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Use of a Public Fishing Area Determined by Vehicle Counters with Verification by Trail Cameras
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作者 Greg Simpson 《Natural Resources》 2018年第5期188-197,共10页
This study was performed in order to determine visitation at remote areas that would be unaffordable due to logistic reasons. Four TrafxTM vehicle counters, each programmed with different settings, were placed along t... This study was performed in order to determine visitation at remote areas that would be unaffordable due to logistic reasons. Four TrafxTM vehicle counters, each programmed with different settings, were placed along the lone access road to remotely sense the daily use activities and count accuracy at the New Underwood Lake Public Water Access Area. Use was corroborated during daylight hours with game cameras. Data was stratified between weekdays/weekends due to differences between the two periods. Two counter settings, threshold and delay, were best when set at a value of 8, but a value of 16 for delay provided almost equal results. Overall, there were 38 counts of use per day for a total of 2318 over the 61 day period. This study demonstrated how vehicle counters, in combination with game cameras for verification, can aid managers for determining use in remote access areas. Future work may lead to identifying details for producing a surrogate to traditional angler use surveys. 展开更多
关键词 PUBLIC Areas VISITATION Use Survey Trafx counters TRAIL CAMERA
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Accuracy of the automated cell counters for management of spontaneous bacterial peritonitis 被引量:7
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作者 Oliviero Riggio Stefania Angeloni +4 位作者 Antonella Parente Cinzia Leboffe Giorgio Pinto Teresa Aronne Manuela Merli 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第37期5689-5694,共6页
AIM: To evaluate the accuracy of automated blood cell counters for ascitic polymorphonuclear (PMN) determination for: (1) diagnosis, (2) efficacy of the ongoing antibiotic therapy, and (3) resolution of spon... AIM: To evaluate the accuracy of automated blood cell counters for ascitic polymorphonuclear (PMN) determination for: (1) diagnosis, (2) efficacy of the ongoing antibiotic therapy, and (3) resolution of spontaneous bacterial peritonitis (SBP). METHODS: One hundred and twelve ascitic fluid samples were collected from 52 consecutive cirrhotic patients, 16 of them with SBP. The agreement between the manual and the automated method for PMN count was assessed. The sensitivity/specificity and the positive/negative predictive value of the automated blood cell counter were also calculated by considering the manual method as the "gold standard" RESULTS: The mean + SD of the difference between manual and automated measurements was 7.8 4- 58 cells/ram3, while the limits of agreement were +124 cells/mm3 [95% confidence interval (CI): +145 to +103] and -108 cells/mm3 (95% CI: -87 to -129). The automated cell counter had a sensitivity of 100% and a specificity of 97.7% in diagnosing SBP, and a sensitivity of 91% and a specificity of 100% for the efficacy of the ongoing antibiotic therapy. The two methods showed a complete agreement for the resolution of infection. CONCLUSION: Automated cell counters not only have a good diagnostic accuracy, but are also very effectivein monitoring the antibiotic treatment in patients with SBP. Because of their quicker performance, they should replace the manual counting for PMN determination in the ascitic fluid of patients with SBP. 展开更多
关键词 Spontaneous bacterial peritonitis ASCITES Polymorphonuclear cell count Automated cell counter PARACENTESIS CIRRHOSIS
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Experimental investigation on the radiation background inside body counters 被引量:3
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作者 Yu Wang Yuan-Yuan Liu +8 位作者 Bin Wu Xiang-Peng Meng Jian-Ping Cheng Ying Wang Li-Jiao Wang Yun-Shi Xiao Qin-Jian Cao Jian-Feng Zhang Fei Tuo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第2期66-78,共13页
