This paper presents a technique for Medium Term Load Forecasting (MTLF) using Particle Swarm Optimization (PSO) algorithm based on Least Squares Regression Methods to forecast the electric loads of the Jordanian grid ...This paper presents a technique for Medium Term Load Forecasting (MTLF) using Particle Swarm Optimization (PSO) algorithm based on Least Squares Regression Methods to forecast the electric loads of the Jordanian grid for year of 2015. Linear, quadratic and exponential forecast models have been examined to perform this study and compared with the Auto Regressive (AR) model. MTLF models were influenced by the weather which should be considered when predicting the future peak load demand in terms of months and weeks. The main contribution for this paper is the conduction of MTLF study for Jordan on weekly and monthly basis using real data obtained from National Electric Power Company NEPCO. This study is aimed to develop practical models and algorithm techniques for MTLF to be used by the operators of Jordan power grid. The results are compared with the actual peak load data to attain minimum percentage error. The value of the forecasted weekly and monthly peak loads obtained from these models is examined using Least Square Error (LSE). Actual reported data from NEPCO are used to analyze the performance of the proposed approach and the results are reported and compared with the results obtained from PSO algorithm and AR model.展开更多
Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultura...Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months).展开更多
Medium-term forecasting is an important category of electric load forecasting that covers a time span of up to one year ahead. It suits outage and maintenance planning, as well as load switching operation. We propose ...Medium-term forecasting is an important category of electric load forecasting that covers a time span of up to one year ahead. It suits outage and maintenance planning, as well as load switching operation. We propose a new methodol-ogy that uses hourly daily loads to predict the next year hourly loads, and hence predict the peak loads expected to be reached in the next coming year. The technique is based on implementing multivariable regression on previous year's hourly loads. Three regression models are investigated in this research: the linear, the polynomial, and the exponential power. The proposed models are applied to real loads of the Jordanian power system. Results obtained using the pro-posed methods showed that their performance is close and they outperform results obtained using the widely used ex-ponential regression technique. Moreover, peak load prediction has about 90% accuracy using the proposed method-ology. The methods are generic and simple and can be implemented to hourly loads of any power system. No extra in-formation other than the hourly loads is required.展开更多
This paper introduces the space increased probability of strong earthquakes (SIP)-a new design based on the algorithm CN of time increased probability of strong earthquake (TIP). The authors have done a prediction res...This paper introduces the space increased probability of strong earthquakes (SIP)-a new design based on the algorithm CN of time increased probability of strong earthquake (TIP). The authors have done a prediction research passing in review of eight strong earthquakes with M>6 in the last 20 years in East China. The result shows that six of the eight strong earthquakes were in the space-time domain of the time and space probability of strong earthquake (TSIP) prediction. The prediction accuracy is 75%, the space-time domain rate of the TSIP precaution is 5%, the diagnosed value of R is 0. 70. So the TSIP as a method of medium-term earthquake prediction has good practicality, efficiency and prospects of applying.展开更多
Based on the observations of many years, it has been found that “small earthquake modulation windows” exist inthe situation of some special geological structures, which respond sensitively to the variations of regio...Based on the observations of many years, it has been found that “small earthquake modulation windows” exist inthe situation of some special geological structures, which respond sensitively to the variations of regional stressfields and the activities of earthquake swarms greater than moderate strong magnitude, and can supply some precursory information. More than two “small earthquake modulation windows” can also provide a general orientation of the first main earthquake of a earthquake cluster. Compared with “seismic window” based on frequency itis no doubt that the “modulation-window” has an unique characteristic of applicational significance to mediumterm earthquake prediction with a time scale of two or three years.展开更多
