What the newly established mediation body in China’s Hong Kong means for Africa In a world fraying under geopoliti-cal tensions,legal asymmetry,and fragmented global governance,the launch of the International Organis...What the newly established mediation body in China’s Hong Kong means for Africa In a world fraying under geopoliti-cal tensions,legal asymmetry,and fragmented global governance,the launch of the International Organisation for Mediation(IOMed)in China’s Hong Kong on 30 May is much more than a diplomatic novelty.It is a strategic recalibration of how the Global South,particularly African nations,might resolve disputes without surrendering sovereignty or dignity.展开更多
Hi, everyone! I'd like to tell you something about my dream home. It is in a quiet place far away from the city.It's a big house with two floors. On the ground floor, there is a bright kitchen and a dining roo...Hi, everyone! I'd like to tell you something about my dream home. It is in a quiet place far away from the city.It's a big house with two floors. On the ground floor, there is a bright kitchen and a dining room. We usually have nice meal(1) there. On the first floor, there are three bedrooms and a study. It's really nice to have a bedroom of my own.展开更多
Owen McCafferty’s Quietly(2012),a two-hander set in an Irish pub,explores how the Troubles continue to shape everyday life in Northern Ireland-an aspect often overlooked in official narratives that celebrate the succ...Owen McCafferty’s Quietly(2012),a two-hander set in an Irish pub,explores how the Troubles continue to shape everyday life in Northern Ireland-an aspect often overlooked in official narratives that celebrate the success of the peace process.The presence of an immigrant character and modern communication devices in the traditional Irish pub setting signifies a new phase of Northern Irish society following the signing of the Good Friday Agreement.However,the tense and fragmented conversation between the protagonists,along with their sense of disorientation,reveals the persistence of sectarian divisions and the paralysis of everyday life,which,in turn,reinforce narrow conceptions of identity and lead to the ongoing cycle of violence.By bringing the two protagonists together to confront their past and jointly recount the most devastating day of their lives under the witness of a third party,McCafferty presents the possibility of transcending decades of division at the everyday level,suggesting that true peace requires not only political agreements but also open dialogue between opposing sides and a renewal of values through the enrichment of individual lived experiences.展开更多
Rock subjected to freeze-thaw(F-T)cycles may experience alterations in structural integrity and potentially impact its strength.This study investigates the effects of F-T cycles on granite by analyzing the acoustic em...Rock subjected to freeze-thaw(F-T)cycles may experience alterations in structural integrity and potentially impact its strength.This study investigates the effects of F-T cycles on granite by analyzing the acoustic emission(AE)signals recorded during uniaxial compression tests,characterizing the damage responses of the granite influenced by repeated F-T cycles.The results indicate significant reductions in uniaxial compression strength(UCS)and P-wave velocity as the number of F-T cycles increases.AE analysis reveals progressive damage accumulation,characterized by distinct stages of microcrack development.A parameter,AE energy intensity,is introduced to describe the failure process,showing that the typical AE quiet period in the failure stage is absent in granite pretreated with F-T cycles.Using the superlet transform method,AE frequency and amplitude are analyzed,revealing amplitude evolutions across three frequency domains.The results show that decreasing portions of signals in the highfrequency domain for granite are influenced by F-T cycles.These findings enhance understanding of rock degradation under F-T cycles,offering valuable implications for rock engineering in cold regions.展开更多
Acoustic emission （AE） technique is a useful tool for investigating rock damage mechanism, and is used to study the temporal-spatial evolution process of microcracks during the similar pillar material experiment. A ...Acoustic emission （AE） technique is a useful tool for investigating rock damage mechanism, and is used to study the temporal-spatial evolution process of microcracks during the similar pillar material experiment. A combined AE location algorithm was developed based on the Least square algorithm and Geiger location algorithm. The pencil break test results show that the location precision can meet the demand of microcrack monitoring. The 3D location of AE events can directly reflect the process of initiation, propagation and evolutionary of microcracks. During the loading process, stress is much likely concentrated on the area between pillar and roof of the specimen, where belongs to danger zone of macroscopic failure. When rock reaches its plastic deformation stage, AE events begin to decrease, which indicates that AE quiet period can be seen as precursor characteristic of rock failure.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
