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Let $$T_{n}$$ be an arc-colored tournament of order n. The maximum monochromatic indegree $$\varDelta ^{-mon}(T_{n})$$ (resp. outdegree $$\varDelta ^{+mon}(T_{n})$$ ) of $$T_{n}$$ is the maximum number of in-arcs (resp. out-arcs) of a same color incident to a vertex of $$T_{n}$$ . The irregularity $$i(T_{n})$$ of $$T_{n}$$ is the maximum difference between the indegree and outdegree of a vertex of $$T_{n}$$ . A subdigraph H of an arc-colored digraph D is called rainbow if each pair of arcs in H have distinct colors. In this paper, we show that each vertex v in an arc-colored tournament $$T_{n}$$ with $$\varDelta ^{-mon}(T_n)\le \varDelta ^{+mon}(T_n)$$ is contained in at least $$\frac{\delta (v)(n-\delta (v)-i(T_n))}{2}-[\varDelta ^{-mon}(T_{n})(n-1)+\varDelta ^{+mon}(T_{n})d^+(v)]$$ rainbow triangles, where $$\delta (v)=\min \{d^+(v), d^-(v)\}$$ . We also give some maximum monochromatic degree conditions for $$T_{n}$$ to contain rainbow triangles, and to contain rainbow triangles passing through a given vertex. Finally, we present some examples showing that some of the conditions in our results are best possible.

Economic development has led to a rapid increase in urban water consumption. The number of cities with water shortages nationwide is increasing. The establishment of a water resource circulation system is conducive to solving the urban water shortage. This study aims to investigate the restoration of the urban water environment landscape system and the integration of SWMM technology in cities with scarce water resources. For this objective, the meteorological situation of a city with water shortage in central China was used to establish the surface water hydrological model of Teaneck Creek. By establishing a data collection system at each meteorological point of the city, the USEPA SWMM model was implemented to simulate the movement of the urban sub-base system. The relationship model between the surface water flow and groundwater flow was established, and then the relationship between vegetation and soil was determined to formulate a plan for the restoration of a benign and environmentally friendly urban water environment landscape system. The established model can solve the urban water shortage problem. The results showed that the developed model was increased the utilization rate of water resources by about 20% and the urban greening rate by about 15%. The system will bring China a sustainable and eco-friendly urbanization process, which is of guiding significance for the production and development of cities with water shortages in China.

Purpose This study aims to manufacture cotton fabric with thermal regulation performance by using the composite phase change material (CPCM) prepared by coating paraffin doped with expanded graphite (EG), and the thermal effect of the fabric material was evaluated and characterized. Design/methodology/approach EG/paraffin CPCM with shape stability and enhanced thermal conductivity were prepared by the impregnation method and then finished on the surface of cotton fabric with coating technology. The microstructure, crystal structure, chemical composition, latent heat property and thermal conductivity were analyzed by scanning electron microscope, x-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimeter and thermal constant analyzer. The photo-thermal effect of the coated fabric was studied by a thermal infrared imager. Findings CPCM prepared with a mass ratio of EG to paraffin of 1:8 showed excellent shape stability and low paraffin leakage rate. The latent heat of the CPCM was 51.6201 J/g and the thermal conductivity coefficient was increased by 11.4 times compared with the mixed paraffin. After the CPCM was coated on the surface of the cotton fabric, the light-to-heat conversion rate of the C-EG/PA3 sample was improved by 86.32% compared with the original fabric. In addition, the coated fabric showed excellent thermal stability and heat storage performance in the thermal cycling test. Research limitations/implications EG can improve the shape stability and thermal conductivity of paraffin but will reduce the latent heat energy. Practical implications The method developed provided a simple and practical solution to improving the thermal regulation performance of fabrics. Originality/value Combining paraffin wax with fabrics in a composite way is innovative and has certain applicability in improving the thermal properties of fabrics.

Clustering data with both numeric and categorical attributes is of great importance as such data are ubiquitous in real-world problems. Multi-view learning approaches have proven to be more effective and having better generalisation ability compared to single-view learning in many problems. However, most of the existing clustering algorithms developed for mixed numeric and categorical data are single-view. In this research, we propose a novel multi-view clustering algorithm based on the k-prototypes (which we term Multi-view K-Prototypes) for clustering mixed data. To the best of our knowledge, our proposed Multi-view K-Prototypes is the first multi-view version of the well-known k-prototypes algorithm. To cluster the mixed data over multiple views, we present a novel representation prototype of cluster centres in the scenario of multiple views, and we also devise formulas for updating the cluster centres over each view. Then we propose the concept of consensus cluster centres to output the final clustering result. Finally, we carried out a series of experiments on four benchmark datasets to assess the performance of the proposed Multi-view K-Prototypes clustering. Experimental results show that the Multi-view K-Prototypes algorithm outperforms the seven state-of-the-art algorithms in most cases.

