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Design and Digital Implementation of Controller for PMSM Using extended Kalman Filter

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Circuits and Systems 2013年第8期4卷 489-497页

作者： Mamatha Gowda Warsame H. Ali Penrose Cofie John Fuller Department of Electrical and Computer Engineering Prairie View A&M University Prairie View USA

A novel digital implementation of speed controller for a Permanent Magnet Synchronous Motor (PMSM) with disturbance rejection using conventional observer combined with extended Kalman Filter (EKF) is proposed. First, the EKF is constructed to achieve a precise estimation of the speed and current from the noisy measurement. Second, a proportional integral derivative (PID) controller is developed based on Linear Quadratic Regulator (LQR) to achieve speed command tracking performance. Then, an observer is designed and its error is utilized to provide load disturbance compensation. The proposed method greatly enhances the PMSM performance by reducing the control signal variation as well as the disturbance. The speed control performance is significantly improved compared to the case when we have an observer acting alone. The simulation results for the speed response and variation of the states when the PMSM is subjected to the load disturbance are presented. The results verify the effectiveness of the proposed method.

关键词： Permanent Magnet Synchronous Motor extended Kalman Filter PID Vector Control Observer

Energetic extended Edge Finding Filtering Algorithm for Cumulative Resource Constraints

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American Journal of Operations Research 2013年第6期3卷 589-600页

作者： Roger Kameugne Sévérine Betmbe Fetgo Laure Pauline Fotso Department of Computer Sciences Faculty of Sciences University of Yaounde I Yaoundé Cameroon Department of Mathematics Higher Teachers’ Training College University of Maroua Maroua Cameroon Department of Mathematics Faculty of Sciences University of Yaounde I Yaoundé Cameroon

Edge-finding and energetic reasoning are well known filtering rules used in constraint based disjunctive and cumulative scheduling during the propagation of the resource constraint. In practice, however, edge-finding is most used (because it has a low running time complexity) than the energetic reasoning which needs O(n3) time-intervals to be considered (where n is the number of tasks). In order to reduce the number of time-intervals in the energetic reasoning, the maximum density and the minimum slack notions are used as criteria to select the time-intervals. The paper proposes a new filtering algorithm for cumulative resource constraint, and titled energetic extended edge finder of complexity O(n3). The new algorithm is a hybridization of extended edge-finding and energetic reasoning: more powerful than the extended edge-finding and faster than the energetic reasoning. It is proven that the new algorithm subsumes the extended edge-finding algorithm. Results on Resource Constrained Project Scheduling Problems (RCPSP) from BL set and PSPLib librairies are reported. These results show that in practice the new algorithm is a good trade-off between the filtering power and the running time on instances where the number of tasks is less than 30.

关键词： Constraint-Based Scheduling Global Constraint Cumulative Resource Energetic Reasoning Edge-Finding extended Edge-Finding Maximum Density Minimum Slack

Adaptive extended Kalman Filtering for Bearings-Only Targets Tracking Problem

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Journal of Harbin Institute of Technology(New Series) 1998年第3期5卷 1-4页

作者：胡恒章周荻

An adaptive extended Kalman filtering (AEKF) is proposed for nonlinear control systems. For bearingsonly targets tracking problem, we present an adaptive extended Kalman filter which suits a nonlinear observation model and a linear dynamical model. Simulation results have shown that the adaptive extended Kalman filter for the passivetracking problem performs better than the original extended Kalman filter (EKF).

关键词： extended Kalman filtering adaptive extended Kalman filtering bearings-only targets tracking

Determinants of Long Acting Reversible Contraception Method Use among Mothers in extended Postpartum Period, Durame Town, Southern Ethiopia: A Cross Sectional Community Based Survey

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Health 2015年第10期7卷 1315-1326页

作者： Yirga Ewnetu Tamrie Ewenat Gebre Hanna Mesele Damte Argaw EngenderHealth Ethiopia Hawassa Ethiopia Addis Continental Institute of Public Health Addis Ababa Ethiopia Private Health Sector Program Addis Ababa Ethiopia

