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Adverse Pregnancy Outcomes Following Cryotherapy, Thermal Ablation and Loop Electrosurgical Excision Procedure for Cervical Intraepithelial Neoplasia Treatment: A Pilot Study among Zambian Women
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作者 Victoria Mwiinga-Kalusopa Johanna E. Maree +1 位作者 Concepta Kwaleyela Patricia Katowa-Mukwato 《Open Journal of Obstetrics and Gynecology》 2024年第1期7-17,共11页
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
关键词 Adverse Pregnancy Outcomes Cervical Intraepithelial Neoplasia Cryothera-py Thermal Ablation Loop Electrosurgical Excision Procedure pilot Repro-ductive Age
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The Tenth Anniversary of Free Trade Pilot Zones in China:Fundamental Experiences and Enhancement Strategies
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作者 Pei Changhong 《China Economist》 2024年第3期2-20,共19页
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
关键词 Tenth anniversary of Free Trade pilot Zones experience summary enhancement strategy conception
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The Current Situation and Future Expectationsof China's Pilot Boatsl
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作者 Haidong Zhan 《现代交通(中英文版)》 2023年第1期1-8,共8页
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
关键词 pilot Boat pilot Transfer of pilot SAFETY RISK Current Situation Future Expectations
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Low PAPR Channel Estimation for OTFS with Scattered Superimposed Pilots 被引量:1
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作者 Wei Liu Liyi Zou +1 位作者 Baoming Bai Teng Sun 《China Communications》 SCIE CSCD 2023年第1期79-87,共9页
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
关键词 OTFS channel estimation superimposed pilots PAPR interference mitigation
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Robot Pilot:A New Autonomous System toward Flying Manned Aerial Vehicles
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作者 Zibo Jin Daochun Li Jinwu Xiang 《Engineering》 SCIE EI CAS CSCD 2023年第8期242-253,共12页
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
关键词 HELICOPTER Robot pilot Flight control Unmanned system
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On Differentiation Among Pilot Signals of Multiple Mobile Targets in Retro-Reflective Beamforming for Wireless Power Transmission
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作者 Xin Wang Long Li +1 位作者 Tie Jun Cui Mingyu Lu 《Engineering》 SCIE EI CAS CSCD 2023年第11期55-62,共8页
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
关键词 Wireless power transmission Microwave antenna array Retro-reflective beamforming pilot signal Multiple access
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A Method for Classification and Evaluation of Pilot’s Mental States Based on CNN
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作者 Qianlei Wang Zaijun Wang +2 位作者 Renhe Xiong Xingbin Liao Xiaojun Tan 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1999-2020,共22页
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
关键词 pilot mental state EEG ATTENTION CNN semi-supervised learning
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Pilot Test for Nitrogen Foam Flooding in Low Permeability Reservoir
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作者 Xinyu Zhou Jia Huang +5 位作者 Yuchen Qian Wenli Luo Lisha Qi Jie Wang Zhibin Jiang Hao Kang 《Energy Engineering》 EI 2023年第3期763-774,共12页
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
关键词 Fluid production profile nitrogen foam low permeability pilot test
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Does innovative city pilot policy promote urban green growth in China?An analysis of green total factor productivity,2005-2020
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作者 Hao Zhang Wenqing Tao Jun He 《Chinese Journal of Population,Resources and Environment》 2023年第3期145-154,共10页
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
