bluuebunny/crossref_metadata_2025 huggingface dataset:
Volume unbalance on the 2016 Amatrice - Norcia (Central Italy) seismic sequence and insights on normal fault earthquake mechanism
Authors: Bignami Christian , Valerio Emanuela , Carminati Eugenio , Doglioni Carlo , Tizzani Pietro , Lanari Riccardo
Published: March 2019

We analyse the Mw 6.5, 2016 Amatrice-Norcia (Central Italy) seismic sequence by means of InSAR, GPS, seismological and geologic data. The >1000 km2 area affected by deformation is involving a volume of about 6000 km3 and the relocated seismicity is widely distributed in the hangingwall of the master fault system and the conjugate antithetic faults. Noteworthy, the coseismically subsided hangingwall volume is about 0.12 km3, whereas the uplifted adjacent volumes uplifted only 0.016 km3. Therefore, the subsided volume was about 7.5 times larger than the uplifted one. The coseismic motion requires equivalent volume at depth absorbing the hangingwall downward movement. This unbalance regularly occurs in normal fault-related earthquakes and can be inferred as a significant contribution to coseismic strain accomodated by a stress-drop driven collapse of precursory dilatancy. The vertical coseismic displacement is in fact larger than the horizontal component, consistent with the vertical orientation of the maximum lithostatic stress tensor.
HNF4α is a novel regulator of intestinal glucose-dependent insulinotropic polypeptide
Authors: Girard Romain , Darsigny Mathieu , Jones Christine , Maloum-Rami Faïza , Gélinas Yves , Carpentier André C. , Laplante Mathieu , Perreault Nathalie , Boudreau François
Published: March 2019

Mutations in the HNF4A gene cause MODY1 and are associated with an increased risk of Type 2 diabetes mellitus. On the other hand, incretins are hormones that potentiate reductions in blood glucose levels. Given the established role of incretin-based therapy to treat diabetes and metabolic disorders, we investigated a possible regulatory link between intestinal epithelial HNF4α and glucose-dependent insulinotropic polypeptide (GIP), an incretin that is specifically produced by gut enteroendocrine cells. Conditional deletion of HNF4α in the whole intestinal epithelium was achieved by crossing Villin-Cre and Hnf4αloxP/loxP C57BL/6 mouse models. GIP expression was measured by qPCR, immunofluorescence and ELISA. Gene transcription was assessed by luciferase and electrophoretic mobility shift assays. Metabolic parameters were analyzed by indirect calorimetry and dual-energy X-ray absorptiometry. HNF4α specific deletion in the intestine led to a reduction in GIP. HNF4α was able to positively control Gip transcriptional activity in collaboration with GATA-4 transcription factor. Glucose homeostasis and glucose-stimulated insulin secretion remained unchanged in HNF4α deficient mice. Changes in GIP production in these mice did not impact nutrition or energy metabolism under normal physiology but led to a reduction of bone area and mineral content, a well described physiological consequence of GIP deficiency. Our findings point to a novel regulatory role between intestinal HNF4α and GIP with possible functional impact on bone density.
Circumpolar permafrost maps and geohazard indices for near-future infrastructure risk assessments
Authors: Karjalainen Olli , Aalto Juha , Luoto Miska , Westermann Sebastian , Romanovsky Vladimir E. , Nelson Frederick E. , Etzelmüller Bernd , Hjort Jan
Published: March 2019

Ongoing climate change is causing fundamental changes in the Arctic, some of which can be hazardous to nature and human activity. In the context of Earth surface systems, warming climate may lead to rising ground temperatures and thaw of permafrost. This Data Descriptor presents circumpolar permafrost maps and geohazard indices depicting zones of varying potential for development of hazards related to near-surface permafrost degradation, such as ground subsidence. Statistical models were used to predict ground temperature and the thickness of the seasonally thawed (active) layer using geospatial data on environmental conditions at 30 arc-second resolution. These predictions, together with data on factors (ground ice content, soil grain size and slope gradient) affecting permafrost stability, were used to formulate geohazard indices. Using climate-forcing scenarios (Representative Concentration Pathways 2.6, 4.5 and 8.5), permafrost extent and hazard potential were projected for the 2041–2060 and 2061–2080 time periods. The resulting data (seven permafrost and 24 geohazard maps) are relevant to near-future infrastructure risk assessments and for targeting localized geohazard analyses.
The Subnational Human Development Database
Authors: Smits Jeroen , Permanyer Iñaki
Published: March 2019

In this paper we describe the Subnational Human Development Database. This database contains for the period 1990–2017 for 1625 regions within 161 countries the national and subnational values of the Subnational Human Development Index (SHDI), for the three dimension indices on the basis of which the SHDI is constructed – education, health and standard of living --, and for the four indicators needed to create the dimension indices -- expected years of schooling, mean years of schooling, life expectancy and gross national income per capita. The subnational values of the four indicators were computed using data from statistical offices and from the Area Database of the Global Data Lab, which contains indicators aggregated from household surveys and census datasets. Values for missing years were estimated by interpolation and extrapolation from real data. By normalizing the population-weighted averages of the indicators to their national levels in the UNDP-HDI database, values of the SHDI and its dimension indices were obtained that at national level equal their official versions of the UNDP.
Simultaneous spectrophotometric determination of peracetic acid and the coexistent hydrogen peroxide using potassium iodide as the indicator
Authors: Xiao Junyang , Wang Mengyun , Pang Zijun , Dai Lin , Lu Jinfeng , Zou Jing
Published: March 2019

