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Locating the position of objects in non-line-of-sight based on time delay estimation
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作者 王雪峰 王元庆 +1 位作者 苏金善 杨兴雨 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期163-169,共7页
Non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface(diffuser).It has very important significance in indirect access to an object or dangerous object detection, ... Non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface(diffuser).It has very important significance in indirect access to an object or dangerous object detection, such as medical treatment and rescue. An approach to locating the positions of hidden objects is proposed based on time delay estimation. The time delays between the received signals and the source signal can be obtained by correlation analysis, and then the positions of hidden objects will be located. Compared with earlier systems and methods, the proposed approach has some modifications and provides significant improvements, such as quick data acquisition, simple system structure and low cost, and can locate the positions of hidden objects as well: this technology lays a good foundation for developing a practical system that can be used in real applications. 展开更多
关键词 Non-line-OF-SIGHT time delay estimation CROSS-CORRELATION hidden object location
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Passive location estimation using scatterer information for non-line-of-sight environments 被引量:1
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作者 颜俊 王林汝 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期518-522,共5页
In order to improve the performance of the traditional hybrid time-of-arrival(TOA)/angle-of-arrival(AOA)location algorithm in non-line-of-sight(NLOS)environments,a new hybrid TOA/AOA location estimation algorith... In order to improve the performance of the traditional hybrid time-of-arrival(TOA)/angle-of-arrival(AOA)location algorithm in non-line-of-sight(NLOS)environments,a new hybrid TOA/AOA location estimation algorithm by utilizing scatterer information is proposed.The linearized region of the mobile station(MS)is obtained according to the base station(BS)coordinates and the TOA measurements.The candidate points(CPs)of the MS are generated from this region.Then,using the measured TOA and AOA measurements,the radius of each scatterer is computed.Compared with the prior scatterer information,true CPs are obtained among all the CPs.The adaptive fuzzy clustering(AFC)technology is adopted to estimate the position of the MS with true CPs.Finally,simulations are conducted to evaluate the performance of the algorithm.The results demonstrate that the proposed location algorithm can significantly mitigate the NLOS effect and efficiently estimate the MS position. 展开更多
关键词 passive location time-of-arrival/angle-of-arrival(TOA/AOA) non-line-of-sight(NLOS)mitigation adaptive fuzzy clustering
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STRONGLY CONVERGENT INERTIAL FORWARD-BACKWARD-FORWARD ALGORITHM WITHOUT ON-LINE RULE FOR VARIATIONAL INEQUALITIES
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作者 姚永红 Abubakar ADAMU Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期551-566,共16页
This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inerti... This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inertial parameters and the iterates,which have been assumed by several authors whenever a strongly convergent algorithm with an inertial extrapolation step is proposed for a variational inequality problem.Consequently,our proof arguments are different from what is obtainable in the relevant literature.Finally,we give numerical tests to confirm the theoretical analysis and show that our proposed algorithm is superior to related ones in the literature. 展开更多
关键词 forward-backward-forward algorithm inertial extrapolation variational inequality on-line rule
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An envelope-based machine learning workflow for locating earthquakes in the southern Sichuan Basin
