bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability, rheological property and oil-displacement mechanism of a dispersed low-elastic microsphere system for enhanced oil recovery
Authors: Yang Hongbin , Kang Wanli , Wu Hairong , Yu Yang , Zhu Zhou , Wang Pengxiang , Zhang Xiangfeng , Sarsenbekuly Bauyrzhan
Published: January 2017

The dispersed low-elastic microsphere system shows shear-thickening behavior because of the microstructure change and the interaction of internal forces.
Tribological characteristic and mechanism analysis of borate ester as a lubricant additive in different base oils
Authors: Yang Guangbin , Zhao Junhua , Cui Lu , Song Shiyong , Zhang Shengmao , Yu Laigui , Zhang Pingyu
Published: January 2017

A kind of N-containing borate ester (DEBE) with a double five-member-ring structure as a lubricant additive was synthesized by using boric acid, diethanolamine and alkylphenol polyoxyethylene ether as the starting materials.
Six new coordination compounds based on rigid 5-(3-carboxy-phenyl)-pyridine-2-carboxylic acid: synthesis, structural variations and properties
Authors: Song Jiang-Feng , Jia Ying-Ying , Zhou Rui-Sha , Li Si-Zhe , Qiu Xiao-Min , Liu Jie
Published: January 2017

Compounds 1–6 have rich structural chemistry ranging from mononuclear (1 and 2), one-dimensional (3 and 4), two-dimensional (5) to three-dimensional (6) structures.
Effects of Mn-doped ceria oxygen-storage material on oxidation activity of diesel soot
Authors: Huang He , Liu Junheng , Sun Ping , Ye Song , Liu Bingxia
Published: January 2017

TG and DTG curves of diesel particle shift to the low temperature region with the increase of Mn doping into CeO2system, which indicates that the particle ignition combustion temperature decreases.
Role of Tf2N− anions in the ionic liquid–water distribution of europium(iii) chelates
Authors: Okamura Hiroyuki , Aoyagi Noboru , Shimojo Kojiro , Naganawa Hirochika , Imura Hisanori
Published: January 2017

The replacement of water molecules of [Eu(tta)3(H2O)3] with Tf2N− was evidenced in water-saturated [Cnmim][Tf2N] by time-resolved laser-induced fluorescence spectroscopy.
Centrosymmetric to noncentrosymmetric structural transformation of new quaternary selenides induced by isolated dimeric [Sn2Se4] units: from Ba8Ga2Sn7Se18to Ba10Ga2Sn9Se22
Authors: Li Yan-Yan , Wang Jin-Qiu , Liu Peng-Fei , Lin Hua , Chen Ling , Wu Li-Ming
Published: January 2017

An interesting centrosymmetric to noncentrosymmetric structure transformation from Ba8Ga2Sn7Se18to Ba10Ga2Sn9Se22induced by isolated dimeric [Sn2Se4] units was reported.
Nanoparticle functionalized laser patterned substrate: an innovative route towards low cost biomimetic platforms
Authors: Bagga K. , McCann R. , O'Sullivan F. , Ghosh P. , Krishnamurthy S. , Stalcup A. , Vázquez M. , Brabazon D.
Published: January 2017

Integration of nanotechnology and advanced manufacturing processes presents an attractive route to produce devices for adaptive biomedical device technologies.
High performance asymmetric supercapacitors with ultrahigh energy density based on hierarchical carbon nanotubes@NiO core–shell nanosheets and defect-introduced graphene sheets with hole structure
Authors: Qiu Zenghui , He Dawei , Wang Yongsheng , Zhao Xuan , Zhao Wen , Wu Honglu
Published: January 2017

In this work, we report a fast and cost-effective cobalt catalyzed gasification strategy to obtain defect-introduced graphene sheets (DGNs) with hole structure.
Modification of thermal conductivity and thermal boundary resistance of amorphous Si thin films by Al doping
Authors: Zhan Tianzhuo , Goto Masahiro , Xu Yibin , Kinoshita Yohei , Ishikiriyama Mamoru , Nishimura Chikashi
Published: January 2017

We investigate the effects of Al doping on the thermal conductivity and thermal boundary resistance of a-Si thin films.
Graphene/polyaniline@carbon cloth composite as a high-performance flexible supercapacitor electrode prepared by a one-step electrochemical co-deposition method
Authors: Wen Lele , Li Ke , Liu Jingjing , Huang Yanshan , Bu Fanxing , Zhao Bin , Xu Yuxi
Published: January 2017

A one-step electrochemical co-deposition method was used to prepare a graphene/polyaniline composite on carbon cloth for high-performance flexible supercapacitors.
Mesoporous cerium–zirconium oxides modified with gold and copper – synthesis, characterization and performance in selective oxidation of glycerol
Authors: Kaminski Piotr , Ziolek Maria , van Bokhoven Jeroen A.
Published: January 2017

Au–Cu interaction on Ce–Zr oxides leads to the increase of activity in glycerol oxidation and selectivity to glyceric acid.
Highly efficient triazine/carbazole-based host material for green phosphorescent organic light-emitting diodes with low efficiency roll-off
Authors: Hu Mingming , Liu Yang , Chen Yi , Song Wenxuan , Gao Lei , Mu Haichuan , Huang Jinhai , Su Jianhua
Published: January 2017

