bluuebunny/crossref_metadata_2025 huggingface dataset:
Is It the Investment Bank or the Investment Banker? A Study of the Role of Investment Banker Human Capital in Acquisitions
Authors: Chemmanur Thomas J. , Ertugrul Mine , Krishnan Karthik
Published: September 2018

Using a novel data set that links individual investment bankers to the acquisition deals they advise on, we find that individual investment bankers with greater deal experience are associated with higher acquisition returns and post-acquisition operating performance, particularly for acquirers in complex and more opaque industries. The advisory fee on acquisitions is also positively associated with the investment banking team’s experience. Finally, when more experienced investment bankers switch to a new bank, acquirers are more likely to move with them. Overall, our results suggest that the human capital of individual investment bankers is valuable to acquirers.
Genetic and environmental contribution to the overlap between ADHD and ASD trait dimensions in young adults: a twin study
Authors: Ghirardi Laura , Pettersson Erik , Taylor Mark J. , Freitag Christine M. , Franke Barbara , Asherson Philip , Larsson Henrik , Kuja-Halkola Ralf
Published: September 2018

Background

Traits of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are strongly associated in children and adolescents, largely due to genetic factors. Less is known about the phenotypic and aetiological overlap between ADHD and ASD traits in adults.

Methods

We studied 6866 individuals aged 20–28 years from the Swedish Study of Young Adult Twins. Inattention (IA) and hyperactivity/impulsivity (HI) were assessed using the WHO Adult ADHD Self-Report Scale-V1.1. Repetitive and restricted behaviours (RRB) and social interaction and communication (SIC) were assessed using the Autism-Tics, ADHD, and other Comorbidities inventory. We used structural equation modelling to decompose covariance between these ADHD and ASD trait dimensions into genetic and shared/non-shared environmental components.

Results

At the phenotypic level, IA was similarly correlated with RRB (r= 0.33; 95% Confidence Interval (CI) 0.31–0.36) and with SIC (r= 0.32; 95% CI 0.29–0.34), whereas HI was more strongly associated with RRB (r= 0.38; 95% CI 0.35–0.40) than with SIC (r= 0.24; 95% CI 0.21–0.26). Genetic and non-shared environmental effects accounted for similar proportions of the phenotypic correlations, whereas shared environmental effects were of minimal importance. The highest genetic correlation was between HI and RRB (r= 0.56; 95% 0.46–0.65), and the lowest was between HI and SIC (r= 0.33; 95% CI 0.23–0.43).

Conclusions

We found evidence for dimension-specific phenotypic and aetiological overlap between ADHD and ASD traits in adults. Future studies investigating mechanisms underlying comorbidity between ADHD and ASD may benefit from exploring several symptom-dimensions, rather than considering only broad diagnostic categories.
Sun behaviour and physical activity associated with autumn vitamin D status in 4–8-year-old Danish children
Authors: Mortensen Charlotte , Mølgaard Christian , Hauger Hanne , Kristensen Michael , Damsgaard Camilla T
Published: September 2018

Objective

To explore determinants of serum 25-hydroxyvitamin D (s-25(OH)D) during autumn in young, Caucasian children not consuming vitamin D-fortified foods or supplements, and explore differences in sun behaviours between pre-school and school children.

Design

In September–October, s-25(OH)D was measured by LC–MS/MS; physical activity, sun behaviours and vitamin D intake were assessed with questionnaires.

Setting

Baseline data from the ODIN Junior trial at 55°N.

Subjects

Children aged 4–8 years (n130), of whom 96% gave blood samples.

Results

Mean s-25(OH)D was 56·8 (sd12·5) nmol/l and positively associated with fat-free mass index (P=0·014). Children being active 6–7 h/week had 5·6 (95% CI 1·1, 10·0) nmol/l higher s-25(OH)D than less active children (P=0·014). Children seeking shade sometimes or rarely/never had 7·0 (95% CI 1·2, 12·9;P=0·018) and 7·2 (95% CI 0·8, 13·6;P=0·028) nmol/l higher s-25(OH)D, respectively, than children always/often seeking shade. Pre-school children had more sun-safe behaviour than school children in terms of use of a hat, sunscreen and sunscreen sun protection factor (P<0·05). In school but not pre-school children, using a hat rarely/never was associated with 12·1 (95% CI 2·5, 21·7;P=0·014) nmol/l higher s-25(OH)Dv. always/often (Pinteraction=0·019). Vitamin D intake was not associated with s-25(OH)D (P=0·241).

Conclusions

Physical activity and sun behaviours are associated with s-25(OH)D in young children. Identifying factors influencing autumn s-25(OH)D is relevant to optimize levels before sun exposure diminishes. Strategies to reduce risk of inadequacy should consider risk of skin cancer and sunburn, and could include fortification and/or vitamin D supplementation.
Differential Response of Arkansas Palmer Amaranth (Amaranthus palmeri) to Glyphosate and Mesotrione
Authors: Singh Shilpa , Roma-Burgos Nilda , Singh Vijay , Alcober Ed Allan L. , Salas-Perez Reiofeli , Shivrain Vinod
Published: September 2018

