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Federated Learning Model for Auto Insurance Rate Setting Based on Tweedie Distribution 被引量:1
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作者 Tao Yin Changgen Peng +2 位作者 Weijie Tan Dequan Xu Hanlin Tang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期827-843,共17页
In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining ... In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining the Tweedie regression model involves training on a centralized dataset,when the data is provided by multiple parties,training a privacy-preserving Tweedie regression model without exchanging raw data becomes a challenge.To address this issue,this study introduces a novel vertical federated learning-based Tweedie regression algorithm for multi-party auto insurance rate setting in data silos.The algorithm can keep sensitive data locally and uses privacy-preserving techniques to achieve intersection operations between the two parties holding the data.After determining which entities are shared,the participants train the model locally using the shared entity data to obtain the local generalized linear model intermediate parameters.The homomorphic encryption algorithms are introduced to interact with and update the model intermediate parameters to collaboratively complete the joint training of the car insurance rate-setting model.Performance tests on two publicly available datasets show that the proposed federated Tweedie regression algorithm can effectively generate Tweedie regression models that leverage the value of data fromboth partieswithout exchanging data.The assessment results of the scheme approach those of the Tweedie regressionmodel learned fromcentralized data,and outperformthe Tweedie regressionmodel learned independently by a single party. 展开更多
关键词 Rate setting Tweedie distribution generalized linear models federated learning homomorphic encryption
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Construction of a Computational Scheme for the Fuzzy HIV/AIDS Epidemic Model with a Nonlinear Saturated Incidence Rate 被引量:1
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作者 Muhammad Shoaib Arif Kamaleldin Abodayeh Yasir Nawaz 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1405-1425,共21页
This work aimed to construct an epidemic model with fuzzy parameters.Since the classical epidemic model doesnot elaborate on the successful interaction of susceptible and infective people,the constructed fuzzy epidemi... This work aimed to construct an epidemic model with fuzzy parameters.Since the classical epidemic model doesnot elaborate on the successful interaction of susceptible and infective people,the constructed fuzzy epidemicmodel discusses the more detailed versions of the interactions between infective and susceptible people.Thenext-generation matrix approach is employed to find the reproduction number of a deterministic model.Thesensitivity analysis and local stability analysis of the systemare also provided.For solving the fuzzy epidemic model,a numerical scheme is constructed which consists of three time levels.The numerical scheme has an advantage overthe existing forward Euler scheme for determining the conditions of getting the positive solution.The establishedscheme also has an advantage over existing non-standard finite difference methods in terms of order of accuracy.The stability of the scheme for the considered fuzzy model is also provided.From the plotted results,it can beobserved that susceptible people decay by rising interaction parameters. 展开更多
关键词 Epidemic model fuzzy rate parameters next generation matrix local stability proposed numerical scheme
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Amend:An integrated platform of retracted papers and concerned papers
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作者 Menghui Li Fuyou Chen +2 位作者 Sichao Tong Liying Yang Zhesi Shen 《Journal of Data and Information Science》 CSCD 2024年第2期41-55,共15页
Purpose:The notable increase in retraction papers has attracted considerable attention from diverse stakeholders.Various sources are now offering information related to research integrity,including concerns voiced on ... Purpose:The notable increase in retraction papers has attracted considerable attention from diverse stakeholders.Various sources are now offering information related to research integrity,including concerns voiced on social media,disclosed lists of paper mills,and retraction notices accessible through journal websites.However,despite the availability of such resources,there remains a lack of a unified platform to consolidate this information,thereby hindering efficient searching and cross-referencing.Thus,it is imperative to develop a comprehensive platform for retracted papers and related concerns.This article aims to introduce“Amend,”a platform designed to integrate information on research integrity from diverse