bluuebunny/crossref_metadata_2025 huggingface dataset:
Redox-responsive supramolecular amphiphiles based on a pillar[5]arene for enhanced photodynamic therapy
Authors: Chen Ye , Rui Leilei , Liu Lichao , Zhang Weian
Published: April 2016

Supramolecular amphiphiles based on a pillar[5]arene with enhanced photodynamic therapy have been fabricated.
An efficient catalytic synthesis and characterization of new styryl-ferrocenes and their trans-π-conjugated organosilicon materials
Authors: Majchrzak M. , Kostera S. , Grzelak M. , Marciniec B. , Kubicki M.
Published: April 2016

A selective and efficient catalytic method for the synthesis of new styryl-π-conjugated silyl-ferrocenes in a stereoselective manner is presented.
Nioplexes encapsulated in supramolecular hybrid biohydrogels as versatile delivery platforms for nucleic acids
Authors: Grijalvo Santiago , Puras Gustavo , Zárate Jon , Pons Ramon , Pedraz Jose Luis , Eritja Ramon , Díaz David Díaz
Published: April 2016

Supramolecular hydrogels based on N-protected phenylalanine (Fmoc–Phe–OH) were used to encapsulate non-ionic surfactant vesicles (niosomes).
Highly planar thieno[3,2-b]thiophene-diketopyrrolopyrrole-containing polymers for organic field-effect transistors
Authors: Liu Xiaotong , Huang Jianyao , Xu Jie , Gao Dong , Zhang Weifeng , Shi Keli , Yu Gui
Published: April 2016

Two novel thieno[3,2-b]thiophene-flanked diketopyrrolopyrrole-based copolymers (PTTDPPTVT and PTTDPPSVS) with high planarity were synthesized and studied as semiconductors in OFETs.
Designing a sulphonic acid functionalized benzimidazolium based poly(ionic liquid) for efficient adsorption of hexavalent chromium
Authors: Khiratkar Avinash Ganesh , Senthil Kumar S. , Bhagat Pundlik Rambhau
Published: April 2016

Herein, the facile synthesis of sulphonic acid functioned benzimidazolium based poly(ionic liquid) (SBPIL) is reported for the first time and we investigated its efficacy towards the removal of Cr(vi).
Preparation of thiol-functionalized magnetic sawdust composites as an adsorbent to remove heavy metal ions
Authors: Gan Wentao , Gao Likun , Zhan Xianxu , Li Jian
Published: April 2016

TF-MS could be used to remove heavy metal ions from an aqueous solution and be separated conveniently from the solution with the help of an external magnet.
Influence of additives on microstructure, mechanical and tribological properties of nanocrystalline Zn–Ni coatings in a novel alkaline bath
Authors: Feng Zhongbao , Ren Lili , Zhang Jinqiu , Yang Peixia , An Maozhong
Published: April 2016

Nanocrystalline Zn–Ni coatings with excellent wear resistance can be obtained from a novel alkaline bath. Meanwhile, the effects of additives and Ni content in deposits on wear behaviors and the wear mechanism of Zn–Ni coatings are investigated.
Nitrogen-doped TiO2 microspheres with hierarchical micro/nanostructures and rich dual-phase junctions for enhanced photocatalytic activity
Authors: Wang Wei , Liu Yu , Qu Jifa , Chen Yubo , Shao Zongping
Published: April 2016

We successfully synthesized microspherical nitrogen-doped TiO2 with hierarchical nano/microstructures, rich anatase TiO2–TiO2(B) phase junctions and a reduced band gap for the photo-degradation of dyes with improved photocatalytic activity.
Ultrahigh humidity sensitivity of NaCl-added 3D mesoporous silica KIT-6 and its sensing mechanism
Authors: He Xiaowei , Geng Wangchang , Zhang Baoliang , Jia Lemin , Duan Libing , Zhang Qiuyu
Published: April 2016

NaCl-added mesoporous silica KIT-6 was prepared by a facile grind method. This material displayed ultrahigh humidity sensitivity. Its impedance changed by more than five orders of magnitude over the whole humidity range (11%~95% RH).
Growth kinetics of colloidal Ge nanocrystals for light harvesters
Authors: Cosentino Salvatore , Torrisi Giacomo , Raciti Rosario , Zimbone Massimo , Crupi Isodiana , Mirabella Salvo , Terrasi Antonio
Published: April 2016

Representation of growth kinetics mechanisms that strongly control synthesis and final dimension of colloidal nanocrystals.
A new cost-effective Ru-chloramphenicol base derivative catalyst for the asymmetric transfer hydrogenation/dynamic kinetic resolution of N-Boc α-amino-β-ketoesters and its application to the synthesis of the chiral core of vancomycin
Authors: Wang Xinlong , Xu Lingjun , Xiong Fangjun , Wu Yan , Chen Fener
Published: April 2016

Herein we describe the application of Ru-chloramphenicol base complexes catalyzed highly diastereo- and enantioselective transfer hydrogenation of N-Boc α-amino-β-ketoesters for the asymmetric synthesis of anti-N-Boc-β-hydroxy-α-amino esters.
Fabrication of a heated electrode modified with a thiol-functionalized ionic liquid for electrochemical/electrochemiluminescence sensors
Authors: Chen Yiting , Li Yanxia , Jiang Linqin , Huang Lu , Lin Qi , Chen Guonan
Published: April 2016

