bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory investigation of particle acceleration and magnetic field compression in collisionless colliding fast plasma flows
Authors: Higginson D. P. , Korneev Ph. , Ruyer C. , Riquier R. , Moreno Q. , Béard J. , Chen S. N. , Grassi A. , Grech M. , Gremillet L. , Pépin H. , Perez F. , Pikuz S. , Pollock B. , Riconda C. , Shepherd R. , Starodubtsev M. , Tikhonchuk V. , Vinci T. , d’Humières E. , Fuchs J.
Published: June 2019

In many natural phenomena in space (cosmic-rays, fast winds), non-thermal ion populations are produced, with wave-particle interactions in self-induced electromagnetic turbulence being suspected to be mediators. However, the processes by which the electromagnetic energy is bestowed upon the particles is debated, and in some cases requires field compression. Here we show that laboratory experiments using high-power lasers and external strong magnetic field can be used to infer magnetic field compression in the interpenetration of two collisionless, high-velocity (0.01–0.1c) quasi-neutral plasma flows. This is evidenced through observed plasma stagnation at the flows collision point, which Particle-in-Cell (PIC) simulations suggest to be the signature of magnetic field compression into a thin layer, followed by its dislocation into magnetic vortices. Acceleration of protons from the plasma collision is observed as well. As a possible scenario, with 1D and 2D PIC simulations we consider a compression of the vortices against dense plasma remnants.
Coherent transport of quantum states by deep reinforcement learning
Authors: Porotti Riccardo , Tamascelli Dario , Restelli Marcello , Prati Enrico
Published: June 2019

Some problems in physics can be handled only after a suitable ansatz solution has been guessed, proving to be resilient to generalization. The coherent transport of a quantum state by adiabatic passage through an array of semiconductor quantum dots is an excellent example of such a problem, where it is necessary to introduce a so-called counterintuitive control sequence. Instead, the deep reinforcement learning (DRL) technique has proven to be able to solve very complex sequential decision-making problems, despite a lack of prior knowledge. We show that DRL discovers a control sequence that outperforms the counterintuitive control sequence. DRL can even discover novel strategies when realistic disturbances affect an ideal system, such as detuning or when dephasing or losses are added to the master equation. DRL is effective in controlling the dynamics of quantum states and, more generally, whenever an ansatz solution is unknown or insufficient to effectively treat the problem.
Mapping the conceptual space formed by students’ understanding of coordination number of a transition metal complex: an exploratory study
Authors: Sreenivasulu Bellam , Subramaniam R.
Published: June 2019

We report here on an exploratory study done with a sample of university students (N= 140) which sought to explore their understanding of the term ‘coordination number’, a concept encountered in the topic of transition metals chemistry, through a simple open-ended question. The findings show that the conceptual space related to the conceptions students harbour span the interval from non-canonical to canonical limits. That is, the responses from the students include incorrect, partially correct and correct answers. Additionally, instructor commentary, based on teaching experience acquired with a number of cohorts of students, is provided for the range of conceptions encountered, a departure somewhat from the traditional approach, and among the very few, if any, studies, which use such an approach. Those conceptions that are partially correct cannot strictly be labelled as alternative conceptions as it is argued that these can still be used by students to solve problems set in certain contexts on the topic.
Monodisperse molecularly imprinted microsphere cartridges coupled with HPLC for selective analysis of dexamethasone and hydrocortisone in cosmetics by using matrix solid-phase dispersion
Authors: Guo Pengqi , Chen Guoning , Shu Hua , Li Peng , Yu Pei , Chang Chun , Wang Yitao , Fu Qiang
Published: June 2019

Monodisperse molecularly imprinted microspheres were used as the MSPD adsorbents for specific extraction of glucocorticoids in cosmetics.
A pH and reduction dual-sensitive polymeric nanomicelle for tumor microenvironment triggered cellular uptake and controlled intracellular drug release
Authors: Su Zhenwei , Xu Yongmin , Wang Yong , Shi Wanqi , Han Shisong , Shuai Xintao
Published: June 2019

An extracellular pH and intracellular reduction dual-sensitive polymeric nanomicelle was developed for tumor microenvironment triggered selective cellular uptake and controlled cytoplasm drug release.
Self-assembly of stimuli-responsive imine-linked calix[4]arene nanocapsules for targeted camptothecin delivery
Authors: Shetty Dinesh , Skorjanc Tina , Olson Mark Anthony , Trabolsi Ali
Published: June 2019

Here we report template-free synthesis of imine-linked calix[4]arene hollow nanocapsules and their utility in the effective delivery of a poorly soluble cancer drug into tumor cells.
Factors determining the vertical orientation of two-dimensional perovskites
Authors: Arai R. , Yoshizawa-Fujita M. , Takeoka Y. , Rikukawa M.
Published: June 2019

Factors determining the orientation of two-dimensional perovskites were examined.
Reactivity among first and second coordination spheres using a multiprotonated ligand and Cu(ii) in the solid-state
Authors: Li Haitao , Yang Yuxia , Famulari Antonino , Xin Lianxin , Martí-Rujas Javier , Guo Fang
Published: June 2019

The solid-state reactivity among nonporous Cu(ii) second and first sphere adducts has been studied using a multidentate flexible ligand in combination with quantum mechanics.
Partition of optical properties into orbital contributions
Authors: Sitkiewicz Sebastian P. , Rodríguez-Mayorga Mauricio , Luis Josep M. , Matito Eduard
Published: June 2019