sources.Design/methodology/approach:The Amend platform consolidates concerns and lists of problematic articles sourced from social media platforms(e.g.,PubPeer,For Better Science),retraction notices from journal websites,and citation databases(e.g.,Web of Science,CrossRef).Moreover,Amend includes investigation and punishment announcements released by administrative agencies(e.g.,NSFC,MOE,MOST,CAS).Each related paper is marked and can be traced back to its information source via a provided link.Furthermore,the Amend database incorporates various attributes of retracted articles,including citation topics,funding details,open access status,and more.The reasons for retraction are identified and classified as either academic misconduct or honest errors,with detailed subcategories provided for further clarity.Findings:Within the Amend platform,a total of 32,515 retracted papers indexed in SCI,SSCI,and ESCI between 1980 and 2023 were identified.Of these,26,620(81.87%)were associated with academic misconduct.The retraction rate stands at 6.64 per 10,000 articles.Notably,the retraction rate for non-gold open access articles significantly differs from that for gold open access articles,with this disparity progressively widening over the years.Furthermore,the reasons for retractions have shifted from traditional individual behaviors like falsification,fabrication,plagiarism,and duplication to more organized large-scale fraudulent practices,including Paper Mills,Fake Peer-review,and Artificial Intelligence Generated Content(AIGC).Research limitations:The Amend platform may not fully capture all retracted and concerning papers,thereby impacting its comprehensiveness.Additionally,inaccuracies in retraction notices may lead to errors in tagged reasons.Practical implications:Amend provides an integrated platform for stakeholders to enhance monitoring,analysis,and research on academic misconduct issues.Ultimately,the Amend database can contribute to upholding scientific integrity.Originality/value:This study introduces a globally integrated platform for retracted and concerning papers,along with a preliminary analysis of the evolutionary trends in retracted papers. 展开更多
关键词 Research Integrity Retraction Rate Academic Misconduct Reasons for Retraction Temporal Trends
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Covert Communication in Integrated High Altitude Platform Station Terrestrial Networks
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作者 Zeke Wu Kefeng Guo +1 位作者 Rui Liu Shibin Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期583-598,共16页
In recent years,Internet of Things(IoT)technology has emerged and gradually sprung up.As the needs of largescale IoT applications cannot be satisfied by the fifth generation(5G)network,wireless communication network n... In recent years,Internet of Things(IoT)technology has emerged and gradually sprung up.As the needs of largescale IoT applications cannot be satisfied by the fifth generation(5G)network,wireless communication network needs to be developed into the sixth generation(6G)network.However,with the increasingly prominent security problems of wireless communication networks such as 6G,covert communication has been recognized as one of the most promising solutions.Covert communication can realize the transmission of hidden information between both sides of communication to a certain extent,which makes the transmission content and transmission behavior challenging to be detected by noncooperative eavesdroppers.In addition,the integrated high altitude platform station(HAPS)terrestrial network is considered a promising development direction because of its flexibility and scalability.Based on the above facts,this article investigates the covert communication in an integrated HAPS terrestrial network,where a constant power auxiliary node is utilized to send artificial noise(AN)to realize the covert communication.Specifically,the covert constraint relationship between the transmitting and auxiliary nodes is derived.Moreover,the closed-form expressions of outage probability(OP)and effective covert communication rate are obtained.Finally,numerical results are provided to verify our analysis and reveal the impacts of critical parameters on the system performance. 展开更多
关键词 Covert communication the integrated HAPS terrestrial network constant power auxiliary node artificial noise(AN) effective covert communication rate
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Effects of transient temperature gradient on frost heave of saturated silty clay in an open system
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作者 HongYan Ma YuanFang Cui +2 位作者 JianQiao Zhang Song Li Song Xu 《Research in Cold and Arid Regions》 CSCD 2023年第6期268-277,共10页
