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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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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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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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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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Evaluation of excavation damaged zones(EDZs)in Horonobe Underground Research Laboratory(URL)
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作者 Koji Hata Sumio Niunoya +1 位作者 Kazuhei Aoyagi Nobukatsu Miyara 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期365-378,共14页
Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and disco... Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and discontinuities are created or propagate in the rock mass.Therefore,it is effective to measure and evaluate the acoustic emission(AE)events generated by the rocks,which is a small elastic vibration,and permeability change.The authors have developed a long-term measurement device that incorporates an optical AE(O-AE)sensor,an optical pore pressure sensor,and an optical temperature sensor in a single multi-optical measurement probe(MOP).Japan Atomic Energy Agency has been conducting R&D activities to enhance the reliability of high-level radioactive waste(HLW)deep geological disposal technology.In a high-level radioactive disposal project,one of the challenges is the development of methods for long-term monitoring of rock mass behavior.Therefore,in January 2014,the long-term measurements of the hydro-mechanical behavior of the rock mass were launched using the developed MOP in the vicinity of 350 m below the surface at the Horonobe Underground Research Center.The measurement results show that AEs occur frequently up to 1.5 m from the wall during excavation.In addition,hydraulic conductivity increased by 2e4 orders of magnitude.Elastoplastic analysis revealed that the hydraulic behavior of the rock mass affected the pore pressure fluctuations and caused micro-fractures.Based on this,a conceptual model is developed to represent the excavation damaged zone(EDZ),which contributes to the safe geological disposal of radioactive waste. 展开更多
关键词 Excavation damaged zone(EDZ) Optical sensor long-term monitoring Acoustic emission(AE) Shaft sinking
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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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Design of Low-Power Data Logger of Deep Sea for Long-Term Field Observation 被引量:1
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作者 赵伟 陈鹰 +2 位作者 杨灿军 曹建伟 顾临怡 《China Ocean Engineering》 SCIE EI 2009年第1期133-144,共12页
This paper describes the implementation of a data logger for the real-time in-situ monitoring of hydrothermal systems. A compact mechanical structure ensures the security and reliability of data logger when used under... This paper describes the implementation of a data logger for the real-time in-situ monitoring of hydrothermal systems. A compact mechanical structure ensures the security and reliability of data logger when used under deep sea. The data logger is a battery powered instrument, which can connect chemical sensors (pH electrode, H2S electrode, H2 electrode) and temperature sensors. In order to achieve major energy savings, dynamic power management is implemented in hardware design and software design. The working current of the data logger in idle mode and active mode is 15 μA and 1.44 mA respectively, which greatly extends the working time of battery. The data logger has been successftdly tested in the first Sino-American Cooperative Deep Submergence Project from August 13 to September 3, 2005. 展开更多
关键词 data logger low-power design deep sea long-term monitoring
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Supporting structure failure caused by the squeezing tunnel creep and its reinforcement measure 被引量:2
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作者 ZHAO Jin-peng TAN Zhong-sheng +1 位作者 LI Lei WANG Xiu-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1774-1789,共16页
Tunnels deeply buried have high crustal stress and are prone to large deformation disasters when encountering soft rock.The large deformation phenomenon during the construction process of the Maoxian Tunnel on the Che... Tunnels deeply buried have high crustal stress and are prone to large deformation disasters when encountering soft rock.The large deformation phenomenon during the construction process of the Maoxian Tunnel on the Chengdu-Lanzhou Railway is particularly evident.This article focuses on the large deformation problem of the No.1 inclined shaft of the Maoxian Tunnel,and uses on-site monitoring methods to explore the reasons for tunnel structure failure,and analyzes the mechanical behavior of the tunnel structure.By using numerical simulation methods,the effectiveness of the second-layer support in resisting creep loads in tunnels was studied,and the influence of the construction time of the secondlayer support on the mechanical properties of the tunnel was discussed.The results indicate that the first-layer support in the tunnel is a structural failure caused by asymmetric deformation caused by creep,while the second-layer support has a good effect on resisting creep loads.The research results can provide a technical reference for deformation control of squeezing tunnels. 展开更多
