Peking Union Medical College(PUMC)launched the"4+4"Medical Doctor(MD)pilot program in 2018,admitting students with non-medical backgrounds from top universities,aligning with national medical talent training...Peking Union Medical College(PUMC)launched the"4+4"Medical Doctor(MD)pilot program in 2018,admitting students with non-medical backgrounds from top universities,aligning with national medical talent training policies to foster diverse and eager learners in medicine.On the occasion of the graduation of the first class of the"4+4"MD pilot class at PUMC in 2023,we reviewed the teaching reform in the pilot program and carried out a systematic survey and interviews with students,faculties,and management staff of the pilot class.This article reports on the measures taken by the pilot class at PUMC in enrollment and curriculum setting,and demonstrates the achievements of the pilot class in terms of student academic background structure,knowledge acquisition and skill learning,scientific research ability,and course evaluation.The results indicated that the pilot class had met the national demand for the"Medicine+X"talent training model.More specifically,with a diverse academic backgrounds,the pilot class graduates had academic levels comparable to the eight-year medical education graduates,and their scientific research abilities were satisfactory.The pilot program at PUMC will optimize the curriculum setting,strengthen the construction of faculty,learning resources,and teaching facilities,and reform the academic evaluation methods,thus deepening the reform of medical education and improving the"4+4"MD program as a novel medical education model.展开更多
Background: Cervical Intraepithelial neoplasia treatments have become essential interventions to manage cervical lesions. Majority of the recipients of these treatments are women within the reproductive age group, who...Background: Cervical Intraepithelial neoplasia treatments have become essential interventions to manage cervical lesions. Majority of the recipients of these treatments are women within the reproductive age group, who according to literature may be at risk of adverse pregnancy outcomes. This pilot study is part of a study investigating adverse pregnancy outcomes among women who received Cryotherapy, Thermal ablation and Loop Electrosurgical Excision Procedure compared to the untreated women in Zambia. Materials and Methods: This descriptive study analyzed records of 886 (n = 443 treated and n = 443 untreated) women aged 15 - 49 years. The women were either screened with Visual Inspection with Acetic Acid or treated for Cervical Intraepithelial neoplasia at the Adult Infectious Disease Centre between January 2010 and December 2020. Women meeting the criteria were identified using the Visual Inspection with Acetic Acid screening records and telephone interviews to obtain the adverse pregnancy outcome experienced. Data were analysed using STATA version 16 to determine the prevalence and obtain frequency distribution of outcomes of interest. Univariate and multivariable binary logistic regression estimated odds of adverse pregnancy outcomes across the three treatments. Results: The respondents were aged 15 to 49 years. Adverse pregnancy outcomes were observed to be more prevalent in the treatment group (18.5%) compared to the untreated group (5.4%). Normal pregnancy outcomes were lower in the treated (46.3%;n = 443) than the untreated (53.7%;n = 443). The treated group accounted for the majority of abortions (85.2%), prolonged labour (85.7%) and low birth weight (80%), whereas, the untreated accounted for the majority of still births (72.7%). Women treated with cryotherapy (aOR = 2.43, 95% CI = 1.32 - 4.49, p = 0.004), thermal ablation (aOR = 6.37, 95% CI = 0.99 - 41.2, p = 0.052) and Loop Electrosurgical Excision Procedure (aOR = 9.67, 95% CI = 2.17 - 43.1, p = 0.003) had two-, six- and ten-times higher odds of adverse pregnancy outcomes respectively, relative to women who required no treatment. Conclusion: Adverse pregnancy outcomes are prevalent among women who have received treatment in Zambia. The findings indicate that treating Cervical Intraepithelial Neoplasia has been linked to higher chances of experiencing abortion, delivering low birth weight babies and enduring prolonged labor that may result in a caesarean section delivery. Cervical neoplasia treatments, particularly Loop Electrosurgical Excision Procedure, are associated with significantly increased odds of adverse pregnancy outcomes. It is essential to include information about prior Cervical Intraepithelial neoplasia treatment outcomes in obstetric care.展开更多
Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demo...Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demonstrative effect nationwide.The basic experience from a decade of FTZs includes:adhering to the centralized and unified leadership of the CPC Central Committee;combining top-level design with encouragement of grassroots innovation;leveraging the distinct characteristics and strengths of FTZs to form a differentiated development pattern;maintaining the integration of opening up with domestic reforms;using openness to drive reforms;and organically combining openness with national security assurance.Under the current and future new circumstances,China’s FTZs face new challenges and tasks.In accordance with the directives of the 20th National Congress of the Communist Party of China,an enhancement strategy for the FTZs needs to be implemented.This involves the following:First,accurately understanding and responding to the changing situation to create strategic opportunities.Second,shifting paradigms to implement innovation-driven strategies,using the new development pattern concept to guide the reform experiments and construction of the FTZs.Third,granting more autonomy to FTZs for reforms,pursuing progress while maintaining stability,and solidly advancing the reform experiments in the FTZs.Fourth,orderly expanding the opening up of the service sector and cautiously advancing the internationalization of the renminbi.Fifth,promoting innovative development in trade to build a strong trade nation.Sixth,establishing synergy with bilateral FTZs,Belt and Road cooperation,and national diplomatic strategies to enhance the linkage effect.展开更多
Orthogonal time frequency space(OTFS)modulation has been proven to be superior to traditional orthogonal frequency division multiplexing(OFDM)systems in high-speed communication scenarios.However,the existing channel ...Orthogonal time frequency space(OTFS)modulation has been proven to be superior to traditional orthogonal frequency division multiplexing(OFDM)systems in high-speed communication scenarios.However,the existing channel estimation schemes may results in poor peak to average power ratio(PAPR)performance of OTFS system or low spectrum efficiency.Hence,in this paper,we propose a low PAPR channel estimation scheme with high spectrum efficiency.Specifically,we design a multiple scattered pilot pattern,where multiple low power pilot symbols are superimposed with data symbols in delay-Doppler domain.Furthermore,we propose the placement rules for pilot symbols,which can guarantee the low PAPR.Moreover,the data aided iterative channel estimation was invoked,where joint channel estimation is proposed by exploiting multiple independent received signals instead of only one received signal in the existing scheme,which can mitigate the interference imposed by data symbols for channel estimation.Simulation results shows that the proposed multiple scattered pilot aided channel estimation scheme can significantly reduce the PAPR while keeping the high spectrum efficiency.展开更多
The robot pilot is a new concept of a robot system that pilots a manned aircraft,thereby forming a new type of unmanned aircraft system(UAS)that makes full use of the platform maturity,load capacity,and airworthiness ...The robot pilot is a new concept of a robot system that pilots a manned aircraft,thereby forming a new type of unmanned aircraft system(UAS)that makes full use of the platform maturity,load capacity,and airworthiness of existing manned aircraft while greatly expanding the operation and application fields of UASs.In this research,the implementation and advantages of the robot pilot concept are discussed in detail,and a helicopter robot pilot is proposed to fly manned helicopters.The robot manipulators are designed according to the handling characteristics of the helicopter-controlling mechanism.Based on a kinematic analysis of the robot manipulators,a direct-driving method is established for the robot flight controller to reduce the time delay and control error of the robot servo process.A supporting ground station is built to realize different flight modes and the functional integration of the robot pilot.Finally,a prototype of the helicopter robot pilot is processed and installed in a helicopter to carry out flight tests.The test results show that the robot pilot can independently fly the helicopter to realize forward flight,backward flight,side flight,and turning flight,which verifies the effectiveness of the helicopter robot pilot.展开更多
How to accurately recognize the mental state of pilots is a focus in civil aviation safety.The mental state of pilots is closely related to their cognitive ability in piloting.Whether the cognitive ability meets the s...How to accurately recognize the mental state of pilots is a focus in civil aviation safety.The mental state of pilots is closely related to their cognitive ability in piloting.Whether the cognitive ability meets the standard is related to flight safety.However,the pilot’s working state is unique,which increases the difficulty of analyzing the pilot’s mental state.In this work,we proposed a Convolutional Neural Network(CNN)that merges attention to classify the mental state of pilots through electroencephalography(EEG).Considering the individual differences in EEG,semi-supervised learning based on improvedK-Means is used