A new heated thiol-functionalized ionic liquid (TFIL)/Au composite electrode, which possessed the advantages of a heated electrode technique and ionic liquids (ILs), was designed and fabricated in this study.
Ultrathin N-rich boron nitride nanosheets supported iron catalyst for Fischer–Tropsch synthesis
Authors: Wu Jianghong , Qin Li , Wang Conghui , Lv Baoliang , Wang Liancheng , Chen Jiangang , Xu Yao
Published: April 2016

The Fe/BNNSs catalysts were firstly fabricated for the Fischer–Tropsch synthesis, which exhibited appreciable FTS activity, selectivity and good stability over 270 h.
Facile fabrication of sea buckthorn biocarbon (SB)@α-Fe2O3 composite catalysts and their applications for adsorptive removal of doxycycline wastewater through a cohesive heterogeneous Fenton-like regeneration
Authors: Zhang Xia , Bai Bo , Wang Honglun , Suo Yourui
Published: April 2016

Novel SB@α-Fe2O3 composite catalysts were fabricated through a simple thermal conversion process from SB@β-FeOOH precursor, which maintained good adsorption capacity after five successive adsorption/heterogeneous Fenton-like regeneration cycles.
Injectable hydrogels by inclusion complexation between a three-armed star copolymer (mPEG-acetal-PCL-acetal-)3 and α-cyclodextrin for pH-triggered drug delivery
Authors: Hu Jian , Zhang Mingzu , He Jinlin , Ni Peihong
Published: April 2016

Novel acid-cleavable and injectable supramolecular hydrogels based on inclusion complexes between the acid-cleavable star copolymer (mPEG-a-PCL-a-)3 and α-CD were prepared, and used as controlled drug delivery depots.
Fabrication of Au/CNT hollow fiber membrane for 4-nitrophenol reduction
Authors: Zhang Qi , Fan Xinfei , Wang Hua , Chen Shuo , Quan Xie
Published: April 2016

An Au/CNT hollow fiber membrane is synthesized for the reduction of 4-nitrophenol to 4-aminophenol.
A novel heteroacene 2-(perfluorophenyl)-1H-imidazo[4,5-b]phenazine for selective sensing of picric acid
Authors: Gu Pei-Yang , Wang Chengyuan , Nie Lina , Long Guankui , Zhang Qichun
Published: April 2016

A novel chemosensor probe (PFIPZ) has been successfully synthesized and can identify picric acid over other electron-deficient compounds or strong acids.
Quantification of cysteine hydropersulfide with a ratiometric near-infrared fluorescent probe based on selenium–sulfur exchange reaction
Authors: Han Xiaoyue , Yu Fabiao , Song Xinyu , Chen Lingxin
Published: April 2016

A ratiometric near-infrared fluorescent probe based on a selenium–sulfur exchange reaction to quantify cysteine hydropersulfide in living cells and hepatic carcinoma rats.
Application of nanodiamonds in Cu(ii)-based rhodamine B probes for NO detection and cell imaging
Authors: Liu Bin , Hu Xiangquan , Chai Jie , Zhu Junyao , Yang Binsheng , Li Yingqi
Published: April 2016

A nanodiamond-conjugated rhodamine fluorescent sensor for Cu(ii) which could then be developed as an excellent NO selective fluorescent particle.
Thermally controlled dual-mode display media with red-green-blue coloration and fluorescence via energy transfer between emission materials and leuco dyes
Authors: Ogasawara Kouki , Nakamura Kazuki , Kobayashi Norihisa
Published: April 2016

Thermo-responsive multifunctional composite materials enabling red-green-blue (RGB) control of both emission and reflection were fabricated.
The role of phosphatidylinositol-transfer proteins at membrane contact sites
Authors: Selitrennik Michael , Lev Sima
Published: April 2016

Phosphatidylinositol-transfer proteins (PITPs) have been initially identified as soluble factors that accelerate the monomeric exchange of either phosphatidylinositol (PI) or phosphatidylcholine (PC) between membrane bilayers in vitro. They are highly conserved in eukaryotes and have been implicated in different cellular processes, including vesicular trafficking, signal transduction, and lipid metabolism. Recent studies suggest that PITPs function at membrane contact sites (MCSs) to facilitate the transport of PI from its synthesis site at the endoplasmic reticulum (ER) to various membrane compartments. In this review, we describe the underlying mechanism of PITPs targeting to MCSs, discuss their cellular roles and potential mode of action.
The integrin αvβ6: a novel target for CAR T-cell immunotherapy?
Authors: Whilding Lynsey M. , Vallath Sabari , Maher John
Published: April 2016

Immunotherapy of cancer using chimeric antigen receptor (CAR) T-cells is a rapidly expanding field. CARs are fusion molecules that couple the binding of a tumour-associated cell surface target to the delivery of a tailored T-cell activating signal. Re-infusion of such genetically engineered T-cells to patients with haematological disease has demonstrated unprecedented response rates in Phase I clinical trials. However, such successes have not yet been observed using CAR T-cells against solid malignancies and this is, in part, due to a lack of safe tumour-specific targets. The αvβ6 integrin is strongly up-regulated in multiple solid tumours including those derived from colon, lung, breast, cervix, ovaries/fallopian tube, pancreas and head and neck. It is associated with poorer prognosis in several cancers and exerts pro-tumorigenic activities including promotion of tumour growth, migration and invasion. By contrast, physiologic expression of αvβ6 is largely restricted to wound healing. These attributes render this epithelial-specific integrin a highly attractive candidate for targeting using immunotherapeutic strategies such as CAR T-cell adoptive immunotherapy. This mini-review will discuss the role and expression of αvβ6 in cancer, as well as its potential as a therapeutic target.
The role of the HGF/Met axis in mesothelioma
Authors: Thayaparan Thivyan , Spicer James F. , Maher John
Published: April 2016

