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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Semi-implantable device based on multiplexed microfilament electrode cluster for continuous monitoring of physiological ions
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作者 Shuang Huang Shantao Zheng +9 位作者 Mengyi He Chuanjie Yao Xinshuo Huang Zhengjie Liu Qiangqiang Ouyang Jing Liu Feifei Wu Hang Gao Xi Xie Hui-jiuan Chen 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期88-103,共16页
Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in bio... Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in biological subjects.Current semi-implantable devices are mainly based on single-parameter detection.Miniaturized semi-implantable electrodes for multiparameter sensing have more restrictions on the electrode size due to biocompatibility considerations,but reducing the electrode surface area could potentially limit electrode sensitivity.This study developed a semi-implantable device system comprising a multiplexed microfilament electrode cluster(MMEC)and a printed circuit board for real-time monitoring of intra-tissue K^(+),Ca^(2+),and Na^(+)concentrations.The electrode surface area was less important for the potentiometric sensing mechanism,suggesting the feasibility of using a tiny fiber-like electrode for potentiometric sensing.The MMEC device exhibited a broad linear response(K^(+):2–32 mmol/L;Ca^(2+):0.5–4 mmol/L;Na^(+):10–160 mmol/L),high sensitivity(about 20–45 mV/decade),temporal stability(>2weeks),and good selectivity(>80%)for the above ions.In vitro detection and in vivo subcutaneous and brain experiment results showed that the MMEC system exhibits good multi-ion monitoring performance in several complex environments.This work provides a platform for the continuous real-time monitoring of ion fluctuations in different situations and has implications for developing smart sensors to monitor human health. 展开更多
关键词 Multiplexed microfilament electrode cluster Physiological ion sensing Subcutaneous and brain experiment Wearable platform for multi-ion detection Continuous real-time monitoring system
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Analog-experiment analysis of ash-deposition monitoring model of boiler economizers in power plants
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作者 程伟良 夏国栋 徐寿臣 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第6期680-683,共4页
Ash deposition is a form of particulate fouling, and appears usually in boiler economizers. The ash deposition increases capital expenditure, energy input and maintenance costs. An analog experiment for monitoring ash... Ash deposition is a form of particulate fouling, and appears usually in boiler economizers. The ash deposition increases capital expenditure, energy input and maintenance costs. An analog experiment for monitoring ash deposition was performed from the analogous objective of a 410 t/h boiler economizer to verify the rationality and reliability of the ash-deposition-monitoring model presented in order to increase the security and economy in economizer running. The analog experiment platform is a tube-shell exchanger that conforms well to the conditions of a self-modeling area. The analog flue gas in the shell side is the heated air mixed with ash, and in the tube side the fluid is water heated by the flue gas. The fluid state in the water side and the flue gas side follows the second self-modeling area. A 4-factor-3-level orthogonal table was used to schedule 9 operation conditions of orthogonal experiment, with the 4 factors being heat power, flue gas velocity, ashes grain diameter and adding ashes quantity while the three levels are different values due to different position classes in every factor. The ash deposition thermal resistances is calculated by the model with the measure parameters of temperature and pressure drop. It shows that the values of the ash deposition thermal resistances gradually increase up to a stable state. And the experimental results are reliable by F testing method at α= 0.001. Therefore, the model can be applied in online monitoring of ash deposition in a boiler economizers in power plants and provides scientific decision on ash deposition prediction and sootblowing. 展开更多
关键词 thermal power engineering monitoring model ash deposition orthogonal experiment boiler economizer tube-shell exchanger
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Changes of Organic Matter, N, P and K Content of Soils in Red Soil Areas Under Long-Term Experiment 被引量:9