Introduction: Stroke is the leading cause of mortality and physical disability in sub-Saharan Africa. Objective: Determining medium-term and long-term mortality for stroke and identifying associated factors. Method: I...Introduction: Stroke is the leading cause of mortality and physical disability in sub-Saharan Africa. Objective: Determining medium-term and long-term mortality for stroke and identifying associated factors. Method: It consists in a cross-sectional, prospective, descriptive and analytical study that was conducted from April 1 to August 31, 2013 in the Neurology Department of CNHU-HKM in Cotonou. It involved patients who have known stroke for at least 6 months, and were all admitted and discharged later on. The disease survivors were re-contacted and examined again at home or at hospital. Then, the number of deceased was systematically recorded with precision of death time-limit. Results: The overall mortality rate was 29%. Mortality was higher with patients over 70 years with a frequency of 57.1%. The medium-term mortality rate was 25% against 4% for long-term. The average time-limit for death occurrence after the vascular incident was 7 months ± 6.4 months. Prognostic factors of mortality were: the age of the patient (IC95% = 7.73 [1.49 - 39.99], p = 0.015 ), marital status (IC95% = 0.27 [0.08 to 0.94], p = 0.039 ) and the presence of aphasia (IC95% = 5.52 [1.45 to 20.94 ], p = 0.012). Conclusion: Stroke mortality still remains significant, even after the patients have been discharged from hospital. A good psychological family support and efficient aphasia coverage are essential for its reduction.展开更多
Bed on the analysis of each parameter describing seismicity,we think A(b)-value can betterquantitatively describe the feature of the enhancement and quietness of seismicity in this paper. Thedata of moderate or small ...Bed on the analysis of each parameter describing seismicity,we think A(b)-value can betterquantitatively describe the feature of the enhancement and quietness of seismicity in this paper. Thedata of moderate or small earthquakes during 1972～1996 in North China are used in space scanningof A(b)-value. The result shows that 2～3 years before most strong earthquakes there wereObviously anomaly zones of A(b)-value with very good prediction effect. Some problems about themedium-term prediction by using A(b)-value are also discussed.展开更多
To predict the area with frequent seismicity and the future risky region of strong earthquakes on the time scale of one or several years is a very important and urgent problem that needs to be solved.On the basis of a...To predict the area with frequent seismicity and the future risky region of strong earthquakes on the time scale of one or several years is a very important and urgent problem that needs to be solved.On the basis of active fault research,pre-warning active faults that have been active recently will be discussed; then the medium-term risky region of strong earthquakes will be delimited around the pre-warning active faults.This method proves to be effective.展开更多
Introduction: Total hip prostheses are a reliable means of treating hip disorders. It is indicated when pain and reduced mobility of the hip become incompatible with the patient’s daily activities. In low-income coun...Introduction: Total hip prostheses are a reliable means of treating hip disorders. It is indicated when pain and reduced mobility of the hip become incompatible with the patient’s daily activities. In low-income countries, the risk factors for hip disease are numerous, but the means for its management, such as total hip prostheses, are not. The aim of this work was to determine the morbi-mortality of total hip prostheses in the short and medium term in our department and to review the literature. Patients and Method: This was a prospective and descriptive study over a period of 9 years. It involved 50 THPs performed on 45 patients. Patients who had received a THP and were followed up for at least two years were included. We excluded patients who were lost to follow-up. The Moore-type posterolateral minimally invasive approach was used. Complications were investigated from the immediate postoperative period and in the medium term. The final functional results were evaluated according to the Postel Merle d’Aubigné score. Results: We performed 50 THPs out of 750 procedures, i.e. , 6.6%. The indications were: primary coxarthrosis 60%, necrosis of the femoral head 26%, post-infectious balloon hip 4%, and pseudarthrosis of the femoral neck 10%. The average time to the consultation was 2.4 years with extremes of 1 and 5 years. According to the terrain, sickle cell disease represented 18%, tuberculosis 12%. Postoperative complications were lameness 12%, dislocation 6%, suppuration 6%, death 4%, peri-prosthetic fracture 8%, loosening 2%, peri-articular ossification 2%, and paralysis of the external popliteal nerve 2%. Conclusion: Whoever performs a THP is obliged to monitor the patient as long as he/she is alive. Complications are possible at any time and can negatively change the assigned goal and force the surgeon to be expensive and sometimes inconclusive secondary interventions.展开更多
