bluuebunny/crossref_metadata_2025 huggingface dataset:
Pacemaker Placement in Patients with Stroke-Mediated Autonomic Dysregulation
Authors: Alsaad Ali A. , Austin Christopher O. , Robinson Maisha T. , Phillips Michael B.
Published: March 2017

Lateral medullary syndrome (LMS) is an ischemic disease of the medulla oblongata, which involves the territory of the posterior inferior cerebellar artery. Lateral medullary syndrome is often missed as the cause of autonomic dysregulation in patients with recent brain stem stroke. Due to the location of the baroreceptor regulatory center in the lateral medulla oblongata, patients with LMS occasionally have autonomic dysregulation-associated clinical manifestations. We report a case of LMS-associated autonomic dysregulation. The case presented as sinus arrest and syncope, requiring permanent pacemaker placement. A dual-chamber pacemaker was placed, after failure of conservative measures to alleviate the patient’s symptoms. Our case shows the importance of recognizing LMS as a potential cause for life-threatening arrhythmias, heart block, and symptomatic bradycardia. Placement of permanent pacemaker may be necessary in some patients with LMS presenting with syncope, secondary to sinus arrest.
Improving Urban Water Environment in Eastern China by Blending Traditional with Modern Landscape Planning
Authors: Cao Jiajie , Yu Junjun , Tian Yuan , Zhao Cai , Wang Hao
Published: March 2017

As a fundamental part of greenspace, urban water landscape contributes greatly to the ecological system and at the same time supplies a leisure area for residents. The paper did an analysis on the number of aquatic plant communities, the form of water spaces, and water quality condition by investigating 135 quadrats (90 at amphibious boundary and the land, 45 in the water) in 45 transects of 15 urban and suburban parks. We found that water spaces had monotonous forms with low biodiversity and poor water quality. In addition, urban water landscapes hardly provided ecological functions given excessive construction. Accordingly, a proposition to connect tradition with modernism in the improvement and innovation of urban water landscape planning was put forward, and further, the way to achieve it was explored. By taking Qinhu Wetland Park as a case, the principles and specific planning methods on macro- and microperspectives were discussed to guide the development of urban landscape in eastern China.
Dendrobium officinale Kimura et Migo: A Review on Its Ethnopharmacology, Phytochemistry, Pharmacology, and Industrialization
Authors: Tang Hanxiao , Zhao Tianwen , Sheng Yunjie , Zheng Ting , Fu Lingzhu , Zhang Yongsheng
Published: March 2017

Ethnopharmacological Relevance. Dendrobii Officinalis Caulis, the stems of Dendrobium officinale Kimura et Migo, as a tonic herb in Chinese materia medica and health food in folk, has been utilized for the treatment of yin‐deficiency diseases for decades. Methods. Information for analysis of Dendrobium officinale Kimura et Migo was obtained from libraries and Internet scientific databases such as PubMed, Web of Science, Google Scholar, ScienceDirect, Wiley InterScience, Ingenta, Embase, CNKI, and PubChem. Results. Over the past decades, about 190 compounds have been isolated from Dendrobium officinale Kimura et Migo. Its wide modern pharmacological actions in hepatoprotective effect, anticancer effect, hypoglycemic effect, antifatigue effect, gastric ulcer protective effect, and so on were reported. This may mainly attribute to the major and bioactive components: polysaccharides. However, other small molecule components require further study. Conclusions. Due to the lack of systematic data of Dendrobium officinale, it is important to explore its ingredient‐function relationships with modern pharmacology. Recently, studies on the chemical constituents of Dendrobium officinale concentrated in crude polysaccharides and its structure‐activity relationships remain scant. Further research is required to determine the Dendrobium officinale toxicological action and pharmacological mechanisms of other pure ingredients and crude extracts. In addition, investigation is needed for better quality control and novel drug or product development.
A Foreign Body Granuloma of the Buccal Mucosa Induced by Honeybee Sting
Authors: Yamamoto Kazuhiko , Nakayama Yohei , Matsusue Yumiko , Kurihara Miyako , Yagyuu Takahiro , Kirita Tadaaki
Published: March 2017

A foreign body granuloma of the buccal mucosa induced by honeybee sting was reported. The patient was an 82-year-old female who presented with a submucous mass at the right buccal mucosa. The mass was 20 mm in diameter, elastically firm, partly mobile without pain or tenderness, and covered with almost normal mucosa. MR image did not delineate the lesion clearly. Under clinical diagnosis of a benign tumor, the lesion was excised under local anesthesia. The excised lesion was14×11×9 mmin size and solid and yellowish in cut surface. Histologically, the lesion consisted of granulomatous tissue with a few narrow, curved, eosinophilic structures compatible with decomposed fragments of a honeybee sting and was diagnosed as a foreign body granuloma, although the patient did not recall being stung.
Study on Aseismic Characteristics of Tibetan Ancient Timber Structure
Authors: Wang Juan , He Junxiao , Yang Na , Yang Qingshan
Published: March 2017