A high-performance vibration isolation platform （VIP） has been developed for a cluster of control moment gyroscopes （CMGs）. CMGs have long been used for satellite attitude control. In this paper, the influence of ...A high-performance vibration isolation platform （VIP） has been developed for a cluster of control moment gyroscopes （CMGs）. CMGs have long been used for satellite attitude control. In this paper, the influence of flexible solar arrays on a passive multi-strut VIP of CMGs for a satellite is analyzed. The reasonable parameters design of flexi- ble solar arrays is discussed. Firstly, the dynamic model of the integrated satellite with flexible solar arrays, the VIP and CMGs is conducted by Newton-Euler method. Then based on reasonable assumptions, the transmissibility matrix of the VIP is derived. Secondly, the influences of the flexible solar arrays on both the performance of the VIP and the stability of closed-loop control systems are analyzed in detail. The parameter design limitation of these solar arrays is discussed. At last, by selecting reasonable parameters for both the VIP and flexible solar arrays, the attitude stabilization performance with vibration isolation system is predicted via simulation.展开更多
Efcient and accurate monitoring and early warning of coal dynamic disaster and other disasters can provide guarantee for the efcient operation of mine transportation system.However,the traditional threshold early warn...Efcient and accurate monitoring and early warning of coal dynamic disaster and other disasters can provide guarantee for the efcient operation of mine transportation system.However,the traditional threshold early warning method often fails to warning some accidents.To address above issues,a new early warning method was proposed based on"quiet period"phenomenon of AE and EMR during fracture.It is found that,a"quiet period"of AE and EMR was present before the load reaches the peak stress,which could be used as one of the precursors to warn the imminent failure of coal and rock specimens.MS and AE signals increased abnormally followed by the phenomenon of"quiet period"before the occurrence of coal dynamic disaster on site,and the decrease of MS events in the"quiet period"is about 57%–88%compared with that in previous abnormal increase stage.During the damage evolution of coal and rock,"quiet period"phenomenon usually occurred at 85%–90%of the peak stress,where the slope of damage parameter curve is almost zero.The"quiet period"of the AE-EMR signals and the low change rate of damage parameter before failure provide a theoretical foundation for the coal dynamic disaster warning based on the"quiet period"precursor found in MS-AE-EMR monitoring system.These fndings will help reduce the number of under-reported events and improve early warning accuracy.展开更多
There is a growing body of evidence that interest rate spreads in Africa are higher for big banks compared to small banks.One concern is that big banks might be using their market power to charge higher lending rates ...There is a growing body of evidence that interest rate spreads in Africa are higher for big banks compared to small banks.One concern is that big banks might be using their market power to charge higher lending rates as they become larger,more efficient,and unchallenged.In contrast,several studies found that when bank size increases beyond certain thresholds,diseconomies of scale are introduced that lead to inefficiency.In that case,we also would expect to see widened interest margins.This study examines the connection between bank size and efficiency to understand whether that relationship is influenced by exploitation of market power or economies of scale.Using a panel of 162 African banks for 2001–2011,we analyzed the empirical data using instrumental variables and fixed effects regressions,with overlapping and non-overlapping thresholds for bank size.We found two key results.First,bank size increases bank interest rate margins with an inverted U-shaped nexus.Second,market power and economies of scale do not increase or decrease the interest rate margins significantly.The main policy implication is that interest rate margins cannot be elucidated by either market power or economies of scale.Other implications are discussed.展开更多
Mr Michael Dobbs’ article The ABCs of the U.S.A.: America Seen with European Eyes shows the readers 26 points about the American culture. My teaching of it helps grow in me a strong inclination to give a talk abo...Mr Michael Dobbs’ article The ABCs of the U.S.A.: America Seen with European Eyes shows the readers 26 points about the American culture. My teaching of it helps grow in me a strong inclination to give a talk about the following three aspects: a. The American individualism; b. Its quiet surroundings; c. The American people’s attitude toward work. My impression of them has helped me in my understanding of the American culture and its language, so I hope my paper will produce the similar effect on other English learners.展开更多
