bluuebunny/crossref_metadata_2025 huggingface dataset:
Formal [3+2] cycloaddition of vinylcyclopropane azlactones to enals using synergistic catalysis
Authors: Kamlar Martin , Franc Michael , Císařová Ivana , Gyepes Róbert , Veselý Jan
Published: March 2019

The present study reports the asymmetric cyclization of enals with vinylcyclopropane azlactones efficiently catalyzed by the combination of achiral Pd(0) complexes and chiral secondary amines.
The study of rhenium pentacarbonyl complexes using single-atom chemistry in the gas phase
Authors: Wang Yang , Cao Shiwei , Zhang Jicai , Fan Fangli , Yang Jie , Haba Hiromitsu , Komori Yukiko , Yokokita Takuya , Morimoto Kouji , Kaji Daiya , Wittwer Yves , Eichler Robert , Türler Andreas , Qin Zhi
Published: March 2019

Two experiments prove Re pentacarbonyl could exist stably in the gas phase at the single-atom level.
Managing optical heating via Al3+-doping in Er3+:SrF2 powder phosphors prepared by combustion synthesis
Authors: Rakov Nikifor , Guimarães Renato B. , Maciel Glauco S.
Published: March 2019

Internal temperature rise due to optical heating in Er3+-doped SrF2 powder phosphors with and without Al3+ ions.
Photodegradation of pharmaceutical compounds in partially nitritated wastewater during UV irradiation
Authors: Hora Priya I. , Novak Paige J. , Arnold William A.
Published: March 2019

Photosensitized destruction of pharmaceuticals is facilitated by UV exposure after generation of nitrite via partial nitrification.
Mitigation of 3-deoxyglucosone and 5-hydroxymethylfurfural in brown fermented milk via an alternative browning process based on the hydrolysis of endogenous lactose
Authors: Han Zhonghui , Gao Jianxin , Li Jiaqi , Zhang Yan , Yang Yanan , Wang Shuo
Published: March 2019

An alternative browning process based on the hydrolysis of endogenous lactose instead of the external addition of glucose was established to mitigate the production of unhealthy Maillard reaction products.
Carbon nanoparticle template assisted formation of mesoporous TiO2 photoanodes for quantum dot-sensitized solar cells
Authors: Gao Qiqian , Wang Liying , Zhang Xueyu , Duan Lianfeng , Li Xuesong , Yang Xijia , Lü Wei
Published: March 2019

While the power conversion efficiency (PCE) of quantum dot-sensitized solar cells (QDSSCs) is still far below their theoretical efficiency, we herein provide a method to improve the solar cell performance by using carbon nanoparticles as a template to construct TiO2 mesoporous photoanodes.
High-quality perovskite films via post-annealing microwave treatment
Authors: Wang Kai-Li , Zhang Cong-Cong , Jiang Yu-Rong , Liu Hai-Rui , Li Xiao-Mei , Jain Sagar M. , Ma Heng
Published: March 2019

The crystalline quality of the perovskite film plays a key role in improving the optoelectronic properties and the performance of planar perovskite hybrid solar cells (PSCs).
Bridging the gap: 3D real-space characterization of colloidal assemblies via FIB-SEM tomography
Authors: van der Hoeven Jessi E. S. , van der Wee Ernest B. , de Winter D. A. Matthijs , Hermes Michiel , Liu Yang , Fokkema Jantina , Bransen Maarten , van Huis Marijn A. , Gerritsen Hans C. , de Jongh Petra E. , van Blaaderen Alfons
Published: March 2019

Focused ion beam-scanning electron microscopy tomography for quantitative real space studies of particle assemblies on a single particle level.
Significantly enhanced dielectric constant and energy storage properties in polyimide/reduced BaTiO3composite films with excellent thermal stability
Authors: Yue Shuangshuang , Wan Baoquan , Liu Yunying , Zhang Qiwei
Published: March 2019

The semiconductor properties of reduced barium titanate, with a high energy density of 9.7 J cm−3.
Iodine–DMSO-promoted divergent reactivities of arylacetylenes
Authors: Rather Suhail A. , Kumar Atul , Ahmed Qazi Naveed
Published: March 2019

An unprecedented set of efficient, economical, atom-economic and exceedingly selective I2–DMSO-promoted methods is described for the generation of different structures.
Distinct correlation between (CN2)x units and pores: a low-cost method for predesigned wide range control of micropore size of porous carbon
Authors: Feng Xiaotong , Bian Lei , Ma Jie , Zhou Lei , Wang Xiayan , Guo Guangsheng , Pu Qiaosheng
Published: March 2019

A low-cost method for predesigned wide range control of the micropore size of porous carbon by extendable (CN2)x units was confirmed.
An unprecedented hetero-bimetallic three-dimensional spin crossover coordination polymer based on the tetrahedral [Hg(SeCN)4]2−building block
Authors: Lan Wenlong , Valverde-Muñoz Francisco Javier , Hao Xiaoyun , Dou Yong , Muñoz M. Carmen , Zhou Zhen , Liu Hui , Liu Qingyun , Real José Antonio , Zhang Daopeng
Published: March 2019

A new non-Hoffmann type of hetero-bimetallic HgII–FeIIspin-crossover coordination polymer has been structurally and magnetically investigated.
Formation of homochiral helical nanostructures in diblock copolymers under the confinement of nanopores
Authors: Yang Tao , Xue Haiyan , Cao Ruifang , Li Weihua
Published: March 2019

