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Effects of Beam Startup Characteristics on Dose Delivery Accuracy at Low Monitor Units in Step-and-Shoot Intensity Modulated Radiation Therapy 被引量:3
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作者 Kazunori Fujimoto Kunihiko Tateoka +12 位作者 Yuji Yaegashi Katsumi Shima Junji Suzuki Yuichi Saito Akihiro Nakata Takuya Nakazawa Tadanori Abe Masaki Yano Masanori Someya Kensei Nakata Masakazu Hori Masato Hareyama Koichi Sakata 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2013年第1期1-5,共5页
Intensity modulated radiation therapy (IMRT) is a highly accurate technique that is usually implemented in either dynamic or step-and-shoot fashion with many segments each having low monitor units (MUs). The present s... Intensity modulated radiation therapy (IMRT) is a highly accurate technique that is usually implemented in either dynamic or step-and-shoot fashion with many segments each having low monitor units (MUs). The present study evaluated the effects of beam startup characteristics on the dose delivery accuracy for each segment at low MUs for step-and-shoot IMRT with an Elekta Precise accelerator at the highest dose rates. We used a two-dimensional semi-conductor detector for the dose measurements. The field size of each segment was assumed to be 20 ×20 cm2 and each segment was set to deliver 1 - 10 MUs. Our results show a variation in dose delivery accuracy between segments for the same IMRT beam, which can be attributed to the beam startup characteristics. This variability is attributed to the changes in the transient changes in the temperatures of the electron gun filament and the magnetron. That is, the transient increase in the temperature of the filament leads to increasing doses with time and that of the magnetron leads to decreasing doses with time during the first few MUs. 展开更多
关键词 Startup Performance Step-and-Shoot IMRT LOW monitor unitS
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Pros and cons of continuous glucose monitoring in the intensive care unit 被引量:5
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作者 Ming-Tsung Sun I-Cheng Li +1 位作者 Wei-Shiang Lin Gen-Min Lin 《World Journal of Clinical Cases》 SCIE 2021年第29期8666-8670,共5页
Diabetes mellitus affects people worldwide,and management of its acute complications or treatment-related adverse events is particularly important in critically ill patients.Previous reports have confirmed that hyperg... Diabetes mellitus affects people worldwide,and management of its acute complications or treatment-related adverse events is particularly important in critically ill patients.Previous reports have confirmed that hyperglycemia can increase the risk of mortality in patients cared in the intensive care unit(ICU).In addition,severe and multiple hypoglycemia increases the risk of mortality when using insulin or intensive antidiabetic therapy.The innovation of continuous glucose monitoring(CGM)may help to alert medical caregivers with regard to the development of hyperglycemia and hypoglycemia,which may decrease the potential complications in patients in the ICU.The major limitation of CGM is the measurement of interstitial glucose levels rather than real-time blood glucose levels;thus,there will be a delay in the treatment of hyperglycemia and hypoglycemia in patients.Recently,the European Union approved a state-of-art artificial intelligence directed loop system coordinated by CGM and a continuous insulin pump for diabetes control,which may provide a practical way to prevent acute adverse glycemic events related to antidiabetic therapy in critically ill patients.In this mini-review paper,we describe the application of CGM to patients in the ICU and summarize the pros and cons of CGM. 展开更多
关键词 Continuous glucose monitor DIABETES INSULIN Intensive care unit HYPOGLYCEMIA
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Adaptive Signal Enhancement Unit for EEG Analysis in Remote Patient Care Monitoring Systems 被引量:1
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作者 Ch.Srinivas K.Chandrabhushana Rao 《Computers, Materials & Continua》 SCIE EI 2021年第5期1801-1817,共17页
