stimuli, different responses: a pilot study assessing air pollution visibility impacts on emotional well-being in a controlled environment

期刊论文

针对目标跟踪的两种基于最大期望算法测量值偏差估计过程的性能分析

Zhi-hua LU, Meng-yao ZHU, Qing-wei YE, Yu ZHOU

期刊论文

Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

期刊论文

Theoretical prediction and validation of global horizontal solar irradiance for a tropical climate in India

Sivasankari SUNDARAM,Jakka SARAT CHANDRA BABU

期刊论文

An industrial solution to light-induced degradation of crystalline silicon solar cells

Meng XIE,Changrui REN,Liming FU,Xiaodong QIU,Xuegong YU,Deren YANG

期刊论文

基于2013年、2015年和2017年星载BDS/GPS观测数据的FY-3C卫星精密轨道确定

李星星, 张柯柯, 孟祥广, 张伟, 张倩, 张小红, 李昕

期刊论文