in themodel training to improve the generalization ability of the model.We collected the EEG data of 12 pilot trainees during the simulated flight and compared the method in this paper with other methods on this data.The method in this paper achieved an accuracy of 86.29%,which is better than 4D-aNN and HCNN etc.Negative emotion will increase the probability of fatigue appearing,and emotion recognition is also meaningful during the flight.Then we conducted experiments on the public dataset SEED,and our method achieved an accuracy of 93.68%.In addition,we combine multiple parameters to evaluate the results of the classification network on a more detailed level and propose a corresponding scoring mechanism to display the mental state of the pilots directly.展开更多
An experimental study is conducted on several retro-reflective beamforming schemes for wireless power transmission to multiple wireless power receivers(referred to herein as“targets”).The experimental results demons...An experimental study is conducted on several retro-reflective beamforming schemes for wireless power transmission to multiple wireless power receivers(referred to herein as“targets”).The experimental results demonstrate that,when multiple targets broadcast continuous-wave pilot signals at respective frequencies,a retro-reflective wireless power transmitter is capable of generating multiple wireless power beams aiming at the respective targets as long as the multiple pilot signals are explicitly separated from one another by the wireless power transmitter.However,various practical complications are identified when the pilot signals of multiple targets are not appropriately differentiated from each other by the wireless power transmitter.Specifically,when multiple pilot signals are considered to be carried by the same frequency,the wireless power transmission performance becomes heavily dependent on the interaction among the pilot signals,which is highly undesirable in practice.In conclusion,it is essential for a retro-reflective wireless power transmitter to explicitly discriminate multiple targets’pilot signals among each other.展开更多
A domestic balloon-type digester with 1200 liters of substrate and a 700-litre gas reserve was installed at the Université Gaston Berger pilot farm, which has 4 cows. After an initial load of 1000 L of water, 90 ...A domestic balloon-type digester with 1200 liters of substrate and a 700-litre gas reserve was installed at the Université Gaston Berger pilot farm, which has 4 cows. After an initial load of 1000 L of water, 90 L of bovine rumen and 145 L of cow dung, the functional parameters of the reaction medium, i.e., temperature, pH, salinity and conductimetry, were regularly monitored at a rate of 3 tests per day until the thirtieth day, corresponding to the flame test and the start of analysis and daily loading of the biodigester. The analysis of the biogas obtained after the flame test showed us the considerable contribution of bovine hindquarters to the CH4 fraction, which reached 72.2% from the start of the production phase. As anaerobic digestion is both a complex and multiparametric process, microbiological analysis revealed the presence of several strains of bacteria in the substrate used. Among the most abundant were Escherichia coli, Klebsiella spp, non-fermentative Gram-negative bacilli and Enterococcus sp. However, the bacterial strain that interests us most in anaerobic digestion is the non-fermentative Gram-negative family. We see the identification and temporal monitoring of these families of bacteria as a major step forward in the control of anaerobic fermentation processes in the Sahelian context and in Senegal in particular.展开更多
Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the ti...Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the tight matrix,complex fracture system,low production level of producers,and low recovery factor ofMblock in Xinjiang oilfield,it is selected for on-site pilot test of nitrogen foam flooding.Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors.The pressure index,filling degree,and fluid injection profile are found to be all improved in injectors after injection of nitrogen foam.The oil production,water cut and liquid production file are also improved in most of the producers,with the natural decline rate in the test area become slow.Results show that nitrogen foam flooding technology can be good technical storage for enhanced oil recovery in low permeability reservoir.展开更多
On April 10th,2023,Shanghai Medical Products Administration released a notice on publicly asking for opinions about Rules for the On-site Personalized Service Examination of Ordinary Cosmetics of Shanghai Pudong New A...On April 10th,2023,Shanghai Medical Products Administration released a notice on publicly asking for opinions about Rules for the On-site Personalized Service Examination of Ordinary Cosmetics of Shanghai Pudong New Area(Trial)(exposure draft).This notice mainly explained the targeted group,purpose of release,condition of applying for filing,rules which organizations and relevant people should obey,quality administration system of personalized cosmetics.展开更多