In this paper we propose an efcient process of physiological artifact elimination methodology from brain waves(BW),which are also commonly known as electroencephalogram(EEG)signal.In a clinical environment during the ... In this paper we propose an efcient process of physiological artifact elimination methodology from brain waves(BW),which are also commonly known as electroencephalogram(EEG)signal.In a clinical environment during the acquisition of BW several artifacts contaminates the actual BW component.This leads to inaccurate and ambiguous diagnosis.As the statistical nature of the EEG signal is more non-stationery,adaptive ltering is the more promising method for the process of artifact elimination.In clinical conditions,the conventional adaptive techniques require many numbers of computational operations and leads to data samples overlapping and instability of the algorithm used.This causes delay in diagnosis and decision making.To overcome this problem in our work we propose to set a threshold value to diminish the problem of round off error.The resultant adaptive algorithm based on this strategy is Non-linear Least mean square(NL2MS)algorithm.Again,to improve this algorithm in terms of ltering capability we perform data normalization,using this algorithm several hybrid versions are developed to improve ltering and reduce computational operations.Using the method,a new signal enhancement unit(SEU)is realized and performance of various hybrid versions of algorithms examined using real EEG signals recorded from the subject.The ability of the proposed schemes is measured in terms of convergence,enhancement and multiplications required.Among various SEUs,the MCN2L 2MS algorithm achieves 14.6734,12.8732,10.9257,15.7790 dB during the artifact removal of RA,EMG,CSA and EBA components with only two multiplications.Hence,this algorithm seems to be better candidate for artifact elimination. 展开更多
关键词 Adaptive algorithms ARTIFACTS brain waves clipped algorithms signal enhancement unit wireless EEG monitoring
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考虑并网监测信息的有源配电网μPMU优化配置
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作者 梁振锋 田雨鑫 +1 位作者 闫俊杰 王晓卫 《电力系统及其自动化学报》 北大核心 2025年第3期66-74,共9页
为提高有源配电网状态估计精度,提出一种考虑并网监测信息的微型同步相量测量单元优化配置方法。分析有源配电网数据终端单元、分布式电源和电动汽车并网点监测装置、高级量测体系及微型同步相量测量单元等量测信息特征,建立以混合状态... 为提高有源配电网状态估计精度,提出一种考虑并网监测信息的微型同步相量测量单元优化配置方法。分析有源配电网数据终端单元、分布式电源和电动汽车并网点监测装置、高级量测体系及微型同步相量测量单元等量测信息特征,建立以混合状态估计平均绝对误差最小为目标函数、以微型同步相量测量单元安装数目和状态估计最大允许误差为约束条件的微型同步相量测量单元优化配置模型,并采用粒子群优化算法求解。算例分析表明,考虑并网点监测数据能有效提升状态估计精度,且可减少微型同步相量测量单元的配置数量。 展开更多
关键词 并网点监测 有源配电网 微型同步相量测量单元 优化配置 状态估计 粒子群优化算法
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PMU Based Monitoring and Estimation of Inter-area Power Oscillation for Singapore-Malaysia Interconnection Power System 被引量:2
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作者 Dikpride Despa Yasunori Mitani +1 位作者 Masayuki Watanabe Changsong Li 《Journal of Energy and Power Engineering》 2012年第3期463-468,共6页
This paper proposes a PMU (phasor measurement unit) based monitoring and estimation scheme of power system small-signal stability in Singapore-Malaysia interconnection power system through a 50-Hz and 500 kV transmi... This paper proposes a PMU (phasor measurement unit) based monitoring and estimation scheme of power system small-signal stability in Singapore-Malaysia interconnection power system through a 50-Hz and 500 kV transmission line. Two PMUs are installed in the power system interconnection network of Singapore-Malaysia. One PMU is located in Singapore and the other one in Malaysia (Penang). Both PMUs measure the single-phase voltage phasor. The data filtering technique based on FFT (Fast Fourier Transform) is employed to extract oscillation data for single mode. Finally, some analysis results of monitoring and estimation of Singapore-Malaysia interconnected power system based on application practice of the CampusWAMS are presented and analyzed. 展开更多
关键词 Phasor measurement unit wide-area monitoring power system oscillation FFT filter.