Malignant mesothelioma is an asbestos-related cancer that occurs most commonly in the pleural space and is incurable. Increasing evidence suggests that aberrant receptor tyrosine kinase (RTK)-directed signalling plays a key role in the pathogenesis of this cancer. In the majority of mesotheliomas, up-regulated expression or signalling by Met, the receptor for hepatocyte growth factor (HGF) can be demonstrated. Following binding of ligand, Met relays signals that promote cell survival, proliferation, movement, invasiveness, branching morphogenesis and angiogenesis. Here we describe the HGF/Met axis and review the mechanisms that lead to the aberrant activation of this signalling system in mesothelioma. We also describe the cross-talk that occurs between HGF/Met and a number of other receptors, ligands and co-receptor systems. The prevalent occurrence of HGF/Met dysregulation in patients with mesothelioma sets the scene for the investigation of pharmaceutical inhibitors of this axis. In light of the inter-relationship between HGF/Met and other ligand receptor, combinatorial targeting strategies may provide opportunities for therapeutic advancement in this challenging tumour.
Novel targets and interaction partners of mutant p53 Gain-Of-Function
Authors: Aschauer Lydia , Muller Patricia A.J.
Published: April 2016

In many human cancers p53 expression is lost or a mutant p53 protein is expressed. Over the past 15 years it has become apparent that a large number of these mutant p53 proteins have lost wild type function, but more importantly have gained functions that promote tumorigenesis and drive chemo-resistance, invasion and metastasis. Many researchers have investigated the underlying mechanisms of these Gain-Of-Functions (GOFs) and it has become apparent that many of these functions are the result of mutant p53 hijacking other transcription factors. In this review, we summarize the latest research on p53 GOF and categorize these in light of the hallmarks of cancer as presented by Hannahan and Weinberg.
New molecular mechanisms of inter-organelle lipid transport
Authors: Drin Guillaume , von Filseck Joachim Moser , Čopič Alenka
Published: April 2016

Lipids are precisely distributed in cell membranes, along with associated proteins defining organelle identity. Because the major cellular lipid factory is the endoplasmic reticulum (ER), a key issue is to understand how various lipids are subsequently delivered to other compartments by vesicular and non-vesicular transport pathways. Efforts are currently made to decipher how lipid transfer proteins (LTPs) work either across long distances or confined to membrane contact sites (MCSs) where two organelles are at close proximity. Recent findings reveal that proteins of the oxysterol-binding protein related-proteins (ORP)/oxysterol-binding homology (Osh) family are not all just sterol transporters/sensors: some can bind either phosphatidylinositol 4-phosphate (PtdIns(4)P) and sterol or PtdIns(4)P and phosphatidylserine (PS), exchange these lipids between membranes, and thereby use phosphoinositide metabolism to create cellular lipid gradients. Lipid exchange is likely a widespread mechanism also utilized by other LTPs to efficiently trade lipids between organelle membranes. Finally, the discovery of more proteins bearing a lipid-binding module (SMP or START-like domain) raises new questions on how lipids are conveyed in cells and how the activities of different LTPs are coordinated.
When under pressure, get closer: PERKing up membrane contact sites during ER stress
Authors: van Vliet Alexander R. , Agostinis Patrizia
Published: April 2016

The endoplasmic reticulum (ER) is the main hub of cellular Ca2+ signalling and protein synthesis and folding. The ER moreover is the central player in the formation of contact sites with other organelles and structures, including mitochondria, plasma membrane (PM) and endosomes. The most studied of these, the ER–mitochondria contact sites, are crucial regulators of cellular Ca2+ homoeostasis, metabolism and cell death signalling. Protein kinase RNA-like ER kinase (PERK), an ER stress kinase and crucial signalling protein in the unfolded protein response (UPR), was found to be able to orchestrate contact sites between the ER and mitochondria and to be indispensable for the pre-apoptotic trafficking of calreticulin (CRT) at the PM during immunogenic cell death (ICD). Furthermore, PERK has recently been linked with ER and PM contact sites through the mechanism of store-operated Ca2+ entry (SOCE). Here we discuss emerging findings disclosing novel roles of the ER stress sensor PERK in orchestrating inter-organellar communication in the context of ER stress.
Roles for Ca2+ mobilization and its regulation in mast cell functions: recent progress
Authors: Holowka David , Wilkes Marcus , Stefan Christopher , Baird Barbara
Published: April 2016

Ca2+ mobilization in response to cross-linking of IgE bound to its high affinity receptor, FcεRI, on mast cells is central to immune allergic responses. Stimulated tyrosine phosphorylation caused by this cross-linking activates store-operated Ca2+ entry that results in sustained Ca2+ oscillations dependent on Rho family GTPases and phosphoinositide synthesis. Coupling of the endoplasmic reticulum (ER) Ca2+ sensor, stromal interaction molecule 1 (STIM1), to the Ca2+-selective channel, Orai1, is regulated by these elements and depends on membrane organization, both at the plasma membrane and at the ER. Mitochondria also contribute to the regulation of Ca2+ mobilization, and we describe recent evidence that the ER membrane protein vesicle-associated membrane protein-associated protein (VAP) plays a significant role in the coupling between ER and mitochondria in this process. In addition to granule exocytosis, Ca2+ mobilization in these cells also contributes to stimulated outward trafficking of recycling endosomes and to antigen-stimulated chemotaxis, and it is pathologically regulated by protozoan parasitic invasion.
Mitophagy as a stress response in mammalian cells and in respiring S. cerevisiae
Authors: Abeliovich Hagai , Dengjel Jörn
Published: April 2016

