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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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Simulation of bubble column reactors using CFD coupled with a population balance model

Tiefeng WANG

《化学科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 162-172 doi: 10.1007/s11705-009-0267-5

摘要： Bubble columns are widely used in chemical and biochemical processes due to their excellent mass and heat transfer characteristics and simple construction. However, their fundamental hydrodynamic behaviors, which are essential for reactor scale-up and design, are still not fully understood. To develop design tools for engineering purposes, much research has been carried out in the area of computational fluid dynamics (CFD) modeling and simulation of gas-liquid flows. Due to the importance of the bubble behavior, the bubble size distribution must be considered in the CFD models. The population balance model (PBM) is an effective approach to predict the bubble size distribution, and great efforts have been made in recent years to couple the PBM into CFD simulations. This article gives a selective review of the modeling and simulation of bubble column reactors using CFD coupled with PBM. Bubble breakup and coalescence models due to different mechanisms are discussed. It is shown that the CFD-PBM coupled model with proper bubble breakup and coalescence models and interphase force formulations has the ability of predicting the complex hydrodynamics in different flow regimes and, thus, provides a unified description of both the homogeneous and heterogeneous regimes. Further study is needed to improve the models of bubble coalescence and breakup, turbulence modification in high gas holdup, and interphase forces of bubble swarms.

关键词： bubble column     computational fluid dynamics     bubble breakup and coalescence     population balance model     bubble size distribution    

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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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Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 43-48 doi: 10.1007/s11783-012-0397-8

摘要： The effects of hydraulic retention time (HRT) on the nitrification activities and population dynamics of a conventional activated sludge system fed with synthetic inorganic wastewater were investigated over a period of 260 days. When the HRT was gradually decreased from 30 to 5 h, the specific ammonium-oxidizing rates (SAOR) varied between 0.32 and 0.45 kg (kg mixed liquor suspended solids (MLSS)·d) , and the specific nitrate-forming rates (SNFR) increased from 0.11 to 0.50 kg (kg MLSS·d) , showing that the decrease in HRT led to a significant increase in the nitrite oxidation activity. According to fluorescence in situ hybridization (FISH) analysis results, the proportion of ammonia-oxidizing bacteria (AOBs) among the total bacteria decreased from 33% to 15% with the decrease in HRT, whereas the fraction of nitrite-oxidizing bacteria (NOBs), particularly the fast-growing sp., increased significantly (from 4% to 15% for NOBs and from 1.5% to 10.6% for sp.) with the decrease in HRT, which was in accordance with the changes in SNFR. A short HRT favored the relative growth of NOBs, particularly the fast-growing sp., in the conventional activated sludge system.

关键词： ammonia-oxidizing bacteria     hydraulic retention time     nitrification activity     nitrite-oxidizing bacteria     population dynamics    

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Socialized care services for the aged population: System construction and support measures

《工程管理前沿（英文）》 2023年 第10卷 第2期   页码 339-353 doi: 10.1007/s42524-022-0208-2

摘要： Given the aging society, an increase in social demand, information- and communication technology-driven culture, and government policy support emerges to enable the development of the socialized care services system for the aged (SCSSA). The development of the SCSSA would be a significant step toward addressing China’s aging population. However, the construction of the SCSSA challenges the theories and methods of traditional elderly care service system construction. Specifically, the implementation path for such elderly care service policies is unclear, the necessary technological support is insufficient, and the mechanism for integrating intelligent information technology remains underexplored. Thus, this paper focuses on the needs of the elderly, grounded in the context of the changing elderly care service policies in China, and proposes a research paradigm that integrates system construction and support measure embedding. We then construct the original SCSSA, which includes “material + spirit + medical treatment + healthcare” and propose a method of optimization and iteration. Finally, we build the research framework of systematic support measures from the perspectives of policy reconstruction, institutional embeddedness, and technical support. Our work provides theoretical support and practical guidance for the construction and dynamic optimization of the SCSSA, thus making a significant contribution that will help China effectively cope with its aging society.

