bluuebunny/crossref_metadata_2025 huggingface dataset:
New perspectives on Solid Earth Geology from Seismic Texture to Cooperative Inversion
Authors: Le Cuong Van Anh , Harris Brett D. , Pethick Andrew M.
Published: October 2019

Seismic and electromagnetic methods are fundamental to Solid Earth research and subsurface exploration. Acquisition cost reduction is making dense 3D application of these methods accessible to a broad range of geo-scientists. However, the challenge of extracting geological meaning remains. We develop the concept of “textural domaining” for 3D seismic reflectivity data. Dip-steered seismic texture attributes are combined with unsupervised learning to generate sets of volume rendered images accompanied by a seismic texture reference diagram. These methods have the potential to reveal geological and geotechnical properties that would otherwise remain hidden. Analysis of seismic texture presents particular value in hard-rock settings where changes in velocity may be negligible across rock volumes exhibiting significant changes in rock mass texture. We demonstrate application and value of textural domaining with three industry-scale field examples. The first example links seismic texture to rock type along a 400 km long transect through central Australia. The second and third examples partition dense 3D seismic data based on texture for complex hard rock terrains in Nevada, USA and Kevitsa, Finland. Finally, we demonstrate application of domaining within texture guided cooperative inversion of 3D seismic reflectivity and magnetotelluric data to provide new perspectives on Solid Earth geology.
Lewis acid-catalyzed synthesis of silafluorene derivatives from biphenyls and dihydrosilanes via a double sila-Friedel–Crafts reaction
Authors: Dong Yafang , Takata Yuta , Yoshigoe Yusuke , Sekine Kohei , Kuninobu Yoichiro
Published: October 2019

The synthesis of silafluorene derivatives from aminobiphenyl compounds and dihydrosilanes via a double sila-Friedel–Crafts reaction using a borane catalyst has been achieved.
Direct comparison of dithienosilole and dithienogermole as π-conjugated linkers in photosensitizers for dye-sensitized solar cells
Authors: Adachi Yohei , Nabeya Taishi , Nomura Takanori , Kondo Keisuke , Kawakami Keigo , Ooyama Yousuke , Ohshita Joji
Published: October 2019

The photophysical properties and DSSC performances of dithienosilole (DTS) and dithienogermole (DTG) containing photosensitizing dyes were directly compared.
Two mononuclear dysprosium(iii) complexes with their slow magnetic relaxation behaviors tuned by coordination geometry
Authors: Yu Shui , Chen Zilu , Hu Huancheng , Li Bo , Liang Yuning , Liu Dongcheng , Zou Huahong , Yao Di , Liang Fupei
Published: October 2019

We report here two field-induced single-ion magnets of Dy(iii), which present octahedral and pentagonal–bipyramidal coordination geometries, respectively, with their magnetic performances tuned by the coordination geometries of Dy(iii).
Fluorination as tool to improve bioanalytical sensitivity and COX-2-selective antitumor activity of cobalt alkyne complexes
Authors: Baecker Daniel , Obermoser Victoria , Kirchner Elisabeth Anna , Hupfauf Andrea , Kircher Brigitte , Gust Ronald
Published: October 2019

Fluorination of the lead Co-ASS yielded antitumor active cobalt alkyne complexes that exhibited both improved COX-2 selectivity and better bioanalytical sensitivity.
Anhydrous nanoprecipitation for the preparation of nanodispersions of tenofovir disoproxil fumarate in oils as candidate long-acting injectable depot formulations
Authors: Hobson James J. , Curley Paul , Savage Alison C. , Al-khouja Amer , Siccardi Marco , Flexner Charles , Meyers Caren Freel , Owen Andrew , Rannard Steve P.
Published: October 2019

The facile formation of drug nanoparticles in injectable/ingestible oils, of water-soluble antiretroviral tenofovir disoproxil fumarate, using a novel nanoprecipitation is presented with studies showing drug release into relevant aqueous media.
Iodine-catalyzed guanylation of amines withN,N′-di-Boc-thiourea
Authors: Rong Hao-Jie , Yang Cui-Feng , Chen Tao , Xu Ze-Gang , Su Tian-Duo , Wang Yong-Qiang , Ning Bin-Ke
Published: October 2019

Iodine-catalyzed guanylation of amines withN,N′-di-Boc-thiourea is especially useful for both electronically and sterically deactivated primary anilines.
Utilizing the aggregation-induced emission phenomenon to visualize spontaneous molecular directed motion in the solid state
Authors: Liu Jianxun , Xing Chang , Wei Donghui , Deng Qianqian , Yang Cuiping , Peng Qiuchen , Hou Hongwei , Li Yuanyuan , Li Kai
Published: October 2019

A rod-like AIEgen was developed for real-time visualization of spontaneous molecular directed motion in situ, providing rich kinetic information.
Synthesis of silacyclopent-2-en-4-ols via intramolecular [2 + 2] photocycloaddition of benzoyl(allyl)silanes
Authors: Vale João R. , Valkonen Arto , Afonso Carlos A. M. , Candeias Nuno R.
Published: October 2019