Two novel triazin/carbazole-based host materials were designed and synthesized, which demonstrated outstanding EL performance with maximum CE, PE and EQE of 69.3 cd A−1, 54.2 lm W−1 and 21.9%, respectively.
Preparation of a polyvinylidene fluoride tree-like nanofiber mat loaded with manganese dioxide for highly efficient lead adsorption
Authors: Li Zongjie , Kang Weimin , Wei Na , Qiu Jiuan , Sun Cheng , Cheng Bowen
Published: January 2017

A novel polyvinylidene fluoride tree-like structure nanofiber mat loaded with manganese dioxide as a highly efficient lead adsorbent was fabricated.
Design of boron vacancy enhanced spin filtering graphene/BN zigzag nanoribbon heterojunctions
Authors: Jiang Xiaohui , Zou Dongqing , Cui Bin , Fang Changfeng , Liu Wen , Kong Xiangmu , Liu Desheng
Published: January 2017

The spin-polarized electronic transport properties of zigzag graphene nanoribbons (ZGNRs) and boron nitride nanoribbons (ZBNNRs) heterojunctions with a boron vacancy are investigated under an external electric field.
Fourier transform ion mobility spectrometry with multinozzle emitter array electrospray ionization
Authors: Shen Hongling , Jia Xu , Meng Qingyan , Liu Wenjie , Hill Herbert H.
Published: January 2017

Fourier transform ion mobility spectrometry (FT-IMS) is a useful multiplexing method for improving the duty cycle (DC) of IMS from 1 to 25% when using an entrance and exit ion gate to modulate the ion current with a synchronized square wave chirp.
Effective removal of chemical warfare agent simulants using water stable metal–organic frameworks: mechanistic study and structure–property correlation
Authors: Asha P. , Sinha Mekhola , Mandal Sukhendu
Published: January 2017

Water stable zirconium based MOFs are used for the efficient adsorptive removal of chemical warfare agent simulants from aqueous medium.
Valleytronics of III–V solid solutions for thermoelectric application
Authors: Norouzzadeh Payam , Shakouri Ali , Vashaee Daryoosh
Published: January 2017

It is shown that the degeneracy of the bandstructure has different impacts on thermoelectric properties of III–V materials.
Novel Bi2O2CO3/polypyrrole/g-C3N4nanocomposites with efficient photocatalytic and nonlinear optical properties
Authors: Zhao Wei , Wang Yun , Wang Aijian , Qian Jun , Zhu Weihua , Dou Shengping , Wang Qian , Zhong Qin , Chen Aihua
Published: January 2017

A series of novel Bi2O2CO3/polypyrrole/g-C3N4nanocomposites loaded with different contents of g-C3N4was demonstrated for recyclable photocatalysis and nonlinear optical applications.
Study on the stabilization mechanism of crude oil emulsion with an amphiphilic polymer using the β-cyclodextrin inclusion method
Authors: Lu Yao , Kang Wanli , Jiang Jiatong , Chen Jun , Xu Derong , Zhang Pengyi , Zhang Liming , Feng Haishun , Wu Hairong
Published: January 2017

The β-cyclodextrin inclusion method to investigate crude oil emulsions stabilized by amphiphilic polymers is proposed.
Rhodium(i)-catalyzed stereoselective [4+2] cycloaddition of oxetanols with alkynes through C(sp3)–C(sp3) bond cleavage
Authors: Guo Rui , Zheng Xinxin , Zhang Dayong , Zhang Guozhu
Published: January 2017

An efficient and convenient synthesis of highly functionalized dihydropyrans has been achieved through rhodium(i)-catalysed tandem C(sp3)–C(sp3) bond cleavage and annulation of oxetanols with alkynes.
Dimensional heterostructures of 1D CdS/2D ZnIn2S4 composited with 2D graphene: designed synthesis and superior photocatalytic performance
Authors: Tian Qingyong , Wu Wei , Liu Jun , Wu Zhaohui , Yao Weijing , Ding Jin , Jiang Changzhong
Published: January 2017

Multidimensional heterostructure of 1D/2D CdS/ZnIn2S4 with 2D RGO are successfully synthesized, which exhibit superior photoactivity and good stability for the degradation of organic dyes.
Preparation and photoluminescence properties of yellow-emitting CuInS2/ZnS quantum dots embedded in TMAS-derived silica
Authors: Wada Chikako , Iso Yoshiki , Isobe Tetsuhiko , Sasaki Hirokazu
Published: January 2017

Photostable silica composites containing CuInS2/ZnS/ZnS quantum dots were fabricated using a sol–gel method. Their photoluminescence quantum yields were 43–47%.
Exploring the Relevance of Items in the Communicative Participation Item Bank (CPIB) for Individuals With Hearing Loss
Authors: Miller Christi W. , Baylor Carolyn R. , Birch Kristen , Yorkston Kathryn M.
Published: January 2017

Purpose

The Communicative Participation Item Bank (CPIB) was developed to evaluate participation restrictions in communication situations for individuals with speech and language disorders. This study evaluated the potential relevance of CPIB items for individuals with hearing loss.

Method

Cognitive interviews were conducted with 17 adults with a range of treated and untreated hearing loss, who responded to 46 items. Interviews were continued until saturation was reached and prevalent trends emerged. A focus group was also conducted with 3 experienced audiologists to seek their views on the CPIB. Analysis of data included qualitative and quantitative approaches.

Results

The majority of the items were applicable to individuals with hearing loss; however, 12 items were identified as potentially not relevant. This was largely attributed to the items' focus on speech production rather than hearing. The results from the focus group were in agreement for a majority of items.