The medium-short term forecast for a certain kinds of main earthquake events might be possible with the time-to-failure method presented by Varnes (1989), Bufe and Varnes (1993), which is to simulate an accelerative r...The medium-short term forecast for a certain kinds of main earthquake events might be possible with the time-to-failure method presented by Varnes (1989), Bufe and Varnes (1993), which is to simulate an accelerative releasing model of precursory earthquake energy. By fitting the observed data with the theoretical formula, a medium-short term forecast technique for the main shock events could be established, by which the location, time and magnitude of the main shock could be determined. The data used in the paper are obtained from the earthquake catalogue recorded by Yunnan Regional Seismological Network with a time coverage of 1965~2002. The statistical analyses for the past 37 years show that the data of M2.5 earthquakes were fairly complete. In the present paper, 30 main shocks occurred in Yunnan region were simulated. For 25 of them, the forecasting time and magnitude from the simulation of precursory sequence are very close to the actual values with the precision of about 0.57 (magnitude unit). Suppose that the last event of the precursory sequence is known, then the time error for the forecasting main shock is about 0.64 year. For the other 5 main shocks, the simulation cannot be made due to the insufficient precursory events for the full determination of energy accelerating curve or disturbance to the energy-release curve. The results in the paper indicate that there is no obviously linear relation in the optimal searching radius for the main shock and the precursory events because Yunnan is an active region with damage earthquakes and moderate and small earthquakes. However, there is a strong correlation between the main shock moment and the coefficient k/m. The optimal fitting range for the forecasting time and magnitude can be further reduced using the relation between the main shock moment lgM0 and the coefficient lgk/m and the value range of the restricting index m, by which the forecast precision of the simulated main shock can be improved. The time-to-failure method is used to fit 30 main shocks in the paper and more than 80% of them have acquired better results, indicating that the method is prospective for its ability to forecast the known main shock sequence. Therefore, the prospect is cheerful to make medium-short term forecast for the forthcoming main shocks by the precursory events.展开更多
In this paper, the process of medium- and short-term prediction (submitted in special cards) of the Artux earthquake (MS=6.9) and the Usurian earthquake (MS=5.8) in Xinjiang area, is introduced. The imminent seismic r...In this paper, the process of medium- and short-term prediction (submitted in special cards) of the Artux earthquake (MS=6.9) and the Usurian earthquake (MS=5.8) in Xinjiang area, is introduced. The imminent seismic risk regions are judged based on long- and medium-term seismic risk regions and annual seismic risk regions determined by national seismologic analysis, combined with large seismic situation analysis. We trace and analyze the seismic situation in large areas, and judge principal risk regions or belts of seismic activity in a year, by integrating the large area’s seismicity with geodetic deformation evolutional characteristics. As much as possible using information, we study synthetically observational information for long-medium- and short-term (time domain) and large-medium -small dimensions (space domain), and approach the forecast region of forthcoming earthquakes from the large to small magnitude. A better effect has been obtained. Some questions about earthquake prediction are discussed.展开更多
Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becomi...Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becoming an important social concern to develop and put to practical use simple and efficient health monitoring systems for existing short and medium span (10 - 30 m) bridges. In this paper, one practical solution to the problem for condition assessment of short and medium span bridges was discussed. A vehicle-based measurement with a public bus as part of a public transit system (called “Bus monitoring system”) has been developed to be capable of detecting damage that may affect the structural safety of a bridge from long term vibration measurement data collected while the vehicle (bus) crossed the target bridges. This paper systematically describes how the system has been developed. The bus monitoring system aims to detect the transition from the damage acceleration period, in which the structural safety of an aged bridge declines sharply, to the deterioration period by continually monitoring the bridge of interest. To evaluate the practicality of the newly developed bus monitoring system, it has been field-tested over a period of about four years by using an in-service fixed-route bus operating on a bus route in the city of Ube, Yamaguchi Prefecture, Japan. The verification results thus obtained are also described in this paper. This study also evaluates the sensitivity of “characteristic deflection”, which is a bridge (health) condition indicator used by the bus monitoring system, in damage detection. Sensitivity of “characteristic deflection” is verified by introducing artificial damage into a bridge that has ended its service life and is awaiting removal. As the results, it will be able to make a rational long-term health monitoring system for existing short and mediumspan bridges, and then the system helps bridge administrators to establish the rational maintenance strategies.展开更多
