bluuebunny/crossref_metadata_2025 huggingface dataset:
An innovative bioresorbable gelatin based 3D scaffold that maintains the stemness of adipose tissue derived stem cells and the plasticity of differentiated neurons
Authors: Martin Catherine Ann , Radhakrishnan Subathra , Nagarajan Sakthivel , Muthukoori Shanthini , Dueñas J. M. Meseguer , Gómez Ribelles José Luis , Lakshmi Baddrireddi Subhadra , E. A. K. Nivethaa , Gómez-Tejedor José Antonio , Reddy Mettu Srinivas , Sellathamby Shanmugaapriya , Rela Mohamed , Subbaraya Narayana Kalkura
Published: May 2019

The neurons seeded on the scaffold can be used for neurological disorders as the plasticity of neurons is maintained.
A ZnS quantum dot-based super selective fluorescent chemosensor for soluble ppb-level total arsenic [As(iii) + As(v)] in aqueous media: direct assay utilizing aggregation-enhanced emission (AEE) for analytical application
Authors: Kayal Saurav , Halder Mintu
Published: May 2019

The present study is the first report on the superexclusive detection of As(iii) (LOD: 0.79 ± 0.01 ppb) and As(v) (LOD: 2.79 ± 0.02 ppb) using a ZnS-based chemosensor with LOD much lower than the MCL reported values.
Quantitative analysis of 10 classes of phospholipids by ultrahigh-performance liquid chromatography tandem triple-quadrupole mass spectrometry
Authors: Huang Qingxia , Lei Hehua , Dong Manyuan , Tang Huiru , Wang Yulan
Published: May 2019

We have developed fast and sensitive label-free quantitation with normalization of acyl chain length to quantify 10 classes of phospholipids by UHPLC-MS.
Graphite oxidation chemistry is relevant for designing cleaning strategies for radiocarbon dating samples
Authors: Joorab Doozha Amir , Poduska Kristin M.
Published: May 2019

We demonstrate that mixtures of graphite and lab-oxidized graphenic carbon materials can be separated into three individual components (graphite, graphene/graphite oxide and oxidative debris) by a series of aqueous treatments.
A simple strategy for carboxylated MWNTs as a metal-free electrosensor for anchoring the RhB CN group
Authors: Ji Lifei , Zhou Xian , Zhang Jian , Zhang Xin , Kang Weidong , Yang Fengchun
Published: May 2019

Organic dye detection requires high sensitivity, low-cost equipment, simplified procedures, and real-time capabilities; thus, electrochemical methods are gradually emerging in this field instead of chromatography.
Electric field modulated redox-driven protonation and hydration energetics in energy converting enzymes
Authors: Saura Patricia , Frey Daniel M. , Gamiz-Hernandez Ana P. , Kaila Ville R. I.
Published: May 2019

Biological energy conversion is catalysed by proton-coupled electron transfer (PCET) reactions that form the chemical basis of respiratory and photosynthetic enzymes.
An artificial solid interphase with polymers of intrinsic microporosity for highly stable Li metal anodes
Authors: Moon Gi Hyeon , Kim Hyun Jong , Chae Il Seok , Park Seul Chan , Kim Byung Su , Jang Jaeyoung , Kim Hansu , Kang Yong Soo
Published: May 2019

The unique pore structure of PIM-1 as a solid interphase can suppress transport of solvent and consequently unwanted chemical reactions at the interface of anodes.
Recognition of plastic nanoparticles using a single gold nanopore fabricated at the tip of a glass nanopipette
Authors: Nie Xiao-Lei , Liu Hai-Ling , Pan Zhong-Qin , Ahmed Saud Asif , Shen Qi , Yang Jin-Mei , Pan Jian-Bin , Pang Jie , Li Cheng-Yong , Xia Xing-Hua , Wang Kang
Published: May 2019

A single gold nanopore with high surface enhanced Raman spectroscopy (SERS) activity is fabricated on the tip of a glass nanopipette.
An H2S-activated ratiometric CO photoreleaser enabled by excimer/monomer conversion
Authors: Li Yong , Shu Yingzheng , Wang Xu , Jiao Xiaoyun , Xie Xilei , Zhang Jian , Tang Bo
Published: May 2019

Based on the excimer–monomer conversion of a pyrene–flavone hybrid, a ratiometric CO photoreleaser, PFN, was constructed for simultaneous H2S quantification and CO release in inflammatory cells.
Chiroptical sensing of unprotected amino acids, hydroxy acids, amino alcohols, amines and carboxylic acids with metal salts
Authors: Lynch Ciarán C. , De los Santos Zeus A. , Wolf Christian
Published: May 2019

Optical chirality sensing of unprotected amino acids, hydroxy acids, amino alcohols, amines and carboxylic acids based on a practical mix-and-measure protocol with readily available copper, iron, palladium, manganese, cerium or rhodium salts is demonstrated.
Ultrathin Ni(ii)-based coordination polymer nanosheets as a co-catalyst for promoting photocatalytic H2-production
Authors: Jiang Zhi-Qiang , Chen Xing-Liang , Lu Jin , Li Yu-Feng , Wen Tian , Zhang Lei
Published: May 2019

The Ni(ii) coordination polymer nanosheets were successfully exfoliated, which can be used as co-catalysts (Ni-CPNS@CdS). The optimized Ni-CPNS@CdS catalyst showed a super high visible-light photocatalytic hydrogen production activity.
A new dynamic framework with direct in situ visualisation of breathing under CO2 gas pressure
Authors: Sikiti Phumile , Bezuidenhout Charl X. , van Heerden Dewald P. , Barbour Leonard J.
Published: May 2019

Structural evidence from in situ single-crystal X-ray diffraction analysis reveals flexibility in a new non-interpenetrated pillared-layer MOF that switches between a wide-pore and a narrow-pore form.
Response of microbial membranes to butanol: interdigitationvs.disorder
Authors: Guo Jingjing , Ho James C. S. , Chin Hokyun , Mark Alan E. , Zhou Cheng , Kjelleberg Staffan , Liedberg Bo , Parikh Atul N. , Cho Nam-Joon , Hinks Jamie , Mu Yuguang , Seviour Thomas
Published: May 2019