Conclusions

The next step in validating the CPIB for individuals with hearing loss is a psychometric analysis on a large sample. Possible outcomes could be that the CPIB is considered valid in its entirety or the creation of a new questionnaire or a hearing loss–specific short form with a subset of items is necessary.
Assessment With Children Who Need Augmentative and Alternative Communication (AAC): Clinical Decisions of AAC Specialists
Authors: Lund Shelley K. , Quach Wendy , Weissling Kristy , McKelvey Miechelle , Dietz Aimee
Published: January 2017

Purpose

The purpose of this study was to explore how speech-language pathologists (SLPs) who are augmentative and alternative communication (AAC) specialists approach the assessment process for 2 case studies, 1 child with cerebral palsy and 1 with autism spectrum disorder. The aim of the study was to answer the following questions: (a) How do clinicians with expertise approach the AAC assessment process for children with developmental disabilities? (b) Can any initial hypothesis be drawn about how SLPs approach the assessment of children with motor versus social interactive deficits?

Method

This study used a phenomenological qualitative design. The researchers conducted 2 in-depth, semistructured interviews with 8 SLPs who specialized in AAC and self-identified as primarily working with children.

Results

Four major themes emerged from the data: area of assessment, method of assessment, evaluation preparation, and parent education. Each major theme contained multiple subthemes and categories within those subthemes.

Conclusions

Participants discussed similar areas of assessment for both cases, indicating that some aspects of AAC assessment are universal. However, the specific aspects of what they were assessing and how they went about assessing them differed between the 2 cases. The results of the current study provide an outline of an assessment protocol for children with complex communication needs.
Design of metallic parabolic anechoic chamber for compact range measurement
Authors: Farahbakhsh A. , Zarifi D.
Published: January 2017

Anechoic chambers are used for indoor antenna measurements. The common method for anechoic chamber construction is to cover all inside walls by the EM absorbers. A fully metallic parabolic chamber is presented in which the propagation of the EM waves inside the chamber is controlled and they are guided to an absorber. In the proposed method, an appropriate quiet zone with plane wave illumination is obtained, and unlike ordinary anechoic chambers the absorber usage is decreased greatly. The performance of the chamber is evaluated by simulation and the results showed that the proposed method could provide a useful technique for the compact range antenna measurements.
Design of novel tanh/linear dual profiled smooth horn with low sidelobes
Authors: Wang Junbo , Yao Yuan , Yu Junsheng , Chen Xiaodong
Published: January 2017

A novel smooth horn with tanh/linear dual profile is proposed and the low sidelobe level is achieved. Measured results demonstrate that sidelobes <−37 dB can be achieved on the principal cuts of designed radiation pattern at 92–97 GHz. Also, the measurements are in accordance with the simulated results. It is shown that low sidelobe level can be obtained by the proposed horn geometry without tremendous amounts of time and money designing and manufacturing.
Performance analysis of the 2DoF direct drive induction motor applying composite multilayer method
Authors: Si Jikai , Xie Lujia , Cao Wenping , Hu Yihua , Feng Haichao
Published: January 2017

This study presents a composite multilayer method (CMM) to evaluate the performance of a two‐degree‐of‐freedom (2DoF) direct drive induction motor (2DoFDDIM) whose solid rotor is coated with a copper layer. It includes a rotary part and a linear part. Based on the traditional multilayer theory, a complete 2DoFDDIM CMM computer program importing propagation constants is built. Due to the complex magnetic field in a 2DoFDDIM, this study mainly analyses it from the perspective of a single DOF motor. An equivalent circuit for the rotary part of the 2DoFDDIM is then derived applying CMM and the 2D magnetic field distribution is obtained by solving Maxwell's equations in motor layers. The developed torques, power factors and stator currents of the rotary part with different slips and the latter two of the linear part at zero speed are calculated by CMM, which are then compared with results from the finite element method (FEM) and experimental results. The computation time of the CMM is far less than that of the FEM. The acceptable accuracy confirms the effectiveness of the CMM for analysis and performance calculations of the 2DoFDDIM.
No‐load losses based method to detect demagnetisation fault in permanent magnet synchronous motors with parallel branches
Authors: Hou Zhaowen , Huang Jin , Liu He , Liu Zijian , Ye Ming , Yang Jiaqiang
Published: January 2017

For permanent magnet synchronous motors with parallel branches, circulating currents are induced by a partial demagnetisation fault. The induced currents increase the losses of the motor. Therefore, detecting such a fault becomes possible by analysing the motor losses. This study analyses the effects of the partial demagnetisation fault and defines an index, which is the ratio of increased losses and total losses when the motor is under no‐load conditions, to monitor the condition of the rotor magnets. The method is easily implemented and sensitive to the fault. The experimental results validate the effectiveness of the proposed method.
Decentralised power sharing control strategy in LV microgrids under unbalanced load conditions
Authors: Alizadeh Ebrahim , Birjandi Aliakbar Motie , Hamzeh Mohsen
Published: January 2017