Discussion plays an important role in the process of cadre education and training. Medium - and long-term training courses can organize students to carry out segmented discussion around a topic, with the goal of outpu...Discussion plays an important role in the process of cadre education and training. Medium - and long-term training courses can organize students to carry out segmented discussion around a topic, with the goal of output, to realize the application of knowledge. This paper introduces the practice and application of segmental discussion in mid - and long-term training courses, providing reference and inspiration for the implementation of high quality cadre education and training.展开更多
Chongqing has been trying out medium and long-term electricity transaction to estimate electricity, this paper from the grid load change, water situation estimation, absorption situation, grid structure analysis of va...Chongqing has been trying out medium and long-term electricity transaction to estimate electricity, this paper from the grid load change, water situation estimation, absorption situation, grid structure analysis of various aspects of analysis, finally get the hydropower plant medium and long-term electricity transaction important decision-making opinions.展开更多
Objective: to analyze the mid-term effect of individualized training of dual tutoring system for newly recruited undergraduate nurses, and provides reference for later training. Methods: 60 newly recruited undergradua...Objective: to analyze the mid-term effect of individualized training of dual tutoring system for newly recruited undergraduate nurses, and provides reference for later training. Methods: 60 newly recruited undergraduate nurses were selected for research, and divided into groups according to time. The control group (January 2017 to December 2018) received routine training, and the observation group (January 2019 to December 2021) received personalized training under the dual tutorial system. Compare the training effect. Results: the scores of training theoretical knowledge (92.4 ± 3.8) and professional skills (91.5 ± 4.5) in the observation group were higher than those in the control group (85.8 ± 4.2) and (87.1 ± 4.0) (t9.382, 7.003, P0.000, 0.000). The scores of cognitive value, social support and communication skills, frustration coping and self reflection in the observation group (37.8 ± 3.5), (23.7 ± 2.6), (24.8 ± 2.3), (24.0 ± 2.5), (12.6 ± 1.8) were higher than those in the control group (33.4 ± 3.2), (21.5 ± 3.1), (22.0 ± 2.7), (21.7 ± 3.1) (10.8 ± 1.4) points (t8.035, 6.978, 7.324, 7.163, 7.323, P0.000, 0.004, 0.000, 0.003, 0.000). The total satisfaction rate of the observation group was 96.7% higher than that of the control group (80.0%) (X24.754, P0.029). The self-efficacy score of the observation group (27.2 ± 3.4) was higher than that of the control group (24.6 ± 4.0) (t4.713, P0.009). Conclusion: the individualized training of dual tutor system in newly recruited undergraduate nurses is beneficial to the improvement of the overall level of nurses, their comprehensive ability and their self-efficacy.展开更多
Heavy rain is a kind of severe weather, often causing floods and serious soil erosion, leading to engineering losses, embankment rupture and crop flooding and other significant economic losses. Especially for some low...Heavy rain is a kind of severe weather, often causing floods and serious soil erosion, leading to engineering losses, embankment rupture and crop flooding and other significant economic losses. Especially for some low-lying terrain areas, rainwater cannot quickly vent caused by farm water and soil moisture being too saturated, so it will cause more geological disasters. This article combines live and forecast data, aiming at the results of the mid-rainstorm forecast in North China during the period of 7.19-2016, and compares with the actual situation of rainstorm. We carry out the mid-term forecast of the rainstorm. The atmosphere is a kind of medium with various fluctuation phenomena, and its physical properties and changes are studied by the analysis of volatility which is an important research method. It is important to improve the accuracy of such severe weather forecasting rainstorms and to take precautionary measures in a timely manner to minimize the losses caused by rainstorms.展开更多
Laboratory experiments were conducted to simulate oil weathering process, a medium to long term weathering process for 210-d, using samples collected from five different oil resources. Based on relative deviation and ...Laboratory experiments were conducted to simulate oil weathering process, a medium to long term weathering process for 210-d, using samples collected from five different oil resources. Based on relative deviation and repeatability limit analysis about indexes of these samples, the results show there had been significant changes in diagnostic ratios among the initial and weathered samples of different oils during this process. Changes of selected n-alkane diagnostic ratios of all oil samples displayed more obviously than diagnostic ratios of terpanes,steranes and PAHs in this process. Almost all selected diagnostic ratios of terpanes, steranes and PAHs can be efficiently used in tracking sources of hydrocarbon pollution, differentiating from the n-alkane diagnostic ratios.In these efficient diagnostic ratios, only four ratios maintained good stability in the weathering processes and are more suitable because their relative deviation（RSD） are lower than 5%.展开更多