Elucidating butanol interactions with lipid bilayers will inform membrane engineering approaches for improving butanol tolerance in industrial fermentations.
On the nature of active sites for formic acid decomposition on gold catalysts
Authors: Li Sha , Singh Suyash , Dumesic James A. , Mavrikakis Manos
Published: May 2019

Atomic scale size-sensitivity of the catalytic properties of sub-nanometer gold clusters for HCOOH decomposition.
Establishing the correlation between catalytic performance and N→Sb donor–acceptor interaction: systematic assessment of azastibocine halide derivatives as water tolerant Lewis acids
Authors: Lei Jian , Peng Lingteng , Qiu Renhua , Liu Yongping , Chen Yi , Au Chak-Tong , Yin Shuang-Feng
Published: May 2019

A series of organoantimony(iii) halide complexes with a tetrahydrodibenzo[c,f][1,5]azastibocine framework were synthesized and employed as water tolerant Lewis acid catalysts.
Polysaccharide-derived hydrogel water filter for the rapid and selective removal of arsenic
Authors: Maity Santu , Naskar Nabanita , Lahiri Susanta , Ganguly Jhuma
Published: May 2019

A low-cost furfuraldehyde–chitosan cross-linked hydrogel (FCH) has been designed and synthesized as a smart bio-adsorbent for the selective removal of As(v) from an aqueous solution using a solid liquid extraction (SLX) technique.
Quantum interferences among Dexter energy transfer pathways
Authors: Bai Shuming , Zhang Peng , Antoniou Panayiotis , Skourtis Spiros S. , Beratan David N.
Published: May 2019

We explore Dexter coupling pathway interferences in non-covalent assemblies, employing a method that enables the assessment of Dexter coupling pathway strengths, interferences, and their physical origins in the context of one-particle and two-particle (i.e., coulombic) operators.
Immunomodulatory effects ofPseudostellaria heterophyllapeptide on spleen lymphocytesviaa Ca2+/CaN/NFATc1/IFN-γ pathway
Authors: Yang Qian , Cai Xixi , Huang Muchen , Jia Lee , Wang Shaoyun
Published: May 2019

Screening and isolation ofPseudostellaria heterophyllapeptide with immunomodulatory activityviaa Ca2+/CaN/NFATc1/IFN-γ pathway.
Stainless steel mesh-GO/Pd NPs: catalytic applications of Suzuki–Miyaura and Stille coupling reactions in eco-friendly media
Authors: Feizi Mohazzab Bahareh , Jaleh Babak , Issaabadi Zahra , Nasrollahzadeh Mahmoud , Varma Rajender S.
Published: May 2019

The immobilization of palladium nanoparticles (Pd NPs) on stainless-steel mesh entails two steps via deposition of graphene oxide (GO) on the stainless-steel mesh (mesh-GO) by electrophoretic deposition (EPD), and preparation of Pd NPs by laser ablation in liquids (LAL).
A multicomponent two-step strategy for the synthesis of polysubstituted pyrrolo[3,2-c]pyridin-4-ones using a solid acid as a recyclable catalyst
Authors: Li Chunmei , Zhang Furen , Qi Chenze
Published: May 2019

A two-step strategy for the synthesis of polysubstituted pyrrolo[3,2-c]pyridin-4-ones using a solid acid as a recyclable catalyst.
Determination of chloride in crude oils by direct dilution using inductively coupled plasma tandem mass spectrometry (ICP-MS/MS)
Authors: Nelson Jenny , Poirier Laura , Lopez-Linares Francisco
Published: May 2019

The potential of using inductively coupled plasma tandem mass spectrometry, ICP-MS/MS, (also known as triple quadrupole ICP-MS) for the determination of chloride in petroleum crude samples following direct dilution was investigated.
Inhibiting bacterial secretion systems in the fight against antibiotic resistance
Authors: Boudaher Elizabeth , Shaffer Carrie L.
Published: May 2019

The search for new ammunition to combat antibiotic resistance has uncovered diverse inhibitors of the bacterial type IV secretion system.
Chemistries and capabilities of photo-formable and photoreversible crosslinked polymer networks
Authors: Hughes T. , Simon G. P. , Saito K.
Published: May 2019

We investigate how the application of photocuring has addressed unique challenges through inherent benefits of the methodology or inventive chemistries.
Fabrication of a magnetic metal–organic framework molecularly imprinted polymer for extraction of anti-malaria agent hydroxychloroquine
Authors: Parvinizadeh Farnaz , Daneshfar Ali
Published: May 2019

A new magnetic metal–organic framework molecularly imprinted polymer was synthesized by the sol–gel method for the determination of hydroxychloroquine sulfate.
Analysis of volatile organic compounds in environmental matrices by nitrogen-assisted headspace solid-phase extraction
Authors: Gao Jing , Zhang Chuntao , Cheng Zheng , Liu Donghui , Zhou Zhiqiang , Wang Peng
Published: May 2019

A novel pretreatment method named nitrogen-assisted headspace solid-phase extraction (NA/HS-SPE) was developed for the analysis of volatile organic pollutants in water, sediment, honey, and juice.
A red-emissive mitochondrial probe for imaging of the viscosity in living cells
Authors: Wang Hui , Cai Fengze , Zhou Le , He Jing , Feng Dexiang , Wei Yan , Feng Zhijun , Gu Xiaoxia , Kajsa Uvdal , Hu Zhangjun
Published: May 2019

L can exclusively stain mitochondria and monitor the mitochondrial viscosity changes.
Graphene quantum dot-functionalized three-dimensional ordered mesoporous ZnO for acetone detection toward diagnosis of diabetes
Authors: Liu Wei , Zhou Xiangyu , Xu Lin , Zhu Shidong , Yang Shuo , Chen Xinfu , Dong Biao , Bai Xue , Lu Geyu , Song Hongwei
Published: May 2019