In this paper, a decentralized control strategy for inverter‐based distributed generation (DG) is proposed to enhance the accuracy of power sharing under unbalanced load conditions in low‐voltage microgrids. The proposed method includes two important saliences: (1) accurate unbalanced current injection from DGs, and (2) reduction of circulating real and reactive powers in an islanded microgrid. The features are complied with the proposed droop strategy utilized in the control system of each phase of DG converters. Based on the proposed triple‐droop control strategy, the real power sharing in an AC low‐voltage microgrid is significantly improved via P–V control strategy and the reactive power sharing accuracy is enhanced via Q–f control strategy. By this method, the amplitude of the output voltage of each phase of the converters is determined based on the amount of load connected to that phase. In addition, the efficiency of the microgrid is increased due to the circulating current reduction between DGs. A virtual impedance concept is also utilized to improve the accuracy of the proposed power sharing method. The feasibility and effectiveness of the proposed strategy are validated using MATLAB/SIMULINK software for International Council for Large Electric Systems (CIGRE) low‐voltage distribution network benchmark.
Co‐simulation platform for integrated real‐time power system emulation and wide area communication
Authors: Adewole Adeyemi Charles , Tzoneva Raynitchka
Published: January 2017

Phasor measurement units (PMUs) are increasingly being deployed in electric power systems in an attempt to improve grid reliability and make the grid smarter through real‐time wide area situational awareness, monitoring, protection and control applications. PMU‐based applications require communication networks in the transmission of synchrophasor measurements from the substations to the control centres. However, the quality‐of‐service of these synchrophasor measurements are not guaranteed when transmitted over a global wide area network especially in the presence of non‐deterministic communication network conditions. This study presents the design, development, and integration of an IEEE Std. C37.118‐based co‐simulation platform comprising of power system hardware‐in‐the‐loop simulations using the real‐time digital simulator interfaced to a communication network. The impact of adverse communication network conditions such as latency, packet losses, and corruption on the exchange of data using the co‐simulation platform and their impact on a centralised wide area monitoring, protection, and control (WAMPAC) system was investigated with software‐in‐the‐loop simulations. Moreover, the maximum allowable adverse communication conditions are quantified with respect to the WAMPAC applications during emergency conditions.
Optimal distributed generation allocation for reactive power control
Authors: Kim Insu
Published: January 2017

One of the main concerns of utilities is to minimise voltage variations along their feeders when they enhance their networks by various distributed generation (DG) systems that have uncertainty in their output. Furthermore, such DG systems can provide reactive power to the grid. Thus, the objective of this study is to optimally allocate locations and capacities of DG systems, particularly photovoltaic systems in this study, on distribution networks that host DG inverters with the capability of reactive power control, in other words, Volt/Var management and control. For this purpose, this study proposes a hybrid method based on optimal reactive power control and genetic algorithms. The proposed method is verified in well‐known test feeders.
Minimum frequency estimation of power system considering governor deadbands
Authors: Chengwei Fan , Xiaoru Wang , Yufei Teng , Wencheng Wu
Published: January 2017

The extensive existence of governor deadband has a significant influence on the minimum frequency of power system after a disturbance. However, the strong nonlinearity of deadband makes it difficult to quantify its impact on the frequency response. For this end, the backlash non‐linearity is adopted to represent for the governor with deadband. The non‐linear characteristics of governor with deadband are thus well approximated. The describing function method is applied to linearise the backlash non‐linearity. Then a first‐order model of governor system is derived to consider the deadband effect quantitatively. Minimum frequency estimation algorithm is proposed based on the first‐order model. The proposed algorithm is effective to reflect the effects of various widths of deadbannd on the minimum value of frequency. Case study is conducted to prove its adequate performance in minimum frequency estimation with a practical power grid in China.
Analytic model for network resource management between ISPs and users
Authors: Lolaee Hossein , Akhaee Mohammad Ali
Published: January 2017

Fixed communication provider is a consortium of internet service providers (ISPs) in which users can switch easily and freely between their ISPs. To increase the QoS of the ISPs, the authors propose a two‐class service model. ISPs divide their available bandwidth into two parts to provide their end users with optimal services. One dedicated to primary users, and the other for secondary users. Primary users are those who pay more and thus, expect dedicated bandwidth that is always available. Secondary services are provided by ISPs for the other users who cannot afford the dedicated bandwidth. In this study, by defining the utility functions for both user types, the authors aim at dividing the ISP bandwidth between these two services such that the utility function of the users is maximised. Since the primary users do not always use the maximum bandwidth, an algorithm is proposed for ISPs to estimate the primary users’ required bandwidth in each time segment based on the previous segments. Based on this estimate, the expected bandwidth is dedicated to the primary users, and the remaining bandwidth is devoted to the secondary users to improve the quality of service. On the other hand, an ISP is penalised if it fails to provide the primary users with the required bandwidth mentioned in their contract. Therefore, there exists a trade‐off between the conservative estimation of the primary users’ rate, the QoS of the secondary users and the achieved utility of the ISPs.
Mutual coherence enhancement in coupled lasers
Authors: Kelleher Bryan , Quinn Gerard
Published: January 2017

Experimentally, mutually coupled quantum dot lasers demonstrate a greatly reduced modal linewidth when mutually phase‐locked. The authors investigate this phenomenon theoretically. Specifically, they examine a delay differential equation coupled phase model and use it to find the laser linewidth in several configurations. The numerical results are in excellent agreement with previously reported experimental findings. They show that while the model predicts a restoring force on the phase difference of the coupled lasers, this translates to an effective restoring force on the individual laser phases. The phenomenon should be robust to changes in device type and in particular for modern, integrated coupled lasers.
Resonance damping in array cable systems by wind turbine active filtering in large offshore wind power plants
Authors: Kocewiak Łukasz Hubert , Kramer Birte Laudal Øhlenschlæger , Holmstrøm Ole , Jensen Kim Høj , Shuai Lei
Published: January 2017

