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Influences of rainfall infiltration on stability of accumulation slope by in-situ monitoring test 被引量:9
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作者 周中 王宏贵 +1 位作者 傅鹤林 刘宝琛 《Journal of Central South University》 SCIE EI CAS 2009年第2期297-302,共6页
In order to improve the understanding of the fundamental mechanism of rainfall infiltration induced landslides in accumulation slope and to clarify some important characteristics of slope performance,artificial rainfa... In order to improve the understanding of the fundamental mechanism of rainfall infiltration induced landslides in accumulation slope and to clarify some important characteristics of slope performance,artificial rainfall simulation tests and field synthetic monitoring were carried out on a typical accumulation slope of Shangrui Freeway in Guizhou Province,China.The monitoring results show that the most accumulation landslides caused by rainfall infiltration are shallow relaxation failure,whose deformation zone lies within the top 0-4 m soil layer.The deformation of slope gradually reduces from the surface,where the greatest deformation lies in,to the deep part of slope.The average percentage of infiltration during the first 2 h is 86%,and then it reduces gradually with time because of the increase of the surface runoff.The average percentage of infiltration drop to a relatively stable value(50%)after 6 h.Rainfall infiltration causes obvious increase of pore-water pressure,which may result in a reduction of shear strength due to a decrease in effective stress and wetting-induced softening.The double-effect of rainfall infiltration is the main reason of rainfall infiltration induced landslides in accumulation slope. 展开更多
关键词 accumulation slope STABILITY rainfall infiltration in-situ monitoring
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Interplay of laser power and pore characteristics in selective laser melting of ZK60 magnesium alloys:A study based on in-situ monitoring and image analysis 被引量:1
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作者 Weijie Xie Hau-Chung Man Chi-Wai Chan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1346-1366,共21页
This study offers significant insights into the multi-physics phenomena of the SLM process and the subsequent porosity characteristics of ZK60 Magnesium(Mg)alloys.High-speed in-situ monitoring was employed to visualis... This study offers significant insights into the multi-physics phenomena of the SLM process and the subsequent porosity characteristics of ZK60 Magnesium(Mg)alloys.High-speed in-situ monitoring was employed to visualise process signals in real-time,elucidating the dynamics of melt pools and vapour plumes under varying laser power conditions specifically between 40 W and 60 W.Detailed morphological analysis was performed using Scanning-Electron Microscopy(SEM),demonstrating a critical correlation between laser power and pore formation.Lower laser power led to increased pore coverage,whereas a denser structure was observed at higher laser power.This laser power influence on porosity was further confirmed via Optical Microscopy(OM)conducted on both top and cross-sectional surfaces of the samples.An increase in laser power resulted in a decrease in pore coverage and pore size,potentially leading to a denser printed part of Mg alloy.X-ray Computed Tomography(XCT)augmented these findings by providing a 3D volumetric representation of the sample internal structure,revealing an inverse relationship between laser power and overall pore volume.Lower laser power appeared to favour the formation of interconnected pores,while a reduction in interconnected pores and an increase in isolated pores were observed at higher power.The interplay between melt pool size,vapour plume effects,and laser power was found to significantly influence the resulting porosity,indicating a need for effective management of these factors to optimise the SLM process of Mg alloys. 展开更多
关键词 Selective laser melting(SLM) Magnesium(Mg)alloys Biodegradable implants POROSITY in-situ monitoring
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Technical development of operational in-situ marine monitoring and research on its key generic technologies in China 被引量:1
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作者 Yunzhou Li Juncheng Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第10期117-126,共10页
In China,operational in-situ marine monitoring is the primary means of directly obtaining hydrological,meteorological,and oceanographic environmental parameters across sea areas,and it is essential for applications su... In China,operational in-situ marine monitoring is the primary means of directly obtaining hydrological,meteorological,and oceanographic environmental parameters across sea areas,and it is essential for applications such as forecast of marine environment,prevention and mitigation of disaster,exploitation of marine resources,marine environmental protection,and management of transportation safety.In this paper,we summarise the composition,development courses,and present operational status of three systems of operational in-situ marine monitoring,namely coastal marine automated network station,ocean data buoy and voluntary observing ship measuring and reporting system.Additionally,we discuss the technical development in these in-situ systems and achievements in the key generic technologies along with future development trends. 展开更多
