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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops on-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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Role of macroscopic on-site evaluation of endoscopic ultrasoundguided fine-needle aspiration/biopsy:Results of a multicentric prospective study
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作者 Hussein H Okasha Hiwa A Hussein +24 位作者 Khaled M Ragab Omar Abdallah Fedoua Rouibaa Borahma Mohamed Fahd Ghalim Mahmoud Farouk Mohamed Lasheen Mohamed A Elbasiony Ahmed E Alzamzamy Ahmed El Deeb Hassan Atalla Mahmoud El-Ansary Sahar Mohamed Moaz Elshair Wafaa Khannoussi Mohamed Z Abu-Amer Amine Elmekkaoui Mohammed S Naguib Adil Ait Errami Ahmed El-Meligui Ahmed H El-Habashi Mahmoud G Ameen Dalia Abdelfatah Mona Kaddah Hanane Delsa 《World Journal of Gastrointestinal Endoscopy》 2024年第11期595-606,共12页
BACKGROUND The concept of macroscopic on-site evaluation(MOSE)was introduced in 2015 when the endoscopist observed better diagnostic yield when the macroscopically visible core on MOSE was superior to 4 mm.Recent stud... BACKGROUND The concept of macroscopic on-site evaluation(MOSE)was introduced in 2015 when the endoscopist observed better diagnostic yield when the macroscopically visible core on MOSE was superior to 4 mm.Recent studies suggest that MOSE by the endoscopist may be an excellent alternative to rapid on-site evaluation,and some classi-fications have been published.Few studies have assessed the adequacy of histologic cores in MOSE during endoscopic ultrasound-guided fine-needle aspiration/biopsy(EUS-FNA/FNB).AIM To evaluate the performance of MOSE during EUS-FNA/FNB.METHODS This multicentric prospective study was conducted in 16 centers in 3 countries(Egypt,Iraq,and Morocco)and included 1108 patients with pancreatic,biliary,or gastrointestinal pathology who were referred for EUS examination.We prospectively analyzed the MOSE in 1008 patients with available histopathological reports according to 2 classifications to determine the adequacy of the histological core samples.Data management and analysis were performed using a Statistical Package for Social Sciences(SPSS)version 27.RESULTS A total of 1074 solid lesions were biopsied in 1008 patients with available cytopathological reports.Mean age was 59 years,and 509 patients(50.5%)were male.The mean lesion size was 38 mm.The most frequently utilized needles were FNB-Franseen(74.5%)and 22 G(93.4%),with a median of 2 passes.According to 2 classifications,618 non-bloody cores(61.3%)and 964 good samples(95.6%)were adequate for histological evaluation.The overall diagnostic yield of cytopathology was 95.5%.The cytological examination confirmed the diagnosis of malignancy in 861 patients(85.4%),while 45 samples(4.5%)were inconclusive.Post-procedural adverse events occurred in 33 patients(3.3%).Statistical analysis showed a difference between needle types(P=0.035)with a high sensitivity of FNB(97%).The analysis of the relationship between the MOSE-score and the final diagnosis showed a significant difference between the different scores of the MOSE(P<0.001).CONCLUSION MOSE is a simple method that allows endoscopists to increase needle passes to improve sample quality.There is significantly higher FNB sensitivity and cytopathology diagnostic yield with good MOSE cores. 展开更多
关键词 Macroscopic on-site evaluation Fine-needle aspiration Fine-needle biopsy Endoscopic ultrasound SPECIMEN
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Research on Energy Efficiency Characteristics of Mining Shovel Hoisting and Slewing System Driven by Hydraulic-Electric Hybrid System
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作者 Xiangyu Wang Lei Ge +1 位作者 Yunhua Li Long Quan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期197-211,共15页
Mining shovel is a crucial piece of equipment for high-efficiency production in open-pit mining and stands as one of the largest energy consumption sources in mining.However,substantial energy waste occurs during the ... Mining shovel is a crucial piece of equipment for high-efficiency production in open-pit mining and stands as one of the largest energy consumption sources in mining.However,substantial energy waste occurs during the descent of the hoisting system or the deceleration of the slewing platform.To reduce the energy loss,an innovative hydrau-lic-electric hybrid drive system is proposed,in which a hydraulic pump/motor connected with an accumulator is added to assist the electric motor to drive the hoisting system or slewing platform,recycling kinetic and potential energy.The utilization of the kinetic and potential energy reduces the energy loss and installed power of the min-ing shovel.Meanwhile,the reliability of the mining shovel pure electric