Recently, increasing attention has been paid towards using commercial peracetic acid (PAA) solution as an efficient disinfectant or a strong oxidant in water treatment.
Tuning the properties of tris(hydroxypyridinone) ligands: efficient 68Ga chelators for PET imaging
Authors: Imberti Cinzia , Chen Yu-Lin , Foley Calum A. , Ma Michelle T. , Paterson Brett M. , Wang Yifu , Young Jennifer D. , Hider Robert C. , Blower Philip J.
Published: March 2019

The outstanding efficiency of the tris(hydroxypyridonone) ligand THPMe for radiolabelling PET radiotracers with 68Ga is surpassed by THPH.
Crystalline nickel, cobalt, and manganese antimonates as electrocatalysts for the chlorine evolution reaction
Authors: Moreno-Hernandez Ivan A. , Brunschwig Bruce S. , Lewis Nathan S.
Published: March 2019

Crystalline transition-metal antimonates (TMAs) such as NiSb2Ox, CoSb2Ox, and MnSb2Ox are moderately active, stable catalysts for the electrochemical oxidation of chloride to chlorine under conditions relevant to the commercial chlor-alkali process.
Vapor-assisted preparation of Mn/Fe/Co/Zn–Cu bimetallic metal–organic frameworks based on octahedron micron crystals (PCN-6′)
Authors: Yang Jiangfeng , Du Bingjie , Yuan Ning , Jia Xiaoxia , Li Jinping
Published: March 2019

A Cu-based metal–organic framework (PCN-6′) with octahedral crystal morphology was synthesized using a strong acid (HCl) and characterized by SEM, TGA and BET, which showed a larger specific surface area and pore volume than the corresponding counterpart that was prepared using a weak acid (oxalate).
Facile construction & modeling of a highly active thiacalixphenyl[4]arene-protected nano-palladium catalyst for various C–C cross-coupling reactions
Authors: Modi Krunal , Patel Chirag , Panchal Urvi , Liska Alan , Kongor Anita , Jiri Ludvik , Jain V. K.
Published: March 2019

A newly designed and synthesized thiacalixphenyl[4]arene tetraacetohydrazide (TPTAH) has been utilized for the construction of palladium nanoparticles (TPTAH-PdNPs), which are found to be catalytically active for the C–C cross-coupling reactions such as the Suzuki–Miyaura, Heck, and Stille reactions.
Two organic–inorganic hybrid polyoxovanadates as reusable catalysts for Knoevenagel condensation
Authors: Li Chunxia , Zhong Dandan , Huang Xianqiang , Shen Guodong , Li Qiang , Du Jiyuan , Li Qianli , Wang Suna , Li Jikun , Dou Jianmin
Published: March 2019

Two novel polyoxovanadates as heterogeneous catalysts have exhibited excellent catalytic properties in the Knoevenagel condensation, especially compound 1's activity is basically maintained after three cycles.
Carbon dot-sensitized MoS2 nanosheet heterojunctions as highly efficient NIR photothermal agents for complete tumor ablation at an ultralow laser exposure
Authors: Geng Bijiang , Qin Hua , Zheng Fengfeng , Shen Wenwen , Li Ping , Wu Kuan , Wang Xulong , Li Xiaokai , Pan Dengyu , Shen Longxiang
Published: March 2019

The design and rational construction of 0D/2D/0D sandwich heterojunctions for greatly enhanced PTT and PCT performances.
Reversible networks of degradable polyesters containing weak covalent bonds
Authors: Bednarek Melania , Kubisa Przemysław
Published: March 2019

The synthesis of reversible polyester networks based mainly on the Diels–Alder chemistry, alkene [2 + 2] cycloaddition or transesterification reactions and studies of their reversibility and its consequences are reviewed.
Broad spectrum absorption and low-voltage electrochromic operation from indacenodithieno[3,2-b]thiophene-based copolymers
Authors: Bini Kim , Murto Petri , Elmas Sait , Andersson Mats R. , Wang Ergang
Published: March 2019

The design and application of IDTT-based conjugated polymers for red-to-transparent and black-to-transparent electrochromic switching at low voltages are reported.
Polydatin ameliorates pulmonary fibrosis by suppressing inflammation and the epithelial mesenchymal transition via inhibiting the TGF-β/Smad signaling pathway
Authors: Qiu Yue , Pan Xue , Hu Yahui
Published: March 2019

Pulmonary fibrosis is a chronic and progressive lung disease which results in a loss of pulmonary function and eventually respiratory failure.
A novel microstructure inspired from Nepenthes alata and lizard skin and its enhanced uni-directional liquid spreading property
Authors: Sun Wenxi , Tang Longjun , Hong Wen , Zhan Yinjin , Yang Bin , Liu Jingquan
Published: March 2019

Innovative biomimetic microstructure inspired by peristome of Nepenthes and lizard skin can achieve liquid uphill spreading.
ZnO/Ag/Ag2WO4 photo-electrodes with plasmonic behavior for enhanced photoelectrochemical water oxidation
Authors: Adam Rania E. , Pirhashemi Mahsa , Elhag Sami , Liu Xianjie , Habibi-Yangjeh Aziz , Willander Magnus , Nur Omer
Published: March 2019

Ag-based compounds are excellent co-catalyst that can enhance harvesting visible light and increase photo-generated charge carrier separation owing to its surface plasmon resonance (SPR) effect in photoelectrochemical (PEC) applications.
Synergetic effect of Na-doping and carbon coating on the electrochemical performances of Li3−xNaxV2(PO4)3/C as cathode for lithium-ion batteries
Authors: Yan Xuedong , Xin Liqing , Wang Hang , Cao Changhe , Sun Shanshan
Published: March 2019