We conducted a greenhouse study to evaluate the differential response of Palmer amaranth to glyphosate and mesotrione and to quantify the level of tolerance to mesotrione in recalcitrant (difficult-to-control) accessions and their offspring. Seeds were collected from 174 crop fields (corn, cotton, and soybean) across Arkansas between 2008 and 2016. Palmer amaranth seedlings (7 to 10 cm tall) were treated with glyphosate at 840 g ae ha–1or mesotrione at 105 g ha–1. Overall, 47% of the accessions (172) were resistant to glyphosate with 68% survivors. Almost 35% of accessions were highly resistant, with 90% survivors. The majority of survivors from glyphosate application incurred between 31% and 60% injury. Mesotrione killed 66% of the accessions (174); the remaining accessions had survivors with injury ranging from 61% to 90%. Accessions with the least response to mesotrione were selected to determine tolerance level. Dose–response assays were conducted with four recalcitrant populations and their F1progeny. The average effective doses (ED50) for the parent accessions and F1progeny of survivors were 21.5 g ha–1and 27.5 g ha–1, respectively. The recalcitrant parent populations were three- to five-fold more tolerant to mesotrione than the known susceptible population, as were the F1progeny.
Der Einfluss von Resilienz auf qualitative Formen der Arbeitszufriedenheit
Authors: Schlett Christian , Pauls Nina , Soucek Roman
Published: September 2018

Zusammenfassung. Das Arbeitszufriedenheitsmodell von Bruggemann (1974) unterscheidet qualitative Arbeitszufriedenheitsformen (AZ-Formen), die sich auf das Befinden bei der Arbeit auswirken. Obwohl diese AZ-Formen auf individuellen Verarbeitungsprozessen basieren, wurden deren personenbezogene Einflussfaktoren bisher nur selten untersucht. Die vorliegende Arbeit überprüft diesbezüglich den Einfluss der individuellen Resilienz auf die AZ-Formen und untersucht deren Auswirkungen auf das Befinden bei der Arbeit. Hierzu wurden drei Studien mit insgesamt 477 Beschäftigten in drei Unternehmen durchgeführt. Außer den AZ-Formen wurden in diesen Studien die Arbeitsbelastung, personale Ressourcen der Resilienz (Selbstwirksamkeit, Optimismus und Achtsamkeit), resilientes Verhalten bei der Arbeit, Arbeitsengagement und psychische Befindensbeeinträchtigungen erfasst. Die Ergebnisse verdeutlichen die Bedeutsamkeit der Resilienz für die qualitative Form der Arbeitszufriedenheit und bieten Ansatzpunkte, wie AZ-Formen, die mit Befindensbeeinträchtigungen einhergehen, begegnet werden kann.
Flexural Analysis Along the Sunda Trench: Bending, Buckling and Plate Coupling
Authors: Raghuram G. , Capitanio Fabio A. , Radhakrishna M.
Published: September 2018

The bathymetry and free‐air gravity data offshore Sunda trench are used here to analyze the flexural forebulge and bending moment variations along the Southeast Asian subduction zone. The observed bathymetry is corrected for various effects such as the sediment loading, lithosphere age, and the gravity‐derived isostatically compensated topography, which gave rise to the flexural deformation surface of the subducting Indo‐Australian plate. From this, 28 across‐trench sections were constructed to model the plate flexural bending along the Sunda trench. We observed that except in the northern Sumatra trench, rest of the Sunda trench is in agreement with the flexural model explained by the bending moment applied by the slab. In the northern Sumatra part of the trench, additional horizontal stresses of ~30–40 MPa are required for better match of the flexural forebulge thereby increasing the coupling with the upper plate. The outcome of this analysis in comparison with the slab depth variation, which abruptly reduces from ~600 km in Java to ~200 km toward northern Sumatra, suggests that very large bending moment and horizontal stresses are anticorrelated with the slab depth. The shorter slab in Sumatra does not effectively pull the incoming plate in the mantle, and therefore, plate convergence is accommodated at shallow depth, increasing the coupling with the upper plate. We propose that horizontal stresses are the result of the lateral propagation of the stronger slab pull from the neighboring deeper southeastern Java slab.
Structural characterization of a novel KH-domain containing plant chloroplast endonuclease
Authors: Rout Ashok K. , Singh Himanshu , Patel Sunita , Raghvan Vandana , Gautam Saurabh , Minda R. , Rao Basuthkar J. , Chary Kandala V. R.
Published: September 2018

Chlamydomonas reinhardtiiis a single celled alga that undergoes apoptosis in response to UV-C irradiation. UVI31+, a novel UV-inducible DNA endonuclease inC.reinhardtii, which normally localizes near cell wall and pyrenoid regions, gets redistributed into punctate foci within the whole chloroplast, away from the pyrenoid, upon UV-stress. Solution NMR structure of the first putative UV inducible endonuclease UVI31+ revealed an α1–β1–β2–α2–α3–β3fold similar to BolA and type II KH-domain ubiquitous protein families. Three α−helices of UVI31+ constitute one side of the protein surface, which are packed to the other side, made of three-stranded β–sheet, with intervening hydrophobic residues. A twenty-three residues long polypeptide stretch (D54-H76) connecting β1and β2strands is found to be highly flexible. Interestingly, UVI31+ recognizes the DNA primarily through its β–sheet. We propose that the catalytic triad residues involving Ser114, His95 and Thr116 facilitate DNA endonuclease activity of UVI31+. Further, decreased endonuclease activity of the S114A mutant is consistent with the direct participation of Ser114 in the catalysis. This study provides the first structural description of a plant chloroplast endonuclease that is regulated by UV-stress response.
Histone H3K9 demethylase JMJD2B induces hepatic steatosis through upregulation of PPARγ2
Authors: Kim Ji-Hyun , Jung Dae Young , Nagappan Arulkumar , Jung Myeong Ho
Published: September 2018

