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A Moving Mesh Method for the Euler Flow Calculations Using a Directional Monitor Function 被引量:2
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作者 Hua-Zhong Tang 《Communications in Computational Physics》 SCIE 2006年第4期656-676,共21页
This paper is concerned with the adaptive grid method for computations of the Euler equations in fluid dynamics.The new feature of the present moving mesh algorithm is the use of a dimensional-splitting type monitor f... This paper is concerned with the adaptive grid method for computations of the Euler equations in fluid dynamics.The new feature of the present moving mesh algorithm is the use of a dimensional-splitting type monitor function,which is to increase grid concentration in regions containing shock waves and contact discontinuities or their interactions.Several two–dimensional flow problems are computed to demonstrate the effectiveness of the present adaptive grid algorithm. 展开更多
关键词 Euler equations adaptive grid method finite volume method monitor function
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Monitoring Brain and Spinal Cord Metabolism and Function 被引量:1
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作者 Pierre Pandin Marie Renard +2 位作者 Alessia Bianchini Philippe Desjardin Luc Van Obbergh 《Open Journal of Anesthesiology》 2014年第6期131-152,共22页
Monitoring the metabolism and function of the central nervous system not only is an old idea but also is a topic that is of increasing interest to the technological evolution. Beside the optimization of cerebral and s... Monitoring the metabolism and function of the central nervous system not only is an old idea but also is a topic that is of increasing interest to the technological evolution. Beside the optimization of cerebral and spinal cord perfusion and the preservation of vasoreactivity to ensure the viability of cerebral tissues and structures, we want to know more and more about the real intimate situation of these organs in real time at the patient’s bedside. To this end, several tracks have been explored during the two last decades, leading to the development of numerous concepts and the conception of various monitoring systems. One of the main problems is to characterize the respective strong points and weaknesses of those ones and to conclude regarding their individual relevance and value in current clinical practice. It is more and more clear that the combination of different categories of monitoring is a way to try to find the most valuable technological compromise, to increase the chance of prediction or of early detection of intercurrent deleterious events corresponding to the concept of multimodality. The intraoperative period and the intensive care goals and targets are appreciably different. This is the reason for the attempt to define different and distinct sets of goals and targets for the intraoperative anesthetic setting and for the intensive care unit. 展开更多
关键词 BRAIN CENTRAL Nervous System monitorING METABOLISM function
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Performance Monitoring of the Data-driven Subspace Predictive Control Systems Based on Historical Objective Function Benchmark 被引量:3
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作者 王陆 李柠 李少远 《自动化学报》 EI CSCD 北大核心 2013年第5期542-547,共6页
关键词 预测控制系统 性能监控 数据驱动 子空间 历史 基准 监视控制器 目标函数