关键词 marine observation technology operational in-situ marine monitoring C-MAN station ocean data buoy VOS measuring and reporting system achievements in the key technologies development trend
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Design and feasibility analysis of a new completion monitoring technical scheme for natural gas hydrate production tests
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作者 Qiu-ping Lu Yan-jiang Yu +8 位作者 Xie Wen-wei Jin-qiang Liang Jing-an Lu Ben-chong Xu Hao-xian Shi Hao-yu Yu Ru-lei Qin Xing-chen Li Bin Li 《China Geology》 CAS CSCD 2023年第3期466-475,共10页
As a prerequisite and a guarantee for safe and efficient natural gas hydrates(NGHs)exploitation,it is imperative to effectively determine the mechanical properties of NGHs reservoirs and clarify the law of the change ... As a prerequisite and a guarantee for safe and efficient natural gas hydrates(NGHs)exploitation,it is imperative to effectively determine the mechanical properties of NGHs reservoirs and clarify the law of the change in the mechanical properties with the dissociation of NGHs during NGHs production tests by depressurization.Based on the development of Japan’s two offshore NGHs production tests in vertical wells,this study innovatively proposed a new subsea communication technology-accurate directional connection using a wet-mate connector.This helps to overcome the technical barrier to the communication between the upper and lower completion of offshore wells.Using this new communication technology,this study explored and designed a mechanical monitoring scheme for lower completion(sand screens).This scheme can be used to monitor the tensile stress and radial compressive stress of sand screens caused by NGHs reservoirs in real time,thus promoting the technical development for the rapid assessment and real-time feedback of the in-situ mechanical response of NGHs reservoirs during offshore NGHs production tests by depressurization. 展开更多
关键词 Natural gas hydrates Depressurization test Wet-mate Directional connection Lower completion monitoring in-situ mechanical response of reservoirs Oil-gas exploration engineering The South China Sea
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Study of the Effect of Bacterial Resistance Monitoring in Clinical Microbiology Testing
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作者 Lingfeng Lu Jie Mou +1 位作者 Kun Wu Ju Luo 《Journal of Clinical and Nursing Research》 2023年第6期131-136,共6页
Objective:To observe and analyze the effect of bacterial resistance monitoring in clinical microbiology testing.Methods:600 microbial specimens collected in our hospital in the past year(April 2021 to April 2022)were ... Objective:To observe and analyze the effect of bacterial resistance monitoring in clinical microbiology testing.Methods:600 microbial specimens collected in our hospital in the past year(April 2021 to April 2022)were used as the test subjects of this study.The specimens were divided into Group A(control group)and Group B(research group),with 300 cases in each group.Group A consisted of blood culture specimens,while Group B consisted of sputum specimens.After the tests were completed,the rates of unfavorable and favorable results,bacterial species distribution,and bacterial drug resistance of the specimens in both groups were compared.Results:Among group A specimens,29 cases were positive(9.67%)and 271 cases were negative(90.33%);among group B specimens,99 cases were positive(33.00%)and 201 cases were negative(66.00%);the difference between the two groups of data was statistically significant(P<0.05).As for the distribution of the types of bacteria,there were 472 cases of Gram-negative bacteria and 128 cases of Gram-positive bacteria.Conclusion:Bacterial resistance monitoring is helpful in clinical microbiology testing.Through proper monitoring,bacterial resistance can be well understood.In this way,patients get to receive appropriate treatment measures and suitable antibacterial prescriptions,thereby improving the patient outcome. 展开更多
关键词 Bacterial resistance monitoring Clinical microbiology testing Application value
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Stability monitoring and evaluation of the modeled test square for prehistoric earthen sites during excavation period 被引量:3
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作者 谌文武 戴鹏飞 +3 位作者 张景科 陈鹏飞 郭青林 孙满利 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期464-471,共8页
In order to explore the stability of test square during archaeological excavation for prehistoric earthen sites in Hangzhou, a modeled test square with 2. 3 min depth, inplane dimensions of 5 min width by 5 m in lengt... In order to explore the stability of test square during archaeological excavation for prehistoric earthen sites in Hangzhou, a modeled test square with 2. 3 min depth, inplane dimensions of 5 min width by 5 m in length, and an archaeological column in the middle was excavated by means of a top-down excavation technique. To investigate the stability performance of the modeled test square and the associated effect on the adjacent area, a real-time comprehensive instrumentation program was conducted during the excavation. Field observations included ground settlements, lateral displacement, pore pressure and underground water level. Monitoring data indicates that the ground settlement induced by dewatering and unloading action basically decreases with the increase of the distance away from the pit edge, and the lateral displacements at four sides showa nonlinear variation along the depth. The maximum value is far below the acceptable value regulated by the related standard,which validates the stability of the modeled test square during excavation. Variations of pore pressure and water level suggest that long-term stability should be paid more attention due to the slowconsolidation of soft soil. Meanwhile, it is proved that the step shape of the wall can resist lateral displacement more effectively than the vertical shape of wall. This case study provides insights into the real archaeological excavation in Hangzhou, in particular Liangzhu prehistoric earthen sites. 展开更多