Understanding the epigenetic mechanisms underlying the progression of hepatic steatosis is important for identifying new therapeutic targets against nonalcoholic fatty liver disease (NAFLD). We investigated the functional role of histone demethylase JMJD2B in the pathologic regulation of hepatic steatosis. JMJD2B expression was markedly increased in HepG2 cells treated with palmitate and oleate or liver X receptor agonist T09013178 and in the liver of high-fat diet (HFD)-induced obese mice. Overexpression of JMJD2B using adenovirus in HepG2 cells stimulated the expression of peroxisome proliferator-activated receptor γ2 (PPARγ2) and its steatosis target genes associated with fatty acid uptake and lipid droplet formation, resulting in increased intracellular triglyceride (TG) accumulation. Conversely, knocking down JMJD2B using siRNA reversed JMJD2B-mediated effects in HepG2 cells. The JMJD2B-dependent upregulation of PPARγ2 was associated with the removal of di- and trimethylation of histone H3 lysine 9 on the promoter of PPARγ2. Furthermore, exogeneous expression of JMJD2B using adenovirus in mice resulted in hepatic steatosis when fed a HFD, which was accompanied with increased expression of hepatic PPARγ2 and its steatosis target genes. Together, our results provide novel insights into the pivotal role of JMJD2B in the development of hepatic steatosis through upregulation of PPARγ2 and steatosis target genes.
Altering Compliance of a Load Carriage Device in the Medial-Lateral Direction Reduces Peak Forces While Walking
Authors: Martin Jean-Paul , Li Qingguo
Published: September 2018

Altering mechanical compliance in load carriage structures has shown to reduce metabolic cost and accelerative forces of carrying weight. Currently, modifications to load carriage structures have been primarily targeted at vertical motion of the carried mass. No study to date has investigated altering load carriage compliance in the medial-lateral direction. We developed a backpack specifically for allowing a carried mass to oscillate in the horizontal direction, giving us the unique opportunity to understand the effects of lateral mass motion on human gait. Previous modelling work has shown that walking economy can be improved through the interaction of a bipedal model with a laterally oscillating walking surface. To test whether a laterally oscillating mass can experimentally improve walking economy, we systematically varied step width above and below the preferred level and compared the effects of carrying an oscillating and fixed mass. Walking with an oscillating mass was found to reduce the accelerative forces of load carriage in both horizontal and vertical directions. However, load eccentricity caused the vertical force component to create a significant bending moment in the frontal plane. Walking with an oscillating mass led to an increase in the metabolic energy expenditure during walking and an increase in positive hip work during stance. The device’s ability to reduce forces experienced by the user, due to load carriage, holds promise. However, the requirement of additional metabolic energy to walk with the device requires future study to improve.
Carbon Nanomaterials in Electrochemical Detection
Authors: Moretto L. M. , Metelka R. , Scopece P.
Published: September 2018

High surface-to-volume ratio, high conductivity and electrocatalytic properties are some of the most interesting characteristics of carbon nanomaterials. Such exceptional properties have found a strong application in the field of electrochemical sensing. In this chapter we present the great relevance of the introduction of carbon nanomaterials, such as carbon nanotubes and graphene, for the development of new electrochemical sensors and biosensors. The possibility to exploit carbon nanomaterials for direct electrochemical sensing is illustrated. Furthermore, the easy modification of carbon materials with biomolecules enables the development of sophisticated and ultra-sensitive electrochemical sensors and biosensors for a plethora of important analytes and biomolecules, from DNA to cancer biomarkers. The possibility of coupling nanocarbon-based electrochemical sensors as detectors in separation techniques is briefly introduced. The most typical applications are described.
On-line coupling between capillary electrophoresis and microscale thermophoresis (CE–MST); the proof-of-concept
Authors: Nowak Paweł M. , Woźniakiewicz Michał
Published: September 2018

Capillary electrophoresis coupled on-line with microscale thermophoresis (CE–MST) may become a new method of choice for characterizing biomolecules and their interactions.
“Fix and assay”: separating in-cellulo sphingolipid reactions from analytical assay in time and space using an aldehyde-based fixative
Authors: Proctor Angela , Allbritton Nancy L.
Published: September 2018

Fixation of fluorescent sphingolipid-loaded cells enables cell metabolism and assay readout to be separated in time and space.
Exploring physicochemical space via a bioisostere of the trifluoromethyl and ethyl groups (BITE): attenuating lipophilicity in fluorinated analogues of Gilenya® for multiple sclerosis
Authors: Erdeljac Nathalie , Kehr Gerald , Ahlqvist Marie , Knerr Laurent , Gilmour Ryan
Published: September 2018

The BITE bioisostere of Et and CF3 allows lipophilicity to be tempered in analogues of the multiple sclerosis drug Gilenya®.
Crystal structures of ordered and plastic-crystalline phases of iso-butyllithium by X-ray powder diffraction
Authors: Bodach Alexander , Fink Lothar , Schmidt Martin U.
Published: September 2018