关键词 Innovative city pilot policy Urban green total factor productivity growth Industrial agglomerations Difference-in-differences model methodology
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Study of the Activation Process of a 2 m3 Pilot Biodigester on a Microfarm Site
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作者 Jean-Baptiste Mansaly Djicknoum Diouf +4 位作者 Bruno Pirou Elhadji Mba Bamdo Diakhaby Seynabou Lo Amadou Seidou Maïga Diène Ndiaye 《Journal of Agricultural Chemistry and Environment》 2023年第4期397-413,共17页
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
关键词 pilot Digester Activation Bovine Belly Conductimetry SALINITY Microbiology Analysis
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“New Regulations”born regarding the pilot customized cosmetics
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《China Detergent & Cosmetics》 CAS 2023年第2期5-5,共1页
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
关键词 RELEASE CUSTOM pilot
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A Pilot Study about the First Cases of Coronary Angioplasty in Democratic Republic of Congo/Kinshasa: Patient Profile
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作者 David Ipungu Gondele Eulethère Vita Kintoki +9 位作者 Yves Lubenga Georges Ngoyi Trésor Mvunzi Dominique Mupepe Nathan Buila Zéphirin Kamuanga Fahd Qureshi Aliosha Nkodila Jean Robert Rissasi Makulo Jean René M’buyamba-Kabangu 《Case Reports in Clinical Medicine》 2023年第10期371-388,共18页
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
关键词 Heart Disease Coronary Angioplasty Patient Profile pilot Study Democratic Republic of Congo
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连续Pilot体制CDMA高速移动台自适应信道估计器 被引量:2
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作者 陈国安 尤肖虎 《东南大学学报(自然科学版)》 EI CAS CSCD 1999年第B11期1-5,共5页
提出了连续Pilot 信号体制CDMA系统中,高速移动台自适应信道估计的方法,它包括信道变化速率的检测和信道估计积分长度的自适应调整两个部分.仿真结果显示,该信道估计器有效拓展了移动台正常工作的运动速度范围,提高了R... 提出了连续Pilot 信号体制CDMA系统中,高速移动台自适应信道估计的方法,它包括信道变化速率的检测和信道估计积分长度的自适应调整两个部分.仿真结果显示,该信道估计器有效拓展了移动台正常工作的运动速度范围,提高了RAKE接收机的适应性. 展开更多
关键词 CDMA 信道估计 高速移动台 连续pilot体制
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Hybrid orthogonal and non-orthogonal pilot distribution based channel estimation in massive MIMO system 被引量:1
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作者 ZHANG Ruoyu ZHAO Honglin +1 位作者 ZHANG Jiayan JIA Shaobo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期881-898,共18页
How to obtain accurate channel state information(CSI)at the transmitter with less pilot overhead for frequency division duplexing(FDD) massive multiple-input multiple-output(MIMO)system is a challenging issue due to t... How to obtain accurate channel state information(CSI)at the transmitter with less pilot overhead for frequency division duplexing(FDD) massive multiple-input multiple-output(MIMO)system is a challenging issue due to the large number of antennas. To reduce the overwhelming pilot overhead, a hybrid orthogonal and non-orthogonal pilot distribution at the base station(BS),which is a generalization of the existing pilot distribution scheme,is proposed by exploiting the common sparsity of channel due to the compact antenna arrangement. Then the block sparsity for antennas with hybrid pilot distribution is derived respectively and can be used to obtain channel impulse response. By employing the theoretical analysis of block sparse recovery, the total coherence criterion is proposed to optimize the sensing matrix composed by orthogonal pilots. Due to the huge complexity of optimal pilot acquisition, a genetic algorithm based pilot allocation(GAPA) algorithm is proposed to acquire optimal pilot distribution locations with fast convergence. Furthermore, the Cramer Rao lower bound is derived for non-orthogonal pilot-based channel estimation and can be asymptotically approached by the prior support set, especially when the optimized pilot is employed. 展开更多