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Beam Characteristics at Low Dose Monitor Unit Settings for Vero4DRT
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作者 Hideharu Miura Shuichi Ozawa +3 位作者 Shintaro Tsuda Masahiro Hayata Kiyoshi Yamada Yasushi Nagata 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2015年第4期284-289,共6页
The stability of delivery of low monitor unit (MU) setting is important especially for step-and-shoot intensity-modulated radiotherapy (IMRT), because the nature of the technique is inherent to repeat beam on/off acco... The stability of delivery of low monitor unit (MU) setting is important especially for step-and-shoot intensity-modulated radiotherapy (IMRT), because the nature of the technique is inherent to repeat beam on/off according to the number of the segments. This study evaluates the dose linearity and profile flatness/symmetry under low MU settings for Vero4DRT, a new linear-accelerator based irradiation system that currently implements step-and-shoot IMRT. To evaluate the dose linearity and flatness/symmetry, the point doses and beam profiles were measured as functions of MU and dose rates. The accuracy of dose delivery depended on the dose rate. Under all dose rates, the dose was linear within 1% above 5 MU and within 2% above 3 MU. The beam symmetry was degraded in-line compared with crossline, although both profiles were symmetric within 2% at all dose settings. The profile flatness was also within 2% above 5 MU at any dose rate and showed no significant variation among the low MU settings. To ensure stable beam delivery without increasing the treatment time of Vero4DRT, we recommend a delivery of 5 MU per segment at a dose rate of 500 MU/min. 展开更多
关键词 Vero4DRT Step-and-Shoot IMRT Low monitor unit Beam Characteristic
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Assessment of Monitor Units and Gamma Pass Rate for 6 MV and Flattening Filter Free (FFF) Beams in Volumetric Modulated Arc Therapy (VMAT)
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作者 Kwame Anokye Amoabeng Anne Beate Langeland Marthinsen +4 位作者 Francis Hasford Samuel Nii Adu Tagoe Evelyn Anaafi Mark Pokoo-Aikins Theresa Bebaaku Dery 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2023年第1期1-8,共8页
Background: In linear accelerators, the treatment field’s uniform intensity is achieved by including a flattening filter in the beam. However, to produce more conformal dose distributions, contemporary radiotherapy p... Background: In linear accelerators, the treatment field’s uniform intensity is achieved by including a flattening filter in the beam. However, to produce more conformal dose distributions, contemporary radiotherapy practice now frequently uses fluence and aperture modifying techniques, such as volumetric modulated arc therapy. In these circumstances, the flattening filter in the beam manufacturing process is no longer required. It is therefore necessary to compare the monitor units of 6 MV and flattening filter free plans and how it influences the gamma pass rates to determine which is best for treating cervical cancer with pelvic lymph node metastasis. Methods: VMAT plans for fifteen patients with cervical cancer with pathological pelvic lymph node metastasis were included in this study. Each patient had two VMAT plans using conventional 6 MV beam with flattening filter and one with flattening filter free beam (FFF). The VMAT plans were made using two arcs, and then recalculated to give the planned dose distribution to the detectors in a Delta4 phantom. The VMAT plans were irradiated on the Delta4 phantom using an Elekta linear accelerator (6 MV). Results: The mean monitor unit for the 6 MV plans was 506.3 MU and a standard deviation of 48.6 while that of the FFF plans had a mean MU of 701.5 with a standard deviation of 87.6. The total monitor units (MUs) for the FFF plans were significantly greater than the 6 MV plans (p = 6.1 × 10<sup>-5</sup>). Conclusion: Flattening filter free (FFF) plans require more numbers of monitor units in comparison to conventional 6 MV filtered beams for external radiation of cervical cancer with pelvic lymph nodes involvement. 展开更多