Background: After a live birth, there is much unsatisfied interest in, and unmet family planning need for contraception. Waiting at least for 24 months before attempting the next pregnancy was recommended to reduce the risk of adverse maternal, perinatal and infant outcomes. The purpose of this study was to assess the determinants of long acting reversible contraception method use among mothers in extended postpartum period in Durame Town, Southern Ethiopia. Methods: A community based cross sectional study was conducted in Durame Town, Southern Ethiopia in December, 2014. Systematic random sampling technique was employed to recruit a total 460 study participants. Structured and pretested questioner was used to collect the data. Descriptive statistics was employed to characterize the study population using frequencies and proportions. Bivariate logistic regression analysis was conducted to identify all possible factors affecting utilization of LARC method. Multivariable logistic regression model was developed to control the confounding variables. Adjusted Odds Ratio (AOR) with 95% Confidence Interval (CI) was computed in identifying the real factors associated with use of LARC methods. Results: In this study we found that the prevalence of LARC method use among mothers during their extended postpartum period was 36.7% (95%CI: 32.2, 41.0). The unmet family planning need of mothers in the extended postpartum period was 123 (27.9%). The odds of using LARC by literate mother were four fold higher than their counterpart illiterate mothers (AOR 4.09 95%CI: 1.68, 9.58, P value < 0.001). The odds of mother who had pervious experiences of using LARC were up to eight folds higher than mother never used LARC methods (AOR 7.84 95% CI: 3.78, 16.23, P value< 0.001). Mother who received counseling service on LARC methods during delivery was up to three times more likely to utilize the services than not counseled (AOR 3.29 95% CI: 1.53, 7.03, P value < 0.001). And odds of mothers wh

关键词： extended Postpartum Long Acting Reversible Contraception Method Use Determinants Ethiopia

Preoperative chemoradiation and extended pelvic lymphadenectomy for rectal cancer:Two distinct principles

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World Journal of Gastrointestinal Surgery 2010年第4期2卷 95-100页

作者： Tsuyoshi Konishi Toshiaki Watanabe Hirokazu Nagawa Masatoshi Oya Masashi Ueno Hiroya Kuroyanagi Yoshiya Fujimoto Takashi Akiyoshi Toshiharu Yamaguchi Tetsuichiro Muto Department of Gastroenterological Surgery Cancer Institute HospitalTokyo135-8550Japan Department of Surgical Oncology University of TokyoTokyo113-8655Japan Department of Surgery Teikyo University School of MedicineTokyo173-8605Japan

extended pelvic lymphadenectomy(EPL) with total mesorectal excision(TME) has been reported to provide oncological benefit in lower rectal cancer in *** Western countries EPL is not widely accepted because of frequent morbidity but instead preoperative chemoradiation(CRT) followed by TME has been established as a standard treatment for decreasing local ***,several studies have focused on the comparison between these two distinct therapeutic approaches in Western countries and Japan.A study comparing Dutch trial data and Japanese data revealed that EPL and RT are almost equivalent in decreasing local recurrence in lower rectal cancer as compared with TME *** that almost 45 survival can be achieved by EPL even in the presence of metastatic lateral lymph nodes(LLNs),EPL performed by experienced surgeons definitely contributes to decrease local *** the other hand,a randomized controlled trial in Japan that compared EPL with conventional TME following preoperative RT revealed that EPL is associated with a higher frequency of sexual and urinary dysfunction without oncological benefits in the presence of preoperative *** this point,preoperative CRT followed by conventional TME without EPL would be a better therapeutic approach in patients without evident metastatic *** future treatment,it would be desirable to have a narrower indication for EPL using full advantage of recent improvement in image *** objective comparison of these two principles between Japan and the West is difficult due to differences in patient groups,further studies would lead to the next great step towards future improvement in treating lower rectal cancer.

关键词： Rectal cancer extended lymphadenectomy Chemoradiation Pelvic lymph node Lateral lymph node

Residual Astigmatism Threshold and Patient Satisfaction with Bifocal, Trifocal and extended Range of Vision Intraocular Lenses (IOLs)

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Open Journal of Ophthalmology 2017年第1期7卷 1-7页

作者： Francesco Carones Carones Ophthalmology Center Milan Italy

Purpose: To compare the impact of induced astigmatism with four different types of multifocal intraocular lenses (MIOLs). Method: Prospective, comparative, interventional, mono-centered study, including 80 eyes of patients with implantation of four different MIOLs: AcrySof ReSTOR +2.5 D (20 eyes), AcrySof ReSTOR +3.0 D (20 eyes), AcrySof Panoptix (20 eyes) (Alcon Laboratories, Inc., Fort Worth, TX, USA), and Tecnis Symfony ZRX00 (Abbott Medical Optics, Santa Ana, USA) (20 eyes). Patients were followed up for 3 months after surgery. Major parameters were uncorrected (UDVA) and corrected (CDVA) distance visual acuity, subjective refraction and patient satisfaction. Results: Differences between IOLs with regard to the impact of the cylinder sign and axis on visual acuity and patient satisfaction were not significant. With mild added negative cylinder, AcrySof ReSTOR +2.5 D and Tecnis Symfony IOLs maintained the baseline visual acuity, while it was mildly reduced with AcrySof ReSTOR +3.0 D and Panoptix IOLs. With moderate induced cylinder, the Tecnis Symfony IOL maintained good visual acuity and patient associated satisfaction. Panoptix IOL was the IOL most affected by the induced astigmatism with regard to dissatisfaction and visual acuity. The highest tolerance to the astigmatic distortion and blurriness induced with a -1.50 D cylinder was obtained with the Tecnis Symfony IOL. Tecnis Symfony IOL showed less dissatisfaction and less reduction of visual acuity than the other MIOLs. Conclusion: Simulated residual cylinders after the implantation of the Tecnis Symfony IOL up to 1.0 D have a very mild and not clinically relevant impact on visual acuity or patient satisfaction. The ERV IOL showed a better tolerance to unexpected postoperative residual errors than diffractive bifocal and trifocal IOLs.