A hierarchically 3D structured milled lamellar MoS2/nano-siIicon@carbon hybrid with medium capacity and long-term lifespan is designed by a green and scalable approach using ball milling process and spraydrying/ pyrol...A hierarchically 3D structured milled lamellar MoS2/nano-siIicon@carbon hybrid with medium capacity and long-term lifespan is designed by a green and scalable approach using ball milling process and spraydrying/ pyrolysis routes. The microspheres consist of low-content nano-silicon (20 wt%), milled lamellar M0S2 sheets and porous carbon skeletons. A mixture of silicon nanoparticles and M0S2 flakes serves as an inner core, while porous carbon pyrolyzed from petroleum pitch acts as a protective shell. The particular architecture affords robust mechanical support, abundant buffering space and enhanced electrical conductivity, thus effectively accommodating drastic volume variation during repetitive Li+ intercalation/ extraction. The Si/MoS2@C hybrid delivers a high initial discharge specific capacity of 1257.8 mA hg^-1 and exhibits a reversible capacity of 767.52 m A hg^-1 at a current density 100 mA g'1 after 250 cycles. Most impressively, the electrode depicts a superior long-cycling durability with a discharge capacity of 537.6 mA hg^-1 even after 1200 cycles at a current density of 500 m A g^-1. Meanwhile, the hybrid also shows excellent rate performance such as 388.1 mA h g^-1 even at a large current density of 3000 mA g^-1.展开更多
文摘This paper presents a technique for Medium Term Load Forecasting (MTLF) using Particle Swarm Optimization (PSO) algorithm based on Least Squares Regression Methods to forecast the electric loads of the Jordanian grid for year of 2015. Linear, quadratic and exponential forecast models have been examined to perform this study and compared with the Auto Regressive (AR) model. MTLF models were influenced by the weather which should be considered when predicting the future peak load demand in terms of months and weeks. The main contribution for this paper is the conduction of MTLF study for Jordan on weekly and monthly basis using real data obtained from National Electric Power Company NEPCO. This study is aimed to develop practical models and algorithm techniques for MTLF to be used by the operators of Jordan power grid. The results are compared with the actual peak load data to attain minimum percentage error. The value of the forecasted weekly and monthly peak loads obtained from these models is examined using Least Square Error (LSE). Actual reported data from NEPCO are used to analyze the performance of the proposed approach and the results are reported and compared with the results obtained from PSO algorithm and AR model.
基金This study is contribution No. G199901209 of 973 from the Chinese Basic Research Project and Chinese Postdoctor Found
文摘Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months).
文摘Medium-term forecasting is an important category of electric load forecasting that covers a time span of up to one year ahead. It suits outage and maintenance planning, as well as load switching operation. We propose a new methodol-ogy that uses hourly daily loads to predict the next year hourly loads, and hence predict the peak loads expected to be reached in the next coming year. The technique is based on implementing multivariable regression on previous year's hourly loads. Three regression models are investigated in this research: the linear, the polynomial, and the exponential power. The proposed models are applied to real loads of the Jordanian power system. Results obtained using the pro-posed methods showed that their performance is close and they outperform results obtained using the widely used ex-ponential regression technique. Moreover, peak load prediction has about 90% accuracy using the proposed method-ology. The methods are generic and simple and can be implemented to hourly loads of any power system. No extra in-formation other than the hourly loads is required.
文摘This paper introduces the space increased probability of strong earthquakes (SIP)-a new design based on the algorithm CN of time increased probability of strong earthquake (TIP). The authors have done a prediction research passing in review of eight strong earthquakes with M>6 in the last 20 years in East China. The result shows that six of the eight strong earthquakes were in the space-time domain of the time and space probability of strong earthquake (TSIP) prediction. The prediction accuracy is 75%, the space-time domain rate of the TSIP precaution is 5%, the diagnosed value of R is 0. 70. So the TSIP as a method of medium-term earthquake prediction has good practicality, efficiency and prospects of applying.
文摘Based on the observations of many years, it has been found that “small earthquake modulation windows” exist inthe situation of some special geological structures, which respond sensitively to the variations of regional stressfields and the activities of earthquake swarms greater than moderate strong magnitude, and can supply some precursory information. More than two “small earthquake modulation windows” can also provide a general orientation of the first main earthquake of a earthquake cluster. Compared with “seismic window” based on frequency itis no doubt that the “modulation-window” has an unique characteristic of applicational significance to mediumterm earthquake prediction with a time scale of two or three years.