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作者 JIANG Duan-sheng ZENG Xi-bai +1 位作者 GAO Ju-sheng LI Lian-fang 《Agricultural Sciences in China》 CAS CSCD 2008年第7期853-859,共7页
The content of organic matter (OM), nitrogen (N), phosphorus (P), and potassium (K) in the three selected soils, including Calcaric Purpli-Orthic Primosols (purple sand-shale parent material), Dystric Turbi-... The content of organic matter (OM), nitrogen (N), phosphorus (P), and potassium (K) in the three selected soils, including Calcaric Purpli-Orthic Primosols (purple sand-shale parent material), Dystric Turbi-Anthric Primosols (quaternary red clay parent material) and Typic Udi-Sandic Primosols (granite parent material) were studied under a long-term experiment by using crop straw and inorganic fertilizers at the Hunan Red Soil Experiment Station of Chinese Academy of Agricultural Sciences. The results showed that the contents of OM, N, P and K in the three selected soils increased after 23 years application of crop straw and inorganic fertilizers, but the contents increased much less when crop straw or inorganic fertilizers was applied alone. The nutrient contents in the three soils developed from granite changed more remarkably than those in the soil derived from quaternary red clay and purple sand-shale. It was also found that the contents of OM, N, and P increased slightly in the treatments without applying fertilizers or returning the crop straw to the root bed. Combined application of inorganic fertilizers and crop straw could remarkably increase the contents of OM, alkalihydrolyzable N and available K, the positive correlation between application of organic fertilizers and increase of OM in soil did not always happened, it provided evidence for the relation between appropriate C/N ratio and accumulation of OM in soil. The increase of nutrient content was influenced by the soil properties. By comparing the contents of nutrient in 0-20 cm depth in the three different soils, it was concluded that the most increases of OM, alkali-hydrolyzable N, and available P were observed in Typic Udi-Sandic Primosols with the average increase by 3.03, 27.38, and 21.73 mg kg^-1, respectively. The available K increased in Dystric Turbi-Anthric Primosols with the average increase by 25.82 mg kg^-1, while it decreased in Calcaric Purpli-Orthic Primosols and Typic Udi-Sandic Primosols. It was concluded that the application of inorganic fertilizer and crop straw was important to improve the soil fertility for all of three selected soils. The straw return to the field had played a significant role for enhancement of the soil quality in the study areas. The application of inorganic fertilizer combined with the straw return to the fields could remarkably improve the soil fertility. 展开更多
关键词 organic matter inorganic fertilizers NUTRIENT crop straw long-term experiment
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Investigation on long-term progressive deformation of engineering slope based on comprehensive monitoring 被引量:2
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作者 ZHANG Shi-shu GUO Song-feng +9 位作者 QI Sheng-wen TANG Feng-jiao HU Jin-shan ZHAO Xiao-ping RAN Cong-yan WANG Xin ZOU Yu HUANG Xiao-lin ZHENG Bo-wen LIANG Ning 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1576-1587,共12页
A landslide always results from a progressive process of slope deformation. In recent years, an increasing number of slope instabilities have occurred with regard to human engineering activities such as hydropower or ... A landslide always results from a progressive process of slope deformation. In recent years, an increasing number of slope instabilities have occurred with regard to human engineering activities such as hydropower or traffic construction in mountainous area, which cause even greater casualties and economic loss compared with the natural hazards. The development of such earth surface process may hold long period with mechanisms still not fully understood. Using monitoring technology is an effective and intuitive approach to assist analyzing the slope deformation process and their driving factors. This study presents an engineering slope excavated during the construction of Changheba Hydropower Station, which is located in the upper reaches of Dadu River, Sichuan Province, southwest China. The engineering slope experienced and featured a five-year continuous deformation which caused continuous high risks to the engineering activities. We conducted in-depth analysis for such a long-term deformation