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作者 Kang Wang Jie Zhang +2 位作者 Ji Zhang Zhangyu Wang Ziyu Li 《Earthquake Research Advances》 CSCD 2024年第2期45-54,共10页
The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces ... The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces challenges in regions with limited available training data. To address the issues of sparse event distribution and inaccurate ground truth in historical seismic datasets, we expand the training dataset by using a large number of synthetic envelopes that closely resemble real data and build an earthquake location model named ENVloc. We propose an envelope-based machine learning workflow for simultaneously determining earthquake location and origin time. The method eliminates the need for phase picking and avoids the accumulation of location errors resulting from inaccurate picking results. In practical application, ENVloc is applied to several data intercepted at different starting points. We take the starting point of the time window corresponding to the highest prediction probability value as the origin time and save the predicted result as the earthquake location. We apply ENVloc to observed data acquired in the southern Sichuan Basin, China, between September 2018 and March 2019. The results show that the average difference with the catalog in latitude, longitude, depth, and origin time is 0.02°,0.02°, 2 km, and 1.25 s, respectively. These suggest that our envelope-based method provides an efficient and robust way to locate earthquakes without phase picking, and can be used in earthquake monitoring in near-real time. 展开更多
关键词 Waveform envelope Earthquake location Local seismicity Synthetic data Sparse stations
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A Multi-Objective Optimization for Locating Maintenance Stations and Operator Dispatching of Corrective Maintenance
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作者 Chao-Lung Yang Melkamu Mengistnew Teshome +1 位作者 Yu-Zhen Yeh Tamrat Yifter Meles 《Computers, Materials & Continua》 SCIE EI 2024年第6期3519-3547,共29页
In this study,we introduce a novel multi-objective optimization model tailored for modern manufacturing,aiming to mitigate the cost impacts of operational disruptions through optimized corrective maintenance.Central t... In this study,we introduce a novel multi-objective optimization model tailored for modern manufacturing,aiming to mitigate the cost impacts of operational disruptions through optimized corrective maintenance.Central to our approach is the strategic placement of maintenance stations and the efficient allocation of personnel,addressing a crucial gap in the integration of maintenance personnel dispatching and station selection.Our model uniquely combines the spatial distribution of machinery with the expertise of operators to achieve a harmonious balance between maintenance efficiency and cost-effectiveness.The core of our methodology is the NSGA Ⅲ+Dispatch,an advanced adaptation of the Non-Dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ),meticulously designed for the selection of maintenance stations and effective operator dispatching.This method integrates a comprehensive coding process,crossover operator,and mutation operator to efficiently manage multiple objectives.Rigorous empirical testing,including a detailed analysis from a taiwan region electronic equipment manufacturer,validated the effectiveness of our approach across various scenarios of machine failure frequencies and operator configurations.The findings reveal that the proposed model significantly outperforms current practices by reducing response times by up to 23%in low-frequency and 28.23%in high-frequency machine failure scenarios,leading to notable improvements in efficiency and cost reduction.Additionally,it demonstrates significant improvements in oper-ational efficiency,particularly in selective high-frequency failure contexts,while ensuring substantial manpower cost savings without compromising on operational effectiveness.This research significantly advances maintenance strategies in production environments,providing the manufacturing industry with practical,optimized solutions for diverse machine malfunction situations.Furthermore,the methodologies and principles developed in this study have potential applications in various other sectors,including healthcare,transportation,and energy,where maintenance efficiency and resource optimization are equally critical. 展开更多