文摘Introduction: Stroke is the leading cause of mortality and physical disability in sub-Saharan Africa. Objective: Determining medium-term and long-term mortality for stroke and identifying associated factors. Method: It consists in a cross-sectional, prospective, descriptive and analytical study that was conducted from April 1 to August 31, 2013 in the Neurology Department of CNHU-HKM in Cotonou. It involved patients who have known stroke for at least 6 months, and were all admitted and discharged later on. The disease survivors were re-contacted and examined again at home or at hospital. Then, the number of deceased was systematically recorded with precision of death time-limit. Results: The overall mortality rate was 29%. Mortality was higher with patients over 70 years with a frequency of 57.1%. The medium-term mortality rate was 25% against 4% for long-term. The average time-limit for death occurrence after the vascular incident was 7 months ± 6.4 months. Prognostic factors of mortality were: the age of the patient (IC95% = 7.73 [1.49 - 39.99], p = 0.015 ), marital status (IC95% = 0.27 [0.08 to 0.94], p = 0.039 ) and the presence of aphasia (IC95% = 5.52 [1.45 to 20.94 ], p = 0.012). Conclusion: Stroke mortality still remains significant, even after the patients have been discharged from hospital. A good psychological family support and efficient aphasia coverage are essential for its reduction.
基金This project was sponsored by China Seismological Bureau(95-04),China
文摘Bed on the analysis of each parameter describing seismicity,we think A(b)-value can betterquantitatively describe the feature of the enhancement and quietness of seismicity in this paper. Thedata of moderate or small earthquakes during 1972～1996 in North China are used in space scanningof A(b)-value. The result shows that 2～3 years before most strong earthquakes there wereObviously anomaly zones of A(b)-value with very good prediction effect. Some problems about themedium-term prediction by using A(b)-value are also discussed.
文摘To predict the area with frequent seismicity and the future risky region of strong earthquakes on the time scale of one or several years is a very important and urgent problem that needs to be solved.On the basis of active fault research,pre-warning active faults that have been active recently will be discussed; then the medium-term risky region of strong earthquakes will be delimited around the pre-warning active faults.This method proves to be effective.
文摘Introduction: Total hip prostheses are a reliable means of treating hip disorders. It is indicated when pain and reduced mobility of the hip become incompatible with the patient’s daily activities. In low-income countries, the risk factors for hip disease are numerous, but the means for its management, such as total hip prostheses, are not. The aim of this work was to determine the morbi-mortality of total hip prostheses in the short and medium term in our department and to review the literature. Patients and Method: This was a prospective and descriptive study over a period of 9 years. It involved 50 THPs performed on 45 patients. Patients who had received a THP and were followed up for at least two years were included. We excluded patients who were lost to follow-up. The Moore-type posterolateral minimally invasive approach was used. Complications were investigated from the immediate postoperative period and in the medium term. The final functional results were evaluated according to the Postel Merle d’Aubigné score. Results: We performed 50 THPs out of 750 procedures, i.e. , 6.6%. The indications were: primary coxarthrosis 60%, necrosis of the femoral head 26%, post-infectious balloon hip 4%, and pseudarthrosis of the femoral neck 10%. The average time to the consultation was 2.4 years with extremes of 1 and 5 years. According to the terrain, sickle cell disease represented 18%, tuberculosis 12%. Postoperative complications were lameness 12%, dislocation 6%, suppuration 6%, death 4%, peri-prosthetic fracture 8%, loosening 2%, peri-articular ossification 2%, and paralysis of the external popliteal nerve 2%. Conclusion: Whoever performs a THP is obliged to monitor the patient as long as he/she is alive. Complications are possible at any time and can negatively change the assigned goal and force the surgeon to be expensive and sometimes inconclusive secondary interventions.
文摘The medium-short term forecast for a certain kinds of main earthquake events might be possible with the time-to-failure method presented by Varnes (1989), Bufe and Varnes (1993), which is to simulate an accelerative releasing model of precursory earthquake energy. By fitting the observed data with the theoretical formula, a medium-short term forecast technique for the main shock events could be established, by which the location, time and magnitude of the main shock could be determined. The data used in the paper are obtained from the earthquake catalogue recorded by Yunnan Regional Seismological Network with a time coverage of 1965~2002. The statistical analyses for the past 37 years show that the data of M2.5 earthquakes were fairly complete. In the present paper, 30 main shocks occurred in Yunnan region were simulated. For 25 of them, the forecasting time and magnitude from the simulation of precursory sequence are very close to the actual values with the precision of about 0.57 (magnitude unit). Suppose that the last event of the precursory sequence is known, then the time error for the forecasting main shock is about 0.64 year. For the other 5 main shocks, the simulation cannot be made due to the insufficient precursory events for the full determination of energy accelerating curve or disturbance to the energy-release curve. The results in the paper indicate that there is no obviously linear relation in the optimal searching radius for the main shock and the precursory events because Yunnan is an active region with damage earthquakes and moderate and small earthquakes. However, there is a strong correlation between the main shock moment and the coefficient k/m. The optimal fitting range for the forecasting time and magnitude can be further reduced using the relation between the main shock moment lgM0 and the coefficient lgk/m and the value range of the restricting index m, by which the forecast precision of the simulated main shock can be improved. The time-to-failure method is used to fit 30 main shocks in the paper and more than 80% of them have acquired better results, indicating that the method is prospective for its ability to forecast the known main shock sequence. Therefore, the prospect is cheerful to make medium-short term forecast for the forthcoming main shocks by the precursory events.