A new tool to analyze the response property through the partition of nonlinear optical properties in terms of orbital contributions (PNOC), valuable in the assessment of the electronic structure methods in the NLOPs computations, is presented.
Bifunctional catalysts for the hydroisomerization ofn-alkanes: the effects of metal–acid balance and textural structure
Authors: Wang Wei , Liu Chang-Jun , Wu Wei
Published: June 2019

The summary of recent advances reveals excellent potentials for the preparation of novel bifunctional catalysts with excellent catalytic performances forn-alkane hydroisomerization.
Iron-based nanoparticles embedded in a graphitic layer of carbon architectures as stable heterogeneous Friedel–Crafts acylation catalysts
Authors: Zhang Hao , Song Xiaojing , Hu Dianwen , Zhang Wenxiang , Jia Mingjun
Published: June 2019

Carbon supported iron nanoparticles were prepared by pyrolyzing Fe-MOF material of Fe-diamine-dicarboxylic acid, and showed excellent catalytic activity and stability for the Friedel–Crafts acylation of aromatic compounds with acyl chloride.
Previously unidentified sources of perfluoroalkyl and polyfluoroalkyl substances from building materials and industrial fabrics
Authors: Janousek Raphael M. , Lebertz Stephan , Knepper Thomas P.
Published: June 2019

Investigation of building materials and industrial textiles and identification of hitherto unknown sources of PFASs.
Template-free synthesis of oxygen-containing ultrathin porous carbon quantum dots/g-C3N4 with superior photocatalytic activity for PPCPs remediation
Authors: Wang Fengliang , Wang Yingfei , Wu Yuliang , Wei Dandan , Li Lei , Zhang Qianxin , Liu Haijin , Liu Yang , Lv Wenying , Liu Guoguang
Published: June 2019

We report, for the first time, the fabrication of an oxygen-containing ultrathin porous carbon quantum dots/polymeric carbon nitrogen metal-free composite with a highly enhanced photoresponse.
Effect of polysaccharides from adlay seed on anti-diabetic and gut microbiota
Authors: Chen Li-Chun , Fan Zhong-Yang , Wang Hong-Yu , Wen Dong-Cheng , Zhang Shi-Yu
Published: June 2019

The hypoglycemic effects of PAS in type-2 diabetic mice (T2D) may be associated with the regulation of the intestinal microbiota and its metabolic pathways.
Hydroxysafflor yellow A (HSYA) targets the platelet-activating factor (PAF) receptor and inhibits human bronchial smooth muscle activation induced by PAF
Authors: Guo Xinjing , Zheng Meng , Pan Ruiyan , Zang Baoxia , Gao Jianwei , Ma Hanying , Jin Ming
Published: June 2019

HSYA suppressed the activation of human bronchial smooth muscle cells induced by platelet activating factor (PAF) in vitro by targeting the PAFR.
Tetracyanobutadiene (TCBD) functionalized benzothiadiazole derivatives: effect of donor strength on the [2+2] cycloaddition–retroelectrocyclization reaction
Authors: Rout Yogajivan , Mobin Shaikh M. , Misra Rajneesh
Published: June 2019

A series of unsymmetrical and symmetrical mono/di 1,1,4,4-tetracyanobutadiene (TCBD) substituted benzothiadiazoles (BTDs) 2a–2g was synthesized by [2+2] cycloaddition–retroelectrocyclization reaction.
C60 tetragonal crystal sheet grown from evaporated C60 solution
Authors: Chen Li , Pang Xiujiang , Zhao Jian
Published: June 2019

CHCl3 as a non-aromatic solvent for the selective preparation of the two-dimensional C60 crystal with the lateral sizes in microns.
Monoclinic VO2(D) hollow nanospheres with super-long cycle life for aqueous zinc ion batteries
Authors: Chen Linlin , Yang Zhanhong , Huang Yaoguo
Published: June 2019

Monoclinic VO2(D) hollow nanospheres are demonstrated to have long cyclic endurance stability in 3 M ZnSO4 electrolyte for aqueous zinc ion batteries.
Anomalous lattice vibrations of CVD-grown monolayer MoS2 probed using linear polarized excitation light
Authors: Li Feng , Huang Teng-De , Lan Yann-Wen , Lu Ting-Hua , Shen Tao , Simbulan Kristan Bryan , Qi Junjie
Published: June 2019

Anomalous lattice vibrations are observed in CVD-grown monolayer MoS2 when rotating the sample and using the linear polarization incident light.
Promoting Pt catalysis for CO oxidation via the Mott–Schottky effect
Authors: Wu Peiwen , Wu Zili , Mullins David R. , Yang Shi-Ze , Han Xue , Zhang Yafen , Foo Guo Shiou , Li Huaming , Zhu Wenshuai , Dai Sheng , Zhu Huiyuan
Published: June 2019

“Mott–Schottky modulated catalysis” on Pt nanoparticles was reported to promote Pt catalysis for CO oxidation.
Supramolecular assembly of functional peptide–polymer conjugates
Authors: Otter Ronja , Besenius Pol
Published: June 2019

The following review gives an overview about synthetic peptide–polymer conjugates as macromolecular building blocks and their self-assembly into a variety of supramolecular architectures, from supramolecular polymer chains, to anisotropic 1D arrays, 2D layers, and more complex 3D networks.
The aza-Michael reaction: towards semi-crystalline polymers from renewable itaconic acid and diamines
Authors: Noordzij G. J. , van den Boomen Y. J. G. , Gilbert C. , van Elk D. J. P. , Roy M. , Wilsens C. H. R. M. , Rastogi S.
Published: June 2019