关键词 prehistoric earthen sites archaeological excavation test square stability monitoring
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Importance of Proficiency Testing in Water Quality Monitoring 被引量:2
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作者 郭正 向哲涛 宋华力 《Agricultural Science & Technology》 CAS 2014年第12期2201-2203,共3页
The monitoring data is undoubtedly important to the water quality monitor- ing department. The proficiency testing is an important way to improve the monitor- ing capacity and enhance the quality management of laborat... The monitoring data is undoubtedly important to the water quality monitor- ing department. The proficiency testing is an important way to improve the monitor- ing capacity and enhance the quality management of laboratories. It plays an impor- tant role in ensuring the accuracy, integrity and comparability of monitoring data. In this paper, the positive role of proficiency testing in the water quality monitoring was analyzed. In addition, how to improve the water quality monitoring capacity and the quality management level of laboratories through the proficiency testing was also discussed. 展开更多
关键词 Proficiency testing Water quality monitoring Management level
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Piezomagnetic In-situ Stress Monitoring and its Application in the Longmenshan Fault Zone 被引量:4
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作者 ZHANG Chongyuan WU Manlu +1 位作者 CHEN Qunce LIAO Chunting 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1592-1602,共11页
The relative change of in-situ stress is an inevitable outcome of differential movement among the crust plates. Conversely, changes of in-situ stress can also lead to deformation and instability of crustal rock mass, ... The relative change of in-situ stress is an inevitable outcome of differential movement among the crust plates. Conversely, changes of in-situ stress can also lead to deformation and instability of crustal rock mass, trigger activity of faults, and induce earthquakes. Hence, monitoring real-time change of in-situ stress is of great significance. Piezomagnetic in-situ stress monitoring has good and longtime applications in large engineering constructions and geoscience study fields in China. In this paper, the new piezomagnetic in-situ stress monitoring system is introduced and it not only has overall improvements in measuring cell's structure and property, stressing and orienting way, but also enhances integration and intelligence of control and data transmission system, in general, which greatly promotes installing efficiency of measuring probe and quality of monitoring data. This paper also discusses the responses of new piezomagnetic system in large earthquake events of in-situ stress monitoring station at Qiaoqi of Baoxing and Wenxian of Gansu. The monitoring data reflect adjustments and changes of tectonic stress field at the southwestern segment of and the northern area near the Longmenshan fault zone, which shows that the new system has a good performance and application prospect in the geoscience field. Data of the Qiaoqi stress-monitoring station manifest that the Lushan Earthquake did not release stress of the southwestern segment of the Longmenshan fault zone adequately and there still probably exists seismic risk in this region in the future. Combined with absolute in-situ stress measurement, carrying out long-term in-situ stress monitoring in typical tectonic position of important regions is of great importance for researchers to assess and study regional crust stability. 展开更多
关键词 in-situ stress monitoring new piezomagnetic in-situ stress monitoring system theLongmenshan fault zone regional stress field dynamic changes
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Research progress and application of deep in-situ condition preserved coring and testing
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作者 Heping Xie Yunqi Hu +14 位作者 Mingzhong Gao Ling Chen Ru Zhang Tao Liu Feng Gao Hongwei Zhou Xiaobo Peng Xiongjun Li Jianbo Zhu Cunbao Li Ruidong Peng Yanan Gao Cong Li Jianan Li Zhiqiang He 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第11期1319-1337,共19页