Tibetan ancient timber structure has great historical, cultural, artistic, and scientific values. The structural configuration of members such as wall, roof, slab, and timber skeleton with semirigid joints is studied in this paper based on field survey results. The aseismic characteristics of Tibetan ancient timber structure have been summarized and introduced. One of the unique features of the Tibetan ancient timber structure is its special beam-column joint which has a semirigid behavior. Numerical simulations of a typical 3-storey structural unit in the Potala Palace are studied. The acceleration responses of the structure under the action of El-Centro seismic waves are studied. Results show that the arrangement of the joints is helpful for seismic resistance of the structure. Most Tibetan ancient timber structures are suffering from different types of damage to certain extent which is vulnerable to seismic actions. Typical damage problems of the structural components are summarized and the main causes of this damage are analyzed. Different rehabilitation methods that can be implemented are discussed, providing references for maintenance of the structures.
Psychological Aspects of Androgen Insensitivity Syndrome: Two Cases Illustrating Therapeutical Challenges
Authors: Pritsini Filippa , Kanakis Georgios A. , Kyrgios Ioannis , Kotanidou Eleni P. , Litou Eleni , Mouzaki Konstantina , Kleisarchaki Aggeliki , Goulis Dimitrios G. , Galli-Tsinopoulou Assimina
Published: March 2017

Androgen Insensitivity Syndrome (AIS) and its heterogeneous phenotypes comprise the pieces of a challenging clinical problem. The lack of standardized guidelines results in controversies regarding the proper diagnostic and therapeutic approach, including the time and type of intervention. Due to its variable phenotype, AIS is not diagnosed at the proper age that would allow optimal psychological and medical support to the patient. Therapeutic approaches are not established, mainly due to the rarity of the disease. In addition, various social and ethical consequences may emerge. The aim of this double case report is to outline the difficulties that may rise during diagnostic, therapeutic, and psychological approach of AIS, especially concerning the handling of the relatives’ reaction.
Gengnianchun, a Traditional Chinese Medicine, Enhances Oxidative Stress Resistance and Lifespan in Caenorhabditis elegans by Modulating daf‐16/FOXO
Authors: Meng Fanhui , Li Jun , Wang Wenjun , Fu Yan
Published: March 2017

Objective. Gengnianchun (GNC), a traditional Chinese medicine (TCM), is primarily used to improve declining functions related to aging. In this study, we investigated its prolongevity and stress resistance properties and explored the associated regulatory mechanism using a Caenorhabditis elegans model. Methods. Wild‐type C. elegans N2 was used for lifespan analysis and oxidative stress resistance assays. Transgenic animals were used to investigate pathways associated with antioxidative stress activity. The effects of GNC on levels of reactive oxygen species (ROS) and expression of specific genes were examined. Results. GNC‐treated wild‐type worms showed an increase in survival time under both normal and oxidative stress conditions. GNC decreased intracellular ROS levels by 67.95%. GNC significantly enhanced the oxidative stress resistance of several mutant strains, suggesting that the protective effect of GNC is independent of the function of these genes. However, the oxidative stress resistance effect of GNC was absent in worms with daf‐16 mutation. We also found upregulation of daf‐16 downstream targets including sod‐3 and mtl‐1. Conclusions. Our findings suggest that GNC extends the lifespan of C. elegans and enhances its resistance to oxidative stress via a daf‐16/FOXO‐dependent pathway. This study also provides a feasible method for screening the biological mechanisms of TCMs.
Enhancing the Cloud Computing Performance by Labeling the Free Node Services as Ready-To-Execute Tasks
Authors: Abujassar Radwan S. , Jazzar Moneef
Published: March 2017

The huge bandwidth and hardware capacity form a high combination together which leads to a vigorous development in the Internet. On the other hand, different problems will come up during the use of the networks such as delay and node tasks load. These problems lead to degrade the network performance and then affect network service for users. In cloud computing, users are looking to be provided with a high level of services from the service provider. In addition, cloud computing service facilitates the execution of complicated tasks that needed high-storage scale for the computation. In this paper, we have implemented a new technique to retain the service and assign tasks to the best and free available node already labeled by the manager node. The Cloud Computing Alarm (CCA) technique is working to provide all information about the services node and which one is ready to receive the task from users. According to the simulation results, the CCA technique is making good enhancements on the QoS which will increase the number of users to use the service. Additionally, the results showed that the CCA technique improved the services without any degrading of network performance by completing each task in less time.
Cytotoxicity and Apoptosis Induction of Ardisia crispa and Its Solvent Partitions against Mus musculus Mammary Carcinoma Cell Line (4T1)
Authors: Nordin Muhammad Luqman , Abdul Kadir Arifah , Zakaria Zainul Amiruddin , Othman Fauziah , Abdullah Rasedee , Abdullah Muhammad Nazrul Hakim
Published: March 2017