The control of the homochirality of helical structures formed in achiral systems is of great interest as it is helpful for understanding the origin of homochirality in life.
Surface termination of MgB2 unveiled by a combination of adsorption experiments and theoretical calculations
Authors: Prudilová Barbora , Otyepková Eva , Fanfrlík Jindřich , Hnyk Drahomír , Holub Josef , Petr Martin , Filip Jan , Čépe Klára , Lazar Petr , Otyepka Michal
Published: March 2019

The importance of termination: the surface termination of MgB2 uncovered by combining inverse gas chromatography and theoretical calculations.
LIBS quantitative analysis for vanadium slags based on selective ensemble learning
Authors: Li Xiaomeng , Yang Jianhong , Chang Fu , Zheng Xiaomin , He Xiaoxia
Published: March 2019

Multi-elemental interference effect in LIBS quantitative analysis for vanadium slags is effectively solved by selective ensemble learning.
The regulatory effects of miR-138-5p on selenium deficiency-induced chondrocyte apoptosis are mediated by targeting SelM
Authors: Chi Qianru , Luan Yilin , Zhang Yiming , Hu Xueyuan , Li Shu
Published: March 2019

Apoptosis is a common paradigm of cell death and plays a key role in cartilage damage and selenium (Se) deficiency. Selenoproteins play major roles in determining the biological effects of Se, and are potentially involved in the pathophysiological processes in bone tissue. MicroRNAs (miRNAs) play important roles in cell proliferation, differentiation, apoptosis and tumorigenesis. Based on the preliminary results, the expression of selenoprotein M (SelM) was significantly decreased (69%) in chicken cartilage tissues with Se deficiency, and we subsequently screened and verified that SelM is one of the target genes of miR-138-5p in chicken cartilage using a dual luciferase reporter assay and real-time quantitative PCR (qRT-PCR). The expression of miR-138-5p was increased in response to Se deficiency, and the overexpression of miR-138-5p increased caspase-3, caspase-9, BAX and BAK levels, while the BCL-2 level was decreased, suggesting that miR-138-5p induced apoptosis via the mitochondrial pathway in vivo and in vitro. We explored whether oxidative stress, mitochondrial fission and fusion, and energy metabolism might trigger apoptosis to obtain an understanding of the mechanisms underlying the effects of miR-138-5p on Se deficiency-induced apoptosis in cartilage. The levels of indicators of oxidative stress, mitochondrial dynamics and energy metabolism were changed as well. This study confirmed that SelM is one of the target genes of miR-138-5p, and the overexpression of miR-138-5p induced by Se deficiency triggered oxidative stress, an imbalance in mitochondrial fission and fusion, and energy metabolism dysfunction. Therefore, miR-138-5p is involved in the mitochondrial apoptosis pathway via targeting SelM in chicken chondrocytes.
Size-matching hierarchical micropillar arrays for detecting circulating tumor cells in breast cancer patients’ whole blood
Authors: Wang Zhongshun , Xu Daren , Wang Xuekui , Jin Yue , Huo Bo , Wang Yalei , He Chengyan , Fu Xueqi , Lu Nan
Published: March 2019

A size-matching hierarchical micropillar array is fabricated for detecting circulating tumor cells in breast cancer patients’ whole blood.
Evolution of local conductance pathways in a single-molecule junction studied using the three-dimensional dynamic probe method
Authors: Taninaka Atsushi , Yoshida Shoji , Sugita Yoshihiro , Takeuchi Osamu , Shigekawa Hidemi
Published: March 2019

By combining a three-dimensional dynamic probe method with density functional theory, it has become possible to simultaneously consider the effect of the dynamics of molecular structures and the bonding states at the electrodes on the local transmission pathways and conductance.
Intramolecular dehydrogenative C–S bond coupling of thioamides to form 1,3-benzothiazines under metal-free conditions
Authors: Wen Li-Rong , Zhou Cheng-Cheng , Zhu Ming-Zhe , Xie Shu-Guang , Guo Wei-Si , Li Ming
Published: March 2019

A new protocol for the synthesis of 1,3-benzothiazines was developed through direct intramolecular dehydrogenative C–S bond coupling.
Aggregation-induced emission and polymorphism/shape/size-dependent emission behaviours of fenamates for potential drug evaluation
Authors: Wang Xinyi , Chen Yifu , Gong Junbo , Hou Jinze
Published: March 2019

Aggregation-induced emission and polymorphism/shape/size-dependent emission behaviors were found coexisting in fenamates, which provides a novel approach toward future drug evaluation.
Coordination–insertion polymerization of polar allylbenzene monomers
Authors: Hu Xiaoqiang , Ma Xin , Jian Zhongbao
Published: March 2019

Utilization of polar allylbenzene allows for a much enhanced activity (9–6300 times) of polar allyl monomers in the coordination–insertion copolymerization.
A computational study on ruthenium-catalyzed [4 + 1] annulation via C–H activation: the origin of selectivity and the role of the internal oxidizing group
Authors: Lian Bing , Zhang Lei , Fang De-Cai
Published: March 2019

