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Joint association of physical activity/screen time and diet on CVD risk factors in 10-year-old children

null

《医学前沿(英文)》 2012年 第6卷 第4期   页码 428-435 doi: 10.1007/s11684-012-0232-4

摘要:

The increasing prevalence of childhood overweight and obesity has been associated with an increased risk for cardiovascular disease (CVD). While several studies examined the effect of single behaviors such as physical activity (PA), sedentary behavior or diet on CVD risk, there is a lack of research on combined associations, specifically in children. Therefore, the purpose of this study was to examine the joint association of PA or screen time (ST) and diet on CVD risk factors in children. PA, ST and diet were assessed via questionnaire in 210 fifth grade students (age: 10.6±0.4 years). The healthy eating index (HEI) was subsequently calculated as indicator for diet quality. Height, weight, % body fat, and resting blood pressure were measured according to standard procedures and blood samples obtained via fingerprick were assayed for blood lipids. Total cholesterol HDL ratio (TC:HDL), mean arterial pressure (MAP), and % body fat were used as indicators of CVD risk. 55% of children did not meet current PA recommendations on at least 5 days/week and 70% exceeded current recommendations for ST. Further, only 2.5% possessed a “good” diet (HEI>80). There was no significant association of PA or ST and diet on CVD risk score. Neither TC:HDL, MAP, and % body fat nor the total CVD risk score was significantly correlated with diet, PA, or ST. Children in the high PA group, however, had significantly better diet scores. Despite the fact that self-reported PA, ST, or dietary intake were not directly related to CVD risk in this sample, higher activity levels were associated with a healthier diet and lower ST indicating an overall healthier lifestyle of this subgroup.

关键词: exercise     sedentary behavior     metabolic syndrome     health behavior     adolescents     TV time     healthy eating index    

Analyzing the distinguishing factors that affect childhood obesity in South Korea

So Jung Yang, Hun-Sung Kim, Kun-Ho Yoon

《医学前沿(英文)》 2018年 第12卷 第6期   页码 707-716 doi: 10.1007/s11684-018-0660-x

摘要:

Understanding obesity in children is crucial because it can lead to adulthood obesity and result in fatal chronic diseases. Distinctive factors associated with obesity in adults have been described, but distinctive factors related to children remain unclear. We analyzed the correlation between the percentage of body mass index and lifestyle habits by conducting surveys on physical, nutritional, and psychological factors, and we used annual physical examination data to compare different traits among elementary school students (n = 197) and middle school students (n = 461). Our study revealed that the computing hours in elementary school students with overweight and obesity were significantly correlated with the percentage of body mass index (r = 0.29 on school days and r = 0.35 on days off, all P<0.05). No statistically significant difference was found (all P>0.05) in the computing hours of middle school students with overweight and obesity. Childhood obesity can cause depression and reduce children’s quality of life because of their distorted body perception. In conclusion, physical factors directly affecting childhood obesity and psychological and environmental factors surrounding a child should be considered.

关键词: screen time     quality of life     eating habits     childhood obesity     percentage of body mass index    

A potentiometric cobalt-based phosphate sensor based on screen-printing technology

Lei ZHU,Xiaohong ZHOU,Hanchang SHI

《环境科学与工程前沿(英文)》 2014年 第8卷 第6期   页码 945-951 doi: 10.1007/s11783-013-0615-z

摘要: A potentiometric cobalt-based screen-printing sensor was fabricated by electroplating cobalt on the surface of a screen-printing electrode as the sensitive layer for the determination of dihydrogenphosphate ( ) in wastewater samples. The electrochemical performance of this sensor was fully examined to determine its detection calibration, detection limit, response time, selectivity, and interference with pH, various ions, and dissolved oxygen (DO). The cobalt-based phosphate sensor showed a phosphate-selective potential response in the range of 10 mol·L to 10 mol·L , yielding a detection limit of 3.16 × 10 mol?L and a slope of -37.51 mV?decade in an acidic solution (pH 4.0) of . DO and pH were found to interfere with sensor responses to phosphate. Ultimately, the performance of the sensor was validated for detecting wastewater samples from the Xiaojiahe Wastewater Treatment Plant against the standard spectrophotometric methods for analysis. The discrepancy between the two methods was generally ±5% (relative standard deviation). Aside from its high selectivity, sensitivity, and stability, which are comparable with conventional bulk Co-wire sensors, the proposed phosphate sensor presents many other advantages, such as low price, compactness, ease of use, and the possibility of integration with other analytical devices, such as flow injectors.

