Pattern changes and early risk warning of Spartina alterniflora invasion:a study of mangrove-dominated wetlands in northeastern Fujian,China

The exotic saltmarsh cordgrass,Spartina alterniflora(Loisel)Peterson&Saarela,is one of the important causes for the extensive destruction of mangroves in China due to its invasive nature.The species has rapidly spread wildly across coastal wetlands,challenging resource managers for control of its further spread.An investigation of S.alterniflora invasion and associated ecological risk is urgent in China's coastal wetlands.In this study,an ecological risk invasive index system was developed based on the Driving Force-Pressure-State-Impact-Response framework.Predictions were made of'warning degrees':zero warning and light,moderate,strong,and extreme warning,by developing a back propagation(BP)artificial neural network model for coastal wetlands in eastern Fujian Province.Our results suggest that S.alterniflora mainly has invaded Kandelia candel beaches and farmlands with clustered distributions.An early warning indicator system assessed the ecological risk of the invasion and showed a ladder-like distribution from high to low extending from the urban area in the central inland region with changes spread to adjacent areas.Areas of light warning and extreme warning accounted for43%and 7%,respectively,suggesting the BP neural network model is reliable prediction of the ecological risk of S.alterniflora invasion.The model predicts that distribution pattern of this invasive species will change little in the next 10 years.However,the invaded patches will become relatively more concentrated without warning predicted.We suggest that human factors such as land use activities may partially determine changes in warning degree.Our results emphasize that an early warning system for S.alterniflora invasion in China's eastern coastal wetlands is significant,and comprehensive control measures are needed,particularly for K.candel beach.

Dynamic Case Retrieval Method With Subjective Preferences and Objective Information for Emergency Decision Making

Case-based reasoning(CBR) is one of the best methods for generating an effective solution in an emergency. In recent years, some methods for generating emergency alternatives have been included in practical CBR applications, but there have been no in-depth studies of these processes. In this study,we propose a new method for dynamic case retrieval with subjective preferences and objective information, which considers the personal preferences of the decision makers and changes in the attributes of the emergency as the situation develops. First,we present a formula for calculating the case similarity and changing trends in the case considered, where similar cases are obtained. Next, we describe a method for measuring the overall assessment value with respect to similar historical cases, which is obtained by aggregating the case similarity, the utility case similarity, the first response time, and the implementation effect.The subjective preferences and objective information are also integrated in the decision-making process. Finally, we present a case study based on the emergency response to a fire in a highrise building, which illustrates the applicability and feasibility of the proposed method.

Enhancing carrier transport in flexible CZTSSe solar cells via doping Li strategy

The passivation of non-radiative states and inhibition of band tailings are desirable for improving the open-circuit voltage(V_(oc))of CZTSSe thin-film solar cells.Recently,alkali metal doping has been investigated to passivate defects in CZTSSe films.Herein,we investigate Li doping effects by applying Li OH into CZTSSe precursor solutions,and verify that carrier transport is enhanced in the CZTSSe solar cells.Systematic characterizations demonstrate that Li doping can effectively passivate non-radiative recombination centers and reduce band tailings of the CZTSSe films,leading to the decrease in total defect density and the increase in separation distance between donor and acceptor.Fewer free carriers are trapped in the band tail states,which speeds up carrier transport and reduces the probability of deep-level defects capturing carriers.The charge recombination lifetime is about twice as long as that of the undoped CZTSSe device,implying the heterojunction interface recombination is also inhibited.Besides,Li doping can increase carrier concentration and enhance build-in voltage,leading to a better carrier collection.By adjusting the Li/(Li+Cu)ratio to 18%,the solar cell efficiency is increased significantly to 9.68%with the fill factor(FF)of 65.94%,which is the highest FF reported so far for the flexible CZTSSe solar cells.The increased efficiency is mainly attributed to the reduction of V_(oc)deficit and the improved CZTSSe/Cd S junction quality.These results open up a simple route to passivate non-radiative states and reduce the band tailings of the CZTSSe films and improve the efficiency of the flexible CZTSSe solar cells.