Internal alkynes with β-H and hydroxyl groups lead to the [4 + 1] annulation.
Ultrahigh-surface-area nitrogen-doped hierarchically porous carbon materials derived from chitosan and betaine hydrochloride sustainable precursors for high-performance supercapacitors
Authors: Cheng Jian , Xu Qinqin , Wang Xia , Li Zaiquan , Wu Fuzhong , Shao Jiaojing , Xie Haibo
Published: March 2019

A biobased polyelectrolyte was prepared and used successfully as a precursor for the fabrication of N-doped hierarchically porous carbon materials with tunable electrochemical properties in supercapacitors.
An alternating nanoscale (hydrophilic–hydrophobic)/hydrophilic Janus cooperative copper mesh fabricated by a simple liquidus modification for efficient fog harvesting
Authors: Zhong Lieshuang , Feng Jing , Guo Zhiguang
Published: March 2019

Here, a comprehensive insight into a facile fabrication method for a (hydrophilic–hydrophobic)/hydrophilic Janus cooperative copper mesh was presented. The cooperation of alternating wettability and Janus membrane enhances the fog harvesting (∼800% enhancement).
Role of trivalent acceptors and pentavalent donors in colossal permittivity of titanium dioxide ceramics
Authors: Zhao Chunlin , Li Zhenwei , Wu Jiagang
Published: March 2019

We decode the role of trivalent acceptors and pentavalent donors on dielectric properties and defect structures in TiO2 CP ceramics.
Social–Cognitive and Speech Sound Production Abilities of Minimally Verbal Children With Autism Spectrum Disorders
Authors: Biller Maysoon F. , Johnson Cynthia J.
Published: March 2019

Purpose

To date, there has been a dearth of systematic research that examines both social–cognitive (SC) and speech sound production (SSP) abilities simultaneously in minimally verbal (MV) children with autism spectrum disorders (ASDs). Such an analysis would allow a unified and comprehensive view of the children's communication abilities. The purpose of this study was to develop detailed descriptive profiles of MV children with ASD and uncover patterns in their SC and SSP abilities that may pertain to spoken language.

Method

This study was a descriptive, multiple clinical case study that examined 5 MV children with ASD, 4 boys and 1 girl, aged 3–6 years. The case studies consisted of demographic information, parent report, and formal and informal assessment of the children. Four SC abilities and 3 SSP abilities were assessed.

Results

The 5 children's SC score, SSP score, and number of spoken words were converted to
z
scores. This analysis revealed 2 different patterns of development: 3 of the children had lower SC than SSP abilities, and 2 of the children had the reverse pattern.

Conclusions

The 5 children were low in both SC and SSP abilities. Although both domains were low, the measure that coincided most with spoken vocabulary among the 5 children was their SSP abilities. Specifically, the children had difficulty in demonstrating emerging control of the onset of voicing for specific speech sounds and verbal imitation of single speech sounds and syllables. Clinical implications of simultaneously assessing and treating SC and SSP abilities in MV children are discussed.
Evidence to Support Improved Outcomes for Older Adults From Dual-Task Training Through Interprofessional Collaboration
Authors: Milliken Lisa , Sullivan Neely
Published: March 2019

Purpose

By implementing a plan of care that can simulate dual-task activities carried out in daily life, is it possible to reduce or even avoid functional decline due to aging? Research has illustrated that cognition and executive functioning largely determines how independent someone can be as well as many aspects of their quality of life. Studies have shown that, as people age, cognition and executive functioning predicts one's chance of falling, ability to participate in meaningful life activities, and other aspects of function. One area of promise for interprofessional collaboration (between speech-language pathology, physical therapy, and occupational therapy) is that of dual-tasking to simultaneously target improved outcomes for older adults.

Method

A state-of-the-art review was conducted for research published on dual-task interventions for older adults from November 2012 through November 2017. Twelve research articles were reviewed and revealed evidence-based dual-task interventions for older adults that were positive for supporting interprofessional collaborative dual-task training for improved clinical outcomes.

Results and Conclusion

This research examined if dual-task training was recommended for an aging client population. The findings reinforced the need for additional research and adaptation of evidence-based dual-task training in therapy interventions.
Multi‐person pose estimation using atrous convolution
Authors: Lin Lu , Wang Yifei , Wang Lianghao , Zhang Ming , Li Dongxiao
Published: March 2019

The technology of human keypoint localisation has been greatly improved with the development of deep neural network. In particular, recent methods that exploit multi‐scale features and cascaded networks have achieved the accurate prediction of multi‐person keypoints. These methods typically extract small‐resolution feature maps with classical backbone and then generate heatmaps through upsampling. However, consecutive striding is harmful for keypoint localisation since detail information is decimated. In this Letter, the authors present a novel network structure that uses atrous spatial pyramid pooling to generate keypoint prediction. First, atrous convolution is used in the backbone to expand the receptive field and maintain the scale of the feature map. Thus, the size of the feature map can be guaranteed to avoid too many details being removed. Second, multi‐scale features are extracted using an atrous spatial pyramid pooling module to enrich the scale information of the obtained features. Finally, instead of upsampling, deconvolutional layers are applied to construct the output heatmaps. State‐of‐the‐art results are achieved on the MS COCO 2017 keypoint database.
Cooperative secrecy transmission in multi‐hop relay networks with interference alignment
Authors: Chen Zhuo , Hadley Lucinda , Ding Zhiguo , Dai Xuchu
Published: March 2019