关键词: phosphate     cobalt     screen-printing technology     electroplate     wastewater    

An investigation on patient dose in screen-film diagnostic radiology in Lhasa City, Xizang Autonomous

null

《医学前沿(英文)》 2013年 第7卷 第4期   页码 506-509 doi: 10.1007/s11684-013-0294-y

摘要:

This study aimed to investigate patient dose in diagnostic screen-film radiographic examinations in the city of Lhasa, China. Seven out of the twenty-six hospitals registered with the Lhasa Health Bureau were included in the investigation. The entrance surface air Kerma (ESAK) of seven conventional screen-film radiology X-ray equipment in these hospitals was measured with a QA dosimeter in September 2012. The X-ray examinations were divided into three categories: PA (posterior-anterior) chest, upper/lower limb, and AP (anterior-posterior) lumbar spine. For each category, ESAKs were calculated and analyzed. The mean ESAK was 0.6 mGy for PA chest, 0.3 mGy for upper/lower limb, and 1.8 mGy for AP lumbar spine. In addition, the mean ESAK value recorded for PA chest X-ray examinations exceeded the corresponding value recommended by the International Atomic Energy Agency (0.4 mGy).

关键词: radiation dosage     radiology     radiation protection     radiography/statistics & numerical data    

Defect passivation on cast-mono crystalline screen-printed cells

Alison WENHAM,Lihui SONG,Malcolm ABBOTT,Iskra ZAFIROVSKA,Sisi WANG,Brett HALLAM,Catherine CHAN,Allen BARNETT,Stuart WENHAM

《能源前沿(英文)》 2017年 第11卷 第1期   页码 60-66 doi: 10.1007/s11708-016-0443-5

摘要: Cast-mono crystalline silicon wafers contain crystallographic defects, which can severely impact the electrical performance of solar cells. This paper demonstrates that applying hydrogenation processes at moderate temperatures to finished screen print cells can passivate dislocation clusters within the cast-mono crystalline silicon wafers far better than the hydrogenation received during standard commercial firing conditions. Efficiency enhancements of up to 2% absolute are demonstrated on wafers with high dislocation densities. The impact of illumination to manipulate the charge state of hydrogen during annealing is investigated and found to not be significant on the wafers used in this study. This finding is contrary to a previous study on similar wafers that concluded increased H or H from laser illumination was responsible for the further passivation of positively charged dangling bonds within the dislocation clusters.

关键词: silicon solar cell     dislocation     cast-mono     laser     hydrogen passivation    

用于手机屏缺陷检测的基于图的两阶段分类网络 Research Article

周超凡1,2,刘妹琴3,2,1,张森林1,2,魏平3,陈霸东3

《信息与电子工程前沿(英文)》 2023年 第24卷 第2期   页码 203-216 doi: 10.1631/FITEE.2200524

摘要: 缺陷检测是手机屏质量控制的重要环节。手机屏缺陷的特性带来了一些具有挑战性的问题,包括:(1)类间相似性和类内差异性;(2)低对比度、微小尺寸或不完整缺陷的识别带来的困难;(3)针对多标签图像的类别相关性建模。为了解决这些问题,本文提出一种图推理模块,它可以堆放在常规的分类模块上。该推理模块利用类别间的依赖性、图像间的关系以及类别图像之间的相互作用来扩展特征维度,并且达到改进低质量图像特征的目的。为了进一步提高分类性能,分类模块的分类器被设计为一个余弦相似度函数。在对比学习的帮助下,分类模块可以更好地初始化推理模块的类别图。在手机屏缺陷数据集上的实验表明,所提出的两阶段网络取得了最佳性能:准确率为97.7%,F-measure为97.3%。这证明了本文所提出的方法在工业应用中是有效的。

关键词: 基于图的方法;多标签分类;手机屏缺陷;神经网络    

Plated contacts for solar cells with superior adhesion strength to screen printed solar cells