This study was conducted to investigate the cytotoxicity and apoptosis effect of A. crispa extract and its solvent partition (ethyl acetate and aqueous extract) against Mus musculus mammary carcinoma cell line (4T1). The normal mouse fibroblast cell line (NIH3T3) was used as comparison for selective cytotoxicity properties. The cytotoxicity evaluation was assessed using MTT assay. AO/PI dual fluorescent staining assay and Annexin V‐FITC were used for apoptosis analysis. Results showed that 80% methanol extract from leaves showed most promising antimammary cancer agent with IC50 value of 42.26 ± 1.82 μg/mL and selective index (SI) value of 10.22. Ethyl acetate was cytotoxic for both cancer and normal cell while aqueous extract exhibited poor cytotoxic effect. 4T1 cells labelled with AO/PI and Annexin V‐FITC and treated with 80% methanol extract demonstrated that the extract induces apoptosis to 4T1 mammary cancer cells. In conclusion, 80% methanol extract of A. crispa was selectively cytotoxic towards 4T1 cells but less cytotoxic towards NIH3T3 cells and induced the cancerous cells into apoptotic stage as early as 6 hours.
Staged Venture Capital Investment considering Unexpected Major Events
Authors: Zhang Yindong , Xiang Kaili , Ding Chuan , Chen Tao
Published: March 2017

This paper presents a dynamic model of capital financing, taking into consideration unexpected major events occurring within continuous time model. We are considering a special jump-diffusion model first described by Samuelson (1973) while using traditional geometric Brownian motion. This paper seeks to accurately show the innovative project valuation when unexpected major events occur and get the analytical results of the project option value. Furthermore, we analyzed the impact of multistaged financing; results indicated that both sources of uncertainty positively impact the project option value; particularly, the option price when considering unexpected major events occurrence is larger than the option price without unexpected major events. Based on a comparative-static analysis, new propositions for optimal amount of investment and optimal level of project are derived from simulations.
64Cu-MM-302 Positron Emission Tomography Quantifies Variability of Enhanced Permeability and Retention of Nanoparticles in Relation to Treatment Response in Patients with Metastatic Breast Cancer
Authors: Lee Helen , Shields Anthony F. , Siegel Barry A. , Miller Kathy D. , Krop Ian , Ma Cynthia X. , LoRusso Patricia M. , Munster Pamela N. , Campbell Karen , Gaddy Daniel F. , Leonard Shannon C. , Geretti Elena , Blocker Stephanie J. , Kirpotin Dmitri B. , Moyo Victor , Wickham Thomas J. , Hendriks Bart S.
Published: March 2017

Purpose: Therapeutic nanoparticles are designed to deliver their drug payloads through enhanced permeability and retention (EPR) in solid tumors. The extent of EPR and its variability in human tumors is highly debated and has been proposed as an explanation for variable responses to therapeutic nanoparticles in clinical studies.

Experimental Design: We assessed the EPR effect in patients using a 64Cu-labeled nanoparticle, 64Cu-MM-302 (64Cu-labeled HER2-targeted PEGylated liposomal doxorubicin), and imaging by PET/CT. Nineteen patients with HER2-positive metastatic breast cancer underwent 2 to 3 PET/CT scans postadministration of 64Cu-MM-302 as part of a clinical trial of MM-302 plus trastuzumab with and without cyclophosphamide (NCT01304797).

Results: Significant background uptake of 64Cu-MM-302 was observed in liver and spleen. Tumor accumulation of 64Cu-MM-302 at 24 to 48 hours varied 35-fold (0.52–18.5 %ID/kg), including deposition in bone and brain lesions, and was independent of systemic plasma exposure. Computational analysis quantified rates of deposition and washout, indicating peak liposome deposition at 24 to 48 hours. Patients were classified on the basis of 64Cu-MM-302 lesion deposition using a cut-off point that is comparable with a response threshold in preclinical studies. In a retrospective exploratory analysis of patient outcomes relating to drug levels in tumor lesions, high 64Cu-MM-302 deposition was associated with more favorable treatment outcomes (HR = 0.42).

Conclusions: These findings provide important evidence and quantification of the EPR effect in human metastatic tumors and support imaging nanoparticle deposition in tumors as a potential means to identify patients well suited for treatment with therapeutic nanoparticles. Clin Cancer Res; 23(15); 4190–202. ©2017 AACR.
Programming of the Hypothalamus-Pituitary-Adrenal Axis by Very Preterm Birth
Authors: Finken Martijn J.J. , van der Voorn Bibian , Hollanders Jonneke J. , Ruys Charlotte A. , de Waard Marita , van Goudoever Johannes B. , Rotteveel Joost
Published: March 2017

Background: Many very preterm (i.e., <32 weeks of gestation) newborns fail to mount an adequate adrenocortical response to stress or illness, termed relative adrenal insufficiency. Conversely, later in life these infants show features of increased glucocorticoid bioactivity, such as abdominal adiposity, insulin resistance, raised blood pressure, shorter stature and internalizing problem behavior. Summary: Studies suggested that very preterm newborns have impairments along multiple levels of the hypothalamus-pituitary-adrenal (HPA) axis. Among the impairment were defects in: (1) the pituitary responsiveness to exogenous corticotropin-releasing hormone, (2) 11β-hydroxylase activity, and (3) the interconversion between cortisol and inert cortisone. There is some evidence suggesting that later in life these infants have an increased basal secretion rate of cortisol and adrenal hyperandrogenism. However, the response to acute (psychosocial) stress was blunted rather than enhanced in them. The mechanisms explaining this switch in HPA axis activity are complex and not yet fully understood. Key Messages: Very preterm newborns have several impairments along the HPA axis that could impede an adequate adrenocortical response to stress or illness. Later in life, these infants are predisposed to increased HPA axis activity, which could partially explain their phenotype.
Predictors of Reversion from Mild Cognitive Impairment to Normal Cognition
Authors: Pandya Seema Y. , Lacritz Laura H. , Weiner Myron F. , Deschner Martin , Woon Fu L.
Published: March 2017