In this study, the authors consider the secrecy communication of one source–destination pair in a wireless multi‐hop relay network, where each node is equipped with multiple antennas. They use the method of interference alignment for secrecy transmission in the presence of an eavesdropper. Firstly, they propose a decode‐and‐forward (DF) relaying protocol and give a new result on the joint probability density function of the first, second, …, kth () largest eigenvalues of the complex Wishart matrices , where is an matrix whose elements are independent identically distributed complex Gaussian variables with zero mean and unit variance. They then utilise this result to characterise the legitimate outage probability and the diversity order of the proposed DF protocol. The case where the relay works in the amplify‐and‐forward (AF) mode is considered at last, and the diversity order of the proposed AF protocol is given.
Using multi‐address generation and duplicate address detection to prevent DoS in IPv6
Authors: Guangjia Song , Hui Wang , Hangjun Wang
Published: March 2019

The Neighbour Discovery Protocol and the Address Resolution Protocol are important protocols in the data link layer. Their functions include Internet Protocol (IP) address configuration, resolving the correspondence between an IP address and a medium access control address, and duplicate address detection (DAD). In DAD, the new address that the node is going to use is public, and thus, it is vulnerable to malicious node attacks. Moreover, address configuration is inefficient because only one address is generated and detected each time. In this study, the authors propose a multi‐address generation and DAD scheme called MAGD. MAGD generates a set of addresses each time, but only discloses a part of the set during DAD, thereby reducing the risk of being attacked. DAD will only fail when all the addresses are in conflict, and thus, the efficiency of node's address configuration is enhanced. Experiments show that the additional overhead in the CPU and memory caused by MAGD's multiple address configuration is within an acceptable range. When subjected to denial‐of‐service (DoS) attacks, MAGD performs better than traditional encryption schemes.
Cross‐layer design of resource allocation and segment adaptation based on CPIQ model for DASH clients over LTE networks
Authors: Yang Jin , Qiao Ruiping , Ma Ruijie , Li Fan
Published: March 2019

With the rapid development of dynamic adaptive streaming over HTTP (DASH) services, how to satisfy the requirements of DASH clients has attracted more and more attention. This study was carried out to focus on the quality of experience (QoE) modelling and the model‐based cross‐layer design which consists of segment adaptation and resource allocation, improving the playback experience of the clients. First, the key factors are investigated, which can affect the clients’ subjective satisfaction. A characteristics and playback information of the segments‐based QoE (CPIQ) model is established by employing the curve‐fitting method based on a large amount of subjective experimental results of these factors. Then with the CPIQ model as the objective function, a cross‐layer design CPIQ model‐based joint algorithm of segment request and resource allocation (CJRRA) model is formulated to maximise the total QoE of all the clients subject to the network resource and segment representation constraints. Segment adaptation and resource allocation strategy can be determined jointly by the authors developed low complexity solution. Finally, the simulation results show that the overall performance of CPIQ model and CJRRA significantly outperforms other compared models or algorithms in terms of accuracy, linearity and stability.
Determination of transformer HV winding axial displacement extent using hyperbolic method – a feasibility study
Authors: Rahbarimagham Hesam , Karami Hossein , Esmaeili Saeid , Gharehpetian Gevork B.
Published: March 2019

In recent years, ultra‐wideband (UWB) systems have been proposed for online monitoring of power transformers. This study aims at a new UWB‐based method to determine the axial displacement (AD) extent in the transformer high‐voltage (HV) winding. In the proposed design, two receiving antennas and one transmitting antenna are used. Two receiving antennas receive signals at two different positions due to axial displacement occurrence, and the displacement extent is determined using an analytical method known as hyperbolic method, which is based on signals time difference of arrival. The proposed method is initially studied by simulations using computer simulation technology software. Finally, the experimental results show the effectiveness of the proposed method to detect the AD extent in an actual transformer winding.
Deep learning‐based vehicle detection with synthetic image data
Authors: Wang Ye , Deng Weiwen , Liu Zhenyi , Wang Jinsong
Published: March 2019

Deep convolutional neural network (CNN)‐based object detectors perform better than other kinds of object detectors in recent development. Training CNNs needs large amounts of annotated data. The acquisition and annotation of real images are arduous and often lead to inaccuracy. In order to solve this problem, the authors try to use synthetic images as substitute to train a vehicle detector. Annotation on synthetic images can be performed automatically, and can obtain better uniformity. Furthermore, it is also easy to get more variations in synthetic images. The authors present a pipeline to generate synthetic images for training vehicle detector. In this pipeline, many factors are considered to add more variations and extend the domain of training dataset. Thus, the detector trained with synthetic images is expected to perform well. The extent to which these factors influence detection performance is illustrated. However, the performance of a vehicle detector trained with synthetic images is not as good as that with real images because of domain gap. In this study, the authors develop a transfer learning approach to improve the performance of authors' vehicle detector with only a few manually annotated real images.
Rollover risk assessment and automated control for heavy duty vehicles based on vehicle‐to‐infrastructure information
Authors: He Yi , Yan Xinping , Lu Xiao‐Yun , Chu Duanfeng , Wu Chaozhong
Published: March 2019