This study deals with Peak of electron density in F2-layer sensibility scale during quiet time on solar minimum. Peaks of electron density in F2-layer (NmF2) values at the quietest days are compared to those carried o...This study deals with Peak of electron density in F2-layer sensibility scale during quiet time on solar minimum. Peaks of electron density in F2-layer (NmF2) values at the quietest days are compared to those carried out from the two nearest days (previous and following of quietest day). The study uses International Reference Ionosphere (IRI) for ionosphere modeling. The located station is Ouagadougou, in West Africa. Solar minimum of phase 22 is considered in this study. Using three core principles of ionosphere modeling under IRI running conditions, the study enables to carry out Peak of electron density in F2-layer values during the quietest days of the characteristic months for the four different seasons. These parameters are compared to those of the previous and the following of the quietest days (the day before and following each quietest selected day) at the same hour. The knowledge of NmF2 values at the quietest days and at the two nearest days enables to calculate the relative error that can be made on this parameter. This calculation highlights insignificant relative errors. This means that NmF2 values at the two nearest days of each quietest day on solar minimum can be used for simulating the quietest days’ behavior. NmF2 values obtained by running IRI model have good correlation with those carried out by Thermosphere-Ionosphere-Electrodynamics-General Circulation Model (TIEGCM).展开更多
The present study analyzed changes in the biochemical metabolites N-acetyl aspartate, choline, and creatine in a simple concussion rabbit model following quiet rest, hyperbaric oxygen therapy, or interference stimulat...The present study analyzed changes in the biochemical metabolites N-acetyl aspartate, choline, and creatine in a simple concussion rabbit model following quiet rest, hyperbaric oxygen therapy, or interference stimulation through the use of hydrogen proton magnetic resonance spectroscopy detection. Experimental findings showed that brain N-acetyl aspartate and choline peak values significantly decreased, while creatine peak values significantly increased following simple concussion. Following treatments, N-acetyl aspartate and choline peaks returned to normal levels in the quiet rest and hyperbaric oxygen therapy groups, but no changes were observed in the interference stimulation group. Results demonstrated abnormal changes in the brain biochemical metabolism environment following simple concussion. Quiet rest was shown to play an important role in restoration of biochemical metabolism following simple concussion.展开更多
In this paper we simulate the repeated occurrence of strong earthquakes along a strike-slip fault by using a finite element model. The fault valve mechanism is included in the model in order to take into account the e...In this paper we simulate the repeated occurrence of strong earthquakes along a strike-slip fault by using a finite element model. The fault valve mechanism is included in the model in order to take into account the effeCt of POre fluid pressure variation. Five parameters are used to characterize the rheology of the fault, POre pressure variation, and fracture criteria. By Systematically varying these parameters and calculating a large number of models we carried out a preliminary investigation on the alternatively quiet and active periods of seismicity and their relation to model Parameters and loading conditions. Under the action of a constant-rate boundary movement, in the case of intermediate stress and pore pressure, the models display a regular quiescence-activity phenomenon with a cycle length of 1/3-1 of the recurrence pened. When the model is under high stress or high pore pressure, this phenomenon becomes irregular or inexplicit. When the model is subject to periedic boundary forces and the amplitude of force variation is not too small, it results in an alternatively quiet and active seismicity Pattern with the same Period Of the force variation.展开更多
The active region AR5629 had looked quiet since it appeared from east limb onAug. 4th, there were some faculae aronud sunspot, two long filaments connected with thesunspot. On 9th, the filaments in active region becam...The active region AR5629 had looked quiet since it appeared from east limb onAug. 4th, there were some faculae aronud sunspot, two long filaments connected with thesunspot. On 9th, the filaments in active region became short and arched, We observedtwo class S flares, one of them (1005 UT) was SF / C3. 2 class. On 10th, we took展开更多
The quiet steel has been favored by automobile manufacturers for its advantage in shock absorption and noise reduction.However,there is less research on the welding performance of quiet steel plates.In this paper,the ...The quiet steel has been favored by automobile manufacturers for its advantage in shock absorption and noise reduction.However,there is less research on the welding performance of quiet steel plates.In this paper,the welding lobe of 1.0 mm quiet steel is studied.The comprehensive evaluation of spot welded joints was carried out by evaluation methods such as metallographic structure,microhardness,shear tensile and cross-tensile.The result showed that when the welding heat input was small,the interlayer of the quiet steel plate was not completely fused,and when the heat input was enough,the composite interlayer is completely fused with the steel plate,and the mechanical properties were good.The welding lobe of the quiet steel reaches 4.2 kA with good comprehensive mechanical properties and good weldability.展开更多
文摘What the newly established mediation body in China’s Hong Kong means for Africa In a world fraying under geopoliti-cal tensions,legal asymmetry,and fragmented global governance,the launch of the International Organisation for Mediation(IOMed)in China’s Hong Kong on 30 May is much more than a diplomatic novelty.It is a strategic recalibration of how the Global South,particularly African nations,might resolve disputes without surrendering sovereignty or dignity.