Frost heave in seasonally frozen regions is a one-dimensional process that could severely damage infrastructure subgrades.Stress state,temperature and water migration are important factors for frost heave.This work in... Frost heave in seasonally frozen regions is a one-dimensional process that could severely damage infrastructure subgrades.Stress state,temperature and water migration are important factors for frost heave.This work investigated the effects of soil temperature and volumetric water content on the transient frost heave ratio during the freezing of saturated silty clay in an open system and analyzed the relationships between the transient frost heave ratio and freezing rate and between temperature gradient and frost heave rate.The results show that the frost heave ratio,frost heave rate,and freezing rate are positively correlated with the temperature gradient since the temperature gradient drives the water migration during freezing,indicating the transient temperature gradient could be used to evaluate the frost heave of saturated silty clay.The transient freezing rate and transient frost heave ratio are logarithmically related to the transient frost heave ratio and transient temperature gradient,respectively.The effects of transient temperature gradient on frost heave are the principal mechanism responsible for different frost heave characteristics and uneven frost heave along a subgrade of the same soil type. 展开更多
关键词 Saturated silty clay Frost heave Transient temperature gradient Frost heave ratio Frost heave rate
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Intrusion Detection Using Federated Learning for Computing
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作者 R.S.Aashmi T.Jaya 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1295-1308,共14页
The integration of clusters,grids,clouds,edges and other computing platforms result in contemporary technology of jungle computing.This novel technique has the aptitude to tackle high performance computation systems a... The integration of clusters,grids,clouds,edges and other computing platforms result in contemporary technology of jungle computing.This novel technique has the aptitude to tackle high performance computation systems and it manages the usage of all computing platforms at a time.Federated learning is a collaborative machine learning approach without centralized training data.The proposed system effectively detects the intrusion attack without human intervention and subsequently detects anomalous deviations in device communication behavior,potentially caused by malicious adversaries and it can emerge with new and unknown attacks.The main objective is to learn overall behavior of an intruder while performing attacks to the assumed target service.Moreover,the updated system model is send to the centralized server in jungle computing,to detect their pattern.Federated learning greatly helps the machine to study the type of attack from each device and this technique paves a way to complete dominion over all malicious behaviors.In our proposed work,we have implemented an intrusion detection system that has high accuracy,low False Positive Rate(FPR)scalable,and versatile for the jungle computing environment.The execution time taken to complete a round is less than two seconds,with an accuracy rate of 96%. 展开更多
关键词 Jungle computing high performance computation federated learning false positive rate intrusion detection system(IDS)
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Adaptive Retransmission Design for Wireless Federated Edge Learning
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作者 XU Xinyi LIU Shengli YU Guanding 《ZTE Communications》 2023年第1期3-14,共12页
As a popular distributed machine learning framework,wireless federated edge learning(FEEL)can keep original data local,while uploading model training updates to protect privacy and prevent data silos.However,since wir... As a popular distributed machine learning framework,wireless federated edge learning(FEEL)can keep original data local,while uploading model training updates to protect privacy and prevent data silos.However,since wireless channels are usually unreliable,there is no guarantee that the model updates uploaded by local devices are correct,thus greatly degrading the performance of the wireless FEEL.Conventional retransmission schemes designed for wireless systems generally aim to maximize the system throughput or minimize the packet error rate,which is not suitable for the FEEL system.A novel retransmission scheme is proposed for the FEEL system to make a tradeoff between model training accuracy and retransmission latency.In the proposed scheme,a retransmission device selection criterion is first designed based on the channel condition,the number of local data,and the importance of model updates.In addition,we design the air interface signaling under this retransmission scheme to facilitate the implementation of the proposed scheme in practical scenarios.Finally,the effectiveness of the proposed retransmission scheme is validated through simulation experiments. 展开更多