process based on ground and subsurface monitoring data, collected successive data with a series of monitoring equipment such as automated total station, borehole inclinometers and other auxiliary apparatus, and identified the deformation process based on the comprehensive analysis of monitoring data as well as field investigation. After analyzing the effects of engineering activities and natural factors on the continuous deformation, we found that the overburden strata provided deformable mass while the excavation-produced steep terrain initiated the slope deformation in limit equilibrium state over a long period of time;afterwards, the intense rainwater accelerated slope deformation in the rainy season. 展开更多
关键词 Engineering slope Mountainous area long-term deformation LANDSLIDES monitoring STABILITY
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Crop yields and soil organic carbon dynamics in a long-term fertilization experiment in an extremely arid region of northern Xinjiang, China 被引量:1
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作者 LYU Jinling LIU Hua +3 位作者 WANG Xihe Rodrigo OLAVE TIAN Changyan LIU Xuejun 《Journal of Arid Land》 SCIE CSCD 2017年第3期345-354,共10页
A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon (SOC) from 1990 to 2012 with seven fertilization treatments. The seven ... A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon (SOC) from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control (CK) and six different combinations of phosphorus (P), potassium (K), nitrogen (N), straw (S) and animal manure (M). The balanced fertilization treatments had significantly (P〈0.05) higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate (NPK) and 1/3 N from farmyard manure (NPKM) had a higher average yield than the other treatments. The average yields (over the 23 years) in the treatments of NPK, and urea, calcium superphosphate (NP) did not differ significantly (P〉0.05) but were higher than that in the treatment with urea and potassium sulfate (NK; P〈0.05). The results also show that the highest increases in SOC (P〈0.05) occurred in NPKM with a potential increase of 1.2 t C/(hm2.a). The increase in SOC was only 0.31, 0.30 and 0.12 t C/(hm2.a) for NPKS (9/10 N from NPK and 1/10 N from straw), NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration. 展开更多
关键词 long-term fertilization experiment extremely arid conditions soil organic carbon organic C inputs XINJIANG
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Adaptive Change Detection for Long-Term Machinery Monitoring Using Incremental Sliding-Window
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作者 Teng Wang Guo-Liang Lu +1 位作者 Jie Liu Peng Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1338-1346,共9页
Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detec... Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detection delay that limits their usages in real applications. This paper presents a new adaptive real-time change detection algorithm, an extension of the recent research by combin- ing with an incremental sliding-window strategy, to handle the multi-change detection in long-term monitoring of machine operations. In particular, in the framework, Hil- bert space embedding of distribution is used to map the original data into the Re-producing Kernel Hilbert Space (RK_HS) for change detection; then, a new adaptive threshold strategy can be developed when making change decision, in which a global factor (used to control the coarse-to-fine level of detection) is introduced to replace the fixed value of threshold. Through experiments on a range of real testing data which was collected from an experimental rotating machinery system, the excellent detection performances of the algorithm for engineering applications were demonstrated. Compared with state-of- the-art methods, the proposed algorithm can be more suitable for long-term machinery condition monitoring without any manual re-calibration, thus is promising in modern industries. 展开更多
关键词 Machine monitoring Change detection long-term monitoring Adaptive threshold
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The principles and guidelines for designing long-term agronomic experiments
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作者 Mark Conyers 《Research in Cold and Arid Regions》 2009年第1期91-97,共7页