关键词 monitor units Gamma Pass Rate Flattening Filter Free multileaf Collimator
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Research and Development of a Communication Monitor to a Distribution Management System
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作者 杨公训 王健康 +1 位作者 周春良 杨彦从 《Journal of China University of Mining and Technology》 2002年第1期43-47,共5页
Based on the existed equipment (the power line carrier, optic fiber, twisted pair and wireless apparatus) being used to the same route in the current communication net of distribution management system (DMS), this pap... Based on the existed equipment (the power line carrier, optic fiber, twisted pair and wireless apparatus) being used to the same route in the current communication net of distribution management system (DMS), this paper presents a new kind of communication monitor DMS, which provides a communication monitoring interface and then by DMS, data transfer problem from field terminal unit to junction center station can be solved and the communication channels can also be supervised. At the same time, synthetically using computer communication, internet technology and database technology, this system can realize the real time monitoring and fault locating in the communication network. 展开更多
关键词 communication monitor system link control unit (LCU) distribution management system(DMS) DATABASE
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Advancement in Wide Area Monitoring Protection and Control Using PMU’s Model in MATLAB/SIMULINK
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作者 Waheed Ur Rahman Muhammad Ali +7 位作者 Amjad Ullah Hafeez Ur Rahman Majid Iqbal Haseeb Ahmad Adnan Zeb Zeeshan Ali M. Ahsan Shahzad Beenish Taj 《Smart Grid and Renewable Energy》 2012年第4期294-307,共14页
A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power system... A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power systems worldwide and has led to operation of power systems closer to their stability limits and to power exchange in new patterns. These issues, as well as the on-going worldwide trend towards deregulation of the entire industry on the one hand and the increased need for accurate and better network monitoring on the other hand, force power utilities exposed to this pressure to demand new solutions for wide area monitoring, protection and control. Wide-area monitoring, protection, and control require communicating the specific-node information to a remote station but all information should be time synchronized so that to neutralize the time difference between information. It gives a complete simultaneous snap shot of the power system. The conventional system is not able to satisfy the time-synchronized requirement of power system. Phasor Measurement Unit (PMU) is enabler of time-synchronized measurement, it communicate the synchronized local information to remote station. 展开更多
关键词 WIDE Area monitorING Protection and CONTROL (WAMPAC) Phasor Measurement unit (Pmu) WIDE Area monitorING (WAM) Global Positioning System (GPS) WIDE Area CONTROLLER (WAC) Local Area CONTROLLER (LAC) Phase Angle monitorING (PAM) Automatic Generation CONTROL (AGC) Circuit Breaker (CB) Current TRANSFORMERS (CTs) Potential TRANSFORMERS (PTs)
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A HybridManufacturing ProcessMonitoringMethod Using Stacked Gated Recurrent Unit and Random Forest
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作者 Chao-Lung Yang Atinkut Atinafu Yilma +2 位作者 Bereket Haile Woldegiorgis Hendrik Tampubolon Hendri Sutrisno 《Intelligent Automation & Soft Computing》 2024年第2期233-254,共22页