The crystal structures of solid, donor-free i-BuLi at different temperatures were determined from X-ray powder diffraction data.
Optically pure 2-(quinolin-8-yloxy)cyclohexan-1-ol as a practical agent for molecular recognition by NMR and fluorescence spectroscopy
Authors: Khanvilkar Aditya N. , Bedekar Ashutosh V.
Published: September 2018

Optically pure 2-(quinolin-8-yloxy)cyclohexan-1-ol 1, obtained via simple chemical and bio-catalytic steps, was used as a chiral solvating agent for molecular recognition of the enantiomers of acids.
Metallaaromatic biaryl atropisomers
Authors: Talavera M. , Peña-Gallego A. , Alonso-Gómez J. L. , Bolaño S.
Published: September 2018

The birth of metallaaromatic biaryl atropisomers: synthesis, structural elucidation, and theoretical analysis of the first examples is reported.
BaCaLu2F10:Ln3+ (Ln = Eu, Dy, Tb, Sm, Yb/Er, Yb/Ho) spheres: ionic liquid-based synthesis and luminescence properties
Authors: Liu Wei , Sun Qi , Yan Ming , Song Yanhua , Zhou Xiuqing , Sheng Ye , Zheng Keyan , Zou Haifeng
Published: September 2018

Alkaline earth metal rare earth fluoride BaCaLu2F10:Ln3+ (Ln = Eu, Dy, Tb, Sm, Yb/Er, Yb/Ho) submicrospheres with uniform morphology and size were synthesized via a facile ionic liquid-based hydrothermal route. The down- and up-conversion luminescence has been investigated.
Geometrically intricate sheet-on-pillar/flake hierarchy embracing cobaltosic and manganese oxides over flexible carbon scaffold for binder-free high-energy-density supercapacitor
Authors: Thakur S. , Maiti S. , Paul T. , Besra N. , Sarkar S. , Chattopadhyay K. K.
Published: September 2018

Sheet-on-rod/flake hierarchy embracing Co3O4 and MnO2 on carbon fabric is used for binder-free high-energy-density supercapacitor. Electrochemical behaviour is illuminated on the basis of shape-porosity-property correlation.
Li2Gd4(MoO4)7 crystal preparation and spectral properties applied to 2.0 μm lasers
Authors: Sun Shijia , Wei Qi , Chen Weidong , Lou Fei , Zhong Degao , Hu Chen , Zhang Lizhen , Lin Zhoubin , Teng Bing
Published: September 2018

The disordered structures and polarized spectral properties of the Tm3+/Ho3+:Li2Gd4(MoO4)7 crystal reveal its promising potential for generating tunable and ultrafast pulse lasers.
Fabrication and characterization of nanoporous Cu–Sn intermetallicsviadealloying of ternary Mg–Cu–Sn alloys
Authors: Zhang Chi , Xie Zhuohong , He Xin , Liang Ping , Zeng Qingguang , Zhang Zhonghua
Published: September 2018

The dealloying of Mg–Cu–Sn alloys leads to the formation of nanoporous Cu–Sn intermetallics.
QM and ONIOM studies on thermally activated delayed fluorescence of copper(i) complexes in gas phase, solution, and crystal
Authors: Gao Yuan-Jun , Chen Wen-Kai , Wang Zi-Rui , Fang Wei-Hai , Cui Ganglong
Published: September 2018

QM and ONIOM studies reveal the thermally activated delayed fluorescence mechanism of two Cu(i) complexes.
EPR sensing of metal and organic cations using a novel spin-labelled dibenzo-24-crown-8-ether
Authors: Gualandi Lorenzo , Franchi Paola , Credi Alberto , Mezzina Elisabetta , Lucarini Marco
Published: September 2018

Novel dibenzo-24-crown ether substituted nitroxides and their use as spin probes for the detection of cation guests by EPR are reported.
Molecules mimicking atoms: monomers and dimers of alkali metal solvated electron precursors
Authors: Ariyarathna Isuru R. , Pawłowski Filip , Ortiz Joseph Vincent , Miliordos Evangelos
Published: September 2018

Tetra-amino lithium and sodium complexes M(NH3)0,−4 (M = Li, Na) have one or two electrons that occupy diffuse hydrogenic type orbitals distributed chiefly outside the M(NH3)4+ core. Two such neutral species can bind to form a dimer which can be seen as the analogue of molecular hydrogen.
NiFe2O4nanoparticles coated on 3D graphene capsule as electrode for advanced energy storage applications
Authors: AL-Rubaye Shaymaa , Rajagopalan Ranjusha , Subramaniyam Chandrasekhar , Tai Zhixin , Xian Jian , Wang Xiaolin , Dou Shi Xue , Cheng Zhenxiang
Published: September 2018

The 3D nanostructured NiFe2O4/graphene capsules employed in this study exhibited specific capacitance of 1028 F g−1with a remarkable cycling stability of 10 000 cycles.
Storing electricity as chemical energy: beyond traditional electrochemistry and double-layer compression
Authors: Antonietti Markus , Chen Xiaodong , Yan Runyu , Oschatz Martin
Published: September 2018

Local electric fields in IL-based supercapacitors can change the ionic coordination structure to store electric energy in the bulk of filled mesopores.
A novel fluorescence strategy for mercury ion and trypsin activity assay based on nitrogen-doped graphene quantum dots
Authors: Su Dandan , Wang Mengke , Liu Qing , Qu Zhengyi , Su Xingguang
Published: September 2018