文摘In this paper, the process of medium- and short-term prediction (submitted in special cards) of the Artux earthquake (MS=6.9) and the Usurian earthquake (MS=5.8) in Xinjiang area, is introduced. The imminent seismic risk regions are judged based on long- and medium-term seismic risk regions and annual seismic risk regions determined by national seismologic analysis, combined with large seismic situation analysis. We trace and analyze the seismic situation in large areas, and judge principal risk regions or belts of seismic activity in a year, by integrating the large area’s seismicity with geodetic deformation evolutional characteristics. As much as possible using information, we study synthetically observational information for long-medium- and short-term (time domain) and large-medium -small dimensions (space domain), and approach the forecast region of forthcoming earthquakes from the large to small magnitude. A better effect has been obtained. Some questions about earthquake prediction are discussed.
文摘Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becoming an important social concern to develop and put to practical use simple and efficient health monitoring systems for existing short and medium span (10 - 30 m) bridges. In this paper, one practical solution to the problem for condition assessment of short and medium span bridges was discussed. A vehicle-based measurement with a public bus as part of a public transit system (called “Bus monitoring system”) has been developed to be capable of detecting damage that may affect the structural safety of a bridge from long term vibration measurement data collected while the vehicle (bus) crossed the target bridges. This paper systematically describes how the system has been developed. The bus monitoring system aims to detect the transition from the damage acceleration period, in which the structural safety of an aged bridge declines sharply, to the deterioration period by continually monitoring the bridge of interest. To evaluate the practicality of the newly developed bus monitoring system, it has been field-tested over a period of about four years by using an in-service fixed-route bus operating on a bus route in the city of Ube, Yamaguchi Prefecture, Japan. The verification results thus obtained are also described in this paper. This study also evaluates the sensitivity of “characteristic deflection”, which is a bridge (health) condition indicator used by the bus monitoring system, in damage detection. Sensitivity of “characteristic deflection” is verified by introducing artificial damage into a bridge that has ended its service life and is awaiting removal. As the results, it will be able to make a rational long-term health monitoring system for existing short and mediumspan bridges, and then the system helps bridge administrators to establish the rational maintenance strategies.
文摘Discussion plays an important role in the process of cadre education and training. Medium - and long-term training courses can organize students to carry out segmented discussion around a topic, with the goal of output, to realize the application of knowledge. This paper introduces the practice and application of segmental discussion in mid - and long-term training courses, providing reference and inspiration for the implementation of high quality cadre education and training.
文摘Chongqing has been trying out medium and long-term electricity transaction to estimate electricity, this paper from the grid load change, water situation estimation, absorption situation, grid structure analysis of various aspects of analysis, finally get the hydropower plant medium and long-term electricity transaction important decision-making opinions.