关键词 Corrective maintenance multi-objective optimization non-dominated sorting genetic algorithmⅢ operator allocation maintenance station location
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On-Line Detection of EDM Spark Locations Using Potential Difference Method
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作者 栗岩 狄士春 +1 位作者 冯晓光 赵万生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第3期82-85,共4页
The valuation relation of potential difference with discharging time in Electrical Discharge Machining (EDM) is analyzed theoretically and tested and verified by experiments designed in this paper and the relation bet... The valuation relation of potential difference with discharging time in Electrical Discharge Machining (EDM) is analyzed theoretically and tested and verified by experiments designed in this paper and the relation between potential difference and spark location is induced and analyzed, and proceed by experiments under the condition of onedimension. 展开更多
关键词 SPARK locatIONS POTENTIAL DIFFERENCE method on-line detection DISCHARGING time
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Multi-Sensor Intelligent System for On-Line and Real-Time Moneitoring Tool Cutting State in FMS 被引量:1
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作者 徐春广 王信义 +1 位作者 邢济收 杨大勇 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期258-266,共9页
The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sens... The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sensor (AE) with motor current sensor was presented. The parallel communication between control system of machine tools, the monitoring intelligent system,and several decision-making systems for identifying tool cutting state was established It can auto - matically select the sensor way ,monitoring mode and identifying method in machining process- ing so as to build a successful and effective intelligent system for on -line and real-time moni- toring cutting tool states in FMS. 展开更多
关键词 tool cutting state on-line monitoring intelligent system acoustic emission sensor
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On-line机行血液透析滤过两种稀释模式效果的临床观察 被引量:2
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作者 易铁钢 祁爱蓉 程淑碧 《中国血液净化》 2004年第1期41-42,47,共3页
关键词 on-line 血液透析滤过 稀释模式 HDF 治疗 血液净化
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On-line hemodiafiltration技术和临床应用 被引量:25
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作者 谢红浪 季大玺 《肾脏病与透析肾移植杂志》 CAS CSCD 2005年第4期377-381,共5页
关键词 血液净化 肾脏疾病 临床 on-line 临床应用 肾脏替代治疗 终末期肾脏疾病 血液透析滤过 常规血液透析 生物相容性
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On-line血液透析滤过对移植肾功能延迟恢复的影响 被引量:1
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作者 余权星 刘强 +2 位作者 杜艺 李宓 彭莉 《中国血液净化》 2004年第4期192-193,200,共3页
目的 研究On -line血液透析滤过 (HDF)在移植肾功能延迟恢复患者中的应用。方法 我院2 0 0 2年 1月至 2 0 0 3年 7月肾移植术后发生移植肾功能延迟恢复患者 38例 ,2 9例采用Freseniuson -lineHDF透析机 ,F6 0透析器 ,透析滤过时间 3~... 目的 研究On -line血液透析滤过 (HDF)在移植肾功能延迟恢复患者中的应用。方法 我院2 0 0 2年 1月至 2 0 0 3年 7月肾移植术后发生移植肾功能延迟恢复患者 38例 ,2 9例采用Freseniuson -lineHDF透析机 ,F6 0透析器 ,透析滤过时间 3~ 4h ,血流量在 180~ 2 5 0ml/min ,置换液采取前稀释法 ,9例行HD治疗 ,采用GambroAK2 0 0透析机 ,F7透析器。结果  38例移植肾功能延迟恢复患者 ,2 9例用联机血液透析滤过 ,平均肾功能恢复时间为 ( 11.2± 5 .6 )天 ,治疗期间收缩压变化在 110~ 170mmHg,透析期间低血压发生率为 2 .6 % ,9例HD治疗者平均肾功能恢复时间为 ( 2 2 .3± 15 .7)天 ,透析期间低血压发生率为 13.2 %。结论 与HD比较 ,On -lineHDF对血压影响较小 ,可缩短移植肾功能恢复的时间。 展开更多
关键词 on-line血液透析 肾功能 肾移植 HDF
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Development and Application of On-Line Corrosion Monitoring Device for Condenser Tube 被引量:1
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作者 曹杰玉 宋敬霞 +2 位作者 汪德良 龙国军 孙本达 《Electricity》 2004年第2期31-35,共5页
This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current te... This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current test, which enable the monitoring result to be consistent with the corrosion of actual condenser tubes. Localized corrosion rate of condenser tubes can be measured indirectly by a galvanic couple made up of tube segments with and without pits. Using this technology, corrosion problems can be found in time and accurately, and anticorrosive measures be made more economic and effective. Applications in two power plants showed the corrosion measurements are fast and accurate. 展开更多