Self-assembled GQD-modified 3DOM ZnO was developed as a highly sensitive sensor for trace acetone detection toward the diagnosis of diabetes.
Polydopamine-decorated tobacco mosaic virus for photoacoustic/magnetic resonance bimodal imaging and photothermal cancer therapy
Authors: Hu He , Yang Qi , Baroni Simona , Yang Hong , Aime Silvio , Steinmetz Nicole F.
Published: May 2019

The Gd-TMV–PDA nanotheranostic reagents demonstrated highly r1-relaxivity of ∼80 mM−1 s−1 at 60 MHz, strong near-infrared absorption with high photothermal conversion efficiency (28.9%), excellent photoacoustic contrast and good biocompatibility.
Induction of mTOR-dependent autophagy by WS2 nanosheets from both inside and outside of human cells
Authors: Zhou Xiaofei , Yan Bing
Published: May 2019

Both the cell surface adhesion and cell internalization of WS2 nanosheets induce mTOR-dependent autophagy.
The Lossen rearrangement from free hydroxamic acids
Authors: Thomas Mikaël , Alsarraf Jérôme , Araji Nahla , Tranoy-Opalinski Isabelle , Renoux Brigitte , Papot Sébastien
Published: May 2019

During more than a century, the Lossen rearrangement was supposed to occur exclusively in the presence of stochiometric amount of activating reagents. Very recently, it was demonstrated that the Lossen rearrangement can take place directly from free hydroxamic acids offering a renewal of interest for this reaction.
Identification of crucial bottlenecks in engineered polyketide biosynthesis
Authors: Grote Marius , Kushnir Susanna , Pryk Niclas , Möller David , Erver Julian , Ismail-Ali Ahmed , Schulz Frank
Published: May 2019

Quo vadis combinatorial biosynthesis: STOP signs through substrate scope limitations lower the yields in engineered polyketide biosynthesis using cis-AT polyketide synthases.
Synthesis of delayed-emissive poly(2,7-carbazole)s having an anchored triazine pendant at the N-position
Authors: Aso Fumihiro , Kawashima Hidehisa , Fujiki Michiya , Kijima Masashi
Published: May 2019

The design, synthesis, and characterization of delayed-emissive poly(2,7-carbazole)s having an anchored triazine pendant at the N-position.
Kinetics and mechanism for thermal and photochemical decomposition of 4,4′-azobis(4-cyanopentanoic acid) in aqueous media
Authors: Zhou Yanyan , Zhang Zhengbiao , Postma Almar , Moad Graeme
Published: May 2019

The two diastereoisomers of 4,4′-azobis(4-cyanopentanoic acid) decompose at different rates in aqueous media. The major products (>50%) are amides produced by trapping the ketenimines formed by C–N coupling.
Multivariate optimization of optical properties of CdSe quantum dots obtained by a facile one-pot aqueous synthesis
Authors: Viegas Isabelle Moraes Amorim , Santos Beate Saegesser , Fontes Adriana , Pereira Giovannia Araujo de Lima , Pereira Claudete Fernandes
Published: May 2019

Four parameters are simultaneously optimized to provide a simple, fast and reproducible synthesis procedure to obtain high-quality CdSe quantum dots.
Activity enhancement of layered cobalt hydroxide nanocones by tuning interlayer spacing and phosphidation for electrocatalytic water oxidation in neutral solutions
Authors: Qin Ruinan , Wan Hao , Liu Xiaohe , Chen Gen , Zhang Ning , Ma Renzhi , Qiu Guanzhou
Published: May 2019

We explored the electrocatalytic performance of cobalt hydroxide nanocones in neutral solutionsviatuning the interlayer spacing and phosphidation.
Alkynogenic fragmentation
Authors: Yang Jingyue , Hoang Tung T. , Dudley Gregory B.
Published: May 2019

Fragmentation reactions that generate alkynes in conjunction with C–C bond cleavage require special considerations but can produce high-value alkyne building blocks for organic synthesis.
Synthetic approach to skeletally diverse nitrogen heterocycles from dicyano-2-methylenebut-3-enoates
Authors: Zhang Xiang , Huang Qing-Fei , Zou Wen-Lin , Li Qing-Zhu , Feng Xin , Jia Zhi-Qiang , Liu Yue , Li Jun-Long , Wang Qi-Wei
Published: May 2019

Divergent synthesis of three types of azaheterocycles, including vinylaziridines, pyrroline and 2-aminopyridines, has been achieved through [2 + 1], formal-[4 + 1] and [5 + 1] annulations.
A reduced graphene oxide–borate compound-loaded melamine sponge/silicone rubber composite with ultra-high dielectric constant
Authors: Zhang Hong , Ma Chuan-Guo , Dai Pei-Bang , Zhang Jian
Published: May 2019

A reduced graphene oxide–borate compound-loaded melamine sponge/silicone rubber composite with the ultra-high dielectric constant of 2.71 × 104.
Early stages of phase selection in MOF formation observed in molecular Monte Carlo simulations
Authors: Wells Stephen A. , Cessford Naomi F. , Seaton Nigel A. , Düren Tina
Published: May 2019

Clusters produced in simulations of MOF assembly at metal : ligand ratios of (a) 5 : 1 and (b) 1 : 1 with identical interaction potentials.
Translation of ceragenin affinity for bacteria to an imaging reagent for infection
Authors: Bandara Nilantha , Li Yubo , Diebolder Philipp , Mpoy Cedric , Gu Xiaobo , Khanal Pitambar , Deng Shenglou , Rogers Buck E. , Savage Paul B.
Published: May 2019