The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into...The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities.展开更多
Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of...Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of transferring pilot,proposed that pilot boat shall have the function of ensuring the safety of pilot when embarking or disembarking the ships,some suggestions on the future design and manufacture of Chinese pilot boats are also given according to the advantages and disadvantages of domestic and foreign pilot boats.展开更多
Background: The objective of this pilot study was to describe clinical profile, electric, echocardiographic and angiographic caracteristics with procedural outcome of congolease patients undergoing coronarography in t...Background: The objective of this pilot study was to describe clinical profile, electric, echocardiographic and angiographic caracteristics with procedural outcome of congolease patients undergoing coronarography in the first and only one cardiac catheterization center opened in Kinshasa. Methods: An analytical cross-sectional study was carried out over a period from October 2019 (date of establishment of the first coronary angiography unit in DR Congo) to March 2021. We proceeded to a serial sampling of the consecutive cases of all the patients who have an angiographic exploration of coronary arteries. Clinical, ECG and cardiac ultrasound data were collected in all patients. The indications for the coronary angiography examination were set by differents cardiologists on the basis of repolarization troubles in the electrocardiogram, cinetic troubles in echocardiography, positive stress test and chest pain in patients with cardiovascular risq factors. Results: The serie (47 patients) was predominantly male with a sex ratio M/W of 2.6. The average age was 59.8 ± 10.5 years. Arterial hypertension (HBP) was the main risk factor (89.4%);followed by diabetes mellitus (14.9%). Chest pain was the main functional sign with an atypical character in 44.7%. The ECG showed ST segment depression (17%) and T wave inversion (17%), the anterior region being the most affected. Hypokinesia was the most common echocardiographic abnormality (34%), followed by akinesia (10.6%). The anteroseptal and apical territories were affected in 12.8%. Dilated myocardiopathy (DMC) was significantly predominant in the male sex (29.4% vs 7.7%;p = 0.011). With radial puncture as the main approach, coronary angiography was pathological in 44% revealing mono-truncal lesions. The left coronary network was the most affected: the middle inter ventricular artery (12.8%), the proximal interventricular artery (10.6%) and the proximal circonflex artery (10.6%). In multivariate logistic regression analysis, age (for age > 50 years for men and >60 years for women), arterial hypertension and dilated cardiomyopathy emerged as independent determinants of pathological coronary angiography. Transluminal angioplasty was performed in 27.7% of patients. The bypass indication was retained in 4.3% of cases and medical treatment in 68%. Conclusion: Coronary angiography was used to diagnose lesions responsible for ischemic heart disease and to treat 27.7% of patients locally. The young age of patients and limited financial resources encourage the strengthening of preventive measures against cardio vascular risq factors.展开更多
文摘Peking Union Medical College(PUMC)launched the"4+4"Medical Doctor(MD)pilot program in 2018,admitting students with non-medical backgrounds from top universities,aligning with national medical talent training policies to foster diverse and eager learners in medicine.On the occasion of the graduation of the first class of the"4+4"MD pilot class at PUMC in 2023,we reviewed the teaching reform in the pilot program and carried out a systematic survey and interviews with students,faculties,and management staff of the pilot class.This article reports on the measures taken by the pilot class at PUMC in enrollment and curriculum setting,and demonstrates the achievements of the pilot class in terms of student academic background structure,knowledge acquisition and skill learning,scientific research ability,and course evaluation.The results indicated that the pilot class had met the national demand for the"Medicine+X"talent training model.More specifically,with a diverse academic backgrounds,the pilot class graduates had academic levels comparable to the eight-year medical education graduates,and their scientific research abilities were satisfactory.The pilot program at PUMC will optimize the curriculum setting,strengthen the construction of faculty,learning resources,and teaching facilities,and reform the academic evaluation methods,thus deepening the reform of medical education and improving the"4+4"MD program as a novel medical education model.