Recycling methods will be essential for the future circular economy in the context of declining natural resources. Nanomaterials are promising adsorbents to recover rare earth elements from wastewater, yet the practical application of nanomaterials is limited by spontaneous agglomeration, easy collapse of structures and the difficulty in collecting nanomaterials after adsorption. To solve these issues, we prepared a polyurethane sponge-supported titanium phosphate with graphene oxide, abbreviated as GO@TiP-Sponge, by in situ precipitation. GO@TiP-Sponge was characterized by X-ray diffraction, scanning electron microscope, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy, and tested for the removal and recovery of trace dysprosium Dy(III), a rare-earth element, in water using batch experiments. Results show that the GO@TiP-Sponge showed an excellent affinity for dysprosium with theoretical capacity reaching 576.17 mg/g according to the Langmuir model. Half-equilibrium was reached in 2.5 min according to a pseudo-second-order model. GO@TiP-Sponge also displayed an adsorption ability for a wide range of pH and salinity. Such performance is explained by strong binding of phosphate with Dy(III), enhanced surface area induced by graphene oxide and less aggregation from the spongy structure. The main adsorption mechanism involves electrostatic interaction.

This article describes a new method of urban pluvial flood modeling by coupling the 1D storm water management model (SWMM) and the 2D flood inundation model (ECNU Flood-Urban). The SWMM modeling results (the overflow of the manholes) are used as the input boundary condition of the ECNU Flood-Urban model to simulate the rainfall–runoff processes in an urban environment. The analysis is applied to the central business district of East Nanjing Road in downtown Shanghai, considering 5-, 10-, 20-, 50-, and 100-year return period rainfall scenarios. The results show that node overflow, water depth, and inundation area increase proportionately with the growing return periods. Water depths are mostly predicted to be shallow and surface flows generally occur in the urban road network due to its low-lying nature. The simulation result of the coupled model proves to be reliable and suggests that urban surface water flooding could be accurately simulated by using this methodology. Adaptation measures (upgrading of the urban drainage system) can then be targeted at specific locations with significant overflow and flooding.

The physicochemical and catalytic properties of La0.8Ce0.2Mn1–xFexO3 were studied by NO + CO activity tests and a series of characterizations. Improvement of catalytic activity for the La0.8Ce0.2Mn...

Maintaining high crop yield and meanwhile reducing the risk of environmental pollution are of paramount importance for food security and sustainability. The aims of this study were (i) quantify soil NO3− -N buffer capacity under wheat-maize cropping system in Northern China, and (ii) establish agronomic optimum and environmentally safe N rates to guide N recommendation for the region. We compiled data of 76 sets of wheat and 73 sets of maize experiments spanning about 20 years, where N rate experiments conducted and soil NO3− -N content were measured immediately after crop harvest under conventional practice. By applying linear-plateau and plateau-linear models, we computed the soil NO3− -N buffer capacity, agronomic optimum N rate and environmentally safe N rates. Soil NO3− -N buffer capacity ranged from 10 to 221 kg ha−1 for wheat season and from 14 to 212 kg ha−1 for maize season, which were mostly less than 100 kg ha−1 in the region. The agronomic optimum N rates for wheat and maize were 46–221 and 44–250 kg N ha−1 with means of 110 and 127 kg N ha−1, respectively. The environmentally safe N rates were 19–248 kg N ha−1 with mean of 107 kg N ha−1 for wheat, and 36–209 kg N ha−1 with mean of 99 kg N ha−1 for maize. It was found that agronomic optimum N rates from 61% of wheat and 52% of maize were higher than the environmentally safe N rates, implying that current N recommendation had the high potential risk of nitrate leaching. Hence, it is suggested that N recommendation should consider not only the agronomic optimum N but also environmentally safe N rate, especially in areas where are vulnerable to nitrate leaching the latter should be placed at the top priority.