Organosilicon compounds are versatile units with a wide range of uses from medicinal chemistry to the field of organic electronics.
Compatibility driven self-strengthening during the radical-responsive remolding process of poly-isoprene vitrimers
Authors: Ling Fangwei , Liu Zhenwei , Chen Mokun , Wang Hao , Zhu Yong , Ma Changshu , Wu Jinrong , Huang Guangsu
Published: October 2019

A compatibility-tailoring strategy is employed to fabricate poly-isoprene vitrimers with self-strengthening capabilities during the remolding process.
Penetration effect of connected and automated vehicles on cooperative on‐ramp merging
Authors: Ding Jishiyu , Peng Huei , Zhang Yi , Li Li
Published: October 2019

Earlier work has established a centralised cooperative merging framework of optimally coordinating two strings of connected and automated vehicles (CAVs) passing through the on‐ramp merging zone. The proposed merging strategy is capable of making a good trade‐off between performance and computational cost. In this study, the authors address the problem of optimally coordinating CAVs under mixed traffic conditions, where both CAVs and human‐driven vehicles (non‐CAVs) travel on the roads, so as to enhance efficiency while guaranteeing safety constraints. A hierarchical cooperative merging framework is proposed for CAVs, which integrates merging sequence scheduling strategies (high level) and motion planning methods (low level). The impacts of CAV penetration (i.e. the fraction of CAVs relative to all vehicles) on throughput, delay, fuel consumption and emission are also investigated under different traffic demands. Simulation‐based case studies indicate that the performance improvement becomes more significant as the CAV penetration rate increases and about 30% CAV penetration can effectively mitigate the shockwave and reduce traffic congestion.
Investigating of bidirectional dc–dc converter in different operational modes and designing of component considering the minimum OVR and filter size
Authors: Babaei Ebrahim , Mashinchi Maheri Hamed , Sabahi Mehran
Published: October 2019

This study investigates a bidirectional dc–dc converter. The energy transmission techniques are analysed. A design procedure based on output voltage ripple (OVR) and filter size is implemented on a bidirectional dc–dc converter. The OVR of the converter is analysed in different operation modes. The relations between the maximum OVR (MOVR) (the worst condition) and the converter component parameters are deduced, and the minimum inductance value is calculated to ensure the MOVR and filter size minimisation in both of the step‐up and step‐down operations. The effect of coupling coefficient of the coupled inductors on the OVR is investigated. Finally, experimental and simulation results are provided to validate the theoretical analyses.
ODEA: Orbital Dynamics in a complex Evolving Architecture
Authors: Rodet L. , Beust H. , Bonnefoy M. , De Rosa R. J. , Kalas P. , Lagrange A.-M.
Published: October 2019

Context. Mixed-variable symplectic integrators are widely used in orbital dynamics. However, they have been developed for Solar system-type architectures, and can not handle evolving hierarchy, in particular in systems with two or more stellar components. Such configuration may have occurred in the history of HD 106906, a tight pair of F-type stars surrounded by a debris disk and a planetary-mass companion on a wide orbit.

Aims. We present the new algorithm ODEA, based on the symplectic algorithm Swift HJS, that can model any system (binary,...) with unstable architecture. We study the peculiar system HD 106906 as a testcase for the code.

Methods. We define and compute a criterion based on acceleration ratios to indicate when the initial hierarchy is not relevant anymore. A new hierarchy is then computed. The code is applied to study the two recently evidenced fly-bys that occurred on system HD 106906, to determine if they could account for the wide orbit of the planet. Thousands of simulations have been performed to account for the uncertainty on the perturbers coordinates and velocities.

Results. The algorithm is able to handle any change of hierarchy, temporary or not. We used it to fully model HD 106906 encounters. The simulations confirm that the fly-bys could have stabilized the planet orbit, and show that it can account for the planet probable misalignment with respect to the disk plane as well as the disk morphology. However, that requires a small distance at closest approach (≲0.05 pc), and this configuration is not guaranteed.

Conclusions. ODEA is a very good choice for the study of non-Solar type architecture. It can now adapt to an evolving hierarchy, and is thus suitable to study capture of planets and dust. Further observations of the perturbers, in particular their radial velocity, are required to conclude on the effects of the fly-by on system HD 106906.
Optimization of surface flux transport models for the solar polar magnetic field
Authors: Petrovay K. , Talafha M.
Published: October 2019

Context. The choice of free parameters in surface flux transport (SFT) models describing the evolution of the large-scale poloidal magnetic field of the Sun is critical for the correct reproduction of the polar magnetic flux built up during a solar cycle, which is known to be a good predictor of the amplitude of the upcoming cycle.

Aims. For an informed choice of parameters it is important to understand the effects of and interplay among the various parameters and to optimize the models for the polar magnetic field.

Methods. Here we present the results of a large-scale systematic study of the parameter space in an SFT model where the source term representing the net effect of tilted flux emergence was chosen to represent a typical, average solar cycle as described by observations.

Results. Comparing the results with observational constraints on the spatiotemporal variation of the polar magnetic field, as seen in magnetograms for the last four solar cycles, we mark allowed and excluded regions in the 3D parameter space defined by the flow amplitude u0, the magnetic diffusivity η and the decay time scale τ, for three different assumed meridional flow profiles.