With the depletion of shallow resources,the exploration of deep earth resources has become a global strategy.The study of the different patterns in the physical mechanical properties of rocks at different occurrence d... With the depletion of shallow resources,the exploration of deep earth resources has become a global strategy.The study of the different patterns in the physical mechanical properties of rocks at different occurrence depths is the basis for exploring deep into the earth,with the core and premise being the acquisition and testing of deep in-situ core specimens.Based on the original idea of deep in-situ condition preserved coring(ICP-Coring)and testing,combined with theoretical modeling,numerical analysis,test platform development,indoor testing and engineering application,the principles and technologies of deep ICP-Coring are developed.This principle and technology consists of five parts:in-situ pressurepreserved coring(IPP-Coring),in-situ substance-preserved coring(ISP-Coring),in-situ temperaturepreserved coring(ITP-Coring),in-situ light-preserved coring(ILP-Coring),and in-situ moisturepreserved coring(IMP-Coring).The theory and technology of temperature and pressure reconstruction at different occurrence depths and in different environments are proposed,and prototype trial production was completed by following the principle of displacement and tests based on the in-situ reconstructed environment.The notable advances are as follows:(1)Deep in-situ coring system:A pressure-preserved controller with an ultimate bearing capacity greater than 140 MPa,highperformance(temperature-resistant,pressure-resistant,and low thermally conductive)temperaturepreserved materials,an active temperature control system,and high-barrier quality-preserved membrane materials were developed;a deep ICP-Coring capacity calibration platform was independently developed,a deep in-situ coring technology system was developed,and the acquisition of deep in-situ cores was realized.(2)In-situ storage displacement system:Following the dual-circuit hydraulic design idea,a single-drive source push-pull composite grabbing mechanism was designed;the design of the overall structure for the deep in-situ displacement storage system and ultrahigh pressure cabin structure was completed,which could realize docking the coring device and core displacement in the in-situ reconstructed environment.(3)Test analysis system:A noncontact acoustic-electric-magnetic test system was developed under the in-situ reconstructed environment,and the errors between the test results and traditional contact test results were mostly less than 10%;a detachable deep in-situ core true triaxial test system was developed,which could perform loading tests for deep in-situ cores.The relevant technological achievements were successfully applied to the exploration and development of deep resources,such as deep mines,deep-sea natural gas hydrates,and deep oil and gas.The research results provide technical and equipment support for the construction of a theoretical system for deep in-situ rock mechanics,the development of deep earth resources and energy,and the scientific exploration of different layers and occurrence depths(deep and ultradeep)of the Earth. 展开更多
关键词 Deep mining Deep in-situ CORING DISPLACEMENT test
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Process Monitoring and Terminal Verification of Cable-Stayed Bridges with Corrugated Steel Webs under Contruction
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作者 Kexin Zhang Xinyuan Shen +1 位作者 Longsheng Bao He Liu 《Structural Durability & Health Monitoring》 EI 2023年第2期131-158,共28页
In this paper,the construction process of a cable-stayed bridge with corrugated steel webs was monitored.Moreover,the end performance of the bridge was verified by load test.Owing to the consideration of the bridge st... In this paper,the construction process of a cable-stayed bridge with corrugated steel webs was monitored.Moreover,the end performance of the bridge was verified by load test.Owing to the consideration of the bridge structure safety,it is necessary to monitor the main girder deflection,stress,construction error and safety state during construction.Furthermore,to verify whether the bridge can meet the design requirements,the static and dynamic load tests are carried out after the completion of the bridge.The results of construction monitoring show that the stress state of the structure during construction is basically consistent with the theoretical calculation and design requirements,and both meet the design and specification requirements.The final measured stress state of the structure is within the allowable range of the cable-stayed bridge,and the stress state of the structure is normal and meets the specification requirements.The results of load tests show that the measured deflection values of the mid-span section of the main girder are less than the theoretical calculation values.The maximum deflection of the girder is−20.90 mm,which is less than−22.00 mm of the theoretical value,indicating that the girder has sufficient structural stiffness.The maximum impact coefficient under dynamic load test is 1.08,which is greater than 1.05 of theoretical value,indicating that the impact effect of heavy-duty truck on this type of bridge is larger.This study can provide important reference value for construction and maintenance of similar corrugated steel web cable-stayed bridges. 展开更多
关键词 Cable-stayed bridge corrugated steel web construction monitoring static load test dynamic load test
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Numerical analysis and field monitoring tests on shallow tunnels under weak surrounding rock 被引量:2
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作者 刘建华 刘晓明 +1 位作者 张永杰 肖庭 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期4056-4063,共8页
