Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a cr...Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (ECM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the ECM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_C) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which suggests the necessity of robustness evaluation for the machine learning models and the effectiveness of the defined robustness coefficient. This work hopes to give new insights to the robust diagnosis of high temperature PEM fuel cells and more comprehensive performance evaluation of the data-driven method for diagnostic application.展开更多
Background: In the context of the fight against HIV, a lack of skills in monitoring and evaluating the personnel in charge of activities has been identified at the national level. It was the subject of a priority axis...Background: In the context of the fight against HIV, a lack of skills in monitoring and evaluating the personnel in charge of activities has been identified at the national level. It was the subject of a priority axis of the national plan for monitoring and evaluating the fight against HIV (2006-2010) that was aimed at strengthening the capacities of actors in this area. To increase the critical mass of competent human resources in the short term, the National Institute of Public Health (NIPH) of Côte d’Ivoire organized monitoring and evaluation training sessions for healthcare professionals from 2011 to 2016. Methods: A single case study with multiple levels of analysis was carried out, combining a qualitative survey and a literature review. An evaluation was carried out six months after each training session. In addition, the results of the pre- and post-tests and of the daily and final evaluations that accompanied the various training sessions were used to provide further information. The qualitative data collected were analyzed using INVIVO 15 software. Results: Some 89 health professionals (69% men and 31% women) working at the national level (51% at the central level, including 58% in health programs) and in development partner agencies (37%) participated in this capacity building program. Most participants were senior health managers (56%), data managers (23%), and statisticians and computer scientists (10%). Almost all the trainings were financed by 16 technical and financial partners (85%), mainly the MEASURE Evaluation project (27%). Conclusion: M&E training, despite all its imperfections, has made it possible to identify M&E training needs at the national level and to increase the critical mass of national skills and to have some culture in M&E.展开更多
Geological Hazards Investigation and Evaluation is the core course of Environmental Geological Engineering,aiming to cultivate skilled talents with solid theoretical knowledge and excellent practical skills.At present...Geological Hazards Investigation and Evaluation is the core course of Environmental Geological Engineering,aiming to cultivate skilled talents with solid theoretical knowledge and excellent practical skills.At present,the course faces several issues,including a teaching environment disconnected from real-world work scenarios,course content that deviates from job-related tasks,a lack of digital teaching resources,and reliance on a single teaching method,leading to students’poor feedback from employers.Based on the concept of outcome-based education,the course team of Geological Hazards Investigation and Evaluation establishes a“five-step double-rotation”blended teaching model with the help of a Small Private Online Course platform.The program is designed to improve the teaching environment and expand the digitalized teaching resources in order to improve students’learning motivation,enhance learning effectiveness,and cultivate skillful talents who meet employers’satisfaction.展开更多
The county economy serves as the fundamental unit in China’s economic development and construction.There exists a significant correlation between the quality and level of county economic development and the overall e...The county economy serves as the fundamental unit in China’s economic development and construction.There exists a significant correlation between the quality and level of county economic development and the overall economic construction level of the country.In recent years,China’s economy has experienced rapid growth,contributing to an improved living environment and substantial economic income for its citizens.However,this progress has also brought to light certain issues,such as an unbalanced industrial structure and inefficient resource utilization,leading to problems such as low efficiency and severe environmental pollution.Therefore,it becomes imperative to enhance the statistical monitoring and evaluation of high-quality county economic development.This approach aims to gather insights into the development status of the county economy and provide essential data support for decision-making in county economic development.Consequently,this paper proposes development suggestions for the statistical monitoring and evaluation of high-quality county economic development,serving as a crucial starting point for future initiatives.展开更多
Bridge engineering is an important part of basic engineering in today’s transportation field,and its quality and performance have a vital impact on the improvement and development of modern transportation engineering...Bridge engineering is an important part of basic engineering in today’s transportation field,and its quality and performance have a vital impact on the improvement and development of modern transportation engineering.With the continuous development of transportation engineering,the maintenance and reinforcement of existing bridges are also being given more emphasis.In order to scientifically evaluate the effectiveness of bridge maintenance and reinforcement,this paper analyzes its detection and evaluation,including the significance,key points,and main methods of detection and evaluation.Therefore,this analysis aim to provide some reference for the maintenance and reinforcement and the quality improvement of bridge engineering.展开更多