文摘Hi, everyone! I'd like to tell you something about my dream home. It is in a quiet place far away from the city.It's a big house with two floors. On the ground floor, there is a bright kitchen and a dining room. We usually have nice meal(1) there. On the first floor, there are three bedrooms and a study. It's really nice to have a bedroom of my own.
文摘Owen McCafferty’s Quietly(2012),a two-hander set in an Irish pub,explores how the Troubles continue to shape everyday life in Northern Ireland-an aspect often overlooked in official narratives that celebrate the success of the peace process.The presence of an immigrant character and modern communication devices in the traditional Irish pub setting signifies a new phase of Northern Irish society following the signing of the Good Friday Agreement.However,the tense and fragmented conversation between the protagonists,along with their sense of disorientation,reveals the persistence of sectarian divisions and the paralysis of everyday life,which,in turn,reinforce narrow conceptions of identity and lead to the ongoing cycle of violence.By bringing the two protagonists together to confront their past and jointly recount the most devastating day of their lives under the witness of a third party,McCafferty presents the possibility of transcending decades of division at the everyday level,suggesting that true peace requires not only political agreements but also open dialogue between opposing sides and a renewal of values through the enrichment of individual lived experiences.
基金supported by the National Natural Science Foundation of China(Grant Nos.52179099 and U23A6018)The funding supported by the Natural Science Foundation of Hebei Province,China(Grant No.2020HBQZYC001)were also acknowledged.
文摘Rock subjected to freeze-thaw(F-T)cycles may experience alterations in structural integrity and potentially impact its strength.This study investigates the effects of F-T cycles on granite by analyzing the acoustic emission(AE)signals recorded during uniaxial compression tests,characterizing the damage responses of the granite influenced by repeated F-T cycles.The results indicate significant reductions in uniaxial compression strength(UCS)and P-wave velocity as the number of F-T cycles increases.AE analysis reveals progressive damage accumulation,characterized by distinct stages of microcrack development.A parameter,AE energy intensity,is introduced to describe the failure process,showing that the typical AE quiet period in the failure stage is absent in granite pretreated with F-T cycles.Using the superlet transform method,AE frequency and amplitude are analyzed,revealing amplitude evolutions across three frequency domains.The results show that decreasing portions of signals in the highfrequency domain for granite are influenced by F-T cycles.These findings enhance understanding of rock degradation under F-T cycles,offering valuable implications for rock engineering in cold regions.
基金Projects (2013BAB02B01, 2013BAB02B03) supported by the Key Projects in the National Science & Technoogy Pillar Program During the Twelfth Five-Year Plan PeriodProjects (51274055, 51204030, 51204031, 51109035) supported by the National Natural Science Foundation of ChinaProjects (N110301006, N110501001, N110401003) supportecd by the Fundamental Research Funds for the Central Unviersity, China
文摘Acoustic emission （AE） technique is a useful tool for investigating rock damage mechanism, and is used to study the temporal-spatial evolution process of microcracks during the similar pillar material experiment. A combined AE location algorithm was developed based on the Least square algorithm and Geiger location algorithm. The pencil break test results show that the location precision can meet the demand of microcrack monitoring. The 3D location of AE events can directly reflect the process of initiation, propagation and evolutionary of microcracks. During the loading process, stress is much likely concentrated on the area between pillar and roof of the specimen, where belongs to danger zone of macroscopic failure. When rock reaches its plastic deformation stage, AE events begin to decrease, which indicates that AE quiet period can be seen as precursor characteristic of rock failure.