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Stable oligonucleotide-functionalized gold nanosensors for environmental biocontaminant monitoring 被引量:2
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作者 Maria V.Riquelme Weinan Leng +2 位作者 Marcos Carzolio Amy Pruden Peter Vikesland 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第12期49-59,共11页
The global propagation of environmental biocontaminants such as antibiotic resistant pathogens and their antibiotic resistance genes(ARGs) is a public health concern that highlights the need for improved monitoring ... The global propagation of environmental biocontaminants such as antibiotic resistant pathogens and their antibiotic resistance genes(ARGs) is a public health concern that highlights the need for improved monitoring strategies. Here, we demonstrate the environmental stability and applicability of an oligonucleotide-functionalized gold nanosensor. The mec A ARG was targeted as model biocontaminant due to its presence in clinically-relevant pathogens and to its emergence as an environmental contaminant.mec A-specific nanosensors were tested for antibiotic resistance gene(ARG) detection in ARG-spiked effluent from four wastewater treatment plants(WWTPs). The mec A-specific nanosensors showed stability in environmental conditions and in high ionic strength([MgCl_2] 〈 50 m M), and high selectivity against mismatched targets. Spectrophotometric detection was reproducible with an LOD of 70 pM(≈ 4 × 10~7 genes/μL), even in the presence of interferences associated with non-target genomic DNA and complex WWTP effluent. This contribution supports the environmental applicability of a new line of cost-effective, field-deployable tools needed for wide-scale biocontaminant monitoring. 展开更多
关键词 Stable oligonucleotide-functionalized gold nanosensors for environmental biocontaminant monitoring LOD DNA
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Clinical Study on Evaluation of Autonomic Nervous Dysfunction Based on Imaging Urodynamic Examination with Slow Filling and Synchronous Blood Pressure Monitoring in the Patients with Cervicothoracic Spinal Cord Injury
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作者 Qingqing Li Hui Chen +4 位作者 Xihui Xiao Weibin Zeng Shuqing Wu Maping Huang Xinghua Yang 《Open Journal of Urology》 2021年第4期112-123,共12页
<strong>Objective:</strong> Explore the rule of autonomic nervous dysfunction in the patients with urination disorder after high level spinal cord injury, and seek a safe, objective and accurate method to ... <strong>Objective:</strong> Explore the rule of autonomic nervous dysfunction in the patients with urination disorder after high level spinal cord injury, and seek a safe, objective and accurate method to evaluate autonomic nervous function. <strong>Patients and Method:</strong> 48 patients with dysuria after cervicothoracic SCI were selected. Before, during and after imaging urodynamic examination with slow filling in supine position, blood pressure and ECG were monitored simultaneously. The symptoms of sweating, shivering, headache, flushing and chills were observed and recorded. The study of the relationship among the changes of blood pressure, heart rate and urodynamic indexes and the above symptoms was analyzed. <strong>Results:</strong> They were divided into three groups: group A (no obvious abnormality), group B (hyperactivity) and group C (hypoactivity) according to