In vivo measurement of radioactivity based on various body counters is arguably the leading measure used to determine the distribution and activity of radionuclides in human subjects,such as I-131 in the thyroid,Am-24... In vivo measurement of radioactivity based on various body counters is arguably the leading measure used to determine the distribution and activity of radionuclides in human subjects,such as I-131 in the thyroid,Am-241 in the lungs,and Pb-210 in the skull.Throughout the measurements,the radiation background is the key factor that determines the sensitivity of the counter.Therefore,to facilitate in vivo measurements,a well-designed shielding room is required to create a low-background environment.However,because the compositions of the radiation background are quite complicated,the respective contributions from each source remain obscure,which places a considerable burden on seeking an optimized design of shielding rooms that strikes the optimum balance between the construction cost and background suppression effect.In this study,we conducted a systematic experimental investigation on the radiation background outside and inside four representative body counters with assorted designs using a variety of radiation detectors,including high-purity germanium detectors,CdZnTe detector,radon emanometer,and gamma-ray dosimeter.By carefully controlling the experimental conditions and synergetic analysis of the measurement results,in conjunction with previous studies,we separated and determined the relative contributions induced by environmental radiation(4%),airborne radon and its daughters(2%),the normal radioactivity of human subjects arising from K-40(58%),cosmic rays(12%),and radioactivity in shielding materials and measuring instruments(24%).Furthermore,based on these results,we discuss practical guidelines to design a shielding room for body counters. 展开更多
关键词 Body counter Radiation background Shielding room In vivo measurement
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Performance Evaluation of Four Commercial Optical Particle Counters 被引量:1
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作者 Franco Belosi Gianni Santachiara Franco Prodi 《Atmospheric and Climate Sciences》 2013年第1期41-46,共6页
The performances of four optical particles counters, Aerosol Spectrometer (Grimm 1.108), Enviro Check (Grimm 1.107), DustMonit and ParticleScan, were evaluated in laboratory tests employing monodisperse aerosol partic... The performances of four optical particles counters, Aerosol Spectrometer (Grimm 1.108), Enviro Check (Grimm 1.107), DustMonit and ParticleScan, were evaluated in laboratory tests employing monodisperse aerosol particles. The study focused on how commercial instruments perform during routine measurements respect to OPC scientific understanding, because it is important for users of such instruments to be aware of their limitations. Measurements were performed using aerosol generated by a Monodisperse Aerosol Generator (MAGE), which produced carnauba wax particles of diameter (1.00 ± 0.08) μm and (1.40 ± 0.15) μm, and monodisperse Polystyrene Latex (PSL) aerosol with nominal diameter of 1.0mm. The results show comparable total particle number concentrations for all the counters, when the count of the first size channel (0.3 - 0.4 μm) for the 1.108 Grimm counter was left out. In the said channel the Grimm counter 1.108 always showed much higher particle counts than those inferred from the tested aerosols. The overcount was proved by the fact that the aerosol sampled in each test on a Nuclepore filter showed no particles in the 0.3 - 0.4 μm range when examined under Scanning Electronic Microscope (SEM). The presence of an artefact produced by the counter was assumed as a likely explanation. For all the counters, the Count Median Diameters (CMDs) of aerosol size distributions, were far below the expected value for the aerosol used. The nearest CMD values to the expected ones were shown by the Grimm 1.107 counter. 展开更多
关键词 Optical PARTICLE COUNTER Air quality AEROSOL SIZE Distribution
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Method to Measure Indoor Radon Concentration in an Open Volume with Geiger-Mueller Counters: Analysis from First Principles 被引量:2