This study proposed a new real-time manufacturing process monitoring method to monitor and detect process shifts in manufacturing operations.Since real-time production process monitoring is critical in today’s smart ... This study proposed a new real-time manufacturing process monitoring method to monitor and detect process shifts in manufacturing operations.Since real-time production process monitoring is critical in today’s smart manufacturing.The more robust the monitoring model,the more reliable a process is to be under control.In the past,many researchers have developed real-time monitoring methods to detect process shifts early.However,thesemethods have limitations in detecting process shifts as quickly as possible and handling various data volumes and varieties.In this paper,a robust monitoring model combining Gated Recurrent Unit(GRU)and Random Forest(RF)with Real-Time Contrast(RTC)called GRU-RF-RTC was proposed to detect process shifts rapidly.The effectiveness of the proposed GRU-RF-RTC model is first evaluated using multivariate normal and nonnormal distribution datasets.Then,to prove the applicability of the proposed model in a realmanufacturing setting,the model was evaluated using real-world normal and non-normal problems.The results demonstrate that the proposed GRU-RF-RTC outperforms other methods in detecting process shifts quickly with the lowest average out-of-control run length(ARL1)in all synthesis and real-world problems under normal and non-normal cases.The experiment results on real-world problems highlight the significance of the proposed GRU-RF-RTC model in modern manufacturing process monitoring applications.The result reveals that the proposed method improves the shift detection capability by 42.14%in normal and 43.64%in gamma distribution problems. 展开更多
关键词 Smart manufacturing process monitoring quality control gated recurrent unit neural network random forest
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Research on Network-based Integrated Condition Monitoring Unit for Rotating Machinery
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作者 XIXiao-peng ZHANGWen-rui +2 位作者 XIShuan-min JINGMin-qing YULie 《International Journal of Plant Engineering and Management》 2004年第3期139-144,共6页
In this paper, a network-based monitoring unit for condition monitoring andfault diagnosis of rotating machinery is designed and implemented. With the technology of DSP(Digital signal processing) , TCP/IP, and simulta... In this paper, a network-based monitoring unit for condition monitoring andfault diagnosis of rotating machinery is designed and implemented. With the technology of DSP(Digital signal processing) , TCP/IP, and simultaneous acquisition, a mechanism of multi-process andinter-process communication, the integrating problem of signal acquisition, the data dynamicmanagement and network-based configuration in the embedded condition monitoring system is solved. Itoffers the input function of monitoring information for network-based condition monitoring and afault diagnosis system. 展开更多
关键词 condition monitoring integrated monitoring unit network-basedconfiguration interprocess communication digital signal processing
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ZIZ-2 Vibration monitoring and diagnosing system for turbine generator units
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《Electricity》 1996年第1期53-53,共1页