关键词： Multifocal IOL Astigmatism Tolerance Bifocal Trifocal extended Range of Vision Tecnis Symfony Panoptix AcrySof ReSTOR

Detection of extended Spectrum β-Lactamase Producing Klebsiella pneumoniae and Escherichia coli in Two Hospitals in the Federal Capital Territory, Abuja, Nigeria

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Open Journal of Medical Microbiology 2013年第4期3卷 207-212页

作者： Bolaji Oluwatosin Akanbi Benjamin Destiny Ojonuba Remi Njoku Department of Biological Sciences University of Abuja Nigeria University of Abuja Teaching Hospital Abuja Nigeria

In this study, the prevalence of extended Spectrum Beta-lactamase (ESBL) producing Klebsiella pneumoniae and Escherichia coli isolates from the University of Abuja Teaching Hospital and the National Hospital was determined. A total of two hundred and fifteen (215) clinical isolates were examined, of which 60% were E. coli and 40% K. pneumoniae respectively. The isolates were collected from various samples namely: Stool, Urine, Pus, High Vagina Swab, Sputum and Wound swab. Out of these isolates, 54 of K. pneumoniae were screened to be ESBL negative and 32 as ESBL positive isolates, while 88 and 40 E. coli were also screened as ESBL negative and ESBL positive isolates respectively. These represent 37.9% of all K. pneumoniae isolates and 31.25% of E. coli isolates respectively. The prevalence of ESBL among the species was not however statistically different (p > 0.05). Multiple resistance in these isolates was common and there is the need for routine screening of ESBL in our hospitals to guide rational and effective use of antibiotics.

关键词： extended Spectrum Beta-Lactamase Klebsiella pneumoniae Escherichia coli Nigeria Multidrug Resistance

Intelligent Process Fault Diagnosis for Nonlinear Systems with Uncertain Plant Model via extended State Observer and Soft Computing

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Intelligent Control and Automation 2012年第4期3卷 346-355页

作者： Paul P. Lin Dapeng Ye Zhiqiang Gao Qing Zheng Electrical and Computer Engineering Cleveland State University Cleveland USA Electrical and Computer Engineering Gannon University Erie USA Engineering Dean’s Office Cleveland State University Cleveland USA Mechanical & Electronic Engineering Fujian Agriculture and Forestry University Fuzhou China

There have been many studies on observer-based fault detection and isolation (FDI), such as using unknown input observer and generalized observer. Most of them require a nominal mathematical model of the system. Unlike sensor faults, actuator faults and process faults greatly affect the system dynamics. This paper presents a new process fault diagnosis technique without exact knowledge of the plant model via extended State Observer (ESO) and soft computing. The ESO’s augmented or extended state is used to compute the system dynamics in real time, thereby provides foundation for real-time process fault detection. Based on the input and output data, the ESO identifies the un-modeled or incorrectly modeled dynamics combined with unknown external disturbances in real time and provides vital information for detecting faults with only partial information of the plant, which cannot be easily accomplished with any existing methods. Another advantage of the ESO is its simplicity in tuning only a single parameter. Without the knowledge of the exact plant model, fuzzy inference was developed to isolate faults. A strongly coupled three-tank nonlinear dynamic system was chosen as a case study. In a typical dynamic system, a process fault such as pipe blockage is likely incipient, which requires degree of fault identification at all time. Neural networks were trained to identify faults and also instantly determine degree of fault. The simulation results indicate that the proposed FDI technique effectively detected and isolated faults and also accurately determine the degree of fault. Soft computing (i.e. fuzzy logic and neural networks) makes fault diagnosis intelligent and fast because it provides intuitive logic to the system and real-time input-output mapping.

关键词： Fault Diagnosis extended State Observers Fuzzy Logic Neural Networks

extended Mendelsohn三元系大集的构造

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河北师范大学学报（自然科学版） 2006年第5期30卷 497-499页

作者：王小哲于兰香华北电力大学应用数学系河北保定071000

Mendelsohn三元系大集(LMTS)是一类有向设计的大集,它的存在性问题已完全解决.若在以上的设计中要求有序对(x,x)也出现,则称这样的设计为extended Mendelsohn三元系大集(LEMTS).给出了LEMTS的构造,从而完全解决了LEMTS的存在性问题.

关键词： Mendelsohn三元系大集 extended Mendelsohn三元系大集循环三元组