The Jianpudong No. 4 tunnel is a shallow tunnel, which belongs to Shaoshan County scenic highway in Hunan province, China and whose surrounding rock is weak. According to its characteristics, the field monitoring test... The Jianpudong No. 4 tunnel is a shallow tunnel, which belongs to Shaoshan County scenic highway in Hunan province, China and whose surrounding rock is weak. According to its characteristics, the field monitoring tests and numerical analysis were done. The mechanical characteristics of shallow tunnels under weak surrounding rock and the stress-strain rule of surrounding rock and support were analyzed. The numerical analysis results show that the settlement caused by upper bench excavating accounts for 44% of the total settlement, and the settlement caused by tunnel upper bench supporting accounts for 56% of the total settlement. The maximum axial force of shotcrete lining is 177.2 k N, which locates in hance under the secondary lining. The maximum moment of shotcrete lining is 5.08 k N·m, which locates in the arch foot. The stress curve of steel arch has three obvious stages during the tunnel construction. The maximum axial force of steel arch is 297.4 k N, which locates in tunnel vault. The axial forces of steel arch are respectively 23.5 k N and-21.8 k N, which is influenced by eccentric compression of shallow tunnel and locates in hance. The results show that there is larger earth pressure in tunnel vault which is most unfavorable position of steel arch. Therefore, the advance support should be strengthened in tunnel vault during construction process. 展开更多
关键词 tunnel engineering shallow tunnel weak surrounding rock numerical analysis field monitoring tests
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Six-year analysis of key monitoring for bacterial strain distribution and antibiotic sensitivity in a hospital
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作者 Zong-Ying Li Dong Yang Chong-Hua Hao 《World Journal of Clinical Cases》 SCIE 2023年第30期7294-7301,共8页
BACKGROUND With the widespread use of antimicrobial drugs,bacterial resistance has become a significant problem,posing a serious threat to public health.The prevalence of clinical infection strains in hospitals and th... BACKGROUND With the widespread use of antimicrobial drugs,bacterial resistance has become a significant problem,posing a serious threat to public health.The prevalence of clinical infection strains in hospitals and their drug sensitivities are key to the appropriate use of antibiotics in clinical practice.AIM To identify prevalent bacteria and their antibiotic resistance profiles in a hospital setting,thereby guiding effective antibiotic usage by clinicians.METHODS Specimens from across the institution were collected by the microbiology laboratory.The VITEK 2 compact fully automatic analyzer was used for bacterial identification and antibiotic sensitivity testing,and the WHONET5.6 software was utilized for statistical analysis.RESULTS A total of 12062 bacterial strains of key monitoring significance were detected.Staphylococcus aureus demonstrated widespread resistance to penicillin,but none of the strains were resistant to vancomycin or linezolid.Moreover,219 strains of methicillin-resistant coagulase-negative staphylococci and 110 strains of methicillin-resistant Staphylococcus aureus were detected.Enterococcus faecalis showed moderate resistance to the third-generation quinolones ciprofloxacin and levofloxacin,but its resistance to nitrofurantoin and tetracycline was low.Enterococcus faecium displayed significantly lower resistance to third-and fourthgeneration quinolones than Enterococcus faecalis.The resistance of two key monitoring strains,Escherichia coli and Klebsiella pneumoniae,to piperacillin/tazobactam was 5%-8%.However,none of the Escherichia coli and Klebsiella pneumoniae strains were resistant to meropenem.The resistance of Acinetobacter baumannii to piperacillin/sulbactam was nearly 90%.Nonetheless,the resistance to tigecycline was low,and Pseudomonas aeruginosa demonstrated minimal resistance in the antibiotic sensitivity test,maintaining a resistance of<10%to the cephalosporin antibiotics cefotetan and cefoperazone over the last 6 years.The resistance to amikacin remained at 0.2%over the past 3 years.CONCLUSION Our hospital’s overall antibiotic resistance rate was relatively stable from 2017 to 2022.The detection rates of key monitoring strains are reported quarterly and their resistance dynamics are monitored and communicated to the entire hospital,which can guide clinical antibiotic selection. 展开更多
关键词 Antibiotic sensitivity test monitoring bacterial antibiotic resistance Antimicrobial drugs Antimicrobial stewardship Combination therapies Antibiotic stewardship
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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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Health condition monitoring with multiple physical signals in tensile test for double-material friction welding
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作者 张玉波 徐滨士 +2 位作者 王海斗 杨大祥 朱丽娜 《Journal of Central South University》 SCIE EI CAS 2012年第10期2705-2711,共7页