their BP, HR and existing the symptoms or not. <strong>Conclusion:</strong> The incidence of autonomic dysfunction in the high level SCI patients with dysuria was very high (79.17%), most of them were hyperactivity, and a few were low function. The changes of SBP and DBP in the hypoactivity group all appeared an increasing and then declining trend, while the change of HR in the low function one was lower than normal and decreased continuously. The main inducements of AD are neurogenic detrusor overactivity, detrusor sphincter dyssynergia, elevated abdominal pressure and abnormal bladder sensitivity. The asymptomatic patients had a higher occurrence rate (43.75%). Only by imaging urodynamic examination with slow filling and synchronous blood pressure monitoring, can autonomic nervous function of the patients be evaluated safely, objectively, early and accurately. 展开更多
关键词 High Level Spinal Cord Injury Autonomic Nervous function Imaging Urodynamic Examination Slow Filling Synchronous Blood Pressure monitoring
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基于紫玉米芯衍生的花青素复合纤维素双功能气凝胶的制备及其应用
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作者 仲若凡 王文亮 +4 位作者 郝佳琪 郑昕怡 程进宝 段秀凤 李新平 《陕西科技大学学报》 北大核心 2026年第1期7-14,共8页
本研究通过提取紫玉米芯中的纤维素和花青素,结合肉桂精油@β-环糊精包合物,构建具有pH响应显色与抗菌保鲜的双功能气凝胶.研究发现气凝胶的三维多孔网络结构赋予其优异力学性能,压缩应力达5.9 MPa(应变90%).相较于对照组纤维素膜材料,... 本研究通过提取紫玉米芯中的纤维素和花青素,结合肉桂精油@β-环糊精包合物,构建具有pH响应显色与抗菌保鲜的双功能气凝胶.研究发现气凝胶的三维多孔网络结构赋予其优异力学性能,压缩应力达5.9 MPa(应变90%).相较于对照组纤维素膜材料,双功能气凝胶的pH响应速率更快,其稳态色差值约为纤维素膜材料的1.25倍.负载肉桂精油@β-环糊精包合物气凝胶的DPPH自由基清除率衰减速率(12.48%/60 h)显著优于游离精油体系(28.25%/60 h),缓释效率提升55%.应用实验表明,双功能气凝胶对虾的新鲜度监测具有更显著的响应性及保鲜作用.本研究为从农业废弃物中获取海鲜食品新鲜度监测和保鲜材料提供了理论依据. 展开更多
关键词 紫玉米芯 新鲜度监测 食品保鲜 功能性包装材料
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基于YOLOv5-Lite的农田边界行人检测系统
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作者 林宏宇 邱培涛 +2 位作者 刘小强 张德志 李庆 《农机化研究》 北大核心 2026年第2期225-234,共10页
在农业机械作业场景中,静态障碍物相对容易实现规避,而行人这类动态障碍物的避让却存在较大难度。基于视觉的检测方法具备成本低、时效高的优势,其中YOLO算法在检测速度与实时性方面表现突出,能够在保障精度的同时维持较高的检测速率。... 在农业机械作业场景中,静态障碍物相对容易实现规避,而行人这类动态障碍物的避让却存在较大难度。基于视觉的检测方法具备成本低、时效高的优势,其中YOLO算法在检测速度与实时性方面表现突出,能够在保障精度的同时维持较高的检测速率。为此,选取YOLOv5-Lite作为核心算法,构建农田边界行人检测系统,旨在对农田边缘实现快速识别,保障农机作业安全。系统借助摄像头采集农田区域视频数据,运用区域分割算法界定农田与非农田边界,依托YOLOv5-Lite算法识别入侵者,再通过区域判别与警报算法对行人发出警示,有效防范农作物受损,守护作业安全。数据集源于卡内基梅隆大学开源数据集和自制数据集,原模型精确率95.1%、召回率51.2%,引入Mish激活函数后,精确率提升至96.6%、召回率提升至52.0%。测试结果显示:算法运行平均帧率为8.54 f/s,树莓派CPU温度达54.53℃,在多场景下检测效果良好,具备实际应用价值。 展开更多
关键词 行人检测 YOLOv5-Lite 区域分割 Mish激活函数 实时监控 农田边界
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Immune monitoring post liver transplant 被引量:13
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作者 Siddharth Sood Adam G Testro 《World Journal of Transplantation》 2014年第1期30-39,共10页
Many of the causes of short and late morbidity following liver transplantation are associated with immunosuppression or immunosuppressive medications. Current care often involves close monitoring of liver biochemistry... Many of the causes of short and late morbidity following liver transplantation are associated with immunosuppression or immunosuppressive medications. Current care often involves close monitoring of liver biochemistry as well as therapeutic drug levels. However, the postoperative course following liver transplantation can often be associated with significant complications including infection and rejection, suggesting an inadequacy in current immune function monitoring. Many assays