关键词 condenser tube CORROSION on-line monitoring INSTRUMENTATION
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平行机的实时到达on-line算法下界的改进 被引量:1
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作者 陈仕平 姚恩瑜 《高校应用数学学报(A辑)》 CSCD 北大核心 1999年第3期315-318,共4页
本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明... 本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明了该在线问题不存在性能比小于1.3473的on-line算法.本文将此界改进为(5-5)/2. 展开更多
关键词 排序 on-line算法 平行机 组合最优化 实时到达
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Effects of on-line solution and off-line heat treatment on microstructure and hardness of die-cast AZ91D alloy 被引量:1
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作者 徐玉磊 张奎 +3 位作者 李兴刚 雷健 袁海波 刘正 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2652-2658,共7页
The effects of on-line solution, off-line solution and aging heat treatment on the microstructure and hardness of the die-cast AZ91D alloys were investigated. Brinell hardness of die-cast AZ91D alloy increases through... The effects of on-line solution, off-line solution and aging heat treatment on the microstructure and hardness of the die-cast AZ91D alloys were investigated. Brinell hardness of die-cast AZ91D alloy increases through on-line solution and off-line aging treatment but decreases after off-line solution treatment. By X-ray diffractometry, optical microscopy, differential thermal analysis, scanning electron microscopy and X-ray energy dispersive spectroscopy, it is found that the microstructures of the die-cast AZ91D magnesium alloy before and after on-line solution and off-line aging are similar, consisting of α-Mg and β-Al12Mg17. The precipitation of Al element is prevented by on-line solution so that the effect of solid solution strengthening is enhanced. The β-Al12Mg17 phases precipitate from supersaturated Mg solid solution after off-line aging treatment, and lead to microstructure refinement of AZ91D alloy, so the effect of precipitation hardening is enhanced. The β-Al12Mg17 phases dissolve in the substructure after off-line solution treatment, which leads to that the grain boundary strengthening phase is reduced significantly and the hardness of die cast AZ91D is reduced. 展开更多
关键词 die-cast magnesium alloy AZ91D alloy on-line solution off-line solution treatment aging treatment β-Al12Mg17 phases microstructure refinement precipitation hardening
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An intersection method for locating earthquakes in complex velocity models 被引量:1
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作者 赵爱华 丁志峰 《Applied Geophysics》 SCIE CSCD 2007年第4期294-300,共7页
The intersection method is one of the basic approaches for locating earthquakes and is not only robust but also efficient. However, its location accuracy is not high, especially for focal depth because the velocity mo... The intersection method is one of the basic approaches for locating earthquakes and is not only robust but also efficient. However, its location accuracy is not high, especially for focal depth because the velocity model used for the conventional intersection method is based on homogeneous or laterally homogeneous media, which is too simple. In order to improve the accuracy, we have modified the existing intersection method. In the modified approach, the earthquake loci are not assumed to be circular or hyperbolic and calculation accuracy is improved using a minimum traveltime tree algorithm for tracing rays. The numerical model shows that the modified method can locate earthquakes in complex velocity models. 展开更多
关键词 Earthquake location intersection method ray tracing minimum traveltime tree algorithm
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On-line血液透析滤过对维持性血液透析患者心率变异性的影响 被引量:5
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作者 侯丹丹 王淑领 尚赛男 《临床和实验医学杂志》 2017年第17期1761-1764,共4页