drive system also can be increased.In this paper,the hydraulic-electric hybrid driving principle is introduced,a small-scale testbed is set up to verify the feasibil-ity of the system,and a co-simulation model of the proposed system is established to clarify the system operation and energy characteristics.The test and simulation results show that,by adopting the proposed system,compared with the traditional purely electric driving system,the peak power and energy consumption of the hoisting electric motor are reduced by 36.7%and 29.7%,respectively.Similarly,the slewing electric motor experiences a significant decrease in peak power by 86.9%and a reduction in energy consumption by 59.4%.The proposed system expands the application area of the hydraulic electric hybrid drive system and provides a reference for its application in over-sized and super heavy equipment. 展开更多
关键词 Mining shovel hoisting and slewing system Hydraulic-electric hybrid drive Energy saving
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Cheesy material on macroscopic on-site evaluation after endoscopic ultrasound-guided fine-needle biopsy:Don't miss the tuberculosis
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作者 Hanane Delsa Khadija Bellahammou +1 位作者 Hussein Hassan Okasha Fahd Ghalim 《World Journal of Clinical Cases》 SCIE 2023年第10期2181-2188,共8页
Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)is an excellent investigation to diagnose pancreatic lesions and has shown high accuracy for its use in pathologic diagnosis.Recently,macroscopic on-site evaluat... Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)is an excellent investigation to diagnose pancreatic lesions and has shown high accuracy for its use in pathologic diagnosis.Recently,macroscopic on-site evaluation(MOSE)performed by an endoscopist was introduced as an alternative to rapid on-site cytologic evaluation to increase the diagnostic yield of EUS-FNB.The MOSE of the biopsy can estimate the adequacy of the sample directly by the macroscopic evaluation of the core tissue obtained from EUS-FNB.Isolated pancreatic tuberculosis is extremely rare and difficult to diagnose because of its non-specific signs and symptoms.Therefore,this challenging diagnosis is based on endoscopy,imaging,and the bacteriological and histological examination of tissue biopsies.This uncommon presentation of tuberculosis can be revealed as pancreatic mass mimicking cancer.EUS-FNB can be very useful in providing a valuable histopathological diagnosis.A calcified lesion with a cheesy core in MOSE must be suggestive of tuberculosis,leading to the request of the GeneXpert,which can detect Mycobacterium tuberculosis deoxyribonucleic acid and resistance to rifampicin.A decent diagnostic strategy is crucial to prevent unnecessary surgical resection and to supply conservative management with antitubercular therapy. 展开更多
关键词 Pancreatic tuberculosis Endoscopic ultrasound Fine-needle biopsy Macroscopic on-site evaluation Cheesy material GeneXpert
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Rapid on-site evaluation of endoscopic-ultrasound-guided fine-needle aspiration diagnosis of pancreatic masses 被引量:17
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作者 Julio Iglesias-Garcia Jose Lario-Noia +1 位作者 Ihab Abdulkader J Enrique Domínguez-Muoz 《World Journal of Gastroenterology》 SCIE CAS 2014年第28期9451-9457,共7页
Endoscopic ultrasound (EUS) has become an essential tool for the study of pancreatic diseases. Specifically, EUS plays a pivotal role evaluating patients with a known or suspected pancreatic mass. In this setting, dif... Endoscopic ultrasound (EUS) has become an essential tool for the study of pancreatic diseases. Specifically, EUS plays a pivotal role evaluating patients with a known or suspected pancreatic mass. In this setting, differential diagnosis remains a clinical challenge. EUS-guided fine-needle aspiration (FNA) and fine-needle biopsy (FNB) have been proven to be safe and useful tools in this setting. EUS-guided FNA and FNB, by obtaining cytological and/or histological samples, are able to diagnose pancreatic lesions with high sensitivity and specificity. In this context, several methodological features, trying to increase the diagnostic yield of EUS-guided FNA and FNB, have been evaluated. In this review, we focus on the role of rapid on-site evaluation (ROSE). From data reported in the literature, ROSE may increase diagnostic yield of EUS-FNA specimens by 10%-30%, and thus, diagnostic accuracy. However, we should point out that many recent studies have reported adequacy rates of &#x0003e; 90% without ROSE, indicating that, perhaps, at high-volume centers, ROSE may not be indispensable to achieve excellent results. The use of ROSE can be considered important during the learning curve of EUS-FNA, and also in hospital with diagnostic accuracy rates &#x0003c; 90%. 展开更多