have been tested in the research setting to identify possible biomarkers that may be used to predict clinical events such as acute cellular rejection, and therefore allow modification of a patient's immunosuppressive regimen prior to a clinical event. However, these generally require significant laboratory processing and have had difficulty becoming established in common clinical use outside the research setting. One assay, Cylex ImmuK now has been food and drug administration approved but has had variable results. In this review we discuss the assays that have been used to assess monitoring of immune function after liver transplantation and consider possible future directions. 展开更多
关键词 IMMUNE function monitoring REVIEW Biomarkers LIVER TRANSPLANTATION
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超声监测结合丁苯酞氯化钠对脑梗死介入治疗后再闭塞风险及神经功能恢复的影响研究
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作者 黄津 霍旭宁 +2 位作者 张瑞燕 李利峰 张赛 《中国现代医学杂志》 2026年第1期16-21,共6页
目的 探讨超声监测结合丁苯酞氯化钠对脑梗死介入治疗后再闭塞风险及神经功能恢复的影响。方法 选取2023年3月-2025年3月在邢台市中心医院接受脑梗死介入治疗的92例患者作为研究对象。按照随机数字表法分为对照组与观察组,各46例。对照... 目的 探讨超声监测结合丁苯酞氯化钠对脑梗死介入治疗后再闭塞风险及神经功能恢复的影响。方法 选取2023年3月-2025年3月在邢台市中心医院接受脑梗死介入治疗的92例患者作为研究对象。按照随机数字表法分为对照组与观察组,各46例。对照组采用丁苯酞氯化钠治疗;观察组在对照组基础上联合超声检测。比较两组溶栓后血管再闭塞发生率、神经功能指标、血流动力学参数、神经损伤与修复标志物。结果 观察组血管再闭塞发生率低于对照组(P<0.05)。观察组治疗前后美国国立卫生研究院卒中量表、改良Rankin量表的评分差值均大于对照组(P<0.05)。观察组术前与术后24 h的脑血流量、脑血容量、平均通过时间差值均高于对照组(P<0.05)。观察组治疗前后血清胶质纤维酸性蛋白、钙结合蛋白B、神经元特异性烯醇化酶水平差值均大于对照组(P<0.05)。结论 超声监测结合丁苯酞氯化钠可有效降低脑梗死介入治疗后的再闭塞风险,促进神经功能恢复,改善脑血流灌注,有利于临床推广应用。 展开更多
关键词 脑梗死 介入治疗 超声监测 丁苯酞氯化钠 再闭塞 神经功能
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Expert consensus on the monitoring and treatment of sepsis-induced immunosuppression
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作者 Fei Pei Ren‑Qi Yao +31 位作者 Chao Ren Soheyl Bahrami Timothy RBilliar Irshad HChaudry De‑Chang Chen Xu‑Lin Chen Na Cui Xiang‑Ming Fang Yan Kang Wei‑Qin Li Wen‑Xiong Li Hua‑Ping Liang Hong‑Yuan Lin Ke‑Xuan Liu Ben Lu Zhong‑Qiu Lu Marc Maegele Tian‑Qing Peng You Shang Lei Su Bing‑Wei Sun Chang‑Song Wang Jian Wang Jiang‑Huai Wang Ping Wang Jian‑Feng Xie Li‑Xin Xie Li‑Na Zhang Basilia Zingarelli Xiang‑Dong Guan Jian‑Feng Wu Yong‑Ming Yao 《Military Medical Research》 SCIE CAS CSCD 2023年第3期281-298,共18页
Emerged evidence has indicated that immunosuppression is involved in the occurrence and development of sepsis.To provide clinical practice recommendations on the immune function in sepsis,an expert consensus focusing ... Emerged evidence has indicated that immunosuppression is involved in the occurrence and development of sepsis.To provide clinical practice recommendations on the immune function in sepsis,an expert consensus focusing on the monitoring and treatment of sepsis-induced immunosuppression was developed.Literature related to the immune monitoring and treatment of sepsis were retrieved from PubMed,Web of Science,and Chinese National Knowledge Infrastructure to design items and expert opinions were collected through an online questionnaire.Then,the Delphi method was used to form consensus opinions,and RAND appropriateness method was developed to provide consistency evaluation and recommendation levels for consensus opinions.This consensus achieved satisfactory results through two rounds of questionnaire survey,with 2 statements rated as perfect consistency,13 as very good consistency,and 9 as good consistency.After summarizing the results,a total of 14 strong recommended opinions,8 weak recommended opinions and 2 non-recommended opinions were produced.Finally,a face-to-face discussion of the consensus opinions was performed through an online meeting,and all judges unanimously agreed on the content of this consensus.In summary,this expert consensus provides a preliminary guidance for the monitoring and treatment of immunosuppression in patients with sepsis. 展开更多