A novel rollover risk assessment and control approach is presented. First, a road‐vehicle‐environment coupling model with various random parameters, including wind velocity and road curvature, is developed. Second, a safety margin is defined to divide the safe and dangerous domains in the parameter space. Then, the first‐order reliability method (FORM) approximation is developed to evaluate the probability of rollover accidents using a vehicle dynamics model. Finally, the state‐space equation of automated control system is built based on model prediction control (MPC). With the front wheel steering angle and four wheels' braking torque as the control inputs, the additional yaw moment is used to prevent vehicle rollover. The control system model is implemented on the Trucksim/Simulink simulation platform. The results show that the automated control system proposed can prevent vehicle rollover effectively and enhance the driving performance of the vehicle. This study suggests that the presented rollover risk assessment and control methodologies can effectively estimate the rollover risk for HDVs under complex environments, whereas doing so would be very difficult with sensors alone.
Design of mechanically rotatable microstrip patch antennas using an asymmetric polariser for adaptive polarisation adjustment
Authors: Yoo Sungjun , Choo Hosung , Byun Gangil
Published: March 2019

This paper proposes the design of a microstrip patch antenna with an asymmetric polariser for adaptive polarisation adjustment. The asymmetric polariser is placed in the outer perimeter of a circular radiating patch and is mechanically rotated from 0° to 360° to adjust the axial ratio (AR) and the tilt angle (TA). To verify the operating principle of the proposed antenna, its radiating properties are theoretically formulated based on the cavity model, and three sample antennas with different shapes of the polariser are fabricated to measure their antenna characteristics. Then, a field test is conducted to observe variations of the received signal strength for incoming signals with time‐varying polarisation properties. The results demonstrate that the mechanical rotation of the polariser is suitable to minimise the polarisation mismatch with improvement of the received signal strength from −44.0 to −30.3 dBm in a harsh multipath environment.
Beam‐scanning leaky‐wave antenna based on CRLH‐metamaterial for millimetre‐wave applications
Authors: Alibakhshikenari Mohammad , Virdee Bal S. , Khalily Mohsen , Shukla Panchamkumar , See Chan H. , Abd‐Alhameed Raed , Falcone Francisco , Limiti Ernesto
Published: March 2019

This paper presents empirical results of an innovative beam‐scanning leaky‐wave antenna (LWA), which enables scanning over a wide angle from − 35° to + 34.5° between 57 and 62 GHz, with broadside radiation centred at 60 GHz. The proposed LWA design is based on composite right/left‐handed transmission‐line (CRLH‐TL) concept. The single‐layer antenna structure includes a matrix of 3 × 9 square slots that is printed on top of the dielectric substrate; and printed on the bottom ground‐plane are Π‐ and T‐shaped slots that enhance the impedance bandwidth and radiation properties of the antenna. The proposed antenna structure exhibits metamaterial property. The slot matrix provides beam scanning as a function of frequency. Physical and electrical size of the antenna is 18.7 × 6 × 1.6 mm3 and 3.43  × 1.1  × 0.29, respectively, where is free space wavelength at 55 GHz. The antenna has a measured impedance bandwidth of 10 GHz (55–65 GHz) or fractional bandwidth of 16.7%. Its optimum gain and efficiency are 7.8 dBi and 84.2% at 62 GHz.
Random forests‐enabled context detections for long‐term evolution network forrailway
Authors: Zhang Lei , Ni Qin , Zhang Guanglin , Zhai Menglin , Moreno Juan , Briso Cesar
Published: March 2019

An ensemble learning‐based approach for context detection for high‐speed railway (HSR) isproposed, evaluated, and compared against various machine learning algorithms.The context information is collected and formatted from the realistic physicaldata, which are measured by the field test in a commercial 4G cellular networkon‐board high‐speed train in an open area, HSR station, and typical urban area.The radio propagation knowledge implies that the channel model is implemented infeature extractions. The independent out‐of‐bag errors show ensemble learningapproaches; especially, random forests‐based algorithm achieves very accuratecontext detection (up to 93.5%), which is much higher than single tree (66%).Other ensembles with sub‐spaces of discriminant (67%) and K‐nearest neighbour(69%), as well as linear discriminant analysis (55.7%), and support vectormachine (SVM) (27.7%). Furthermore, the features are selected based on thefeature importance evaluation in the first round training. The selectedpredominant features and the reasonable number of individual trees construct therefined random forests, which obtain a high accuracy (92.6%) and 70% timereducing. This experimental study benefits from physical radio knowledge tosupport advanced long‐term evolution (LTE) network for railway and future smartrail applications.
Investigation of sparse near‐field focusing array antenna with different topologies
Authors: Yang Xiao Lin , Cheng Yu Jian
Published: March 2019

The method to efficiently design a sparse near‐field focusing sparse array antenna is introduced here. First, the calculation model and analysis method of three array topologies including the square grid, the circular grid, and the regular triangular grid are established. The evaluation criterion is the lowest sparsity under the condition that the focusing performance of the sparse array approaches to that of a referenced focusing array with the element spacing of a half of one wavelength. After comparing the focusing performance of these array antennas with different grids, the circular‐grid array is the optimal one and selected to further discuss the influence of different topology parameters. The optimal sparse near‐field focusing array should have the constant distance between two adjacent rings and increase three elements compared with the last ring. Finally, the method based on the proposed selection criteria is employed to design a sparse near‐field focusing sparse array. The correctness of the method has been validated by the full‐wave simulated results.
Compact dual‐band filter using interleaved folded half‐mode substrate integrated waveguide resonator
Authors: Guo Jun , You Bin , Zhang Xiao Hong , Luo Guo Qing
Published: March 2019

