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Application of Connected Truck Data to Evaluate Spatiotemporal Impact of Rest Area Closures on Ramp Parking
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作者 Jijo K. Mathew Jairaj Desai +1 位作者 Edward D. Cox Darcy M. Bullock 《Journal of Transportation Technologies》 2024年第3期289-307,共19页
Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck s... Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure. 展开更多
关键词 Connected Truck data Rest areas Exit Ramps Truck Parking Commercial Vehicles
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Priority Based Energy Efficient MAC Protocol by Varying Data Ratefor Wireless Body Area Network
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作者 R.Sangeetha Usha Devi Gandhi 《Computer Systems Science & Engineering》 2024年第2期395-411,共17页
Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor ... Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor human physical parameters such as temperature,blood pressure,pulse rate,oxygen level,body motion,and so on.They sense the data and communicate it to the Body Area Network(BAN)Coordinator.The main challenge for the WBAN is energy consumption.These issues can be addressed by implementing an effective Medium Access Control(MAC)protocol that reduces energy consumption and increases network lifetime.The purpose of the study is to minimize the energy consumption and minimize the delay using IEEE 802.15.4 standard.In our proposed work,if any critical events have occurred the proposed work is to classify and prioritize the data.We gave priority to the highly critical data to get the Guarantee Tine Slots(GTS)in IEEE 802.15.4 standard superframe to achieve greater energy efficiency.The proposed MAC provides higher data rates for critical data based on the history and current condition and also provides the best reliable service to high critical data and critical data by predicting node similarity.As an outcome,we proposed a MAC protocol for Variable Data Rates(MVDR).When compared to existing MAC protocols,the MVDR performed very well with low energy intake,less interruption,and an enhanced packet-sharing ratio. 展开更多
关键词 Wireless Body area Network(WBAN) IEEE 802.15.4 energy efficiency MAC protocol ZIGBEE
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DNBP-CCA:A Novel Approach to Enhancing Heterogeneous Data Traffic and Reliable Data Transmission for Body Area Network
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作者 Abdulwadood Alawadhi Mohd.Hasbullah Omar +3 位作者 Abdullah Almogahed Noradila Nordin Salman A.Alqahtani Atif M.Alamri 《Computers, Materials & Continua》 SCIE EI 2024年第5期2851-2878,共28页
The increased adoption of Internet of Medical Things (IoMT) technologies has resulted in the widespread use ofBody Area Networks (BANs) in medical and non-medical domains. However, the performance of IEEE 802.15.4-bas... The increased adoption of Internet of Medical Things (IoMT) technologies has resulted in the widespread use ofBody Area Networks (BANs) in medical and non-medical domains. However, the performance of IEEE 802.15.4-based BANs is impacted by challenges related to heterogeneous data traffic requirements among nodes, includingcontention during finite backoff periods, association delays, and traffic channel access through clear channelassessment (CCA) algorithms. These challenges lead to increased packet collisions, queuing delays, retransmissions,and the neglect of critical traffic, thereby hindering performance indicators such as throughput, packet deliveryratio, packet drop rate, and packet delay. Therefore, we propose Dynamic Next Backoff Period and Clear ChannelAssessment (DNBP-CCA) schemes to address these issues. The DNBP-CCA schemes leverage a combination ofthe Dynamic Next Backoff