The degradation of malfunctioning or superfluous mitochondria in the lysosome/vacuole is an important housekeeping function in respiring eukaryotic cells. This clearance is thought to occur by a specific form of autophagic degradation called mitophagy, and plays a role in physiological homoeostasis as well as in the progression of late-onset diseases. Although the mechanism of bulk degradation by macroautophagy is relatively well established, the selective autophagic degradation of mitochondria has only recently begun to receive significant attention. In this mini-review, we introduce mitophagy as a form of mitochondrial quality control and proceed to provide specific examples from yeast and mammalian systems. We then discuss the relationship of mitophagy to mitochondrial stress, and provide a broad mechanistic overview of the process with an emphasis on evolutionarily conserved pathways.
Ca2+ dialogue between acidic vesicles and ER
Authors: Morgan Anthony J.
Published: April 2016

Extracellular stimuli evoke the synthesis of intracellular second messengers, several of which couple to the release of Ca2+ from Ca2+-storing organelles via activation of cognate organellar Ca2+-channel complexes. The archetype is the inositol 1,4,5-trisphosphate (IP3) and IP3 receptor (IP3R) on the endoplasmic reticulum (ER). A less understood, parallel Ca2+ signalling cascade is that involving the messenger nicotinic acid adenine dinucleotide phosphate (NAADP) that couples to Ca2+ release from acidic Ca2+ stores [e.g. endo-lysosomes, secretory vesicles, lysosome-related organelles (LROs)]. NAADP-induced Ca2+ release absolutely requires organellar TPCs (two-pore channels). This review discusses how ER and acidic Ca2+ stores physically and functionally interact to generate and shape global and local Ca2+ signals, with particular emphasis on the two-way dialogue between these two organelles.
Working With Interpreters to Support Students Who Are English Language Learners
Authors: Langdon Henriette W. , Saenz Terry Irvine
Published: April 2016

The number of English Language Learners (ELL) is increasing in all regions of the United States. Although the majority (71%) speak Spanish as their first language, the other 29% may speak one of as many as 100 or more different languages. In spite of an increasing number of speech-language pathologists (SLPs) who can provide bilingual services, the likelihood of a match between a given student's primary language and an SLP's is rather minimal. The second best option is to work with a trained language interpreter in the student's language. However, very frequently, this interpreter may be bilingual but not trained to do the job.
Intensifying English Vocabulary Instruction for English Language Learners
Authors: Fitton Lisa , Bustamante Kristina Nichole , Wofford Mary Claire , Brown Dana , Gabas Clariebelle , Hoge Rachel , Wood Carla
Published: April 2016

English vocabulary development is a key component of language and literacy development for English language learners (ELLs) living in the United States. With the increase in the number of speech-language pathologists (SLPs) with ELLs on their caseloads, it has become increasingly important for SLPs to be able to facilitate vocabulary growth in ELLs. To assist SLPs working with ELLs in schools, the present paper provides an overview of strategies to enhance English vocabulary instruction for ELLs, drawing on evidence from research with both monolingual and bilingual students. Strategies included are: leveraging the native language, teaching comprehension monitoring, embedding instruction in reading, building morphological awareness, and collaborating with classroom teachers. Specific, effective vocabulary instruction protocols are also briefly overviewed.
Extracting high discrimination and shift invariance features in synthetic aperture radar images
Authors: Zhao Xiaohui , Jiang Yicheng
Published: April 2016

A feature processing technique that is specifically designed for synthetic aperture radar images, where features are extracted with merits of compactness, high discrimination ability, and shift invariance is proposed. To this end, a rich feature set is first constructed with a wealth of discrimination information. Then, the redundancy and dimensionality of the rich feature set are reduced such that a much more compact and efficient feature set can be achieved. Finally, the advantages of the compact feature set are further explored by learning the relationships among features statistically in discriminative fashion. Experimental results show the efficiency of the proposed method.
Flexible practical multi‐band large scale antenna system architecture for 5G wireless networks
Authors: Guan L. , Rulikowski P. , Kearney R.
Published: April 2016

Owing to its promising spectrum utilisation efficiency, large scale antenna system (LSAS) has been identified as one of the key technologies for fifth generation wireless networks. It will be more beneficial when combining LSAS with multi‐band radio for further boosting the network capacity and data throughput. However, this concept dramatically increases the system complexity and cost because of the architectural requirement of many multi‐band RF transceivers. It may even block the way of deploying this technology in the field. Practical multi‐band LSAS architecture is presented, by using newly introduced open‐flow like signal switch unit, the proposed architecture will be physically able to re‐configure its operation modes and to flexibly expand the system seamlessly regarding both RF part and digital part. To proof of concept, a simplified dual RFDAC‐based multi‐band radio transmitter with an FPGA‐based signal switch and an easyto‐use MATLAB‐based graphic user control plane is created.
Optimal time allocation for RF‐powered DF relay‐assisted cooperative communication
Authors: Mishra D. , De S.
Published: April 2016