文摘Background: Cervical Intraepithelial neoplasia treatments have become essential interventions to manage cervical lesions. Majority of the recipients of these treatments are women within the reproductive age group, who according to literature may be at risk of adverse pregnancy outcomes. This pilot study is part of a study investigating adverse pregnancy outcomes among women who received Cryotherapy, Thermal ablation and Loop Electrosurgical Excision Procedure compared to the untreated women in Zambia. Materials and Methods: This descriptive study analyzed records of 886 (n = 443 treated and n = 443 untreated) women aged 15 - 49 years. The women were either screened with Visual Inspection with Acetic Acid or treated for Cervical Intraepithelial neoplasia at the Adult Infectious Disease Centre between January 2010 and December 2020. Women meeting the criteria were identified using the Visual Inspection with Acetic Acid screening records and telephone interviews to obtain the adverse pregnancy outcome experienced. Data were analysed using STATA version 16 to determine the prevalence and obtain frequency distribution of outcomes of interest. Univariate and multivariable binary logistic regression estimated odds of adverse pregnancy outcomes across the three treatments. Results: The respondents were aged 15 to 49 years. Adverse pregnancy outcomes were observed to be more prevalent in the treatment group (18.5%) compared to the untreated group (5.4%). Normal pregnancy outcomes were lower in the treated (46.3%;n = 443) than the untreated (53.7%;n = 443). The treated group accounted for the majority of abortions (85.2%), prolonged labour (85.7%) and low birth weight (80%), whereas, the untreated accounted for the majority of still births (72.7%). Women treated with cryotherapy (aOR = 2.43, 95% CI = 1.32 - 4.49, p = 0.004), thermal ablation (aOR = 6.37, 95% CI = 0.99 - 41.2, p = 0.052) and Loop Electrosurgical Excision Procedure (aOR = 9.67, 95% CI = 2.17 - 43.1, p = 0.003) had two-, six- and ten-times higher odds of adverse pregnancy outcomes respectively, relative to women who required no treatment. Conclusion: Adverse pregnancy outcomes are prevalent among women who have received treatment in Zambia. The findings indicate that treating Cervical Intraepithelial Neoplasia has been linked to higher chances of experiencing abortion, delivering low birth weight babies and enduring prolonged labor that may result in a caesarean section delivery. Cervical neoplasia treatments, particularly Loop Electrosurgical Excision Procedure, are associated with significantly increased odds of adverse pregnancy outcomes. It is essential to include information about prior Cervical Intraepithelial neoplasia treatment outcomes in obstetric care.
文摘Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demonstrative effect nationwide.The basic experience from a decade of FTZs includes:adhering to the centralized and unified leadership of the CPC Central Committee;combining top-level design with encouragement of grassroots innovation;leveraging the distinct characteristics and strengths of FTZs to form a differentiated development pattern;maintaining the integration of opening up with domestic reforms;using openness to drive reforms;and organically combining openness with national security assurance.Under the current and future new circumstances,China’s FTZs face new challenges and tasks.In accordance with the directives of the 20th National Congress of the Communist Party of China,an enhancement strategy for the FTZs needs to be implemented.This involves the following:First,accurately understanding and responding to the changing situation to create strategic opportunities.Second,shifting paradigms to implement innovation-driven strategies,using the new development pattern concept to guide the reform experiments and construction of the FTZs.Third,granting more autonomy to FTZs for reforms,pursuing progress while maintaining stability,and solidly advancing the reform experiments in the FTZs.Fourth,orderly expanding the opening up of the service sector and cautiously advancing the internationalization of the renminbi.Fifth,promoting innovative development in trade to build a strong trade nation.Sixth,establishing synergy with bilateral FTZs,Belt and Road cooperation,and national diplomatic strategies to enhance the linkage effect.
基金supported by National Natural Science Foundation of China(No.61871452)。
文摘Orthogonal time frequency space(OTFS)modulation has been proven to be superior to traditional orthogonal frequency division multiplexing(OFDM)systems in high-speed communication scenarios.However,the existing channel estimation schemes may results in poor peak to average power ratio(PAPR)performance of OTFS system or low spectrum efficiency.Hence,in this paper,we propose a low PAPR channel estimation scheme with high spectrum efficiency.Specifically,we design a multiple scattered pilot pattern,where multiple low power pilot symbols are superimposed with data symbols in delay-Doppler domain.Furthermore,we propose the placement rules for pilot symbols,which can guarantee the low PAPR.Moreover,the data aided iterative channel estimation was invoked,where joint channel estimation is proposed by exploiting multiple independent received signals instead of only one received signal in the existing scheme,which can mitigate the interference imposed by data symbols for channel estimation.Simulation results shows that the proposed multiple scattered pilot aided channel estimation scheme can significantly reduce the PAPR while keeping the high spectrum efficiency.