This paper reports, for the first time, semi-crystalline polymers based on bis-pyrrolidone dicarboxylic acids (BPDA) obtained from the aza-Michael reaction between renewable itaconic acid and various diamines.
Benzyne–azide polycycloaddition: a facile route toward functional polybenzotriazoles
Authors: Xin Dehua , Qin Anjun , Tang Ben Zhong
Published: June 2019

An efficient benzyne–azide polycycloaddition is established and functional poly(benzotriazole)s are produced under mild reaction conditions.
High-performance quasi-solid-state asymmetric supercapacitors based on BiMn2O5 nanoparticles and redox-additive electrolytes
Authors: Bhagwan Jai , Ramulu Bhimanaboina , Yu Jae Su
Published: June 2019

The investigation of nanomaterials with improved energy storage performance is essential in the development of high energy density supercapacitors.
Li4Ti5O12 quantum dot decorated carbon frameworks from carbon dots for fast lithium ion storage
Authors: Li Lin , Jia Xinnan , Zhang Yu , Qiu Tianyun , Hong Wanwan , Jiang Yunling , Zou Guoqiang , Hou Hongshuai , Chen Xianchun , Ji Xiaobo
Published: June 2019

Li4Ti5O12 quantum dots anchored on 3D carbon frameworks from carbon dots were designed and exhibited superior electrochemical lithium storage performance.
Synthesis of azuleno[2,1-b]thiophenes by cycloaddition of azulenylalkynes with elemental sulfur and their structural, optical and electrochemical properties
Authors: Shoji Taku , Miura Kota , Ohta Akira , Sekiguchi Ryuta , Ito Shunji , Endo Yuya , Nagahata Tatsuki , Mori Shigeki , Okujima Tetsuo
Published: June 2019

The reaction of several azulenylalkynes having an aryl substituent with elemental sulfur afforded the corresponding azuleno[2,1-b]thiophenes in good yields.
A chiral-at-metal asymmetric catalyzed vinylogous Michael addition of ortho-methyl aromatic nitro compounds for isoxazole derivative synthesis
Authors: Li Shi-Wu , Du Yu , Kang Qiang
Published: June 2019

A chiral-at-metal rhodium(iii) complex catalyzed asymmetric vinylogous Michael addition of 5-methyl 4-nitroisoxazoles with α,β-unsaturated 2-acyl imidazoles has been developed, delivering the corresponding adducts with up to 96% yield and 97% ee.
Structural characterization of Mesobuthus martensii Karsch peptides and anti-inflammatory potency evaluation in human vascular endothelial cells
Authors: Zheng Man , Yan Xiafeng , Bu Fanli , Zhang Fenglei , Li Zhenhua , Cui Jiali , liu Jie , Dong Minya
Published: June 2019

Studies have reported that scorpion toxins have excellent anti-cancer effects; however, the anti-inflammatory activity of scorpion peptides has rarely been studied.
Molecular dynamics simulations of a cyclotetramethylene tetra-nitramine/hydrazine 5,5′-bitetrazole-1,1′-diolate cocrystal
Authors: Zhai Pengfei , Shi Chengying , Zhao Shengxiang , Mei Zongshu , Pan Yinguang
Published: June 2019

An energetic ionic salt-based cocrystal formation, HMX/HA·BTO, is predicted based on molecular dynamics simulations.
Validated liquid chromatography tandem mass spectrometry for simultaneous quantification of foretinib and lapatinib, and application to metabolic stability investigation
Authors: Alanazi Mohammed M. , Alkahtani Hamad M. , Almehizia Abdulrahman A. , Attwa Mohamed W. , Bakheit Ahmed H. , Darwish Hany W.
Published: June 2019

Foretinib metabolic rate is decreased in combination with lapatinib. Lapatinib metabolic rate is greatly increased in combination with foretinib. Dose recalculation should be considered when foretinib and lapatinib are used in combination.
pH-induced conformational changes in histamine in the solid state
Authors: Kodchakorn Kanchanok , Nimmanpipug Piyarat , Phongtamrug Suttinun , Tashiro Kohji
Published: June 2019

The tautomeric and conformational preferences of histamine related to proton transfer were investigated from both theoretical and experimental points of view.
Electrospun silica nanofiber mats functionalized with ceria nanoparticles for water decontamination
Authors: Zucker Ines , Dizge Nadir , Fausey Camrynn L. , Shaulsky Evyatar , Sun Meng , Elimelech Menachem
Published: June 2019

This study demonstrates the fabrication of nanoceria-immobilized silica nanofibers for efficient water decontamination with easy reuse and regeneration properties.
Understanding the piezoelectricity of high-performance potassium sodium niobate ceramics from diffused multi-phase coexistence and domain feature
Authors: Sun Xi-xi , Zhang Junwei , Lv Xiang , Zhang Xi-xiang , Liu Yao , Li Fei , Wu Jiagang
Published: June 2019

Unveiling the physical mechanisms of high performance in potassium sodium niobate-based ceramics from diffused multi-phase coexistence and a single domain feature.
Quad-rotor-shaped non-fullerene electron acceptor materials with potential to enhance the photoelectric performance of organic solar cells
Authors: Yao Chuang , Yang Yezi , Li Lei , Bo Maolin , Peng Cheng , Wang Jinshan
Published: June 2019