For screening out salt tolerance germplasm and providing materials for ge- netic research of peanut, based on the indexes including relative germination poten- tial, relative germination rate, relative germination ind...For screening out salt tolerance germplasm and providing materials for ge- netic research of peanut, based on the indexes including relative germination poten- tial, relative germination rate, relative germination index and salt-injury rate, 128 peanut germplasms were selected for salt-tolerant identification and estimation under 2.5% NaCI. We found significant but various depressing levels of germination rate under salt stress among different germplasms, and only 5% of 128 germplasms were highly resistant to salinity. We also found that the relative germination index was a useful evaluation index for salt tolerance besides salt damage rate and rela- tive germination rate. After all, we comprehensively screened out 7 materials (JS011, JS024, JS125, JS491, JS523, JS524 and JS525) as salt tolerance germplasms for further research. Key展开更多
In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HH...In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HHTME), which combines the testabi- lity structure model (TSM) with the testability Bayesian networks model (TBNM), is presented. Firstly, the testability network topo- logy of complex equipment is built by using the hierarchical hybrid testability modeling method. Secondly, the prior conditional prob- ability distribution between network nodes is determined through expert experience. Then the Bayesian method is used to update the conditional probability distribution, according to history test information, virtual simulation information and similar product in- formation. Finally, the learned hierarchical hybrid testability model (HHTM) is used to estimate the testability of equipment. Compared with the results of other modeling methods, the relative deviation of the HHTM is only 0.52%, and the evaluation result is the most accu rate.展开更多
This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log ...This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper.展开更多
The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothi...The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM( Peak High/Full Width at Half Maximum) and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall.展开更多
Spine-related disorders are caused by several factors including (1) spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, (2) spinal nerve/visceral nerve compression by injured periverterb...Spine-related disorders are caused by several factors including (1) spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, (2) spinal nerve/visceral nerve compression by injured periverterbal soft tissue, dislocated perivertebral small joint, and proliferative/degenerative tissue and, (3) secondary damage to the spinal cord, peripheral nerve, vessels and autonomic nerve, which further stimulate nerve root sheath and surround- ing pain-carrying nerve fibers. In many cases, the source of pain cannot be detected by standard image modalities. Particularly in anatomically complex regions like the spine, SPECT/CT can be helpful for some aspects by intro- ducing a metabolical dimension to the classical way of morphology-based diagnostic. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical spine-focused setting.展开更多
Using actual precipitation in Shaoyang of 2018-2020,precipitation forecast of ECMWF model was tested.The results showed that winter accuracy rate was the highest,followed by autumn,and summer accuracy rate was the low...Using actual precipitation in Shaoyang of 2018-2020,precipitation forecast of ECMWF model was tested.The results showed that winter accuracy rate was the highest,followed by autumn,and summer accuracy rate was the lowest.24-h TS scoring results showed that the shorter the cumulative time,the lower the TS.Forecasters had a strong ability to predict summer rainstorms.展开更多
A smart fully mechanized coal mining working face is comprised of various heterogeneous equipment that work together in unknown coal seam environments.The goal is to form a smart operational system with comprehensive ...A smart fully mechanized coal mining working face is comprised of various heterogeneous equipment that work together in unknown coal seam environments.The goal is to form a smart operational system with comprehensive perception,decisionmaking,and control.This involves many work points and complex coupling relationships,indicating it needs to be performed in stages and coordinated to address key problems in all directions and along multiple points.However,there are no existing unifed test or analysis tools.Therefore,this study proposed a virtual test and evaluation method for a fully mechanized mining production system with diferent smart levels.This is based on the concept of“real data processing–virtual scene construction–setting key information points–virtual operation and evaluation.”The actual operational data for a specifc working face geology and equipment were reasonably transformed into a visual virtual scene through a movement relationship model.The virtual operations and mining conditions of the working face were accurately reproduced.Based on the sensor and execution error analyses for diferent smart levels,the input interface for sensing,decision-making,and control was established for each piece of equipment,and an operation evaluation system was constructed.The system comprehensively simulates and tests the key points of sensing decision-making and control with various smart levels.The experimental results showed that the virtual scene constructed based on actual operational data has a high simulation degree.Users can simulate,analyze,and evaluate the overall operations of the smart mining 2.0–4.0 working face by inputting key information.The future direction for the smart development of fully mechanized mining is highlighted.展开更多
This paper describes a simple method for the preparation of L-proline stationary phase bonded to silica gel and characterization of the bonded phase by IR spectrometry, elemental analysis and nitrogen adsorption metho...This paper describes a simple method for the preparation of L-proline stationary phase bonded to silica gel and characterization of the bonded phase by IR spectrometry, elemental analysis and nitrogen adsorption method at low temperature.The enantiomeric resolutions of 3-(2-pyridyl)-3-aminopropionic acid and 2,3-diaminobutanoic acid on the bonded phase were carried out.展开更多