The application of active filtering in large offshore wind power plants (WPPs) is presented in this study. The harmonic challenges such as sources of harmonic emission and resonances are identified and briefly explained. Also modern remedial harmonic mitigation methods as of active filtering are described and their application in real‐life WPP systems demonstrated. It is underlined that WPP components such as widespread medium‐voltage cable system and offshore grid transformers can introduce significant low‐frequency parallel resonances which can cause a significant harmonic voltage distortion at the point of common coupling. Active filtering in modern grid‐side converters used in wind turbines is applied simultaneously keeping sufficient harmonic/noise rejection. Extensive harmonic stability studies are also shown to prove the overall system robustness.
Characterisation of interaction in an offshore AC grid with large WPPs and VSC‐HVDCs
Authors: Shah Rakibuzzaman , Barnes Mike , Preece Robin
Published: January 2017

To exploit the full and flexible capability of offshore voltage‐sourced converter high‐voltage DC (VSC‐HVDC) lines, interaction studies in the offshore AC grid are required but are not well understood or reported. This study examines the interaction dynamics of an offshore AC grid for interconnecting large wind power plants (WPPs). The conventional eigenvalue analysis method has limitations which make the interaction analysis of such systems difficult. Hence, in this study, an impedance‐based analytical approach is employed to investigate the interaction phenomena. The impedance model of a VSC‐HVDC converter for both direct and vector control with outer and droop controls are derived along with the impedance model of the full‐converter wind generator. The interaction dynamics of the offshore grid is predicted through the well‐established Nyquist criteria and is validated using time‐domain simulations. The analysis shows that the system stability is decidedly influenced by the control configurations and tuning of the VSC‐HVDC lines.
Application of the multi‐scale enveloping spectrogram to detect weak faults in a wind turbine gearbox
Authors: Ma Zhiyong , Teng Wei , Liu Yibing , Wang Dameng , Kusiak Andrew
Published: January 2017

The gearbox of a wind turbine involves multiple rotating components, each having a potential to be affected by a fault. Detecting weak faults of these components with traditional demodulation analysis is challenging. Multi‐scale enveloping spectrogram (MuSEnS) decomposes a vibration signal into different frequency bands while simultaneously generating the corresponding envelope spectra. In this study, a MuSEnS‐based diagnosis approach is applied to detect faults affecting the intermediate stage of a gearbox installed in an operating wind turbine. The MuSEnSs of 12 vibration channels have allowed to identify multiple fault features, including the weak fault of the big gear on the sun shaft. The effectiveness of the proposed fault diagnosis approach has been tested with industrial data and the faults themself have been confirmed with the disassembled gears.
Probabilistic transmission expansion planning considering distributed generation and demand response programs
Authors: Hejeejo Rashid , Qiu Jing
Published: January 2017

Transmission expansion planning (TEP) is generally determined by peak demands. To improve the efficiency and sustainability of energy systems, attention has been paid to demand response programs (DRPs) and distributed generation (DG). DRPs and DG will also have significant impacts on the controllability and economics of power systems, from short‐term scheduling to long‐term planning. In this study, a non‐linear economic design for responsive loads is introduced, based on the price flexibility of demand and the customers’ benefit function. Moreover, a probabilistic multi‐objective TEP model which considers DRPs is also proposed. A probabilistic analysis method, the so‐called Monte–Carlo simulation method, is implemented to handle the uncertainty of the loads, DRPs and DG in the TEP problems. Due to the problems’ non‐convex formulations, a non‐dominated sorting differential evolution program is used to solve the TEP problems. The proposed TEP model can find the optimal trade‐off between transmission investment and demand response expenses. The planning methodology is then demonstrated on an IEEE 118‐bus system in order to show the feasibility of the proposed algorithm.
CSVE radar: high‐range‐resolution radar using compressive sensing and virtual expanding technique
Authors: Zhang Li , Li Baoliang , Xie Ning , Wang Hui
Published: January 2017

Range estimation is an important issue of radar system, and its performance is mainly limited by the transmitting bandwidth. To improve the range resolution, the existing approaches often either occupied wider bandwidth or employed some non‐linear techniques which cause high complexity. The wider the transmitting bandwidth has not only the more the network resource takes but also the easier the radio frequency interference (RFI) is introduced. The authors propose a new radar system by utilising jointly the compressive sensing (CS) and the proposed virtual expanding technique, referred to as the compressing sensing and virtual expanding (CSVE) radar system. The proposed CSVE radar system not only provides high‐range resolution with low cost by saving transmitting bandwidth but also is robust to the bad effect of the RFI by utilising a pre‐detection phase at the transmitter and a detection phase at the receiver. Simulation results validate the superiority of the proposed CSVE radar system over both the high‐resolution techniques such as Capon, multiple signal classification and matched filter, and the CS step‐frequency radar system.
Bearings‐only target motion analysis of a highly manoeuvring target
Authors: Kim Jonghoek , Suh Taeil , Ryu Jonha
Published: January 2017

In this study, the authors tackle the bearings‐only target motion analysis problem, which is to estimate the position and velocity of a target using bearing measurements. They consider a target which is highly manoeuvrable. This study introduces the modified range‐parameterised extended Kalman filter (MRPEKF), which consists of a number of independent EKFs, each with a different initial range estimate. The MRPEKF uses the filter re‐initialisation strategy to track a highly manoeuvring target. They further introduce the method to improve the efficiency of the MRPEKF. They verify the effectiveness of their MRPEKF by comparing it with the IMM KF using simulations.
Estimation of the total rotational velocity of a non‐cooperative target with a high cross‐range resolution three‐dimensional interferometric inverse synthetic aperture radar system
Authors: Ng Brian W.‐H. , Tran Hai‐Tan , Martorella Marco , Giusti Elisa , Salvetti Federica , Phan An
Published: January 2017