Infection imaged via autoradiography with ceragenin conjugated to a copper radiolabel.
Inhibition of metal-induced amyloid β-peptide aggregation by a blood–brain barrier permeable silica–cyclen nanochelator
Authors: Wang Jinzhuan , Wang Kun , Zhu Zhenzhu , He Yafeng , Zhang Changli , Guo Zijian , Wang Xiaoyong
Published: May 2019

A BBB-passable nanoscale silica–cyclen chelator effectively reduces the metal-induced Aβ aggregates and related ROS, thereby decreasing the neurotoxicity of Aβ.
The destructive spontaneous ingression of tunable silica nanosheets through cancer cell membranes
Authors: Bandyopadhyay Arghya , Yadav Priya , Sarkar Keka , Bhattacharyya Sayan
Published: May 2019

Beyond conventional therapies, the sharp edge ingress of ‘thin’ silica nanosheets treats cancerviamechanical scalpelling, albeit with limited oxidative stress.
Revisiting a classical redox process on a gold electrode by operando ToF-SIMS: where does the gold go?
Authors: Hua Xin , Xia Hai-Lun , Long Yi-Tao
Published: May 2019

Our results indicated that a gold electrode participates in the redox reaction of [Fe(CN)6]3/4− by competing with it to form Au(CN)2−.
Optimal coordination-site exposure engineering in porous platinum for outstanding oxygen reduction performance
Authors: Cheng Han , Liu Si , Hao Zikai , Wang Jingyu , Liu Bojun , Liu Guangyao , Wu Xiaojun , Chu Wangsheng , Wu Changzheng , Xie Yi
Published: May 2019

Optimal coordination-site exposure engineering in porous platinum brings ultrahigh activity and durability for the fuel cell oxygen reduction reaction.
A facile and controllable, deep eutectic solvent aided strategy for the synthesis of graphene encapsulated metal phosphides for enhanced electrocatalytic overall water splitting
Authors: Mou Hongyu , Wang Jinfang , Yu Dongkun , Zhang Deliang , Lu Fu , Chen Lei , Wang Debao , Mu Tiancheng
Published: May 2019

A facile, deep eutectic solvent aided strategy for the preparation of graphene encapsulated phosphides for enhanced electrocatalytic overall water splitting was proposed.
A multi-functional interface derived from thiol-modified mesoporous carbon in lithium–sulfur batteries
Authors: Li Yun , Murphy Ian A. , Chen Ying , Lin Francis , Wang Xiang , Wang Shanyu , Hubble Dion , Jang Sei-Hum , Muller Karl T. , Wang Chongmin , Jen Alex K.-Y. , Yang Jihui
Published: May 2019

Li–S batteries hold great promise as the utility of a thiol-based interface facilitates LiPS-trapping and improves the electrolyte wetting.
Enhanced photoexcited carrier separation in CdS–SnS2 heteronanostructures: a new 1D–0D visible-light photocatalytic system for the hydrogen evolution reaction
Authors: Chava Rama Krishna , Do Jeong Yeon , Kang Misook
Published: May 2019

CdS–SnS2 1D–0D core–shell heteronanostructures were designed for an efficient visible-light photocatalytic H2 evolution reaction.
Passivation of aluminum current collectors in non-aqueous carbonate solutions containing sodium or potassium hexafluorophosphate salts
Authors: Konarov Aishuak , Kim Hee Jae , Yashiro Hitoshi , Myung Seung-Taek
Published: May 2019

The AlF3 layer on the surface of aluminum foil is stable up to 5 V vs. Na+/Na or K+/K.
Optical features of hybrid molecular/biological-quantum dot systems governed by energy transfer processes
Authors: Wax Terianna J. , Zhao Jing
Published: May 2019

The impact of energy transfer processes on the optical profiles of heteroassemblies with quantum dots as a nano-scaffold are highlighted.
Color-tunable Eu2+,Eu3+ co-doped Ca20Al26Mg3Si3O68 phosphor for w-LEDs
Authors: An Zhengce , Liu Wei , Song Yanhua , Zhang Xiangting , Dong Rujia , Zhou Xiuqing , Zheng Keyan , Sheng Ye , Shi Zhan , Zou Haifeng
Published: May 2019

Excellent color-tunable Eu2+,Eu3+ co-doped Ca20Al26Mg3Si3O68 materials have been prepared and their structure related luminescence properties have been studied. Combined with electroluminescent chip, Ca20Al26Mg3Si3O68:Eu2+,Eu3+ shows multicolour emission.
Leakage rate‐based untrustworthy relay selection with imperfect channel state information: the outage and security trade‐off analysis
Authors: Ozduran Volkan
Published: May 2019

This study investigates the effects of the imperfect channel state information on the leakage rate‐based untrustworthy relay selection strategies. The investigation considers that the channel state information is imperfect because of the channel estimation errors and also the feedback delay with time‐variant channels. The investigation also considers three different types of leakage rate‐based selection strategies, which are half‐duplex, full‐duplex, and hybrid. The investigation also considers a dual‐hop one/two‐way amplify‐and‐forward‐based half‐/full‐duplex wireless relaying network in the system model. In addition, in order to mitigate the information leakage, a finite number of friendly jammers are affecting the untrustworthy relay terminals. According to analytical, asymptotic, and Monte–Carlo simulation results, the leakage rate‐based selection strategies achieve cooperative diversity order in high signal‐to‐noise ratio regimes. The channel estimation error causes system coding gain losses in low signal‐to‐noise ratio regimes. The feedback delay degrades the achievable diversity order from M to 0 and also causes system coding gain losses in high signal‐to‐noise ratio regimes. In addition, the friendly jammers and loop‐interference also degrade the achievable diversity order and also cause system coding gain losses in high signal‐to‐noise ratio regimes.
3D non‐stationary geometry‐based multi‐input multi‐output channel model for UAV‐ground communication systems
Authors: Zhu Qiuming , Wang Yawen , Jiang Kaili , Chen Xiaomin , Zhong Weizhi , Ahmed Naeem
Published: May 2019