We proposed two novel quad-rotor-shaped non-fullerene electron acceptor materials, which exhibit much better optoelectronic properties than that of the widely used non-fullerene acceptor ITIC.
Flame-retardant porous hexagonal boron nitride for safe and effective radioactive iodine capture
Authors: Wang Juan , Ai Kelong , Lu Lehui
Published: June 2019

The porous hexagonal BN with flame retardancy and high stability could serve as the adsorbent for radioactive iodine under harsh spent nuclear fuel reprocessing conditions.
Ultrathin nanosheets of aluminosilicate FER zeolites synthesized in the presence of a sole small organic ammonium
Authors: Xu Hao , Chen Wei , Zhang Guanqun , Wei Pengfei , Wu Qinming , Zhu Longfeng , Meng Xiangju , Li Xiujie , Fei Jinhua , Han Shichao , Zhu Qiuyan , Zheng Anmin , Ma Yanhang , Xiao Feng-Shou
Published: June 2019

Ultrathin nanosheets (6–8 nm) of aluminosilicate FER zeolites have been successfully synthesized using a sole small organic ammonium (N,N-diethyl-cis-2,6-dimethyl piperidinium, DMP).
Significant average ZT enhancement in Cu3SbSe4-based thermoelectric material via softening p–d hybridization
Authors: Zhang Dan , Yang Junyou , Bai Hongchang , Luo Yubo , Wang Bin , Hou Shuaihang , Li Zhiliang , Wang Shufang
Published: June 2019

An effective strategy of the weakening of p–d hybridization is devised to enhance the thermoelectric properties of Cu3SbSe4via Ag substitution.
Phosphonium zwitterions for lighter and chemically-robust MOFs: highly reversible H2S capture and solvent-triggered release
Authors: Reynolds Joseph E. , Bohnsack Alisha M. , Kristek David J. , Gutiérrez-Alejandre Aída , Dunning Samuel G. , Waggoner Nolan W. , Sikma R. Eric , Ibarra Ilich A. , Humphrey Simon M.
Published: June 2019

The tetrahedral zwitterion of tetrakis(p-carboxyphenyl) phosphonium is employed as a unique building block for robust and lighter MOFs that tolerate sorption of acidic gases including H2S.
Bioprinting Schwann cell-laden scaffolds from low-viscosity hydrogel compositions
Authors: Ning Liqun , Zhu Ning , Mohabatpour Fatemeh , Sarker M. D. , Schreyer David J. , Chen Xiongbiao
Published: June 2019

A printable hydrogel composition for Schwann cell-laden tissue scaffold bioprinting in damaged nerve regeneration.
Ultrasound-triggered perfluorocarbon-derived nanobombs for targeted therapies of rheumatoid arthritis
Authors: Zhu Bihui , Wang Liyun , Huang Jianbo , Xiang Xi , Tang Yuanjiao , Cheng Chong , Yan Feng , Ma Lang , Qiu Li
Published: June 2019

The targeted US-triggered PFC-based “nanobombs” with US used to treat the RA in this work would offer a new treatment strategy and have a great potential for the application in the areas of theranostic agent and nanomedicine treatment.
Preventing fungal growth on heritage paper with antifungal and cellulase inhibiting magnesium oxide nanoparticles
Authors: Franco Castillo Isabel , García Guillén Esther , M. de la Fuente Jesús , Silva Filomena , Mitchell Scott G.
Published: June 2019

Magnesium oxide nanoparticles (MgO NPs) as a colourless antifungal treatment with anti-cellulase activity to prevent biodeterioration of paper-based heritage objects.
van der Waals epitaxy for highly tunable all-inorganic transparent flexible ferroelectric luminescent films
Authors: Zheng Ming , Li Xue-Yan , Ni Hao , Li Xiao-Min , Gao Ju
Published: June 2019

The direct fabrication of flexible transparent ferroelectric luminescent films on mica with highly tunable photoluminescence response is demonstrated.
Zero thermal-quenching photoluminescence in fresnoite glass achieved with the assistance of carrier compensating and surface crystal clusters
Authors: Xie Wenqing , Li Panpan , Wang Yun , Zhu Qijing , Zhang Yunjie , Cai Yangjian , Xu Shiqing , Zhang Junjie
Published: June 2019

The glass-ceramic breaks through the high-temperature threshold limitation (over 300 °C) owning to rigid frame-protected energy transfer processes.
Long noncoding RNA: an emerging player in diabetes and diabetic kidney disease
Authors: Guo Jia , Liu Zhangsuo , Gong Rujun
Published: June 2019

Diabetic kidney disease (DKD) is among the most common complications of diabetes mellitus (DM), and remains the leading cause of end-stage renal diseases (ESRDs) in developed countries, with no definitive therapy yet available. It is imperative to decipher the exact mechanisms underlying DKD and identify novel therapeutic targets. Burgeoning evidence indicates that long non-coding RNAs (lncRNAs) are essential for diverse biological processes. However, their roles and the mechanisms of action remain to be defined in disease conditions like diabetes and DKD. The pathogenesis of DKD is twofold, so is the principle of treatments. As the underlying disease, diabetes per se is the root cause of DKD and thus a primary focus of therapy. Meanwhile, aberrant molecular signaling in kidney parenchymal cells and inflammatory cells may directly contribute to DKD. Evidence suggests that a number of lncRNAs are centrally involved in development and progression of DKD either via direct pathogenic roles or as indirect mediators of some nephropathic pathways, like TGF-β1, NF-κB, STAT3 and GSK-3β signaling. Some lncRNAs are thus likely to serve as biomarkers for early diagnosis or prognosis of DKD or as therapeutic targets for slowing progression or even inducing regression of established DKD. Here, we elaborated the latest evidence in support of lncRNAs as a key player in DKD. In an attempt to strengthen our understanding of the pathogenesis of DKD, and to envisage novel therapeutic strategies based on targeting lncRNAs, we also delineated the potential mechanisms of action as well as the efficacy of targeting lncRNA in preclinical models of DKD.
Developments in molecular epidemiology of aging
Authors: Hägg Sara , Belsky Daniel W. , Cohen Alan A.
Published: June 2019