Background/Aims: Few studies have examined predictors of reversion from mild cognitive impairment (MCI) to normal cognition. We sought to identify baseline predictors of reversion, using the National Alzheimer's Coordinating Center Uniform Data Set, by comparing MCI individuals who reverted to normal cognition to those who progressed to dementia. Methods: Participants (n = 1,208) meeting MCI criteria were evaluated at the baseline visit and 3 subsequent annual visits. Clusters of baseline predictors of MCI reversion included demographic/genetic data, global functioning, neuropsychological functioning, medical health/dementia risk score, and neuropsychiatric symptoms. Stepwise logistic regression models identified predictors of MCI reversion per cluster, which were then entered into a final comprehensive model to find overall predictor(s). Results: At 2 years, 175 (14%) reverted to normal cognition, 612 (51%) remained MCI, and 421 (35%) progressed to dementia, with sustained diagnoses at 3 years. Significant variables associated with MCI reversion were younger age, being unmarried, absence of APOE ε4 allele, lower CDR-SOB score, and higher memory/language test scores. Conclusion: A relatively sizable proportion of MCI individuals reverted to normal cognition, which is associated with multiple factors previously noted. Findings may enhance MCI prognostic accuracy and increase precision of early intervention studies of dementia.
Placental Lipid and Fatty Acid Transfer in Maternal Overnutrition
Authors: Lewis Rohan M. , Desoye Gernot
Published: March 2017

Background: The increasing incidence of childhood obesity is a significant public health challenge, the consequences of which extend across the life course. Summary: Diet and exercise are clearly the major contributors to childhood obesity, but the factors predisposing to obesity may become established in the womb. Worryingly maternal overnutrition, in particular when it leads to obesity and diabetes, perpetuate an intergenerational cycle of obesity through its effects on placental function and fetal metabolism. This review will address the ways in which the placental lipid and fatty acid transfer may lay the foundations for obesity in the context of maternal overnutrition. Key Messages: (1) Metabolic changes associated with maternal obesity affect placental nutrient handling. (2) Altered placental nutrient handling may induce pro-adipogenic changes in the fetus, in particular increased fetal insulin. (3) Understanding the effects of maternal obesity on the placenta will aid the development of effective interventions to optimise pregnancy outcomes.
Long-Term Adverse Effects of Early Growth Acceleration or Catch-Up Growth
Authors: Singhal Atul
Published: March 2017

Background: Whilst prevention of growth faltering has both short- and long-term health benefits, whether too fast or accelerated infant growth adversely affects later health outcomes is controversial and a major focus of research. Summary: Many observational studies suggest that rapid weight gain in infancy (upward centile crossing) increases the long-term risk of obesity and non-communicable disease. This association has been seen in infants from low- and high-income countries, in infants born preterm or at term, and those born with normal or low birth weight for gestation. Experimental (randomized) studies in both breast- and formula-fed infants support a causal link between early growth acceleration and infant nutrition and later risk of obesity. These observations suggest that strategies to optimize the pattern of infant growth could make a major contribution to stemming the current global epidemic of non-communicable disease. Key Messages: The optimal pattern of infant weight gain is likely to differ in different populations. The benefits of rapid infant weight gain for later neurodevelopment favors the promotion of rapid growth in infants born preterm. However, growth acceleration in healthy infants born at term (either normal or low birth weight for gestation) is likely to have adverse effects for long-term health.
Adaptive Fuzzy Integral Sliding-Mode Regulator for Induction Motor Using Nonlinear Sliding Surface
Authors: Lu Yong-Kun
Published: March 2017

An adaptive fuzzy integral sliding-mode controller using nonlinear sliding surface is designed for the speed regulator of a field-oriented induction motor drive in this paper. Combining the conventional integral sliding surface with fractional-order integral, a nonlinear sliding surface is proposed for the integral sliding-mode speed control, which can overcome the windup problem and the convergence speed problem. An adaptive fuzzy control term is utilized to approximate the uncertainty. The stability of the controller is analyzed by Lyapunov stability theory. The effectiveness of the proposed speed regulator is demonstrated by the simulation results in comparison with the conventional integral sliding-mode controller based on boundary layer.
Real Coded Genetic Algorithm Based Improvement of Efficiency in Interleaved Boost Converter
Authors: Arundevi M , Valarmathi K , Mahendran R
Published: March 2017

 The reliability, efficiency, and controllability of Photo Voltaic power systems can be increased by embedding the components of a Boost Converter. Currently, the converter technology overcomes the main problems of manufacturing cost, efficiency and mass production. Issue to limit the life span of a Photo Voltaic inverter is the huge electrolytic capacitor across the Direct Current bus for energy decoupling. This paper presents a two-phase interleaved boost converter which ensures 180 angle phase shift between the two interleaved converters. The Proportional Integral controller is used to reshape that the controller attempts to minimize the error by adjusting the control inputs and also real coded genetic algorithm is proposed for tuning of controlling parameters of Proportional Integral controller. The real coded genetic algorithm is applied in the Interleaved Boost Converter with Advanced Pulse Width Modulation Techniques for improving the results of efficiency and reduction of ripple current. Simulation results illustrate the improvement of efficiency and the diminution of ripple current.
A New Control Method for Grid-Connected PV System Based on Quasi-Z-Source Cascaded Multilevel Inverter Using Evolutionary Algorithm
Authors: Mohammadi Hamid Reza , Akhavan Ali
Published: March 2017