A decode‐and‐forward (DF) relay‐assisted RF‐powered cooperative communication between an RF energy harvesting source and an information sink is considered. DF relay aids the communication between these two distant wireless nodes by (i) RF energy transfer to the source, and (ii) relaying source data to the sink. To enable efficient RF‐powered delay‐constrained information transfer to the sink under Rayleigh fading, joint global‐optimal time allocations for information and energy transfer are derived. Impact of relay position on throughput and optimality of the analytical solutions are numerically investigated.
Electric‐field‐coupled contactless ID sensor for cm‐level high‐precision positioning item‐level tagging systems
Authors: Jeong M.‐G. , Kim J.‐H. , Bae S.‐H. , Lee W.‐S.
Published: April 2016

To detect multiple identifications (IDs) for cm‐level high‐precision positioning item‐level tagging (ILT) systems in near‐field ultra‐high‐frequency RFID applications, an electric‐field‐coupled multiple ID sensor is presented. The proposed ID sensor consists of four circular electric coupling parts, an impedance‐matching network, and an SP4T switch for position control. By switching the electric‐field‐coupled sensing parts, cm‐level position detection of densely aggregated RFID tags for a small‐sized ILT can be achieved. The sensing distance of the proposed ID sensor is ∼7 mm and its physical size is 50 × 50 mm2 (∼1/7λ0 at 920 MHz).
DLL‐based signal conditioning system for SAW sensor with digital output
Authors: Rottava R.E. , Rangel de Sousa F. , Balashov S.M.
Published: April 2016

The use of a delay‐locked loop (DLL) for conditioning signals from a surface acoustic wave (SAW) sensor is proposed. The system consists of a reference oscillator and a DLL. The signal generated in the reference oscillator is propagated through a sensitive SAW delay line (SAW‐DL). The SAW propagating through this structure has a phase velocity dependent on environmental parameters such as temperature, humidity, mechanical deformation, or analyte concentration. Therefore, the system measures the physical quantity of interest by tracking the delay caused by the sensitive SAW‐DL via a DLL. Fully digital DLL is made use of for the delay‐tracking, which provides the conversion of the environmental parameter being sensed directly to the digital domain. The system is demonstrated through results from behavioural simulation, using a model of an SAW‐DL sensitive to humidity.
Improvements in magnetic field intensity and uniformity for small‐animal MRI through a high‐permittivity material attachment
Authors: Seo J.‐H. , Han S.‐D. , Kim K.‐N.
Published: April 2016

The ultra‐high field (UHF) small‐animal MRI (sa‐MRI) device provides a powerful platform for translational imaging. To achieve a high signal‐to‐noise ratio, as well as sufficient signal homogeneity in abdominal imaging, the RF coil has to be precisely tuned. A novel geometry for a high‐permittivity material (HPM) was designed and integrated into an enlarged (90 mm) birdcage (BC) RF coil. The geometrical design of the HPM attachment was based on a computational calculation, and was compared with the commonly used 72 mm bandpass filter BC coil without any HPM attachments. The resulting RF transmission (|B1+|) map clearly shows that the increased coil diameter led to a decreased |B1+| intensity. However, this loss in field intensity was mitigated by optimally integrating the HPM attachment with the coil. As a result of this attachment, the proposed design exhibits superior |B1+| intensity and uniformity along the main magnetic field z‐direction.
Orthogonal polynomials non‐linearity compensation for a digital VCO‐based ADC
Authors: Zhang Y. , El‐Sankary K.
Published: April 2016

An improved compensation method for an all‐standard‐cell voltage‐controlled oscillator (VCO)‐based ADC is presented in this Letter. The proposed compensation uses closed‐form orthogonal polynomials bases instead of power series ones. With these more powerful bases, the cross interaction between different basis is eliminated which leads to better resolution, lower order of compensation series, and shorter convergence time of the adaptive algorithm.
Extended kernelised correlation filter tracking
Authors: Ruan Yang , Wei Zhenzhong
Published: April 2016

Due to the impressive high‐speed, correlation filters began to receive more attention. In this Letter, a real time target tracking framework based on the kernelised correlation filter is proposed. The framework includes two parts: a boosted fusion feature colour names‐histograms of oriented gradients (CN‐HOG) that consists of CNs and HOG, and a novel fragments‐based tracking algorithm that is robust to partial occlusion. Experiments with the evaluation of state‐of‐the‐art single object trackers show the effectiveness and speed of the proposed method.
Long‐time coherent integration method for high‐speed target detection using frequency agile radar
Authors: Wang Dinghe , Lin Caiyong , Bao Qinglong , Chen Zengping
Published: April 2016

In frequency agile radar (FAR), successive pulses each with different carrier frequencies are used as the transmission waveform. Since the range–Doppler coupling effect of a high‐speed target varies significantly with the carrier frequency, large ranging errors will exist between different pulses. In this case, great distortion of the moving trace in the echo plane will be present after conventional pulse compression. The distortion will defocus the echo energy in the integration process when combining multiple pulses. In addition, for high‐speed targets, the traditional narrowband matched filter will suffer from a decrease in signal‐to‐noise ratio, especially when pulses with large duration or bandwidths are used. A long‐time coherent integration method for the high‐speed target detection using FAR is proposed. The effectiveness is verified by simulation experiments.
Binary polar codes are optimised codes for bitwise multistage decoding
Authors: El‐Khamy M. , Lin H.P. , Lee J.
Published: April 2016

Polar codes are considered the latest major breakthrough in coding theory. Polar codes were introduced by Arıkan in 2008. It is shown that the binary polar codes are the same as the optimised codes for bitwise multistage decoding, which have been discovered before by Stolte in 2002. The equivalence between the techniques used for the constructions and decodings of both codes is established.
Low‐complexity method for primary synchronisation in the third generation partnership project long term evolution downlink system
Authors: Jabbarvaziri Faramarz , Alizadeh Mostafa , Mohammadi Abbas , Abdipour Abdolali
Published: April 2016