关键词 federated edge learning RETRANSMISSION unreliable communication convergence rate retransmission latency
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Analysis of the Implementation of Integrated Healthcare Management in Preoperative Preparation
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作者 Huiling Liu Xuling Li +3 位作者 Xinyi Liu Yuhua Ma Haomin Li Cuiqing Liu 《Journal of Clinical and Nursing Research》 2023年第3期138-142,共5页
Objective:To strengthen preoperative preparation management and reduce preoperative preparation defects.Methods:We set up a special medical care management team to investigate the preoperative preparation in surgical ... Objective:To strengthen preoperative preparation management and reduce preoperative preparation defects.Methods:We set up a special medical care management team to investigate the preoperative preparation in surgical departments,analyze the causes of the shortcomings in preoperative preparation,and propose countermeasures.The medical staff jointly formulated plans related to preoperative preparation management including clear outline of responsibilities,strengthening of training,integrated medical care,timely feedback,and continuous improvement.Besides,the preoperative preparation of patients before and after the improvement measures were compared using statistical analysis.Results:The rate of inadequate preoperative preparation was 11.14 per thousand before the integrated management model was implemented.After the implementation of the integrated management model,the rate of inadequate preoperative preparation decreased to 2.99 per thousand,and the difference was statistically(P<0.05).Conclusion:The integrated management of preoperative preparation can help reduce the rate of preoperative complications and ensure the safety of surgery. 展开更多
关键词 Integrated healthcare Preoperative preparation Rate of inadequate preoperative preparation
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Dynamic behaviors of water-saturated and frozen sandstone subjected to freeze-thaw cycles
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作者 Feng Gao Cong Li +2 位作者 Xin Xiong Yanan Zhang Keping Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1476-1490,共15页
In high-altitude cold areas,freeze-thaw(F-T)cycles induced by day-night and seasonal temperature changes cause numerous rock mass slope engineering disasters.To investigate the dynamic properties of rock in the natura... In high-altitude cold areas,freeze-thaw(F-T)cycles induced by day-night and seasonal temperature changes cause numerous rock mass slope engineering disasters.To investigate the dynamic properties of rock in the natural environment of a high-altitude cold area,standard specimens were drilled from the slope of the Jiama copper mine in Tibet,and dynamic compression tests were performed on watersaturated and frozen sandstone with different numbers of F-T cycles(0,10,20,30,and 40)by the split Hopkinson pressure bar(SHPB)system with a cryogenic control system.The influence of water-saturated and frozen conditions on the dynamic performance of sandstone was investigated.The following conclusions are drawn:(1)With increasing strain rate,the attenuation factor(la)of water-saturated sandstone and the intensifying factor(li)of frozen sandstone linearly increase.As the number of F-T cycles increases,the dependence factor(ld)of water-saturated sandstone linearly decreases,whereas the ld of frozen sandstone linearly increases.(2)The prediction equation of the dynamic compressive strength of water-saturated and frozen sandstone is obtained,which can be used to predict the dynamic compressive strength of sandstone after various F-T cycles based on the strain rate.(3)The mesoscopic mechanism of water-saturated and frozen sandstone’s dynamic compressive strength evolution is investigated.The water softening effect causes the dynamic compressive strength of water-saturated sandstone to decrease,whereas the strengthening effect of pore ice causes it to increase.(4)The decrease in the relative dynamic compressive strength of water-saturated sandstone and the increase in the relative dynamic compressive strength of frozen sandstone can be attributed to the increased porosity. 展开更多
关键词 Freeze-thaw(F-T)cycle damage Dynamic properties Split Hopkinson pressure bar(SHPB) Increasing rate of porosity
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Parallel Integrated Model-Driven and Data-Driven Online Transient Stability Assessment Method for Power System
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作者 Ying Zhang Xiaoqing Han +3 位作者 Chao Zhang Ying Qu Yang Liu Gengwu Zhang 《Energy Engineering》 EI 2023年第11期2585-2609,共25页