This study reports on a novel technique for the estimation of the target total rotational velocity of a non‐cooperative target. The technique makes use of the second‐order local polynomial Fourier transform to estimate the hitherto unknown component of the velocity vector in the radar line‐of‐sight direction, and three‐dimensional (3D) interferometric inverse synthetic aperture radar (ISAR) imaging the target. The aspect‐independent 3D size and shape of a target – an important metric for automatic target recognition – can thus be estimated. Cross‐range focus in the component 2D ISAR images is also improved in the process. Results obtained from extensive simulations demonstrate the feasibility of the proposed approach.
Performance prediction of adaptive filters for EEG signal
Authors: Ahirwal Mitul Kumar , Kumar Anil , Singh Girish Kumar , Londhe Narendra Digambar
Published: January 2017

A methodology for predicting the performance of algorithm in terms of fidelity parameters is introduced. Algorithm performance is measured in terms of space and time complexities required to solve a particular problem. The proposed approach correlates the performance with input data and output results. Initial theory of performance model generation is based on polynomial regressing and curve fitting of least mean square (LMS) algorithm for adaptive filtering. Testing and validation of the generated model has been done through the coefficient of determination parameters calculated over interpolation and extrapolation results. Other measures like adjusted R2, sum of square error and mean square error are also reported. Overall study is summarised in form of algorithm, and is tested with LMS and recursive LMS algorithm of adaptive filtering applied over electroencephalography/event related potentials (EEG/ERP) noise removal to build up relation between input signal‐to‐noise ratio (SNR) and output fidelity parameters (like output SNR and correlation (r)).
Improved condition monitoring technique for wind turbine gearbox and shaft stress detection
Authors: Salem Abdulwahed , Abu‐Siada Ahmed , Islam Syed
Published: January 2017

Condition monitoring has been widely used to detect mechanical and electrical faults of wind turbine in order to avoid any potential catastrophic failures, reduce operational and maintenance cost, and enhance the reliability and availability of the equipment. Although several papers about wind turbine condition monitoring can be found in the literatures, adopting a reliable and cost‐effective technique for wind turbines that usually experience severe mechanical stress due to the harsh weather conditions they are exposed to is still challenging. Although statistical studies show that gearbox failure rate is low, the resulted downtime and the replacement or repairing cost is substantial. This study introduces an improved technique to monitor the condition of the wind turbine gearbox based on gearbox vibration and shaft torque signatures analyses. In this context, a test rig that emulates real wind turbine operation has been developed to analyse the behaviour of wind turbine under various mechanical fault levels. Shaft torque and mechanical vibration signals are detected using high‐resolution sensors and are analysed using two signal processing techniques: wavelet and order analyses to examine the impact of investigated fault levels on the wind turbine drive train. Both signal processing techniques are compared based on their sensitivity to detect incipient fault levels.
Performance improvement of metal–oxide arrester for VFTs
Authors: Kannadasan Raju , Valsalal Prasad , Jayavel Ramasamy
Published: January 2017

Gas insulated substation generates very fast transient overvoltages (VFTOs) in power systems because of disconnector switching operations. The present design of metal–oxide arrester may not be effective against these VFTs and so the arrester fails to operate under VFTO. At this point, it becomes essential to improve the electrical behaviour of arrester. Some of the possible measures for improving the electrical behaviour of arrester blocks are the procurement of higher‐voltage gradient, reduction of arrester capacitive effect and reduction in the time lag between residual voltage and current surge. With this background, the microstructural and electrical parameters of arrester block are modified by doping scandium trioxide with basic composition and the samples are prepared using different sintering processes. Subsequently, the voltage gradient, capacitance and the time lag are found for the prepared samples. The performance of new arrester blocks are investigated against VFTO and the results are compared with conventional arrester blocks. From that, it is perceived that the new arrester samples have improved parameters and might be used for protection of power system against VFTO.
Peripheral arterial disease screening for hemodialysis patients using a fractional‐order integrator and transition probability decision‐making model
Authors: Wu Jian‐Xing , Li Chien‐Ming , Chen Guan‐Chun , Ho Yueh‐Ren , Lin Chia‐Hung
Published: January 2017

Atherosclerosis and resultant peripheral arterial disease (PAD) are common complications in patients with type 2 diabetes mellitus or end‐stage renal disease and in elderly patients. The prevalence of PAD is higher in patients receiving haemodialysis therapy. For early assessment of arterial occlusion using bilateral photoplethysmography (PPG), such as changes in pulse transit time and pulse shape, bilateral timing differences could be used to identify the risk level of PAD. Hence, the authors propose a discrete fractional‐order integrator to calculate the bilateral area under the systolic peak (AUSP). These indices indicated the differences in both rise‐timing and amplitudes of PPG signals. The dexter and sinister AUSP ratios were preliminarily used to separate the normal condition from low/high risk of PAD. Then, transition probability‐based decision‐making model was employed to evaluate the risk levels. The joint probability could be specified as a critical threshold, < 0.81, to identify the true positive for screening low or high risk level of PAD, referring to the patients’ health records. In contrast to the bilateral timing differences and traditional methods, the proposed model showed better efficiency in PAD assessments and provided a promising strategy to be implemented in an embedded system.
An assembly oriented design and optimization approach for mechatronic system engineering
Authors: Marconnet Bertrand , Demoly Frédéric , Monticolo Davy , Gomes Samuel
Published: January 2017