Introduction The use of supercritical fluids such as supercritical CO<sub>2</sub>(scCO<sub>2</sub>) has provided a ’clean’ and effective alternative to traditional methods of protein delive...Introduction The use of supercritical fluids such as supercritical CO<sub>2</sub>(scCO<sub>2</sub>) has provided a ’clean’ and effective alternative to traditional methods of protein delivery systems.Here。展开更多
Meteorological disasters usually exert huge impacts on the development of both human society and the economy. According to statistics from the United Nations International Strategy for Disaster Reduction, the annual m...Meteorological disasters usually exert huge impacts on the development of both human society and the economy. According to statistics from the United Nations International Strategy for Disaster Reduction, the annual mean economic loss caused by meteorological disasters accounts for 3%-6% of the total amount of global GDP. China is a country that has been one of the most severely influenced by natural disasters.展开更多
The 300 msw Simulated Saturation Diving Chamber Complex was designed and built by ourselves. It was completed at the end of 1985. A 300 msw trimixed saturation diving experiment was successfully conducted in the compl...The 300 msw Simulated Saturation Diving Chamber Complex was designed and built by ourselves. It was completed at the end of 1985. A 300 msw trimixed saturation diving experiment was successfully conducted in the complex by Chinese Underwater Technology Institute(CUTI) from May 22 to June 12 of 1987. During the experiment, 4 divers habitated in the complex for 20 days, and they performed 16 person-time excursion dives and 8 other tests. The result of the experiment indicates that the complex is well designed, suitably configurated, wholly integrated and steadily run, as well as of low leakage. The main functions of the complex have approached to those of the same kind in the world. The complex can be used as a basic facility for serving the nation's saturation diving technology, underwater operation, personnel training, etc.展开更多
A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measureme...A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measurement is performed by placing the two concentric masses of very different momenta in a vacuum drop capsule which is falling freely in the Earth's gravitational field. A nonzero output of the differential aeeelerometer is an indication of possible violation of new equivalence principle (NEP). We present the conceptual design of a modified free-fall NEP experiment which can be performed at the Belting drop tower. Design and evaluation of the differential accelerometer with a hybrid electrostatic/magnetic suspension system are presented to accommodate for operation on ground and drop-tower tests. Details specific to the measurement uncertainty are discussed to yield an NEP test accuracy of 7.2×10^-9.展开更多
[Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi'an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents...[Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi'an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents, the investigation about the level of indoor radon in one district of Xi'an was developed. Based on the proper monitoring scheme, some typical living rooms were sampled. Through the measurement result, the effects of different factors on radon concentration were obtained. Finally, the radon concentration was transferred into the effective dose per year of local residents. [ Result] Indoor radon concentration in the district was during 49.680 -128.856 Bq/m3, and average concentration in each building was within 100 Bq/m3, which belonged to normal range. When sunny day became rainy day, radon concentration firstly had a rise trend. If continuous rainy weather appeared, indoor radon concentration gradually declined. When other conditions were same, indoor radon concentration under window closing was significantly higher than that under window opening. Indoor radon concentration had a decline trend from 13:00 to 20:00 and a rise trend from 01:00 to 06:00. Condusion The district belonged to radon safety house. To protect residents' health to the maximum extent, according to transfer change rule of the radon, window should be opened to ventilate in the morning when radon concentration was higher.展开更多
L3414 mechanized mining working face (No.14 coal seam) of Lingxin Mine is under the Xitian River.The mining disturbed zone where rock properties and conditions have been changed due to mining, the safety and environme...L3414 mechanized mining working face (No.14 coal seam) of Lingxin Mine is under the Xitian River.The mining disturbed zone where rock properties and conditions have been changed due to mining, the safety and environmental protection were con- cemed greatly. Based on engineering geological environment of L3414 working face and mining factors, the color bore-bole TV inspecting, leakage of drilling fluid monitoring, simulation experiment, numerical computing, in-situ ground stress measurement and subsidence measurement, etal, these programs contribute to the formation of a scientific basis for control water safe mining and normal mining or environmental protection in the condition of existing fully-mechanized mining.展开更多
In order to analyze the sources of merger and acquisition(M & A)information,and the relationship between the M & A information and the M & A corporation management bureau,the searching and evaluation proce...In order to analyze the sources of merger and acquisition(M & A)information,and the relationship between the M & A information and the M & A corporation management bureau,the searching and evaluation procedure of M & A target was discussed.The standard modes and procedures of finding the sources of the M & A target,examination of the M & A information,depicting on the future of M & A,and evaluation of the M & A target,were brought forward.展开更多
基金supported by the Chinese Scholarship Council(Nos.202208320055 and 202108320111)the support from the energy department of Aalborg University was acknowledged.