Carbon coated Li3−xNaxV2(PO4)3/C (x = 0.04, 0.06, 0.10, 0.12, 0.18) cathode materials for lithium-ion batteries were synthesized via a simple carbothermal reduction reaction route using methyl orange as the reducing agent.
Pore-tuning to boost the electrocatalytic activity of polymeric micelle-templated mesoporous Pd nanoparticles
Authors: Li Cuiling , Iqbal Muhammad , Jiang Bo , Wang Zhongli , Kim Jeonghun , Nanjundan Ashok Kumar , Whitten Andrew E. , Wood Kathleen , Yamauchi Yusuke
Published: March 2019

Understanding how mesoporous noble metal architectures affect electrocatalytic performance is very important for the rational design and preparation of high-performance electrocatalysts.
Effect of microchannel structure and fluid properties on non-inertial particle migration
Authors: Maitri R. V. , De S. , Koesen S. P. , Wyss H. M. , van der Schaaf J. , Kuipers J. A. M. , Padding J. T. , Peters E. A. J. F.
Published: March 2019

In this work, we investigate the influence of channel structure and fluid rheology on non-inertial migration of non-Brownian polystyrene beads.
Metal–organic framework composites and their electrochemical applications
Authors: Xue Yuqi , Zheng Shasha , Xue Huaiguo , Pang Huan
Published: March 2019

Metal–organic framework composites and their electrochemical applications are introduced to help integrate the advantageous properties and mitigate the disadvantages of their individual components. The synthesis and electrochemical applications of MOF composites are comprehensively summarized, and their outlook in this research area is presented in this review.
One-dimensional copper-based heterostructures toward photo-driven reduction of CO2to sustainable fuels and feedstocks
Authors: Li Jing-Yu , Yuan Lan , Li Shao-Hai , Tang Zi-Rong , Xu Yi-Jun
Published: March 2019

The current rapid industrial development causes both a heavy reliance on non-renewable energy and a dramatic increase in atmospheric CO2concentration, which in turn lead to severe energy and environmental crises.
Vessel graft fabricated by the on-site differentiation of human mesenchymal stem cells towards vascular cells on vascular extracellular matrix scaffold under mechanical stimulation in a rotary bioreactor
Authors: Li Na , Rickel Alex P. , Sanyour Hanna J. , Hong Zhongkui
Published: March 2019

Stem cell differentiation on a decellularized native blood vessel scaffold under mechanical stimulation for vascular tissue engineering.
Substantial thermal conductivity reduction in mischmetal skutterudites MmxCo4Sb12 prepared under high-pressure conditions, due to uneven distribution of the rare-earth elements
Authors: Gainza J. , Serrano-Sánchez F. , Prado-Gonjal J. , Nemes N. M. , Biskup N. , Dura O. J. , Martínez J. L. , Fauth F. , Alonso J. A.
Published: March 2019

Low-cost n-type Mischmetal-filled CoSb3 skutterudites with elemental filling-fraction separation, prepared at high pressure, exhibit markedly low lattice thermal conductivity.
One-step synthesis of wire-in-plate nanostructured materials made of CoFe-LDH nanoplates coupled with Co(OH)2 nanowires grown on a Ni foam for a high-efficiency oxygen evolution reaction
Authors: Zhou Lingxi , Guo Meichen , Li Yao , Gu Qin , Zhang Wenqian , Li Chun , Xie Fengyu , Lin Dunmin , Zheng Qiaoji
Published: March 2019

A series of wire-in-plate nanostructured electrocatalysts for OER with high catalytic activity were fabricated.
MOF-templated self-polymerization ofp-phenylenediamine to a polymer with a hollow box-assembled spherical structure
Authors: Zhou Chunli , Li Ang , Wang Dengke , Pan Erzhuang , Chen Xiaohong , Jia Mengqiu , Song Huaihe
Published: March 2019

Cu–pPD acts as both a structural template and reactant to realize direct conversion from MOFs to polymers in one step.
Homogeneous silver colloidal substrates optimal for metal-enhanced fluorescence
Authors: Lee Daedu , Lee Jaebeom , Song Junghyun , Jen Myungsam , Pang Yoonsoo
Published: March 2019

Particle-size-dependent fluorescence enhancements and dynamics on homogeneous silver nanosurfaces show a strong dependence on the spectral properties of surface plasmons.
Bilayer phosphorene under high pressure: in situ Raman spectroscopy
Authors: Akhtar Meysam , Zhang Congyan , Rajapakse Manthila , Musa Md Rajib Khan , Yu Ming , Sumanasekera Gamini , Jasinski Jacek B.
Published: March 2019

The pressure coefficients in bilayer phosphorene are much different than those in bulk black phosphorus due to substantially reduced interlayer interactions.
Development of a potential energy surface for the O3–Ar system: rovibrational states of the complex
Authors: Sur Sangeeta , Quintas-Sánchez Ernesto , Ndengué Steve A. , Dawes Richard
Published: March 2019

Collisional stabilization is an important step in the process of atmospheric formation of ozone.
[Pb{Mn(CO)5}3][AlCl4]: a lead-manganese carbonyl with AlCl4-linked PbMn3 clusters
Authors: Wolf Silke , Fenske Dieter , Klopper Wim , Feldmann Claus
Published: March 2019

A trigonal planar Pb(+I)Mn3 cluster is observed in the carbonyl compound [Pb{Mn(CO)5}3][AlCl4] that was prepared by ionic-liquid-based synthesis.
Non-uniform electron conduction in weakly ordered SrFe1−xMoxO3−δ
Authors: Merkulov Oleg V. , Markov Alexey A. , Naumovich Eugene N. , Shalaeva Elizaveta V. , Leonidov Ilia A. , Patrakeev Mikhail V.
Published: March 2019