In this paper, a new control method for quasi-Z-source cascaded multilevel inverter based grid-connected photovoltaic (PV) system is proposed. The proposed method is capable of boosting the PV array voltage to a higher level and solves the imbalance problem of DC-link voltage in traditional cascaded H-bridge inverters. The proposed control system adjusts the grid injected current in phase with the grid voltage and achieves independent maximum power point tracking (MPPT) for the separate PV arrays. To achieve these goals, the proportional-integral (PI) controllers are employed for each module. For achieving the best performance, this paper presents an optimum approach to design the controller parameters using particle swarm optimization (PSO). The primary design goal is to obtain good response by minimizing the integral absolute error. Also, the transient response is guaranteed by minimizing the overshoot, settling time and rise time of the system response. The effectiveness of the new proposed control method has been verified through simulation studies based on a seven level quasi-Z-Source cascaded multilevel inverter.
A Simple Strategy of Controlling a Balanced Voltage Capacitor in Single Phase Five-Level Inverter
Authors: Pratomo Leonardus Heru , Wijaya F. Danang , Firmansyah Eka
Published: March 2017

The five-level inverter has been used for many applications in renewable energy systems. Even though its harmonic distortion was lower than the conventional two-level inverter. The five-level converter has some disadvantages such as increasing power semiconductor, complex pulse width modulation control methods, and problem with the voltage balancing of the capacitor. This paper aims to propose a modified five-level inverter based on sinusoidal pulse width modulation using phase shifted carrier to enhancing the capacitor voltage balancing. This modified five-level inverter reduces the overall cost and the complexity of the pulse width modulator. Thus making the proposed control system highly simple. The performance and its controller were validated by means of standard laboratory equipments. The analysis, simulation and implementation result showed better performance of five-level inverter.
A New Multilevel Active Power Filter Using Switches Meticulously Controlled
Authors: Zahzouh Zoubir , Khochmane Lakhdar , Haddouche Ali
Published: March 2017

Shunt active power filter based on multilevel inverter is used to compensate the power factor and to delete the harmonics. This one permits to reduce the inverse voltages applied to the filter switches and their switching frequencies. Nevertheless, the high number of used switches requires a complicated controller and increases the switching losses; where the necessity of finding another resolution system. In this work a new topology of multilevel inverter is proposed as a shunt active power filter using two IGBT transistors in series of opposite sense meticulously controlled by a parallel control algorithm, with the concept of reduced number of six switches which are able to create five levels of the output voltage. This system substute the classical system of eight switches. The harmonic currents identification is carried out using the instantaneous active and reactive power method. The simulation is performed using Matlab/Simulink. The obtained results show that the filtering performances are well enhanced.
Experimental Study Of SBPWM For Z-Source Inverter Five Phase
Authors: Bakar Mohd Shafie , Abd. Rahim Nasrudin , Daniyal Hamdan , Ghazali Kamarul Hawari
Published: March 2017

On the basis of a conventional Z-source inverter, this paper presents an extension of the existing study about a driving scheme implementation of a simple boost pulse width modulation under open loop system for five phase two level system. The impact of design parameter (fixed modulation index and switching frequency) versus performance parameter (capacitor voltage, inductor current, total harmonic distortion and DC link voltage) are studied and analysed. To validate the advantages of Z-source five-phase inverter, the driving scheme are simulated using Matlab/Simulink and verified with real-time target board eZdspTM TMS320F28335. From the study, it was found that under specified modulation index and switching frequency, the THD of an output current fulfilled the EN61000-3-2 standard.
Bearingless Permanent Magnet Synchronous Motor using Independent Control
Authors: Mamat Normaisharah , Abdul Karim Kasrul , Ibrahim Zulkiflie , Sutikno Tole , Ahmad Tarusan Siti Azura , Jidin Auzani
Published: March 2017

Bearingless permanent magnet synchronous motor (BPMSM) combines the characteristic of the conventional permanent magent synchronous motor and magnetic bearing in one electric motor. BPMSM is a kind of high performance motor due to having both advantages of PMSM and magnetic bearing with simple structure, high efficiency, and reasonable cost. The research on BPMSM is to design and analyse BPMSM by using Maxwell 2-Dimensional of ANSYS Finite Element Method (FEM). Independent suspension force model and bearingless PMSM model are developed by using the method of suspension force. Then, the mathematical model of electromagnetic torque and radial suspension force has been developed by using Matlab/Simulink. The relation between force, current, distance and other parameter are determined. This research covered the principle of suspension force, the mathematical model, FEM analysis and digital control system of bearingless PMSM. This kind of motor is widely used in high speed application such as compressors, pumps and turbines.
Closed Loop Analysis of Bridgeless SEPIC Converter for Drive Application
Authors: Mani Gopinath , Gopu G.
Published: March 2017