Conclusions. Without a significant decay term in the SFT equation (i.e., for τ >  10 yr) the global dipole moment reverses too late in the cycle for all flow profiles and parameters, providing independent supporting evidence for the need of a decay term, even in the case of identical cycles. An allowed domain is found to exist for τ values in the 5–10 yr range for all flow profiles considered. Generally higher values of η (500–800 km2 s−1) are preferred though some solutions with lower η are still allowed.
Shape model and spin-state analysis of PHA contact binary (85990) 1999 JV6 from combined radar and optical observations
Authors: Rożek A. , Lowry S. C. , Nolan M. C. , Taylor P. A. , Benner L. A. M. , Fitzsimmons A. , Zegmott T. J. , Weissman P. R. , Green S. F. , Rozitis B. , Snodgrass C. , Smythe W. D. , Hicks M. D. , Howell E. S. , Virkki A. K. , Aponte-Hernandez B. , Rivera-Valentín E. G. , Rodriguez-Ford L. A. , Zambrano-Marin L. F. , Brozović M. , Naidu S. P. , Giorgini J. D. , Snedeker L. G. , Jao J. S. , Ghigo F. D.
Published: October 2019

Context.The potentially hazardous asteroid (85990) 1999 JV6 has been a target of previously published thermal-infrared observations and optical photometry. It has been identified as a promising candidate for possible Yarkovsky-O’Keefe-Radzievskii-Paddack (YORP) effect detection.

Aims.The YORP effect is a small thermal-radiation torque considered to be a key factor in spin-state evolution of small Solar System bodies. In order to detect YORP on 1999 JV6 we developed a detailed shape model and analysed the spin-state using both optical and radar observations.

Methods.For 1999 JV6, we collected optical photometry between 2007 and 2016. Additionally, we obtained radar echo-power spectra and imaging observations with Arecibo and Goldstone planetary radar facilities in 2015, 2016, and 2017. We combined our data with published optical photometry to develop a robust physical model.

Results.We determine that the rotation pole resides at negative latitudes in an area with a 5° radius close to the south ecliptic pole. The refined sidereal rotation period is 6.536787 ± 0.000007 h. The radar images are best reproduced with a bilobed shape model. Both lobes of 1999 JV6 can be represented as oblate ellipsoids with a smaller, more spherical component resting at the end of a larger, more elongated component. While contact binaries appear to be abundant in the near-Earth population, there are only a few published shape models for asteroids in this particular configuration. By combining the radar-derived shape model with optical light curves we determine a constant-period solution that fits all available data well. Using light-curve data alone we determine an upper limit for YORP of 8.5 × 10−8rad day−2.

Conclusions.The bifurcated shape of 1999 JV6 might be a result of two ellipsoidal components gently merging with each other, or a deformation of a rubble pile with a weak-tensile-strength core due to spin-up. The physical model of 1999 JV6 presented here will enable future studies of contact binary asteroid formation and evolution.
Research of a corrosion condition of an inventory of oil refineries on the example of complex works on monitoring of corrosion rate of process pipelines
Authors: Kiselev Oleg
Published: October 2019

In article the modern methods of corrosion monitoring which is one of the main tools for assessment of corrosion rate of processing equipment during its production activity are considered. Results of researches of corrosion processes and the analysis of corrosion rates of processing equipment of oil refineries are given, and the conclusion is also drawn on effectiveness of corrosion monitoring by a gravimetric method for monitoring of process of corrosion of an inventory in the conditions of aggressive environments.
Energy efficient station for cathodic protection of underground metalic pipelines using pulsed current modes
Authors: Shurayts Alexander , Maruhin Denis , Zubailov Hajiahmed , Tomashevskiy Yury
Published: October 2019

The perspectivity of protection against corrosion by pulsed current in terms of improving the energy efficiency of cathodic protection stations (CPS) are shown. The cathode polarization of the steel structure to the required protective potential values is provided by the station-controlled current parameters, as well as the transition from the direct current mode to the pulse mode and vice versa. A combined load model was implemented, including a traditional electric circuit for replacing a pipeline and a model based on fuzzy rules (FR), which connect the value of protective potential with the state of protective coatings of an underground steel structure, as well as the parameters of exposure to a corrosive environment. The control of the CPS modes using the FR system made it possible to optimize the station’s power consumption modes taking into account the variability of external environmental factors affecting the underground pipelines.
Improving the corrosion resistance of steels intended for use in seawater
Authors: Rodionova Irina , Amezhnov Andrey
Published: October 2019

The results of study of influence of the chemical composition of steel, the structural condition and contamination of nonmetallic inclusions of various types on its corrosion resistance in seawater are presented in the paper. The requirements for increased-corrosion-resistance steel for marine conditions and oilfield pipelines have been compared. It has been shown that a mandatory requirement for ensuring high corrosion resistance of steels is to ensure the purity of steels from unfavorable types of nonmetallic inclusions. It has also been shown that reducing the carbon content and alloying with nickel lead to an increase in the corrosion resistance of steel.
Power energy system sustainability performance evaluation and improving path of two regional economic circle in China
Authors: Yi Xiangyu , Li Jinchao , Wu Yunna , Chen Wenjun
Published: October 2019