The field of molecular epidemiology of aging involves the application of molecular methods to measure aging processes and their genetic determinants in human cohorts. Over the last decade, the field has undergone rapid progress with a dramatic increase in the number of papers published. The aim of this review is to give an overview of the research field, with a specific focus on new developments, opportunities, and challenges.

Aging occurs at multiple hierarchical levels. There is increasing consensus that aging-related changes at the molecular level cause declines in physiological integrity, functional capacity, and ultimately lifespan. Molecular epidemiology studies seek to quantify this process. Telomere length, composite scores integrating clinical biomarkers, and omics clocks are among the most well-studied metrics in molecular epidemiology studies.

New developments in the field include bigger data and hypothesis-free analysis together with new modes of collaborations in interdisciplinary teams and open access norms around data sharing. Key challenges facing the field are the lack of a gold standard by which to evaluate molecular measures of aging, inconsistency in which metrics of aging are measured and analyzed across studies, and a need for more longitudinal data necessary to observe change over time.
Diagnostic Accuracy of Sentence Recall and Past Tense Measures for Identifying Children's Language Impairments
Authors: Redmond Sean M. , Ash Andrea C. , Christopulos Tyler T. , Pfaff Theresa
Published: June 2019

Purpose

Measures of linguistic processing and grammatical proficiency represent strong candidates for adaptation into language screeners for early elementary students. One key barrier, however, has been the lack of consensus around the preferred reference standard for assigning affected status. Diagnostic accuracies associated with sentence recall and past tense marking index measures were examined relative to 5 different reference standards of language impairment: receipt of language services, clinically significant levels of parental concern, low performance on language measures, a composite requiring at least 2 of these indicators, and a composite requiring convergence across all indicators.

Method

One thousand sixty grade K–3 students participated in school-based language screenings. All students who failed the screenings and a random sampling of those who passed were invited to participate in confirmatory assessments. The community-based sample was supplemented by a clinical sample of 58 students receiving services for language impairment. Two hundred fifty-four students participated in confirmatory testing. Examiners were naive to participants' status.

Results

Diagnostic accuracies for the sentence recall and past tense marking index measures varied across the different reference standards (areas under receiver operating characteristic curves: .67–.95). Higher levels of convergence occurred with reference standards based on behavioral measures. When affected status was defined by receipt of services and/or parental ratings, cases presented with higher levels of performance on the language measures than when affected status was based on behavioral criteria.

Conclusion

These results provide additional support for the adaptation of sentence recall and past tense marking to screen for language impairments in early elementary students.

Supplemental Material

https://doi.org/10.23641/asha.8285786
Efficient beam allocation strategy for statistical beamforming‐based massive multiple‐input–multiple‐output downlink systems
Authors: Jayakumar Roscia Jeya Shiney , Ganesan Indumathi
Published: June 2019

This study focuses on an efficient fairness aware beam allocation strategy which is based on user position approach. The proposed algorithm is efficient to cope with the effects of user position uncertainties and imperfect channel state information (CSI). It allocates beam to individual users based on directivity and user position with the objective of serving many users simultaneously. On the basis of the user position, individual data rate requirements are also considered in the proposed scheme which is very much important for practical systems thereby considering the fairness issue amongst the users. The proposed scheme is best suited for a system with covariance‐based beamforming, where statistical CSI is highly preferred under high dense deployments and the channel coherence time is short. It also requires low average feedback load with less multiuser interference and is of low complexity compared with the searching‐based beam allocation strategy. The simulation results are given to show the advantage of the proposed beam allocation on comparing with the prevailing schemes.
MMSE‐based iterative processing with imperfect channel and parity check in MIMO systems
Authors: Jiang Fan , Li Cheng , Gong Zijun , Zhang Yan , Liu Shudong , Hao Kun
Published: June 2019

It is known that the acquisition of the complete channel state information at receivers is difficult in multiple‐input multiple‐output (MIMO) systems. Channel estimation error is unavoidable in practical applications. Under imperfect channel conditions, the channel estimate is directly applied to the equalisation process in the conventional minimum mean‐square error (MMSE)‐based turbo equalisation scheme. A few studies treat the channel estimation error as an independent component from the channel estimate and slightly enhanced performance is achieved. Unlike the existing work, the authors derive the MMSE‐based iterative processing conditioned on channel estimate. Moreover, they note that in low‐density parity check coded systems, the parity‐check procedure is also involved. The pass in parity check indicates that the message bitstream is successfully recovered. This information can be utilised to reduce the overall computational complexity by degrading the MIMO size since the unknown parameters are reduced. By extending the analysis in a small‐scale MIMO system to a large‐scale one, they propose to utilise the normalised transmission power in the development. Numerical results show the proposed schemes outperform the existing schemes in terms of system bit error rate and computational complexity performance.
Performance analysis of the odd–even uniform interleaver for turbo codes
Authors: Arkoudogiannis Konstantinos S. , Dimakis Christos E.
Published: June 2019