A multi‐layer interleaved folded half‐mode substrate integrated waveguide (HMSIW) dual‐band filter is proposed. The TE101 and TE102 mode of the HMSIW resonators form dual‐band response by vertical coupling, and the bandwidth of the two passbands can be independently designed by adjusting the coupling apertures. Moreover, three transmission zeros (TZs) are obtained to improve out‐of‐band rejection, and the TZs can be flexibly designed below or above the passband. By vertically superimposing the HMSIW cavity, the HMSIW filter can be extended to multi‐pole dual‐band filters. A dual‐band filter with centre frequency of 3.05 and 4.7 GHz was fabricated and measured to verify the proposed method. The simulated and measured results are in good agreement.
Investigation on conducted EMI noise source impedance extraction for electro magnetic compatibility based on SP‐GA algorithm
Authors: Mengxia Zhou , Yang Zhao , Wei Yan , Yi Cao , Moeed Abdul , Yinsen Jia , Xi Wang
Published: March 2019

A new approach employing scattering parameters (SPs) and genetic algorithm (GA) (SP‐GA) is proposed for modelling conducted electromagnetic interference (EMI) noise source impedance. Based on the principle of SPs, the source impedance is measured through transmission and reflection parameters from a vector network analyser when the circuit is shorted and loaded with noise source impedance, respectively. Moreover, amplitude‐frequency performance and phase‐frequency performance are optimised by using GA, and therefore the equivalent resistance, capacitance, and inductance are attained following the usual formula of the phase and amplitude of source impedance. This work made contribution for the design of the conducted EMI filter.
Wireless power transfer based on current non‐linear PT‐symmetry principle
Authors: Dong Wenjie , Li Changsheng , Zhang He , Ding Libo
Published: March 2019

In this study, the authors propose a novel circuit topology based on the current non‐linear parity‐time (PT)‐symmetry principle. The exact analytical solutions of transfer efficiency and resonant frequency are deduced, a state switching phenomenon is observed, and the mathematical expression of the critical coupling coefficient (κc) corresponding to the state switching point is provided. When the coupling coefficient (κ) is ≥κc, the system has two real frequencies and can maintain near 100% transfer efficiency theoretically. When κ < κc, the system has only one real frequency, and the transfer efficiency attenuates rapidly. The correctness of the theoretical model is verified by simulation and experiment. Results show that when the distance between the two coils (38 cm in diameter) varies from 10 to 42.5 cm, the transfer efficiency remains ∼95%, without the need for any tuning. Theoretical analysis and experimental verification show that κc increases when the load resistance increases and the natural resonant frequency or the self‐inductance of the Rx coil decreases. Furthermore, the system can maintain the equivalent current of the Tx and Rx circuits when κ ≥ κc, which is convenient for controlling the circuit current, and suitable for the case of small load and large current.
Heuristic optimisation‐based sizing and siting of DGs for enhancing resiliency of autonomous microgrid networks
Authors: Hussain Akhtar , Shah Syed Danial Ali , Arif Syed Muhammad
Published: March 2019

A power distribution network is a critical infrastructure in any society and any disruption has an enormous impact on the economy and daily lives. Therefore, the objective of this study is to transform the conventional power distribution systems into resilient autonomous microgrid networks by optimally sizing and siting the distributed generators (DGs). First, N main DGs are placed to transform an existing network into an autonomous microgrid network. Second, all the possible combinations of the initially deployed DGs are made and then the outage of 1 to N  − 1 DGs is considered. Considering the outage of DGs in each combination (one at a time), the resiliency of the network is analysed. Amount of load shedding, total power loss in the network, and voltage limits are analysed in this step. Finally, based on the resiliency analysis, additional DGs are placed to enhance the resiliency of the transformed network. Heuristic methods (particle swarm optimisation and genetic algorithm) are used for both sizing and siting of DGs during the first and the second steps. The objective of the formulation is to minimise load shedding, total power loss (active and reactive), and voltage deviations in the network during DG outages.
CO, H2O, H2O+ line and dust emission in a z = 3.63 strongly lensed starburst merger at sub-kiloparsec scales
Authors: Yang C. , Gavazzi R. , Beelen A. , Cox P. , Omont A. , Lehnert M. D. , Gao Y. , Ivison R. J. , Swinbank A. M. , Barcos-Muñoz L. , Neri R. , Cooray A. , Dye S. , Eales S. , Fu H. , González-Alfonso E. , Ibar E. , Michałowski M. J. , Nayyeri H. , Negrello M. , Nightingale J. , Pérez-Fournon I. , Riechers D. A. , Smail I. , van der Werf P.
Published: March 2019