Period (DNBP) scheme and the Dynamic Next Clear Channel Assessment (DNCCA)scheme. The DNBP scheme employs a fuzzy Takagi, Sugeno, and Kang (TSK) model’s inference system toquantitatively analyze backoff exponent, channel clearance, collision ratio, and data rate as input parameters. Onthe other hand, the DNCCA scheme dynamically adapts the CCA process based on requested data transmission tothe coordinator, considering input parameters such as buffer status ratio and acknowledgement ratio. As a result,simulations demonstrate that our proposed schemes are better than some existing representative approaches andenhance data transmission, reduce node collisions, improve average throughput, and packet delivery ratio, anddecrease average packet drop rate and packet delay. 展开更多
关键词 Internet of Medical Things body area networks backoff period tsk fuzzy model clear channel assessment media access control
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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China
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作者 ZHANG Sumei ZHANG Yuan ZHAO Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第3期548-563,共16页
The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate ... The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data. 展开更多
关键词 crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen Plain China
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Arsenic and fluoride co-enrichment of groundwater in the loess areas and associated human health risks:A case study of Dali County in the Guanzhong Basin
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作者 Rui-ping Liu Fei Liu +5 位作者 Hua-qing Chen Yu-ting Yang Hua Zhu You-ning Xu Jian-gang Jiao Refaey M El-Wardany 《China Geology》 CAS CSCD 2024年第3期445-459,共15页
This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin.Key findings are as follows:(1... This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin.Key findings are as follows:(1)Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26%and 30%,respectively,of the total samples,with primary hydrochemical type identified as HCO_(3)-Na.The karst and sand areas exhibit relatively high groundwater quality,serving as preferred sources for water supply.It is recommended that local governments fully harness groundwater in these areas;(2)groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin,which represents the drainage zone of groundwater;(3)arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources;(4)the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks,which are more serious to kids compared to adults.This study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas. 展开更多
关键词 ARSENIC FLUORIDE GROUNDWATER Cancer risk Kid and adult Human health risk assessment Hydrogeological survey engineering Environmental geological survey engineering Loess areas
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Affordability, Accessibility, and Quality of Maternal Health Care Services and Level of Satisfaction of Mothers in Rural Areas in China
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作者 Teng Sun Rebecca A.Guariño 《Journal of Clinical and Nursing Research》 2024年第8期218-231,共14页
Objective:This study aimed to understand the affordability,accessibility,and quality of maternal and child health services for postpartum mothers,and their impact on satisfaction.Methods:The study utilized the Anderso... Objective:This study aimed to understand the affordability,accessibility,and quality of maternal and child health services for postpartum mothers,and their impact on satisfaction.Methods:The study utilized the Anderson model and revised the Maternal Pregnancy and Perinatal Health Service Questionnaire.A survey was conducted among 289 mothers aged 20–49 in Feicheng