关键词： socialized     care service for the elderly     system construction     support measure    

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Obesity and overweight prevalence and its association with undiagnosed hypertension in Shanghai population, China: a cross-sectional population-based survey

null

《医学前沿（英文）》 2012年 第6卷 第3期   页码 322-328 doi: 10.1007/s11684-012-0204-8

摘要：

The aim of this study was to determine the prevalence of overweight and obese subjects in the Shanghai population of China and its association with undiagnosed hypertension, by taking age, gender and place of residence (urban or suburban) into account. A cross-sectional population-based survey was conducted in 2007. The sample included 13 359 participants aged 15–69 years. Weight, height, and blood pressure were recorded, and information about gender, age and place of residence was obtained. Overweight and obesity prevalence were calculated by the body mass index (BMI) definition recommended by Working Group on Obesity in China (normal weight, 18.5–23.9 kg/m2; overweight, 24–27.9 kg/m2; obesity,≥28 kg/m2). Undiagnosed hypertension was defined by China criteria in accord with that of WHO-ISH (subjects with systolic pressure≥140 mmHg, and/or diastolic pressure≥90 mmHg). Multiple logistic regression analyses were used to assess the association of overweight or obesity with undiagnosed hypertension by adjusting for age, gender and place of residence. The overall overweight, obesity, and undiagnosed hypertension prevalence were 27.6% (95% CI: 26.8–28.4), 6.6% (95% CI: 6.2–7.0), and 15.5% (95% CI: 14.9–16.1), respectively. Compared to normal weight subjects, the odds ratios (OR) for subjects who were overweight and had hypertension was 2.33 (95% CI: 2.10–2.59); that for obesity and hypertension was 4.27 (95% CI: 3.66–4.99). These data suggest that overweight and obesity prevalence and their association with undiagnosed hypertension are high in our study population.

关键词： overweight     obesity     undiagnosed hypertension     prevalence     association    

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Prognostic analysis of chronic myeloid leukemia in Chinese population in an imatinib era

null

《医学前沿（英文）》 2012年 第6卷 第2期   页码 204-211 doi: 10.1007/s11684-012-0202-x

摘要：

We evaluated the outcomes of chronic myeloid leukemia (CML) patients in three clinical phases, namely, chronic (CP), accelerated (AP), and blast (BP) phases, receiving imatinib treatment. The single-institution treatment experiences of Chinese patients with CML were presented. A total of 275 CML patients (CP, 210; AP, 24; and BP, 41) who received imatinib between February 2001 and April 2008 were enrolled in this study. We evaluated the responses (hematologic, cytogenetic, and molecular), overall survival (OS), treatment event-free survival (EFS), and prognostic factors of outcome. At the cut-off point, the complete cytogenetic response (CCyR) and complete molecular response rates of patients in the CP were 84.7% and 61.9%, respectively, which were significantly higher than those of patients in the AP (50% and 29.1%, respectively, both P<0.001) and BP (24.3% and 9.7%, respectively, both P<0.001). The estimated five-year OS and five-year EFS rates were 93.2% and 86.4% for CP patients, as well as 64.5% and 50.9% for AP patients, which were significantly higher than those for BP patients (P<0.001). In CP patients, univariate analysis revealed that early treatment with imatinib, achieving CCyR within 12 months, additional cytogenetic abnormalities, and kinase domain mutations were associated with the treatment outcome. More patients are needed to carry out multivariate analysis.

关键词： imatinib     chronic myeloid leukemia     complete cytogenetic response    

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Projections of heat-related excess mortality in China due to climate change, population and aging

《环境科学与工程前沿（英文）》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1732-y

摘要：

● Four scenarios were used to project heat-related excess mortality in China.

关键词： Heat-related excess mortality     LMDI     Aging     YLL     VSLY    

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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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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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Are the SNPs of NKX2-1 associated with papillary thyroid carcinoma in the Han population of Northern

null

《医学前沿（英文）》 2014年 第8卷 第1期   页码 113-117 doi: 10.1007/s11684-014-0310-x

摘要：

Papillary thyroid carcinoma (PTC) is one of the most common tumors of the thyroid gland. The common risk factors of PTC include ionizing radiation, positive family history, and thyroid nodular disease. PTC was identified in Europeans by conducting a genome-wide association study, and a strong association signal with PTC was observed in rs944289 and NKX2-1 (located at the 14q13.3 locus), which was probably the genetic risk factor of PTC. This study aimed to examine the association of this gene with PTC in Chinese. A total of 354 patients with PTC and 360 healthy control subjects from the Han population of Northern China were recruited in the study. These individuals were genotyped to determine rs12589672, rs12894724, rs2076751, and rs944289. The association of rs944289 with PTC was obtained (C vs. T, P=0.027, OR=1.264, 95% CI=1.026-1.557; and C/C-C/T vs. T/T, P=0.034, OR=1.474, 95% CI=1.028-2.112). Conducting a subgroup analysis, we found a marginal difference in the allele frequency distribution of rs944289 (adjusted P=0.062) between the patients with PTC and multi-nodular goiter and the control subjects. We also observed an interaction (P=0.029; OR=2.578, 95% CI=1.104-6.023) between rs944289 and diabetes in patients with PTC. In conclusion, rs944289 was associated with an increased risk of PTC in the Han population of Northern China, but no clear association was observed in either of the tag single nucleotide polymorphisms of NKX2-1.