Using the Atacama Large Millimeter/submillimeter Array (ALMA), we report high angular-resolution observations of the redshift z  = 3.63 galaxy H-ATLAS J083051.0+013224 (G09v1.97), one of the most luminous strongly lensed galaxies discovered by the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS). We present 0.″2−0.″4 resolution images of the rest-frame 188 and 419 μm dust continuum and the CO(6–5), H2O(211−202), and Jup = 2 H2O+ line emission. We also report the detection of H2O(211−202) in this source. The dust continuum and molecular gas emission are resolved into a nearly complete ∼1.″5 diameter Einstein ring plus a weaker image in the center, which is caused by a special dual deflector lensing configuration. The observed line profiles of the CO(6–5), H2O(211−202), and Jup = 2 H2O+ lines are strikingly similar. In the source plane, we reconstruct the dust continuum images and the spectral cubes of the CO, H2O, and H2O+ line emission at sub-kiloparsec scales. The reconstructed dust emission in the source plane is dominated by a compact disk with an effective radius of 0.7 ± 0.1 kpc plus an overlapping extended disk with a radius twice as large. While the average magnification for the dust continuum is μ ∼ 10−11, the magnification of the line emission varies from 5 to 22 across different velocity components. The line emission of CO(6–5), H2O(211−202), and H2O+ have similar spatial and kinematic distributions. The molecular gas and dust content reveal that G09v1.97 is a gas-rich major merger in its pre-coalescence phase, with a total molecular gas mass of ∼1011 M⊙. Both of the merging companions are intrinsically ultra-luminous infrared galaxies (ULIRGs) with infrared luminosities LIR reaching ≳4 × 1012 L⊙, and the total LIR of G09v1.97 is (1.4 ± 0.7)×1013 L⊙. The approaching southern galaxy (dominating from V = −400 to −150 km s−1 relative to the systemic velocity) shows no obvious kinematic structure with a semi-major half-light radius of as = 0.4 kpc, while the receding galaxy (0 to 350 km s−1) resembles an as = 1.2 kpc rotating disk. The two galaxies are separated by a projected distance of 1.3 kpc, bridged by weak line emission (−150 to 0 km s−1) that is co-spatially located with the cold dust emission peak, suggesting a large amount of cold interstellar medium (ISM) in the interacting region. As one of the most luminous star-forming dusty high-redshift galaxies, G09v1.97 is an exceptional source for understanding the ISM in gas-rich starbursting major merging systems at high redshift.
Dense gas is not enough: environmental variations in the star formation efficiency of dense molecular gas at 100 pc scales in M 51
Authors: Querejeta M. , Schinnerer E. , Schruba A. , Murphy E. , Meidt S. , Usero A. , Leroy A. K. , Pety J. , Bigiel F. , Chevance M. , Faesi C. M. , Gallagher M. , García-Burillo S. , Glover S. C. O. , Hygate A. P. S. , Jiménez-Donaire M. J. , Kruijssen J. M. D. , Momjian E. , Rosolowsky E. , Utomo D.
Published: March 2019

It remains unclear what sets the efficiency with which molecular gas transforms into stars. Here we present a new VLA map of the spiral galaxy M 51 in 33 GHz radio continuum, an extinction-free tracer of star formation, at 3″ scales (∼100 pc). We combined this map with interferometric PdBI/NOEMA observations of CO(1–0) and HCN(1–0) at matched resolution for three regions in M 51 (central molecular ring, northern and southern spiral arm segments). While our measurements roughly fall on the well-known correlation between total infrared and HCN luminosity, bridging the gap between Galactic and extragalactic observations, we find systematic offsets from that relation for different dynamical environments probed in M 51; for example, the southern arm segment is more quiescent due to low star formation efficiency (SFE) of the dense gas, despite its high dense gas fraction. Combining our results with measurements from the literature at 100 pc scales, we find that the SFE of the dense gas and the dense gas fraction anti-correlate and correlate, respectively, with the local stellar mass surface density. This is consistent with previous kpc-scale studies. In addition, we find a significant anti-correlation between the SFE and velocity dispersion of the dense gas. Finally, we confirm that a correlation also holds between star formation rate surface density and the dense gas fraction, but it is not stronger than the correlation with dense gas surface density. Our results are hard to reconcile with models relying on a universal gas density threshold for star formation and suggest that turbulence and galactic dynamics play a major role in setting how efficiently dense gas converts into stars.
Antiduality and Möbius monotonicity: generalized coupon collector problem
Authors: Lorek Paweł
Published: March 2019

For a given absorbing Markov chain X* on a finite state space, a chain X is a sharp antidual of X* if the fastest strong stationary time (FSST) of X is equal, in distribution, to the absorption time of X*. In this paper, we show a systematic way of finding such an antidual based on some partial ordering of the state space. We use a theory of strong stationary duality developed recently for Möbius monotone Markov chains. We give several sharp antidual chains for Markov chain corresponding to a generalized coupon collector problem. As a consequence – utilizing known results on the limiting distribution of the absorption time – we indicate separation cutoffs (with their window sizes) in several chains. We also present a chain which (under some conditions) has a prescribed stationary distribution and its FSST is distributed as a prescribed mixture of sums of geometric random variables.
Framing effects on public support for carbon capture and storage
Authors: Whitmarsh Lorraine , Xenias Dimitrios , Jones Christopher R.
Published: March 2019