An accelerative increase of the effective electron mobility with Mo content in SrFe1−xMoxO3−δ is due to progressive formation of the Sr2FeMoO6 ordered areas with high electron mobility.
Slow relaxation of magnetization in a {Fe6Dy} complex deriving from a family of highly symmetric metallacryptands
Authors: Athanasopoulou Angeliki A. , Carrella Luca M. , Rentschler Eva
Published: March 2019

A novel family of combined 9-MC-3/12-MC-4 {Fe6Ln} metallacrown-like complexes or else a new form of metallacryptates is reported, while the {Fe6Dy} analogue shows SMM behavior.
Oxidation reactions of a nucleophilic palladium carbene: mono and bi-radical carbenes
Authors: Cui Peng , Hoffbauer Melissa R. , Vyushkova Mariya , Iluc Vlad M.
Published: March 2019

A series of mono and bi-radical carbenes.
Medium-temperature thermoelectric GeTe: vacancy suppression and band structure engineering leading to high performance
Authors: Dong Jinfeng , Sun Fu-Hua , Tang Huaichao , Pei Jun , Zhuang Hua-Lu , Hu Hai-Hua , Zhang Bo-Ping , Pan Yu , Li Jing-Feng
Published: March 2019

Achieving high electronic mobility and excellent thermoelectric performance in GeTe through Ge vacancy suppression and band structure engineering.
Multifunctional carbon dots as a therapeutic nanoagent for modulating Cu(ii)-mediated β-amyloid aggregation
Authors: Chung You Jung , Lee Byung Il , Park Chan Beum
Published: March 2019

Multifunctional carbon dots are synthesized to chelate Cu(ii) ions, suppress Alzheimer's β-amyloid (Aβ) aggregation, and photooxygenate Aβ peptides.
Photoassisted and multiphoton emission from single-crystal diamond needles
Authors: Borz M. , Mammez M. H. , Blum I. , Houard J. , Da Costa G. , Delaroche F. , Idlahcen S. , Haboucha A. , Hideur A. , Kleshch V. I. , Obraztsov A. N. , Vella A.
Published: March 2019

We report on photoassisted and multiphoton electron emission from single-crystal diamond needles and we explore their emission properties.
A far-red to NIR emitting ultra-sensitive probe for the detection of endogenous HOCl in zebrafish and the RAW 264.7 cell line
Authors: Natarajan Vijay , Thirumalaivasan Natesan , Wu Shu-Pao , Sivan Velmathi
Published: March 2019

We report the synthesis of a far-red to NIR emitting probe for its application to the endogenous fluorescence imaging of HOCl in zebrafish.
A palladium-catalyzed multi-component annulation approach towards the synthesis of phenanthrenes
Authors: Song Juan , Wang Songjiang , Sun Haisen , Fan Yuxuan , Xiao Kang , Qian Yan
Published: March 2019

An efficient palladium-catalyzed three-component cascade reaction has been developed for the facile construction of phenanthrene frameworks.
A chemo- and regioselective C6-functionalization of 2,3-disubstituted indoles: highly efficient synthesis of diarylindol-6-ylmethanes
Authors: Wu Qiong , Li Gui-Lin , Yang Shuang , Shi Xiao-Qin , Huang Tian-Zi , Du Xi-Hua , Chen Yan
Published: March 2019

An organocatalytic chemo- and regioselective C6-functionalization of 2,3-disubstituted indoles has been established via a reaction with ortho-hydroxybenzyl alcohols, which afforded biologically important diarylindol-6-ylmethanes in high yields.
Acid/base- and base/acid-switchable complexation between anionic-/cationic-pillar[6]arenes and a viologen ditosylate salt
Authors: Duan Qunpeng , Zhang Hongsong , Mai Wenpeng , Wang Fei , Lu Kui
Published: March 2019

Acid/base and base/acid-controllable molecular switches were constructed based on water-soluble anionic pillar[6]arene or cationic pillar[6]arene and a viologen ditosylate salt.
Asymmetric total synthesis of cryptoconcatone I
Authors: Acharyya Ranjan Kumar , Pal Pratik , Chatterjee Shrestha , Nanda Samik
Published: March 2019

An efficient asymmetric total synthesis of naturally occurring γ-Z-butenolide cryptoconcatone I was achieved by employing substrate-directed reductive epoxide ring opening and late-stage “Pd–Cu” catalyzed cascade cyclization.
On the reactivity of anodically generated trifluoromethyl radicals toward aryl alkynes in organic/aqueous media
Authors: Jud Wolfgang , Kappe C. Oliver , Cantillo David
Published: March 2019

Two competing pathways have been experimentally observed and the selectivity has been explained by means of DFT calculations.
Organo-selenium mediated regio- and stereoselective iodoselenylation of alkynes in an aqueous medium: simple access to (E)-β-iodoalkenyl selenides
Authors: Zeng Xianghua , Chen Lu
Published: March 2019

A method for the simple, efficient, and atom economical iodoselenylation of simple alkynes under mild conditions using molecular iodine (I2) and 1,2-diselanes as starting materials was developed.
Self-molten-polymerization synthesis of highly defected Mn/Sm binary oxides with mesoporous structures for efficient removal of toluene and chlorobenzene
Authors: Liu Lizhong , Zhang Hongbo , Guo Mingming , Zhou Pin , Min Xin , Jia Jinping , Sun Tonghua
Published: March 2019

Oxygen vacancies were induced via transition metal doping in MnOx for the low-temperature and efficient removal of toluene and chlorobenzene.
Structural and computational characterization of a bridging zwitterionic-amidoxime uranyl complex
Authors: Decato Daniel A. , Berryman Orion B.
Published: March 2019