Many of the important questions facing farming systems in the world today require long-term studies to provide meaningful information and answers. A long-term agronomic experiment (LTAE) should (1) have long-term obje... Many of the important questions facing farming systems in the world today require long-term studies to provide meaningful information and answers. A long-term agronomic experiment (LTAE) should (1) have long-term objectives; (2) study important soil processes or ecological processes; and (3) be related to the productivity and sustainability of systems. A well established LTAE can provide both insights into how the system operates and foresight into where the system goes. The prerequisites for setting up a LTAE are the secured land, continuous funding and dedicated scientists. A number of principles must be considered carefully when establishing a LTAE, (1) the site must be representative of large areas; (2) the treatments should be simple, but focusing on the big questions; (3) the plots should be large enough to allow subsequent modification of the experiment if this becomes necessary; (4) crop rotations should minimise, wherever possible, the risk of build-up of pests and diseases, and rotational phase should be considered in a rotational experiment; (5) a clearly defined experimental protocol should be developed to ensure data collected is scientifically valid and statistically analysable, but with flexibility to allow essential changes; (6) soil samples, possibly plant samples, should be achieved to provide better answer to the original questions when new, perhaps more accurate analytical techniques are developed, or answer new research questions that were not considered in the original design. The MASTER experiment in Australia was used as a case study to demonstrate how these principles are implemented in practice. 展开更多
关键词 long-term experiment SUSTAINABILITY crop rotation soil processing
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Comparison of Using an Electronic System and Conventional Monitoring Method for Monitoring the Quality of Drinking Water and Defects Discovery in Rural Area Water Distribution Network of Abarkouh, Iran 被引量:2
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作者 Reza Ali Fallahzadeh Maryam Gholami +4 位作者 Elham Madreseh Mohammad Taghi Ghaneian Mohamad Hadi Farahzadi Ali Akbar Askarnejad Shahram Sadeghi 《Health》 2015年第1期35-40,共6页
The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventi... The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventional monitoring method (According to ISIR (Institute of Standards and Industrial Research of Iran), 1053 and 4208) and use of electronic system method (Patent in industrial property general office of Iran, 77815). Free chlorine monitoring and pH test done by health workers in the conventional method and the results will be sent to the Health Network monthly. Sampling for microbiological testing is done monthly based on population (According to ISIR, 4208). On the electronic system, the procedure is also done by health workers, but the result will be sent to the receiver device by using a cell phone. According to the chlorine test results if the free chlorine residual reported zero, microbiological sampling was done by a health expert. Finally, the number of chlorine test and microbiological sampling and the results of these experiments collected in the both methods and recorded in SPSS 22 then were analyzed by using chi-square test and Fisher exact test. The result of microbiological experiments shows that the sampling rate decreased 29% in using of electronic system method in comparison to the conventional monitoring method while the number of microbial defect detection increased 19% in drinking water networks monitoring by electronic system. Using of electronic system monitoring can reduce the rate and cost of microbiological sampling and its experiments and increase accuracy of these tests, in this way it will increase the quality and safety of drinking water in distribution network in small and dispersed rural communities. 展开更多
关键词 WATER Distribution Network monitoring MICROBIOLOGICAL experiments WATER Quality RURAL Area
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Experimental study on rheological deformation and stress properties of limestone 被引量:1
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作者 唐明明 王芝银 《Journal of Central South University》 SCIE EI CAS 2008年第S1期475-478,共4页