The power energy system is the foundation of the sustainable development of the human society and has an important impact on the economic, environmental and security of human society development. This paper first establishes the input and output evaluation index system of sustainable development capability of power energy system from the economic, social, environmental and security dimensions, and then uses the CCR-DEA model considering the undesired output and Malmquist index to dynamically measure the sustainable development efficiency of the power system in the Beijing-Tianjin-Hebei and Yangtze River Delta from 2005 to 2016 and decompose the corresponding items. The future development situation was analyzed through scenario analysis. The results show that: (1) Beijing and Shanghai is better than that in other provinces and cities in the same region, showing an upward trend; (2) The changes in the efficiency of sustainable development of power energy systems in Beijing, Shanghai, Zhejiang and Anhui provinces are mainly caused by technical efficiency changes. That in Tianjin, Hebei and Jiangsu are from two aspects: technical efficiency and scale efficiency; (3) The sustainable development capacity of the power system in the Beijing-Tianjin-Hebei economic circle is higher than that of the Yangtze river delta power system, and this gap has the tendency of further widening according to the strategic development plan of the two regional power energy systems; (4) In the future, China's regional electric energy system development plans should draw on the energy development strategic plan of the Beijing-Tianjin-Hebei region, especially the Xiong'an National New District, so as to achieve coordinated and sustainable development of power energy systems in various regions.
Brain-Nutrients: Hirnstoffwechsel und Mikronährstoffe
Authors: Gröber Uwe , Kisters Klaus
Published: October 2019

Für die optimale Entwicklung und Funktion des Gehirns sowie die Neuroprotektion ist eine ausreichende Versorgung mit Vitamin D, EPA, DHA, Eisen, B-Vitaminen, antioxidativen Vitaminen und Carotinoiden notwendig. Die Ernährung von Kindern und Jugendlichen weicht häufig von den Empfehlungen ab, sodass sie oft mit den genannten Mikronährstoffen unterversorgt sind. Eine Ernährungsumstellung und ggf. die Supplementierung von Nährstoffen ist im Hinblick auf die kognitive Leistungsfähigkeit und die Gesunderhaltung des Gehirns empfehlenswert. Erfolg verspricht nur die regelmäßige und konsequente Einnahme über einen ausreichend langen Zeitraum.
Evaluation of feed restriction effects on mineral metabolism of intact male, female and castrated male goat kids
Authors: Santos Paula Fernanda Varella , Härter Carla Joice , Dias e Silva Nhayandra Christina , Leite Rafael Fernandes , de Miranda Figueiredo Fernanda Oliveira , Neto José Maurício Santos , de Rocha Fernandes Márcia Helena Machado , de Resende Kléber Tomás , de Almeida Teixeira Izabelle Auxiliadora Molina
Published: October 2019

The objective of the present study was to evaluate the effects of feed restriction on calcium (Ca), phosphorus (P) and magnesium metabolism in goat kids from 15 to 30 kg bodyweight, and to evaluate the role of sex in these processes. The study used a split plot design comprising three sex groups (intact males, castrated males and females), and the subplot comprised three levels of feed restriction (0% (ad libitum), 25% and 50%). Mineral intake and retention, mineral concentration in the blood, alkaline phosphatase activity and bone mineral density (BMD) of the femur were determined. The data were analysed as mixed models. Daily Ca, P and magnesium retention in the body decreased linearly with increasing feed restriction (P < 0.05). At 50% feed restriction, we observed a 22% reduction of alkaline phosphatase activity, and 9% and 7% reductions of Ca and P contents in blood serum. The BMD of females fed ad libitum was greater than castrated and intact males, whereas when subjected to 50% feed restriction, no differences in BMD were noted among the sexes (P < 0.01). Irrespective of feed restriction, females tended to retain less P in their bodies (P < 0.10) and tended to have the lowest P serum concentrations (P = 0.08). Our results indicated that only females showed decreased BMD under feed restriction; Ca, P and magnesium metabolism in prepubertal Saanen goat kids was mainly affected by feed restriction, whereas sex mainly affected the P metabolism.
Quantifying efficacy of feral pig (Sus scrofa) population management
Authors: Adams Peter J. , Fontaine Joseph B. , Huston Robert M. , Fleming Patricia A.
Published: October 2019

Abstract
ContextFeral pigs (Sus scrofa) are an increasing threat to agriculture and ecological communities globally. Although ground rooting is their most readily observable sign, feral pigs typically remain highly cryptic and their abundance and impacts are difficult to quantify.
AimsThe aim of the present study was to evaluate the effect of current feral pig population management practices (trapping, baiting, no feral pig management) on feral pig abundance and digging impacts, using a BACI (before–after control–impact) experimental design at a landscape scale.
MethodsA monitoring program was established to quantify both the abundance and digging impacts of feral pig populations within a temperate sclerophyll forest landscape using distance sampling. Transects were established across eight drinking water catchments where the whole catchment was the unit of replication for feral pig population management. Monitoring was carried out at 6-monthly intervals for 3 years, with no feral pig population management undertaken in the first year. In total, 367 feral pigs were trapped out of three catchments subject to trapping, and 26 were baited across two catchments subject to baiting with a commercial product (PIGOUT, Animal Control Technologies Australia, Melbourne, Vic., Australia). Three catchments were exempt from feral pig population management for the duration of this study.
Key resultsFeral pig density within the overall study site was estimated as 1.127pigskm–2, resulting in 4580diggingskm–2year–1. There was no significant difference in feral pig density estimates observed among population management treatments or the treatment×year interaction term. An overall decrease in feral pig density across all catchments was attributed to extreme temperature and drought conditions experienced during the study.
ConclusionsFeral pig populations demonstrate high resilience to current feral pig population management practices in the present study. The annual volume of soil disturbed by the numbers of feral pigs estimated across this study area is comparable to a commercial-scale resource extraction industry. We did not find significant differences in feral pig digging density among dominant vegetation types, but larger digs were associated with swamp vegetation.
ImplicationsCurrent levels of feral pig population management did not reduce pig densities across eight catchments in the northern jarrah forest; therefore, more intensive population management is needed.
Spectrum of flows on discrete pair of contours
Authors: Tatashev Alexander G. , Yashina Marina V.
Published: October 2019