Interleaver design has been an intense research area since the invention of turbo codes, both from theoretical and technological perspectives, still receiving the attention of engineers. This work is a theoretical treatment on the subject of interleaver design, bringing into focus the odd‐even constraint. Odd‐even interleavers constrain information symbols at odd (even) positions to remain at odd (even) positions after interleaving. Having been adopted in a range of operational communication standards as parts of turbo codes on the one hand, and having raised scepticism about their gain in the literature of turbo trellis‐coded modulation on the other hand, these interleavers have motivated the present article. Concretely, the authors perform a bit‐error analysis of turbo‐code ensembles generated by the odd–even uniform interleaver, following the union‐bound approach by Benedetto et al. for the analysis of the uniform interleaver. They find that the odd–even constraint does not affect the interleaver gain of uniform‐interleaver ensembles; rather, it triggers a redistribution of multiplicities that leads to slightly worse performance mainly in the error‐floor region. The authors' findings are corroborated by bit‐error‐rate simulations.
Prolonging smart grid network lifetime through optimising number of sensor nodes and packet length
Authors: Elwekeil Mohamed , Abdalzaher Mohamed S. , Seddik Karim
Published: June 2019

In the era of internet‐of‐things (IoT), many applications utilise wireless sensor networks (WSNs)including smart grids (SGs). Designing WSNs to fulfill the SGs requirementsimposes some challenges such as limited power and signal propagationimpairments, especially, in harsh environments. Consequently, saving powerconsumption in WSNs‐based SGs is among the most significant challenges. Thetotal power required at a certain sensor depends on two main parameters: thepacket length and inter‐node distance. This paper investigates the optimalpacket length and inter‐node distance to be utilised in a SG over six differentenvironments aiming at maximising the network lifetime. The investigation isbased on a link‐layer model using Tmote Sky nodes taking into consideration thesix environments impact. A mixed‐integer programming (MIP) model is utilised todetermine the best packet length and number of nodes for maximising the networklifetime. This model analyses the performance of maximum SG network lifetimeover those environments and addresses the inter‐node distance effect on thenetwork lifetime maximisation. Simulation results show that decreasing thenumber of nodes covering a certain area is preferable to prolonging the networklifetime. Furthermore, for the considered models, the longer the packet lengthis, the longer the network lifetime will be.
Power allocation scheme for downlink and uplink NOMA networks
Authors: Xie Shaoguo
Published: June 2019

Resource allocation problem is a key issue in multi‐carrier non‐orthogonal multiple access (NOMA) networks. Maximum access problem and power allocation problem are two important problems in resource allocation problem. In this study, two algorithms are proposed to solve the two problems for multi‐carrier NOMA networks, namely mixed integer programming algorithm (MIPA) and dynamic power allocation algorithm (DPAA). In order to solve the maximum access problem, a MIPA is proposed in uplink multi‐carrier NOMA networks. For the power allocation problem, a DPAA is proposed in downlink multi‐carrier NOMA networks. Simulation results show that MIPA can increase the number of supported users compared to other schemes, DPAA can improve user data rate by increasing mean channel quality indicator and make power allocation more reasonable. According to DPAA, the gains of weighted sum‐rate utility per subcarrier can be improved with the increase in the number of subcarriers. Simulation results also show that the proposed scheme is superior to reservation channel technique in terms of the probability of call dropping and probability of call blocking.
Performance of relay‐based decode‐and‐forward cooperative diversity systems over Rayleigh fading channels with non‐identical interferers
Authors: Al‐Mistarihi Mamoun F. , Mohaisen Rami , Darabkh Khalid A.
Published: June 2019

Incremental relaying was initially presented so as to adjust for the shortages or limitations related to the usual cooperative methods, specifically, the fixed relaying methods in which the relay node assists the source node in transmitting the signals belonging to the destination independent of the channel status. Matter of fact, the adaptive relaying methods related to the cooperative diversity networks have attracted current researchers’ attention as of being capable of offering an efficient way in assigning the channel expedients when required. In this study, a two‐hop decode‐and‐forward incremental relaying over Rayleigh fading channels is assessed taking into account the existence of multiple non‐identical interferers close to the destination. Interestingly, investigating the non‐identical interferers case instead of identical ones, like what are published in the literature, is extremely challenging as it refers to a more generalised case. Interestingly, the performance of the system is degraded due to co‐channel interference. To this end, tight closed‐form expressions of the bit error rate and outage probability are ultimately obtained. Analytical and simulation results are introduced to consolidate the assumptions considered.
Orthogonal frequency division multiplexing‐based time difference of arrival estimation
Authors: Abudabbousa Ahmad , Abu‐Hudrouss Ammar M. , Benlarbi‐Delaï Aziz
Published: June 2019