Fluorescent detection of Hg2+and trypsin based on trypsin-modulated competition between Hg2+, N-GQDs and HSA.
Toward the total synthesis of patellazole B: synthesis of an advanced C1–C25 fragment corresponding to the macrocyclic skeleton
Authors: Phillips Andrew W. , Anketell Matthew J. , Balan Tudor , Lam Nelson Y. S. , Williams Simon , Paterson Ian
Published: September 2018

A modular and highly convergent approach enables the assembly of an advanced intermediate towards the total synthesis of patellazole B – a promising anticancer agent.
Xylopsides A–D, four rare guaiane dimers with two unique bridged pentacyclic skeletons from Xylopia vielana
Authors: Xie Yang-Guo , Guo Yi-Gong , Wu Guo-Jing , Zhu Sheng-Lan , Cheng Tao-Fang , Zhang Yu , Yan Shi-Kai , Jin Hui-Zi , Zhang Wei-Dong
Published: September 2018

Four compounds with two bridged pentacyclic skeletons between two guaiane-type sesquiterpenes, which were characterized as two different bridged ring systems.
Dual catalysis system for ring-opening polymerization of lactones and 2,2-dimethyltrimethylene carbonate
Authors: Bai Junhua , Wang Jinhua , Wang Yan , Zhang Lifang
Published: September 2018

The dual catalysis system exhibit the characteristics of a controlled ROP and suitable activities for the ROP of lactones and carbonates. Polymers prepared through this dual catalytic route possess predictable molecular weights, narrow polydispersities, and high end-group fidelity.
Long read range Class‐3 UHF RFID system based on harmonic backscattering
Authors: Chen Xianliang , Chen Yong , Zhang Hualei , Yan Na , Wang Junyu , Min Hao , Zheng Li‐Rong
Published: September 2018

A high sensitivity Class‐3 ultra high‐frequency (UHF) radio‐frequency identification (RFID) system based on harmonic backscattering to achieve a long read‐range is presented. Harmonic backscattering is a promising solution to solve the carrier leakage issue of UHF RFID reader to improve the sensitivity. In the proposed RFID system based on harmonic backscattering, the RFID reader transmits data with the fundamental frequency carrier and receives data with its second harmonic carrier, and the RFID tag employs a rectifier to generate both DC power and the second harmonic carrier for backscattering without impedance mismatch. The first harmonic Class‐3 UHF RFID system based on National Instruments software defined radio platform is proposed and implemented. The proposed semi‐passive harmonic RFID tag has dBm sensitivity. Test results show that the harmonic RFID system has a dBm sensitivity with the harmonic RFID tag whose signal‐to‐blocker ratio is dB at 20 m communication distance.
Depth‐based end‐to‐end deep network for human action recognition
Authors: Chaudhary Sachin , Murala Subrahmanyam
Published: September 2018

Recognition of human actions from videos can be improved if depth information is available. Depth information certainly helps in segregating foreground motion from the background. Single image depth estimation (SIDE) is a commonly used method for the analysis of weather degraded images. In this study, the idea of SIDE is extended to human action recognition (HAR) on datasets where depth information is not available. Several depth‐based HAR algorithms are available but all of them are using the depth information given with the dataset. Some other methods are using depth motion map which refers to the depth of motion in a temporal direction. Here, a new depth‐based end‐to‐end deep network is proposed for HAR in which the frame‐wise depth is estimated and this estimated depth is used for processing instead of RGB frame. As colour information is not required for estimating motion, a single channel depth map is used for estimating motion in the video. It makes the system computationally efficient. The proposed method is tested and verified on three benchmark datasets namely JHMDB, HMDB51 and UCF101. The proposed method outperforms the existing state‐of‐the‐art methods for HAR on all the three tested datasets.
Comprehensive mixed‐integer linear programming model for distribution system reconfiguration considering DGs
Authors: Teshome Dawit F. , Lian Kuo Lung
Published: September 2018

Distribution system reconfiguration (DSR) is a critical process that improves the power transfer efficiency and reduces the over‐all operational cost. There have been various methods for addressing the DSR problems. Recently, DSR problems formulated in mixed‐integer linear programming (MILP) has gained popularity as they generally can be solved by the state‐of‐the‐art commercially accessible linear programming solvers, and is able to solve the system with thousands of unknown variables within a reasonable time. However, in some MILP formulations, the distribution line losses are omitted in the nodal power injections for the sake of simplicity. This compromises the accuracy of the linearised model and contributes to the disparity between the MILP and the true non‐linear model. Hence, in this study, new formulations are introduced for embedding the expressions of line losses inside load flow equations so that the deviations between the modelled and exact losses notably reduce. Moreover, other novel formulations have also been presented for simultaneously optimising distributed generation (DG) locations and sizes, while at the same time considering various DG's modes of connection to the distribution grid. The validity and effectiveness of the proposed MILP model is tested on standard IEEE systems and actual distribution network.
Comparison of altered mineral information extracted from ETM+, ASTER and Hyperion data in Águas Claras iron ore, Brazil
Authors: Huang Shuang , Chen Sheng‐Bo , Zhang Yuan‐Zhi
Published: September 2018