We consider a deterministic discrete dynamical system, which is a contour network of Buslaev type. This system contains two contours. The ith contour contains Ni
cells, i = 1, 2. There is a cluster of particles on each contour moving in accordance with given rules. The clusters contain 1 ≤ M
1 < N
1 and 1 ≤ M
2 < N
2 particles respectively. There is no more than one particle in each cell at any time. There is a common point (node) of the contours. Particles cannot cross the node simultaneously. A set of repeating system states is called a spectral cycle. Average velocities of clusters correspond to spectral cycles. The set of spectral cycles and values of the average velocities have been found.
Research on variable probability assignment technique of genetic algorithm for WTA of ground target attacking
Authors: Fu Guangyuan , Wang Chao , Zhang Daqiao , Wang Ranhui , Zhang Shujuan , Tan Fei
Published: October 2019

The targets and the use of weapons are complicated on attacking ground target, Besides, the weapon-target assignment (WTA) research is extremely difficult and lacking. For a timely and rational WTA scheme can not only help to seize fleeting war opportunities, but also optimize the use of weapon resources to maximize the battlefield benefits with minimum costs, this article builds a mathematical model and uses genetic algorithm (GA) to find the optimal WTA result. But the algorithm is difficult to prepare better initial population because of the random assignment of variables which results in undesirable optimization results. To overcome the challenge in initializing GA, this article puts forward a variable probability assignment technique. This technique first uses feasible solutions to determine the probability distribution of the variable values, then, uses probability assignment mode to replace the stochastic uniform assignment mode to initialize variables, and produces the initial population individual close to the optimal individual with certainty. The simulation calculation shows that the improved GA can effectively solve the WTA problem of the large scale ground targets attacking with better performance.
Regional analysis on model validation with different metrics
Authors: Wu Danqing
Published: October 2019

Compared with the global analysis, the regional analysis can offer more comprehensive and more detail information with an input variable fixed in an interval. Existing validation metrics mostly focus on the global discrepancy between the observations and the computer models. To further measure the difference in detail, the concept of regional validation was proposed in this work. To make regional validation specific and easily understandable, two existing validation metrics-the area metric and the G metric were applied. The contribution to whole validation (CWV) metric was proposed to depict the relationship between the proposed regional validation and the initial whole scale validation. At last, an example was employed to demonstrate the rationality and necessity of the regional validation.
Numerical methods for the time fractional diffusion equation
Authors: Guo Chong , Zhao Fengqun
Published: October 2019

In this paper, a differential analog of the Caputo fractional derivative called the L2 − 1σ formula is considered. The time semi-discrete scheme of the time fractional diffusion equation is obtained by using the L2 − 1σ formula to discretize the time derivative. The Sinc-Collocation method and the Sinc-Galerkin method are used to discretize the spatial derivatives, and the numerical schemes of the time fractional diffusion equation are constructed. Finally, the validity of the numerical schemes of this paper is verified by numerical example.
The study on supply and demand of water resources in Alar city based on the system dynamics model
Authors: Liu Xijuan , Liu Yun
Published: October 2019

According to the status of water resources shortage in Alar, this paper establishes a system dynamics (SD) model for the water resources carrying capacity (WRCC) and analyzes the balance between water resources supply and demand. Three cases are designed to simulate the level of WRCC from 2010 to 2030. The total water demand and secondary product output value are chosen as the evaluation indices to study the WRCC in Alar. The results show that the carrying capacity of water resources in Alar cannot meet the demand of social economic development in recent years, and case 3 could effectively alleviate water scarcity. Based on the results, in order to guarantee sustainable utilization of water resources and social economy development, it is necessary to increase water saving policies and increase the introduction amount of surface water in the future.
Research on the optimization of logistics vehicle routing under multimode transportation strategy based on ant colony algorithm
Authors: Qi Haining , Liu Yanqiu , Xu Shida
Published: October 2019