关键词 Endoscopic-ultrasound-guided fine-needle aspiration Rapid on-site evaluation Solid pancreatic tumors Diagnostic accuracy
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Theoretical coupling longitudinal-transverse model and experimental verification of transverse vibration of rope for multi-rope friction hoisting system 被引量:4
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作者 Juan Wu Ziming Kou 《International Journal of Coal Science & Technology》 EI 2016年第1期77-84,共8页
Using the mass of time-varying length balance rope focused on the hoisting conveyance, the coupling longi- tudinal-transverse model of mine friction hoist was established by using of the Hamilton's principle. The mod... Using the mass of time-varying length balance rope focused on the hoisting conveyance, the coupling longi- tudinal-transverse model of mine friction hoist was established by using of the Hamilton's principle. The modified Galerkin's method was used to discretize partial differential Eqs. The mine hoisting system was used to the example to analysis the relation between the load, velocity and transverse vibration of rope. The in situ tests were illustrated to evaluate the proposed mathematical model. The results showed that the modeling method can well represent the transverse vibration of rope. 展开更多
关键词 hoisting system VIBRATION ROPE Longitudinal-transverse COUPLING
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Study on the instability of airflow in mine hoisting-shaf 被引量:7
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作者 王海桥 田峰 黄俊歆 《Journal of Coal Science & Engineering(China)》 2007年第1期69-73,共5页
In order to discover the airflow pattern in mine shaft which outfitted with hoist equipment (HE), this paper set up the physical model and anatomized the piston-wind caused by hoist equipment, and researched the flo... In order to discover the airflow pattern in mine shaft which outfitted with hoist equipment (HE), this paper set up the physical model and anatomized the piston-wind caused by hoist equipment, and researched the flow field and velocity field around the hoist equipment during its moving process, and analyzed the airflow around single and couple hoist equipment as well as decisive range of piston effect and additional effect of hoist equipment to ventilation system. Research conclusion indicate that during hoist equipment movement, airflow pattern changes repeatedly because of the influence of pis-ton effect from hoist equipment, and the study of airflow stability in shaft is the foundation for the stability of ventilation in mine. 展开更多
关键词 mine shaft hoist equipment (HE) piston effect ventilation system unsteady flow
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Improved edge lightweight YOLOv4 and its application in on-site power system work 被引量:5
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作者 Kexin Li Liang Qin +3 位作者 Qiang Li Feng Zhao Zhongping Xu Kaipei Liu 《Global Energy Interconnection》 EI CAS CSCD 2022年第2期168-180,共13页
A“cloud-edge-end”collaborative system architecture is adopted for real-time security management of power system on-site work,and mobile edge computing equipment utilizes lightweight intelligent recognition algorithm... A“cloud-edge-end”collaborative system architecture is adopted for real-time security management of power system on-site work,and mobile edge computing equipment utilizes lightweight intelligent recognition algorithms for on-site risk assessment and alert.Owing to its lightweight and fast speed,YOLOv4-Tiny is often deployed on edge computing equipment for real-time video stream detection;however,its accuracy is relatively low.This study proposes an improved YOLOv4-Tiny algorithm based on attention mechanism and optimized training methods,achieving higher accuracy without compromising the speed.Specifically,a convolution block attention module branch is added to the backbone network to enhance the feature extraction capability and an efficient channel attention mechanism is added in the neck network to improve feature utilization.Moreover,three optimized training methods:transfer learning,mosaic data augmentation,and label smoothing are used to improve the training effect of this improved algorithm.Finally,an edge computing equipment experimental platform equipped with an NVIDIA Jetson Xavier NX chip is established and the newly developed algorithm is tested on it.According to the results,the speed of the improved YOLOv4-Tiny algorithm in detecting on-site dress code compliance datasets is 17.25 FPS,and the mean average precision(mAP)is increased from 70.89%to 85.03%. 展开更多
关键词 on-site power system work YOLOv4-Tiny Convolution block attention mechanism Efficient channel attention Optimized training methods.