A bridging (μ2) neutral zwitterionic amidoxime binding mode previously unobserved between amidoximes and uranyl is reported and compared to other uranyl amidoxime complexes.
A lysosome-targetable fluorescent probe for the simultaneous sensing of Cys/Hcy and GSH from different emission channels
Authors: Zhang Hui , Xu Lizhen , Li Wenxiu , Chen Wenqiang , Xiao Qi , Huang Jun , Huang Chusheng , Sheng Jiarong , Song Xiangzhi
Published: March 2019

A novel lysosome targetable fluorescent probe, Lyso-AC, that can selectively sense lysosome Cys/Hcy and GSH from different emission channels was developed.
Effects of hydrogen peroxide co-precipitation and inert N2 atmosphere calcination on CeZrLaNd mixed oxides and the catalytic performance used on Pd supported three-way catalysts
Authors: Cui Meisheng , Hou Yongke , Zhai Zhizhe , Zhong Qiang , Zhang Yongqi , Huang Xiaowei
Published: March 2019

Hydrogen peroxide oxidation improves the grains growth. Inert N2 atmosphere calcination reduces the particle size and enlarges the pore channels.
Kinetic study of TBD catalyzed δ-valerolactone polymerization using a gas-driven droplet flow reactor
Authors: Lu Shiyao , Wang Kai
Published: March 2019

The reaction kinetics of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) catalyzed δ-valerolactone polymerization was determined using a gas-driven droplet reactor.
Ultrathin 2D metal–organic framework (nanosheets and nanofilms)-basedxD–2D hybrid nanostructures as biomimetic enzymes and supercapacitors
Authors: Bai Wushuang , Li Sijia , Ma Junping , Cao Wei , Zheng Jianbin
Published: March 2019

xD–2D hybrid nanostructures based on ultrathin 2D TCPP MOF exhibit great potential for application in biomimetic catalase and supercapacitors.
Spatial separation of lithiophilic surface and superior conductivity for advanced Li metal anode: the case of acetylene black and N-doped carbon spheres
Authors: Liang Feng , Lin Liangdong , Feng Zhenyu , Chu Chenxiao , Pan Jun , Yang Jian , Qian Yitai
Published: March 2019

This separation of lithiophilicity and electron conductivity brings significant advantages for electrochemical performances, thereby demonstrating the synergistic effect between them.
Superhydrophilic Cu(OH)2 nanowire-based QCM transducer with self-healing ability for humidity detection
Authors: Lin Jianbin , Gao Naibo , Liu Jiamin , Hu Zhixiang , Fang Han , Tan Xianhua , Li Huayao , Jiang Hao , Liu Huan , Shi Tielin , Liao Guanglan
Published: March 2019

The accurate and reliable measurement of humidity is of great importance in various applications.
An intelligent light-driven thermoelectric conversion system through the thermosensitive phase transition of vanadium dioxide
Authors: Zhang Yuang , Umair Malik Muhammad , Jin Xin , Lu Rongwen , Zhang Shufen , Tang Bingtao
Published: March 2019

A new intelligent light-driven thermoelectric conversion system was designed, which contained PS/Fe2O3-GNS, VO2 film and a thermoelectric module. This system can realize light-thermal-electric conversion and obtain a stable current under sunlight.
Pilot contamination reduction in TDD‐based massive MIMO systems
Authors: Zhao Junhui , Ni Shanjin , Gong Yi , Zhang Qingmiao
Published: March 2019

Channel estimation in time division duplexing (TDD)‐based massive multiple‐input multiple‐output (MIMO) systems is heavily hampered by the pilot contamination, which constitutes a major bottleneck on the overall system performance. This study considers the pilot contamination problem in multi‐cell TDD‐based massive MIMO systems, and analytical expressions are presented on the normalised mean square error (NMSE) of the minimum mean square error channel estimation algorithm. Based on the obtained NMSE, this study proposes an optimal pilot assignment strategy to minimise the effect of pilot contamination. In order to further improve the system performance, a pilot design‐based channel estimation scheme is proposed, where Chu sequences with perfect auto‐correlation property are employed to design the optimal pilot sequences aiming at acquiring the accurate channel state information. Simulation results show that the proposed pilot assignment strategy outperforms the random pilot assignment method, and approaches to the performance of the exhaustive search method which requires high computational complexity. Moreover, the performance gain of the pilot design‐based channel estimation scheme is verified in massive MIMO systems.
Synchronous vibration control for a class of cross‐coupled antisymmetric MSR systems
Authors: Peng Cong , Zhu Mengting , Ren Xiaojun , Zhen Ziyang
Published: March 2019

A magnetically suspended rotor (MSR) system always suffers from the non‐coincidence of the inertia axis and geometric axis, which results in synchronous vibration varied with the rotational speed. To effectively suppress the synchronous vibration torques for the MSR with significant gyroscopic effects, a consolidated vibration control and stability analysis method is proposed here. The MSR system with inherent gyroscopic effects belongs to a class of cross‐coupled antisymmetric system. First, a class of cross‐coupled antisymmetric system with synchronous vibration influence is modelled. Then, the principle and implementation of the proposed scheme used for synchronous vibration suppression are analysed in detail. Moreover, a stability analysis method for a class of cross‐coupled antisymmetric system is developed, which is not limited to the specific MSR system with gyroscopic effects. Finally, the simulation and experiments are performed in the typical magnetically suspended flywheel to demonstrate the effectiveness of the proposed stability analysis method and the vibration suppression algorithm.
Fast generative adversarial networks model for masked image restoration
Authors: Cao Zhiyi , Niu Shaozhang , Zhang Jiwei , Wang Xinyi
Published: March 2019