R. CHEN,S. WANG,A. WENHAM,Z. SHI,T. YOUNG,J. JI,M. EDWARDS,A. SUGIANTO,L. MAI,S. WENHAM,C. CHONG

《能源前沿(英文)》 2017年 第11卷 第1期   页码 72-77 doi: 10.1007/s11708-016-0428-4

摘要: The improvement of adhesion strength and durability of plated contacts is required for cell manufacturers to gain confidence for large-scale manufacturing. To overcome weak adhesion at the metal/Si interface, new approaches were developed. These involve the formation of laser-ablated anchor points, or grooves in the extreme case of overlapping anchor points, in the heavily doped silicon surface. When plated, these features greatly strengthen the mechanical adhesion strength of the metal. A stylus-based adhesion tester was developed specifically for evaluating the effectiveness of plated contacts to smooth silicon surfaces. The use of such a tester was also extended in this work to textured and roughened surfaces to allow evaluation of different metal contacting approaches. The adhesion strengths for various metal contacting schemes were evaluated, including screen-printed silver contacts, nickel/copper (Ni/Cu) light-induced plated (LIP) contacts for laser-doped selective emitter (LDSE) cells, buried-contact solar cells (BCSCs), and Ni/Cu LIP contacts formed with laser-ablated anchoring points in selective emitter (LAASE) cells. The latter has superior adhesion strength. The standard “peel test” of the industry was compared to the stylus-based adhesion testing, with the latter shown value for testing metal contacts on smooth surfaces but with caution needed for use with textured or roughened surfaces.

关键词: light-induced plating     metal adhesion strength     copper plating     metal contacts     solar cell durability     silicon solar cells    

亚热带地区地铁环控系统的工程实践和理论探讨

陈韶章,邓先平,贺利工

《中国工程科学》 2006年 第8卷 第10期   页码 75-79

摘要:

亚热带地区修建地铁,必须解决环境控制空调能耗大的难题。根据广州地区的气候特点和地铁建设工程实践,广州地铁研究建立了适合亚热带地区的地铁环境控制系统——应用站台屏蔽门的节能型环控系统,为低纬度地区的地铁建设提供了可持续发展的思路。

关键词: 亚热带     地铁     环控系统     屏蔽门    

General expression for linear and nonlinear time series models

Ren HUANG, Feiyun XU, Ruwen CHEN

《机械工程前沿(英文)》 2009年 第4卷 第1期   页码 15-24 doi: 10.1007/s11465-009-0015-z

摘要: The typical time series models such as ARMA, AR, and MA are founded on the normality and stationarity of a system and expressed by a linear difference equation; therefore, they are strictly limited to the linear system. However, some nonlinear factors are within the practical system; thus, it is difficult to fit the model for real systems with the above models. This paper proposes a general expression for linear and nonlinear auto-regressive time series models (GNAR). With the gradient optimization method and modified AIC information criteria integrated with the prediction error, the parameter estimation and order determination are achieved. The model simulation and experiments show that the GNAR model can accurately approximate to the dynamic characteristics of the most nonlinear models applied in academics and engineering. The modeling and prediction accuracy of the GNAR model is superior to the classical time series models. The proposed GNAR model is flexible and effective.

关键词: linear and nonlinear     autoregressive model     system identification     time series analysis    

Rapid method for on-site determination of phenolic contaminants in water using a disposable biosensor

Yuanting LI, Dawei LI, Wei SONG, Meng LI, Jie ZOU, Yitao LONG

《环境科学与工程前沿(英文)》 2012年 第6卷 第6期   页码 831-838 doi: 10.1007/s11783-012-0393-z

摘要: A disposable biosensor was fabricated using single-walled carbon nanotubes, gold nanoparticles and tyrosinase (SWCNTs-AuNPs-Tyr) modified screen-printed electrodes. The prepared biosensor was applied to the rapid determination of phenolic contaminants within 15 minutes. The SWCNTs-AuNPs-Tyr bionanocomposite sensing layer was characterized with scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry methods. The characterization results revealed that SWCNTs could lead to a high loading of tyrosinase (Tyr) with the large surface area and the porous morphology, while AuNPs could retain the bioactivity of Tyr and enhance the sensitivity. The detection conditions, including working potential, pH of supporting electrolyte and the amount of Tyr were optimumed. As an example, the biosensor for catechol determination displayed a linear range of 8.0 × 10 to 2.0 × 10 mol·L with a detection limit of 4.5 × 10 mol·L (S/ = 3). This method has a rapid response time within 10 s, and shows excellent repeatability and stability. Moreover, the resulting biosensor could be disposable, low-cost, reliable and easy to carry. This kind of new Tyr biosensor provides great potential for rapid, on-site and cost-effective analysis of phenolic contaminants in environmental water samples.