关键词 massive multiple-input multiple-output(MIMO) frequency division duplexing(FDD) compressed sensing hybrid pilot distribution genetic algorithm based pilot allocation(GAPA)
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iPAS:A deep Monte Carlo Tree Search-based intelligent pilot-power allocation scheme for massive MIMO system 被引量:1
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作者 Jienan Chen Siyu Luo +2 位作者 Lin Zhang Cong Zhang Bin Cao 《Digital Communications and Networks》 SCIE CSCD 2021年第3期362-372,共11页
Massive Multiple-Input-Multiple-Output(MIMO)is a promising technology to meet the demand for the connection of massive devices and high data capacity for mobile networks in the next generation communication system.How... Massive Multiple-Input-Multiple-Output(MIMO)is a promising technology to meet the demand for the connection of massive devices and high data capacity for mobile networks in the next generation communication system.However,due to the massive connectivity of mobile devices,the pilot contamination problem will severely degrade the communication quality and spectrum efficiency of the massive MIMO system.We propose a deep Monte Carlo Tree Search(MCTS)-based intelligent Pilot-power Allocation Scheme(iPAS)to address this issue.The core of iPAS is a multi-task deep reinforcement learning algorithm that can automatically learn the radio environment and make decisions on the pilot sequence and power allocation to maximize the spectrum efficiency with self-play training.To accelerate the searching convergence,we introduce a Deep Neural Network(DNN)to predict the pilot sequence and power allocation actions.The DNN is trained in a self-supervised learning manner,where the training data is generated from the searching process of the MCTS algorithm.Numerical results show that our proposed iPAS achieves a better Cumulative Distribution Function(CDF)of the ergodic spectral efficiency compared with the previous suboptimal algorithms. 展开更多
关键词 Massive MIMO pilot contamination pilot and power jointly allocation Deep self-supervised learning
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运用ProtectionPilot保护医院局域网
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作者 夏舜 卢爱玲 危小健 《中医药管理杂志》 2010年第7期663-664,共2页
文章详细介绍了针对当前医院使用的由为数众多的计算机构成的各种网络,以及运用ProtectionPilot来统一部署杀毒软件McAfee VirusScan Enterprise 8.5i,进而充分发挥McAfee系列产品的强大安全防护功能,保护整个医院局域网系统的安全。
关键词 PROTECTION pilot MCAFEE VIRUSSCAN ENTERPRISE 8.5i 医院局域网
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A Pilot Contamination Avoidance Based on Pilot Pattern Design for Ultra-Dense Network
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作者 Jie Huang Fan Yang +2 位作者 Yiwen Gao Zhiming Wang Jun Zhong 《China Communications》 SCIE CSCD 2020年第12期235-246,共12页
With the ever-growing number of base stations(BSs)and user equipments(UEs)in ultra-dense networks(UDN),reusing the same pilot sequences among the cells is inevitable.With pilot reuse scheme,the channel estimation obta... With the ever-growing number of base stations(BSs)and user equipments(UEs)in ultra-dense networks(UDN),reusing the same pilot sequences among the cells is inevitable.With pilot reuse scheme,the channel estimation obtained at a BS contains not only the desired channel-state information(CSI)but also interference from neighboring cells,which can severely degrade CSI estimation performance and adversely affect communication performance.In this paper we consider a pilot contamination avoidance based on pilot pattern design for UDN where the pilot reuse employed and the interfering users from neighboring cells may be not at lower power levels at the BS compared to the in-cell users.We present a novel statistical interference model of sub-carriers to describe the non-deterministic interference from neighboring cells.Then,we provide a pilot pattern design model with non-uniform pilot distribution.Based on this,a pilot contamination avoidance based on pilot pattern design is proposed where pilot reuse scheme and the non-deterministic interference from neighboring cells are taken into consideration.Unlike existing interference mitigation approaches,the proposed method eliminates interference through the method of interference avoidance and can be applied to different kinds of channel estimation algorithms.Simulation results showed that the proposed approach can effectively avoid the interference and ensure the accuracy of channel estimation. 展开更多