Today, companies involved in product development in the “Industry 4.0” era, need to manage all the necessary information required in the product entire lifecycle, in order to optimize as much as possible the product-process integration. In this paper, a Product Lifecycle Management (PLM) approach is proposed, in order to facilitate product-process information exchange, by considering design constraints and rules coming from DFMA (Design For Manufacturing and Assembly) guidelines. Indeed, anticipating these manufacturing and assembly constraints in product design process, reduces both costs and Time To Market (TTM), and avoids to repeat mistakes. The paper details the application of multi-objective optimization algorithms after considering DFMA constraints in a PLM approach. A case study using an original mechatronic system concept is presented, and improved by considering product-process integrated design, optimization and simulation loops, using numerical optimization and FEM (Finite Element Method) methods and tools.
Discoid Lateral Meniscus
Authors: Dai Wen-Li , Zhang Hua , Zhou Ai-Guo , Zhang Gang , Zhang Jian
Published: January 2017

Partial and total meniscectomies are the most common treatments for patients with discoid lateral meniscus (DLM). We conducted this study to quantitatively assess and compare the outcomes of partial and total meniscectomies for DLM. We also assessed whether the outcomes differed by the type of DLM, duration of follow-up, and age of patients. We searched PubMed, Embase, and the Cochrane database to identify relevant studies that reported outcomes, including Ikeuchi grade, the International Knee Documentation Committee (IKDC) Subjective Knee score, Lysholm score, or failure rate, in patients who underwent partial and total meniscectomies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for dichotomous outcomes, whereas mean difference and 95% CIs were calculated for continuous outcomes. Fifteen studies met the inclusion criteria. The overall rate of excellent (E) or good (G) postoperatively was 85.5% (95% CI: 79.5–91.5%). The E or G rate of partial meniscectomy was significantly higher than that of total meniscectomy (OR= 1.97, 95% CI: 1.03–3.75, p = 0.038). Besides, patients younger than 20 years had a significantly higher E or G rate than those older than 20 years. (OR = 3.12, 95% CI: 1.18–8.23, p = 0.022). We also found the E or G rate tended to decrease from short- to long-term follow-up. Our systematic review and meta-analysis showed that that partial meniscectomy could achieve better outcomes compared with total meniscectomy for DLM patients.
Cavernous Sinus Involvement by Pituitary Adenomas: Clinical Implications and Outcomes of Endoscopic Endonasal Resection
Authors: Ajlan Abdulrazag , Achrol Achal , Feroze Abdullah , Westbroek Erick , Hwang Peter , Harsh Griffith , Albakr Abdulrahman
Published: January 2017

Background Parasellar invasion of pituitary adenomas (PAs) into the cavernous sinus (CS) is common. The management of the CS component of PA remains controversial.

Objective The objective of this study was to analyze CS involvement in PA treated with endoscopic endonasal approaches, including incidence, surgical risks, surgical strategies, long-term outcomes, and our treatment algorithm.

Methods We reviewed a series of 176 surgically treated PA with particular attention to CS involvement and whether the CS tumor was approached medial or lateral to the internal carotid artery.

Results The median duration of follow-up was 36 months. Macroadenomas and nonfunctional adenomas represented 77 and 60% of cases, respectively. CS invasion was documented in 23% of cases. CS involvement was associated with a significantly diminished odds of gross total resection (47 vs. 86%, odds ratio [OR]: 5.2) and increased the need for subsequent intervention (4 vs. 40%, OR: 14.4). Hormonal remission was achieved in 15% of hormonally active tumors. Rates of surgical complication were similar regardless of CS involvement.

Conclusion Our tailored strategy beginning with a medial approach and adding lateral exposure as needed resulted in good outcomes with low morbidity in nonfunctional adenomas. Functional adenomas involving the CS were associated with low rates of hormonal remission necessitating higher rates of additional treatment.
Early Commencement of Enteral Feeds in Gastroschisis: A Systematic Review of Literature
Authors: Dama Madhuri , Rao Uday , Gollow Ian , Bulsara Max , Rao Shripada
Published: January 2017

Introduction There are no evidence-based strategies to improve feed tolerance in gastroschisis. Early commencement of enteral feeds (CEF) is known to improve feed tolerance in preterm infants. It is possible that infants with gastroschisis may also benefit from early CEF.

Objective To conduct a systematic review to evaluate the relationship between time of CEF, and time to reach full enteral feeds (FEF), duration of parenteral nutrition (PN), and duration of hospital stay (HS).

Methods PubMed, EMBASE, Cochrane CENTRAL, and relevant conference abstracts were searched in December 2015. Studies of any design reporting on time to CEF and one or more of the outcomes of interest were included. Meta-regression analysis was conducted to find the association between time to CEF and the outcomes of interest.

Results There were no randomized controlled trials (RCTs) comparing early (≤7 days from birth) versus delayed (>7 days) CEF. Forty-two observational studies on gastroschisis (4,835 infants) where feed-related information was available were included. Meta-regression results indicated that each day delay in CEF was associated with a delay of an additional 1.4 days (95% confidence interval [CI]: 0.95, 1.85) to FEF, 2.05 days (95% CI: 1.50, 2.59) to the duration of PN, and 1.91 days (95% CI: 1.37, 2.45) to the duration of HS. Sensitivity analysis after excluding studies that provided information exclusively on complex gastroschisis continued to show beneficial effects of early CEF.