This study presents a spectral approach to estimate the time difference of arrival (TDOA) between a reference unit, composed of a pair of very close antennas (small baseline regarding the operating bandwidth), acting as a known fixed location transmitter, and a mobile unit acting as a single antenna receiver. It uses the channel frequency response (CFR) based on an orthogonal frequency division multiplexing multicarrier communications in a multiple‐input‐single‐output antenna configuration. By handling the CFR responses, seen as wideband interferometric signals, the authors minimise a cost function expressed as the difference between measured channel response and a predefined direct model. Effects of noise and multipath are evaluated and mitigated by the averaging process. The overall performances of the system are analysed, and the experimental validation is systematically led. In a small‐scale indoor environment, it has been shown that the TDOA can be accurately estimated with higher accuracy than the conventional techniques. The proposed method allows, for example, estimating TDOAs of about 2 ns when using a null‐to‐null bandwidth of 100 MHz. Such an approach, based on existing communication systems, and suitable for the 5G norm, can be useful for several applications needing accurate positioning, without requiring complex dedicated infrastructure.
Magnetic properties and vibration characteristics of amorphous alloy strip and its combination
Authors: Liu Daosheng , Li Jiachen , Noubissi Romaric Kammeugue , Wang Shihui , Xu Xiangdong , Liu Qianming
Published: June 2019

Although the cores made with amorphous metal alloy have lowered no‐load losses compared with the orientation silicon steel cores, a high cost and noise level are inevitable because the magnetostriction for amorphous metal alloy strip is larger than the ordinary one. This study mainly focused on the experimental systems and methods for magnetic properties measurement, vibration characteristics and noise level of amorphous alloy strip and combinations. The vibration characteristics and noise level of amorphous alloy composite strip were also studied. The influence of the annealing process on magnetic energy, vibration characteristics and noise level of amorphous alloy core were analysed in detail as well. All the testing results and analysis above are helpful for the transformer manufacturers, and they can replace the expensive amorphous alloy metal strip with the combinations to reduce the noise and cost of the cores.
Detection and quantitative diagnosis of axial displacement of transformer winding by frequency response analysis
Authors: Miyazaki Satoru , Tahir Mehran , Tenbohlen Stefan
Published: June 2019

Transfer functions of a transformer whose winding is axially displaced are measured in several connection schemes of frequency response analysis (FRA), and the sensitivities of the measured transfer functions in these connection schemes to the axial displacement are evaluated. For the objective evaluation, some numerical indices are employed, and it is found that the inductive inter‐winding measurement is the most sensitive to the axial displacement. Furthermore, a simple circuit model is proposed to reproduce the measured transfer functions. All the parameters of the proposed circuit model can be determined from the measured transfer functions in FRA. The proposed model can also reproduce the measured transfer functions with the axial displacement by varying one parameter. The variation of the parameter in reproducing the transfer function with the axial displacement show good linear relation to the amount of the axial displacement. This indicates the possibility of a quantitative diagnosis of the axial displacement by FRA.
Three‐phase power flow calculation considering probability and interval uncertainties for power distribution systems
Authors: Wang Chun , Ao Xin , Fu Wenbin
Published: June 2019

Factors such as the stochastic nature of weather condition and arbitrariness of loads make power flow have both probability and interval properties. In order to solve power flow considering probability and interval uncertainties for power distribution systems, an approximate method, which combines affine linear three‐phase power flow and Latin hypercube sampling (LHS) method, is proposed. The formulation of affine node voltage is derived based on affine inverse operation and conservative estimation method. Bound influences of interval variables (BIIVs) of affine node voltage are used to determine the upper bound and lower bound of the result of probabilistic power flow. Further decomposition of BIIVs, which contributes to reduce the conservation of results, is given. The effectiveness of the proposed method is verified using the modified IEEE 13‐bus system and IEEE 123‐bus system by comparing with LHS‐Monte‐Carlo simulation method.
Optimal sizing of an AC‐coupled hybrid power system considering incentive‐based demand response
Authors: Combe Matthew , Mahmoudi Amin , Haque Mohammed H. , Khezri Rahmat
Published: June 2019

This study investigates the impact of incentive‐based demand response on the optimal economic sizing of hybrid power systems for a remote area in South Australia. The hybrid power systems are modelled as AC‐coupled system with various power generation and energy storage systems including diesel generators, solar photovoltaics, wind turbines, battery storages and flywheels. Operating reserve requirements are introduced to ensure a specified reliability with variable renewable energy generation and consumer loads. Incentive‐based demand response is introduced to allow a reduction in customer loads, up to a maximum value, during peak load events. Customers receive a financial benefit as an incentive for the total demand response energy reduction. Active power operation of four different power system configurations is modelled over one year in hourly time steps. The study uses real data for customer demand, wind speed, solar insolation and ambient temperature profiles in a specific location. The hybrid power systems with demand response are optimised to minimise the system net present cost in project lifetime (20 years) using a particle swarm optimisation algorithm. Sensitivity analysis of levellised cost of energy for various values of the maximum demand response power and the incentive payments are also carried out.
Realisation of compact quasi‐elliptic bandpass filters based on coupled eighth‐mode SIW cavities
Authors: Liu Qing , Zhou Dongfang , Lv Dalong , Zhang Dewei , Zhang Yi
Published: June 2019

A novel basic quasi‐elliptic response bandpass filter in quadruplet based on coupled TE101‐mode‐based eighth‐mode substrate integrated waveguide (EMSIW) cavities is proposed and analysed firstly. The negative cross coupling is achieved by the nature of coupled fringe electric‐field components of the first and fourth cavities. Then, based on the proposed basic quadruplet structure, two methods using a step‐impedance resonator and meandered feeding lines, respectively, are introduced and analysed to realise S‐L coupling to improve the upper stopband performance further. Finally, two possible structures with quasi‐inline and quasi‐folded layouts, respectively, are proposed to realise sixth‐order EMSIW filters. Five EMSIW filters are designed, fabricated, and measured to demonstrate and verify the proposed structures. The proposed filters have the advantages of compact size, good out‐of‐band rejection and realisation of higher‐order filtering function. The size of the realised 4th‐/6th‐order filter is less than . The out‐of‐band rejection higher than 28 dB can reach 2.32f0.
General design equations for 3‐way unequal‐split Bagley power dividers
Authors: Jibreel Omar , Dib Nihad , Al Shamaileh Khair
Published: June 2019