Locations used to validate extraction results from remote sensing images are typically ground rock samples. However, remotely sensed image pixels are 30 m2 with mixing spectra. Rock samples cannot fully represent extraction results on an image. Here, alteration information associated with the Águas Claras, Brazil iron deposit was analysed using a Landsat Enhanced Thematic Mapper plus (ETM+), a Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Hyperion data, all with 30 m resolution. With improvements in spectral resolution, extracted results have changed from the alteration information to altered rocks and minerals. The accuracy of alteration information has improved continuously as data extracted from these sources verify one another. Minerals extracted using Hyperion corresponded to altered assemblages identified from ASTER. Both were consistent with alteration information extracted from ETM+ at the same location. Alteration information extracted from three remote images were located within ore formations, and controlled by the north‐east trending faults and matched well with known deposits. Information extraction based on the integrated application of multi‐source remote sensing data could compensate for deficiencies in using single data. These results can verify one another to improve data reliability particularly in the areas inaccessible and lacking sufficient field confirmation.
Keypoints based enhanced multiple copy‐move forgeries detection system using density‐based spatial clustering of application with noise clustering algorithm
Authors: Soni Badal , Das Pradip K. , Thounaojam Dalton Meitei
Published: September 2018

In this study, the problem of detecting if an image has tampered is inquired; especially, the attention has been paid to the case in which the portion of an image is copied and then pasted onto another region to create a duplication or to hide some important portion of the image. The proposed copy‐move forgery detection system is based on the scale‐invariant feature transform (SIFT) features extraction and density‐based clustering algorithm. The extracted SIFT features are matched using the generalised two nearest neighbours (2NN) procedure. Thereafter, the density‐based clustering algorithm is utilised to improve the detection results. The proposed system is tested using MICC‐F220, MICC‐F2000 and MICC‐F8multi datasets. Due to the generalised 2NN matching procedure, the proposed system is able to detect multiple forgeries present in the image. Experimental results show that the performance of the system is quite satisfactory in terms of computational time as well as detection accuracy.
Investigation of a DSRC‐based end of queue collision warning system by considering real freeway data
Authors: Liu Yang , Wang Zhong‐Li , Cai Bai‐Gen
Published: September 2018

As a rapidly developing technology, dedicated short‐range communications (DSRC) can facilitate the solution to increasingly outstanding traffic safety problems, especially for collision warning. The conventional collision warning system using DSRC is based on the kinematic model, which depends on accurate velocity and position information. However, the reliability of the system may be reduced due to low DSRC penetration rate, communication range constraint, and vehicle positioning error. In this study, a DSRC‐based end of queue collision warning system is proposed without concerning position information. The warning criterion is defined according to the real traffic data rather than experimental data. According to the warning strategy, warning evaluation proves that the strategy is effective under low DSRC penetration rate condition. Despite the DSRC penetration rate, traffic and communication influential factors are also taken into consideration in the evaluation model. The warning performance under different weather conditions is analysed based on the simulation result. Comparison studies demonstrate that the proposed algorithm outperforms the variable speed limits warning strategy based on the loop detector.
GPS‐data‐driven dynamic destination prediction for on‐demand one‐way carsharing system
Authors: Wang Lei , Zhong Yugao , Ma Wanjing
Published: September 2018

On‐demand one‐way carsharing systems are increasingly gaining popularity nowadays and the market is growing unprecedentedly. However, operating techniques such as vehicle surveillance and fleet management fall behind the industrial development. Practice on EVCARD – an on‐demand one‐way electric vehicle carsharing system operating in Shanghai – raises an issue on dynamically predicting the user destinations, in order to support decisions on dynamic fleet management. This study presents a global positioning system (GPS)‐data‐driven method to solve the problem. The historical vehicle GPS data is enabled to match the user current trajectories and infer their possible destinations. Based on the GPS trajectory similarity measurement, the study presents a four‐step procedure, including (i) similarity calculation, (ii) most‐similar track detection, (iii) adjustment, and (iv) sorting. The method also takes the station correlations and the user historical destinations into account. A case study is given to demonstrate the dynamic prediction procedure of this method. Experiment on 96,821 valid test tracks shows that the positive prediction rate can be above 92% if the test trip has been completed over 70%. Factors that may influence the prediction result are additionally discussed, which include the existence of round‐trips, the coverage of samples, and the alternatives of destinations.
Robust target motion analysis using the possibility particle filter
Authors: Ristic Branko , Houssineau Jeremie , Arulampalam Sanjeev
Published: September 2018

Bearings‐only target motion analysis (TMA) is the process of estimating the state of a moving emitting target from noisy measurements collected by a single passive observer. The focus of this study is on recursive TMA, traditionally solved using the Bayesian filters (e.g. extended or unscented Kalman filters, particle filters). The TMA is a difficult problem and may result in track divergence, especially when the assumed probabilistic models are imperfect or mismatched. As a robust alternative to Bayesian filters for TMA, the authors present a recently proposed stochastic filter referred to as the possibility filter. The filter is implemented in the sequential Monte Carlo framework, and named the possibility particle filter. This study demonstrates its superior performance against the standard (Bayesian) particle filter in the presence of a model mismatch, while in the case of the exact model match, its performance equals that of the standard particle filter.
Method for scatterer trajectory association of sequential ISAR images based on Markov chain Monte Carlo algorithm
Authors: Liu Lei , Zhou Feng , Bai Xue‐Ru
Published: September 2018