In this study, the authors propose a low‐complexity method for symbol synchronisation in the third generation partnership project long term evolution (LTE) downlink system. The authors introduce the lowest sampling frequency of a receiver for synchronisation purposes. Using a low sampling frequency at the receiver means that the digital signal is decimated and a lower number of processing samples is needed. This results in reducing the computational complexity. It is also shown that this advantage comes at the cost of signal‐to‐noise ratio degradation and insertion of a systematic error in synchronisation that can be avoided by choosing a proper decimation factor. A thorough analysis is also conducted for all possible sampling frequencies that reduce the computational complexity of LTE cell search. To show the validity of the authors’ method, they implemented an LTE primary synchroniser in C++ using GNU Radio libraries and prepared a software‐based radio modem, tested in different conditions. Some Monte‐Carlo simulations are carried out to compare the proposed method with other low‐complexity methods. These comparisons show the suggested method is faster than available techniques in literatures.
Two‐stage frequency‐domain oversampling receivers for cyclic prefix orthogonal frequency‐division multiplexing systems
Authors: Yan Yanxin , Gong Yi , Ma Maode
Published: April 2016

Orthogonal frequency‐division multiplexing (OFDM) is a widely adopted technique in most wireless applications. It has been shown that zero padded OFDM (ZP‐OFDM) with frequency‐domain oversampling (FDO) can exhibit better performance than cyclic prefix OFDM (CP‐OFDM) if the whole OFDM symbol is oversampled in the frequency domain. In this study, the authors propose a novel FDO‐based scheme for CP‐OFDM, which consists of two stages. First, the conventional CP‐OFDM receiver is adopted to estimate the transmitted data and channel information. Second, the received symbol is reconstructed to reduce inter‐symbol interference and oversampled in the frequency domain. The proposed scheme combines FDO and symbol reconstruction together, which enables the minimum mean square error (MMSE) and zero forcing (ZF) equalisers to exploit the channel information in high‐dimensional non‐orthogonal subcarrier domain and thus significantly suppress the interference on multipath channels. Simulation results show that the proposed FDO‐MMSE CP‐OFDM receiver can achieve much better bit error rate performance than the traditional CP‐OFDM receiver and is comparable to the ZP‐OFDM receiver with FDO.
Interference alignment with random vector quantisation in device‐to‐device underlaying cellular networks
Authors: Zhang Yang , Zhao Chenglin , Hong Li , Yu Junsheng , Li Shibao
Published: April 2016

In this study, the authors focus on the problem of interference alignment (IA) with random vector quantisation in device‐to‐device (D2D) uplink underlaying cellular networks. For a D2D underlaying system with one cellular network and one D2D local network, they first analyse the leakage interference introduced by limited feedback and, hence, imperfect IA. Then, they derive the exact closed‐form expressions of average sum rate in terms of transmit power for cellular communication and D2D communication. Under such condition, they investigate the adaptive feedback bits allocation schemes to achieve near‐optimal performance of systems with limited feedback including a greedy feedback bits allocation scheme and a waterfilling‐based feedback bits allocation scheme. Finally, simulation results validate their theoretical results and show that significant performance gain can be obtained by allocating feedback bits adaptively.
Algorithm for local input‐to‐state stability analysis
Authors: Qin Boyu , Zhang Xuemin , Ma Jin , Mei Shengwei
Published: April 2016

Compared with global input‐to‐state stability (ISS), the concept of local input‐to‐state stability (LISS) is more practical for engineering applications. In order to reduce the conservativeness and achieve better estimate in LISS analysis, a systematic algorithm for estimating the local region of LISS is proposed in this study. A set description of the convergence region is developed to improve the accuracy of the estimated asymptotic gain. All the constraints in the proposed methodology have been formulated as sum of squares conditions of which the feasibility is ensured by fully discussed principles. The detailed analysis on numerical and practical examples demonstrates the effectiveness of the proposed method.
Enhanced high dynamic‐range image rendering using a surround map based on edge‐adaptive layer blurring
Authors: Kwon Hyuk‐Ju , Lee Sung‐Hak , Lee Geun‐Young , Sohng Kyu‐Ik
Published: April 2016

Many tone‐mapping methods have developed efficient tone compression and local contrast enhancement techniques for high dynamic‐range imaging. Local tone mapping enhances the image quality to reveal the details; however, it causes artefacts such as halos. Halo artefacts appear around the edges of an image and lead to deterioration in the overall image quality. Detail‐base separation and multi‐scale methods have been developed to reduce halo artefacts. Detail‐base separation methods divide the image into a detail layer and base layer using an edge‐preserving filter and process each layer independently. Multi‐scale methods alleviate artefacts such as halos, noise, and awkward global toning using a weighted sum of single‐scale images. These methods have several inherent problems including the complexity of the edge‐preserving filter and multi‐processing redundancy. Therefore, in this study, a novel surround map is presented to resolve halo artefacts and enhance local details in single‐scale processing.
Low‐torque ripple design of a ferrite‐assisted synchronous reluctance motor
Authors: Barcaro Massimo , Pradella Tomas , Furlan Ivano
Published: April 2016