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Random Forests Algorithm Based Duplicate Detection in On-Site Programming Big Data Environment 被引量:1
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作者 Qianqian Li Meng Li +1 位作者 Lei Guo Zhen Zhang 《Journal of Information Hiding and Privacy Protection》 2020年第4期199-205,共7页
On-site programming big data refers to the massive data generated in the process of software development with the characteristics of real-time,complexity and high-difficulty for processing.Therefore,data cleaning is e... On-site programming big data refers to the massive data generated in the process of software development with the characteristics of real-time,complexity and high-difficulty for processing.Therefore,data cleaning is essential for on-site programming big data.Duplicate data detection is an important step in data cleaning,which can save storage resources and enhance data consistency.Due to the insufficiency in traditional Sorted Neighborhood Method(SNM)and the difficulty of high-dimensional data detection,an optimized algorithm based on random forests with the dynamic and adaptive window size is proposed.The efficiency of the algorithm can be elevated by improving the method of the key-selection,reducing dimension of data set and using an adaptive variable size sliding window.Experimental results show that the improved SNM algorithm exhibits better performance and achieve higher accuracy. 展开更多
关键词 on-site programming big data duplicate record detection random forests adaptive sliding window
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New Explorations of Laboratory and On-site Testing of Broadband Seismographs in China
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作者 XIE Jianbo YANG Dake +6 位作者 LI Xiaojun YUAN Songyong TONG Wanglian MA Jiemei XU Weiwei DING Lisha YE Shishan 《Earthquake Research in China》 CSCD 2019年第1期9-23,共15页
According to different testing purposes, methods and available environmental conditions, the seismograph testing can be divided into laboratory and on-site testing, respectively. The testing of the seismograph's k... According to different testing purposes, methods and available environmental conditions, the seismograph testing can be divided into laboratory and on-site testing, respectively. The testing of the seismograph's key parameters and other concerning technical specifications are well described in guide documents(China Earthquake Administration, 2017). This includes seismometer sensitivity, linearity and clip levels based on the shake table test, as well as the seismometer natural period, damping constant based on electrical calibration(Wang Guangfu,1986; Ple?inger A.,1993) and instrumental self-noise collocation estimation(Holcomb L.G., 1989; Sleeman R. et al., 2006). However, with the development of seismic observation technology, many new requirements for the performance evaluation of seismographs have been put forward, and new testing items and methods have emerged. 展开更多
关键词 BROADBAND seismographs LABORATORY TESTING on-site TESTING
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Dynamical energy equipartition of the Toda model with additional on-site potentials
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作者 张振俊 唐春梅 +1 位作者 康静 童培庆 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第10期107-111,共5页
We study the dynamical energy equipartition properties in the integrable Toda model with additional uniform or disordered on-site energies by extensive numerical simulations. The total energy is initially equidistribu... We study the dynamical energy equipartition properties in the integrable Toda model with additional uniform or disordered on-site energies by extensive numerical simulations. The total energy is initially equidistributed among some of the lowest frequency linear modes. For the Toda model with uniform on-site potentials, the energy spectrum keeps its profile nearly unchanged in a relatively short time scale. On a much longer time scale, the energies of tail modes increase slowly with time. Energy equipartition is far away from being attached in our studied time scale. For the Toda model with disordered on-site potentials, the energy transfers continuously to the high frequency modes and eventually towards energy equipartition. We further perform a systematic study of the equipartition time teq depending on the energy density ε and the nonlinear parameter α in the thermodynamic limit for the Toda model with disordered on-site potentials. We find teq∝ (1/ε)^a(1/α)^b, where b≈ 2a. The values of a and b are increased when increasing the strengths of disordered on-site potentials or decreasing the number of initially excited modes. 展开更多