Unmanned aerial vehicles (UAVs) with multi‐input–multi‐output technologies are considered as a promising platform to provide future high‐speed wireless communication services. In this study, considering three‐dimensional (3D) antenna arrays and 3D arbitrary trajectories of the UAV and mobile terminal, the authors propose a new 3D non‐stationary geometry‐based stochastic channel model for UAV‐ground communication systems. Under 3D non‐isotropic scattering scenarios, the computation and optimisation methods of time‐variant channel parameters are investigated. In addition, the theoretical statistical properties such as the autocorrelation function, cross‐correlation function, Doppler power spectrum density, level‐crossing rate, and average fading duration are analysed and derived. Finally, the usefulness of the proposed model as well as theoretical derivations are verified by the comparison between theoretical, simulated, and measured results.
Dielectric and metallic jointly 3D‐printed mmWave hyperbolic lens antenna
Authors: Zhang Bing , Guo Yong‐Xin , Guo Qingyi , Wu Li , Ng Kung Bo , Wong Hang , Zhou Yanping , Huang Kama
Published: May 2019

A dielectric–metallic jointly three‐dimensional (3D) printed V‐band (50–75 GHz) lens antenna with preliminary surface roughness modelling is proposed. It takes full advantage of both the dielectric and metallic 3D printing technologies which help effectively to control the cost of the lens antenna. The stereolithography apparatus is used to form the lens using Somos Imagine 8000 resin, while the selective laser melting is used to fabricate the feed horn using aluminium alloy. A λ0/4 matching layer is adopted between the feed and lens for reduced reflection. The surface roughness of the lens and the feed horn are characterised under a surface profilometer. Owing to the material and process, the surface roughness of the 3D‐printed device demonstrates distinctive properties. A preliminary conjecture is made on the surface roughness distribution of 3D‐printed devices that are helpful to predict roughness‐related performance degradation. The antenna is characterised by electromagnetically and materialwise. It has impedance bandwidth of |S11|<−20 dB from 50 to 70 GHz with the in‐band gain >32 dBi and symmetric radiation patterns on both E and H planes, which agrees well with simulation.
In situ synthesis of high dielectric constant GNPs/PBO nanocomposites with enhanced thermostability
Authors: Chen Yi , Kong Zhen , Chen Wenqi , Xiao Lv , Yuan Yong , Li Zhongquan , Zhuang Qixin
Published: May 2019

Graphite nanoparticles (GNPs) were introduced into poly(p‐phenylene benzobisoxazole) (PBO) matrix to produce composites via in situ polymerisation. Films of various composites were fabricated through the solution casting method in methanesulfonic acid (MSA) with the help of two sand core plates. The interlayer spacing of GNPs increased slightly confirmed by XRD as a result of an expanding effect caused by continuously formed PBO chains between the graphene nanosheets of GNPs during polymerisation. Also, due to the uniform dispersion of GNPs into PBO matrix, composite films exhibited an improved tensile strength (258 MPa, 72% higher than that of pure PBO) with 5 wt% loading of GNPs fillers. The initial decomposition temperature of the composite is ∼630°C. Besides, benefitting from the interfacial polarisation in this conductive filler/polymer system, the dielectric constant of the composites with 10 wt% loading of GNPs reached 6.96, which were over two times higher than that of pristine PBO polymer (2.91).
Ultra‐high step‐up two‐input DC–DC converter with lower switching losses
Authors: Mohseni Parham , Hossein Hosseini Seyed , Maalandish Mohammad , Sabahi Mehran
Published: May 2019

In this study, a novel isolated ultra‐high step‐up two‐input DC–DC converter with low‐voltage stress across semiconductors is presented. In the proposed converter, outputs are isolated from the inputs by a high‐frequency transformer and the leakage inductance of the transformer is used to soft switching (zero‐current switching) of the power switches when they are turned‐on and alleviate the reverse recovery problems of the diodes. This converter can be operated as an interleaved single‐input converter with a 180° phase shift. The converter benefits from the advantages of both the conventional boost converter and diode‐capacitor voltage multiplier (VM) stages. The primary side of the transformer consists of two‐input cells based on the conventional boost converter and the secondary side consists of diode‐capacitor VM stages which are used to increase the voltage gain and decrease the nominal voltage stress across semiconductors. To confirm the converter performance, the mathematical analysis and simulation result are presented, in addition, the comparison between the proposed converter and other converters which are presented in recent studies is presented. An experimental prototype 410 V/280 W of the converter with 40 and 45 V input voltages is provided to illustrate the correct operation of the presented converter.
New modulation scheme and voltage balancing control of modular multilevel converters for modern electric ships
Authors: Ronanki Deepak , Williamson Sheldon S.
Published: May 2019

The distinctive features such as fault‐tolerability, modularity, power and voltage scalability have propelled modular multilevel converters (MMCs) as one of the emerging power converter topologies for marine applications. Pulse‐width modulation (PWM) schemes are widely used to control the MMCs due to their good control capability and ability to operate at higher switching frequencies. However, the required number of carriers for gating signal generation drastically increases with the submodule count per arm in an MMC. Moreover, these carriers should be accurately synchronised with each other to generate high power quality waveforms. However, it is hard to establish accurate synchronisation between these carriers due to the sampling issues, memory limitations, and computational delays. In addition, the MMC demands reconfiguration of PWM carriers and control strategy for voltage scalability and retrofit applications. To avoid these issues, a simple PWM scheme using one carrier is proposed in this study. The main advantage of the proposed scheme is an easy extension to the n‐level MMC with a wide range of output voltage levels. The effectiveness of the proposed PWM scheme along with the capacitor voltage balancing control is demonstrated through detailed simulations and verified experimentally under steady‐state and dynamic conditions.
Modelling and control of DC–DC Ćuk converter with and voltage multiplier cells for PV applications
Authors: Miguel Klein Faistel Tiago , Henrique Illa Font Carlos , Andrade António Manuel Santos Spencer , Lúcio da Silva Martins Mário
Published: May 2019