City.Results:Regarding accessibility,most respondents(133)reported that travel time to healthcare services exceeded 60 minutes,while 99 respondents indicated a travel time of 16–30 minutes.The issue of affordability was highlighted,with 86.85%of participants perceiving maternal healthcare services as costly,indicating a significant financial burden.More than 50%of respondents were satisfied with two specific dimensions(P<0.05)regarding the quality of maternal healthcare services.Conclusion:The study found that accessibility,affordability,and quality significantly affect mothers’satisfaction with maternal health services.Future research should focus on developing more suitable service pathways for rural mothers. 展开更多
关键词 AFFORdaBILITY ACCESSIBILITY QUALITY Maternal health care services Level of satisfaction Rural area
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东海OBN和三维DAS-VSP数据的联合采集与处理方法研究 被引量:1
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作者 张少华 苟量 +8 位作者 余刚 刘海波 张昊 曹中林 陈沅忠 何光明 吴俊军 王熙明 王艳华 《石油物探》 CSCD 北大核心 2024年第1期30-44,共15页
近年来,光纤传感技术已经应用于地面地震数据、海洋地震数据、井中地震数据和井地联合地震数据的采集,推动了光纤传感技术在地球物理特别是地震数据采集中的应用。井地或井海联合地震勘探是陆地或海洋三维地震与三维DAS-VSP勘探相结合... 近年来,光纤传感技术已经应用于地面地震数据、海洋地震数据、井中地震数据和井地联合地震数据的采集,推动了光纤传感技术在地球物理特别是地震数据采集中的应用。井地或井海联合地震勘探是陆地或海洋三维地震与三维DAS-VSP勘探相结合形成的三维立体地震勘探方法,利用井海联采的三维DAS-VSP数据,可以获得地下井周围准确的时深关系、地层速度、反褶积算子、球面扩散补偿因子、吸收衰减因子、各向异性参数和井筒周围的高分辨率构造成像,这些参数可以基于井驱处理提高陆地或海洋三维地震数据的处理质量。在中国东海某OBN数据勘探中首次开展了井下套管内铠装光缆同步采集的三维DAS-VSP数据的处理方法研究以及成像处理。首先,采用常规的三维VSP数据成像处理技术对三维DAS-VSP数据进行常规处理,具体处理流程包括:观测系统定义、预处理、初至拾取、静校正、振幅补偿、反褶积、波场分离、速度分析与建模和利用上行反射波进行井周围地层的构造成像;然后,再根据海上三维DAS-VSP数据下行多次波的特点,研发了海上三维DAS-VSP数据的下行多次波成像技术,扩展了三维DAS-VSP数据成像范围,提高了三维DAS-VSP数据成像的整体质量。与本工区早期的三维OBC数据成像结果相比,本次三维DAS-VSP数据的下行多次波成像结果表明,井周围三维构造成像质量得到了显著改进,大幅度扩展了成像范围;新采集的OBN数据和三维DAS-VSP数据的成像结果展示了更为详细和较高分辨率的构造成像,基于新的成像资料,对储层顶部和储层内流体的识别与追踪变得更加容易和清晰。井海联采技术生产效率高且成本低,既能快速获得三维DAS-VSP数据及成像,还能对三维海洋地震数据进行井驱提高分辨率处理。此外,三维OBN或OBC数据和三维DAS-VSP数据还能够进行融合处理,实现井地或井海同步采集数据的联合偏移成像,可以大幅度提高三维海洋地震数据的成像品质,值得在有条件的地方推广应用。 展开更多
关键词 光纤 分布式 daS-VSP OBN OBC 联采 多次波偏移
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采用非稳相偏振滤波的DAS-VSP数据P/S波分离方法及其应用
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作者 王腾飞 程玖兵 +3 位作者 孟涛 曹中林 胡善政 段鹏飞 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2761-2772,共12页
分布式光纤声学传感(DAS)因成本低、易布设以及高密度采样等优势正成为重要的地震观测技术,尤其是越来越多地与垂直地震剖面(VSP)结合,用于主动地震勘探或被动地震监测.DAS传感器通过感知弹性波场产生的轴向应变或应变速率来观测地震波... 分布式光纤声学传感(DAS)因成本低、易布设以及高密度采样等优势正成为重要的地震观测技术,尤其是越来越多地与垂直地震剖面(VSP)结合,用于主动地震勘探或被动地震监测.DAS传感器通过感知弹性波场产生的轴向应变或应变速率来观测地震波场振动.然而,目前单分量DAS-VSP数据未完整地记录地下弹性波场的三维矢量振动信号,因此如何从中分离出P波或S波用于后续地震成像与参数反演是重要且很有挑战的课题.以弹性波传播理论为基础,本文根据P波和S波的频散关系估算接收点处各自的偏振方向,通过随频率和空间位置变化的偏振滤波实现DAS-VSP数据的P/S波分离.理论模型合成数据与东海实际DAS-VSP数据实验结果表明,该方法能有效地将P波和S波信号从单分量DAS-VSP数据中分离出来,可为后续纵横波速度反演、PP与PS波成像提供关键的数据预条件处理. 展开更多
关键词 分布式光纤声学传感(daS) VSP P/S波分离 偏振投影 非稳相滤波
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基于“脑肠轴理论”探讨龟羚帕安丸对PD大鼠纹状体DA及血清CCK、VIP水平影响的研究
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作者 常学辉 张良芝 +2 位作者 陈帅杰 王冬莲 张创业 《四川中医》 2024年第1期80-83,共4页
目的:基于“脑肠轴理论”探讨龟羚帕安丸对PD大鼠纹状体裂解液多巴胺(Dopamine,DA)、血清胆囊收缩素(cholecystokinin,CCK)及血管活性肠肽(vasoactive intestinal peptide,VIP)水平的影响。方法:采用6-羟基多巴胺注射法制作PD大鼠模型,... 目的:基于“脑肠轴理论”探讨龟羚帕安丸对PD大鼠纹状体裂解液多巴胺(Dopamine,DA)、血清胆囊收缩素(cholecystokinin,CCK)及血管活性肠肽(vasoactive intestinal peptide,VIP)水平的影响。方法:采用6-羟基多巴胺注射法制作PD大鼠模型,随机分为模型组、西药组、中药高、中、低剂量组,每组15只,另设15只假手术组。模型组及假手术组给予等容积生理盐水灌胃,其余组给予相应药物灌胃,连续给药4周。酶联免疫吸附测定法(ELISA)检测纹状体裂解液DA及血清CCK、VIP水平。结果:模型组大鼠纹状体DA、血清CCK及VIP水平显著降低;中药各剂量组、西药组大鼠纹状体DA、血清CCK及VIP水平明显均增加(P<0.01)。结论:龟羚帕安丸具有明显神经保护作用,作用机制与激活脑肠轴、增加血清CCK及VIP水平、增加中脑黑质纹状体DA的水平、发挥改善肠道功能作用有关。 展开更多
关键词 帕金森病 龟羚帕安丸 多巴胺 胆囊收缩素 血管活性肠肽
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基于SDRS数据的钻石DA20飞机故障分析及处理
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作者 孙一 《机电信息》 2024年第16期47-49,53,共4页