关键词 energy transport behaviors Toda model uniform or disordered on-site potentials
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Increased Effluent Dosage Effects on On-Site Wastewater Treatment Systems of Differing Architecture Type
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作者 Andrew Gibbons Kristofor R. Brye +3 位作者 Sam Dunn Edward E. Gbur Andrew N. Sharpley Wen Zhang 《Journal of Environmental Protection》 2015年第6期651-670,共20页
Approximately 20% of homes nationwide use an on-site treatment system as a form of household wastewater management. However, approximately 10% to 20% of on-site treatment systems malfunction each year, many of which h... Approximately 20% of homes nationwide use an on-site treatment system as a form of household wastewater management. However, approximately 10% to 20% of on-site treatment systems malfunction each year, many of which have either failed or exceeded the soil’s long-term acceptance rate (LTAR), causing environmental and human health risks. The objective of this field study was to evaluate the effects of soil condition (e.g., wet and dry) and product architecture type [i.e., chamber, gravel-less-pipe (GLP), polystyrene-aggregate, and pipe-and-aggregate] on in-product solution storage and biomat thickness in a profile-limited soil in northwest Arkansas under increased loading rates and to estimate the LTAR for each product. During Phase I of this study (March 13 to October 4, 2013), effluent loading rates were approximately doubled, while rates were approximately quadrupled during Phase II (October 8, 2013 to May 29, 2014), from the maximum allowable loading rate for each product. The pipe-and-tire-chip, 46-cm-wide trench pipe-and-gravel, and the 25-cm diameter GLP products had the greatest (p < 0.001), while the 31-cm-width and the 5.4-m-long chambers had the lowest (p < 0.001) in-product solution storage during wet-soil conditions of Phase I monitoring. The 25-cm diameter GLP product had the greatest (p < 0.001), while the 61-cm-width, 5.4-m-long chamber had the lowest (p < 0.001) in-product solution storage during Phase II. Results of this study indicate that some alternative products may be able to effectively handle effluent loading rates in excess of those currently allowed by the State of Arkansas. Further research will be required to confirm these interpretations. 展开更多
关键词 on-site WASTEWATER Ozark HIGHLANDS Profile-Limited Soil WASTEWATER Treatment
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A rapid on-site calibration method for measuring dynamic envelope curve of high-speed trains
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作者 LIU Chang-jie YANG Du-juan +1 位作者 FU Lu-hua WANG Zhong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第3期205-214,共10页
Dynamic envelope curve is a significant parameter to assess the running safety of high-speed trains.Up to now the method based on binocular stereo vision is the only way available to measure the dynamic envelope curve... Dynamic envelope curve is a significant parameter to assess the running safety of high-speed trains.Up to now the method based on binocular stereo vision is the only way available to measure the dynamic envelope curve of a train,the speed of which is over200km/h.Nevertheless the method has two limitations,one is large field-〇f-view(FO V),the other is calibration time.Hence portable calibration equipment,easy-t〇-build target and rapid calibration algorithm are required to complete the calibration.In this paper,a new rapid on-site calibration method with large FOV based on binocular stereo vision is proposed.To address these issues,a light target has been designed,the rail coordinate system(RCS)is represented by40fixed retroreflective points on the target,and they are utilized to calibrate the parameters of two cameras.In addition,two cameras merely capture a single image of the target simultaneously,and the intrinsic and extrinsic parameters of the cameras can be calculated rapidly.To testify the proposed method,the experiments have been conducted and the results reveal that the accuracy can reach+1mm,which can meet the measurement requirement. 展开更多