Trivalent praseodymium (Pr3+) is the most established rare-earth ion for the direct generation of visible light. In our work, based on Pr-doped Lu3Al5O12 (LuAG) single crystal, cladding waveguides are fabricated by applying femtosecond laser inscription with different parameters. The main characteristics of the waveguides such as mode distributions, propagation losses are investigated. The investigations on confocal micro-photoluminescence enable us to illustrate femtosecond laser induced modifications in Pr:LuAG matrix. The waveguides are further pumped at a wavelength of 450 nm with an InGaN laser diode. Guided fluorescence emissions in visible range covering green, yellow-green, orange and red are obtained with a maximum slope efficiency of 4 × 10−4.

In this paper, practical stability is concerned for positive switched nonlinear time-varying (PSNTV) systems and positive switched linear time-varying (PSLTV) systems with disturbances. Based on a new definition on practical stability which can fully reflect the positivity of every component of the solution, sufficient conditions on practical stability of PSNTV systems are given by using the multiple max-separable Lyapunov function method. As an application of our criterion, sufficient criteria on practical stability are also provided for PSLTV systems with disturbances. Through our criterion, the systems' practical stability can be judged directly from the algebraic characteristics of the systems. At the end, examples are presented to illustrate the effectiveness of our results.

This paper focuses on perturbation analysis of the l1 conic optimization problem, which is defined as the optimization problem over the epigraph of the weighted l1 norm. The motivation for studying...

Short-term operation of a multi-objective reservoir system under inflow uncertainty has been receiving increasing attention, however, major challenges for the optimization of this system still remain due to the multiple and often conflicting objectives, highly nonlinear constraints and uncertain parameters in which derivative information may not be directly available. Population-based optimization methods do not rely on derivatives while generally have a slow convergence. This study presents a hybrid optimization model for short-term operation of multi-objective reservoirs under uncertainty that is derivative free and has a relatively fast convergence. The model incorporates a local improvement method called Mesh Adaptive Direct Search (MADS) into a population-based method NSGA-II and has no requirement for differentiability, convexity and continuity of the optimization problem. The operation of a multi-objective and multi-reservoir system on the Columbia River under inflow uncertainty is used as a case study. Overall, the hybrid model outperforms optimization models based on either the NSGA-II only or the MADS only. The model is intended for conditions where derivative information of the optimization problem is unavailable, which could have a wide array of applications in water resources systems.

Hydrologic regulation is an important ecosystem service, and is easily influenced by human disturbance. Many studies have been conducted on the impacts that human activities have on flow regime and regulating capacity by a single environmental factor. However, these studies have not clarified the comprehensive effects at sub-watershed scale; these effects are important for sub-watershed management. This research was conducted to reveal the spatial heterogeneity of hydrologic regulating service and identify the impact factors in China’s Yangtze River Basin. This basin is the largest in China and frequently floods. We built a new index based on the coefficients of variation for precipitation and runoff. The proposed indicator reflected the relative strength of regulating service effectively, and distinguished the basin into two different groups (A and B) of sub-watersheds. The hydrologic regulating index was significantly and positively correlated to slope and coverage of bush and forest, and negatively correlated to hydraulic projects, farmland, and urban area. Land-use changes have the greatest contribution (more than 60%) to differences in sub-watershed hydrologic regulating service. Compared with the sub-watersheds of group A, the sub-watersheds of group B suffered more severe human activity, for which the relative contributions to hydrologic regulating service were 32.18% (hydraulic projects), 18.21% (farmland) and 6.21% (urban area). These results indicated that the ecological effects of human activities should be a concern, and that restoration of the natural environment should play an important role for hydrologic regulating capacity enhancement. Group A sub-watersheds should explore the existing massive potential of (cascade) reservoirs for improving hydrologic regulating ability. Our results not only present a useful tool for watershed hydrologic regulating assessment, but lay a foundation for exploring differentiated management strategies of flood mitigation at sub-watershed scale.

We conducted a numerical analysis on high-K dielectric passivated AlGaN/GaN Schottky barrier diodes (HPG-SBDs) with a gated edge termination (GET). The reverse blocking characteristics were significantly enhanced without the stimulation of any parasitic effect by varying the dielectric thickness dge under the GET, thickness TP, and dielectric constant er of the high-K passivation layer. The leakage current was reduced by increasing er and decreasing dge. The breakdown voltage of the device was enhanced by increasing er and TP. The highest breakdown voltage of 970 V and the lowest leakage current of 0.5 nA/mm were achieved under the conditions of er = 80, TP = 800 nm, and dge = 10 nm. C-V simulation revealed that the HPG-SBDs induced no parasitic capacitance by comparing the integrated charges of the devices with different high-K dielectrics and different dge.