关键词: on-site determination     tyrosinase biosensor     phenolic contaminants     single-walled carbon nanotubes     gold nanoparticles     screen-printed electrodes    

Run-time system based on LinSERCANS and Soft-PLC

Cunfeng KANG, Chong WANG, Chunmin MA, Xudong HUANG, Renyuan FEI

《机械工程前沿(英文)》 2009年 第4卷 第2期   页码 120-124 doi: 10.1007/s11465-009-0019-8

摘要: Soft-PLC with open architecture is the direction of development in industrial automation. This paper discusses the method of communication between the interface functions of LinSERCANS under RTLinux and the external library of Soft-PLC under Windows. Based on the API HOOK theory, the communication between the interface functions of LinSERCANS and the external libraries of Soft-PLC is set up and it solves the calling functions of dynamic link libraries in different operation systems. It is able to combine LinSERCANS with the Soft-PLC, and a run-time system is developed based on the interface technology of the serial real-time communication system (SERCOS) and technology of soft-PLC. This run-time system has been used in all electronic injection molding machines and works very well.

关键词: Soft-PLC     run-time system     LinSERCANS     dynamic link libraries    

Two-stage scheduling on batch and single machines with limited waiting time constraint

Zhongshun SHI, Zewen HUANG, Leyuan SHI

《工程管理前沿(英文)》 2017年 第4卷 第3期   页码 368-374 doi: 10.15302/J-FEM-2017034

摘要: This study addresses the problem of two-stage scheduling on batch and single machines with limited waiting time constraint; thus, the makespan is minimized. A mixed-integer linear programming model is proposed for this problem. Three tight lower bounds and a heuristic algorithm are developed. The worst-case performance of the proposed algorithm is discussed. A hybrid differential evolution algorithm is also developed to improve the solution quantity. Numerical results show that the hybrid algorithm is capable of obtaining high-quality solutions and exhibits a competitive performance

关键词: batch machine     flow shop     makespan     limited waiting time    

Analyzing construction safety through time series methods

Houchen CAO, Yang Miang GOH

《工程管理前沿(英文)》 2019年 第6卷 第2期   页码 262-274 doi: 10.1007/s42524-019-0015-6

摘要: The construction industry produces a large amount of data on a daily basis. However, existing data sets have not been fully exploited in analyzing the safety factors of construction projects. Thus, this work describes how temporal analysis techniques can be applied to improve the safety management of construction data. Various time series (TS) methods were adopted for identifying the leading indicators or predictors of construction accidents. The data set used herein was obtained from a large construction company that is based in Singapore and contains safety inspection scores, accident cases, and project-related data collected from 2008 to 2015. Five projects with complete and sufficient data for temporal analysis were selected from the data set. The filtered data set contained 23 potential leading indicators (predictors or input variables) of accidents (output or dependent variable). TS analyses were used to identify suitable accident predictors for each of the five projects. Subsequently, the selected input variables were used to develop three different TS models for predicting accident occurrences, and the vector error correction model was found to be the best model. It had the lowest root mean squared error value for three of the five projects analyzed. This study provides insights into how construction companies can utilize TS data analysis to identify projects with high risk of accidents.

关键词: time series     temporal     construction safety     leading indicators     accident prevention     forecasting    

Convergence to real-time decision making

James M. TIEN

《工程管理前沿(英文)》 2020年 第7卷 第2期   页码 204-222 doi: 10.1007/s42524-019-0040-5

摘要: Real-time decision making reflects the convergence of several digital technologies, including those concerned with the promulgation of artificial intelligence and other advanced technologies that underpin real-time actions. More specifically, real-time decision making can be depicted in terms of three converging dimensions: Internet of Things, decision making, and real-time. The Internet of Things include tangible goods, intangible services, ServGoods, and connected ServGoods. Decision making includes model-based analytics (since before 1990), information-based Big Data (since 1990), and training-based artificial intelligence (since 2000), and it is bolstered by the evolving real-time technologies of sensing (i.e., capturing streaming data), processing (i.e., applying real-time analytics), reacting (i.e., making decisions in real-time), and learning (i.e., employing deep neural networks). Real-time includes mobile networks, autonomous vehicles, and artificial general intelligence. Central to decision making, especially real-time decision making, is the ServGood concept, which the author introduced in an earlier paper (2012). It is a physical product or good encased by a services layer that renders the good more adaptable and smarter for a specific purpose or use. Addition of another communication sensors layer could further enhance its smartness and adaptiveness. Such connected ServGoods constitute a solid foundation for the advanced products of tomorrow which can further display their growing intelligence through real-time decisions.