Based on sequential inverse synthetic aperture radar (ISAR) images, the three‐dimensional target structure can be reconstructed using the factorisation method. However, it requires accurate scatterer trajectory formation, which is difficult due to the occlusion and trajectory crossing. To address this problem, the authors propose a novel scatterer trajectory association method based on Markov chain Monte Carlo (MCMC) algorithm. First, they derive the ellipse movement characteristics of each scatterer trajectory under stationary rotational motion model of the observed target. Then, by computing the signal‐to‐noise ratio of the compressed echoes, the number and positions of the scatterers in each ISAR image can be extracted precisely and efficiently through two‐dimensional estimation of signal parameters via rotational invariance techniques. Next, they present a Bayesian model and inference algorithm for the scatterer trajectory association problem. MCMC is applied to estimate the scatterer trajectory matrix. Particularly, they design new prior and likelihood evaluation criterions in MCMC by making use of the ellipse movement characteristics of each scatterer trajectory. Experimental results on simulated data validate the effectiveness of the proposed method.
Modeling stress upturn at high strain rates for ductile materials
Authors: Partom Yehuda
Published: September 2018

Ductile materials (mainly metals) exhibit a sharp upturn of stress at strain rates around 103 to 104/s, which is not specific to a certain type of material. It is important to consider stress high rate upturn when dealing with high rate loading, such as shock loading and unloading. Using classical strength models, usually calibrated at not so high rates, may lead to errors with high rate loading and not so high pressures. Here we model high rate upturn on the macroscale. We assume that the upturn mechanism is also responsible for the 4th power law mechanism put forward by Swegle and Grady. In the past we calibrated our overstress dynamic viscoplasticity model for aluminium from 4th power law data. Here we use this calibration to predict the high rate stress upturn.
Strength Model Evaluation Based on Experimental Measurements of Necking Profile in Ductile Metals
Authors: Peroni Lorenzo , Scapin Martina
Published: September 2018

The reliability of the numerical results strongly depends upon the choice of the constitutive models, which sometimes requires an ad-hoc calibration of the parameters starting from experimental results. Often, the tension test is chosen since it allows obtaining a big amount of data, but in case of ductile materials, in which the specimen could be subjected to high value of plastic strain before the fracture, it is necessary to properly manage the experimental results. For low values of deformation, the deformation of the gage length of the specimen is uniform and the true stress can be easily derived from the longitudinal one and considered as the equivalent stress. At the onset of necking, geometrical instability and concentration of deformation are developed. In the scientific literature several different approaches have been proposed in order to estimate the equivalent stress distribution in the post-necking regime. In this work, a new approach was proposed by the combination of digital image analysis and numerical inverse method. The evolution of the profile deformation of the specimen observed during the test is directly used to identify the constitutive relation of the material in case of dynamic tensile tests.
Numerical Simulation on the specimen dynamic plastic deformation behaviour in the torsional split Hopkinson bar test
Authors: Gang Chen , Xicheng Huang , Junhong Chen , Weizhou Zhong
Published: September 2018

The torsional split Hopkinson bar (SHB) is an important method to study the dynamic shear behaviour and shear localization of materials under high strain rates. Different specimen sizes were used in literatures, and the size of the specimen might have an effect on the experimental results. Numerical simulation on torsional SHB tests was carried out with LS-DYNA. The strain signal on the incident and transmitted bars were obtained from the simulation just as the experiment. Then the numerical strain-stress relationship of the material was derived from the numerical strain signal using the experiments data process of torsional SHB. The agreement between numerically derived strain-stress results and the specimen material properties specified in numerical modelling indicates that the torsional SHB is applicable to study the dynamic shear behaviour of materials under high strain rates. The specimen gauge diameter has no significant effect on the dynamic torsional test result. However, higher adhesive strength is required to fix the larger gauge diameter specimen on the bars. The specimen gauge thickness has little effect on the experimental results with a modified formula to calculate the specimen stress. Still, the increase of specimen gauge thickness will lead to the increase of non-uniformity of specimen stress and strain (strain rate). Based on the simulation analysis, suggestions on the specimen size design are given as well.
An improvement of the Lagrangian analysis method based on particle velocity profiles
Authors: Ding Yuanyuan
Published: September 2018

In general, techniques used in studies on dynamic behaviour of materials could be classified into two categories, namely the split Hopkinson pressure bar technique (SHPB) and the wave propagation technique (WPT). Lagrangian analysis method is one of the most famous methods in WPT. The traditional Lagrangian analysis based on the particle velocity wave-profiles measurements should consider a boundary condition, because it involves integral operations. However, the boundary stress data in some cases cannot be detected or determined by the experimental measures. To tackle this situation, this paper presents a modified Lagrangian analysis method which does not involve the boundary stress computation. Starting from the path-lines method and utilizing the zero-initial condition, the material constitutive stress-strain curves under high strain-rates is deduced from only observing the particle velocity curve measurements. The dynamic stress/strain wave-profiles of the PMMA material, as a paradigm, are numerically studied using the proposed method, which are well in agreement with the theoretical result using the method of characteristics, which confirms the reliability and validity of the presented method.
Thermo-elastic-plastic Model for Numerical Simulation of Fasteners Destruction Under Gasodynamic Impulsive Pressure
Authors: Chernobryvko Marina , Avramov Konstantin , Uspensky Boris , Tonkonogenko Anatoly , Kruszka Leopold
Published: September 2018