目的探讨On-line血液透析滤过技术对维持性血液透析患者心率变异性(HRV)的影响。方法 50例维持性血液透析(MHD)患者随机分为常规血液透析治疗组(HD组)和On-line血液透析滤过治疗组(OL-HDF组),每组各25例。患者每周行3次、每次4 h的血液... 目的探讨On-line血液透析滤过技术对维持性血液透析患者心率变异性(HRV)的影响。方法 50例维持性血液透析(MHD)患者随机分为常规血液透析治疗组(HD组)和On-line血液透析滤过治疗组(OL-HDF组),每组各25例。患者每周行3次、每次4 h的血液透析治疗或OL-HDF,治疗24个月。比较两组常规的实验室检查和24h动态心电图监测结果。结果治疗24个月后,OL-HDF组的β2-微球蛋白(β2-MG)由基线值30.1±7.2 mg/dl降至21.7±6.1 mg/dl(P<0.05),HD组的β2-MG则无明显下降。OL-HDF组HRV的时域性和频域性指标均值高于基线值(P<0.05),HD组的HRV指标则无显著性变化(P>0.05)。结论与普通血液透析比较,OL-HDF能更好地改善MHD患者的HRV,改善自主神经功能。 展开更多
关键词 维持性血液透析 on-line血液透析滤过心率变异性
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On-line置换液与生理盐水在血液透析滤过回血中的应用效果比较 被引量:5
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作者 祝喜鹰 刘金凤 肖静 《护理研究(上旬版)》 2014年第7期2370-2372,共3页
[目的]探讨On-line置换液与生理盐水在血液透析滤过(HDF)病人回血中的应用效果,以期为临床护理工作提供理论依据。[方法]选取30例规律HDF病人为研究对象,采用自身对照方法,每例病人每周依次采用On-line置换液和生理盐水回血,比较回血过... [目的]探讨On-line置换液与生理盐水在血液透析滤过(HDF)病人回血中的应用效果,以期为临床护理工作提供理论依据。[方法]选取30例规律HDF病人为研究对象,采用自身对照方法,每例病人每周依次采用On-line置换液和生理盐水回血,比较回血过程中残余血量、静脉壶液体温度、护士的工作量及经济效益。[结果]采用On-line置换液回血法残余血量及回血后静脉壶温度分别为(1.89±0.91)mL,(33.36±0.15)℃,而采用生理盐水法为(2.88±0.23)mL、(27.13±0.14)℃,差异均有统计学意义(P<0.01);而透析器凝血状况比较差异无统计学意义(P=0.08);采用On-line置换液回血时护士工作量减少,回血液体成本降低。[结论]应用接近生理温度的On-line置换液回血能稀释血液、降低血液黏稠度,减少血路管残余血量,增加病人舒适感,提高工作效率。 展开更多
关键词 联机血液透析滤过 液体回血 on-line置换液 生理盐水 残余血量 工作量
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On-lineHDF的临床观察及护理 被引量:1
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作者 李虹 张永勤 汪吉平 《实用全科医学》 2004年第3期280-281,共2页
目的 探讨应用On -lineHDF治疗慢性肾衰尿毒症患者的临床效果及护理对策。方法 回顾性分析 15例维持性HD患者应用On -lineHDF的治疗及护理过程。结果  15例患者经每 1~ 2周 1次的On -lineHDF治疗后 ,病情稳定 ,部分患者心功能、血... 目的 探讨应用On -lineHDF治疗慢性肾衰尿毒症患者的临床效果及护理对策。方法 回顾性分析 15例维持性HD患者应用On -lineHDF的治疗及护理过程。结果  15例患者经每 1~ 2周 1次的On -lineHDF治疗后 ,病情稳定 ,部分患者心功能、血压、食欲、体力及睡眠不同成度得到改善 ,在促红细胞生成素使用量不变的情况下 ,4例病人的血红蛋白有所增加。结论 On -lineHDF是当今最佳的肾脏替代疗法技术之一。 展开更多
关键词 on-line HDF 护理措施 血液透析 置换液 治疗
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On-Line Monitoring of Cutting Tool Fracture & Wear
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作者 王信义 肖定国 宋新民 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期139-150,共12页
A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is reported.The te... A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is reported.The technique can detect breakage of drills having diameter over 0.8mm,turning cutter crack of area over 0.2mm,and the ultimate wear.The principle,system construction,experimental method and result of the technique are discussed.The ratio of success in detection approaches 96% or higher. 展开更多
关键词 on-line monitoring acoustic emission/tool fracture motor current
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On-line HDF治疗维持性透析患者并发症的护理
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作者 孙静 安茂竹 +2 位作者 毛继芳 秦美华 马芳 《当代护士(中旬刊)》 2007年第10期32-33,共2页
对20例维持性透析并发难治性高血压、顽固性瘙痒、不安腿综合征等患者,采用每周2次血液透析+1次on-line HDF,加强观察和护理。患者血压得到良好的控制,皮肤瘙痒得到明显改善,不安腿症状有所好转,贫血、食欲减退、精神和神经症状得到改善... 对20例维持性透析并发难治性高血压、顽固性瘙痒、不安腿综合征等患者,采用每周2次血液透析+1次on-line HDF,加强观察和护理。患者血压得到良好的控制,皮肤瘙痒得到明显改善,不安腿症状有所好转,贫血、食欲减退、精神和神经症状得到改善,生活质量明显提高。 展开更多
关键词 透析 并发症 on-line HDF 护理
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WORKPIECE LOCATING AND POST PROCESSING SYSTEMS ON 6-DOF CNC MILLING MACHINE
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作者 王瑞 钟诗胜 王知行 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期138-143,共6页
A conventional non-computerized numerical control (CNC) machine is updated by mounting a six degree-of-free (DOF) parallel mechanism on it, thus obtaining a new CNC one. The structure of this CNC milling machine i... A conventional non-computerized numerical control (CNC) machine is updated by mounting a six degree-of-free (DOF) parallel mechanism on it, thus obtaining a new CNC one. The structure of this CNC milling machine is introduced, and the workpiece locating system and the post processing system of the cutter location (CL) data file are analyzed. The new machine has advantages of low costs, simple structure, good rigidity, and high precision. It is easy to be transformed and used to process the workpiece with a complex surface. 展开更多
关键词 parallel kinematic machine CNC milling machine workpiece locating system post processing system
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