基金supported by the National Natural Science Foundation of China(11972059)。
文摘The robot pilot is a new concept of a robot system that pilots a manned aircraft,thereby forming a new type of unmanned aircraft system(UAS)that makes full use of the platform maturity,load capacity,and airworthiness of existing manned aircraft while greatly expanding the operation and application fields of UASs.In this research,the implementation and advantages of the robot pilot concept are discussed in detail,and a helicopter robot pilot is proposed to fly manned helicopters.The robot manipulators are designed according to the handling characteristics of the helicopter-controlling mechanism.Based on a kinematic analysis of the robot manipulators,a direct-driving method is established for the robot flight controller to reduce the time delay and control error of the robot servo process.A supporting ground station is built to realize different flight modes and the functional integration of the robot pilot.Finally,a prototype of the helicopter robot pilot is processed and installed in a helicopter to carry out flight tests.The test results show that the robot pilot can independently fly the helicopter to realize forward flight,backward flight,side flight,and turning flight,which verifies the effectiveness of the helicopter robot pilot.
基金This research is supported by program of Key Laboratory of Flight Technology and Flight Safety(FZ2020KF07)Ms.ZaijunWang received the grant.This research is also supported by Postgraduate Innovation Project of CAFUC(X2021-37)Mr.Qianlei Wang received the grant.
文摘How to accurately recognize the mental state of pilots is a focus in civil aviation safety.The mental state of pilots is closely related to their cognitive ability in piloting.Whether the cognitive ability meets the standard is related to flight safety.However,the pilot’s working state is unique,which increases the difficulty of analyzing the pilot’s mental state.In this work,we proposed a Convolutional Neural Network(CNN)that merges attention to classify the mental state of pilots through electroencephalography(EEG).Considering the individual differences in EEG,semi-supervised learning based on improvedK-Means is used in themodel training to improve the generalization ability of the model.We collected the EEG data of 12 pilot trainees during the simulated flight and compared the method in this paper with other methods on this data.The method in this paper achieved an accuracy of 86.29%,which is better than 4D-aNN and HCNN etc.Negative emotion will increase the probability of fatigue appearing,and emotion recognition is also meaningful during the flight.Then we conducted experiments on the public dataset SEED,and our method achieved an accuracy of 93.68%.In addition,we combine multiple parameters to evaluate the results of the classification network on a more detailed level and propose a corresponding scoring mechanism to display the mental state of the pilots directly.
基金supported in part by the National Natural Science Foundation of China(61871220)the Natural Science Foundation of Jiangsu Province(BK20201293)。
文摘An experimental study is conducted on several retro-reflective beamforming schemes for wireless power transmission to multiple wireless power receivers(referred to herein as“targets”).The experimental results demonstrate that,when multiple targets broadcast continuous-wave pilot signals at respective frequencies,a retro-reflective wireless power transmitter is capable of generating multiple wireless power beams aiming at the respective targets as long as the multiple pilot signals are explicitly separated from one another by the wireless power transmitter.However,various practical complications are identified when the pilot signals of multiple targets are not appropriately differentiated from each other by the wireless power transmitter.Specifically,when multiple pilot signals are considered to be carried by the same frequency,the wireless power transmission performance becomes heavily dependent on the interaction among the pilot signals,which is highly undesirable in practice.In conclusion,it is essential for a retro-reflective wireless power transmitter to explicitly discriminate multiple targets’pilot signals among each other.
文摘A domestic balloon-type digester with 1200 liters of substrate and a 700-litre gas reserve was installed at the Université Gaston Berger pilot farm, which has 4 cows. After an initial load of 1000 L of water, 90 L of bovine rumen and 145 L of cow dung, the functional parameters of the reaction medium, i.e., temperature, pH, salinity and conductimetry, were regularly monitored at a rate of 3 tests per day until the thirtieth day, corresponding to the flame test and the start of analysis and daily loading of the biodigester. The analysis of the biogas obtained after the flame test showed us the considerable contribution of bovine hindquarters to the CH4 fraction, which reached 72.2% from the start of the production phase. As anaerobic digestion is both a complex and multiparametric process, microbiological analysis revealed the presence of several strains of bacteria in the substrate used. Among the most abundant were Escherichia coli, Klebsiella spp, non-fermentative Gram-negative bacilli and Enterococcus sp. However, the bacterial strain that interests us most in anaerobic digestion is the non-fermentative Gram-negative family. We see the identification and temporal monitoring of these families of bacteria as a major step forward in the control of anaerobic fermentation processes in the Sahelian context and in Senegal in particular.