The transformation of multiple transport tools which the multimode transportation process involves, and the split transportation brought by the third-party logistics makes the problem more complicated. At present, a large amount of research on the multimode transportation problem remains at the decision-making level, lacking quantitative comparative analysis of vehicle path combinatorial optimization problem. The common genetic algorithm adopts the method of generating an initial solution randomly, which will lead to a large number of infeasible solutions in the population and reduce the solving speed. In view of the above problems, this paper proposes using ant colony algorithm to solve the multimode transportation problem. The solution of ant colony algorithm is generated according to the pheromone concentration and the state transfer probability of nodes, so the feasibility of spatial connection is ensured in the generation stage of solution. The concept of virtual node is introduced to reduce the difficulty coefficient of the problem. Finally, an example is given to prove the validity of the proposed model and algorithm.
Complex networks derived from time series and its application in EEG-based emotion assessment with convolutional neural networks
Authors: Zhang Zelin , Xu Jinyu
Published: October 2019

Construction the complex network paradigm, it is evidenced a new tool for exploring the dynamic mechanism hiding in the time series data which is a trajectory of complex system. This method has been applied in various domains gradually, such as physics, engineering, medicine and economics. In this paper, a new method for network paradigm transforming based on separating with the isoprobability is proposed, then it is applied in EEG signal analysis. The measures of transformed networks from 62-electrods ESI NeuroScan platform were used to construct EEG map. A three-layer convolutional neural network with 15 input channels were built so as to implement EEG-based emotion assessment. By nine fold cross validation, the structure of the convolutional neural network is improved. The simulation shows that our approach is better than differential entropy features based method.
Study on electromagnetic dynamic tunability of composite structure based on plasma periodic structure loading frequency selective surface
Authors: Luo Qian , Hou Zhongyu
Published: October 2019

The plasma periodic structure has dynamic reconstruction characteristics having important practical significance in electromagnetic engineering applications. In this paper, a composite electromagnetic structure consisting of plasmas which are periodically arranged and frequency selective surface is proposed and researched. Based on the periodically arranged plasma columns, the frequency selective surface is introduced to study whether a photon-like effect will occur on EM waves propagation in the composite structure even a stronger dynamic tuning ability. The reflectivity between 1~2GHz and 8~12GHz was tested in a microwave dark room to study the influence of periodic plasma and frequency selective surface on incident electromagnetic waves with the free space method. A commercial electromagnetic software also was used to calculate the electric field at different frequency points, and study the mechanism of its interaction with electromagnetic waves.
Raman spectroscopic analysis of paddy rice infected by three pests and diseases common in Northeast Asia
Authors: Yue Xin , Tan Yong , Fan Wenzhong , Song Shaozhong , Ji Hongyu , Li Bingbing
Published: October 2019

Pests and diseases seriously affect the yield and economic benefits of growing rice, and the key to inhibiting rice’s pathogenesis is to find early identification of rice infection. The characteristic Raman spectrum of healthy leaves, and leaves infected with rice blast, paddy rice bakanae and infected by Chilo suppressalis (Walker) were tested by TriVista555CRS laser Raman spectrometer (900cm−1–1700cm−1). At the same integration time, compared with healthy plants, the Raman peak of infected plants not only changed significantly, but also the signal intensity decreased. The results show that there are clear Raman peaks at the three characteristic wavenumbers of 1002.87cm−1, 1156.5cm−1 and 1522.36cm−1. Especially in the leaves of rice blast, it was found that the degree of fungal infection affects the peak width at half height of the characteristic peak. The research shows that Raman spectroscopy provides an effective method for the early detection of rice pests and diseases which may have economic benefits.
Exact multiple inverses of the quadratic planar map
Authors: Huang Yu-Kun
Published: October 2019

We developed a method for exactly determining the multiple inverses of quadratic planar maps. The quadratic planar map was transformed through an affine transformation into its conjugate domain, where all inverses can be exactly determined, and transform the inverses back. We showed that for all quadratic planar maps with non-vanishing critical curves, except for two exceptional cases of the map with a degenerate critical curve, there exists at least one available transformation. For both exceptional cases and for those maps with vanishing critical curves, the inverses are determinable without any transformation. This result can be applied to the calculation of stable manifolds of the quadratic planar map. It may help us further understand the dynamics, the basins of attraction, and the bifurcations associated with the quadratic planar map under iteration.
Is Lagrangian weight crucial in the direct forcing immersed boundary method?
Authors: Zhou Kun , Ding Zhou , Sun Ke
Published: October 2019

Particle resolved direct numerical simulation (PR-DNS) is one of the most powerful research tools for particle laden flows. Among a few most popular PR-DNS methods, the direct forcing immersed boundary method (DF-IBM) has obtained great success and has been adopted in various simulations of rigid particulate flows. Within DF-IBM, Eulerian and Lagrangian frameworks are used to depict the continuum and dispersed phases, respectively. Interpolation between the two frameworks is accomplished through a discrete delta function. It is generally believed that a Lagrangian weight attached to each Lagrangian marker, which is distributed on a particle’s surface, needs to be carefully chosen. To be more specific, the Lagrangian weight is supposed to match the local Eulerian cell. The matching requirement is not trivial for non-uniform Eulerian mesh or irregular shaped particles. There are various methods developed to calculate the Lagrangian weight. Here, the Lagrangian weights in a few testing cases have been calculated following two intuitively “straightforward” methods. It turns out there are substantial discrepancies in the Lagrangian weights obtained from different methods. However, further numerical examples demonstrate that such discrepancies have negligible effects on the flow dynamics. So a natural question is raised: Is Lagrangian weight crucial in the direct forcing immersed boundary method? A negative answer to this question is suggested. More detailed analysis is provided in a forthcoming paper.
Research on XGboost academic forecasting and analysis modelling
Authors: Hu Ting , Song Ting
Published: October 2019