关键词 high-speed train dynamic envelope curve on-site calibration field-〇f-view (FOV)
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Research on temperature rise of hoisting machine disk brake
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作者 MA Jun JANG Hai-bo 《Journal of Coal Science & Engineering(China)》 2012年第4期423-427,共5页
A mathematical model and finite element model for analysis of temperature rise of the hoisting machine brake sys- tem was constructed, limit conditions were defined, and the law of temperature rise of brake shoes duri... A mathematical model and finite element model for analysis of temperature rise of the hoisting machine brake sys- tem was constructed, limit conditions were defined, and the law of temperature rise of brake shoes during emergent brake course was analyzed and calculated by using finite element software. By analyzing the calculation results, the law of tempera- ture change of surface of brake disk and shoes during the braking process was found. The law of brake shoes surface tempera- ture distribution and the law of temperature change along with thickness of brake shoes at brake time 0.5 s, 1.0 s and 1.5 s was analyzed. A hoisting machine emergent braking test was carried out. Finally, the author concluded that velocity rebound in the process of hoisting machine emergent brake is due to decreased friction coefficient caused by the temperature rise of the brake shoes surface. 展开更多
关键词 hoisting machine disk brake brake shoe temperature distribution finite element method
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On-Site Calibration Method of Dosimeter Based on X-Ray Source
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作者 Wenhui Lv Huiping Guo +4 位作者 Ning Lv Chenyang Tian Kuo Zhao Xiaotian Wang Yijie Hou 《World Journal of Nuclear Science and Technology》 2017年第2期93-102,共10页
The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nu... The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nuclear facilities there are so many environmental dosimeters installed dispers-edly, because of its huge quantity, widely distributed, and in real-time monitoring state;it will cost lots of manpower and finance if it were tak-en to calibrate on standard laboratory;what’s more it will make the en-vironment out of control. To solve the problem of the measurement ac-curacy of the stationary gamma radiation dosimeter, an on-site calibra-tion method is proposed. The radioactive source is X-ray spectrum, and the dose reference instrument which has been calibrated by the national standard laboratory is a high pressure ionization. On-site calibration is divided into two parts;firstly the energy response experiment of dosim-eter for high and low energy is done in the laboratory, and the energy response curve is obtained combining with Monte Carlo simulation;sec-ondly experiment is carried out in the field of the measuring dosimeter, and the substitution method to calibrate the dosimeter is used;finally the calibration coefficient is gotten through energy curve correction. In order to verify the accuracy of on-site calibration method, the calibrated dosimeter is test in the standard laboratory and the error is 3.4%. The re-sult shows that the on-site calibration method using X-ray is feasible, and it can improves the accuracy of the measurement results of the stationary &gamma;-ray instrument;what’s more important is that it has great reference value for the radiation safety management and radiation environment evaluation. 展开更多
关键词 X RAY SOURCE on-site Calibration Energy Response GAMMA RADIATION DOSIMETER
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Study of Movement Reliability for Hoisting Jack under a Rocket Launcher Vehicle
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作者 LI Ye-nong PENG Shu-hua +1 位作者 ZHANG Li-ping SHI Zhu-kang 《International Journal of Plant Engineering and Management》 2011年第3期157-162,共6页