基于使用困难报告系统(SDRS)对钻石DA20飞机的故障数据进行分析。基于SDRS系统收集到的数据,结合故障分类方法,对钻石DA20飞机的不同故障进行研究,并提出相应的解决措施,有利于提高钻石DA20飞机机队的可靠性和安全性。
关键词 SDRS da20飞机 故障 数据
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基于机载LiDAR技术植被茂密区小型滑坡识别与评价
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作者 陈刚 郝社锋 +4 位作者 蒋波 喻永祥 车增光 刘汉湖 杨容浩 《自然资源遥感》 CSCD 北大核心 2024年第3期196-205,共10页
山体滑坡会导致生命和财产损失,获取完整的滑坡空间分布图及对易发区域的准确判定有利于指导生产、生活和生态空间优化。在滑坡调查过程中,茂密的植被覆盖使滑坡调查难度加大,机载激光雷达(light detection and ranging,LiDAR)技术的穿... 山体滑坡会导致生命和财产损失,获取完整的滑坡空间分布图及对易发区域的准确判定有利于指导生产、生活和生态空间优化。在滑坡调查过程中,茂密的植被覆盖使滑坡调查难度加大,机载激光雷达(light detection and ranging,LiDAR)技术的穿透能力使真实地形特征得以呈现,从而实现植被茂密区滑坡识别。该文通过仿地飞行获取研究区LiDAR点云数据,基于点云数据得到数字高程模型(digital elevation model,DEM),在山体阴影分析、彩色增强显示及三维场景模拟基础上,识别出区域内已有滑坡的位置与规模,经野外核实,滑坡解译精度为86.4%。针对滑坡易发区评价问题,以现有滑坡为样本,首次采用遥感分类思维开展滑坡易发区划定,采用小区域内与滑坡发育有关的高程、坡度和地表起伏度组合成影像,以支持向量机为分类方法,判定出滑坡易发区域,经滑坡检验样本分析,滑坡识别精度为81.91%。研究表明:基于高精度的LiDAR数据及其视觉增强后的图像能识别小型滑坡,采用支持向量机分类法可以准确确定滑坡易发区,为下一步三生空间规划与优化提供依据。 展开更多
关键词 LIdaR 滑坡 山体阴影 支持向量机 滑坡易发性评价
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Multi-source Data-driven Identification of Urban Functional Areas:A Case of Shenyang,China 被引量:3
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作者 XUE Bing XIAO Xiao +2 位作者 LI Jingzhong ZHAO Bingyu FU Bo 《Chinese Geographical Science》 SCIE CSCD 2023年第1期21-35,共15页
Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of ... Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of human-land interaction.In this paper,based on multi-source big data include 250 m×250 m resolution cell phone data,1.81×105 Points of Interest(POI)data and administrative boundary data,we built a UFA identification method and demonstrated empirically in Shenyang City,China.We argue that the method we built can effectively identify multi-scale multi-type UFAs based on human activity and further reveal the spatial correlation between urban facilities and human activity.The empirical study suggests that the employment functional zones in Shenyang City are more concentrated in central cities than other single functional zones.There are more mix functional areas in the central city areas,while the planned industrial new cities need to develop comprehensive functions in Shenyang.UFAs have scale effects and human-land interaction patterns.We suggest that city decision makers should apply multi-sources big data to measure urban functional service in a more refined manner from a supply-demand perspective. 展开更多
关键词 human-land relationship multi-source big data urban functional area identification method Shenyang City
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Chemical Composition of Sphyraena barracuda with Different Area, Size and Season, in Sudanese Red Sea Coast
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作者 Hala Gindeel A. Ahmadoon Abdall N. Elawad +1 位作者 Alamin M. Alamin Adam A. Babiker 《Food and Nutrition Sciences》 CAS 2023年第5期415-420,共6页
This study aims to determine the effect of area, size and season on chemical composition of Sphyraena barracuda from Sudanese Red Sea Coast. A total of 180 fish samples were collected from Port Sudan and Sawakin fishi... This study aims to determine the effect of area, size and season on chemical composition of Sphyraena barracuda from Sudanese Red Sea Coast. A total of 180 fish samples were collected from Port Sudan and Sawakin fishing sites during the winter and summer of 2020-2021. The fishes sample ranged between (30 - 50) cm in total length and (250 - 1000) gm in body weight of small size, and ranged between (60 - 90) cm in total length and (1250 - 250) gm in body weight for large size. Fish flesh was subject to gross chemical analysis. Moisture, protein, fat, ash, acidity and pH were determined. The results indicated a significant effect by area, season and size. The different areas had a significant effect on crude protein and ash;higher parameter value is found in Sawakin. Higher chemical parameters were showed in winter than in summer. Also, size had a significant effect in all parameters (except moisture), fat and ash were high in large size. The study has concluded that the large size fishes of S. barracuda with high nutritional value when caught in winter from the southern region of Sawakin. 展开更多