The analysis and evaluation of student achievement is an important part of teaching work and an important part of school routine management. Scientifically analysing and evaluating students’ academic achievements can not only enable teachers to accurately grasp the students’ learning status, but also enable students to understand their own learning situation, and also provide necessary analysis for teaching management and improving teaching. In order to evaluate students’ learning situation comprehensively, objectively and reasonably, this paper uses XGBoost algorithm to classify and evaluate students’ performance based on statistical analysis of basic data, and establishes a performance evaluation model. For the curriculum relevance, the student’ s performance data is statistically compiled according to the statistical knowledge. The subjective and objective structural entropy weight method is used to classify the characteristic importance results, and finally the relevant courses of the completed courses are obtained. For the results of the unfinished course using the completed course results, the XGBoost method is used to predict each student’ s grades.
An efficient EM algorithm for the mixture of negative binomial models
Authors: Huang Chunmao , Liu Xingwang , Yao Tianyuan , Wang Xiaoqiang
Published: October 2019

Overdispersion is a widespread phenomenon in most count data sets. The negative binomial distribution is commonly adopted to fit over-dispersed count data. On the other hand, the mixture model always plays an important role in unsupervised classification. However, when estimating the parameters in the mixture of negative binomial models, the typical generalized Expectation Maximization (EM) algorithm which involves additional iterative procedures in M-step increases computational time. Hence, there remains a need for an efficient algorithm that can speed up the procedure of parameter estimation. For this purpose, here we develop a novel EM algorithm that successfully avoids the typical numerical solution in M-step for the mixture of negative binomial models. We extend further this EM algorithm to the zero-inflated negative binomial model. In the simulation studies, we focus on the runtimes and the classification performance of our proposed algorithm implemented in the mixture of negative binomial model. We found that our proposed EM algorithm can reduce the runtime of maximum likelihood estimation effectively, while achieving the similar classification performance in comparison with the typical EM algorithm. The mixture of negative binomial model and the proposed EM algorithm finally illustrates their good performance of fitting the real earthquake count data.
Volatility spillover and co-movement among Chinese shipping sector stock index, oil futures price, ocean freight charge and exchange rate
Authors: Zhao Zitong , Tansuchat Roengchai
Published: October 2019

This study aims to analyze the co-movement and volatility spillover among four stock markets consist of Chinese shipping sector stock index, oil futures, shipping freight and currency market. We estimate dependence among these four markets using the multivariate copula model. Then we use the VAR model and impulse response function to investigate the volatility spillover among them. The empirical results show that the Gaussian copula is the most appropriate dependence mode as the AIC and BIC of this copula are the lowest when compared to other candidate copula models. The dependence correlation coefficients show a weak volatility dependence among these four markets. In addition, the results of the VAR suggest a spillover effect from shipping stock and oil to freight market.
Mangrove–diazotroph relationships at the root, tree and forest scales: diazotrophic communities create high soil nitrogenase activities in Rhizophora stylosa rhizospheres
Authors: Inoue Tomomi , Shimono Ayako , Akaji Yasuaki , Baba Shigeyuki , Takenaka Akio , Tuck Chan Hung
Published: October 2019

Background and Aims

The tidal flats on which mangrove plants grow tend to have low soil nitrogen contents because nitrogen-containing litter is repeatedly washed offshore by ebb tides. Under such circumstances, it is unclear how mangrove plants acquire the nitrogen required to support their vigorous growth. In the present work, chemical and biological characteristics of diazotrophy around mangrove plant roots were surveyed under natural conditions to elucidate mangrove–diazotroph relationships.

Methods

Soil nitrogenase activity of a representative mangrove plant, Rhizophora stylosa, which has a broad geographical distribution, was measured using the acetylene reduction assay at forest, tree and prop root scales. In addition, diazotrophic community composition was compared between rhizosphere and bulk soil based on sequencing of nifH genes.

Key Results

Soil nitrogenase activity was high near prop roots, and this pattern was enhanced as soil live root content increased. At the forest scale, we observed high soil nitrogenase activity (acetylene-reducing activity) inside the forest (the highest value was 90.9 µmol C2H2 min−1 cm−3, average 46.8 ± 18.2 µmol C2H2 min−1 cm−3). Rates decreased sharply from the forest to the tidal flat (range 1.2–22.2 µmol C2H2 min−1 cm−3, average 7.9 ± 4.5 µmol C2H2 min−1 cm−3). The nifH operational taxonomic unit composition differed significantly among forest and tree rhizospheres and the bulk soil (P < 0.0001).