关键词 ultra-dense networks(UDN) pilot reuse interference avoidance pilot pattern design
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采用color—pilot颜色校正软件校正比色片数码照片并分析其在CIEL*a*b*色度空间中的位置变化 被引量:1
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作者 贺专 段嫄嫄 +5 位作者 沈丽娟 董潇 曾智惠 郭秋云 董瑜 贾骏 《牙体牙髓牙周病学杂志》 CAS 北大核心 2012年第12期705-708,共4页
目的:采用color-pilot颜色校正软件校正比色片数码照片并分析其在色度空间中的位置变化。方法:采用Vita 3D Master比色板作为试件,在诊室内拍摄比色片数码照片,并运用color-pilot颜色校正软件进行校正,最后与暗箱内拍摄的相应比色片数... 目的:采用color-pilot颜色校正软件校正比色片数码照片并分析其在色度空间中的位置变化。方法:采用Vita 3D Master比色板作为试件,在诊室内拍摄比色片数码照片,并运用color-pilot颜色校正软件进行校正,最后与暗箱内拍摄的相应比色片数码照片进行对比。结果:比较诊室内与暗箱内拍摄的比色片数码照片,发现两组照片L*值之间、a*值之间差异明显(P<0.05),b*值之间则无明显差异(P>0.05);运用color-pilot颜色校正软件校正诊室内拍摄的数码照片后,发现两组照片L*值之间的差异仍然存在(P<0.05),但差异缩小(较诊室内拍摄的数码照片,校正后的数码照片L*值更接近于暗箱内拍摄的数码照片L*值),而a*值之间无明显差异(P>0.05),b*值之间依然无明显差异(P>0.05)。二者在色度空间中的位置也较校正前更为靠近。计算暗箱内、诊室内、校正后3组照片的ΔE值发现,校正后与暗箱内数码照片此值最小。结论:color-pilot颜色校正软件校正比色片数码照片后,可以在一定程度上减小数码照片的色彩偏差。 展开更多
关键词 数码照片 color—pilot CIEL*a*b*色度空间 色差
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联合循环前缀和Pilot的OFDM系统定时同步方法 被引量:3
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作者 毛雪鸿 周武旸 《中国科学技术大学学报》 CAS CSCD 北大核心 2006年第8期818-821,892,共5页
提出了一种联合循环前缀和Pilot的定时同步方法,并将其用于高速传输的无线移动正交频分复用(OFDM)系统.算法首先利用循环前缀定时函数得到时偏的估计范围,然后在估计范围内利用导频定时函数得到时偏的精确估计.由于不需要加入训练序列,... 提出了一种联合循环前缀和Pilot的定时同步方法,并将其用于高速传输的无线移动正交频分复用(OFDM)系统.算法首先利用循环前缀定时函数得到时偏的估计范围,然后在估计范围内利用导频定时函数得到时偏的精确估计.由于不需要加入训练序列,提出的定时同步方法最大限度地节省了系统开销,提高了系统的频带利用率,而且利用导频序列进行定时同步可以有效地克服符号间干扰的影响.仿真结果表明,该算法能够改进时频估计在多径信道下的精度,提高系统在多径衰落信道下的性能. 展开更多
关键词 OFDM 定时同步 循环前缀 pilot 多径衰落信道
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Nitrogen and phosphorus removal in pilot-scale anaerobic-anoxic oxidation ditch system 被引量:35
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作者 PENG Yongzhen HOU Hongxun +2 位作者 WANG Shuying CUI Youwei Zhiguo Yuan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期398-403,共6页
To achieve high efficiency of nitrogen and phosphorus removal and to investigate the rule of simultaneous nitrification and denitrification phosphorus removal (SNDPR), a whole course of SNDPR damage and recovery was... To achieve high efficiency of nitrogen and phosphorus removal and to investigate the rule of simultaneous nitrification and denitrification phosphorus removal (SNDPR), a whole course of SNDPR damage and recovery was studied in a pilot-scale, anaerobicanoxic oxidation ditch (OD), where the volumes of anaerobic zone, anoxic zone, and ditches zone of the OD system were 7, 21, and 280 L, respectively. The reactor was fed with municipal wastewater with a flow rate of 336 L/d. The concept of simultaneous nitrification and denitrification (SND) rate (rSND) was put forward to quantify SND. The results indicate that: (1) high nitrogen and phosphorus removal efficiencies were achieved during the stable SND phase, total nitrogen (TN) and total phosphate (TP) removal rates were 80% and 85%, respectively; (2) when the system was aerated excessively, the stability of SND was damaged, and rSND dropped from 80% to 20% or less; (3) the natural logarithm of the ratio of NOx to NH4^+ in the effluent had a linear correlation to oxidation-reduction potential (ORP); (4) when NO3^- was less than 6 mg/L, high phosphorus removal efficiency could be achieved; (5) denitrifying phosphorus removal (DNPR) could take place in the anaerobic-anoxic OD system. The major innovation was that the SND rate was devised and quantified. 展开更多
关键词 oxidation ditch biological nitrogen removal biological phosphorus removal simultaneous nitrification and denitrification (SND) pilot scale municipal wastewater
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