ZJZ-2 system has the following functions: (1) Real-time on-line sampling and FFT analysis (32 channel); (2) Data aquisition, analysis and storage during start-up and shut-down; (3) Alarming, emergency recognition and ... ZJZ-2 system has the following functions: (1) Real-time on-line sampling and FFT analysis (32 channel); (2) Data aquisition, analysis and storage during start-up and shut-down; (3) Alarming, emergency recognition and fault retrieval; (4) Data aquisition, analysis and storage during daily operation; (5) Recall of historic data; (6) Output of routine reports and tables; (7) Analysis of vibration behaviour: Bode plot, polar plot, spectrum, cascade, waveform, shaft orbit, trend, etc; 展开更多
关键词 LINE ZIZ-2 Vibration monitoring and diagnosing system for turbine generator units
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基于量测数据自适应修正的PMU/PQMD混合谐波状态估计
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作者 詹翔 邵振国 +2 位作者 林俊杰 陈飞雄 张嫣 《电网技术》 北大核心 2025年第11期4811-4820,I0129,I0130,共12页
准确的谐波状态估计是治理电网谐波问题的重要基础。针对同步相量测量装置(phasor measurement unit,PMU)难以满足可观性条件和电能质量监测装置(power quality monitoring device,PQMD)时标非同步的问题,该文以PMU采样时刻作为估计时刻... 准确的谐波状态估计是治理电网谐波问题的重要基础。针对同步相量测量装置(phasor measurement unit,PMU)难以满足可观性条件和电能质量监测装置(power quality monitoring device,PQMD)时标非同步的问题,该文以PMU采样时刻作为估计时刻,提出一种基于量测数据自适应修正的PMU/PQMD混合谐波状态估计方法,旨在获取准确的谐波状态量。首先,在PQMD统计型数据中引入寻优因子,将PQMD测点的谐波数据表征为有界的不确定性变量,并构建PMU和PQMD的混合谐波量测集;其次,以最小标准化量测残差平方和为优化目标,建立混合谐波状态估计模型;之后,运用线性规划算法将状态估计模型简化为凸优化模型,并采用内点法进行求解,利用寻优因子在求解过程中自适应修正PQMD测点的谐波数据,以提升状态估计的精度;最后,在IEEE标准系统中验证所提方法的可行性与优越性。 展开更多
关键词 同步相量测量装置 电能质量监测装置 混合量测数据 谐波状态估计
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Sedation and analgesia strategies in the neuro intensive care unit
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作者 Zachary I Merhavy Tereque Raeburn +2 位作者 Gloria M Torres-Ayala Melissa A McCulloch Thomas C Varkey 《World Journal of Critical Care Medicine》 2025年第4期48-63,共16页
Intensivists are often plagued with the challenges of managing critically ill patients in the neurocritical intensive care unit(neuro ICU);one such challenge is the level of illness and the need for sedation,inhibitin... Intensivists are often plagued with the challenges of managing critically ill patients in the neurocritical intensive care unit(neuro ICU);one such challenge is the level of illness and the need for sedation,inhibiting the provider’s ability to adequately assess the patient.Most sedatives alter neurological and physical exam findings,only compounding potential barriers to providing the best care for each patient.It is important to emphasize that even in the altered mentation of these patients,physical and neurological exams reign supreme as diagnostic tools and should be used in conjunction with multimodal neuromonitoring methods,rather than labs or imaging alone.Additionally,selecting the appropriate analgesic(s)and sedative(s)based on these findings are highly important when determining the best course of individualized management.Thus,providers in the neuro ICU should be highly familiar with the appropriate analgesic and sedative options available in order to determine not only which may be best for each patient,but to also better understand how each drug may impact assessment findings.This comprehensive review aims to provide a structured overview of the pertinent sedatives commonly used in neuro ICUs,their risks and benefits,and how providers can best utilize each in practice to further improve patient outcomes.The novel contribution of this work provides comparative drug tables,dosing guidance for pediatric and very elderly(>85-years-old)populations,and an exploration into the future possibilities of utilizing artificial intelligence and the human gut microbiome to further enhance the prospects of precision medicine. 展开更多
关键词 ANESTHESIA DEXMEDETOMIDINE Critical care Hemodynamic monitoring Intensive care unit outcomes Intensive care Medical intensive care unit multidisciplinary critical care Neurocritical care Neuro intensive care unit
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Correlations of vancomycin trough concentration and its efficacy and toxicity in patients in the intensive care unit