The transmission mechanism of a jack is required to support the combat vehicle reliably within a very short time. So reliability research is very important because the mechanism completes motions required under the co... The transmission mechanism of a jack is required to support the combat vehicle reliably within a very short time. So reliability research is very important because the mechanism completes motions required under the conditions within limited time. If the transmission mechanism of the jack supports the rocket launcher steadily, it needs to go through several stages as follows : unlocking, starting, operating, braking, stopping, fixing position and locking. The transmission mechanism of the jack is a complicated and single degree of freedom mechanical system; it can be considered an imaginary mechanical model that has an equivalent moment of inertia and equivalent torque. According to the characteristics of each supporting stages, dynamics equations of the mechanism are established. At the stages of starting and operating, a driving moment and resistance moment are dealt with for a Normal distribution. The design principles for movement reliability of completing action are established and the design principles for time reliability of completing action within a limited time are established. Finally, movement reliability of the transmission mechanism of the jack is 0. 9 852, according to our calculation. Reliability of time to complete action is 0. 9 943. 展开更多
关键词 rocket launcher vehicle hoisting jack transmission mechanism MOVEMENT RELIABILITY
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Water hammer in coarse grained solid liquid flows in hydraulic hoisting for ocean mining
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作者 韩文亮 王光谦 +2 位作者 吴保生 刘少军 邹伟生 《中国有色金属学会会刊:英文版》 CSCD 2002年第3期508-513,共6页
The particles of polymetallic nodules in hydraulic hoisting flows that are used for mining in deep sea are rather coarse, therefore their flow velocity is smaller than that of the surrounding water. The characteristic... The particles of polymetallic nodules in hydraulic hoisting flows that are used for mining in deep sea are rather coarse, therefore their flow velocity is smaller than that of the surrounding water. The characteristics of solid liquid flows such as their density, concentration, elastic modulus and resistance were discussed. The wave propagation speed and the continuity and momentum equations of water hammer in coarse grained solid liquid flows were theoretically derived, and a water hammer model for such flows was developed. 展开更多
关键词 水锺 固液两相流 海上采矿 水力提升
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An Experience of On-site PD Testing for Condition Monitoring of an 11 kV PILC Cable Insulation System
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作者 Xiaosheng Peng Chengke Zhou Xiaodi Song 《Journal of Energy and Power Engineering》 2012年第1期140-145,共6页
A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to fur... A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to further diagnose and locate the potential problem of the cable system. This paper presents the experience of the present authors carrying out the cable test. Following a brief introduction to the experiment equipments and physical connections, the paper analyses the data collected from the testing, including PD pulse shape analysis, frequency spectrum analysis and phase resolved PD pattern analysis. Associated with PD propagation direction identification, PD source diagnosis and localisation was made. Four different types of sensors, which were adapted during the testing, are shown to have different frequency bandwidths and performed differently. Aider comparing the parameters of the sensor and the PD signals detected by individual sensor, optimal PD monitoring bandwidth for cable system is suggested. 展开更多
关键词 PD identification on-site testing PILC cable switchgear box insulation defect PD propagation direction sensor.
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CBERS-04A is Hoisting onto a LM-4B Carrier Rocket
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作者 SUN Gongming 《Aerospace China》 2019年第4期2-2,共1页
关键词 CBERS-04A is hoisting onto a LM-4B Carrier Rocket
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基于动态贝叶斯网络的装配式建筑吊装施工安全风险分析 被引量:5
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作者 杨文安 李佳欣 《安全与环境学报》 CAS CSCD 北大核心 2024年第4期1328-1336,共9页
针对装配式建筑吊装施工期间风险影响因素多、不确定性高及风险状态随时间动态变化等问题,提出基于动态贝叶斯网络的装配式建筑吊装施工安全风险动态分析方法。首先,根据装配式建筑吊装施工特点和事故致因理论,从“人、物、环、管”4个... 针对装配式建筑吊装施工期间风险影响因素多、不确定性高及风险状态随时间动态变化等问题,提出基于动态贝叶斯网络的装配式建筑吊装施工安全风险动态分析方法。首先,根据装配式建筑吊装施工特点和事故致因理论,从“人、物、环、管”4个方面建立风险指标体系。其次,引入时间维度建立动态贝叶斯网络模型,利用模糊理论和专家打分法量化网络节点的概率,并结合Leaky Noisy-or Gate扩展模型修正条件概率。最后,利用动态贝叶斯网络的双向推理功能对装配式建筑吊装施工安全风险进行动态风险分析。由实例分析得到某装配式建筑吊装施工安全风险的时序变化曲线,通过反向推理得到导致吊装事故发生的关键风险因素。研究成果可为分析和有效控制装配式建筑吊装施工安全风险提供新思路。 展开更多
关键词 安全工程 装配式建筑 吊装施工 动态贝叶斯网络(DBN) 风险分析
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