More and more uncertain factors in power systems and more and more complex operation modes of power systems put forward higher requirements for online transient stability assessment methods.The traditional modeldriven... More and more uncertain factors in power systems and more and more complex operation modes of power systems put forward higher requirements for online transient stability assessment methods.The traditional modeldriven methods have clear physical mechanisms and reliable evaluation results but the calculation process is time-consuming,while the data-driven methods have the strong fitting ability and fast calculation speed but the evaluation results lack interpretation.Therefore,it is a future development trend of transient stability assessment methods to combine these two kinds of methods.In this paper,the rate of change of the kinetic energy method is used to calculate the transient stability in the model-driven stage,and the support vector machine and extreme learning machine with different internal principles are respectively used to predict the transient stability in the data-driven stage.In order to quantify the credibility level of the data-driven methods,the credibility index of the output results is proposed.Then the switching function controlling whether the rate of change of the kinetic energy method is activated or not is established based on this index.Thus,a newparallel integratedmodel-driven and datadriven online transient stability assessment method is proposed.The accuracy,efficiency,and adaptability of the proposed method are verified by numerical examples. 展开更多
关键词 Rate of change of kinetic energy support vectormachine extreme learning machine credibility index model-data parallel integration
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Enhanced Reconfigurable Intelligent Surface Assisted mmWave Communication: A Federated Learning 被引量:7
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作者 Lixin Li Donghui Ma +4 位作者 Huan Ren Dawei Wang Xiao Tang Wei Liang Tong Bai 《China Communications》 SCIE CSCD 2020年第10期115-128,共14页
Reconfigurable intelligent surface(RIS)has been proposed as a potential solution to improve the coverage and spectrum efficiency for future wireless communication.However,the privacy of users’data is often ignored in... Reconfigurable intelligent surface(RIS)has been proposed as a potential solution to improve the coverage and spectrum efficiency for future wireless communication.However,the privacy of users’data is often ignored in previous works,such as the user’s location information during channel estimation.In this paper,we propose a privacy-preserving design paradigm combining federated learning(FL)with RIS in the mmWave communication system.Based on FL,the local models are trained and encrypted using the private data managed on each local device.Following this,a global model is generated by aggregating them at the central server.The optimal model is trained for establishing the mapping function between channel state information(CSI)and RIS’configuration matrix in order to maximize the achievable rate of the received signal.Simulation results demonstrate that the proposed scheme can effectively approach to the theoretical value generated by centralized machine learning(ML),while protecting user’privacy. 展开更多
关键词 reconfigurable intelligent surface PRIVACY federated learning achievable rate
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Impact of stretching-segment on saturated flow rate of signalized intersection using cellular automation 被引量:4
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作者 李岩 陈宽民 过秀成 《Journal of Central South University》 SCIE EI CAS 2013年第10期2887-2896,共10页
In order to analyze the impact of stretching-segment on the saturated flow rate of signalized intersection approach, an improved cellular automation model was proposed to estimate its saturated flow rate. The NaSch mo... In order to analyze the impact of stretching-segment on the saturated flow rate of signalized intersection approach, an improved cellular automation model was proposed to estimate its saturated flow rate. The NaSch model was improved by adding different slow probabilities, turning deceleration rules and modified lane changing rules. The relationship between the saturated flow rate of stretching-segments and adjacent lanes was tested in numerical simulation. The length of stretching-segment, cycle length and green time were selected as impact factors of the cellular automation model. The simulation result indicates that the geometrics design of stretching-segment and the traffic signal timing scenario have major effects on the saturated flow rate of the intersection approach. The saturated flow rate will continually increase with increasing stretching-segment length until it reaches a threshold. After reaching the threshold, the stretching-segment can be treated as a separate lane. The green time is approximately linearly related to the threshold length of the stretching-segment. An optimum cycle length exists when the length of the stretching-segment is not long enough, and it is approximately linearly related to the length of stretching-segment. 展开更多