The systematic experiment regarding the general uniaxial compression test and the creep deformations of the typical limestones from the surrounding rock of the highway tunnels were made.The relationship between the ax... The systematic experiment regarding the general uniaxial compression test and the creep deformations of the typical limestones from the surrounding rock of the highway tunnels were made.The relationship between the axial stress and the delayed deformation steady value was obtained from the creep tests under low loading stresses.By the least square method,the parameters of Nishihara creep model were calculated from the creep curves.The results indicate that the strain change always lags behind the increase of stress,and the long-term strength of the limestone is about 80.6% of the stress at the volumetric strain reversal which is obtained from the conventional uniaxial compression test. 展开更多
关键词 CREEP experiment long-term strength stress at VOLUMETRIC strain REVERSAL LIMESTONE
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Flexural failure experiment on cracked PC simply supported box girders 被引量:1
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作者 CAO Guo-hui ZHANG Wang +1 位作者 PENG Xi-rong ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2685-2692,共8页
Long-term load and flexural failure experiments are carried out on two prestressed concrete(PC) simply supported box girders. In the long-term load experiment, girder-1(G1) is in an elastic state, while girder-2(G2) i... Long-term load and flexural failure experiments are carried out on two prestressed concrete(PC) simply supported box girders. In the long-term load experiment, girder-1(G1) is in an elastic state, while girder-2(G2) is in a cracking state. To investigate the influence of cracking on the flexural behaviors of PC simply supported box beams, the experiment results are analyzed from many aspects, such as load–deflection, load–strain, and failure mode. Experiment results show the following: 1) the shrinkage and creep of concrete have considerable influences on the long-term deflection and strain of the two girders; 2) in the flexural failure experiment, the cracks and ultimate loads of the two girders are close. The rigidity degeneration of G2 is significantly faster than that of G1, and thus G2 shows nonlinear characteristics earlier; 3) to prove the validity and rationality of the current code, the cracking load and ultimate load of the two girders are calculated according to the current code. 展开更多
关键词 PC box girders long-term load experiment flexural behaviors cracks static performance
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QUICK ASSESSMENT METHODOLOGY FOR RELIABILITY OF SOLDER JOINTS IN BALL GRID ARRAY(BGA)ASSEMBLY——PART Ⅱ:RELIABILITY EXPERIMENT AND NUMERICAL SIMULATION 被引量:1
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作者 史训清 John HL Pang +2 位作者 杨前进 王志平 聂景旭 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2002年第4期356-367,共12页
In the present study,a facility,i.e.,a mechanical deflection system (MDS),was established and applied to assess the long-term reliability of the solder joints in plastic ball grid array (BGA) assembly.It was found tha... In the present study,a facility,i.e.,a mechanical deflection system (MDS),was established and applied to assess the long-term reliability of the solder joints in plastic ball grid array (BGA) assembly.It was found that the MDS not only quickly assesses the long-term reliability of solder joints within days,but can also mimic similar failure mechanisms in accelerated thermal cycling (ATC) tests. Based on the MDS and ATC reliability experiments,the acceleration factors (AF) were obtained for different reliability testing conditions.Furthermore,by using the creep constitutive relation and fatigue life model developed in part I,a numerical approach was established for the purpose of virtual life prediction of solder joints. The simulation results were found to be in good agreement with the test results from the MDS.As a result,a new reliability assessment methodology was established as an alternative to ATC for the evaluation of long-term reliability of plastic BGA assembly. 展开更多
关键词 long-term reliability plastic BGA assembly MDS reliability experiment FE numerical simulation acceleration factor
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GPS monitoring and analysis of ground movement and deformation induced by transition from open-pit to underground mining 被引量:3
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作者 Fengshan Ma Haijun Zhao +4 位作者 Yamin Zhang Jie Guo Aihua Wei Zhiquan Wu Yonglong Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2012年第1期82-87,共6页