Modern rocketry widely employs a method of gasodynamic impulse destruction of bondings which may occur at high variety of temperatures. To design fasteners correctly it is necessary to have the ability to calculate fastener’s destruction time at a given pressure. Numerical research is an expedient approach to this problem. A mathematical model of a high-speed deformation and failure in fastening elements of special rocket structures due to gasodynamic wave-impact impulse loading is developed. A technique for numerical analysis of the deformation of fasteners and failure duration is proposed. To perform such analysis a set of factors such as: static stress-strain state due to assembling; thermo-elastic deformation of fasteners due to environment temperature; high-speed dynamical elastic-plastic failure of fastening elements are taken into consideration. The failure model due to the plastic flow considers dynamical material properties. As a criterion of failure maximum plastic deformation is chosen. The technique is implemented for several types of fasteners. Numerical simulation using finite elements method is conducted. The results of the numerical research are well-correlated with experimental data.
Investigation of the behaviour of functionally graded materials under impact loads
Authors: Orlov Maxim , Orlov Yuri , Glazyrin Viktor , Orlova Yulia
Published: September 2018

The impact response of unidirectional FGM is studied in detail. The behaviour of the material is described by the classical complex model of continuum mechanics. The calculations are performed in 2D axisymmetric approach using a modified Lagrangian method. The mathematical model and numerical method was developed at the Research Institute of Applied Mathematics and Mechanics of Tomsk State University. In the beginning, test calculations were carried out. The evolution of the destruction of homogeneous and FGM-samples, including the time of formation of the first foci of destruction, spall was studied. The time dependences of the velocity of the free surface, hydrostatic pressure, and the damage parameter were constructed. The presence of a graded substrate led to an increase in impact resistance at velocities up to 275 m/s.
Development of a constitutive model for DPX2 explosive
Authors: Church Philip , Gould Peter , Williamson David
Published: September 2018

There is a significant challenge in simulating the behaviour of PBXs under high strain rate impact loading. A Porter-Gould physically based constitutive model has been developed for the DPX2 explosive. A series of quasi-static compression and tensile tests over a range of temperatures were performed together with DMA tests to calibrate the model. In particular tests were performed for different L/D ratios to understand the complex localisation and damage behaviour of the material. High rate tests on the compression Split Hopkinson Pressure Bar (SHPB) for a range of temperatures were then used for validation of the model under idealised stress states. Some model development is still required, particularly at lower temperatures near the glass transition temperature. In addition a series of classical Taylor Tests were used to validate the model under impact loading conditions at room temperature. The DYNA3D simulations gave very good results compared to the experiments for these impact conditions.
Modeling of a Dynamic Thermal Load Generated by a 7TeV Proton Beam Impacting the Beam Dump of the Large Hadron Collider at CERN
Authors: Polzin Tobias , Peiillo-Marcone Antonio , Bianchi Laura , Calviani Marco , Frankl Matthias , Guinchard Michael , Lechner Anton
Published: September 2018

The two beam dumps of the Large Hadron Collider (LHC), made up mostly of low-density graphite, are responsible for absorbing the high-energy particle beams when ejected from the accelerator. In the frame-work of the project to improve the luminosity in the LHC, the beam intensity will be increased by a factor of around two in the coming years. The dominant load on the dump assembly is the energy deposited in the material by the 7 TeV proton beam. Thermomechanical simulations have to be performed to ensure the safe operation of the dump through assessing the integrity in the future. To date, the particle beam contains an average energy of 370 MJ, which is sent to the dump in a sweep movement within around 80 µs. Based on the large dimensions of the dump core and considering the highly dynamic nature of this load, an explicit code like LS-Dyna® was deemed to be best suited for these studies. This paper presents the methodology proposed to model the discrete time structure of the load, caused by the interaction between the particle beam and the dump. Results of the application of this technique, to determine the temperature, stresses and wave propagation on the downstream wall of this device, are described here. In addition to the methodology of the load application, the results of standard quasi-static material tests on the low-density graphite material in the beam dump are presented, to assess the general nature of the material behavior. These experiments will be the basis for a dynamic test campaign to construct a comprehensive material model, as the graphite used in this device has never been fully characterized under such loading conditions.
Temperature dependent crack initiation of 42CrMo4 steel at high loading rates
Authors: Henschel Sebastian , KrÜger Lutz
Published: September 2018

Dynamic crack initiation with crack tip loading rates K˙ of approximately 2 ‧ 106 MPa√ms− in high-strength 42CrMo4 steel was investigated. To this end, a recently developed split Hopkinson pressure bar with four-point bending was utilized. V-notched and precracked Charpy specimens were tested. The tests were performed at temperatures of –40 °C and 20 °C. The loading of the specimen was determined by analyzing the strain in the incident and transmission bars. Furthermore, strain gauges at the specimen’s surface were applied to measure the crack tip loading. High-speed photography complemented the analysis of the specimens loading and the detection of the crack initiation. Fracture surface analysis by means of scanning electron microscopy enabled the measurement of the fracture surface topography and, consequently, stretch zone height and width. Hence, the macroscopically measured dynamic crack initiation toughness was correlated with the toughness at microscopic scale. It was observed that the resistance against dynamic crack initiation decreased with decreasing temperature. Microscopically, a decrease in toughness was analogously observed. Non-metallic inclusions resulted in crack path deflection with localized shear zones. After a small stable crack extension, cleavage fracture was observed.