This paper optimizes the design and operation of integrated distributed energy systems of large buildings and light industrial plants. The integration reduces greenhouse gas (GHG) emissions and the annual total cost (ATC) beyond the best possible from individual energy systems and there is a sharp optimum with respect to the size of the confectionary plant, which maximizes the reduction of GHG emissions and minimizes ATC. In contrast to previous studies, the design accounts for plant heating demands at different temperature levels and sets plant production volumes as decision variables. Optimal design, operation, and production schedule have been determined via a mixed-integer nonlinear programming model. Integrated energy systems of two entities (confectionary plant and residential building) have been compared to the non-integrated entities equipped with combined cooling, heating, and power systems. The lowest ATC (−8%) of the integrated system and the maximum GHG reductions (−8.3%) occur at slightly different sizes of the plant. Such reductions require simultaneous optimization of integrated design and operation of energy systems and relative sizes of the confectionary plant and the residential building.

A high breakdown voltage GaN-on-Insulator based heterojunction field effect transistor with a partial back barrier (PB-GOI HFET) is proposed in this paper. The partial back barrier (PB) formed by AlGaN is located in the GaN channel layer, which can make the breakdown voltage improved significantly by modulating the distribution of electric field along the channel. PB-GOI HFET can not only maintain the original advantages of GOI structure, but also improve the breakdown voltage without degradation of frequency performance. Compared with a conventional GOI HFET, the proposed PB-GOI HFET with gate–drain distance of 5 μm possesses the breakdown voltage of 1200 V and the FOM of 3.12 GW/cm 2 , which increased by more than 353% and 976%. The novel PB-GOI HFET shows great prospects in power electronics applications.

In this paper, a novel high-K/low-K compound passivation AlGaN/GaN Schottky Barrier Diode (CPG-SBD) is proposed to improve the off-state characteristics of AlGaN/GaN schottky barrier diode with gated edge termination (GET-SBD) by adding low-K blocks in to the high-K passivation layer. The reverse leakage current of CPG-SBD can be reduced to 1.6 nA/mm by reducing the thickness of high-K dielectric under GET region to 5 nm, while the forward voltage and on-state resistance keep 1 V and 3.8 Ω mm, respectively. Breakdown voltage of CPG-SBDs can be improved by inducing discontinuity of the electric field at the high-K/low-K interface. The breakdown voltage of the optimized CPG-SBD with 4 blocks of low-K can reach 1084 V with anode to cathode distance of 5 μm yielding a high FOM of 5.9 GW/cm 2 . From the C-V simulation results, CPG-SBDs induce no parasitic capacitance by comparison of the GET-SBDs.

In this paper, we discuss the practical stability of positive systems. By using the comparison lemma, max-separable Lyapunov function and generalized integral inequality, we provide sufficient conditions on practical stability for nonlinear positive systems and linear time-varying positive systems with disturbances, respectively. Especially, the practical stability of linear time-varying positive systems is discussed under several different disturbance conditions. At the end, three examples are presented to illustrate the effectiveness of our approaches.

The combination of chemotherapy and photodynamic therapy has been proved to be a promising therapy for drug-resistant cancers. In this study, we report, for the first time, a novel two-fold interpenetration pillar-layered metal-organic frameworks (MOFs) material, using BODIPY-derivate bipyridine as linker and Photosensitizer (PS), named BBP-MOFs, was successfully synthesized to serve as a drug carrier and Photodynamic agent simultaneously. The BBP-MOFs could generate singlet oxygen (1O2) to perform PDT under 660 nm light irradiation, in the meantime, the anticancer drugs doxorubicin (DOX) could be loaded for chemotherapy. The results showed that BBP-MOFs exhibited a high drug loading content of 49.7% a controlled drug release and ideal biocompatibility. This DOX loaded BBP-MOFs was readily taken up by HeLa cells, and high levels of 1O2 were generated under light irradiation. This work provided strong evidence for BBP-MOFs as a promising new anticancer drug carrier and PDT candidate, the PDT and chemotherapy combined synergistic therapy revealed high therapeutic efficacy for cancer cells.

Accurate monitoring of motion and sleep states is critical for human health assessment, especially for a healthy life, early diagnosis of diseases, and medical care. In this work, a smart wearable sensor (SWS) based on a dual-channel triboelectric nanogenerator was presented for a real-time health monitoring system. The SWS can be worn on wrists, ankles, shoes, or other parts of the body and cloth, converting mechanical triggers into electrical output. By analyzing these signals, the SWS can precisely and constantly monitor and distinguish various motion states, including stepping, walking, running, and jumping. Based on the SWS, a fall-down alarm system and a sleep quality assessment system were constructed to provide personal healthcare monitoring and alert family members or doctors via communication devices. It is important for the healthy growth of the young and special patient groups, as well as for the health monitoring and medical care of the elderly and recovered patients. This work aimed to broaden the paths for remote biological movement status analysis and provide diversified perspectives for true-time and long-term health monitoring, simultaneously.