This study illustrates the design of a low‐torque ripple ferrite‐assisted synchronous reluctance machine. The design strategy initially adopts a simplified analytical model in order to select the optimal values for the flux barrier angles that mainly affects the torque ripple. Then, synchronous reluctance rotor geometries selected on the basis of analytical results are analysed by finite elements (FEs) simulations. The simulated geometries are provided by ferrite permanent magnets (PMs) to enhance machine performance. The optimisation steps are properly coordinated in order to realise the maximum reduction of the torque ripple, taking into account the PM quantity and the flux barrier shape as well as the demagnetisation risk. Two optimal rotor geometries are presented and compared in terms of torque ripple by FEs simulations. Then, the comparison have been extended to other machine characteristics (as high‐frequency saliency and demagnetisation tolerance) to the aim of selecting the more promising one. Available measurements on prototypes are reported to confirm the simulation results and the design approach.
Comparisons of three‐phase and five‐phase permanent magnet assisted synchronous reluctance motors
Authors: Bonthu Sai Sudheer Reddy , Choi Seungdeog , Baek Jeihoon
Published: April 2016

This paper presents the comparison of three‐phase and five‐phase permanent magnet assisted synchronous reluctance motors (PMa‐SynRM) in terms of their design and performance characteristics. With higher fault tolerant capability, efficiency, and reliability, the five‐phase PMa‐SynRM can be a better substitute when compared with the three‐phase PMa‐SynRM in critical applications where safety is top priority. In this study, for a fair comparison, same design procedure using in lumped parameter modelling is followed in developing the three‐phase and five‐phase PMa‐SynRMs. The models are optimised to minimise cost and maximise efficiency. For further detailed comparison of the three‐phase and five‐phase PMa‐SynRMs, two‐dimensional finite element analysis (FEA) is utilised. Performance characteristics such as torque pulsation, back electromotive force, flux linkage, d‐ and q‐axis inductances versus their respective currents, cogging torque, efficiency plot, and torque‐speed characteristics are intensively simulated through FEA. The optimised three‐phase and five‐phase PMa‐SynRMs are fabricated with the same power rating (3 kW) and same volume. Experimental tests are conducted on the prototypes to validate the simulation results.
Optimisation and measurement of eddy current damping in a passive tuned mass damper
Authors: van Beek Tom , Pluk Kevin , Jansen Helm , Lomonova Elena
Published: April 2016

This paper describes the optimisation of the eddy current damping, applied in a passive tuned mass damper (TMD). A semi‐analytical model based on scalar potential formulation is extended for different permanent magnet (PM) topologies. Optimal design parameters are acquired by particle swarm optimisation. A 3‐DoF mechanical model is presented to predict the quality reduction factor of the TMD. Measurements are performed for validating the semi‐analytical model. Furthermore, an experiment is carried out to test a TMD with two optimal PM topologies for sinusoidal excitations.
Complex vector modelling and sequence analysis of the integrated three‐phase rotating transformer for design of a symmetrical structure
Authors: Mohabati Hamid Reza , Moghani Javad Shokrollahi , Boroujeni Samad Taghipour
Published: April 2016

In this paper, a complex vector model is provided for an integrated three‐phase shell‐type rotating transformer. The equivalent magnetic circuit is used to obtain the transformer parameters. Furthermore, using vector representation of the dq transformation, the voltage equations of the rotating transformer in double‐reference synchronous frame are obtained. Thanks to the developed model, the transformer design parameters are selected such that the voltage equations in double‐reference frames are decoupled. For the first time, the machine complex vector representation is exploited to design a symmetrical rotating three‐phase transformer. For this purpose, two separated equivalent circuits in double‐reference frames or two decoupled sequences networks are developed. The decoupled circuits simplify the analysis of the rotating transformer in the unbalanced conditions as well as balanced circuits. Being symmetrical is an important issue for the rotating transformer connected to the rotor winding of a doubly‐fed induction generator. Moreover, the steady‐state performance and sequence analysis of the rotating transformer are discussed. Finally, the validity of the obtained model and accuracy of the presented analysis are verified by finite element analysis and experimental tests.
Sensorless speed estimation in wound rotor induction machines by spectral search of the stator phase power signal
Authors: Tshiloz Kavul , Vilchis‐Rodriguez Damian , Djukanović Slobodan , Sarma Nur , Djurović Siniša
Published: April 2016

This paper investigates the feasibility of utilising the stator phase power signal to establish sensorless speed estimation schemes in wound rotor induction machines (WRIMs). To this end, the authors derive and validate closed form expressions defining the possible power signal spectral content containing rotor speed information. Based on these, two novel sensorless speed estimation techniques are proposed: the first enables supply frequency independent speed estimation in WRIM extended slip applications, while the second facilitates estimation in a wide operating speed range for scalar controlled WRIM applications based on a sliding‐window search of the power spectrum. The proposed techniques are underpinned by a dichotomous search enabled spectral processing algorithm and shown to deliver an increase in attainable real‐time estimation rate without compromising estimation accuracy. The performance of reported schemes is assessed and validated in real‐time laboratory experiments.
Determining demagnetisation risk for two PM wind power generators with different PM material and identical stators
Authors: Sjökvist Stefan , Eklund Petter , Eriksson Sandra
Published: April 2016

Ways to utilise ferrite permanent magnets (PMs), in a better way has been in focus the last couple of years since the use of neodymium‐iron‐boron (NdFeB) PMs has been debated. While ferrite PMs offer a low‐cost alternative to rare‐earth PMs, it is a trade‐off for lower energy density. Depending on the type of PM and if the PMs are surface mounted or buried, the risk of demagnetisation during a fault condition can vary significantly between machines. In this study, the demagnetisation risk of two electrically similar generators with identical stators has been studied during several short‐circuit faults at different temperatures. The study is simulation‐based, and the results show that the generator with the ferrite rotor will suffer from a small but not significant amount of demagnetisation in the worst, three‐phase‐neutral, short‐circuit case at a temperature of 5°C, whereas the NdFeB PMs will suffer from partial demagnetisation if a fault occurs at 120°C. For operational temperatures between 20 and 60°C both generators will sustain a short‐circuit event.
Analysis of a new five‐phase fault‐tolerant doubly salient brushless DC generator
Authors: Liwei Shi , Bo Zhou
Published: April 2016