关键词 SEPSIS Immune function monitoring Immunomodulatory therapy IMMUNOSUPPRESSION
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THE DESIGN AND APPLICATION OF RELAXANT MONITORING SYSTEM
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作者 Zhou Wei Yang Jieqiu +3 位作者 Lin Shujuan Li Yuejie Wang Yuehua Wang Qiang(Inst. of Biomedical Engineering,CAMS,Tianjin 300192,China)Sun Jialan(Tianjin First Centrol Hospital,Tianjin 300192,China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1998年第1期19-21,共3页
The paper introduces a monitoring system of muscle relaxant actionduring the anaesthesia operation,which is based on measurement of acceleration.The monitor consists of an acceleration transducer,a nerve stimlation an... The paper introduces a monitoring system of muscle relaxant actionduring the anaesthesia operation,which is based on measurement of acceleration.The monitor consists of an acceleration transducer,a nerve stimlation and a microcomputer unit.The transducer can be fastened to the thumb,and the signal of thethumb movement in response to ulnar nerve stimulation is measured and registeredin the computing unit. In daily clinical practice it has proved possible,using this newapparatus, to achieve reliable evaluation of nuromuscular transimission functionand to contribute to improve anesthesia quality and patient care. 展开更多
关键词 MUSCLE relaxant NEUROMUSCULAR TRANSMISSION function monitor
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Deployment of Hash Function to Enhance Message Integrity in Wireless Body Area Network (WBAN)
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作者 Ahmed Alzubi Arif Sari 《International Journal of Communications, Network and System Sciences》 2016年第12期613-621,共10页
Message integrity is found to prove the transfer information of patient in health care monitoring system on the human body in order to collect and communicate the human personal data. Wireless body area network (WBAN)... Message integrity is found to prove the transfer information of patient in health care monitoring system on the human body in order to collect and communicate the human personal data. Wireless body area network (WBAN) applications are the fast growing technology trend but security and privacy are still largely ignored, since they are hard to achieve given the limited computation and energy resources available at sensor node level. In this paper, we propose simple hash based message authentication and integrity code algorithm for wireless sensor networks. We test the proposed algorithm in MATLAB on path loss model around the human body in two scenarios and compare the result before and after enhancement and show how sensors are connected with each other to prove the message integrity in monitoring health environment. 展开更多
关键词 Message Integrity WBAN Security Health Care monitoring System Hash function Path Loss
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THE RELATIONSHIP BETWEEN THE SPONTANEOUS NOCTURNALEPISODES OF ALKALINIZATION AND AUTONOMIC NERVOUS FUNCTION ON FD PATIENTS