The manifold physical signals including micro resistance,infrared thermal signal and acoustic emission signal in the tensile test for double-material friction welding normative samples were monitored and collected dyn... The manifold physical signals including micro resistance,infrared thermal signal and acoustic emission signal in the tensile test for double-material friction welding normative samples were monitored and collected dynamically by TH2512 micro resistance measuring apparatus,flir infrared thermal camera and acoustic emission equipment which possesses 18 bit PCI-2 data acquisition board.Applied acoustic emission and thermal infrared NDT(non-destructive testing) means were used to verify the feasibility of using resistance method and to monitor dynamic damage of the samples.The research of the dynamic monitoring system was carried out with multi-information fusion including resistance,infrared and acoustic emission.The results show that the resistance signal,infrared signal and acoustic emission signal collected synchronously in the injury process of samples have a good mapping.Electrical,thermal and acoustic signals can more accurately capture initiation and development of micro-defects in the sample.Using dynamic micro-resistance method to monitor damage is possible.The method of multi-information fusion monitoring damage possesses higher reliability,which makes the establishing of health condition diagnosing and early warning platform with multiple physical information monitoring possible. 展开更多
关键词 micro resistance pictorial infrared photography acoustic emission nondestructive testing dynamic monitoring
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Can pH Monitoring Predict Gastric Emptying Measured by <sup>13</sup>C-Acetate Breath Test in Gastroesophageal Reflux with Neurological Impairment?
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作者 Tadao Okada Shohei Honda +2 位作者 Hisayuki Miyagi Masashi Minato Akinobu Taketomi 《Surgical Science》 2014年第1期20-24,共5页
Introduction: Delayed gastric emptying (DGE) often occurs in patients with gastroesophageal reflux (GER) due to neurological impairment (NI). 13C has been used as an alternative tool for measuring the gastric emptying... Introduction: Delayed gastric emptying (DGE) often occurs in patients with gastroesophageal reflux (GER) due to neurological impairment (NI). 13C has been used as an alternative tool for measuring the gastric emptying rates. The aim of this study was to predict gastric emptying in children with GER using 13C-acetate breath test (ABT) by 24-hour pH monitoring. Methods: Nineteen patients were divided into 2 groups: a DGE group with NI (14 patients), and normal-emptying group without NI (5 patients). The liquid test meal consisted of RacolTM (5 ml/kg) mixed with 13C-acetate (50 mg for infants, 100 mg for children, and 150 mg for adolescents). 13CO2 was measured using a gas chromatograph-isotope ratio mass spectrometer. The results are expressed as the % of 13C expired per hour and cumulative 13C excretion over a 3-hour periods including the parameters of half excretion and lag time. Results: The mean half excretion time was 1.762 hour in the DGE group and 1.095 hour in the normal-emptying group (P = 0.0196). The mean lag time was 0.971 hour in the DGE group and 0.666 hour in the normal-emptying group (P = 0.0196). Therefore, DGE was significantly more prevalent in the DGE compared to the normal-emptying group. The percentage of the time when the pH was less than 4 on 24-hour esophageal pH monitoring was 21.6% ± 9.2% in the DGE group and 28.5% ± 11.6% in the normal-emptying group (P = 0.4634). Conclusion: The percentage of time when the pH is less than 4 on 24-hour pH monitoring cannot predict DGE measured by the 13C-ABT in GER. 展开更多
关键词 Delayed Gastric EMPTYING GASTROESOPHAGEAL REFLUX NEUROLOGICAL Impairment 13C-Acetate Breath test 24-Hour pH monitoring
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A Study on Health Monitoring of Structural Damages for Two Stories Model by Using Vibration Test
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作者 Toshikazu Ikemoto Reza Amiraslanzadeh Masakatsu Miyajima 《Open Journal of Civil Engineering》 2014年第4期353-360,共8页
Many structures in Japan were built after the war at a revival term or rapid economic growth. These structures have been reached a life in recent years and it is economically not affordable to conduct repair and recon... Many structures in Japan were built after the war at a revival term or rapid economic growth. These structures have been reached a life in recent years and it is economically not affordable to conduct repair and reconstruct these structures only with a possibility of being damaged. This paper presents an approach to detect the structural damages for two degrees of freedom (2DOF) model. In this study, we conducted Microtremor measurement, free vibration test and vibration test. The 2DOF model was demonstrated the feasibility of using the proposed approach to damage detection of structural member. 展开更多
关键词 HEALTH monitoring STRUCTURAL DAMAGE VIBRATION test MICROTREMOR MEASUREMENTS
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Implementation Method of Non-Intrusive Monitoring Mechanism for Web Services Testing
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作者 Lun Cai Jing-Ling Liu Xi Wang 《Journal of Electronic Science and Technology of China》 2009年第3期207-213,共7页