文摘Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (ECM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the ECM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_C) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which suggests the necessity of robustness evaluation for the machine learning models and the effectiveness of the defined robustness coefficient. This work hopes to give new insights to the robust diagnosis of high temperature PEM fuel cells and more comprehensive performance evaluation of the data-driven method for diagnostic application.
文摘Background: In the context of the fight against HIV, a lack of skills in monitoring and evaluating the personnel in charge of activities has been identified at the national level. It was the subject of a priority axis of the national plan for monitoring and evaluating the fight against HIV (2006-2010) that was aimed at strengthening the capacities of actors in this area. To increase the critical mass of competent human resources in the short term, the National Institute of Public Health (NIPH) of Côte d’Ivoire organized monitoring and evaluation training sessions for healthcare professionals from 2011 to 2016. Methods: A single case study with multiple levels of analysis was carried out, combining a qualitative survey and a literature review. An evaluation was carried out six months after each training session. In addition, the results of the pre- and post-tests and of the daily and final evaluations that accompanied the various training sessions were used to provide further information. The qualitative data collected were analyzed using INVIVO 15 software. Results: Some 89 health professionals (69% men and 31% women) working at the national level (51% at the central level, including 58% in health programs) and in development partner agencies (37%) participated in this capacity building program. Most participants were senior health managers (56%), data managers (23%), and statisticians and computer scientists (10%). Almost all the trainings were financed by 16 technical and financial partners (85%), mainly the MEASURE Evaluation project (27%). Conclusion: M&E training, despite all its imperfections, has made it possible to identify M&E training needs at the national level and to increase the critical mass of national skills and to have some culture in M&E.
基金Scientific Research Fund of Hunan Provincial Education Department Excellent Youth Project(23B0953)Hunan Province Vocational College Education and Teaching Reform Research Project(ZJGB2022427)。
文摘Geological Hazards Investigation and Evaluation is the core course of Environmental Geological Engineering,aiming to cultivate skilled talents with solid theoretical knowledge and excellent practical skills.At present,the course faces several issues,including a teaching environment disconnected from real-world work scenarios,course content that deviates from job-related tasks,a lack of digital teaching resources,and reliance on a single teaching method,leading to students’poor feedback from employers.Based on the concept of outcome-based education,the course team of Geological Hazards Investigation and Evaluation establishes a“five-step double-rotation”blended teaching model with the help of a Small Private Online Course platform.The program is designed to improve the teaching environment and expand the digitalized teaching resources in order to improve students’learning motivation,enhance learning effectiveness,and cultivate skillful talents who meet employers’satisfaction.
文摘The county economy serves as the fundamental unit in China’s economic development and construction.There exists a significant correlation between the quality and level of county economic development and the overall economic construction level of the country.In recent years,China’s economy has experienced rapid growth,contributing to an improved living environment and substantial economic income for its citizens.However,this progress has also brought to light certain issues,such as an unbalanced industrial structure and inefficient resource utilization,leading to problems such as low efficiency and severe environmental pollution.Therefore,it becomes imperative to enhance the statistical monitoring and evaluation of high-quality county economic development.This approach aims to gather insights into the development status of the county economy and provide essential data support for decision-making in county economic development.Consequently,this paper proposes development suggestions for the statistical monitoring and evaluation of high-quality county economic development,serving as a crucial starting point for future initiatives.
文摘Bridge engineering is an important part of basic engineering in today’s transportation field,and its quality and performance have a vital impact on the improvement and development of modern transportation engineering.With the continuous development of transportation engineering,the maintenance and reinforcement of existing bridges are also being given more emphasis.In order to scientifically evaluate the effectiveness of bridge maintenance and reinforcement,this paper analyzes its detection and evaluation,including the significance,key points,and main methods of detection and evaluation.Therefore,this analysis aim to provide some reference for the maintenance and reinforcement and the quality improvement of bridge engineering.