In this paper closed loop analysis of Single phase AC-DC Bridgeless Single Ended Primary Inductance Converter (SEPIC) for Power Factor Correction (PFC) rectifier is analyzed. In this topology the absence of an input diode bridge and the due to presence of two semiconductor switches in the current flowing path during each switching cycle which will results in lesser conduction losses and improved thermal management compared to the conventional converters. In this paper the operational principles, Frequency analysis, and design equations of the proposed converter are described in detail. Performance of the proposed SEPIC PFC rectifier are carried out using Matlab Simulink software and results are presented.
Push-Pull Converter Fed Three-Phase Inverter for Residential and Motor Load
Authors: Babu Samuel Rajesh
Published: March 2017

The proposed paper is an new approach for power conditioning of a PV (photo-voltaic) cell array. The main objective is to investigate an approach to provide and improve the delivered electric energy by means of power conditioning structures with the use of alternative renewable resources (ARRs) for remote rural residential or industrial non-linear loads. This approach employs a series-combined connected boost and buck boost DC-DC converter for power conditioning of the dc voltage provided by a photo-voltaic array. The input voltage to the combined converters is 100 V provided from two series connected PV cells, which is converted and increased to 200 V at the dc output voltage. Series-combined connected boost and buck-boost DC-DC converters operate  alternatively. This helps to reduce the input ripple current and provide the required 400 Vdc on a sinusoidal PWM three-phase inverter. Analysis of the two series-combined DC-DC converters is presented along with simulation results. Simulations of the series-combined DC-DC converters are presented with an output DC voltage of 200 V and a maximum output load of Po = 600 W.
Design and Control for the Buck-Boost Converter Combining 1-Plus-D Converter and Synchronous Rectified Buck Converters
Authors: Naik Jeevan
Published: March 2017

In this paper, a design and control for the buck-boost converter, i.e., 1-plus-D converter with a positive output voltage, is presented, which combines the 1-plus-D converter and the synchronous rectified (SR) buck converter. By doing so, the problem in voltage bucking of the 1-plus-D converter can be solved, thereby increasing the application capability of the 1-plus-D converter. Since such a converter operates in continuous conduction mode inherently, it possesses the nonpulsating output current, thereby not only decreasing the current stress on the output capacitor but also reducing the output voltage ripple. Above all, both the 1-plus-D converter and the SR buck converter, combined into a buck–boost converter with no right-half plane zero, use the same power switches, thereby causing the required circuit to be compact and the corresponding cost to be down. Furthermore, during the magnetization period, the input voltage of the 1-plus-D converter comes from the input voltage source, whereas during the demagnetization period, the input voltage of the 1-plus-D converter comes from the output voltage of the SR buck converter.
A New Multilevel Inverter Structure For High-Power Applications using Multi-carrier PWM Switching Strategy
Authors: Alishah Rasoul Shalchi , Hosseini Seyyed Hossein
Published: March 2017

In recent, several numbers of multilevel inverter structures have been introduced that the numbers of circuit devices have been reduced.  This paper introduces a new structure for multilevel inverter which can be used in high-power applications. The proposed topology is based on cascaded connection of basic units. This topology consists of minimum number of circuit components such as IGBT, gate driver circuit and antiparallel diode. For proposed topology, two methods are presented for determination of dc voltage sources values. Multi-carrier PWM method for 25-level proposed topology is used. Verification of the analytical results is done using MATLAB simulation.
Supply Power Factor Improvement in Ozone Generator System Using Active Power Factor Correction Converter
Authors: Udhayakumar G. , M R Rashmi , Patel K. , Ramesh G.P. , A Suresh
Published: March 2017

Artificial Ozone Generating system needs High Voltage, High Frequency supply. The Ozonator distorts the supply currents and henceforth affect the supply power factor. This paper presents the performance comparison of PWM inverter to Power Factor Corrected (PFC) converter with PWM inverter based High-voltage High-frequency power supply for ozone generator system. The conventional inverter has front end bridge rectifier with smoothing capacitor. It draws non-sinusoidal current from ac mains; as a result input supply has more harmonics and poor power factor. Hence, there is a continuous need for power factor improvement and reduction of line current harmonics.  The proposed system has active power factor correction converter which is used to achieve sinusoidal current and improve the supply power factor. The active PFC converter with PWM inverter fed ozone generator generates more ozone output compared to the conventional inverter. Thus the proposed system has less current harmonics and better input power factor compared to the conventional system.  The performance of the both inverters are compared and analyzed with the help of simulation results presented in this paper.
Fault Ride-Through Capability of DSTATCOM for Distributed Wind Generation System
Authors: Aggarwal Manju , Singh Madhusudan , Gupta S. K.
Published: March 2017