关键词 area Chemical Composition Season and Size
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Ecological-Based Mining:A Coal-Water-Thermal Collaborative Paradigm in Ecologically Fragile Areas in Western China 被引量:2
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作者 Xiaoxiu Liu Yifan Zeng +3 位作者 Qiang Wu Shihao Meng Jiyue Liang Zhuping Hou 《Engineering》 SCIE EI CAS CSCD 2024年第7期209-222,共14页
A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achievin... A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources essential.Based on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is proposed.An integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological storage.An active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water inrush.By implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal mining.An integrated-energy complementary model that incorporates the clean production concept of heat utilization is also proposed.The findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2%and a notable 24.2%reduction in carbon emissions.The ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenting a viable method for mine-water management in the Ordos Basin and providing insights for green and low-carbon mining. 展开更多
关键词 Dual carbon targets Coal-water-thermal co-mining Ecologically fragile areas Mine-water control Resource utilization
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Correlation of periodontal inflamed surface area with glycated hemoglobin,interleukin-6 and lipoprotein(a)in type 2 diabetes with retinopathy 被引量:3
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作者 Nusreen Jamal Thazhe Poyil Rosamma Joseph Vadakkekuttical Chandni Radhakrishnan 《World Journal of Diabetes》 SCIE 2024年第4期686-696,共11页
BACKGROUND The two-way relationship between periodontitis and type 2 diabetes mellitus(T2DM)is well established.Prolonged hyperglycemia contributes to increased periodontal destruction and severe periodontitis,accentu... BACKGROUND The two-way relationship between periodontitis and type 2 diabetes mellitus(T2DM)is well established.Prolonged hyperglycemia contributes to increased periodontal destruction and severe periodontitis,accentuating diabetic complications.An inflammatory link exists between diabetic retinopathy(DR)and periodontitis,but the studies regarding this association and the role of lipoprotein(a)[Lp(a)]and interleukin-6(IL-6)in these conditions are scarce in the literature.AIM To determine the correlation of periodontal inflamed surface area(PISA)with glycated Hb(HbA1c),serum IL-6 and Lp(a)in T2DM subjects with retinopathy.METHODS This cross-sectional study comprised 40 T2DM subjects with DR and 40 T2DM subjects without DR.All subjects were assessed for periodontal parameters[bleeding on probing(BOP),probing pocket depth,clinical attachment loss(CAL),oral hygiene index-simplified,plaque index(PI)and PISA],and systemic parameters[HbA1c,fasting plasma glucose and postprandial plasma glucose,fasting lipid profile,serum IL-6 and serum Lp(a)].RESULTS The proportion of periodontitis in T2DM with and without DR was 47.5%and 27.5%respectively.Severity of periodontitis,CAL,PISA,IL-6 and Lp(a)were higher in T2DM with DR group compared to T2DM without DR group.Significant difference was observed in the mean percentage of sites with BOP between T2DM with DR(69%)and T2DM without DR(41%),but there