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作者 张茹 龚均 +3 位作者 宋安琪 王磊 王学勤 朱有玲 《Academic Journal of Xi'an Jiaotong University》 2000年第1期37-39,66,共4页
Objective To study the relationshlp between the spontaneous nocturnal eplsodes of alkaiinization and the autonomic nerve system function and vagal function-Methods 24-hour intragastric pH was measured and autonomic an... Objective To study the relationshlp between the spontaneous nocturnal eplsodes of alkaiinization and the autonomic nerve system function and vagal function-Methods 24-hour intragastric pH was measured and autonomic and vagal function was measured with the time domain analyses of heart rate variability in 2o patients with functional dyspepsia but without diseases of the cardiovascular system- Results 13 of 2o had the nocturnal episodes of alkalinization. The to tal 24-hour SDNN and MSSD were normal in 2o subjects with FD. There was no signiflcant difference (P>O. O5) in the comparison of the total SDNN and rMSSD of the 2 groups with alkalinization and without alkalinization. The 2 groups both had higher PNN5os in the nocturnal time, and there was no significant difference (P>O. O5). Conclusion The results suggest that the total autonpmlc nerve function and vagal function of patients with FD are normal vagal activities of the 2 groups are both increased in the nocturnal period. The reason for tbe nocturnal episodes of alkalinization is not a decrease of vagal activity with a subsequent decrease of 展开更多
关键词 GASTRIC pH monitoring heart rate variability vagal function
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无创血流动力学监测在门诊左室射血分数降低心衰患者治疗中的应用价值 被引量:1
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作者 蔡文玉 杨洁 +1 位作者 张登庆 庄惠真 《中国现代药物应用》 2025年第18期54-57,共4页
目的探讨门诊左室射血分数(LVEF)降低心力衰竭(心衰)患者应用无创血流动力学监测指导治疗的价值。方法选取80例门诊LVEF降低心衰患者,按照随机数字表法分成干预组(n=40)与常规组(n=40)。常规组采取常规治疗方法,干预组根据无创血流动力... 目的探讨门诊左室射血分数(LVEF)降低心力衰竭(心衰)患者应用无创血流动力学监测指导治疗的价值。方法选取80例门诊LVEF降低心衰患者,按照随机数字表法分成干预组(n=40)与常规组(n=40)。常规组采取常规治疗方法,干预组根据无创血流动力学监测指导治疗。治疗后随访1年,对比两组治疗前、治疗后半年、治疗后1年的灌注参数[心输出量(CO)、每搏输出量(SV)、每搏外周阻力(SSVR)]、心功能指标[LVEF、舒张末期容积指数(EDI)、舒张末期容积(EDV)]及N末端B型钠尿肽前体(NT-proBNP)水平,再住院情况。结果治疗后半年与1年,两组CO、SV较本组治疗前升高,SSVR较本组治疗前降低;治疗后1年,两组CO、SV较本组治疗后半年升高,SSVR较本组治疗后半年降低;且治疗后半年与1年,干预组CO、SV均高于常规组同期,SSVR均低于常规组同期(P<0.05)。治疗后半年与1年,两组LVEF、EDI较本组治疗前升高,EDV较本组治疗前降低;治疗后1年,两组LVEF、EDI较本组治疗后半年升高,EDV较本组治疗后半年降低;且治疗后半年与1年,干预组LVEF、EDI均高于常规组同期,EDV均低于常规组同期(P<0.05)。治疗后半年与1年,两组NT-proBNP水平较本组治疗前降低;治疗后1年,两组NT-proBNP水平较本组治疗后半年降低;且治疗后半年与1年,干预组NT-proBNP(1684.45±146.65)、(1045.25±101.15)pg/ml均低于常规组同期的(2041.15±188.56)、(1521.14±141.28)pg/ml(P<0.05)。治疗后随访1年,干预组2例(5.00%)再住院,常规组9例(22.50%)再住院。干预组再住院率低于常规组(P<0.05)。结论针对门诊LVEF降低心衰患者,通过无创血流动力学监测指导治疗,可以显著改善患者灌注情况,提高心功能水平,降低患者再住院率,值得推广。 展开更多
关键词 左室射血分数降低 心力衰竭 无创血流动力学监测 心功能
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免疫抑制剂治疗期间免疫功能监测临床意义探讨 被引量:1
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作者 贾慧宇 王书旺 《河北北方学院学报(自然科学版)》 2025年第4期27-29,共3页
目的 探讨免疫抑制剂治疗期间免疫功能监测的临床意义,以提高治疗安全性和有效性。方法 选取接受免疫抑制剂治疗的98例患者按随机数字表法分为对照组和观察组各49例。对照组采用常规监测方法,观察组采用综合监测策略。观察患者免疫功能... 目的 探讨免疫抑制剂治疗期间免疫功能监测的临床意义,以提高治疗安全性和有效性。方法 选取接受免疫抑制剂治疗的98例患者按随机数字表法分为对照组和观察组各49例。对照组采用常规监测方法,观察组采用综合监测策略。观察患者免疫功能指标、感染发生率。结果 观察组患者T淋巴细胞亚群、B淋巴细胞、自然杀伤细胞、免疫球蛋白G、补体C3等免疫功能指标均明显高于对照组,差异有统计学意义(P<0.05)。观察组患者感染发生率明显低于对照组,差异有统计学意义(P<0.05)。结论 综合监测策略在免疫抑制剂治疗期间对患者免疫功能的监测具有重要意义,可有效降低感染风险,提高患者免疫力,保障患者的安全和有效治疗。 展开更多