关键词 Squeezing tunnel Mechanical responses long-term creep Second-layer support On-site monitoring
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Political connections, media monitoring and long-term loans 被引量:4
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作者 Deming Yang Zhengfei Lu Danglun Luo 《China Journal of Accounting Research》 2014年第3期165-177,共13页
We analyze data on Chinese non-state-listed firms and find that it is easier for firms with political connections to obtain long-term loans with extended debt maturities than it is for firms without political connecti... We analyze data on Chinese non-state-listed firms and find that it is easier for firms with political connections to obtain long-term loans with extended debt maturities than it is for firms without political connections. Our investigation indicates that this phenomenon is significantly less common with increased media monitoring. Houston et al.(2011) find strong evidence that the state ownership of media is associated with higher levels of bank corruption in China, but our study shows that, to a certain extent, media monitoring can curb corruption. 展开更多
关键词 Political connections long-term loans Media monitoring
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Distinguishing the main components of submarine groundwater and estimating the corresponding fluxes based on radium tracing method—taking the Maowei Sea for example
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作者 Linwei Li Jinzhou Du +1 位作者 Xilong Wang Yanling Lao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期1-23,共23页
Submarine groundwater discharge(SGD)is an important part in the land-sea interactions,which mainly contains three components:submarine fresh groundwater discharge(SFGD),tidal flat recirculated saline groundwater disch... Submarine groundwater discharge(SGD)is an important part in the land-sea interactions,which mainly contains three components:submarine fresh groundwater discharge(SFGD),tidal flat recirculated saline groundwater discharge(tidal flat RSGD)and subtidal recirculated saline groundwater discharge(subtidal RSGD).In order to make a more accurate assessment of the impact of SGD on coastal ecological environment,it is necessary to distinguish the main components of SGD.In this study,the Maowei Sea,located in the northern part of the Beibu Gulf,was selected as the study area.Based on the radium(Ra)tracing method,we present a new analytical method for distinguishing the three main components of SGD in this area combined with field data.The average daily flow along the coastline of the Maowei Sea of tidal flat RSGD was slightly higher than that of SFGD,and both two were on the magnitude of 1×10^(5)m^(3)/d.The average daily flow for the subtidal RSGD of the entire subtidal zone of the Maowei Sea reached to the magnitude of 1×10^(6)-1×10^(7)m^(3)/d.The long-term variation trend of terrestrial SGD is a valuable information for the study of the influence of terrigenous material on the coastal ecological environment.Based on the results of four sampling periods,it is found that the fluxes of SFGD and tidal flat RSGD in the Maowei Sea had good linear correlation with the net precipitation.As an example,January 2015 to August 2022 were selected as the study periods,and the variation trends of SFGD and tidal flat RSGD were calculated by linear function with net precipitation as the independent variable.The results showed that the flux of tidal flat RSGD was slightly higher than that of SFGD,and the difference between the two is larger in flood season while smaller in dry season.In general,in the coastal range of China,the total SGD flux in the Maowei Sea area is at a high level,and the SFGD flux is at a medium level. 展开更多
关键词 submarine groundwater discharge bottom sediment radium tracing method offshore transport long-term monitoring
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REDUCTION OF NON-POINT SOURCE POLLUTION IN THE YONG'AN RIVER BY CONSTRUCTED WETLAND BASED ON 9 YEARS OF MONITORING
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作者 Huaji LIU Jian SHEN +1 位作者 Jimeng FENG Xinze WANG 《Frontiers of Agricultural Science and Engineering》 CSCD 2023年第4期627-638,共12页