Binuclear iron phthalocyanine/reduced graphene oxide (bi-FePc/RGO) nanocomposite with good electrocatalytic activity for ORR in alkaline medium was prepared in one step. High angle annular dark field image scanning transmission electron microscopy (HAADF-STEM) and energy dispersive X-ray spectroscopy element mapping results show bi-FePc was uniformly distributed on RGO. An obvious cathodic peak located at about −0.23 V (vs. SCE) in CV and an onset potential of −0.004 V (vs. SCE) in LSV indicate the as-prepared bi-FePc/RGO nanocomposite possesses high activity which is closed to Pt/C for ORR. The ORR on bi-FePc/RGO nanocomposite follows four-electron transfer pathway in alkaline medium. Compared with Pt/C, there is only a slight decrease (about 0.02 V vs. SCE) for bi-FePc/RGO nanocomposite when the methanol exists. The excellent activity and methanol tolerance in alkaline solutions proves that bi-FePc/RGO nanocomposite could be considered as a promising cathode catalyst for alkaline fuel cells.

Early warning systems are widely used to safeguard water security, but their effectiveness has raised many questions. To understand why conventional detection methods fail to identify contamination events, this study evaluates the performance of three contamination detection methods using data from a real contamination accident and two artificial datasets constructed using a widely applied contamination data construction approach. Results show that the Pearson correlation Euclidean distance (PE) based detection method performs better for real contamination incidents, while the Euclidean distance method (MED) and linear prediction filter (LPF) method are more suitable for detecting sudden spike-like variation. This analysis revealed why the conventional MED and LPF methods failed to identify existence of contamination events. The analysis also revealed that the widely used contamination data construction approach is misleading.

Multifunctional chitosan-based nanoparticles were designed and synthesized by photosensitizer (PS) AZA-BODIPY grafting water-soluble chitosan as nanoshells and then loaded drug methotrexate (MTX) into the nanoshells, which generated chemotherapy, photothermal therapy (PTT), photodynamic therapy (PDT) and imaging into one system for synergistic therapy in vitro. The nanoshells in this designed nanostructure can serve as drug carriers to increase solubility, reduce toxicity and enhance the efficacy of synergistic PTT and PDT. Cell-viability indicated the low toxicity and safety of chitosan-based AZA-BODIPY nanoshells as carrier materials and the low-drug dosage of chitosan-based nanoparticles (half-maximal inhibitory concentration, IC50 = 34.5 μg/mL) is lower than that of pure drug MTX (IC50 = 56.9 μg/mL). Under light irradiation, photothermal temperature and MTT studies show that nanoparticles produce reactive oxygen species and exhibit photothermal conversion efficiency (38.3%). Thus, this study provides a multifunctional nanoparticle with chemotherapy, photothermal, photodynamic and imaging, synergistic therapy and diagnose for cancer treatment.

Phototheranostic agents are capable of both therapeutic and diagnostic potential, making them a promising strategy for cancer therapy. BODIPY is an outstanding photosensitizer for Photodynamic Therapy (PDT). Here we engineered a BODIPY-based phototheranostic nanoparticle with photo-chemo synergistic property and the nanoparticle MMC-Graphene@BODIPY-mPEG (MGBP) possesses excellent ROS production ability, high photothermal conversion efficiency (48%), and excellent therapy efficiency (HeLa cell viability was down to 17% after treatment) in vitro. Furthermore, because of its high fluorescence and anti-photobleaching ability of BODIPY and photothermal conversion ability of Graphene, MGBP showed superior fluorescence and photothermal imaging ability in the agar model. In summary, MGBP possessed the excellent potential for tumour tissue imaging-guided photo-chemo synergistic therapy.