was no significant difference in PI(P>0.05).HbA1c was positively correlated with CAL(r=0.351,P=0.001),and PISA(r=0.393,P≤0.001)in study subjects.A positive correlation was found between PISA and IL-6(r=0.651,P<0.0001);PISA and Lp(a)(r=0.59,P<0.001);CAL and IL-6(r=0.527,P<0.0001)and CAL and Lp(a)(r=0.631,P<0.001)among study subjects.CONCLUSION Despite both groups having poor glycemic control and comparable plaque scores,the periodontal parameters were higher in DR as compared to T2DM without DR.Since a bidirectional link exists between periodontitis and DM,the presence of DR may have contributed to the severity of periodontal destruction and periodontitis may have influenced the progression of DR. 展开更多
关键词 Type 2 diabetes mellitus PERIODONTITIS Periodontal inflamed surface area Glycated Hb Diabetic retinopathy
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Insights into the long-term stability of landslide dams on the eastern margin of the Tibetan Plateau, China——A case study of the Diexi area
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作者 SONG Liang WANG Yun-sheng +3 位作者 HU Dong-yu WU Hao-chen TANG Tao LIU Shi-cheng 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1674-1694,共21页
Landslide dams,especially long-term stable landslide dams,have been recognized as important contributors to regional geomorphological evolution.Here,the Diexi area,a long-term stable dam-prone area located in upstream... Landslide dams,especially long-term stable landslide dams,have been recognized as important contributors to regional geomorphological evolution.Here,the Diexi area,a long-term stable dam-prone area located in upstream of the Minjiang River on the eastern Tibetan Plateau,was adopted to reveal reasons that landslide dams are concentrated in this area and maintain long-term stability via detailed field investigations,landslide dam sampling,unmanned aerial vehicle(UAV)images,and digital surface models(DSM).The results show the controlling factors that the slopes are prone to sliding and rock mass structure deterioration including lithological combination mode,slope structure,topographic conditions,a series of NNE-trending radial fissures and hydrological conditions.Fault activities,which have caused many earthquakes,are the main inducing factor.Landslide dams are prone to occurrence in the Diexi area owing to the combined effect of the narrow channels,the large landslide dam volume and the rock fragments.The river flow,and the landslide dam volume,material,structure,and parameters control the stability of landslide dams.The landslide dam consists of various sizes of boulders and all landslide dams exhibit an obvious inverse grading sequence,and this size combination could consume most of the flow energy,and consequently protect the dam from incision.Additionally,a total of seven knickpoints were formed by landslide dams,and the longitudinal gradient upstream of every landslide dam was found to decrease by the action of knickpoint.In the eastern margin of the Tibetan Plateau,there are numerous landslide dams existed for hundreds or thousands of years.Studies on the long-term stable landslide dams in the Diexi area could provide experience for studying similar kinds of landslide dams in this region. 展开更多
关键词 Stable landslide dams Diexi area Arcuate tectonic belt EARTHQUAKE
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Research on the Relationship Between Environmental and Economic Coupling Systems in Bohai Bay Area Based on a Vector Autoregression(VAR)Model 被引量:1
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作者 CAO Huimin WANG Ping +2 位作者 ZHANG Surong XU Dongpo TIAN Weijun 《Journal of Ocean University of China》 CAS CSCD 2024年第2期557-566,共10页