Carbon Capture and Storage (CCS) involves trapping carbon dioxide (CO2) from power generation and heavy industrial processes and directing it into long-term geological storage (e.g., in depleted oil fields or saline aquifers). In doing so, CCS could facilitate global carbon abatement efforts. Yet, it remains controversial with high-profile public opposition to particular CCS developments. For instrumental, normative and substantive reasons, it is increasingly recognised that public acceptance of CCS as a vital precondition for its commercial-scale rollout. While much is known about factors influencing public support for CCS, relatively few cross-national studies have so far been undertaken. Here, we present findings from a large-scale international experimental study of public perceptions of CCS, to examine how individual, geographical and informational factors influence support for CCS. In particular, we compare the lens through which CCS is seen – as a ‘techno-fix’ climate change solution, as reusing a waste product (through Carbon Dioxide Utilisation [CDU]), or as part of a systemic approach to climate change mitigation. Pairing CCS with CDU led to higher support for CCS, although information frames interacted with national and individual-level factors. Depending on which CCS lens is chosen, different groups will be more or less likely to support CCS implementation. As with other issues, targeting CCS information to audience values is likely to be more effective than untargeted communication. Our findings also show mentioning (modest) costs of deploying CCS can lead to lower support. Discussing CCS costs should be done in the context of costs of broader energy system transformation and of not mitigating climate change so that the public can deliberate over the relative risks and benefits of CCS and alternatives in the context of broader sustainability pathways.
Subnational politics of the urban age: evidence from Brazil on integrating global climate goals in the municipal agenda
Authors: de Macedo Laura Silvia Valente , Jacobi Pedro Roberto
Published: March 2019

As nations agreed on a bottom-up approach to establish the Paris Agreement in 2015, Non-state Actors (NSAs) became increasingly acknowledged as key players in the implementation of Nationally Determined Contributions (NDCs). In a mostly urbanised world, local governments have a major part to play in designing and implementing climate policies that will help overcome carbon lock-in and enable the transition to a sustainable low-carbon future. Transnational municipal networks (TMNs) have a well-documented history of contributing to multilevel climate governance and supporting experiments in local climate action in many countries. In Brazil, urban climate experimentation has increased since 2005 and accelerated after 2015. Based on empirical evidence from a national survey and two Brazilian metropolises, the study demonstrates that TMNs have been drivers of the municipal climate agenda in Brazil, but there is no evidence so far that urban governance experiments have resulted in significant greenhouse gas emission reductions. Furthermore, the collective impact of cities' experimentation on the national climate agenda is yet to be verified. In light of multilevel climate governance and the urban experimentation conceptual framework, we contend that while there is no documented evidence that local climate action has affected Brazil's ability to meet its mitigation goals, cities' paradiplomacy and policy experiments have strengthened a multilevel approach to climate governance and contributed to positive change towards a sustainable transition. Furthermore, a closer look at policies across scales and their interactions will help our understanding of how to improve t'he institutional framework for climate governance in Brazil and secure GHG emission reductions, thus contributing to global goals beyond 2020.
Study of attenuation characteristics of electromagnetic waves in multilayer plasma slabs
Authors: Zhang Qingchao , Tian Zengyao , Tang Wenyuan , Tang Nian , Zhao Hu , Lin Hui
Published: March 2019

Stealth technology plays an important role in modern military conflicts, and because of its many practical advantages, plasma stealth technology has gained a lot of attention. In this paper, we describe our study of the reflection and absorption characteristics of waves propagating in multilayer plasma slabs. Our results show that positive effects on the attenuation can be obtained by optimizing the plasma parameters and by increasing the number of plasma layers. We also found that multilayer plasma slabs can effectively widen absorption bands, especially for low frequency bands.
Evidence of within-species specialization by soil microbes and the implications for plant community diversity
Authors: Eck Jenalle L. , Stump Simon M. , Delavaux Camille S. , Mangan Scott A. , Comita Liza S.
Published: March 2019

Significance

It is widely known from agriculture that pathogens can specialize on genotypes within plant species, but such highly specialized pathogens have rarely been studied in natural plant communities. Although empirical evidence in natural plant communities demonstrates that pathogens can specialize at the level of species, our experiment in Panama demonstrates specialization of soil microbes within a wild plant population. Our complementary computer simulations suggest that genotype-level specialization by microbes may help maintain plant species diversity and promote the evolution of increased seed dispersal. Together, our results improve understanding of the role of microbes in natural plant communities by showing that microbes that specialize within species could influence diversity and dynamics in plant communities.
Reframing the linguistic to analyze the landscape
Authors: Michalovich Amir
Published: March 2019

This article examines how eliciting metaphors from multimodal commercials can facilitate a critical interpretation of advertising media, which is ubiquitous in the LL and highly manipulative. Adolescent students, a population which is particularly vulnerable to advertising’s influence, utilized the analytic tool of metaphor elicitation to abstract away from the vast multimodal information that characterizes commercials, and simplify this information in the linguistic formulation of metaphor (e.g., super-pharm is a circus). The contrived link between the given brand (e.g., Super-Pharm pharmaceutical stores) and its metaphorically-attached source domain (e.g., circus) was emphasized to increase awareness of how the commercial was structured to deceive consumers. The study evaluated the intervention using a quasi-experimental design, showing that metaphor elicitation facilitated the knowledge, critical attitudes, and responsible behavioral inclinations of participants concerning advertising media. The study suggests that using the linguistic formulation of metaphor can help adolescents critically interpret the increasingly-deceptive commercial landscape.
Using experimental approaches to study translation
Authors: Hatzidaki Anna
Published: March 2019

In the last few years, the study of the cognitive processes that underlie the translating act is well under way in
the field of translation studies (TS). Yet considering the potential of this research area, translation behaviour and how it is
affected and modulated by linguistic and psycholinguistic factors is still underinvestigated. The main culprit of this holdback
appears to be fuzziness over what experimental methods are expected to deliver and how sometimes
they are actually used. The present discussion article outlines these aspects, draws attention to methodological issues commonly
encountered when an experimental approach is adopted, and suggests ways to overcome the challenges posed by this promising line of
research.