关键词 免疫抑制剂 免疫功能监测 治疗策略
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Assessment of Non-Contact Measurement Using a Microwave Sensor to Jugular Venous Pulse Monitoring
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作者 Satoshi Suzuki Masaaki Hoshiga +1 位作者 Kentaro Kotani Takafumi Asao 《Journal of Biomedical Science and Engineering》 2021年第3期94-102,共9页
The jugular venous pulse (JVP) waveform provides an insight into right heart function, and its assessment is important in patients with heart failure. However, the conventional pulse-transducer (contact) method for mo... The jugular venous pulse (JVP) waveform provides an insight into right heart function, and its assessment is important in patients with heart failure. However, the conventional pulse-transducer (contact) method for monitoring this waveform is not frequently used because it requires a high degree of skill. The aim of this study was to confirm the effectiveness of a prototype non-contact system that employs microwave radar (24 GHz, 7 mW;non-contact system) for JVP measurement. Experiments were conducted on eight healthy male volunteers (21.88 ± 0.99 years). JVP measurements were compared between the conventional contact method and the proposed non-contact method. Change in JVP waveform was measured in response to an angle of reclining in five steps from the supine position to 75<span style="white-space:nowrap;">°</span> of elevation. The obtained JVP measurements were similar between the two methods. Because in the non-contact method the faint pulsation of the JVP is not suppressed by the pressure of a sensor placed on the skin, the prototype microwave radar system is particularly suitable for evaluating the JVP waveform. 展开更多
关键词 Microwave Radar Non-Contact monitoring Jugular Venous Pressure Right Heart function
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改进YOLOv8的矿井人员防护装备实时监测方法研究 被引量:3
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作者 张磊 孙志鹏 +3 位作者 陶虹京 郝尚凯 燕倩如 李熙尉 《煤炭科学技术》 北大核心 2025年第S1期354-365,共12页
穿戴个人防护装备是保障矿井人员作业安全的重要手段,开展矿井人员防护装备监测是煤矿安全管理的重要工作内容。煤矿井下环境较为复杂,视频监控易受到噪声、光照以及粉尘等因素干扰,导致现有的目标检测方法对矿井人员防护装备存在检测... 穿戴个人防护装备是保障矿井人员作业安全的重要手段,开展矿井人员防护装备监测是煤矿安全管理的重要工作内容。煤矿井下环境较为复杂,视频监控易受到噪声、光照以及粉尘等因素干扰,导致现有的目标检测方法对矿井人员防护装备存在检测精度低、实时性差、模型复杂度高等问题。为此,提出一种改进YOLOv8的矿井人员防护装备实时监测方法,称为DBE-YOLO。DBEYOLO模型首先在基准模型主干网络的CBS模块中结合可变形卷积(DCNv2)组成DBS模块,使卷积具有可变形能力,在采样时可以更贴近检测物体的真实形状和尺寸,更具有鲁棒性,有效提升了其对不同尺度目标的特征获取能力,有利于模型提取更多人员防护装备的特征信息,提高模型检测精度。其次在特征增强网络融合了加权双向特征金字塔机制(BiFPN),在多尺度特征融合过程中删除效率较低的特征传输节点,实现更高层次的融合,提高了对不同尺度特征的融合效率,同时BiFPN引入了一个可以学习的权值,有助于让网络学习不同输入特征的重要性。最后使用WIoUv3作为模型的损失函数,其通过动态分配梯度增益,重点关注普通锚框质量,在模型训练过程中减少了低质量锚框产生的有害梯度,进一步提升了模型性能。实验结果表明,DBE-YOLO模型在矿井人员防护装备监测中有着良好的效果,查准率、查全率、平均精度分别为93.1%、93.0%、95.8%,相较于基准模型分别提高0.8%,2.9%,2.9%,检测实时性提升到65 f·s^(-1),提高了8.3%,此外,参数量、浮点计算量、模型体积分别为2 M、6.6 G、4.4 MB,相较于原模型分别降低33.3%、18.5%、30.2%。使用煤矿现场作业视频监控对改进模型进行验证,其有效改善了漏检和误检问题,为提高矿井人员的作业安全提供了技术手段。 展开更多
关键词 可变形卷积 目标检测 损失函数 深度学习 实时监测
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结构功能一体化储能系统监测与管理综述
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作者 张献 黄飞鹏 +2 位作者 罗耀辉 徐志成 蒋凯 《电工技术学报》 北大核心 2025年第24期8136-8155,共20页
以锂离子电池为代表的新型储能系统凭借其卓越的综合性能,在新一代新能源汽车和储能产业中占据主导地位。随着对储能密度和安全性能要求的不断提升,储能系统面临电池材料性能不足、安全可靠性差以及运维管理效率低等挑战。结构功能一体... 以锂离子电池为代表的新型储能系统凭借其卓越的综合性能,在新一代新能源汽车和储能产业中占据主导地位。随着对储能密度和安全性能要求的不断提升,储能系统面临电池材料性能不足、安全可靠性差以及运维管理效率低等挑战。结构功能一体化技术因其独特优势,能够同时满足能量密度提升、高安全运行及智能化管理需求,在储能领域展现出巨大的发展和应用潜力。对此,该文将从电池材料-电池单体-储能系统三个层级全面综述结构功能一体化技术的研究和发展现状。首先,系统地回顾了结构功能一体化技术在新型电池研发领域的研究进展和主要成果;其次,深入分析结构功能一体化技术在储能系统状态监测和智能管理中的关键作用;最后,从新型材料研发、状态智能监测、系统运维管理等方面总结了结构功能一体化技术发展过程中亟待解决的关键问题,并展望了该领域的未来研究方向。 展开更多