This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(V... This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(VAR)model is used to analyze and forecast the short-run and long-run relationships between three industrial structures,pollutant discharge,and economic development.The results showed that the environmental index had a long-term cointegration relationship with the industrial structure economic index.Per capital chemical oxygen demand(PCOD)and per capita ammonia nitrogen(PNH_(3)N)had a positive impact on delta per capita GDP(dPGDP),while per capita solid waste(PSW),the secondary industry rate(SIR)and delta tertiary industry(dTIR)had a negative impact on dPGDP.The VAR model under this coupling system had stability and credibility.The impulse response results showed that the short-term effect of the coupling system on dPGDP was basically consistent with the Granger causality test results.In addition,variance decomposition was used in this study to predict the long-term impact of the coupling system in the next ten periods(i.e.,ten years).It was found that dTIR had a great impact on dPGDP,with a contribution rate as high as 74.35%in the tenth period,followed by the contribution rate of PCOD up to 3.94%,while the long-term contribution rates of PSW,SIR and PNH3N were all less than 1%.The results show that the government should support the development of the tertiary industry to maintain the vitality of economic development and prevent environmental deterioration. 展开更多
关键词 Bohai Bay area environmental pollution industrial structure cointegration theory VAR model impulse response
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Seismic response of a mid-story isolated structure considering SSI in mountainous areas under long-period earthquakes 被引量:1
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作者 Wan Feng Qin Shengwu +7 位作者 Liu Dewen Zhao Tiange Zheng Yanping Shan Hang Li Zhiang Peng Fusong Xu Jingran Lei Min 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期151-161,共11页
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es... At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures. 展开更多
关键词 SSI in mountainous areas long-period earthquakes mid-story isolated structure structural dynamic analysis
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长庆安塞油田剩余油开发区DAS井地联采技术探索与实践
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作者 陈策 王学刚 +3 位作者 陈浩林 代波 周丽萍 黄建华 《石油科技论坛》 2024年第3期95-103,117,共10页
中国石油集团东方地球物理勘探有限责任公司结合长庆安塞油田开发区“三低”和“双复杂”的典型特点,面对老油田剩余油预测突出问题,从井地、井震协同一体化研究思路出发,开展国内首次面向开发区剩余油预测的多井DAS三维井地联采技术探... 中国石油集团东方地球物理勘探有限责任公司结合长庆安塞油田开发区“三低”和“双复杂”的典型特点,面对老油田剩余油预测突出问题,从井地、井震协同一体化研究思路出发,开展国内首次面向开发区剩余油预测的多井DAS三维井地联采技术探索与实践,通过井地联合勘探实现地面地震测量和井中地震测量的优势互补,取得了良好成果。(1)通过井震同步井驱处理,三维地震资料保真度和分辨率明显提升,有效频带拓宽8%以上。(2)通过井地、井震一体化油藏静态描述剩余油预测研究,减少了单一地面地震解释成果多解性,可分辨更小地质单元,为油田精细开发提供了可靠的资料依据。(3)DAS三维井地联采配套技术支撑了安塞油田新增地质储量,并通过低产低效井组挖潜措施调整,提产效果明显。通过本次研究得出,井地联合立体探测是提升油田开发过程中微幅构造刻画和储层、流体预测精度的有效技术手段,形成的技术可推动物探技术向油田开发延伸、向井地立体探测发展,可为老油田稳产增效、推进高效开发提供支撑。 展开更多
关键词 井地联采 daS 剩余油预测 三维地震 安塞油田
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砂土含水率对DAS振幅响应影响的试验研究
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作者 李俊鹏 张诚成 +3 位作者 施斌 陈卓 谢涛 郭君仪 《防灾减灾工程学报》 CSCD 北大核心 2024年第2期434-441,458,共9页
利用分布式声波传感(DAS)技术和地下通讯光纤网进行周界安防(入侵)监控、管道泄漏监测、交通状况评估等是城市安全动态监测的新方向。为探究DAS监测过程中暗光纤周围岩土介质含水率变化对DAS振幅响应特性的影响,设计了小球撞击圆盘与小... 利用分布式声波传感(DAS)技术和地下通讯光纤网进行周界安防(入侵)监控、管道泄漏监测、交通状况评估等是城市安全动态监测的新方向。为探究DAS监测过程中暗光纤周围岩土介质含水率变化对DAS振幅响应特性的影响,设计了小球撞击圆盘与小球直接撞击砂土面二种激振方式下五种质量含水率0%、5%、10%、15%和20%砂土的DAS振幅响应试验。试验结果表明:(1)小球自由下落撞击砂土面激发的振动信号和传感光纤圆环布设可提高DAS信噪比,试验装置可靠性高、试验结果重复性好;(2)受砂土似黏聚力和声波传播衰减两个因素共同影响,DAS信号振幅随砂土含水率变化存在一个临界含水率。当砂土含水率小于临界含水率时,DAS信号振幅随含水率增大而减小,而当砂土含水率大于临界含水率时,DAS信号振幅随含水率增大而增大;(3)因砂土似黏聚力作用和小球撞击时能量转化的差异,小球与砂土的接触形式对DAS振幅响应有显著影响。研究结果为城市地下工程安全动态DAS精细监测提供理论依据。 展开更多
关键词 daS 砂土 含水率 振幅响应特性 似黏聚力 声波衰减
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