The agricultural and livestock activities surrounding the rivers flowing into the lakes have caused non-point source pollution, leading to excessive amounts of nutrient salts in downstream rivers. Introducing river wa... The agricultural and livestock activities surrounding the rivers flowing into the lakes have caused non-point source pollution, leading to excessive amounts of nutrient salts in downstream rivers. Introducing river water into constructed wetlands along river course has proven to be an effective solution for decreasing nitrogen(N) and phosphorus(P) loads. This paper reports 9 years of monitoring the Yong’an River and its surrounding constructed wetlands in the upper reaches of Erhai Lake, located in Yunnan Province, China. This study analyzed the main types of pollutants in the river, and evaluated the removal efficiency of pollutants by the constructed wetlands. The findings indicate that total nitrogen(TN) and nitrate nitrogen(NO_(3)^(–)-N) are the primary pollutants in the Yong’an River, which exhibit variation throughout the year corresponding to the alternating wet and dry seasons. Although constructed wetlands are effective in removing NO_(3)^(-)-N and P, their efficacy in removing ammonium nitrogen(NH_(4)^(+)-N)and organic pollutants is limited. This limitation can be attributed to the lack of timely disposal of aquatic plant residues. This research contributes to the understanding of the potential issues that may arise during the extended use of constructed wetlands and provides solutions to address them. 展开更多
关键词 inflowing rivers surface-flow constructed wetland NUTRIENTS long-term monitoring
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Permeability evaluation for artificial single rock fracture according to geometric aperture variation using electrical resistivity 被引量:3
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作者 Hangbok Lee Jong-Won Lee Tae-Min Oh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第4期787-797,共11页
A convenient approach was proposed by which to evaluate and monitor the permeability of a rock fracture by verifying the quantitative correlation between the electrical resistivity and permeability at laboratory scale... A convenient approach was proposed by which to evaluate and monitor the permeability of a rock fracture by verifying the quantitative correlation between the electrical resistivity and permeability at laboratory scale.For this purpose,an electrical resistivity measurement system was applied to the laboratory experiments using artificial cells with the shape of a single rock fracture.Sixty experiments were conducted using rock fractures according to the geometry,aperture sizes,wavelengths,and roughness amplitudes.The overall negative relationship between the normalized electrical resistivity values and the aperture sizes directly linked with the permeability,was well fitted by the power-law function with a large determination coefficient(≈0.86).The effects of wavelength and roughness amplitude of the rock fracture on the electrical resistivity were also analyzed.Results showed that the electrical resistivity was slightly increased with decreasing wavelength and increasing roughness amplitude.An empirical model for evaluating the permeability of a rock fracture was proposed based on the experimental data.In the field,if the electrical resistivity of pore groundwater could be measured in advance,this empirical model could be applied effectively for simple,quick monitoring of the fracture permeability.Although uncertainty may be associated with the permeability estimation due to the limited control parameters considered in this research,this electrical resistivity approach could be helpful to monitor the rock permeability in deep underground facilities such as those used for radioactive waste repositories or forms of energy storage. 展开更多
关键词 PERMEABILITY Rock fracture Electrical resistivity Fracture geometry long-term monitoring
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Community-based population monitoring for large baleen whales:the case study of Bryde’s whale in Beibu Gulf of China 被引量:3
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作者 Yaoyao ZHANG Mo CHEN +5 位作者 Mao CHEN Yi HAN Yujiang HAO Kexiong WANG Zhigang MEI Ding WANG 《Integrative Zoology》 SCIE CSCD 2021年第4期626-635,共10页
Citizen science is a popular method for the long-term monitoring of the distribution of wild animals.The application of these methods in different species and environments still poses challenges,especially for aquatic... Citizen science is a popular method for the long-term monitoring of the distribution of wild animals.The application of these methods in different species and environments still poses challenges,especially for aquatic animals.In this study,we investigated the distribution of the Bryde’s whale(Balaenoptera edeni)in the Beibu Gulf of China by using scientific boat-based surveys and citizen science approaches using 2 different methods of data collection.First,we built our mobile app(Whale Guard)and installed it on fishermen’s phones.Second,we used a popular instant messaging app(WeChat)to create an online fisherman community.We found that the mobile phone app collected far fewer reports(5 reports)than the online community group(42 reports,P<0.01).By using a variety of