关键词： NKX2-1     papillary thyroid carcinoma     the Han population of Northern China     association    

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Genetic diversity and population structure of indigenous chicken breeds in South China

Xunhe HUANG,Jinfeng ZHANG,Danlin HE,Xiquan ZHANG,Fusheng ZHONG,Weina LI,Qingmei ZHENG,Jiebo CHEN,Bingwang DU

《农业科学与工程前沿（英文）》 2016年 第3卷 第2期   页码 97-101 doi: 10.15302/J-FASE-2016102

摘要： A total of 587 individuals from 12 indigenous chicken breeds from South China and two commercial breeds were genotyped for 26 microsatellites to investigate the genetic diversity and population structure. All microsatellites were found to be polymorphic. The number of alleles per locus ranged from 5 to 36, with an average of 12.10 ± 7.00 (SE). All breeds, except White Recessive Rock, had high allelic polymorphism (>0.5). Higher genetic diversity was revealed in the indigenous chicken breeds rather than in the commercial breeds. Potential introgression from the commercial breeds into the indigenous chickens was also detected. The population structure of these indigenous chicken breeds could be explained by their geographical distribution, which suggested the presence of independent history of breed formation. Data generated in this study will provide valuable information to the conservation for indigenous chicken breeds in future.

关键词： microsatellites     genetic diversity     population structure     indigenous chicken     South China     conservation    

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Status of hyperhomocysteinemia in China: results from the China Stroke High-risk Population Screening

《医学前沿（英文）》 2021年 第15卷 第6期   页码 903-912 doi: 10.1007/s11684-021-0871-4

摘要： A nationwide survey was conducted from October 2018 to September 2019 to assess the prevalence of hyperhomocysteinemia (Hhcy) and its influencing factors in China. A standardized questionnaire was used to collect information. Hhcy was defined as the level of serum homocysteine (HCY) ≥15.0 µmol/L. The H-type hypertension (HHYP) was defined as hypertension with an elevated serum HCY (≥15.0 µmol/L). Finally, 110 551 residents ≥40 years of age from 31 provinces in the mainland of China were included. Overall, the median serum HCY level was 10.9 µmol/L (interquartile range 7.9–15.1). A total of 28 633 participants (25.9%) were defined as Hhcy. The Hhcy prevalence ranged from 7.9% in Shanghai to 56.8% in Tianjin. The data showed that serum HCY levels were associated with age, male gender, cigarette smoking, hypertension, diabetes, ethnicity, endurance in exercise (inverse), and fruit and vegetable intake (inverse). In addition, 15 486 participants were defined as HHYP, and the rate was 14.0%. HHYP was an independent predictor of stroke with an adjusted odds ratio of 1.752 (95% CI 1.338–2.105). The geographical distribution pattern of the Hhcy epidemic reflects dynamic differences, and national strategies should be carried out to further improve the care of patients with Hhcy across China.

关键词： homocysteine     hyperhomocysteinemia     H-type hypertension     Chinese    

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Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1522-y

摘要：

• Simultaneous C & N removal in Methammox occurs at wide C:N ratio.

关键词： Methanogens     Biological Nitrogen Removal (BNR)     Simultaneous     Methammox     C:N ratio    

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标题 作者 时间 类型 操作

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

Simulation of bubble column reactors using CFD coupled with a population balance model

Tiefeng WANG

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

Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

期刊论文

Socialized care services for the aged population: System construction and support measures

期刊论文

Obesity and overweight prevalence and its association with undiagnosed hypertension in Shanghai population, China: a cross-sectional population-based survey

null

期刊论文

Prognostic analysis of chronic myeloid leukemia in Chinese population in an imatinib era

null

期刊论文

Projections of heat-related excess mortality in China due to climate change, population and aging

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

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

Are the SNPs of NKX2-1 associated with papillary thyroid carcinoma in the Han population of Northern

null

期刊论文

Genetic diversity and population structure of indigenous chicken breeds in South China

Xunhe HUANG,Jinfeng ZHANG,Danlin HE,Xiquan ZHANG,Fusheng ZHONG,Weina LI,Qingmei ZHENG,Jiebo CHEN,Bingwang DU

期刊论文

Status of hyperhomocysteinemia in China: results from the China Stroke High-risk Population Screening

期刊论文

Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:

期刊论文