The conventional masked image restoration algorithms all utilise the correlation between the masked region and its neighbouring pixels, which does not work well for the larger masked image. The latest research utilises Generative Adversarial Networks (GANs) model to generate a better result for the larger masked image but does not work well for the complex masked region. To get a better result for the complex masked region, the authors propose a novel fast GANs model for masked image restoration. The method used in authors’ research is based on GANs model and fast marching method (FMM). The authors trained an FMMGAN model which consists of a neighbouring network, a generator network, a discriminator network, and two parsing networks. A large number of experimental results on two open datasets show that the proposed model performs well for masked image restoration.
Interval data‐based k ‐means clustering method for traffic state identification at urban intersections
Authors: Rao Wenming , Xia Jingxin , Lyu Weitao , Lu Zhenbo
Published: March 2019

Identifying traffic states at urban intersections plays a significant role in achieving the full potential of intelligent transportation systems for various traffic applications (e.g. real‐time traffic signal control). Many traffic state identification methods use mean values of measured or estimated traffic flow variables to identify traffic states; however, lacking a consideration of traffic flow uncertainty leads to inaccurate identifications. To investigate the impact of traffic flow uncertainty on intersection traffic states, this article proposes an interval data‐based k ‐means clustering method for traffic state identification at urban intersections. The uncertainty of three traffic flow variables (volume to capacity ratio, queue length, and delay) are represented in the form of interval data and employed as input variables. The proposed method was implemented on a real‐world traffic network in Kunshan, China. Test results show that the clustering results are explicable and can accurately describe the trend of traffic state evolution. Further investigation shows that the proposed method outperforms the mean‐value‐based method, and queue length has a more significant contribution to the clustering results after the use of interval data. The findings of this study demonstrate the effectiveness of the proposed method in traffic states identification at urban intersections.
Compact broadband frequency selective microstrip antenna and its application to indoor positioning systems for wireless networks
Authors: Bakr Mustafa S. , Großwindhager Bernhard , Rath Michael , Kulmer Josef , Hunter Ian C. , Abd‐Alhameed Raed A. , Witrisal Klaus , Boano Carlo Alberto , Römer Kay , Bösch Wolfgang
Published: March 2019

This study presents a low‐profile broadband microstrip patch antenna with filtering response. The proposed antenna consists of a rectangular patch and four parasitic gap‐coupled elements, two L‐ and two rectangular‐shaped patches. A broadband quasi‐elliptic boresight gain response is obtained without using any extra filtering circuits. The input impedance of each radiating element, i.e., driven patch and parasitic elements, is matched to its radiating quality factor and the couplings between patches are optimised for broadband impedance bandwidth with filtering response. Prototype hardware is designed and fabricated on Kappa 438 substrate with a relative permittivity of 4.4 and thickness of 3.2 mm. The antenna exhibits a total size of 25 × 23 × 3.2 mm3 with relative impedance bandwidth (voltage standing wave ratio<2) of 60% ranging from 4.4 to 7.8 GHz. The experimental results demonstrate good performance with nearly flat gain and good filtering response. The proposed filtering antenna exhibits low pulse distortion in time domain which makes it a good candidate for location‐aware Internet‐of‐things applications employing the IEEE 802.15.4 ultra‐wideband standard. Switchable sector base‐station antenna system is studied to demonstrate the capability of this design to enhance the localisation and communication performance of the wireless network.
Design rule development for frequency‐coded chipless radiofrequency identification with high capacity
Authors: Chen Yen‐Sheng , Jiang Tong‐Yang , Lai Fei‐Peng
Published: March 2019

Recently, considerable attention has arisen over the frequency‐coded chipless radiofrequency identification (RFID), but there is no general consensus on the system specification scheme including encoding techniques, resonators with narrowband and harmonic‐rejected features, and a frequency spectrum used. The purpose of this study is to develop the design rules that improve the capacity and reliability of the chipless RFID. The proposed system development is cast into three phases. Phase one is to determine the encoding scheme that enhances robustness. The limitation of the conventional one‐bit‐per‐resonator approach is identified, and frequency shift encoding is designed to be the kernel of the chipless RFID. Phase two is to determine the resolution of the frequency spectrum by analysing the radar cross‐section for 37 resonators. Four resonators exhibit the narrowband and harmonic‐rejected features, and thus they are recommended to be implemented in the chipless tag. Phase three is to determine the specification on the frequency spectrum. For a 21‐bit example system, the frequency spectrum that meets the trade‐off between the broadband complexity and the size of the tag is 2.0–5.0 GHz. The proposed design rules are validated by conducting simulation and measurement.
Connecting substellar and stellar formation: the role of the host star’s metallicity
Authors: Maldonado J. , Villaver E. , Eiroa C. , Micela G.
Published: March 2019

Context.Most of our current understanding of the planet formation mechanism is based on the planet metallicity correlation derived mostly from solar-type stars harbouring gas-giant planets.

Aims.To achieve a more extensive grasp on the substellar formation process, we aim to analyse in terms of their metallicity a diverse sample of stars (in terms of mass and spectral type) covering the whole range of possible outcomes of the planet formation process (from planetesimals to brown dwarfs and low-mass binaries).

Methods.Our methodology is based on the use of high-precision stellar parameters derived by our own group in previous works from high-resolution spectra by using the iron ionisation and equilibrium conditions. All values were derived in an homogeneous way, except for the M dwarfs where a methodology based on the use of pseudo equivalent widths of spectral features was used.

Results.Our results show that as the mass of the substellar companion increases the metallicity of the host star tends to lower values. The same trend is maintained when analysing stars with low-mass stellar companions and a tendency towards a wide range of host star’s metallicity is found for systems with low-mass planets. We also confirm that more massive planets tend to orbit around more massive stars.