关键词 traffic engineering saturated flow rate stretching-segment cellular automation model
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Sessile serrated adenoma detection rate is correlated with adenoma detection rate 被引量:2
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作者 Daisuke Ohki Yosuke Tsuji +15 位作者 Tomohiro Shinozaki Yoshiki Sakaguchi Chihiro Minatsuki Hiroto Kinoshita Keiko Niimi Satoshi Ono Yoku Hayakawa Shuntaro Yoshida Atsuo Yamada Shinya Kodashima Nobutake Yamamichi Yoshihiro Hirata Tetsuo Ushiku Mitsuhiro Fujishiro Masashi Fukayama Kazuhiko Koike 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2018年第3期82-90,共9页
AIM To investigated the association between adenoma detection rate(ADR) and sessile serrated ADR(SSADR) and significant predictors for sessile serrated adenomas(SSA) detection.METHODS This study is a retrospective, si... AIM To investigated the association between adenoma detection rate(ADR) and sessile serrated ADR(SSADR) and significant predictors for sessile serrated adenomas(SSA) detection.METHODS This study is a retrospective, single-center analysis. Total colonoscopies performed by the gastroenterologists at the University of Tokyo Hospital between January and December 2014 were retrospectively identified. Polyps were classified as low-grade or high-grade adenoma, cancer, SSA, or SSA with cytological dysplasia, and the prevalence of each type of polyp was investigated. Predictors of adenoma and SSA detection were examined using logistic generalized estimating equation models. The association between ADR and SSADR for each gastroenterologist was investigated by calculating a correlation coefficient weighted by the number of each gastroenterologist's examination.RESULTS A total of 3691 colonoscopies performed by 35 gastroenterologists were assessed. Overall, 978 (26.5%) low-and 84 (2.2%) high-grade adenomas, 81 (2.2%) cancers, 66 (1.8%) SSAs, and 2 (0.1%) SSAs with cytological dysplasia were detected. Overall ADR was 29.5%(men 33.2%, women 23.8%) and overall SSADR was 1.8%(men 1.7%, women 2.1%). In addition, 672 low-grade adenomas (68.8% of all the detected lowgrade adenomas), 58 (69.9%) high-grade adenomas, 29 (34.5%) cancers, 52 (78.8%) SSAs, and 2 (100%) SSAs with cytological dysplasia were found in the proximal colon. Adenoma detection was the only significant predictor of SSA detection (adjusted OR: 2.53, 95%CI: 1.53-4.20; P < 0.001). The correlation coefficient between ADR and SSADR weighted by the number of each gastroenterologist's examinations was 0.606(P < 0.001).CONCLUSION Our results demonstrated that ADR is correlated to SSADR. In addition, patients with adenomas had a higher prevalence of SSAs than those without adenomas. 展开更多
关键词 Sessile serrated ADENOMA Sessile serrated ADENOMA DETECTION RATE ADENOMA DETECTION RATE COLONOSCOPY Interval COLORECTAL cancer
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Interendoscopist variability in proximal colon polyp detection is twice higher for serrated polyps than adenomas 被引量:2
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作者 Jean-François Bretagne Stéphanie Hamonic +2 位作者 Christine Piette Jean-François Viel Guillaume Bouguen 《World Journal of Gastroenterology》 SCIE CAS 2016年第38期8549-8557,共9页
AIM To assess the interendoscopist variability in the detection of colorectal polyps according to their location and histological type.METHODS This study was a retrospective analysis of prospectively collected data fr... AIM To assess the interendoscopist variability in the detection of colorectal polyps according to their location and histological type.METHODS This study was a retrospective analysis of prospectively collected data from a regional colorectal cancer(CRC) screening program; 2979 complete colonoscopies from 18 endoscopists were included. Variability in performance between endoscopists for detection of at least one adenoma(A), one proximal adenoma(PA), one distal adenoma(DA), and one proximal serrated polyp(PSP) was assessed by using multilevel logistic regression models.RESULTS The observed detection rates among the 18 endoscopists ranged from 24.6% to 47.6%(mean = 35.7%) for A, from 19.1% to 39.0%(mean = 29.4%) for DA, from 6.0% to 22.9%(mean = 12.4%) for PA, and from 1.3% to 19.3%(mean = 6.9%) for PSP.After adjusting for patient-level variables(sex, age), the interendoscopist detection rates variability achieved a significant level for A, PA, and PSP but not for DA(P = 0.03, P = 0.02, P = 0.02 and P = 0.08, respectively). This heterogeneity, as measured by the variance partition coefficient, was approximately threefold higher for PA(6.6%) compared with A(2.1%), and twofold higher for PSP(12.3%) compared with PA.CONCLUSION These results demonstrate significant interendoscopist variability for proximal polyp particularly for serrated p o l y p s, b u t n o t f o r d i s t a l a d e n o m a d e t e c t i o n. These findings contribute to explain the decreased effectiveness of complete colonoscopies at preventing proximal CRCs and the need to carefully assess the proximal colon during scope procedure. 展开更多