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A high-performance vibration isolation platform （VIP） has been developed for a cluster of control moment gyroscopes （CMGs）. CMGs have long been used for satellite attitude control. In this paper, the influence of flexible solar arrays on a passive multi-strut VIP of CMGs for a satellite is analyzed. The reasonable parameters design of flexi- ble solar arrays is discussed. Firstly, the dynamic model of the integrated satellite with flexible solar arrays, the VIP and CMGs is conducted by Newton-Euler method. Then based on reasonable assumptions, the transmissibility matrix of the VIP is derived. Secondly, the influences of the flexible solar arrays on both the performance of the VIP and the stability of closed-loop control systems are analyzed in detail. The parameter design limitation of these solar arrays is discussed. At last, by selecting reasonable parameters for both the VIP and flexible solar arrays, the attitude stabilization performance with vibration isolation system is predicted via simulation.
基金supported by Grants from the National Natural Science Foundation of China(No.52004016)the Postdoctoral Research Foundation of China(No.2021M700371)+3 种基金the Major Science and Technology Innovation Project of Shandong Province(No.2019SDZY02)the Open Fund Project of Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard(No.2021SKMS05)Science and Technology Support Plan Project of Guizhou Province(No.[2021]515)The authors are grateful to the anonymous referees for their precious comments and suggestions.
文摘Efcient and accurate monitoring and early warning of coal dynamic disaster and other disasters can provide guarantee for the efcient operation of mine transportation system.However,the traditional threshold early warning method often fails to warning some accidents.To address above issues,a new early warning method was proposed based on"quiet period"phenomenon of AE and EMR during fracture.It is found that,a"quiet period"of AE and EMR was present before the load reaches the peak stress,which could be used as one of the precursors to warn the imminent failure of coal and rock specimens.MS and AE signals increased abnormally followed by the phenomenon of"quiet period"before the occurrence of coal dynamic disaster on site,and the decrease of MS events in the"quiet period"is about 57%–88%compared with that in previous abnormal increase stage.During the damage evolution of coal and rock,"quiet period"phenomenon usually occurred at 85%–90%of the peak stress,where the slope of damage parameter curve is almost zero.The"quiet period"of the AE-EMR signals and the low change rate of damage parameter before failure provide a theoretical foundation for the coal dynamic disaster warning based on the"quiet period"precursor found in MS-AE-EMR monitoring system.These fndings will help reduce the number of under-reported events and improve early warning accuracy.
文摘There is a growing body of evidence that interest rate spreads in Africa are higher for big banks compared to small banks.One concern is that big banks might be using their market power to charge higher lending rates as they become larger,more efficient,and unchallenged.In contrast,several studies found that when bank size increases beyond certain thresholds,diseconomies of scale are introduced that lead to inefficiency.In that case,we also would expect to see widened interest margins.This study examines the connection between bank size and efficiency to understand whether that relationship is influenced by exploitation of market power or economies of scale.Using a panel of 162 African banks for 2001–2011,we analyzed the empirical data using instrumental variables and fixed effects regressions,with overlapping and non-overlapping thresholds for bank size.We found two key results.First,bank size increases bank interest rate margins with an inverted U-shaped nexus.Second,market power and economies of scale do not increase or decrease the interest rate margins significantly.The main policy implication is that interest rate margins cannot be elucidated by either market power or economies of scale.Other implications are discussed.