This study proposes the modelling and control of a Ćuk converter with reduced redundant power processing and voltage multiplier for photovoltaic (PV) applications. The converter makes use of a perturb & observe algorithm to extract the maximum power of a single PV panel. The proposed converter is derived from the association of the and voltage multiplier cells in order to achieve the high step‐up voltage gain. This association allows a high‐voltage gain, low‐voltage and current stresses on the semiconductors. Experimental results are presented to validate the proposal a prototype with the input of 37.4 V, output voltage of 400 V and rated input power of 200 W.
Strategies for combined operation of PV/storage systems integrated into electricity markets
Authors: Carriere Thomas , Vernay Christophe , Pitaval Sebastien , Neirac Francois‐Pascal , Kariniotakis George
Published: May 2019

The increasing share of photovoltaic (PV) power in the global energy mix presents a great challenge to power grid operators. In particular, PV power's intermittency can lead to mismatches between energy production and expectation. Battery energy storage systems (BESSs) are often put forward as a good technological solution to these problems, as they can mitigate forecast errors. However, the investment cost of such systems is high, which questions the benefits of using these systems in operational contexts. In this work, we compare several strategies to manage a PV power plant coupled with a BESS in a market environment. They are obtained by stochastic optimisation using a model predictive control approach. This study proposes an approach that takes into account the aging of the BESS, both at the day‐ahead level and in the real‐time control of the BESS, by modelling the cost associated with BESS usage. As a result, the BESS arbitrates between compensating forecast errors and preserving its own life expectancy, based on both PV production and price scenarios derived from probabilistic forecasts. A sensitivity analysis is also carried out to provide guidelines on the optimal sizing of the BESS capacity, depending on market characteristics and BESS prospective costs.
Proposal of a health care network based on big data analytics for PDs
Authors: Carnimeo Leonarda , Trotta Gianpaolo Francesco , Brunetti Antonio , Cascarano Giacomo Donato , Buongiorno Domenico , Loconsole Claudio , Di Sciascio Eugenio , Bevilacqua Vitoantonio
Published: May 2019

Health care networks for Parkinson's disease (PD) already exist and have been already proposed in the literature, but most of them are not able to analyse the vast volume of data generated from medical examinations and collected and organised in a pre‐defined manner. In this work, the authors propose a novel health care network based on big data analytics for PD. The main goal of the proposed architecture is to support clinicians in the objective assessment of the typical PD motor issues and alterations. The proposed health care network has the ability to retrieve a vast volume of acquired heterogeneous data from a Data warehouse and train an ensemble SVM to classify and rate the motor severity of a PD patient. Once the network is trained, it will be able to analyse the data collected during motor examinations of a PD patient and generate a diagnostic report on the basis of the previously acquired knowledge. Such a diagnostic report represents a tool both to monitor the follow up of the disease for each patient and give robust advice about the severity of the disease to clinicians.
Seven days in Chile: Impact of the 2011 Puyehue-Cordon Caulle volcanic eruption on GPS ionospheric delay
Authors: Jukić Oliver , Sikirica Nenad , Rumora Ivan , Filić Mia
Published: May 2019

Satellite navigation is a global utility and an essential component of national infrastructure. Disruptions of GNSS PNT services may be considered a threat to society and civilisation in general. Natural hazards may cause the conditions that disrupt or temporarily deny GNSS PNT services. As a contributor to ionospheric dynamics, volcanic activity is considered a source of GNSS positioning performance degradation. Here we studied the 2011 Puyehue-Cordon Caulle event, the largest 21st century volcanic eruption so far, in terms of its contribution to formation of Total Electron Content (TEC), the source of ionosphere-caused GNSS positioning error, and the effects the event made on GPS positioning accuracy. TEC values were derived from dual-frequency GPS observations collected experimentally at the International GNSS Service Network reference stations in Santiago, central Chile closest to the Puyehue-Cordon Caulle volcano. We identified considerable anomalous behaviour of TEC dynamics prior to, during and after the volcanic eruption, and examined the extent to which it affected GPS positioning accuracy. The research presented here will continue with the aim of characterisation of TEC anomalous dynamics around the eruption, and its effects on GNSS positioning performance.
Comparison of Sea Surface Variation Derived from Global Navigation Satellite System (GNSS) and Co-tidal in Java Sea
Authors: Guruh Pratomo Danar , Khomsin  , Syaputra Khariz
Published: May 2019

Tide represents the vertical variation of sea surface. This parameter plays important rules in bathymetric survey. The conventional method to observe the sea surface variation is by using tide pole. Nowdays, a Global Navigation Satellite System (GNSS) can be used as a means to measure the variation of sea surface as it provides high accuracy coordinates. In this research, the vertical component of GNSS was utilized to analyze the variation of sea surface. The distance between tidal stations and the survey area can be a constrain to the depth reduction because its tidal zoning. The traditional tidal zoning is a discrete model. This can be minimalized using a co-tidal chart. In this research, the vertical variation of sea surface from GNSS and co-tidal chart approachs were examined and compared to the conventional method. The comparative analysis was performed with Root Mean Square Error (RMSE). The maximum and minimum RMSE during 3 days period between the GNSS and conventional approach are 0.246 m and 0.051 m, respectively. Whereas, the maximum and minimum RMSE between the co-tidal chart model and the conventional approach at the same time are 0.286 m and 0.109 m.
Variability and Performance of Short to Long-Range Single Baseline RTK GNSS Positioning in Indonesia
Authors: Gumilar Irwan , Bramanto Brian , Rahman Fuad F. , Hermawan I Made D. A.
Published: May 2019