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作者 M. P. Silverman 《World Journal of Nuclear Science and Technology》 2016年第4期232-260,共29页
A simple method employing a pair of pancake-style Geiger-Mueller (GM) counters for quantitative measurement of radon activity concentration (activity per unit volume) is described and demonstrated. The use of two GM c... A simple method employing a pair of pancake-style Geiger-Mueller (GM) counters for quantitative measurement of radon activity concentration (activity per unit volume) is described and demonstrated. The use of two GM counters, together with the basic theory derived in this paper, permit the detection of alpha particles from decay of and progeny ( <sup>218</sup>Po, <sup>214</sup>Po) and the conversion of the alpha count rate into a radon concentration. A unique feature of this method, in comparison with standard methodologies to measure radon concentration, is the absence of a fixed control volume. Advantages afforded by the reported GM method include: 1) it provides a direct in-situ value of radon level, thereby eliminating the need to send samples to an external testing laboratory;2) it can be applied to monitoring radon levels exhibiting wide short-term variability;3) it can yield short-term measurements of comparable accuracy and equivalent or higher precision than a commercial radon monitor sampling by passive diffusion;4) it yields long-term measurements statistically equivalent to commercial radon monitors;5) it uses the most commonly employed, overall least expensive, and most easily operated type of nuclear instrumentation. As such, the method is par-ticularly suitable for use by researchers, public health personnel, and home dwellers who prefer to monitor indoor radon levels themselves. The results of a consecutive 30-day sequence of 24 hour mean radon measurements by the proposed GM method and a commercial state-of-the-art radon monitor certified for radon testing are compared. 展开更多
关键词 RADIOACTIVITY Radon Concentration Geiger-Mueller Counter Alpha Particle Diffusion Alpha Range
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Fuzzy Reasoning Methods by Choosing Different Fuzzy Counters and Analysis of Effect
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作者 LIUFeng LIRen-jie 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第2期152-156,共5页
Different fuzzy reasoning methods were gave by choosing different fuzzy counters.This article generally introduced the basic structure of fuzzy controller,and compared and analysised the reasoning effect of fuzzy reas... Different fuzzy reasoning methods were gave by choosing different fuzzy counters.This article generally introduced the basic structure of fuzzy controller,and compared and analysised the reasoning effect of fuzzy reasoning methods and the effect of computer simulating control basicly on different fuzzy counters. 展开更多
关键词 Fuzzy counter fuzzy controlling fuzzy reasoning simulating control
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FeMoS_(4)/carbon fiber cloth composites:Preparation and application in dye-sensitized solar cells
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作者 ZHANG Qian ZHANG Yuxuan +3 位作者 YANG Yongguang BAI Ruijie LI Yuandong LI Ling 《无机化学学报》 北大核心 2025年第9期1916-1926,共11页
Herein,an FMS/CC composite was successfully fabricated by depositing FeMoS_(4)onto a pristine carbon fiber cloth(CC)substrate via a facile two-step hydrothermal method.The amorphous nature of the FMS/CC compos-ite end... Herein,an FMS/CC composite was successfully fabricated by depositing FeMoS_(4)onto a pristine carbon fiber cloth(CC)substrate via a facile two-step hydrothermal method.The amorphous nature of the FMS/CC compos-ite endows it with abundant catalytically active sites,thereby accelerating the reduction of I_(3)^(-).More importantly,the dye-sensitized solar cells(DSSCs)prepared by scraping it on flexible titanium mesh with low resistance had low series resistance(Rs).Electrochemical characterizations revealed that the DSSCs employing the FMS/CC counter electrode achieved a power conversion efficiency(PCE)of ca.9.51%(surpassing the ca.8.15%efficiency of the Pt counter electrode),open-circuit voltage(Voc)of ca.0.79 V,short-circuit current density(Jsc)of ca.18.31 mA·cm^(-2),and fill factor(FF)of ca.0.65.Moreover,after 100 times of cyclic voltammetry(CV)test,the CV curve remained unchanged,indicating the excellent stability of FMS/CC in the electrolyte containing I_(3)^(-)/I^(-). 展开更多