关键词 COLONOSCOPY Colorectal cancer ADENOMA Serrated POLYP PROXIMAL POLYP DETECTION rate Quality performance
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The Causes of Conversion from Laparoscopy to Laparotomy in Patients with Laparoscopic Repair of Perforated Peptic Ulcer 被引量:4
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作者 Chien-Hua Lin Der-Ao Chou +1 位作者 Yueh-Tsung Lee Hurng-Sheng Wu 《Surgical Science》 2015年第2期75-79,共5页
Purpose: Perforated peptic ulcer is an emergency condition. Laparoscopic ulcer repair is a feasible and safe procedure. The aim of this study was to research the efficacy of laparoscopic repair of peptic ulcer and to ... Purpose: Perforated peptic ulcer is an emergency condition. Laparoscopic ulcer repair is a feasible and safe procedure. The aim of this study was to research the efficacy of laparoscopic repair of peptic ulcer and to discuss the causes of conversion from laparoscopy to laparotomy. Methods: We collected 34 patients with perforated peptic ulcer underwent laparoscopic surgery from October 2003 to October 2008. Thirty four patients with perforated peptic ulcer underwent laparoscopic intervention and 6 cases were converted to laparotomy. The demographics, laboratory data, perioperative data, morbidity and mortality were compared. Results: In demographics of two groups, there were no significant differences in sex, age, location, and mean duration of symptoms of acute abdominal pain. However, there were significant differences in median size of perforation, mean duration of history of peptic ulcer related pain, and the experiences of surgeon. There were no significant differences in the laboratory data and perioperative data of two groups. In morbidity?and mortality of two groups, there were no significant differences in leakage, wound infection, intra-abdominal abscess, ileus, urinary tract infection, pneumonia, and mortality, but there was significant difference in overall morbidity in two groups. Conclusions: Laparoscopic repair of perforated peptic ulcer is safe and could be used in routine clinical practice. However, patients with larger perforations (>10 mm), longer duration of history peptic ulcer related pain (>2 years), and learning curve of surgeon could be associated with conversion rate. It is associated with higher morbidity in patients with conversion from laparoscopy to laparotomy. 展开更多
关键词 LAPAROSCOPY Perforated PEPTIC ULCER Repair CONVERSION Rate
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Intensity modulated radiation therapy with simultaneous integrated boost based dose escalation on neoadjuvant chemoradiation therapy for locally advanced distal esophageal adenocarcinoma 被引量:1
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作者 Ming Zeng Fernando N Aguila +4 位作者 Taral Patel Mark Knapp XueQiang Zhu XiLin Chen Phillip D Price 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2016年第5期474-480,共7页
AIM:To evaluate impact of radiation therapy dose escalation through intensity modulated radiation therapy with simultaneous integrated boost(IMRT-SIB).METHODS:We retrospectively reviewed the patients who underwent fou... AIM:To evaluate impact of radiation therapy dose escalation through intensity modulated radiation therapy with simultaneous integrated boost(IMRT-SIB).METHODS:We retrospectively reviewed the patients who underwent four-dimensional-based IMRT-SIBbased neoadjuvant chemoradiation protocol.During the concurrent chemoradiation therapy,radiation therapy was through IMRT-SIB delivered in 28 consecutive daily fractions with total radiation doses of 56 Gy to tumor and 5040 Gy dose-painted to clinical tumor volume,with a regimen at the discretion of the treating medical oncologist.This was followed by surgical tumor resection.We analyzed pathological completion response(p CR) rates its relationship with overall survival and event-freesurvival.RESULTS:Seventeen patients underwent dose escalation with the IMRT-SIB protocol between 2007 and 2014 and their records were available for analysis.Among the IMRT-SIB-treated patients,the toxicity appeared mild,the most common side effects were grade 1-3 esophagitis(46%) and pneumonitis(11.7%).There were no cardiac events.The Ro resection rate was 94%(n = 16),the p CR rate was 47%(n = 8),and the postoperative morbidity was zero.There was one mediastinal failure found,one patient had local failure at the anastomosis site,and the majority of failures were distant in the lung or bone.The 3-year diseasefree survival and overall survival rates were 41%(n = 7) and 53%(n = 9),respectively.CONCLUSION:The dose escalation through IMRT-SIB in the chemoradiation regimen seems responsible for down-staging the distal esophageal with well-tolerated complications. 展开更多