The fault‐tolerant ability of a multi‐phase doubly salient electromagnetic generator (DSEG) makes it suitable for important applications. However, asymmetric phase windings are a drawback of the traditional five‐phase DSEG. This study presents the design of a new five‐phase brushless DSEG with symmetrical phases and a robust rotor. The proposed stator poles, rotor poles, and their pole arc criteria form a general design basis for the multiphase DSEG with minimum cogging torque. The proposed new winding configuration overcomes the phase asymmetry drawback of the traditional DSEG. An analysis of the characteristic of the no‐load and the loading operation of the five‐phase DSEG shows that the five‐phase DSEG has fewer harmonics than the three‐phase DSEG does. Additionally, the five‐phase DSEG has high fault‐tolerance ability because adjacent phases will take over the activity of the fault phase if there is an open‐circuit fault. Simulated and experimental results of machine performance under the same working conditions offer verification of the design principles presented.
Influence of the antioxidant on the long‐term ageing characteristics of oil–paper insulation and the deposition and migration of copper sulphide in oil‐immersed transformers
Authors: Yang Lijun , Gao Sihang , Li Jinzhong , Sun Weidong
Published: April 2016

This paper investigated the influence of 2, 6‐di‐tert‐butyl‐p‐cresol (DBPC) on the long‐term ageing characteristics of oil–paper insulation and the deposition and migration of copper sulphide induced by the reaction of copper and dibenzyl disulphide (DBDS) in oil‐immersed transformers. A thermal ageing experiment at 130°C were designed and conducted by adding different concentrations of DBPC to the naphthenic mineral oil and after the experiments a set of characteristic parameters were tested. The result indicates that the excessive concentration (≥0.6%) of DBPC will slightly increase the ageing of insulating oil and increase the carboxyl group in the mineral oil, affecting the reaction of DBDS and copper, and the insulating paper wrapped on the copper strip was also aged seriously accordingly. Meanwhile, the deposition of copper sulphide on the insulating paper is found to be slightly increased with the increase of the concentration of DBPC. When insulating oil contains DBPC and DBDS, due to migration of DBDS–Cu and DBPC–Cu in oil, the copper ions in the oil would be fluctuating at a certain period of time. Although the addition of a small concentration of DBPC can improve the antioxygenic property of the insulting oil to some extent, the transformers that contain excessive concentration of DBPC may be more harmful than beneficial.
Method to diagnose open‐circuit faults in active power switches and clamp‐diodes of three‐level neutral‐point clamped inverters
Authors: Abadi Mohsen Bandar , Mendes André Manuel Santos , Cruz Sérgio Manuel Ângelo
Published: April 2016

A new real‐time method able to diagnose multiple semiconductor open‐circuit (OC) faults in a three‐level neutral‐point clamped inverter is introduced in this paper. The proposed diagnostic method is based on the evaluation of the output pole voltages and output currents of the inverter. The proposed method allows a real‐time detection and localisation of multiple OC faults in all active power switches and clamp‐diodes within one modulation period. Experimental results obtained for different operating conditions of the inverter demonstrate the applicability and performance of the proposed diagnostic approach.
Approach for analytical modelling of axial‐flux PM machines
Authors: Taghipour Boroujeni Samad , Abedini Mohammadi Abdolmajid , Oraee Ashknaz , Oraee Hashem
Published: April 2016

In the presented paper, an analytical model is developed for calculation of the air gap magnetic flux density in the axial‐flux surface‐mounted PM machines. The slotting effect is taken into account in the air gap magnetic flux distribution, accurately. The main novelty of this study is replacing the stator teeth by some surface currents at the border of the removed stator teeth. The uniqueness theorem is applied to find the surface currents. The two‐dimensional (2D) field solution in the slotless machine is solved easily by separation of variables method. The multi‐slice quasi‐3D method is applied for taking 3D nature of field distribution into account. In addition, the back‐EMF, armature inductances and electromagnetic and cogging torque are computed based on the predicted air gap flux density. Moreover, for the first time, the Lorentz equation besides Maxwell’ stress tensor is applied for computation of the cogging torque. The validity of the proposed procedure and the obtained results are verified by 3D finite element analysis.
Model‐based loss minimisation scheme for wind solar hybrid generation system using (grid‐connected) doubly fed induction generator
Authors: Parida Adikanda , Chatterjee Debashis
Published: April 2016

A wind–solar hybrid system using doubly fed induction generator (DFIG) is described in this study. An optimum rotor current control strategy considering minimum losses of the induction generator over entire period of operation is proposed. In the proposed scheme, a solar photovoltaic (PV) unit of appropriate capacity has been augmented with the rotor circuit of the DFIG along with a marginal battery backup to supplement the rotor power in order to maintain continuity of power generation. The active power fluctuations at the stator terminals of the DFIG can be minimised as both solar PV and wind energy can complement each other during lean periods of either of the sources. The proposed scheme has been simulated and experimentally validated with a 2.5 kW DFIG using dSPACE CP1104 module, which produced satisfactory results.