关键词 dye-sensitized solar cells transition metal sulfides counter electrode
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Otolith Degeneration with Aging:Insights from Video Ocular Counter-Roll(vOCR)Assessment
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作者 Melissa Castillo-Bustamante Jorge Madrigal +2 位作者 Elizabeth Andalón-Dueñas Johanna Marcela Vanegas Ireri Espinoza 《Journal of Otology》 2025年第3期198-203,共6页
Background:Vestibular assessments,such as the video ocular counter roll(vOCR)test,offer valuable insights into the interactions between age,otolith function,and vestibular performance.Objective:To analyze the relation... Background:Vestibular assessments,such as the video ocular counter roll(vOCR)test,offer valuable insights into the interactions between age,otolith function,and vestibular performance.Objective:To analyze the relation between age and vOCR gains as a potential marker of age-related otolith degeneration.Methods:A total of 107 participants underwent vOCR testing.Descriptive statistics and simple linear regression analyses were conducted to explore the association between age and vOCR gains.Results were presented using regression coefficients,95%confidence intervals,p-values,and R-squared values.Results:In the overall sample,statistically significant associations were observed between age and vOCR gains in both ears.For the right ear,vOCR gains decreased with increasing age(coefficient:-0.03;95%CI:-0.05 to-0.01;p<0.001;R^(2)=0.08),while the left ear showed a slightly stronger association(coefficient:-0.04;95%CI:-0.07 to-0.02;p<0.001;R²=0.12).These findings indicate a moderate age-related decline in otolith-mediated vestibular responses.Conclusion:vOCR gains appear to decline with age,reflecting potential age-related otolith degeneration.These results support the clinical value of vOCR as a non-invasive method to assess vestibular function and its changes across the lifespan. 展开更多
关键词 Otolith degeneration Video ocular counter roll vestibular disorders vestibular testing
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Commissioning of the fast neutron detector array at China Institute of Atomic Energy
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作者 Meng-Xiao Kang Ji-Zhi Zhang +4 位作者 Hong-Yi Wu Han-Xiong Huang Yu-Zhao Li He-Run Yang Xi-Chao Ruan 《Nuclear Science and Techniques》 2025年第5期102-112,共11页
The prompt fission neutron spectrum(PFNS)is a key nuclear data quantity that is of particular interest and plays a crucial role in understanding and modeling fission processes.An array comprising 48 liquid scintillati... The prompt fission neutron spectrum(PFNS)is a key nuclear data quantity that is of particular interest and plays a crucial role in understanding and modeling fission processes.An array comprising 48 liquid scintillation detectors and a parallelplate avalanche counter(PPAC)was developed at the China Institute of Atomic Energy(CIAE)to measure the PFNS of actinide nuclei.Efficiency and energy calibrations were performed for all the liquid scintillators,and their efficiencies were consistently found to be better than 5%.The time resolutions of the PPAC and liquid scintillators were measured to be 1.08 ns and 1.16 ns using~(252)Cf and~(207)Bi sources,respectively.The pulse shape discrimination of the liquid scintillator was utilized to identify neutron andγsignals on an event-by-event basis,and the figure of merit was deduced as 1.12 at a 200 ke Vee threshold.The contribution to the PFNS from multiple scattered neutrons was evaluated via Geant4 simulations,and those originating from the environment were found to be comparable to the crosstalk between the detectors.The neutron efficiency of the entire detection array was calibrated using a~(252)Cf spontaneous fission source and was demonstrated to be consistent with the Geant4 simulation results,which verified the reliability of the detection array. 展开更多