To trace the potential hazards of open-pit slope in Longshou mine,global positioning system(GPS) is applied to monitoring ground movement and deformation induced by transition from open-pit to underground mining.Thr... To trace the potential hazards of open-pit slope in Longshou mine,global positioning system(GPS) is applied to monitoring ground movement and deformation induced by transition from open-pit to underground mining.Through long-term monitoring from 2003 to 2008,huge amounts of data were acquired.Monitoring results show that large-scale ground movement and deformation have occurred in mining area,and the movement area is ellipse-shaped.The displacement boundary of settlement trough is 2.0 km long along the exploratory line,and 1.5 km long along the strike of ore body.GPS monitoring results basically agree with the practical deformation state of open-pit slope.It is indicated that the long-term GPS monitoring is an effective way to understand the mechanism of ground movement and deformation in mine area. 更多 展开更多
关键词 open-pit ground movement long-term GPS monitoring deformation analysis
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Design and Implementation of Long-Term Single-Lead ECG Monitor
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作者 Meng Shen Shijing Xue 《Journal of Biosciences and Medicines》 2015年第4期18-23,共6页
Some heart diseases need long-term monitoring to diagnose. In this paper, we present a wearable single lead ECG monitoring device with low power consumption based on MSP430 and single-lead ECG front-end AD8232, which ... Some heart diseases need long-term monitoring to diagnose. In this paper, we present a wearable single lead ECG monitoring device with low power consumption based on MSP430 and single-lead ECG front-end AD8232, which could acquire and store patient’s ECG data for 7 days continuously. This device is available for long-term wearing with a small volume. Also, it could detect user’s motion status with an acceleration sensor and supports Bluetooth 4.0 protocol. So it could be expanded to be a dynamic heart rate monitor and/or sleep quality monitor combined with smart phone. The device has huge potential of application for health care of human daily life. 展开更多
关键词 SINGLE LEAD ECG long-term monitor Low Power CONSUMPTION
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A Study of Temperature and Aging Effects on Eigenfrequencies of Concrete Bridges for Health Monitoring
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作者 Viet Ha Nguyen Jean Mahowald +2 位作者 Sebastian Schommer Stefan Maas Arno Zuerbes 《Engineering(科研)》 2017年第5期396-411,共16页
This paper discusses the influence of environmental factors and of normal material aging on the eigenfrequencies of concrete bridges based on monitoring data registered during 4 years of a specific bridge. It is a new... This paper discusses the influence of environmental factors and of normal material aging on the eigenfrequencies of concrete bridges based on monitoring data registered during 4 years of a specific bridge. It is a new composite steel-concrete bridge built in 2006 in Luxembourg. The measurements are analyzed and compared to literature data. The final objective is the use of real monitored eigenfrequencies for structural health monitoring and damage detection based on identification of stiffness losses in practical applications. Therefore, it is very important to identify and compensate for outdoor influences namely temperature, excitation force level and normal aging effects, like creep and shrinkage of concrete and their impact on material properties. The present paper aims at describing these effects in order to separate them from damage effects. It is shown that temperature change rates and temperature gradients within the bridge have an influence on the eigenfrequencies. Hence the key idea for assessment from the full database is to select only measurements with small temperature differences and slow temperature change rates. 展开更多
关键词 DAMAGE Detection long-term monitoring EIGENFREQUENCY AGING TEMPERATURE
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Evaluation and Forecasting of Elapsed Fatigue Life of Ship Structures by Analyzing Data from Full Scale Ship Structural Monitoring
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作者 Giovanni Cusano Lt Salvatore La Marca 《Journal of Shipping and Ocean Engineering》 2015年第2期59-74,共16页