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作者 Teng Guo Li-Ying Du +2 位作者 Ming-Feng Liu Xia-Jin Zhou Xin-Ran Chen 《World Journal of Clinical Cases》 2025年第16期18-28,共11页
BACKGROUND Plasma concentration monitoring is crucial for optimizing vancomycin use,particularly in patients in the intensive care unit(ICU).However,the reference interval for vancomycin plasma concentration remains u... BACKGROUND Plasma concentration monitoring is crucial for optimizing vancomycin use,particularly in patients in the intensive care unit(ICU).However,the reference interval for vancomycin plasma concentration remains undetermined.AIM To evaluate the correlations of area under the curve(AUC_(0-24))and trough concentration(C_(min))with efficacy and nephrotoxicity in patients in the ICU.METHODS A total of 103 patients treated with vancomycin for methicillin-resistant Staphylococcus aureus infections were analyzed in this study.The associations of clinicodemographic characteristics(including sex,age,weight,infection sites,main etiologies of ICU cases,comorbidities,acute physiological chronic health evaluation II score,and mechanical ventilation)and pharmacokinetics(daily dose,C_(min),AUC_(0-24),and AUC_(0-24)/minimum inhibitory concentration)with efficacy and nephrotoxicity of vancomycin were evaluated with univariate and multivariate logistic regression analyses.AUC_(0-24)was calculated using VCM-TDM software based on vancomycin population pharmacokinetics and Bayesian feedback method.RESULTS Cmin over 9.4μg/mL and AUC_(0-24)exceeding 359.6μg×hour/mL indicated good efficacy against infection.Cmin below 14.0μg/mL predicted no significant nephrotoxicity.CONCLUSION In this study,the effective and safe concentration interval for vancomycin in patients in the ICU was Cmin 9.4-14.0μg/mL.Close attention should be paid to adverse effects and renal function during vancomycin treatment. 展开更多
关键词 VANCOMYCIN Therapeutic drug monitoring Intensive care unit Trough concentration Methicillin-resistant Staphylococcus aureus infection Area under the curve
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A tool wear monitoring method based on improved DenseNet and GRU
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作者 WANG Yue MA Yajie +1 位作者 ZHOU Jiangnan WU Yanxia 《Journal of Systems Engineering and Electronics》 2025年第6期1562-1578,共17页
The precision and quality of machining in computer numerical control(CNC)machines are significantly impacted by the state of the tool.Therefore,it is essential and crucial to monitor the tool’s condition in real time... The precision and quality of machining in computer numerical control(CNC)machines are significantly impacted by the state of the tool.Therefore,it is essential and crucial to monitor the tool’s condition in real time during operation.To improve the monitoring accuracy of tool wear values,a tool wear monitoring approach is developed in this work,which is based on an improved integrated model of densely connected convolutional network(DenseNet)and gated recurrent unit(GRU),which incorporates data preprocessing via wavelet packet transform(WPT).Firstly,wavelet packet decomposition(WPD)is used to extract time-frequency domain features from the original timeseries monitoring signals of the tool.Secondly,the multidimensional deep features are extracted from DenseNet containing asymmetric convolution kernels,and feature fusion is performed.A dilation scheme is employed to acquire more historical data by utilizing dilated convolutional kernels with different dilation rates.Finally,the GRU is utilized to extract temporal features from the extracted deep-level signal features,and the feature mapping of these temporal features is then carried out by a fully connected neural network,which ultimately achieves the monitoring of tool wear values.Comprehensive experiments conducted on reference datasets show that the proposed model performs better in terms of accuracy and generalization than other cutting-edge tool wear monitoring algorithms. 展开更多