In web services testing, accessing the interactive contents of measured Services and the information of service condition accurately are the key issues of system design and realization. A non-intrusive solution based ... In web services testing, accessing the interactive contents of measured Services and the information of service condition accurately are the key issues of system design and realization. A non-intrusive solution based on axis2 is presented to overcome the difficulty of the information retrieval in web service testing. It can be plugged in server side or client side freely to test pre-deployed or deployed web services. Moreover, it provides a monitoring interface and the corresponding subscription publication mechanism for users based on web services to support the quality assurance grounded on service-oriented architecture (SOA) application service. 展开更多
关键词 monitoring mechanism service-oriented architecture web services testing
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Operational modal identification of suspension bridge based on structural health monitoring system 被引量:7
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作者 李枝军 李爱群 韩晓林 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期104-107,共4页
An output-only modal identification method by a combination use of the peak-picking method and the cross spectrum methods are presented. Meanwhile, a novel mode shape optimum method of the deck is proposed. The method... An output-only modal identification method by a combination use of the peak-picking method and the cross spectrum methods are presented. Meanwhile, a novel mode shape optimum method of the deck is proposed. The methods are applied to the operational modal identification system of the Runyang Suspension Bridge, which can be used to obtain the modal parameters of the bridge from out-only data sets collected by its structural health monitoring system (SHMS). As an example, the vibration response data of the deck, cable and tower recorded during typhoon Matsa excitation are used to illustrate the program application. Some of the modal frequencies observed from deck vibration responses are also found in the vibration responses of the cable and the tower. The results show that some modal shapes of the deck are strongly coupled with the cable and the tower. By comparing the identification results from the operational modal system with those from field measurements, a good agreement between them is achieved, but some modal frequencies identified from the operational modal identification system (OMIS), such as L1 and L2, obviously decrease compared with those from the field measurements. 展开更多
关键词 suspension bridge operational modal identification structural health monitoring system ambient vibration test
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In-situ monitoring plume,spattering behavior and revealing their relationship with melt flow in laser powder bed fusion of nickel-based superalloy
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作者 You Wang Wei Guo +4 位作者 Yinkai Xie Huaixue Li Caiyou Zeng Ming Xu Hongqiang Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第10期44-58,共15页
Laser powder bed fusion(LPBF)is a highly dynamic and complex physical process,and single-track de-fects tend to accumulate into non-negligible internal defects of parts.The nickel-based superalloy single track was fab... Laser powder bed fusion(LPBF)is a highly dynamic and complex physical process,and single-track de-fects tend to accumulate into non-negligible internal defects of parts.The nickel-based superalloy single track was fabricated by LPBF,and its plume and spattering behavior were monitored in situ and recorded in real time based on image recognition and tracking in this study.The relationship among laser energy density,melt flow,plume and spattering behavior during LPBF was discussed.Volumetric energy density had limitations as a design parameter for LPBF.However,we found that plume and spattering behavior can be used as real-time design parameters for the processing of LPBF parts and implemented the initial velocity statistics for LPBF single-track spattering based on the centroid extraction algorithm.The influ-ence of melt flow evolution paths on the spattering and plume behavior in three different melting modes was revealed,and a shift in plume behavior was found in the overlap region of the additive substrate.This study provides a new method for obtaining statistics of spattering-related physical quantities in the melting mode,which is beneficial for the development of processing methods to mitigate the instability of the LPBF process. 展开更多
关键词 Laser powder bed fusion Plume behavior Spattering behavior in-situ monitoring Ickel-based superalloy
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Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning
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作者 Qiang-Qiang Liu Shu-Ting Liu +2 位作者 Ying-Guang Li Xu Liu Xiao-Zhong Hao 《Advances in Manufacturing》 SCIE EI CAS CSCD 2024年第1期167-176,共10页
Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite parts.Traditional embedded sensor-based technologies have difficulty mon... Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite parts.Traditional embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the part.In this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is proposed.Using the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating patterns.In addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the part.This method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry. 展开更多
关键词 Online monitoring Curing temperature field Deep learning(DL) in-situ heating
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