Conclusion Early CEF may be associated with early attainment of FEF in gastroschisis. RCTs comparing early versus delayed CEF are needed urgently.
Cannabidiol for the Treatment of Drug-Resistant Epilepsy in Children: Current State of Research
Authors: Evans Victoria , DeMarse Thomas , Febo Marcelo , Johnson Cynthia , Carney Paul , Anderson Christopher
Published: January 2017

The reported effectiveness of these home preparations, especially those with high cannabidiol (CBD) concentrations, has garnered the attention of the medical community. In particular cannabis sativa, known for its lack of a psychoactive effect and high CBD content, has become a target of medical research. The shift in public and political interest to medicinal applications of CBD demands renewed research into its efficacy. Pediatric populations in particular stand to benefit significantly from a better understanding of the safety and efficacy of this novel treatment. This review discusses the current state of CBD research and identifies areas that require further investigation as they pertain to pediatric epilepsy populations. It will especially cover those suffering from refractory epilepsies for which other methods of remediation have not sufficed.
Genome Editing Tools und ihr Einsatz in der experimentellen Augenheilkunde
Authors: Yanik M. , Wende W. , Stieger K.
Published: January 2017

Neue molekularbiologische Werkzeuge revolutionieren zurzeit die Genomchirurgie (genome editing) mit weitreichendem Einfluss auch auf die experimentelle Augenheilkunde. Neben den bereits etablierten Systemen wie den Zinkfingernukleasen (ZFN) oder Transcription-activator-like-Effector-Nukleasen (TALEN) sind es insbesondere die CRISPR-/Cas-Systeme (CRISPR: clustered regularly interspaced short palindromic repeats; Cas: CRISPR-associated), die überraschend einfach einen gezielten und präzisen Schnitt im Genom lebender Zellen ermöglichen. Dieser DNA-Doppelstrangbruch wird in der Zelle mittels NHEJ (non-homologous end joining) oder HDR (homology directed repair) repariert und kann ausgenutzt werden, um ein defektes Gen zu deaktivieren oder mithilfe einer korrekten Gensequenz zu reparieren. Die Genome-Editing-Technologie eröffnet damit bisher ungeahnte Möglichkeiten in der Grundlagenforschung, Biotechnologie, biomedizinischen Forschung bis hin zu ersten klinischen Anwendungen. Neurodegenerative Erkrankungen der Netzhaut stehen dabei aufgrund der guten Zugänglichkeit und des Immunprivilegs des Auges mit im Fokus des Interesses von Forschern und Firmen.
Injektionsstrategien bei der Anwendung intravitrealer VEGF-Inhibitoren: „Pro Re Nata versus Treat and Extend“
Authors: Hufendiek K. , Pielen A. , Framme C.
Published: January 2017

Das Ziel dieses Artikels ist es, einen Überblick zu geben über verschiedene Strategien zur Verwendung von PRN- und T&E-Therapieschemata (PRN: pro re nata; T&E: treat and extend) mit intravitrealen Anti-VEGF-Medikamenten (Bevacizumab, Ranibizumab oder Aflibercept) bei Patienten mit Netzhauterkrankungen wie neovaskulärer AMD, diabetischem Makulaödem und Makulaödem aufgrund von retinalen Venenverschlüssen. Der Schwerpunkt liegt dabei darauf, die Wirksamkeit und die Visusergebnisse des PRN- und des T&E-Regimes in Korrelation mit den wichtigsten Zulassungsstudien und Studien basierend auf den derzeit verfügbaren Daten vorzulegen. Wir diskutieren auch die Vor- und Nachteile der beiden Therapieregimes sowie die Überwachung und Behandlung der Krankheitsaktivität einschließlich der Behandlungsintervalle und Injektionsfrequenz. Derzeit gibt es ein zunehmendes Interesse, ein Regime zu etablieren, das die besten Visusergebnisse bei reduzierter Injektionsfrequenz und konsekutiv geringerer Belastung der Patienten durch individualisierte Behandlungsintervalle mit Minimierung der Anzahl der Klinikbesuche und der entstehenden Kosten bietet. Studien haben gezeigt, dass das PRN-Regime im realen Klinikalltag keine optimalen Visusergebnisse liefert. PRN erfordert häufige Arztbesuche, um den Krankheitsstatus zu kontrollieren und intravitreale Behandlung bei Bedarf reaktiv zu indizieren. Individualisierte T&E-Regimes können das Visusergebnis mit signifikant weniger Kontrolluntersuchungen verbessern im Gegensatz zu Therapieschemata mit einer monatlichen Applikation oder einem PRN-Regime.
On the embedding of Weyl manifolds
Authors: Avalos R. , Dahia F. , Romero C.
Published: January 2017

We discuss the possibility of extending different versions of the Campbell-Magaard theorem, which have already been established in the context of semi-Riemannian geometry, to the context of Weyl’s geometry. We show that some of the known results can be naturally extended to the new geometric scenario, although new difficulties arise. In pursuit of solving the embedding problem, we have obtained some no-go theorems. We also highlight some of the difficulties that appear in the embedding problem, which are typical of the Weylian character of the geometry. The establishing of these new results may be viewed as part of a program that highlights the possible significance of embedding theorems of increasing degrees of generality in the context of modern higher-dimensional space-time theories.