Conclusions

Our results suggest that the accumulation of diazotrophs around R. stylosa mangrove trees enhances the supply of biologically fixed nitrogen to the mangrove roots. This supply is especially important when the soil naturally contains little nitrogen. This nitrogen acquisition system may be a key process that explains the high productivity of mangrove ecosystems.
Cardiac perfusion, structure, and function in type 2 diabetes mellitus with and without diabetic complications
Authors: Sørensen Martin Heyn , Bojer Annemie Stege , Broadbent David Andrew , Plein Sven , Madsen Per Lav , Gæde Peter
Published: October 2019

Aims

Coronary microvascular disease (CMD) is a known complication in type 2 diabetes mellitus (T2DM). We examined the relationship between diabetic complications, left ventricular (LV) function and structure and myocardial perfusion reserve (MPR) as indicators of CMD in patients with T2DM and control subjects.

Methods and results

This was a cross-sectional study of 193 patients with T2DM and 25 controls subjects. Patients were grouped as uncomplicated diabetes (n = 71) and diabetes with complications (albuminuria, retinopathy, and autonomic neuropathy). LV structure, function, adenosine stress, and rest myocardial perfusion were evaluated by cardiovascular magnetic resonance. Echocardiography was used to evaluate diastolic function. Patients with uncomplicated T2DM did not have significantly different LV mass and E/e* but decreased MPR (3.8 ± 1.0 vs. 5.1 ± 1.5, P < 0.05) compared with controls. T2DM patients with albuminuria and retinopathy had decreased MPR (albuminuria: 2.4 ± 0.9 and retinopathy 2.6 ± 0.7 vs. 3.8 ± 1.0, P < 0.05 for both) compared with uncomplicated T2DM patients, along with significantly higher LV mass (149 ± 39 and 147 ± 40 vs. 126 ± 33 g, P < 0.05) and E/e* (8.3 ± 2.8 and 8.1 ± 2.2 vs. 7.0 ± 2.5, P < 0.05). When entered in a multiple regression model, reduced MPR was associated with increasing E/e* and albuminuria and retinopathy were associated with reduced MPR.

Conclusions

Patients with uncomplicated T2DM have reduced MPR compared with control subjects, despite equivalent LV mass and E/e*. T2DM patients with albuminuria or retinopathy have reduced MPR and increased LV mass and E/e* compared with patients with uncomplicated T2DM. E/e* and MPR are significantly associated after adjustment for age, hypertension, and LV mass, suggesting a link between CMD and cardiac diastolic function.

Clinical trial registration

https://www.clinicaltrials.org. Unique identifier: NCT02684331
Cardiogenic shock triggered by phaeochromocytoma crisis after an oral glucose tolerance test: a case report
Authors: Shahim Bahira , Faxén Ulrika Ljung , Stern Rebecka , Freyschuss Anna
Published: October 2019

Background

Phaeochromocytomas are rare catecholamine-producing tumours which typically present with comparatively benign symptoms such as headache, palpitations, sweating, hypertension, and insulin resistance. In rare cases, severe cardiac manifestations have been reported. We describe a patient who developed severe hypoglycaemia after an oral glucose tolerance test (OGTT), potentially triggering a phaeochromocytoma crisis and cardiogenic shock. To the best of our knowledge, only four other cases of hypoglycaemia after OGTT have been reported in patients with phaeochromocytoma, of which none developed a phaeochromocytoma crisis.

Case summary

A 53-year-old woman with hypertension, dyslipidaemia, and prediabetes presented to the Emergency Department with hypoxia, hyperglycaemia, lactic acidosis, severe left ventricular dysfunction, and pulmonary oedema followed by cardiogenic shock. Onset of symptoms was only few hours after an OGTT during which she had developed severe transient hypoglycaemia. Angiography was performed due to elevated troponin levels and showed a midventricular contraction pattern typical of takotsubo. This was subsequently confirmed by cardiac magnetic resonance imaging. The patient’s condition improved during the first 36 h and she was discharged home on Day 7. A positive catecholamine test prompted readmission to the Endocrinology Unit, where computer tomography confirmed the diagnosis of phaeochromocytoma. An adrenalectomy was performed, and the diagnosis was verified histopathologically.

Discussion

The possibility of a phaeochromocytoma must be considered as a potential triggering factor in patients presenting with takotsubo cardiomyopathy, in particular, when blood glucose levels fluctuate between severe hypo- and hyperglycaemia.
Lessepsian fish invasion in Mediterranean marine protected areas: a risk assessment under climate change scenarios
Authors: D’Amen M , Azzurro E
Published: October 2019

Mediterranean marine protected areas (MPAs), designed to achieve long-term nature conservation, are progressively conquered by invasive species of tropical origin, posing novel challenges for managers and policymakers of the 21st century. In this study, we assessed the vulnerability of 142 coastal Mediterranean MPAs to nine of the most invasive fishes under current and future climatic conditions. We predicted invasive species’ habitat suitability using an ensemble modelling approach, calibrating models on the entire distribution of the species. We categorized three risk levels for Mediterranean MPAs, based on the assumption that more suitable habitat conditions make protected areas more prone to invasion. Future projections forecasted an increase of suitable areas for all considered species in the Mediterranean basin. In the Levantine Sea, almost all MPAs are at high risk of invasion by the considered species both in the current and future scenarios. MPAs located in the other Mediterranean sectors have currently a low suitability for most invasive species, but their risk level will increase overall by 2050, especially in the South Adriatic Sea and off South Western Italy. By identifying spatial priorities in a global change context, we fill critical information gaps on the vulnerability of MPAs to the future expansion of warm-water invaders.