关键词 Liquid scintillation detector Parallel Plate Avalanche Counter(PPAC) Prompt Fission Neutron Spectra(PFNS) Neutron detector array
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Use counters to model the addition of integers
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《中学生数学(初中版)》 2019年第8期49-49,共1页
HANDS-ON LAB You can use positive and negative counters to model the addition of integers.The counter + represents 1,and the counter - represents-1.Remember that addition means combining two sets.ACTIVITY Work with a ... HANDS-ON LAB You can use positive and negative counters to model the addition of integers.The counter + represents 1,and the counter - represents-1.Remember that addition means combining two sets.ACTIVITY Work with a partner. 展开更多
关键词 USE counters MODEL the ADDITION INTEGERS
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EFFECT OF PARTICLE REFRACTIVE INDEX ON THE ACCURACY OF AEROSOL MEASUREMENT WITH OPTICAL PARTICLE COUNTERS 被引量:2
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作者 胡欢陵 赵凤生 龚知本 《Chinese Science Bulletin》 SCIE EI CAS 1988年第5期428-432,共5页
The optical particle counter (OPC) is widely used in the measurement of aerosol. The calculation results of response curves for several commercial counters indicate that these curves are quite sensitive to the refract... The optical particle counter (OPC) is widely used in the measurement of aerosol. The calculation results of response curves for several commercial counters indicate that these curves are quite sensitive to the refractive index, especially to its imaginary part. If the particle sizes were determined with the cali- 展开更多
关键词 AEROSOL imaginary SIZES refractive radius COUNTER RESULTANT SPHERES LATEX calibration
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Interference Analysis of Co-Located Container Workloads:A Perspective from Hardware Performance Counters
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作者 Wen-Yan Chen Ke-Jiang Ye +2 位作者 Cheng-Zhi Lu Dong-Dai Zhou Cheng-Zhong Xu 《Journal of Computer Science & Technology》 SCIE EI CSCD 2020年第2期412-417,共6页
Workload characterization is critical for resource management and scheduling.Recently,with the fast development of container technique,more and more cloud service providers like Google and Alibaba adopt containers to ... Workload characterization is critical for resource management and scheduling.Recently,with the fast development of container technique,more and more cloud service providers like Google and Alibaba adopt containers to provide cloud services,due to the low overheads.However,the characteristics of co-located diverse services(e.g.,interactive on-line services,off-line computing services)running in containers are still not clear.In this paper,we present a comprehensive analysis of the characteristics of co-located workloads running in containers on the same server from the perspective of hardware events.Our study quantifies and reveals the system behavior from the micro-architecture level when workloads are running in different co-location patterns.Through the analysis of typical hardware events,we provide recommended/unrecommended co-location workload patterns which provide valuable deployment suggestions for datacenter administrators. 展开更多
关键词 WORKLOAD characterization CONTAINER CO-LOCATION pattern HARDWARE performance COUNTER
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高校图书馆电子资源使用情况分析研究——以山西师范大学外文数据库为例 被引量:1
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作者 万莉 孙德福 刘士义 《甘肃科技》 2024年第1期102-105,共4页
高校图书馆电子资源为高校师生教学与科研提供了稳定且系统的文献资源保障。对高校师生电子资源的使用情况进行统计与分析研究,既可以为高校图书馆及其主管部门提供科学管理、合理决策与有效评估等数据参考,也可为高校图书馆合理建设馆... 高校图书馆电子资源为高校师生教学与科研提供了稳定且系统的文献资源保障。对高校师生电子资源的使用情况进行统计与分析研究,既可以为高校图书馆及其主管部门提供科学管理、合理决策与有效评估等数据参考,也可为高校图书馆合理建设馆藏数字资源提供依据。文章以山西师范大学图书馆电子数据资源为例,选出7个外文数据库进行量化数据分析。根据外文数据库提供的COUNTER报告,从数据库篇均成本、读者的使用需求和使用规律方面进行评价和分析,以期为其他图书馆合理购置电子资源提供建议。 展开更多
关键词 高校图书馆 电子资源 外文数据库 COUNTER 评价和分析
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Coupled funnel control for supersonic tailless aerial vehicle on penetrating counter air
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作者 Yingyang WANG Peng ZHANG +1 位作者 Jilian GUO Jianbo HU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第7期458-481,共24页