Conclusions.The core-accretion formation mechanism for planet formation achieves its maximum efficiency for planets with masses in the range 0.2–2MJup. Substellar objects with higher masses have higher probabilities of being formed as stars. Low-mass planets and planetesimals might be formed by core-accretion even around low-metallicity stars.
Stellar masses from granulation and oscillations of 23 bright red giants observed by BRITE-Constellation
Authors: Kallinger T. , Beck P. G. , Hekker S. , Huber D. , Kuschnig R. , Rockenbauer M. , Winter P. M. , Weiss W. W. , Handler G. , Moffat A. F. J. , Pigulski A. , Popowicz A. , Wade G. A. , Zwintz K.
Published: March 2019

Context. The study of stellar structure and evolution depends crucially on accurate stellar parameters. The photometry from space telescopes has provided superb data that enabled the asteroseismic characterisation of thousands of stars. However, typical targets of space telescopes are rather faint and complementary measurements are difficult to obtain. On the other hand, the brightest, otherwise well-studied stars, are lacking seismic characterization.

Aims. Our goal is to use the granulation and/or oscillation timescales measured from photometric time series of bright red giants (1.6 ≤ V mag ≤ 5.3) observed with BRITE-Constellation to determine stellar surface gravities and masses.

Methods. We used probabilistic methods to characterise the granulation and/or oscillation signal in the power density spectra and the autocorrelation function of the BRITE-Constellation time series.

Results. We detect a clear granulation and/or oscillation signal in 23 red giant stars and extract the corresponding timescales from the power density spectra as well as the autocorrelation function of the BRITE-Constellation time series. To account for the recently discovered non-linearity of the classical seismic scaling relations, we used parameters from a large sample of Kepler stars to re-calibrate the scalings of the high- and low-frequency components of the granulation signal. We developed a method to identify which component is measured if only one granulation component is statistically significant in the data. We then used the new scalings to determine the surface gravity of our sample stars, finding them to be consistent with those determined from the autocorrelation signal of the time series. We further used radius estimates from the literature to determine the stellar masses of our sample stars from the measured surface gravities. We also defined a statistical measure for the evolutionary stage of the stars.

Conclusions. Our sample of stars covers low-mass stars on the lower giant branch to evolved massive supergiants and even though we cannot verify our mass estimates with independent measurements from the literature, they appear to be at least good enough to separate high-mass from low-mass stars. Given the large known but usually not considered systematic uncertainties in the previous model-based mass estimates, we prefer our model-independent measurements.
CYFFD Parameterization Method for Cylindrical Components of Aircrafts
Authors: He Xiaolong , Bai Junqiang , Li Li , Yang Tihao , Zhang Yu
Published: March 2019

This paper proposes a parameterization method using cylindrical coordinates based free-form deformation(CYFFD) technique by introducing a coordinate transformation method and a virtual lattice method. The method is suitable for axisymmetric and non-axisymmetric cylindrical applications. CYFFD is able to deform radially and circumferentially and to maintain first order and curvature continuity across frame border. First, the coordinate transformation step helps capture geometrical characteristics of cylindrical objects to conduct radial and circumferential deformation. Due to the need of delicate shape design, FFD lattice need be set up closely around cylinder-like objects and this will cause the boundary of FFD frame to intersect with the objects, which lead to derivative discontinuity at the intersection. The virtual lattice method is introduced to reuse some control points as virtual ones so that first order and curvature continuity can be preserved. A cylinder deformation example compares the capability of CYFFD with that of conventional FFD for radial and circumferential deformation and keeping derivative continuity. An airplane nose example shows the possibility to use CYFFD and NFFD together for complex shape. A nacelle deformation example and fitting example show that CYFFD is valuable for non-axisymmetric cylindrical objects with complex shapes. The optimization example on cylinder nose shape indicates that CYFFD can give good optimization results and it is valuable for parameterizing cylinder-like objects.
Numerical Simulation and Characteristic Analysis of Ship's Air Flow Field
Authors: Guo Jiahao , Zhu Xiaoping , Zhou Zhou , Xu Xiaoping
Published: March 2019

The air flow field of ship was simulated by using computational fluid dynamics technology to analyze its prime characteristics with reasonable accuracy. The different results of Reynolds-Averaged Navier-Stokes (RANS) method and Detached Eddy Simulation (DES) were compared, and the calculation traits of these methods were discussed. The results show that the air flow field of ship is unsteady. The accuracy of RANS simulation is insufficient for capturing this unsteady phenomenon. However, DES can catch this with better accuracy and expresses a comparatively great conformity with experimental data. Then, the aircraft carrier's flow field was calculated by DES. The characteristics of vortexes and velocity fluctuation on the ideal landing track were discussed in different wind directions. Those simulations indicate that there are complicated vortexes produced by blunt edges of the island and deck in the flow field. Those vortexes interact and mainly exist in the rear of flight deck and its adjacent air wake. Moreover, they cause a conspicuous and periodical velocity fluctuation on the ideal landing track as time goes on.
Research on Configuration Optimization of Civil Aircraft Spare Parts with Lateral Transshipments and Maintenance Ratio
Authors: Feng Yunwen , Liu Yuchang , Xue Xiaofeng , Lu Cheng
Published: March 2019