The First Principle Study on the Rectification of Molecular Junctions Based on the Alkyl-chain-modified Phenyl Benzothiophene Derivative

Using density functional theory（DFT） combined with nonequilibrium Green＇s function investigates the electron-transport properties of several molecular junctions based on the PBTDT-CH=NH molecule, which is modified by one to four alkyl groups forming PBTDT-（CH2）nCH=NH. The electronic structures of the isolated molecules（thiol-ended PBTDT-（CH2）nCH=N） have been investigated before the electron-transport calculations are performed. The asymmetric current-voltage characteristics have been obtained for the molecular junctions. Rectifying performance of Au/S-PBTDT-CH=N-S/Au molecular junction can be regulated by introducing alkyl chain. The N3 molecular junction exhibits the best rectifying effect. Its maximum rectifying ratio is 878, which is 80 times more than that of the molecular junction based on the original N molecular junction. The current-voltage（I-V） curves of all the sandwich systems in this work are illustrated by transmission spectra and molecular projection density analysis.

Triple bottom-line consideration of sustainable plant disease management:From economic,sociological and ecological perspectives

Plant disease management plays an important role in achieving the sustainable development goals of the United Nations(UN)such as food security,human health,socio-economic improvement,resource conservation and ecological resilience.However,technologies available are often limited due to different interests between producers and society and lacks of proper understanding of economic thresholds and the complex interactions among ecology,productivity and profitability.A comprehensive synergy and conflict evaluation of economic,sociological and ecological effects with technologies,productions and evolutionary principles as main components should be used to guide sustainable disease management that aims to mitigate crop and economic losses in the short term while maintaining functional farm ecosystem in the long term.Consequently,there should be an increased emphasis on technology development,public education and information exchange among governments,researchers,producers and consumers to broaden the options for disease management in the future.

A 9% efficiency of flexible Mo-foil-based Cu2ZnSn(S,Se)4 solar cells by improving CdS buffer layer and heterojunction interface

Flexible Cu2ZnSn(S,Se)4(CZTSSe)solar cells show great potential applications due to low-cost,nontoxicity,and stability.The device performances under an especial open circuit voltage(VOC)are limited by the defect recombination of CZTSSe/CdS heterojunction interface.We improve the deposition technique to obtain compact CdS layers without any pinholes for flexible CZTSSe solar cells on Mo foils.The efficiency of the device is improved from 5.7%to 6.86%by highquality junction interface.Furthermore,aiming at the S loss of CdS film,the S source concentration in deposition process is investigated to passivate the defects and improve the CdS film quality.The flexible Mo-foil-based CZTSSe solar cells are obtained to possess a 9.05%efficiency with a VOC of 0.44 V at an optimized S source concentration of 0.68 mol/L.Systematic physical measurements indicate that the S source control can effectively suppress the interface recombination and reduce the VOCdeficit.For the CZTSSe device bending characteristics,the device efficiency is almost constant after1000 bends,manifesting that the CZTSSe device has an excellent mechanical flexibility.The effective improvement strategy of CdS deposition is expected to provide a new perspective for promoting the conversion efficiency of CZTSSe solar cells.

Quantum Hierarchical Agglomerative Clustering Based on One Dimension Discrete Quantum Walk with Single-Point Phase Defects

As an important branch of machine learning,clustering analysis is widely used in some fields,e.g.,image pattern recognition,social network analysis,information security,and so on.In this paper,we consider the designing of clustering algorithm in quantum scenario,and propose a quantum hierarchical agglomerative clustering algorithm,which is based on one dimension discrete quantum walk with single-point phase defects.In the proposed algorithm,two nonclassical characters of this kind of quantum walk,localization and ballistic effects,are exploited.At first,each data point is viewed as a particle and performed this kind of quantum walk with a parameter,which is determined by its neighbors.After that,the particles are measured in a calculation basis.In terms of the measurement result,every attribute value of the corresponding data point is modified appropriately.In this way,each data point interacts with its neighbors and moves toward a certain center point.At last,this process is repeated several times until similar data points cluster together and form distinct classes.Simulation experiments on the synthetic and real world data demonstrate the effectiveness of the presented algorithm.Compared with some classical algorithms,the proposed algorithm achieves better clustering results.Moreover,combining quantum cluster assignment method,the presented algorithm can speed up the calculating velocity.