As the modernized Global Navigation Satellite System (GNSS) method, Real Time Kinematic (RTK) ensures high accuracy of position (within several centimeters). This method uses Ultra High Frequency (UHF) radio to transmit the correction data, however, due to gain and power issues, Networked Transport of RTCM via Internet Protocol (RTCM) is used to transmit the correction data for a longer baseline. This Research aims to investigate the performance of short to long-range single baseline RTK GNSS (Up to 80 KM) by applying modified LAMBDA method to resolve the ambiguity in carrier phase. The RTK solution then compared with the differential GNSS network solution. The results indicate that the differences are within RTK accuracy up to 80 km are several centimeter for horizontal solution and three times higher for vertical solution.
Trilateration Approaches for Indoor Wi-Fi Positioning
Authors: Retscher Guenther , Kleine Jonathan , Whitemore Lisa
Published: May 2019

In smartphones several sensors and receivers are embedded which enable positioning in Location-based Services and other navigation applications. They include GNSS receivers and Wireless Fidelity (Wi-Fi) cards as well as inertial sensors, such as accelerometers, gyroscope and magnetometer. In this paper, indoor Wi-Fi positioning is studied based on trilateration. Three methods are investigated which are a resection, a calculation of the center of gravity point and a differential approach. The first approach is a commonly employed resection using the ranges to the Wi-Fi Access Points (APs) as radii and intersect the circles around the APs. In the second method, the center of gravity in a triangle of APs is calculated with weighting of the received signal strength (RSS) of the Wi-Fi signals. The third approach is developed by analogy to Differential GNSS (DGNSS) and therefore termed Differential Wi-Fi (DWi-Fi). Its advantage is that a real-time modeling of the temporal RSS variations and fluctuations is possible. For that purpose, reference stations realized by low-cost Raspberry Pi units are deployed which serve at the same time as APs. The experiments conducted in a laboratory and entrance of an office building showed that position deviations from the ground truth of around 2 m are achievable with the second and third method. Thereby the positioning accuracies depend mainly on the geometrical point location in the triangle of APs and reference stations and the RSS scan duration.
Stereo visual-inertial odometry with an online calibration and its field testing
Authors: Jung Jae Hyung , Heo Sejong , Park Chan Gook
Published: May 2019

In this paper, we present a visual-inertial odometry (VIO) with an online calibration using a stereo camera in planetary rover localization. We augment the state vector with extrinsic (rigid body transformation) and temporal (time-offset) parameters of a camera-IMU system in a framework of an extended Kalman filter. This is motivated by the fact that when fusing independent systems, it is practically crucial to obtain precise extrinsic and temporal parameters. Unlike the conventional calibration procedures, this method estimates both navigation and calibration states from naturally occurred visual point features during operation. We describe mathematical formulations of the proposed method, and it is evaluated through the author-collected dataset which is recorded by the commercially available visual-inertial sensor installed on the testing rover in the environment lack of vegetation and artificial objects. Our experimental results showed that 3D return position error as 1.54m of total 173m traveled and 10ms of time-offset with the online calibration, while 6.52m of return position error without the online calibration.
Optimization of Ground Control Point (GCP) and Independent Control Point (ICP) on Orthorectification of High Resolution Satellite Imagery
Authors: Hariyanto Teguh , Kurniawan Akbar , Pribadi Cherie Bhekti , Amin Rizal Al
Published: May 2019

In the rapidly evolving technology era, various survey methods have been widely used one of them by remote sensing using satellite. It is known that the satellite image recording process is covered by rides (satellites) moving over the Earth's surface at hundreds of kilometers, causing satellite imagery to have geometric distortion. To reduce the effect of geometric distortion of objects on the image, geometric correction by orthorectification is done. Pleiades is a satellite of high resolution satellite image producer made by Airbus Defense & Space company. The resulting satellite imagery has a 0.5 meter spatial resolution. As a reference for the more detailed space utilization activities of space utilization arranged in the Regional Spatial Plans, Detailed Spatial Plans was created with the 1: 5000 scale map which has been governed by the Geospatial Information Agency. In the process of orthorectifying satellite imagery for this 1: 5000 scale map, ground control or Ground Control Point (GCP) is used for geometric correction and Digital Elevation Model (DEM) data. In this research, the optimal number of GCP usage for orthorectification process in Rational Function method is 21 GCP using 2nd order polynomial
A New Method for converting Slant Ionospheric Delays to Vertical for SBAS Ionospheric corrections
Authors: Choi Bongkwan , Han Deokhwa , Kim Hwigyeom , Kee Changdon
Published: May 2019

SBAS gives ionospheric correction data to GNSS users for more accurate positioning. SBAS uses obliquity factor of thin shell model to convert slant ionospheric delays to vertical delays which is not precise especially at lower elevation angle. This paper suggests a new method for estimating the vertical delays which are needed for generating the ionospheric corrections. The new method uses Chapman profile assumption by which the vertical electron density distribution can be modeled. It is also assumed that Chapman profile’s parameters are given and the vertical ionospheric delay can be linearly modeled. We divided ionosphere into multi-layer and mapped ionospheric vertical delays with a linear function. Converting vertical delays of each layer to slant delays, we can set a linear equation for the vertical ionospheric delay at IPP. We used IRI model to get information about ionosphere for simulation to verify our new method. Estimation error of vertical ionospheric delay at IPP was decreased about 40% in average when using our new method.
Performance Analysis of Relative Positioning using GPS and BDS signals
Authors: Noh Jae Hee , Lee Sun Yong , Lim Deok Won , Jo Gwang Hee , Lee Jin Hyuk , Lee Sang Jeong
Published: May 2019

In general, the satellite signal received by GNSS receivers has errors such as satellite clock error, orbit error, ionospheric delay and tropospheric delay. In environments where high positioning accuracy is required, these error factors can be eliminated by using relative positioning using code measurements with carrier phase measurements. If relative positioning is performed using carrier phase measurements, it is possible to have positioning accuracy of cm level. In this paper, we analyse the positioning accuracy of relative positioning using the L1 signal of GPS and BDS. For this study, we collect GPS and BDS signal using two low-cost receivers. We also designed a software-based platform to perform the relative positioning. Finally, we analyse relative positioning accuracy for GPS/BDS integrated system as well as relative positioning accuracy for GPS and BDS.
Earthquake Monitoring Using Variometric GPS Data Processing
Authors: Cahyadi Mokhamad Nur , Rahayu Ririn Wuri , Muslim Buldan
Published: May 2019