Supersonic Tailless Aerial Vehicles(STAVs)will become an essential force in Penetrating Counter Air(PCA),but STAVs do not have the traditional horizontal and vertical tails,making pitch and yaw control difficult.The a... Supersonic Tailless Aerial Vehicles(STAVs)will become an essential force in Penetrating Counter Air(PCA),but STAVs do not have the traditional horizontal and vertical tails,making pitch and yaw control difficult.The attack angle and the sideslip angle need to be limited to ensure that the engine inlet and the aerodynamic rudder at the rear of the vehicle can work properly,which is the so-called security constraints.In addition,the tracking error of the aerodynamic angle needs to be limited to achieve effective attitude control or high-accuracy tracking of trajectories,which is the so-called performance constraints.To this end,an attitude control method that meets the needs of PCA has been devised,based on constraint definition,coupled constraints handling,and control law design.Firstly,mathematical descriptions of the security constraints,performance constraints,and control constraints are given.Secondly,two treatment methods,coupled command filter and coupled funnel control are proposed for the aerodynamic angle coupled constraint problem.Finally,based on Nonlinear Dynamic Inverse(NDI)design,the coupled funnel controller is designed and validated by simulation for two typical mission scenarios,high-altitude penetration and low-altitude surprise defence.The proposed control method not only satisfies the security and performance constraints of STAV attitude control but also is highly robust. 展开更多
关键词 Supersonic tailless aircraft Penetrating counter air Funnel control Attitude control Control allocation
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ZIF-67 derived C&Co counter electrode in dye-sensitized solar cells
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作者 SUN Zhenfan HE Yunxiao +1 位作者 QIAO Xiaodong LEI Bingxin 《分子科学学报》 CAS 2024年第3期239-246,共8页
ZIF-67 containing cobalt cation was selected as the research object,and the carbon-containing cobalt matrix nanocomposite(C&Co)was obtained after heat treatment in a nitrogen atmosphere at the appropriate temperat... ZIF-67 containing cobalt cation was selected as the research object,and the carbon-containing cobalt matrix nanocomposite(C&Co)was obtained after heat treatment in a nitrogen atmosphere at the appropriate temperature.The nanostructures and morphologies of the nanocomposite were analyzed by X-ray diffraction,field emission scanning electron microscopy,transmission electron microscopy,and X-ray photoelectron spectroscopy.The electrochemical response was comprehensively characterized by cyclic voltammetry,electrochemical impedance spectroscopy,and Tafel polarization.The electrochemical analysis of the C&Co nanocomposite electrode shows that the electrode has an obvious electrocatalytic activity for the reduction of the triiodide compound.The conversion efficiency of dye-sensitized solar cells prepared with C&Co nanocomposite electrode shows 5.3%under the condition of AM1.5G simulated sunlight irradiation,which shows great application potential in Pt-free electrode materials. 展开更多
关键词 dye-sensitized solar cells counter electrode MOFS C&Co nanocomposite
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Flow Rate Measurement of Gravity Infusion Set and Functional Evaluation of Drop Counter: A Pilot Study
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作者 Rina Sakai Shuichi Tanaka +3 位作者 Kaya Murakami Tomomi Mizuhashi Kazuhiro Yoshida Masanobu Ujihira 《Journal of Biomedical Science and Engineering》 2024年第7期129-135,共7页