In this paper, fault ride through analysis of a low voltage distribution system augmented with distributed wind generation using squirrel cage induction generator and distribution static compensator (DSTATCOM) is carried out through modeling and simulation study in MATLAB. The impact of different types of unbalanced (single line to ground) fault in a low voltage distribution system in normal and severe conditions are studied and analysed in details. Analysis on system instability is also shown in case of sever fault condition. A distribution Static Compensator (DSTATCOM) is used to improve fault ride through (FRT) capability of wind generation system by compensating positive sequence voltage. A comparison of dynamic response of the system with and without DSTATCOM and effects of DSTATCOM on voltage and generator speed are presented. The simulation results shows that DSTATCOM is capable of reducing the voltage dips and improving the voltage profiles by providing reactive power support to distributed wind generation system under balanced as well as unbalanced faults condition and enhances the fault ride through capability of the wind generator
A Modified Bridgeless Converter for SRM Drive with Reduced Ripple Current
Authors: Krishnakumar Maheswari C , Thottungal Rani , A.C Divya
Published: March 2017

Single Phase Switched Reluctance Motor is more popular in many industrial purposes for high speed applications because of its robust and rugged construction. For low cost and variable speed drive applications SRM are widely used.Due to doubly salient structure of motor, the torque pulsations are high when compared to other sinusoidal machines. The major drawback in using SRM drive is torque pulsations and increased number of switching components. In order to overcome these drawbacks, a bridgeless Single Ended Primary Inductor Converter (SEPIC) is proposed. The major advantages of this converter are continuous output current,smaller voltage ripple and reduced semiconductor current stress when compared to the conventional SEPIC converter. The ripple free input current is obtained by using additional winding of input inductor and auxiliary capacitors. To achieve high efficiency, active power factor correction circuits (PFC) are employed to precise the power factor. Further, the unity power factor can be obtained by making the input current during switching period proportional to the input voltage is proposed. The proposed system consists of reduced components and it is also capable of reducing the conduction losses. The working principles and the waveforms of proposed converter are analyzed. To analyze the circuit operation, theoretical analysis and simulation results are provided. Finally, the  comparison between the waveforms of conventional SEPIC and proposed system is presented by using MATLAB/Simulink tools.
A Single-Phase Dual-Stage PV-Grid System with Active Filtering
Authors: Riyadi Slamet , Haroen Yanuarsyah
Published: March 2017

Integrating photovoltaic based electricity into the grid and power quality improvement have become two major issues in electrical system. Formerly, these can be solved by using two converter systems separately, a PV-Grid System and an active power filter. But recent technology uses only a converter system to do both function. An existed shunt active power filter (SAPF) can be modified to form a dual-stage PV-Grid with active filtering capability. In this paper, a PV-Grid System that is capable to transfer all power generated by PV modules and reduce harmonic contents is proposed. The system was formed by connecting a boost chopper as a Maximum Power Point Tracker and PV modules to the DC-link capacitor of a single-phase SAPF. It just needed a current transducer and also required simpler control circuits. A voltage controller was needed to achieve power equilibrium while a current controller was needed to make the grid current sinusoidal with unity power factor. To verify the analysis, simulations and experiments were done.
On the Performances Investigation of Different Surface Mounted Permanent Magnet Machines
Authors: Ali Mansouri , Hejra Msaddek , Hafedh Trabelsi
Published: March 2017

In recent years, permanent magnet machines have become a common choice in many industrial applications. Therefore, several structures have been developed, and the choice of a topology designed for a specified application requires the knowledge of the advantages and disadvantages of different topologies. The present work deals with the evaluation of the performances of different radial flux surface-mounted permanent magnet motors designed for an electric vehicle motor application. The objective of this survey is to show the effect of the rotor position (inner or outer) and the magnets segmentation on the machine output torque and iron losses. In this context, four machines with: (i) inner rotor, (ii) inner rotor segmented magnets, (iii) outer rotor and (iv) outer rotor segmented magnets have been designed and studied. All these machines have the same geometrical dimensions and current loading. The main idea is to develop a machine with smoothness torque, lower torque ondulation, lower iron losses, and which is mechanically robust. Firstly, the output torque of the different structure is computed. Secondly, by means of an improved analytical model coupled with 2 dimensional transient finite element analysis (FEA), the machines iron losses are predicted.
A Novel Rotor Resistance Estimation Technique for Vector Controlled Induction Motor Drive Using TS Fuzzy
Authors: Chacko Saji , N.Bhende Chandrashekhar , Jain Shailendra , Nema R.K.
Published: March 2017

Induction motor with indirect field oriented control is well suited for high performance applications due to its excellent dynamic behavior. But, the indirect field oriented controller is sensitive to variations in rotor time constant, especially variation in rotor resistance. In this study a scheme based on the Rotor flux Model Reference Adaptive Controller is used for on line identification of the rotor resistance and thus improving the steady state performance of the drive.  The overriding feature of this estimation technique is the accurate identification of rotor resistance especially during transient and steady state conditions when the drive is operating at full load and at zero motor speed condition. Moroever, the effectiveness of the TS fuzzy controller utilizing rotor flux for online estimation of rotor resistance for four quadrant operation of motor drive is investigated and compared with the conventional PI and Mamdani fuzzy controller Simulation results in MATLAB/Simulink environment.have been presented  to confirm the effectiviness of the technique.
Simulation and dSPACE Based Implementation of Various PWM Strategies for A New H-Type FCMLI Topology
Authors: Balamurugan Chinnapettai Ramalingam , Natarajan S.P. , Anandhi T.S. , Shanthi B.
Published: March 2017