This paper describes the activities carried out by CETENA in collaboration with the Italian Navy to assess the behavior of new FREMM frigates by means of an automatic hull monitoring system and to predict the expected... This paper describes the activities carried out by CETENA in collaboration with the Italian Navy to assess the behavior of new FREMM frigates by means of an automatic hull monitoring system and to predict the expected fatigue life of ship structure by analyzing recorded data through a specifically developed post-processing tool. 展开更多
关键词 Hull monitoring system FATIGUE long-term forecasting decision support system.
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Long-Term Survival in Traumatic Brain Injury and Near-Death Experience Increases Suicide Risks: A Personal Experience and Related Literature
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作者 Robert E. Brandt Akihiro Takeuchi Hirotoshi Kamata 《Open Journal of Medical Psychology》 2022年第3期112-124,共13页
Background: Traumatic brain injury (TBI) remains a cause of lifelong disability, death, and suicide worldwide. TBI-induced near-death experience (NDE) could increase suicide risks. Objective: We investigated TBI coupl... Background: Traumatic brain injury (TBI) remains a cause of lifelong disability, death, and suicide worldwide. TBI-induced near-death experience (NDE) could increase suicide risks. Objective: We investigated TBI coupled with NDE and posttraumatic stress disorder (PTSD) as a possible indicator of suicide. Methods: A 17-year-old male who sustained an acute severe TBI in a traffic collision, was comatose 14 days, had an NDE awakening from the coma, and, years after rehabilitation, suffered PTSD, clinical depression, and survived a suicide attempt. This personal experience of a TBI-induced NDE and lingering PTSD was acquired directly from the patient by interview. We discuss his case while considering relevant literature. Results: Longitudinal data from 1961 to 2021 generated from the PubMed interface revealed 4056 TBI patients committed suicide. NDE was only reported in one of those cases and, although not a suicide, in the personal experience. Neuropsychological assessment at long-term follow-ups revealed few TBI patients exhibited normal mental/physical functions compared to the general population. Unfavorable GOS scores were risk predictors for neuropsychological/physical impairments later in life, with outcomes of depression, PTSD, poor QOL, and/or suicide. Conclusions: For TBI-NDE survivors, including those with PTSD, long-term periodic neuropsychological follow-ups and psychosocial support may help decrease suicide risks. 展开更多
关键词 Traumatic Brain Injury long-term Outcome Posttraumatic Stress Disorder Near-Death experience SUICIDE
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青少年体质健康监测政策协同的域外经验与启示 被引量:6
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作者 李凤梅 武东海 《沈阳体育学院学报》 CSSCI 北大核心 2024年第1期50-56,共7页
运用文献资料、逻辑分析等研究方法,围绕青少年体质健康监测政策协同展开研究,从美国的市场化与多元主体协同体系,日本的政府主导与家庭、学校、社区联合监测模式以及俄罗斯新版“劳卫制”下的政策协同与组织过程保障模式中得到启示。... 运用文献资料、逻辑分析等研究方法,围绕青少年体质健康监测政策协同展开研究,从美国的市场化与多元主体协同体系,日本的政府主导与家庭、学校、社区联合监测模式以及俄罗斯新版“劳卫制”下的政策协同与组织过程保障模式中得到启示。研究认为,青少年体质健康监测政策协同具有主体多元、政府主导、过程渐进、效果有限等时代特征,应在“社会-学校-国家”关系视角下协同推进体医融合,培育核心素养。在社会层面促进多元主体参与,跨部门推动体医融合政策协同;在学校层面以“教学-监测”双循环同向发力培育核心素养;在国家层面优化制度设计,引入“政府主导-市场监督-家长监督”全监督链条,构建管理创新机制,推动青少年体质健康监测政策协同。 展开更多
关键词 青少年 体质健康监测 政策协同 域外经验 体医融合
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大凉山背斜核部区隧道初支大变形机理与控制 被引量:1
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作者 梁斌 陈诺 +1 位作者 苗景川 李文杰 《河南科技大学学报(自然科学版)》 北大核心 2024年第2期78-86,M0007,共10页
针对大凉山2号公路隧道穿越高地应力背斜核心区域,隧道易发生初支大变形、坍塌、钢架扭曲等问题,通过现场监控量测、围岩岩性实验、理论分析、数值模拟分析和围岩接触压力监测等综合分析,研究了大凉山2号隧道背斜核部大变形成因机理。... 针对大凉山2号公路隧道穿越高地应力背斜核心区域,隧道易发生初支大变形、坍塌、钢架扭曲等问题,通过现场监控量测、围岩岩性实验、理论分析、数值模拟分析和围岩接触压力监测等综合分析,研究了大凉山2号隧道背斜核部大变形成因机理。研究表明:背斜核部玄武岩单轴抗压强度为23.31 MPa,凝灰质泥岩遇水具有一定膨胀性,给围岩变形创造了条件。由于岩层岩性不同,开挖后洞周玄武岩呈独立受弯剪梁状态。相对无水条件下,受地下水补给影响,围岩塑性区面积增加,拱腰部位较为明显。加固前,拱顶沉降量最大达470 mm,拱腰最大收敛值为844 mm,围岩接触压力为523.47 kPa。采用双层小导管+中台阶临时支撑+边墙临时支撑的“主动适应+强支撑”的综合处置方式,隧道拱顶变形减少87.6%,水平收敛变形减少95%,围岩接触压力最大值降至128 kPa,隧道变形得到有效控制。 展开更多
关键词 隧道工程 背斜核部区 大变形机理 现场监测 岩性实验 数值模拟
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基于Raman光谱的3,5-二氨基-1,2,4-三唑(DAT)合成反应在线监测与反应机理探究——推荐一个仪器分析综合实验
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作者 张天龙 张容玲 +2 位作者 汤宏胜 李延 李华 《大学化学》 CAS 2024年第6期303-311,共9页
本实验介绍了一个仪器分析综合性实验——基于Raman光谱的3,5-二氨基-1,2,4-三唑(DAT)合成的在线监测与反应机理探究。该实验是一个科研转化的仪器分析综合实验,内容包括DAT的合成、基于Raman光谱的合成反应过程在线监测以及合成反应机... 本实验介绍了一个仪器分析综合性实验——基于Raman光谱的3,5-二氨基-1,2,4-三唑(DAT)合成的在线监测与反应机理探究。该实验是一个科研转化的仪器分析综合实验,内容包括DAT的合成、基于Raman光谱的合成反应过程在线监测以及合成反应机理解析。在实验中,采用化学计量学方法对Raman光谱数据进行处理和分析,以更深入地理解合成反应的机理。通过本实验,可以巩固学生的化学专业知识,提高学生的综合实验操作技能,激发学生对科学研究的兴趣,培养学生的科研探究能力。 展开更多
关键词 拉曼光谱 在线监测 合成反应机理 综合实验
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