incentives,we maintained the fisherman’s community’s activity without significant user loss(P<0.01).We also found that the locations collected by social media applications in this study were consistent with observations from scientific boat-based transect surveys.The sightings distribution of Bryde’s whales differed from those in previous surveys in that they were present across larger areas.Social media apps reported that 69%of reports was confirmed by more than one person,whereas Whale Guard reports were much lower(0,P<0.001).Community-based citizen science can greatly contribute to the long-term monitoring of Bryde’s whales,and it has successfully overcome the challenges of data accessibility,accuracy,and fragmentation.Our study shows how to appropriately use citizen science in different community groups and community-based approaches make them useful for large baleen whale surveys. 展开更多
关键词 Bryde’s whale citizen science DISTRIBUTION habitat use long-term monitoring
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Frontier of continuous structural health monitoring system for short&medium span bridges and condition assessment 被引量:3
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作者 Ayaho MIYAMOTO Risto KIVILUOMA Akito YABE 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2019年第3期569-604,共36页
It is becoming an important social problem to make maintenance and rehabilitation of existing short and medium span(10-20 m)bridges because there are a huge amount of short and medium span bridges in service in the wo... It is becoming an important social problem to make maintenance and rehabilitation of existing short and medium span(10-20 m)bridges because there are a huge amount of short and medium span bridges in service in the world.The kernel of such bridge management is to develop a method of safety(condition)assessment on items which include remaining life and load carrying capacity.Bridge health monitoring using information technology and sensors is capable of providing more accurate knowledge of bridge performance than traditional strategies.The aim of this paper is to introduce a state-of-the-art on not only a rational bridge health monitoring system incorporating with the information and communication technologies for lifetime management of existing short and medium span bridges but also a continuous data collecting system designed for bridge health monitoring of mainly short and medium span bridges.In this paper,although there are some useful monitoring methods for short and medium span bridges based on the qualitative or quantitative information,mainly two advanced structural health monitoring systems are described to review and analyse the potential of utilizing the long term health monitoring in safety assessment and management issues for short and medium span bridge.The first is a special designed mobile in-situ loading device(vehicle)for short and medium span road bridges to assess the structural safety(performance)and derive optimal strategies for maintenance using reliability based method.The second is a long term health monitoring method by using the public buses as part of a public transit system(called bus monitoring system)to be applied mainly to short and medium span bridges,along with safety indices,namely,"characteristic deflection"which is relatively free from the influence of dynamic disturbances due to such factors as the roughness of the road surface,and a structural anomaly parameter. 展开更多
关键词 condition assessment short&medium span BRIDGE structural health monitoring(SHM) long-term data collection system maintenance BRIDGE performance information technology LOADING vehicle(public bus) in-situ LOADING
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Building African Ecosystem Research Network for Sustaining Local Ecosystem Goods and Services 被引量:1
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作者 Armand Sedami Igor YEVIDE WU Bingfang +3 位作者 YU Xiubo LI Xiaosong LIU Yu LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2015年第4期414-425,共12页
A new form of producing and sharing knowledge has emerged as an international(United States of America,Asia,and Europe) research collaboration,known as the Long-Term Ecological Research(LTER) Network.Although Africa b... A new form of producing and sharing knowledge has emerged as an international(United States of America,Asia,and Europe) research collaboration,known as the Long-Term Ecological Research(LTER) Network.Although Africa boasts rich biodiversity,including endemic species,it lacks the long-term initiatives to underpin sustainable biodiversity managements.At present,climate change may exacerbate hunger and poverty concerns in addition to resulting in ecosystem degradation,land use change,and other threats in Africa.Therefore,ecosystem monitoring was suggested to understanding the effects of climate change and setting strategies to mitigate these changes.This paper aimed to investigate ecosystem monitoring ground sites and address their coverage gaps in