基金Supported by National Peanut Industry Technology System"Nanjing Comprehensive Experimental Station"(CARS-14)the Fund of Independent Innovation of Agricultural Science and Technology in Jiangsu Province"On the Collection,Identification and Shared Service of Germplasm Resources of Main Field Crops"[CX(14)2001]~~
文摘For screening out salt tolerance germplasm and providing materials for ge- netic research of peanut, based on the indexes including relative germination poten- tial, relative germination rate, relative germination index and salt-injury rate, 128 peanut germplasms were selected for salt-tolerant identification and estimation under 2.5% NaCI. We found significant but various depressing levels of germination rate under salt stress among different germplasms, and only 5% of 128 germplasms were highly resistant to salinity. We also found that the relative germination index was a useful evaluation index for salt tolerance besides salt damage rate and rela- tive germination rate. After all, we comprehensively screened out 7 materials (JS011, JS024, JS125, JS491, JS523, JS524 and JS525) as salt tolerance germplasms for further research. Key
基金supported by the National Defense Pre-research Foundation of China(51327030104)
文摘In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HHTME), which combines the testabi- lity structure model (TSM) with the testability Bayesian networks model (TBNM), is presented. Firstly, the testability network topo- logy of complex equipment is built by using the hierarchical hybrid testability modeling method. Secondly, the prior conditional prob- ability distribution between network nodes is determined through expert experience. Then the Bayesian method is used to update the conditional probability distribution, according to history test information, virtual simulation information and similar product in- formation. Finally, the learned hierarchical hybrid testability model (HHTM) is used to estimate the testability of equipment. Compared with the results of other modeling methods, the relative deviation of the HHTM is only 0.52%, and the evaluation result is the most accu rate.
基金Supported by CNPC Innovation Foundation,Research Projects of PetroChina,Xinjiang and Tarim Oil Companies
文摘This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper.
基金Sponsored by the Natural Science Fundation of Jiangxi Province(Grant No.20114BAB211026 and 20122BAB201028)the Open Science Fund from Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense,East China Institute of Technology(Grant No.2010RGET11)
文摘The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM( Peak High/Full Width at Half Maximum) and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall.
文摘Spine-related disorders are caused by several factors including (1) spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, (2) spinal nerve/visceral nerve compression by injured periverterbal soft tissue, dislocated perivertebral small joint, and proliferative/degenerative tissue and, (3) secondary damage to the spinal cord, peripheral nerve, vessels and autonomic nerve, which further stimulate nerve root sheath and surround- ing pain-carrying nerve fibers. In many cases, the source of pain cannot be detected by standard image modalities. Particularly in anatomically complex regions like the spine, SPECT/CT can be helpful for some aspects by intro- ducing a metabolical dimension to the classical way of morphology-based diagnostic. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical spine-focused setting.
文摘Using actual precipitation in Shaoyang of 2018-2020,precipitation forecast of ECMWF model was tested.The results showed that winter accuracy rate was the highest,followed by autumn,and summer accuracy rate was the lowest.24-h TS scoring results showed that the shorter the cumulative time,the lower the TS.Forecasters had a strong ability to predict summer rainstorms.
基金Funding National Natural Science Foundation of China,52004174Major Science and Technology Projects in Shanxi Province,202101020101021+2 种基金Fund for Shanxi“1331”ProjectKey Project of the Chinese Society of Academic Degrees and Graduate Education,2020ZDA12Natural Science Foundation of Shanxi Province,201901D211022.
文摘A smart fully mechanized coal mining working face is comprised of various heterogeneous equipment that work together in unknown coal seam environments.The goal is to form a smart operational system with comprehensive perception,decisionmaking,and control.This involves many work points and complex coupling relationships,indicating it needs to be performed in stages and coordinated to address key problems in all directions and along multiple points.However,there are no existing unifed test or analysis tools.Therefore,this study proposed a virtual test and evaluation method for a fully mechanized mining production system with diferent smart levels.This is based on the concept of“real data processing–virtual scene construction–setting key information points–virtual operation and evaluation.”The actual operational data for a specifc working face geology and equipment were reasonably transformed into a visual virtual scene through a movement relationship model.The virtual operations and mining conditions of the working face were accurately reproduced.Based on the sensor and execution error analyses for diferent smart levels,the input interface for sensing,decision-making,and control was established for each piece of equipment,and an operation evaluation system was constructed.The system comprehensively simulates and tests the key points of sensing decision-making and control with various smart levels.The experimental results showed that the virtual scene constructed based on actual operational data has a high simulation degree.Users can simulate,analyze,and evaluate the overall operations of the smart mining 2.0–4.0 working face by inputting key information.The future direction for the smart development of fully mechanized mining is highlighted.