Depending on the number of levels in output voltage, inverters can be divided into two categories: two level inverter and Multi Level Inverters (MLIs). An inverter topology for high voltage and high power applications that seems to be gaining interest is the MLI. In high power and high voltage applications, the two level inverters have some limitations in operating at high frequency mainly due to switching losses and constraints of device rating.In this paper, a three phase H + type FCMLI (Flying Capacitor MLI) using sinusoidal reference, third harmonic injection reference, 60 degree reference and stepped wave reference are initially developed using SIMULINK and then implemented in real time environment using dSPACE. In H-type FCMLI with R-load it is inferred that bipolar COPWM-C provides output with relatively low distortion for 60 degree reference and bipolar COPWM-C strategy is found to perform better since it provides relatively higher fundamental RMS output voltage for THI reference. The five level output voltages of the chosen MLIs obtained using the MATLAB and dSPACE based PWM (Pulse Width Modulation) strategies and the corresponding %THD (Total Harmonic Distortion), VRMS (fundamental), CF (Crest Factor) and FF (Form Factor) are presented and analyzed.
Investigation on Chassis Dynamometer with Capability to Test Regenerative Braking Function
Authors: Othman Nurul Azwa , Daniyal Hamdan
Published: March 2017

An investigation-based approach to a bidirectional power flow method for testing regenerative braking function on a chassis dynamometer is presented. The requirements and specifications for capability to test regenerative braking function of Electric Vehicle (EV) emulated by using a bidirectional chassis dynamometer are discussed. The dynamometer emulates road load conditions during testing, and regenerative braking is able to test their function while the vehicle is in deceleration condition. Performances of power requirement are illustrated and translated into sequence diagram. It is shown that the proposed topology is particularly advantageous in generating and regenerating power for energy consumption. The overview of conventional chassis dynamometer and the proposed chassis dynamometer is compared to investigate the parameter in the development of regenerative braking test.
Development and Simulation of Stand Alone Photovoltaic Model Using Matlab/Simulink
Authors: Sharma Himanshu , Pal Nitai , Singh Yaduvir , Sadhu Pradip Kumar
Published: March 2017

This paper presents the implementation of a generalized photovoltaic model using Matlab/Simulink software package, which can be representative of PV cell, module for easy use on simulation platform. The proposed model is designed with a user-friendly icon and a dialog box like Simulink block libraries which makes the generalized PV model easily simulated and analyzed in conjunction with power electronics. Taking the effect of sunlight irradiance and cell temperature into consideration, the output current and power characteristics of PV model are simulated and optimized using the proposed model. The proposed model enables the dynamics of PV power system to be easily simulated, analyzed and optimized.
Voltage and Frequency Control of Variable Speed Induction Generator using One Cycle Control Technique
Authors: Elango T. , Kumar A.Senthil
Published: March 2017

Induction generators are widely used to extract the energy from renewable sources, particularly as a wind power generator either grid connected or isolated operation. The problem associated with stand-alone mode operation is voltage and frequency control. An electronic load controller is used for frequency / voltage control. It uses PI controller to generate the gating signal for the DC chopper. This method has the fault of bad dynamic response and thedistortion of output voltage at zero-crossing. To overcome the defect of PI controller when steady state error is equal to zero, a one cycle control technique suggested and implemented. Simulation of wind driven self-excited induction generator (SEIG) performance is studied and results are discussed.
WAMS-Based SSR Damping Controller Design for FACTS Devices and Investigating Effects of Communication Delays
Authors: Farsadi Mortaza , Ghasemi Arash
Published: March 2017

Recent technological progresses in the wide-area measurement systems (WAMS) are realizing the centralized controls as a breakthrough for improving the power systems stability. The most challenging deficiency against WAMS technology is related to communication delays. If this latency is neglected, it can deteriorate the damping performance of closed loop control or even degrade the system stability. This paper investigates a conventional Wide Area Damping Controller (WADC) for a static synchronous series compensator (SSSC) to damp out the Sub-Synchronous Resonance (SSR) and also investigation of the destructive effect of time delay in remote feedback signal. A new optimization algorithm called teaching-learning-based- optimization (TLBO) algorithm has been implemented to normalize and optimize the parameters of the global SSR damping controller. The IEEE Second Benchmark Model is considered as the system under study and all simulations are carried out in MATLAB/SIMULINK environment.
The Camparison of Harmonic Distortion Self-Excited Induction Generator with Isolated Synchronous Generator under Non-linear Loads
Authors: Nazir Refdinal , Krismadinata Krismadinata , Amalia Rizka
Published: March 2017

In this paper, the harmonic distortion for Self-Excited Induction Generator (SEIG) and an isolated synchronous generator (ISG) under non-linear load during steady state conditions are analyzed. The voltage and current harmonics distortion for both generators are calculated using the transfer function method in frequency domain for SEIG and phasor diagram method for ISG. This analysis is done independently one by one component for all harmonic components appear. The analysis results for both generators are verified to the laboratory test results. For loading with the same non-linear load to both generators, the harmonics distortion on the stator windings of SEIG was smaller than compare ISG. In addition, the harmonic distortion effects on other loads connected to PCC point of SEIG was lower than the other loads connected to ISG.