文摘Objective: to analyze the mid-term effect of individualized training of dual tutoring system for newly recruited undergraduate nurses, and provides reference for later training. Methods: 60 newly recruited undergraduate nurses were selected for research, and divided into groups according to time. The control group (January 2017 to December 2018) received routine training, and the observation group (January 2019 to December 2021) received personalized training under the dual tutorial system. Compare the training effect. Results: the scores of training theoretical knowledge (92.4 ± 3.8) and professional skills (91.5 ± 4.5) in the observation group were higher than those in the control group (85.8 ± 4.2) and (87.1 ± 4.0) (t9.382, 7.003, P0.000, 0.000). The scores of cognitive value, social support and communication skills, frustration coping and self reflection in the observation group (37.8 ± 3.5), (23.7 ± 2.6), (24.8 ± 2.3), (24.0 ± 2.5), (12.6 ± 1.8) were higher than those in the control group (33.4 ± 3.2), (21.5 ± 3.1), (22.0 ± 2.7), (21.7 ± 3.1) (10.8 ± 1.4) points (t8.035, 6.978, 7.324, 7.163, 7.323, P0.000, 0.004, 0.000, 0.003, 0.000). The total satisfaction rate of the observation group was 96.7% higher than that of the control group (80.0%) (X24.754, P0.029). The self-efficacy score of the observation group (27.2 ± 3.4) was higher than that of the control group (24.6 ± 4.0) (t4.713, P0.009). Conclusion: the individualized training of dual tutor system in newly recruited undergraduate nurses is beneficial to the improvement of the overall level of nurses, their comprehensive ability and their self-efficacy.
文摘Heavy rain is a kind of severe weather, often causing floods and serious soil erosion, leading to engineering losses, embankment rupture and crop flooding and other significant economic losses. Especially for some low-lying terrain areas, rainwater cannot quickly vent caused by farm water and soil moisture being too saturated, so it will cause more geological disasters. This article combines live and forecast data, aiming at the results of the mid-rainstorm forecast in North China during the period of 7.19-2016, and compares with the actual situation of rainstorm. We carry out the mid-term forecast of the rainstorm. The atmosphere is a kind of medium with various fluctuation phenomena, and its physical properties and changes are studied by the analysis of volatility which is an important research method. It is important to improve the accuracy of such severe weather forecasting rainstorms and to take precautionary measures in a timely manner to minimize the losses caused by rainstorms.
基金The National Natural Science Foundation of China under contract No.41206089Project of on-site sediment microbial remediation of public area of central Bohai Sea,North China Sea Branch of State Oceanic Administration under contract No.QDZC20150420-002Program of Science and Technology Service Network Initiative,Chinese Academy of Sciences under contract No.KFJ-EW-STS-127
文摘Laboratory experiments were conducted to simulate oil weathering process, a medium to long term weathering process for 210-d, using samples collected from five different oil resources. Based on relative deviation and repeatability limit analysis about indexes of these samples, the results show there had been significant changes in diagnostic ratios among the initial and weathered samples of different oils during this process. Changes of selected n-alkane diagnostic ratios of all oil samples displayed more obviously than diagnostic ratios of terpanes,steranes and PAHs in this process. Almost all selected diagnostic ratios of terpanes, steranes and PAHs can be efficiently used in tracking sources of hydrocarbon pollution, differentiating from the n-alkane diagnostic ratios.In these efficient diagnostic ratios, only four ratios maintained good stability in the weathering processes and are more suitable because their relative deviation（RSD） are lower than 5%.
基金support of the Outstanding Young Scholar Project (8S0256) from South China Normal Universitythe Union Project of the National Natural Science Foundation of China and Guangdong Province (U1601214)+2 种基金the Scientific and Technological Plan of Guangdong Province (2017A040405047)the Key Projects of Guangdong Province Nature Science Foundation (2017B030311013)the Scientific and Technological Plan of Guangzhou City (201607010274)
文摘A hierarchically 3D structured milled lamellar MoS2/nano-siIicon@carbon hybrid with medium capacity and long-term lifespan is designed by a green and scalable approach using ball milling process and spraydrying/ pyrolysis routes. The microspheres consist of low-content nano-silicon (20 wt%), milled lamellar M0S2 sheets and porous carbon skeletons. A mixture of silicon nanoparticles and M0S2 flakes serves as an inner core, while porous carbon pyrolyzed from petroleum pitch acts as a protective shell. The particular architecture affords robust mechanical support, abundant buffering space and enhanced electrical conductivity, thus effectively accommodating drastic volume variation during repetitive Li+ intercalation/ extraction. The Si/MoS2@C hybrid delivers a high initial discharge specific capacity of 1257.8 mA hg^-1 and exhibits a reversible capacity of 767.52 m A hg^-1 at a current density 100 mA g'1 after 250 cycles. Most impressively, the electrode depicts a superior long-cycling durability with a discharge capacity of 537.6 mA hg^-1 even after 1200 cycles at a current density of 500 m A g^-1. Meanwhile, the hybrid also shows excellent rate performance such as 388.1 mA h g^-1 even at a large current density of 3000 mA g^-1.