基金supported by the Prospective and Fundamental Project of CNPC“Study on the EOR Technology by Foam Flooding(2021DJ1603)”by Open Fund of State Key Laboratory of Enhanced Oil Recovery,CNPC(2022-KFKT-29).
文摘Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the tight matrix,complex fracture system,low production level of producers,and low recovery factor ofMblock in Xinjiang oilfield,it is selected for on-site pilot test of nitrogen foam flooding.Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors.The pressure index,filling degree,and fluid injection profile are found to be all improved in injectors after injection of nitrogen foam.The oil production,water cut and liquid production file are also improved in most of the producers,with the natural decline rate in the test area become slow.Results show that nitrogen foam flooding technology can be good technical storage for enhanced oil recovery in low permeability reservoir.
文摘On April 10th,2023,Shanghai Medical Products Administration released a notice on publicly asking for opinions about Rules for the On-site Personalized Service Examination of Ordinary Cosmetics of Shanghai Pudong New Area(Trial)(exposure draft).This notice mainly explained the targeted group,purpose of release,condition of applying for filing,rules which organizations and relevant people should obey,quality administration system of personalized cosmetics.
基金Study on the Path of Promoting the Integration of“Three Societies”and Help Rural Revitalization in Chongqing,Chongqing Social Science Planning Office[Grant number.2019WT13]Study on the Cultivation of Language Service Talents Under the Background of Belt and Road Initiative,Chongqing Social Science Planning Office[Grant number.2021WYZX12].
文摘The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities.
文摘Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of transferring pilot,proposed that pilot boat shall have the function of ensuring the safety of pilot when embarking or disembarking the ships,some suggestions on the future design and manufacture of Chinese pilot boats are also given according to the advantages and disadvantages of domestic and foreign pilot boats.
文摘Background: The objective of this pilot study was to describe clinical profile, electric, echocardiographic and angiographic caracteristics with procedural outcome of congolease patients undergoing coronarography in the first and only one cardiac catheterization center opened in Kinshasa. Methods: An analytical cross-sectional study was carried out over a period from October 2019 (date of establishment of the first coronary angiography unit in DR Congo) to March 2021. We proceeded to a serial sampling of the consecutive cases of all the patients who have an angiographic exploration of coronary arteries. Clinical, ECG and cardiac ultrasound data were collected in all patients. The indications for the coronary angiography examination were set by differents cardiologists on the basis of repolarization troubles in the electrocardiogram, cinetic troubles in echocardiography, positive stress test and chest pain in patients with cardiovascular risq factors. Results: The serie (47 patients) was predominantly male with a sex ratio M/W of 2.6. The average age was 59.8 ± 10.5 years. Arterial hypertension (HBP) was the main risk factor (89.4%);followed by diabetes mellitus (14.9%). Chest pain was the main functional sign with an atypical character in 44.7%. The ECG showed ST segment depression (17%) and T wave inversion (17%), the anterior region being the most affected. Hypokinesia was the most common echocardiographic abnormality (34%), followed by akinesia (10.6%). The anteroseptal and apical territories were affected in 12.8%. Dilated myocardiopathy (DMC) was significantly predominant in the male sex (29.4% vs 7.7%;p = 0.011). With radial puncture as the main approach, coronary angiography was pathological in 44% revealing mono-truncal lesions. The left coronary network was the most affected: the middle inter ventricular artery (12.8%), the proximal interventricular artery (10.6%) and the proximal circonflex artery (10.6%). In multivariate logistic regression analysis, age (for age > 50 years for men and >60 years for women), arterial hypertension and dilated cardiomyopathy emerged as independent determinants of pathological coronary angiography. Transluminal angioplasty was performed in 27.7% of patients. The bypass indication was retained in 4.3% of cases and medical treatment in 68%. Conclusion: Coronary angiography was used to diagnose lesions responsible for ischemic heart disease and to treat 27.7% of patients locally. The young age of patients and limited financial resources encourage the strengthening of preventive measures against cardio vascular risq factors.