Analysis of Effect of Zn(O,S) Buffer Layer Properties on CZTS Solar Cell Performance Using AMPS

The Cu2ZnSnS4 （CZTS）-based solar cell is numerically simulated by a one-dimensional solar cell simulation soft- ware analysis of microelectronic and photonic structures （AMPS-1D）. The device structure used in the simulation is Al/ZnO：Al/nZn（O,S）/pCZTS/Mo. The primary motivation of this simulation work is to optimize the composition in the ZnO1-xSx buffer layer, which would yield higher conversion efficiency. By varying S/（S＋O） ratio x, the conduction band offset （CBO） at CZTS/Zn（O,S） interface can range from -0.23 eV to 1.06eV if the full range of the ratio is considered. The optimal CBO of 0.23eV can be achieved when the ZnO1-xSx buffer has an S/（S＋O） ratio of 0.6. The solar cell efficiency first increases with increasing sulfur content and then decreases abruptly for x〉 0.6, which reaches the highest value of 17.55% by our proposed optimal sulfur content x= 0.6. Our results provide guidance in dealing with the ZnO1-xSx buffer layer deposition for high efficiency CZTS solar cells.

Speculations on Achieving ＂Self - employment＂ in the Internet Economy

The advent of the universal Internet Era provides a new platform for employment and entrepreneurship,highlighting the new trend of"self-employment".It is necessary for all departments of the government to cooperate in employment and entrepreneurship and carry out coordinated planning in the huge project of employment.The government is required to improve policies and laws,establish market-oriented talent development system and public system,promote new development of entrepreneurship and employment in the Internet economy,alleviate China's current severe employment situation,solve the problem of employment and entrepreneurship,and eventually find a new economic growth point.

Supersaturating Silicon with Titanium by Continuous-Wave Laser Irradiation of Sputtered Titanium Film on Silicon

A method of magnetron sputtering followed by continuous-wave （cw） laser irradiation is developed to prepare crystalline silicon supersaturated with titanium. The irradiation of single crystalline Si samples sputtered with a thin layer of Ti is carried out under the 1064nm ew laser in a specially designed home-made facility. The thickness of the Si layer, within which the concentration of Ti surpasses the Mott limit, reaches 365 nm and the maximum concentration of Ti reaches 1.83 × 1021 cm-3. The crystalline structure of the Si samples is kept unchanged after cw laser irradiation. These results show that the current method can be an emcient way to obtain an intermediate band semiconductor material for solar cells.

CHARACTERIZATION OF MODULAR FROBENIUS GROUPS OF SPECIAL TYPE

In this article, we first investigate the properties of modular Frobenius groups. Then, we consider the case that G＇ is a minimal normal subgroup of a modular Frobenius group G. We give the complete classification of G when G＇ as a modular Frobenius kernel has no more than four conjugacy classes in G.

A New Mixed-metal Monophosphate:Ba2Bi2Co(PO4)4

A new member of mixed-metal Ba2Bi2M-Ⅱ（PO4）4 monophosphate, namely Ba2Bi2Co（PO4）4, was synthesized by solid state method and characterized by X-ray single-crystal diffraction and powder diffraction for the first time. It crystallizes in the orthorhombic system with space group Pnma（No. 62） and features a 3D architecture built up of adjacent zig-zag linear structures of [CoP4O（16）]∞ along [100], and further connected by [Bi2O（11）] dimers to form a 3D framework, where the Ba2＋ are located in the free space. The stereochemical activity of the Bi3＋ lone pair has also been discussed. The result of magnetic property measurement confirms the antiferromagnetic property of Ba2Bi2Co（PO4）4.

Investigating College Students’ Diet and Physical Activity Behaviors Regarding Non-Communicable Diseases Prevention in China

We aimed to investigate if college students’ dietary and physical activity adhered to the Chinese Dietary Guidelines, the Composing Editorial Board of Physical Activity Guidelines, and WHO recommendation for NCDs prevention. Methods: A 3-day (2 weekdays and 1 weekend day) 24-hour (24-HRs) dietary recall was conducted to record details of participants’ food consumption. One-way analysis of variance (ANOVA) was applied to examine the influence of the identified demographic variables (including BMI, gender, major, family monthly income, and place of household registration) on the 8 food groups’ consumption. We analyzed the effect of the various demographic variables on sodium intake by the student’s t-test. The questionnaire, International Physical Activity Questionnaire (IPAQ)-Short Form, was utilized to assess participants’ physical activity (PA) level. The Wilcoxon-Mann-Whitney was applied to analyze participants’ physical activity. Results: Our research indicated participants consumed much fewer fruits and vegetables and excessive meats on average for both males and females regarding NCDs prevention. Conclusion: Participants’ dietary intake did not comply with the Chinese Dietary Guide-lines recommendation for chronic diseases prevention. Nutrition knowledge and health education are needed for college students. .