关键词 Intensity modulated radiation therapy ESOPHAGEAL ADENOCARCINOMA Simultaneous integrated boost NEOADJUVANT CHEMORADIATION Dose ESCALATION Resection rate
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Preparation of New Cementitious System using Fly Ash and Dehydrated Autoclaved Aerated Concrete 被引量:3
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作者 水中和 LU Jianxin +2 位作者 TIAN Sufang SHEN Peiliang DING Sha 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期726-732,共7页
We experimentally studied the interaction between pozzolanic material(fly ash) and dehydrated autoclaved aerated concrete(DAAC). The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner ... We experimentally studied the interaction between pozzolanic material(fly ash) and dehydrated autoclaved aerated concrete(DAAC). The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner than 75μm and was then heated to temperatures up to 900 ℃. New cementitious material was prepared by proportioning fly ash and DAAC, named as AF. X-ray diffraction(XRD) was employed to identify the crystalline phases of DAAC before and after rehydration. The hydration process of AF was analyzed by the heat of hydration and non-evaporable water content(Wn). The experimental results show that the highest reactivity of DAAC can be obtained by calcining the powder at 700 ℃ and the dehydrated products are mainly β-C2 S and CaO. The cumulative heat of hydration and Wn was found to be strongly dependent on the replacement level of fl y ash, increasing the replacement level of fl y ash lowered them in AF. The strength contribution rates on pozzolanic effect of fl y ash in AF are always negative, showing a contrary tendency of that of cement-fl y ash system. 展开更多
关键词 dehydrated autoclaved aerated concrete pozzolanic reaction heat of hydration nonevaporable water content strength contribution rate
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Stability Analysis of SIQS Epidemic Model with Saturated Incidence Rate 被引量:1
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作者 O. Adebimpe L. M. Erinle-Ibrahim A. F. Adebisi 《Applied Mathematics》 2016年第10期1082-1086,共5页
A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium ... A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium exists when the basic reproduction number R0, is less or greater than unity respectively. The global stability of the disease-free and endemic equilibrium is proved using Lyapunov functions and Poincare-Bendixson theorem plus Dulac’s criterion respectively. 展开更多
关键词 SIQS Epidemic Model Saturated Incidence Rate Basic Reproduction Number Lyapunov Function Poincare-Bendixson Dulac Criterion
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The Mechanism of Critical Strain of Serrated Yielding in Strain Rate Domain
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作者 符师桦 蔡玉龙 +2 位作者 杨素丽 张青川 伍小平 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第2期79-82,共4页
The mechanism of the critical strain of serrated yielding is studied via tension tests at various strain rates. Betore the critical strain, it is deduced that dislocations are not pinned at high strain rates, and disl... The mechanism of the critical strain of serrated yielding is studied via tension tests at various strain rates. Betore the critical strain, it is deduced that dislocations are not pinned at high strain rates, and dislocations at low strain rates are pinned but cannot escape. The critical strain depends on the first pinning process at high strain rates and on the first unpinning process at low strain rates. The calculated results based on the two criteria are in good consistency with the experiment. 展开更多
关键词 of IS The Mechanism of Critical Strain of Serrated Yielding in Strain Rate Domain that RATE HIGH
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High-temperature Thermal Properties and Wear Behavior of Basalt as Heat Storage Material for Concentrated Solar Power Plants
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作者 廖峻 朱旭鹏 +3 位作者 LI Jianan XUE Shuwen ZOU Changwei 张军 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第4期547-553,共7页
The microstructures,components,thermal stability,specific heat capacity and thermal conductivity of basalt sample were studied.Besides,as a comprehensive result of thermal expansion and contraction process,both the fr... The microstructures,components,thermal stability,specific heat capacity and thermal conductivity of basalt sample were studied.Besides,as a comprehensive result of thermal expansion and contraction process,both the friction coefficient and wear rate of the basalt sample were also characterized.Our results indicate that basalt is an excellent candidate to be used as thermal energy storage material for concentrated solar power plants,and also provide a strategy for solar energy utilization in volcanic area with excellent geographical environment. 展开更多
关键词 thermal energy storage concentrated solar power BASALT wear rate
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