Developing a novel drop counter by introducing the Internet of Things concept has been vigorously conducted in recent years. Understanding the newly introduced drop counter’s flow rate control accuracy and flow rate ... Developing a novel drop counter by introducing the Internet of Things concept has been vigorously conducted in recent years. Understanding the newly introduced drop counter’s flow rate control accuracy and flow rate count feature is essential for improving safety in infusion management. This study aimed to verify if the new drop counters could secure accurate flow rate and drip count by conducting actual flow rate measurements using gravimetry and functional evaluation. A drop counter was attached to each drip chamber of the infusion set, and an IV drip was conducted at the 100 ml/h flow rate. The weight of discharged physiological saline was measured to plot trumpet curves. Next, three different types of drop counters were evaluated to determine if they maintained drip count accuracy according to the changes in their position angles. The flow rate errors in all conditions indicated trumpet-like curves, exhibiting an overall error range within ±10% in all observation windows. Although every drop counter successfully detected and measured dripping, it was challenging in some counters to detect dripping when the drip chamber was tilted. In comparing adult and pediatric IV sets, the adult IV set was found to be less likely to detect dripping in the angled position. No significant differences in results were confirmed between high and low flow rates, suggesting that the drop count function would not be affected by the flow rate in the ranges of typical infusion practices. Doppler sensors have a wide range of measurements and high sensitivity;the dripping was detected successfully even when the drip chamber was tilted, probably due to the advantages of these sensors. In contrast, miscounts occurred in those equipped with infrared sensors, which could not detect light intensity changes in tilted positions. Understanding the tendencies in flow rate errors in infusion can be valuable information for infusion management. 展开更多
关键词 Gravity Infusion Set Drop Counter IV Fluids Flow Rate Trumpet Curves
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基于通用PC架构的高精度网络时延测量方法 被引量:30
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作者 黎文伟 张大方 +1 位作者 谢高岗 杨金民 《软件学报》 EI CSCD 北大核心 2006年第2期275-284,共10页
时延是准确测量时延抖动、带宽等网络性能指标的基础.目前的时延测量方法由于存在时钟误差和位置误差因而精度较差.提出一种改进的时延测量方法,以TSC(time stamp counter)寄存器取代系统时钟计时来消除测量的时钟误差,将时间戳... 时延是准确测量时延抖动、带宽等网络性能指标的基础.目前的时延测量方法由于存在时钟误差和位置误差因而精度较差.提出一种改进的时延测量方法,以TSC(time stamp counter)寄存器取代系统时钟计时来消除测量的时钟误差,将时间戳记录位置由应用程序转移到网卡驱动来消除位置误差,极大地提高了时延测量精度.实验结果表明,与传统方法相比,不同包长度下,所提出的方法可降低测量误差21%~150%,且测量结果稳定,对系统吞吐量基本无影响.该方法基于通用PC架构,测量成本低,适于普遍采用. 展开更多
关键词 时延测量 网络测量 主动测量 TSC(time STAMP counter)
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大长高比腔体内的混合流体行进波对流 被引量:7
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作者 宁利中 齐昕 +2 位作者 魏炳乾 原田义文 八幡英雄 《水动力学研究与进展(A辑)》 CSCD 北大核心 2006年第4期427-432,共6页
该文报告大长高比腔体(Γ=46)中强非线性状态(Ψ=-0.47)混合流体行进波对流图案的数值模拟结果。利用MAC法通过二维流体力学扰动方程组进行了数值模拟。获得了发生在对流发生点附近的线性Counter propagating wave,出现在分叉图非线性... 该文报告大长高比腔体(Γ=46)中强非线性状态(Ψ=-0.47)混合流体行进波对流图案的数值模拟结果。利用MAC法通过二维流体力学扰动方程组进行了数值模拟。获得了发生在对流发生点附近的线性Counter propagating wave,出现在分叉图非线性分支上的均匀行进波和发生在分叉图sadd le-node附近的局部行进波状态等三种行进波对流图案,并探讨了它们的稳定性。最后将数值模拟结果与实验结果进行了比较。 展开更多
关键词 混合流体 行进波 COUNTER PROPAGATING WAVE 均匀行进波 局部行进波
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基于COUNTER的电子资源使用统计中的标准问题探讨与研究 被引量:26
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作者 张计龙 殷沈琴 汪东伟 《图书馆理论与实践》 CSSCI 北大核心 2016年第5期95-100,共6页
针对当前电子资源使用统计中普遍存在的标准不一,统计数据不全,无法进行电子资源横向比较的问题,提出基于COUNTER规范和网络底层技术,从图书馆端进行电子资源使用统计的创新解决思路。以复旦大学图书馆为例,对电子资源使用统计中的COUN... 针对当前电子资源使用统计中普遍存在的标准不一,统计数据不全,无法进行电子资源横向比较的问题,提出基于COUNTER规范和网络底层技术,从图书馆端进行电子资源使用统计的创新解决思路。以复旦大学图书馆为例,对电子资源使用统计中的COUNTER标准实施问题进行分析探讨并给出了实证,对COUNTER规范提出改进建议,具有推广应用价值。 展开更多
关键词 电子资源 使用统计 COUNTER ERU SUSHI
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COUNTER Release 5的新特征及其应用研究 被引量:13
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作者 杨巍 叶仁杰 +1 位作者 吴元业 林伟明 《大学图书馆学报》 CSSCI 北大核心 2020年第1期18-25,41,共9页
COUNTER Release 5旨在应对不断变化的电子资源,提供可靠、一致和可对比的使用统计数据。文章分析了COUNTER Release 5的规范并探索其在中国高校图书馆数字资源采购联盟(DRAA)中的应用。研究发现,与COUNTER Release 4相比,Release 5有... COUNTER Release 5旨在应对不断变化的电子资源,提供可靠、一致和可对比的使用统计数据。文章分析了COUNTER Release 5的规范并探索其在中国高校图书馆数字资源采购联盟(DRAA)中的应用。研究发现,与COUNTER Release 4相比,Release 5有了明显的变化,包括定义了全新的报告体系、统计指标类型、RESTful SUSHI接口等技术细节。为在DRAA中应用COUNTER Release 5,需要从两个方面改进:一是让统计模块兼容COUNTER Release 5的数据模型,使COUNTER Release 5的统计数据可以融入现有的统计模型;二是需要新增RESTful SUSHI接口的客户端及文件解析器,让系统可以获取并解析到COUNTER Release 5的报告。 展开更多
关键词 COUNTER RELEASE 5 SUSHI 使用统计
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