Synthesis,Single-crystal Structure,and Computational Studies of a Yavapaiite Structure Compound:Pb(Sb0.5Fe0.5)(PO4)2

The single crystals and powder of a Yavapaiite Structure phosphate,namely,PbSb0.5Fe0.5（PO4）2,were synthesized by solid state method and characterized by X-ray single-crystal diffraction and powder diffraction.The title compound crystallizes in the monoclinic system,space group C2/c（No.15） with a = 16.716（4）,b = 5.186（7）,c = 8.130（2）A,β = 114.93（6）°,Z = 4,R（I 〉 2s（I）） = 0.0430,R indices（all data） = 0.0460,and T = 293（2） K.The title compound belongs to the Yavapaiite Structure A^（Ⅱ）M^（Ⅳ）（PO4）2 compounds,and the Sb1 atom and Fe1 atoms occupy the same site（M） and their occupancy factors are refined to be 0.5 and 0.5 having a sum occupancy factor of 1.0.Its structure consists of [M（PO）4]n^2n- layers running parallel to the（b,c） plane built up of cornerconnected MO6 octahedra and PO4 tetrahedra.Additionally,the calculations of energy band structure,and density of states have been performed with the density functional theory method.The studies of computational calculation and UV experimental results show that the new compound is an indirect band-gap insulator.

Phonon-blockade-based multiple-photon bundle emission in a quadratically coupled optomechanical system

We propose a scheme to realize antibunched multiple-photon bundles based on phonon blockade in a quadratically coupled optomechanical system.Through adjusting the detunings to match the conditions of phonon blockade in the photon sidebands,we establish super-Rabi oscillation between zero-photon state and multiple-photon states with adjustable super-Rabi frequencies under appropriate single-phonon resonant conditions.Taking the system dissipation into account,we numerically calculate the standard and generalized second-order functions of the cavity mode as well as the quantum trajectories of the state populations with Monte Carlo simulation to confirm that the emitted photons form antibunched multiple-photon bundles.Interestingly,the desirable n-photon states are reconstructed after a direct phonon emission based on phonon blockade,and thus the single-phonon emission heralds the cascade emission of n-photon bundles.Our proposal shows that the optomechanical system can simultaneously behave as antibunched multiple-photon emitter and single-phonon gun.Such a nonclassical source could have potential applications in quantum information science.

A Dynamic Emergency Decision-Making Method Based on Group Decision Making with Uncertainty Information

In emergency decision making(EDM),it is necessary to generate an effective alternative quickly.Case-based reasoning(CBR)has been applied to EDM;however,choosing the most suitable case from a set of similar cases after case retrieval remains challenging.This study proposes a dynamic method based on case retrieval and group decision making(GDM),called dynamic casebased reasoning group decision making(CBRGDM),for emergency alternative generation.In the proposed method,first,similar historical cases are identified through case similarity measurement.Then,evaluation information provided by group decision makers for similar cases is aggregated based on regret theory,and comprehensive perceived utilities for the similar cases are obtained.Finally,the most suitable historical case is obtained from the case similarities and the comprehensive perceived utilities for similar historical cases.The method is then applied to an example of a gas explosion in a coal company in China.The results show that the proposed method is feasible and effective in EDM.The advantages of the proposed method are verified based on comparisons with existing methods.In particular,dynamic CBRGDM can adjust the emergency alternative according to changing emergencies.The results of application of dynamic CBRGDM to a gas explosion and comparison with existing methods verify its feasibility and practicability.