关键词 结构功能一体化 结构电池 状态监测 智能管理
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Elimination of the impact of vessels on ocean wave height inversion with X-band wave monitoring radar
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作者 王立 吴雄斌 +2 位作者 马克涛 田云 费跃军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期1114-1121,共8页
Directional wave spectra and integrated wave parameters can be derived from X-band radar sea surface images.A vessel on the sea surface has a significant influence on wave parameter inversions that can be seen as inte... Directional wave spectra and integrated wave parameters can be derived from X-band radar sea surface images.A vessel on the sea surface has a significant influence on wave parameter inversions that can be seen as intensive backscatter speckles in X-band wave monitoring radar sea surface images.A novel algorithm to eliminate the interference of vessels in ocean wave height inversions from X-band wave monitoring radar is proposed.This algorithm is based on the characteristics of the interference.The principal components(PCs) of a sea surface image sequence are extracted using empirical orthogonal function(EOF)analysis.The standard deviation of the PCs is then used to identify vessel interference within the image sequence.To mitigate the interference,a suppression method based on a frequency domain geometric model is applied.The algorithm framework has been applied to OSMAR-X,a wave monitoring system developed by Wuhan University,based on nautical X-band radar.Several sea surface images captured on vessels by OSMAR-X are processed using the method proposed in this paper.Inversion schemes are validated by comparisons with data from in situ wave buoys.The root-mean-square error between the significant wave heights(SWH) retrieved from original interference radar images and those measured by the buoy is reduced by 0.25 m.The determinations of surface gravity wave parameters,in particular SWH,confirm the applicability of the proposed method. 展开更多
关键词 X-band wave monitoring radar vessel interference empirical orthogonal function(EOF) significant wave heights(SWH) frequency domain geometric model
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基于GNSS时序数据的西部矿区地表动态沉陷预测模型研究
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作者 汤伏全 高佳坤 +3 位作者 薛俊磊 朱超 周对对 李小涛 《煤炭科学技术》 北大核心 2025年第10期33-44,共12页
矿区GNSS连续监测站相比常规观测站能够更好地获取地表动态沉陷特征,但布设GNSS站点太多及费用过高制约了其实际应用。为了探讨基于少量站点GNSS连续观测数据构建地表动态沉陷模型的可行性,以黄土高原矿区地表沉陷监测工程为实例,通过... 矿区GNSS连续监测站相比常规观测站能够更好地获取地表动态沉陷特征,但布设GNSS站点太多及费用过高制约了其实际应用。为了探讨基于少量站点GNSS连续观测数据构建地表动态沉陷模型的可行性,以黄土高原矿区地表沉陷监测工程为实例,通过绘制地表点动态下沉及其下沉速度与加速度变化曲线,发现其分布特征与Boltzmann角度函数及其一阶、二阶导数的变化曲线高度一致,因此选择具有“S”型分布特征的Boltzmann角度函数构建地表动态下沉模型,引入相对位置角x和偏心角y两个参数描述监测站与工作面动态边界的相对位置关系,利用GNSS时序观测数据反演Boltzmann模型的4个参数(A_(1)、A_(2)、a、b),并阐明了各参数的物理意义及其变化特征。基于此,利用工作面推进过程中获取的GNSS时序观测数据构建了地表动态沉陷Boltzmann模型,通过分析模型参数随工作面推进位置(参数x)的变化特征,发现这些参数的时序变化随地表沉陷量增大而趋于稳定值,利用该模型可实现后续沉陷量的精准预测。进一步分析发现,主断面上各GNSS站点Boltzmann模型参数的空间变化符合高斯函数分布特征,采用不少于5个GNSS站点的观测数据即可稳定拟合高斯函数参数,据此建立了地表任意点动态沉陷的Boltzmann预测模型。实测数据验证表明,上述基于少数(不少于5个)站点GNSS时序观测数据所构建的Boltzmann模型,具有很好的参数确定性及预测精度,这为西部矿区地表沉陷的动态监测和预测提供了有效手段。 展开更多
关键词 西部矿区 GNSS连续监测 动态沉陷 Boltzmann角度函数 预测模型
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