关键词 tool wear monitoring densely connected convolutional network(DenseNet) asymmetric convolutional kernel dilated convolutional kernel gated recurrent unit(GRU)
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重症患者抗癫痫药物治疗药物监测分析
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作者 郭美华 闫振宇 +1 位作者 郭畅 海鑫 《中国医院药学杂志》 北大核心 2026年第1期52-57,共6页
目的:分析重症患者抗癫痫药物(antiepileptic drugs,AEDs)用药情况、治疗药物监测(therapeutic drug monitoring,TDM)结果的影响因素,为重症患者AEDs临床合理用药提供参考。方法:系统回顾分析哈尔滨医科大学附属第一医院2019-2024年入... 目的:分析重症患者抗癫痫药物(antiepileptic drugs,AEDs)用药情况、治疗药物监测(therapeutic drug monitoring,TDM)结果的影响因素,为重症患者AEDs临床合理用药提供参考。方法:系统回顾分析哈尔滨医科大学附属第一医院2019-2024年入住重症监护病房(intensive care unit,ICU)应用AEDs的559例患者的治疗信息,统计分析AEDs使用情况、TDM结果及影响因素。结果:ICU患者最常用的AED为丙戊酸钠(97.67%),其次为左乙拉西坦(20.57%);多数为单独用药(74.24%),且单用丙戊酸钠的比例最高(72.27%);最常用的联合方案为丙戊酸钠+左乙拉西坦;首次TDM达窗率较低(49.53%),剂量调整后达窗率显著提高至64.34%(P<0.05);给药方式、性别均可影响丙戊酸血药浓度(C)和血药浓度/剂量(C/D)(P<0.05),静脉给药,尤其是静脉持续给药后的C及C/D均高于非静脉给药(P<0.05)。结论:需强化ICU患者AEDs的TDM,重点关注给药方式及性别等因素对血药浓度的影响,依据TDM结果实施个体化用药,以提升治疗效果,降低不良反应。 展开更多
关键词 危重症患者 抗癫痫药物 治疗药物监测 影响因素
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食管癌IMRT计划设计降低子野数及MU数方法研究 被引量:10
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作者 曹彦坤 迟子锋 +3 位作者 焦广青 刘丹 李润霄 韩春 《中国医学物理学杂志》 CSCD 2011年第2期2460-2463,2470,共5页
目的:研究降低食管癌调强计划子野数及MU数的可行性方法。方法:(1)射野方向:IMRT计划由物理师按照经验非均匀共面布野。(2)优化强度级数:分别设计为12、10、8、6优化强度级数。(3)围绕PTV连续定义六个和PTV同心的空心环并限制每个环剂... 目的:研究降低食管癌调强计划子野数及MU数的可行性方法。方法:(1)射野方向:IMRT计划由物理师按照经验非均匀共面布野。(2)优化强度级数:分别设计为12、10、8、6优化强度级数。(3)围绕PTV连续定义六个和PTV同心的空心环并限制每个环剂量的计划(4)直接子野优化方法:使用DMPO模式设计,该模式允许预先设定最多子野数。结果:(1)选择的共面非均匀布野与均匀布野调强计划相比,肿瘤靶区的适形度、均匀性较好,总子野数和MU数无差异。(2)优化强度级数为12、10和8的计划质量基本相当,都满足食管癌临床要求,但优化强度级数为8的计划总子野数减少17%,MU数基本不变。(3)设定同心环并限制每个环剂量的计划,肿瘤受照剂量的适形度和正常组织受量均明显好于没有设定椭圆环的调强计划,同时该计划总子野数减少23%、总MU数减少9%。(4)与两步法调强计划相比,DMPO模式PTV的适形度更好,总子野数比原计划减少37%,总MU数减少16%。结论:通过优化强度级数选择、定义治疗靶区同心空心环、直接子野优化等方法,在不改变甚至提高原计划质量的前提下,可以减少食管癌IMRT计划总子野数和MU数。 展开更多
关键词 食管癌 调强放射治疗 子野数 跳数
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Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗计划中的应用研究 被引量:1
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作者 陈宗友 曾华驱 +5 位作者 汤树奎 林启富 梁柱 赖春任 赵善辉 温尊北 《中国医学装备》 2023年第10期53-60,共8页
目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective... 目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective工具的情况下给每例患者设计治疗参考计划(MU_(ref));将使用MU Objective工具对MU_(ref)进行重新优化,分别设置MU_(ref)的MU的30%、50%、70%、90%和120%,分别命名为MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)。将治疗计划MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)分别与MU_(ref)进行配对t检验统计分析,比较两种治疗计划的靶区、危及器官(OAR)剂量分布和计划的MU。结果:使用MU Objective工具对参考计划优化MU后,与参考计划相比部分靶区和OAR剂量体积参数差异虽有统计学意义,但无临床意义。治疗计划参数为MU_(30%)、MU_(50%)、MU_(70%)和MU_(90%)时,与MU_(ref)比较计划MU平均分别减少21.5%、19.5%、16.6%和8%,差异有统计学意义(t=9.652,t=8.843,t=8.963,t=11.323;P<0.05)。在MU_(120%)时,治疗计划MU平均增加1.7%,但未显著提高靶区剂量覆盖。结论:对于鼻咽癌VMAT计划,使用Eclipse计划系统的MU Objective工具在减少计划MU的同时可获得与参考计划相似的剂量分布。MU Objective工具可作为鼻咽癌或其他部位VMAT计划的常规使用工具,以保证计划质量同时减少放射治疗计划的MU。 展开更多
关键词 容积调强放射治疗(VMAT) Eclispe计划系统 mu Objective工具 机器跳数(mu)
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基于PMU和改进戴维南等值模型的电压稳定在线监视 被引量:51
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作者 刘明松 张伯明 +2 位作者 姚良忠 孙宏斌 吴文传 《电力系统自动化》 EI CSCD 北大核心 2009年第10期6-10,共5页
相量测量单元(PMU)量测和戴维南等值模型的结合,为电压稳定在线监视提供了新思路。文中利用电路原理的相关理论,对传统戴维南等值模型的不足进行了定性分析,并在此基础上提出了一种改进的戴维南等值模型。对改进模型的量测方程、可解性... 相量测量单元(PMU)量测和戴维南等值模型的结合,为电压稳定在线监视提供了新思路。文中利用电路原理的相关理论,对传统戴维南等值模型的不足进行了定性分析,并在此基础上提出了一种改进的戴维南等值模型。对改进模型的量测方程、可解性条件、求解方法和误差分析等方面进行了研究,以负荷裕度为电压稳定性指标,将改进模型用于电压稳定在线监视,并对数据窗的选取、改进模型的退化、应用环境等相关问题进行了分析。对IEEE 39节点系统进行了仿真,仿真结果表明改进模型比传统模型具有更好的精度和适用性。 展开更多
关键词 相量测量单元 电压稳定 在线监视 改进戴维南等值
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