文摘This paper describes a simple method for the preparation of L-proline stationary phase bonded to silica gel and characterization of the bonded phase by IR spectrometry, elemental analysis and nitrogen adsorption method at low temperature.The enantiomeric resolutions of 3-(2-pyridyl)-3-aminopropionic acid and 2,3-diaminobutanoic acid on the bonded phase were carried out.
文摘Introduction The use of supercritical fluids such as supercritical CO<sub>2</sub>(scCO<sub>2</sub>) has provided a ’clean’ and effective alternative to traditional methods of protein delivery systems.Here。
文摘Meteorological disasters usually exert huge impacts on the development of both human society and the economy. According to statistics from the United Nations International Strategy for Disaster Reduction, the annual mean economic loss caused by meteorological disasters accounts for 3%-6% of the total amount of global GDP. China is a country that has been one of the most severely influenced by natural disasters.
文摘The 300 msw Simulated Saturation Diving Chamber Complex was designed and built by ourselves. It was completed at the end of 1985. A 300 msw trimixed saturation diving experiment was successfully conducted in the complex by Chinese Underwater Technology Institute(CUTI) from May 22 to June 12 of 1987. During the experiment, 4 divers habitated in the complex for 20 days, and they performed 16 person-time excursion dives and 8 other tests. The result of the experiment indicates that the complex is well designed, suitably configurated, wholly integrated and steadily run, as well as of low leakage. The main functions of the complex have approached to those of the same kind in the world. The complex can be used as a basic facility for serving the nation's saturation diving technology, underwater operation, personnel training, etc.
基金Supported by the National Natural Science Foundation of China under Grant Nos 91436107 and 61374207
文摘A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measurement is performed by placing the two concentric masses of very different momenta in a vacuum drop capsule which is falling freely in the Earth's gravitational field. A nonzero output of the differential aeeelerometer is an indication of possible violation of new equivalence principle (NEP). We present the conceptual design of a modified free-fall NEP experiment which can be performed at the Belting drop tower. Design and evaluation of the differential accelerometer with a hybrid electrostatic/magnetic suspension system are presented to accommodate for operation on ground and drop-tower tests. Details specific to the measurement uncertainty are discussed to yield an NEP test accuracy of 7.2×10^-9.
文摘[Objective] The research aimed to monitor and evaluate indoor radon concentration in one district of Xi'an City. r Method] In order to master the effective dose per year caused by natural radiation to local residents, the investigation about the level of indoor radon in one district of Xi'an was developed. Based on the proper monitoring scheme, some typical living rooms were sampled. Through the measurement result, the effects of different factors on radon concentration were obtained. Finally, the radon concentration was transferred into the effective dose per year of local residents. [ Result] Indoor radon concentration in the district was during 49.680 -128.856 Bq/m3, and average concentration in each building was within 100 Bq/m3, which belonged to normal range. When sunny day became rainy day, radon concentration firstly had a rise trend. If continuous rainy weather appeared, indoor radon concentration gradually declined. When other conditions were same, indoor radon concentration under window closing was significantly higher than that under window opening. Indoor radon concentration had a decline trend from 13:00 to 20:00 and a rise trend from 01:00 to 06:00. Condusion The district belonged to radon safety house. To protect residents' health to the maximum extent, according to transfer change rule of the radon, window should be opened to ventilate in the morning when radon concentration was higher.
基金Supported by National Science Foundation(10402033) Ministry of Education Key Lab.of West Mining and Hazard Control Key Research Founda-tion(04JS19) and Shaanxi Province Natural Science (2003E213)
文摘L3414 mechanized mining working face (No.14 coal seam) of Lingxin Mine is under the Xitian River.The mining disturbed zone where rock properties and conditions have been changed due to mining, the safety and environmental protection were con- cemed greatly. Based on engineering geological environment of L3414 working face and mining factors, the color bore-bole TV inspecting, leakage of drilling fluid monitoring, simulation experiment, numerical computing, in-situ ground stress measurement and subsidence measurement, etal, these programs contribute to the formation of a scientific basis for control water safe mining and normal mining or environmental protection in the condition of existing fully-mechanized mining.
文摘In order to analyze the sources of merger and acquisition(M & A)information,and the relationship between the M & A information and the M & A corporation management bureau,the searching and evaluation procedure of M & A target was discussed.The standard modes and procedures of finding the sources of the M & A target,examination of the M & A information,depicting on the future of M & A,and evaluation of the M & A target,were brought forward.