Africa to provide a foundation for optimizing the African Ecosystem Research Network(AERN) ground sites.The geographic coordinates and characteristics of ground sites-based ecosystem monitoring were collected from various networks aligned with the LTER implementation in Africa.Additionally,climatic data and biodiversity distribution maps were retrieved from various sources.These data were used to assess the size of existing ground sites and the gaps in description,ecosystems and biomes.The results reveal that there were 1089 sites established by various networks.Among these sites,30.5%,27.5%,and 28.8% had no information of area,year of establishment,current status,respectively.However,68.0% of them had an area equal to or greater than 1 km2.Sites were created progressively over the course of the years,with 68.9% being created from 2000 to 2005.To date,only 41.5% of the sites were operational.The sites were scattered across Africa,but they were concentrated in Eastern and Southern Africa.The unbalanced distribution pattern of the sites left Central and Northern Africa hardly covered,and many unique ecosystems in Central Africa were not included.To sustain these sites,the AERN should be based on operational sites,seeking secure funding by establishing multiple partnerships. 展开更多
关键词 ecosystem monitoring long-term Ecological Research(LTER) biodiversity ground site gap analysis network Africa
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Engineering-Geological Problems in the Moravian Karst,Czech Republic
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作者 Milena AMALIKOVA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第3期303-307,共5页
The Moravian karst belongs to one of the famous karst regions in Central Europe. It is situated in Moravia in the eastern part of the Czech Republic. According to the geology it is of Devonian age and the main rocks a... The Moravian karst belongs to one of the famous karst regions in Central Europe. It is situated in Moravia in the eastern part of the Czech Republic. According to the geology it is of Devonian age and the main rocks are of different types of limestones. The process of karstification is still active. They are many caves with rich stalagmites and stalactites and the Macocha abyss, the depth of which is 138.5 m. The underground Punkva River flows through the main part of the karst, forming beautiful underground lakes. Typical karst phenomena, such as sinkholes and deep canyons, may be observed on the surface of the terrain. Because of the karstification, water erosion and frost weathering, many steep unstable slopes and walls originated. To solve the stability from a geotechnical point of view is not easy. This requests a special engineering-geological knowledge and experience. 展开更多
关键词 Czech Republic Moravian karst engineering geology slope stability long-term monitoring
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Yearly variation in the structure and diversity of a non-breeding passerine bird community in a Mediterranean wetland
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作者 Juan Arizaga Daniel Alonso +5 位作者 ArinCrespo Xabier Esparza Efrén Fernández Iógo López David Martín Antonio Vilches 《Avian Research》 CSCD 2020年第3期238-245,共8页
Background:The dynamics and structure of many bird communities are changing due to the global warming and changes in the land use and management.The Ebro Valley constitutes one of the chief wintering areas for several... Background:The dynamics and structure of many bird communities are changing due to the global warming and changes in the land use and management.The Ebro Valley constitutes one of the chief wintering areas for several passerine species in Iberia,and the reed beds spread across this Valley concentrate huge numbers of birds that use them to roost,while the surrounding agricultural areas serve as main foraging habitats.The aims of this work are(1)to quantify how variable a non-breeding passerine bird community associated to a reed bed area in the Ebro Valley is,and,(2)to test for the effect of weather on possible annual fluctuations in species’proportions at a regional/local scale.Methods:We used for that ringing data collected at Badina de Escudera lagoon(Navarra)over a 12-year period.Results:Though,overall,the assemblage did not vary strongly among years(most similarity values were>0.8),we still found a significant linear effect of year on the proportion of captures of Reed Buntings(Emberiza schoeniclus),i.e.,the dominant species detected in our passerine community.The increasing loss of weight of Reed Buntings in the community was due to a progressive decrease in its abundance.Conclusions:The structure and diversity of passerine community in Badina Escudera was not influenced by meteorological conditions at a local scale,suggesting that local weather would not have an impact on numbers of Reed Buntings in winter. 展开更多
关键词 Navarra Emberiza schoeniclus RINGING long-term monitoring
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