Variometric Approach for Standalone Engine Displacement Analysis (VADASE) is a technique used in seismology purposes using GPS measurements. VADASE is used to determine the small displacement from the earthquake. The VADASE L1 solution is using the klobuchar ionospheric model. In this study VADASE was used in earthquakes with magnitudes> 7 to> 9 righter scales. In the scale of the earthquake category> 9 used Indian Ocean earthquake of December 26, 2016 with the strength of 9.1 SR by using the closest SAMP station and the Japanese Tohoku earthquake of March 11, 2011 with a power of 9.1 SR using 4 different stations namely MIZU, KMSV, TSK2 and Knii . The earthquake category with a scale of> 8 SR is the offshore earthquake Bio Bio, Chile on February 27, 2010 with a power of 8.8 SR using 2 stations namely ANTC and SANT, the Bengkulu Indonesia earthquake on 12 September 2007 with a power of 8.4 SR using the SAMP station, an illaper earthquake, chile September 16 2015 with 8.3 SR using SANT station, and Tres Piscos earthquake Mexico on September 8, 2017 with a power of 8.2 SR using IENG station. Earthquake with a strength of> 7 SR, namely the amberlay-New Zealand earthquake on November 13, 2016 with a strength of 7.8 SR using MRLL and WGTN stations, Puerto quello-chile earthquake on December 25, 2016 with a strength of 7.6 SR using COYQ station, Java sea earthquake -Indonesia on 8 August 2007 with 7.5 SR power using BAKO station and ayula mexico earthquake on 19 september 2017 with 7.1 SR power using INEG station. From the results of VADASE, the farthest distance from the epicenter to the observation station is 1100 km (INEG station) and the closest distance is 95 km (BAKO station). The highest speed is 0.12 m / s after 5 minutes from the earthquake in the earthquake Offshore Bio Bio-Chile 2010 uses the SANT station and the lowest speed is 0.006 m / s after 10 minutes from the earthquake in the 2007 Bengkulu earthquake using the SAMP station. Whereas in the other earthquakes was the 2011 Tohoku earthquake with a speed of 0.06 m / s after 1 minute using MIZU station, the amberley-New Zealand earthquake 2016 with a speed of 0.015 m / s after 1 minute using the MRLI satellite, Puerto quelloearthquake Chile 2016 with a speed of 0.025 m / s after 40 minutes using the COYQ satellite.
Zenith Wet Delay (ZWD) Seasonal Correlation with Rainfall in Cikapundung River Discharge, North Bandung Region, Indonesia
Authors: Kuntjoro Wedyanto , Wijaya D.D. , Pramansyah A. , Tanuwijaya Z.A.J. , Pradipta Dhota
Published: May 2019

In a GPS survey study, the biases produced by the ionosphere and troposphere layers are known as ionospheric biases and troposphere bias. The distance deviation due to the slowing travel time of GPS signals in troposphere is commonly referred to as Zenith Tropospheric Delay (ZTD). The magnitude of this ZTD can also be used to characterize and analyze the troposphere conditions around the GPS observation area. This can be done by separating the wet delay component from ZTD, so as to obtain Zenith Wet Delay (ZWD) and dry component so as to obtain Zenith Hydrostatic Delay (ZHD). The total moisture content in the troposphere (precipitable water vapor, PWV) of an area can be estimated based on the bias characteristics of zenith wet delay (ZWD). The ZWD pattern is very important in the study of atmospheric water cycles which are associated with rainfall patterns and flood events. The methods used in the research include preliminary data processing and estimation of ZTD value using RTKLIB 2.4.2. This article analyzes the correlation between ZWD, rainfall and Cikapundung river discharge in the North Bandung Region (KBU), based on the daily average data in the 2011-2015 observation period. Based on the reconstruction of harmonic components, it was found that the seasonal pattern of river discharge is correlating with the seasonal pattern of rainfall and moisture content in the troposphere. The pattern of the three variables is strongly influenced by the Asian and Australian Monsoon exchanges phenomena. Linear correlation between ZWD and river discharge exhibits clear results, which is based on the Pearson correlation value is 88.84% with a 95% confidence level using t-student statistic. Based on cross-spectrum analysis, the three variables are dominated by the seasonal cycle of one-year monsoon (annual) and the six-month cycle phenomenon (semi-annual).
Suitability Conservation Types Analysis of Panglima Besar Soedirman Reservoir
Authors: Brontowiyono Widodo , Wardhana Rizal Kartika , Wacano Dhandhun
Published: May 2019

Mrica Reservoir located in Banjarnegara Regency is amultipurpose reservoir. Based on the report of PT Indonesia Power UnitPembangkitan (UP) Mrica in 2016, the sediment of Mrica Reservoir hasentered the critical phase as it reached 114.25 million m3 and the value ofland-cover index of Mrica reservoir was 80% of the total watershed areawith the average sedimentation rate reaching 4.09 million m3 per year. Itis estimated that the reservoir will be full of sediment by 2021. The maincause of the high rate of sedimentation in Mrica reservoir is the changes inland use and agricultural-plantation activities in the upper river areas andalong the river flow of Serayu River, Merawu River, and Lumajang River. This study aimed to determine the appropriate type of conservation forMrica Reservoir. The method used was the Analytical Hierarchy Process(AHP), in which the determination of conservation efforts was based onsecondary data and observation. According to the current condition ofMrica Reservoir, the planned conservation efforts include two types, namely non-structural conservation and structural conservation. If theconservation begins in 2019, the total sediment in 2021 will decrease to74% and it is predicted that the sediment will be exhausted by 2056.