A hybrid genetic algorithm for multi-objective flexible job shop scheduling problem considering transportation time

Purpose–Flexible job-shop scheduling is significant for different manufacturing industries nowadays.Moreover,consideration of transportation time during scheduling makes it more practical and useful.The purpose of this paper is to investigate multi-objective flexible job-shop scheduling problem(MOFJSP)considering transportation time.Design/methodology/approach–A hybrid genetic algorithm(GA)approach is integrated with simulated annealing to solve the MOFJSP considering transportation time,and an external elitism memory library is employed as a knowledge library to direct GA search into the region of better performance.Findings–The performance of the proposed algorithm is tested on different MOFJSP taken from literature.Experimental results show that proposed algorithm performs better than the original GA in terms of quality of solution and distribution of the solution,especially when the number of jobs and the flexibility of the machine increase.Originality/value–Most of existing studies have not considered the transportation time during scheduling of jobs.The transportation time is significantly desired to be included in the FJSP when the time of transportation of jobs has significant impact on the completion time of jobs.Meanwhile,GA is one of primary algorithms extensively used to address MOFJSP in literature.However,to solve the MOFJSP,the original GA has a possibility to get a premature convergence and it has a slow convergence speed.To overcome these problems,a new hybrid GA is developed in this paper.

Experiment on Seismic Performance of Frame-Masonry Horizontal Hybrid Structure Based on Shaking Table Test

Frame-masonry horizontal hybrid structure is a new type of self-built residence in the rural areas of Fujian Province in recent years. A shaking table test for 1/2 scale model is carried out on the basis of one representative rural structure, and the dynamic characteristics and seismic responses of this experimental model are measured. As a supplement, the finite element model of the prototype structure is built by ANSYS software,and simulation and test results are contrasted and analyzed. The results show that according to this structure,the beam-column joint of the frame part has stress concentration and the destruction pattern of the masonry part is similar to brick-masonry structure. There are obvious differences in lateral stiffness of each floor and direction,and the mass center does not coincide with the stiffness center, which can lead to excessive torsion and story drift of this structure under earthquakes of a certain intensity. Because of poor construction quality, unfavorable structural measures and irrational structural system in present rural areas, there is a potential safety threat with this type of structures in highly seismic region. Some suggestions for strengthening and retrofitting frame-masonry horizontal hybrid structures are pointed out.

Some Generalized Single Valued Neutrosophic Linguistic Operators and Their Application to Multiple Attribute Group Decision Making

This paper proposes a group decision making method based on entropy of neutrosophic linguistic sets and generalized single valued neutrosophic linguistic operators. This method is applied to solve the multiple attribute group decision making problems under single valued neutrosophic liguistic environment, in which the attribute weights are completely unknown. First, the attribute weights are obtained by using the entropy of neutrosophic linguistic sets. Then three generalized single valued neutrosophic linguistic operators are introduced, including the generalized single valued neutrosophic linguistic weighted averaging(GSVNLWA) operator, the generalized single valued neutrosophic linguistic ordered weighted averaging(GSVNLOWA) operator and the generalized single valued neutrosophic linguistic hybrid averaging(GSVNLHA) operator, and the GSVNLWA and GSVNLHA operators are used to aggregate information. Furthermore, similarity measure based on single valued neutrosophic linguistic numbers is defined and used to sort the alternatives and obtain the best alternative. Finally,an illustrative example is given to demonstrate the feasibility and effectiveness of the developed method.

A high-precision system of fiber Bragg grating temperature sensing demodulation based on light power detection

A system of fiber Bragg grating(FBG)temperature sensing demodulation based on light power detection is proposed in this paper.Compared with the traditional demodulation method based on wavelength scanning,light power detection is more direct and avoids the use of spectrometer.Moreover,the light power in the system is converted into the electrical signal by the receiver optical subassembly(ROSA)and converted to the digital signal.The micro controller unit(MCU)processes the digital signal to realize the real-time temperature monitoring,which avoids the use of optical power meter(OPM).With the advantages of simple structure and low cost,the system is portable and practical.The experimental results show that the linearity coefficients R-square between light power and the sampling voltage are 0.99908 and 0.99893 in the temperature range from 10°C to 85°C,respectively.According to the results,the proved sensor has a repeatability error of 1%,a linearity error of 1.35%,and a hysteresis error of 0.7%,which indicates that the system is of high stability and high precision.The experimental results are consistent with the theory,which verifies the system’s feasibility.