文摘Mr Michael Dobbs’ article The ABCs of the U.S.A.: America Seen with European Eyes shows the readers 26 points about the American culture. My teaching of it helps grow in me a strong inclination to give a talk about the following three aspects: a. The American individualism; b. Its quiet surroundings; c. The American people’s attitude toward work. My impression of them has helped me in my understanding of the American culture and its language, so I hope my paper will produce the similar effect on other English learners.
文摘This study deals with Peak of electron density in F2-layer sensibility scale during quiet time on solar minimum. Peaks of electron density in F2-layer (NmF2) values at the quietest days are compared to those carried out from the two nearest days (previous and following of quietest day). The study uses International Reference Ionosphere (IRI) for ionosphere modeling. The located station is Ouagadougou, in West Africa. Solar minimum of phase 22 is considered in this study. Using three core principles of ionosphere modeling under IRI running conditions, the study enables to carry out Peak of electron density in F2-layer values during the quietest days of the characteristic months for the four different seasons. These parameters are compared to those of the previous and the following of the quietest days (the day before and following each quietest selected day) at the same hour. The knowledge of NmF2 values at the quietest days and at the two nearest days enables to calculate the relative error that can be made on this parameter. This calculation highlights insignificant relative errors. This means that NmF2 values at the two nearest days of each quietest day on solar minimum can be used for simulating the quietest days’ behavior. NmF2 values obtained by running IRI model have good correlation with those carried out by Thermosphere-Ionosphere-Electrodynamics-General Circulation Model (TIEGCM).
基金Military Medical Science and Technology Research During the Eleventh Five-Year Plan,No. 06MA96
文摘The present study analyzed changes in the biochemical metabolites N-acetyl aspartate, choline, and creatine in a simple concussion rabbit model following quiet rest, hyperbaric oxygen therapy, or interference stimulation through the use of hydrogen proton magnetic resonance spectroscopy detection. Experimental findings showed that brain N-acetyl aspartate and choline peak values significantly decreased, while creatine peak values significantly increased following simple concussion. Following treatments, N-acetyl aspartate and choline peaks returned to normal levels in the quiet rest and hyperbaric oxygen therapy groups, but no changes were observed in the interference stimulation group. Results demonstrated abnormal changes in the brain biochemical metabolism environment following simple concussion. Quiet rest was shown to play an important role in restoration of biochemical metabolism following simple concussion.
文摘In this paper we simulate the repeated occurrence of strong earthquakes along a strike-slip fault by using a finite element model. The fault valve mechanism is included in the model in order to take into account the effeCt of POre fluid pressure variation. Five parameters are used to characterize the rheology of the fault, POre pressure variation, and fracture criteria. By Systematically varying these parameters and calculating a large number of models we carried out a preliminary investigation on the alternatively quiet and active periods of seismicity and their relation to model Parameters and loading conditions. Under the action of a constant-rate boundary movement, in the case of intermediate stress and pore pressure, the models display a regular quiescence-activity phenomenon with a cycle length of 1/3-1 of the recurrence pened. When the model is under high stress or high pore pressure, this phenomenon becomes irregular or inexplicit. When the model is subject to periedic boundary forces and the amplitude of force variation is not too small, it results in an alternatively quiet and active seismicity Pattern with the same Period Of the force variation.
文摘The active region AR5629 had looked quiet since it appeared from east limb onAug. 4th, there were some faculae aronud sunspot, two long filaments connected with thesunspot. On 9th, the filaments in active region became short and arched, We observedtwo class S flares, one of them (1005 UT) was SF / C3. 2 class. On 10th, we took
文摘The quiet steel has been favored by automobile manufacturers for its advantage in shock absorption and noise reduction.However,there is less research on the welding performance of quiet steel plates.In this paper,the welding lobe of 1.0 mm quiet steel is studied.The comprehensive evaluation of spot welded joints was carried out by evaluation methods such as metallographic structure,microhardness,shear tensile and cross-tensile.The result showed that when the welding heat input was small,the interlayer of the quiet steel plate was not completely fused,and when the heat input was enough,the composite interlayer is completely fused with the steel plate,and the mechanical properties were good.The welding lobe of the quiet steel reaches 4.2 kA with good comprehensive mechanical properties and good weldability.