A research method for multi-echelon inventory allocation of civil aircraft spare parts with lateral transshipments and maintenance ratio is proposed in this paper, and the maintenance rate is considered into the inventory model, aiming at the problem of multi-echelon inventory allocation with lateral transshipments for civil aircraft spare parts. Firstly, the principle of the multi-echelon inventory model with lateral transshipments and maintenance ratio is proposed. Then, by considering the fleet availability and the satisfaction ratio as the constraints, a mathematical model is built with the inventory system total cost as the optimization objective. Secondly, the procedure of solving multi-echelon inventory allocation model considering the influence of lateral transshipments and maintenance ratio is discussed based on the marginal analysis method. Finally, some components of Boeing 737 are selected as the research objects, the multi-echelon inventory allocation is investigated by considering lateral transshipments and maintenance ratio. The analysis results in this paper show the best number of multi echelon inventory allocation, the minimum inventory system total cost and the fleet availability are 1.205 million dollars and 0.9909 respectively. Comparing the traditional inventory model without considering lateral transshipments and maintenance ratio, and the model which only considers the maintenance ratio, the results indicate that the model offered in this paper could reduce the total cost of inventory system significantly, and provides theoretical support and method guidance for the accurate allocation of multi echelon inventory optimization for civil aircraft spare parts.
Design and Applications of Preliminary Evaluation Platform of Aerodynamic Forces for Supersonic/Hypersonic Vehicles
Authors: Cheng Feng , Tang Shuo , Zhang Dong
Published: March 2019

Rapid evaluation of aerodynamic forces is a key technology in conceptual and preliminary performance assessment and design optimization for supersonic/hypersonic vehicles, which is expected to achieve a balance between accuracy and time. In this paper, the preliminary evaluation platform of aerodynamic forces is built based on the physical theories and engineering methods. This platform computes the local velocity vector by using the streamline tracing technology, and extracts the pressure and friction coefficients by calling methods in method database. Furthermore, an example based on HL-20 is brought out. A good agreement is obtained by comparing the calculated results via CFD with the experimental. Also, a good angle of attack compatibility of streamline tracing technology is concluded. This platform has a computation time less than that via CFD and an flight range greater than that via wind tunnel. Finally, the simple flight dynamics simulation is taken out and the synergetic process is verified.
Vector Tracking Algorithm Based on Adaptive Cubature Kalman Filter
Authors: Zou Xiaojun , Lian Baowang , Dan Zesheng
Published: March 2019

In the vector tracking loop, there is a great error in the output of discriminator owing to the disturbance of noise. Cubature Kalman filter is proposed to replace the discriminator to process I/Q data and generate code phase error and the carrier frequency error in this paper. The present algorithm not only can avoid the nonlinear problem of discriminator, but also can reduce the bad effect of noise. Moreover, using cubature Kalman filter to deal with the nonlinear I/Q data is beneficial to preserve the accuracy of data processing. Because noise is unknown or time-varying, the filter should have the ability to respond to the changes of environmental noise. The innovation of measurements is used to estimate the covariance matrix of measurement noise in real time. Finally, a comparison is carried out between the present algorithm and the vector tracking algorithm based on discriminator. The test results show that the code phase error and the carrier frequency error are smaller, and the accuracy of navigation solution is also higher.
Online Cooperative Trajectory Planning for UCAV Formation in Uncertain Environment
Authors: Wang Yuan , Wei Zhenglei , Huang Changqiang , Huang Hanqiao , Zhao Kexin , Li Cong
Published: March 2019

This paper presents a local online planning method based on hp adaptive pseudospectral method to address the cooperative trajectory planning of UCAV formation in uncertain environment. First, through analyzing attacking process of UCAV formation, the cooperative trajectory planning model is built up by taking UCAV threat, task time and the number of collision and the error of ordered time as the object function. Second, in order to solve the online cooperative trajectory planning, according to real-time environment information and offline planning data, the local planning method based on hp adaptive pseudospectral method is proposed during optimizing time slice. Last but not least, the simulation results for offline and online cooperative trajectory show that the proposed method is valid and can provide cooperative trajectory with high precise control and state information.
Study on Oil-Film Interferometry Measurement Technique of Hypersonic Boundary Layer Transition
Authors: Dong Hao , Liu Shicheng , Geng Xi , Cheng Keming
Published: March 2019

Prediction of boundary layer transition is important for the design of hypersonic aircrafts. The study of boundary layer transition of hypersonic flow around a flat plate using oil-film interferometry was investigated at Φ500mm traditional hypersonic wind tunnel. In order to measure the skin friction fast and precisely on the hypersonic wind tunnel, the traditional oil-film interferometry technique is improved. A high-speed camera is used to capture the images of fringes and the viscosity of the silicon oil is modified according to the wall temperature measured by thermocouples during the test. The skin frictions of smooth surface and the surface with single square roughness element were measured. For the smooth surface, the boundary layer is laminar. However, the boundary layer transition is promoted by wake vortices induced by the roughness element. Both the results of skin friction with and without the roughness element are in good agreement with the simulation results correspondingly, indicating high accuracy of the oil film interferometry technique.
WFMHT Method of Orbit Maneuver Detection Based on Space-Based Bearing-Only Measurement
Authors: Liu Lei , Cao Jianfeng , Liu Ye
Published: March 2019

The method of orbit maneuver detection of space targets is investigated using the space-based bearing-only measurement, which aims to acquire a real-time or nearly real-time awareness of orbit maneuver in the space situation awareness. First, the model for estimating real-time motion of a space target is presented, which only uses the space-based bearing-only measurements. The innovation characteristics of the normal orbit and orbit maneuver are analyzed and compared. Second, based on the hypothesis test methods of the distribution characteristic of the stochastic sequence, the WFMHT (i.e., weighted fusion of multi hypothesis tests) method with the innovation is put forward to detect the orbit maneuver. Furthermore, the criterion of determining the weight coefficients is studied. Finally, the method is validated by numeric simulations. The results show that the highest gained success rate is up to 36% with the WFMHT method than the prevalent Chi2 method. With the WFMHT method, the detection system achieves a strengthened robustness with greatly shortened detection window. The research will be beneficial to construction of our space situation awareness system.