关键词: real-time decision making     services     goods     ServGoods     Big Data     Internet of Things     artificial intelligence     wireless communications    

Damage identification in connections of moment frames using time domain responses and an optimization

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 851-866 doi: 10.1007/s11709-021-0739-3

摘要: Damage is defined as changes to the material and/or geometric properties of a structural system, comprising changes to the boundary conditions and system connectivity, adversely affecting the system’s performance. Inspecting the elements of structures, particularly critical components, is vital to evaluate the structural lifespan and safety. In this study, an optimization-based method for joint damage identification of moment frames using the time-domain responses is introduced. The beam-to-column connection in a metallic moment frame structure is modeled by a zero-length rotational spring at both ends of the beam element. For each connection, an end-fixity factor is specified, which changes between 0 and 1. Then, the problem of joint damage identification is converted to a standard optimization problem. An objective function is defined using the nodal point accelerations extracted from the damaged structure and an analytical model of the structure in which the nodal accelerations are obtained using the Newmark procedure. The optimization problem is solved by an improved differential evolution algorithm (IDEA) for identifying the location and severity of the damage. To assess the capability of the proposed method, two numerical examples via different damage scenarios are considered. Then, a comparison between the proposed method and the existing damage identification method is provided. The outcomes reveal the high efficiency of the proposed method for finding the severity and location of joint damage considering noise effects.

关键词: damage identification     beam-to-column connection     time-domain response     optimization    

标题 作者 时间 类型 操作

Joint association of physical activity/screen time and diet on CVD risk factors in 10-year-old children

null

期刊论文

Analyzing the distinguishing factors that affect childhood obesity in South Korea

So Jung Yang, Hun-Sung Kim, Kun-Ho Yoon

期刊论文

A potentiometric cobalt-based phosphate sensor based on screen-printing technology

Lei ZHU,Xiaohong ZHOU,Hanchang SHI

期刊论文

An investigation on patient dose in screen-film diagnostic radiology in Lhasa City, Xizang Autonomous

null

期刊论文

Defect passivation on cast-mono crystalline screen-printed cells

Alison WENHAM,Lihui SONG,Malcolm ABBOTT,Iskra ZAFIROVSKA,Sisi WANG,Brett HALLAM,Catherine CHAN,Allen BARNETT,Stuart WENHAM

期刊论文

用于手机屏缺陷检测的基于图的两阶段分类网络

周超凡1,2,刘妹琴3,2,1,张森林1,2,魏平3,陈霸东3

期刊论文

Plated contacts for solar cells with superior adhesion strength to screen printed solar cells

R. CHEN,S. WANG,A. WENHAM,Z. SHI,T. YOUNG,J. JI,M. EDWARDS,A. SUGIANTO,L. MAI,S. WENHAM,C. CHONG

期刊论文

亚热带地区地铁环控系统的工程实践和理论探讨

陈韶章,邓先平,贺利工

期刊论文

General expression for linear and nonlinear time series models

Ren HUANG, Feiyun XU, Ruwen CHEN

期刊论文

Rapid method for on-site determination of phenolic contaminants in water using a disposable biosensor

Yuanting LI, Dawei LI, Wei SONG, Meng LI, Jie ZOU, Yitao LONG

期刊论文

Run-time system based on LinSERCANS and Soft-PLC

Cunfeng KANG, Chong WANG, Chunmin MA, Xudong HUANG, Renyuan FEI

期刊论文

Two-stage scheduling on batch and single machines with limited waiting time constraint

Zhongshun SHI, Zewen HUANG, Leyuan SHI

期刊论文

Analyzing construction safety through time series methods

Houchen CAO, Yang Miang GOH

期刊论文

Convergence to real-time decision making

James M. TIEN

期刊论文

Damage identification in connections of moment frames using time domain responses and an optimization

期刊论文