In this study, general design equations for 3‐way unequal‐split Bagley power dividers (BPDs) are systematically derived. The proposed design procedure allows for obtaining power dividers with the same split ratio but with different solutions for design parameters. Conditions are firstly derived to achieve a perfect input port matching, then, taken into consideration to divide the power unequally between the output ports. A technique to compensate the resulting impractical high‐impedance transmission lines is presented, where such lines are replaced by their equivalent single‐ and dual‐frequency T‐shaped sections. To validate the derived equations, different dividers with different split ratios, specifically, 1:3:1, 1:10:1, 3:1:3 and 10:1:10 are designed and simulated. Furthermore, 3‐way dual‐band 10:1:10 BPDs are designed, fabricated and tested. Very good agreement between simulated, theoretical and experimental results is found.
Mathematical model for the optimal determination of voltage level and PCC for large wind farms connection to transmission network
Authors: Đorđević Ana , Đurišić Željko
Published: June 2019

This study presents a practical mathematical model for the determination of the optimal point of connection of large wind farms to the transmission network. A comparative analysis of costs of connecting wind farms to the transmission network is given, about their distance from the point of common coupling (PCC). Calculations have been made for different installed capacity of the wind farm and for different voltage levels of PCC. Based on these calculations, there have been defined competitive distances of a wind farm with a certain power from the network of different voltage levels (e.g. 110 and 220 kV) for which the connection costs are equal. Such calculations are widely applicable and can be used by transmission system operators and wind power plant developers to optimise and plan the connection of a wind farm to the transmission network.
Stochastic energy investment in off‐grid renewable energy hub for autonomous building
Authors: Hemmati Reza
Published: June 2019

This study forms and optimises the renewable energy hub to supply load demand in the autonomous building disconnected from electrical grid (i.e. net‐zero energy building). The proposed energy hub is made of hybrid wind‐solar‐hydro generation systems and it is also strengthened by pumped‐storage hydroelectricity and hydrogen storage systems. The hydro system includes two water reservoirs in cascade connection and one pumped‐storage hydroelectricity. The introduced optimisation programming designs proper capacity for cascade water reservoirs and energy storage system as well as optimises their operation. The uncertainties of parameters are included to make the stochastic programming. It is demonstrated that increasing the flow‐in of reservoir 1 by 25% decreases the planning cost by ∼2.5% and decreasing the flow‐in of reservoir 2 by 50% increases the planning cost by ∼16%. When the hydro system does not operate, the wind power must be increased to 10 kW in order to supply the load. When the wind and solar powers are not integrated, the hydro energy must be increased by 50%.
Energy‐efficient routing protocol based on sink mobility for wireless sensor networks
Authors: Rady Asmaa , Shokair Mona , El‐Rabaie E.L.‐Sayed M. , Saad Waleed , Benaya Ahmed
Published: June 2019

Recently, many routing protocols have been implemented to accomplish progress in the energy consumption field for data collecting wireless sensor networks. Owing to the existence of many drawbacks for employing a static sink, this study utilises the idea of moving the sink node to achieve amelioration in energy utilisation and provide longer network lifetime. The idea of the proposed protocol depends on combining the mobile sink improved energy‐efficient power‐efficient gathering in sensor information system‐based routing protocol (MIEEPB) with the direct transmission (DT) protocol to utilise the limited energy of wireless sensors efficiently. As the motorised movement of the sink is operated by petrol or electricity, the data loss through the transition of this sink from its current location to the next location must be diminished by restricting the moving distance. In the proposed protocol, the mobile sink must spend at least a certain amount of time (sojourn time) at each of its sojourn locations to avoid overhead. Extensive analysis was implemented on the proposed protocol (called MIEEPB‐DT) to appraise and compare it with MIEEPB and DT. Simulation results show that the proposed MIEEPB‐DT protocol gives better improvement in energy efficiency and network lifetime than both MIEEPB and DT.
Second‐order cone robust AC–DC DOPF considering correlation of wind power
Authors: Tian Yuan , Wang Keyou , Li Guojie , Luo Jinshan , Wang Ying
Published: June 2019

Due to the increasing penetration, intermittent renewable energy sources (RESs), such as wind power, have added additional uncertainties to AC–DC power system operation. The strong correlation between wind power will bring larger computational errors. It makes generation dispatching incompatible with the current single‐period optimal power flow practice. This study presents an AC–DC affinely adjustable robust dynamic optimal power flow (AARDOPF) model. Ellipsoidal uncertainty set is adopted to well fit the spatial‐temporal correlated wind power. Affine policies are utilised in the re‐dispatch process. To apply AC–DC AARDOPF, the base‐point generation is calculated and determined to match the power with forecasted RES output. And once the uncertainty is revealed, generators reschedule its output through participation factors responding to the uncertain fluctuation of RES output to ensure a feasible solution for all realisations of RES output. Then original non‐linear models are transformed into SOCP models. Finally, GUROBI is used to solve this model. Numerical results are obtained on modified AC–DC IEEE 30‐bus and 118‐bus system to minimise the expected operational cost. Comparing with stochastic dynamic optimal power flow (DOPF), this model is proved to be more practical and effective.