In this work, we propose a flexible ferroelectric tunnel junction (FTJ) with a nanometer-thick single-crystalline BaTiO3 barrier prepared by exfoliating and transferring epitaxial BaTiO3 thin films onto flexible poly(styrenesulfonate)-doped poly(3,4-ethylenedioxythiophene) (PEDOT:PSS) conductive electrodes using a water-soluble Sr3Al2O6 sacrificial layer. The transferred freestanding BaTiO3 films remain single crystalline and exhibit clear ferroelectric hysteresis, no matter being flat or bent. A combined piezoelectric force microscopy and conductive atomic force microscopy measurement reveals that the Pt/BaTiO3/PEDOT:PSS FTJ shows a clear polarization direction modulated tunneling resistance. By using x-ray photoelectron spectroscopy, the polarization direction-dependent electrostatic potential profile of this flexible FTJ has been reconstructed, consistent with the observed resistance modulation.

We report on the fabrication of dual-line waveguides with low propagation losses and single-mode guidance in Pr:CaF2 crystals by applying femtosecond laser inscription. In contrast to the typical highly elliptic modes previously reported in dual-line waveguides, the guiding mode obtained in our work is highly-localized with a near-circular profile at wavelength of 633 nm. The investigations on confocal micro-photoluminescence and micro-Raman imaging enable us to illustrate the effect of different femtosecond laser filamentations on the localized refractive index change in Pr:CaF2 crystals. In company with the mode simulation by finite element method, we further reconstruct the refractive index distribution of the fabricated waveguides. Our results indicate that highly-localized refractive-index increment caused by compressive stress between the lower parts of the filaments is the main mechanism for waveguiding, whereas the damage-induced refractive-index reductions at filaments and in the region between the upper parts of the filaments are responsible for the strong light confinement in both horizontal and vertical directions.

Soybean oil with fried repeatedly at high temperature produces harmfully substances to threaten human health. In this paper, Adaboost-SVM (RBF) classification model combined with near infrared spectroscopy (NIRS) was proposed to detect frying times of soybean oil based on the optimal selection of crucial parameters and the combination of Adaboost, support vector machine (SVM) of radial basis function (RBF) as the kernel function. Herein, four modes were designed to divide 15 fryings into primary and secondary stages, then the created classification models were compared. Specially, after classifying as I, II, III class by mode 3, the accuracy of primary model established by Adaboost reached 98 %. Afterwards, spectra with pre-processed by various methods were analyzed. As expected that the performance of secondary models were significantly reinforced, especially the accuracy of SVM (RBF) model increased from 76 % to 88.89 %. Additionally, successive projections algorithm (SPA) was applied to obtain relevant wavelengths. When the dimensions of I, II, III class were severally reduced to 14, 6, 8, the accuracy of SVM (RBF) model was the best average value of 93.33 %. Finally, the results of external validation indicated that the accuracy of primary and secondary models reached 95.55 %, 91.11 %, respectively.

In this study, a general framework integrating a data-driven estimation model is employed for contamination event detection in water sources. Sequential canonical correlation coefficients are updated in the model using multivariate water quality time series. The proposed method utilizes canonical correlation analysis for studying the interplay between two sets of water quality parameters. The model is assessed by precision, recall and F-measure. The proposed method is tested using data from a laboratory contaminant injection experiment. The proposed method could detect a contamination event 1 minute after the introduction of 1.600 mg l(-1) acrylamide solution. With optimized parameter values, the proposed method can correctly detect 97.50% of all contamination events with no false alarms. The robustness of the proposed method can be explained using the Bauer-Fike theorem.

Satellite networks support a wide range of service and provide global coverage. Moreover, LEO satellites, which have global coverage potential, have caused great attention in the field of satellite communication. Due to satellites’ mobility, an efficient and stable routing algorithm is necessary for transmission in satellite networks. In this paper, a Distributed Multi-Path Routing algorithm (DMPR) using Earth-fixed satellite systems is proposed. DMPR adopts the Polar orbit constellation in which each satellite has four ISLs (inter satellite link) with the neighbor satellites. A traffic-light is set for every ISL to judge the blocking while avoiding some busy path and reducing the delay.

The relative contributions of different factors to the variation in surface runoff have been broadly quantified. However, little attention has been paid to how these relative contributions have changed over time. We analyzed the changes in surface runoff during 1980–2010 in six subbasins in the mountainous region of the Haihe River Basin, one of the most serious water shortage regions in China, and identified the changes in the relative contributions of climate (precipitation and temperature) and land-use to surface runoff decrease. There was a decreasing tendency in surface runoff in all subbasins, four of which had an abrupt change point around 1998. Comparing the relative contributions before and after 1998 in the four subbasins, the average influence of climate was found to decline dramatically from 67.1% to 30.5%, while that of land-use increased from 23.9% to 69.5% mainly due to the increase of forest area. Our results revealed that the primary environmental factor responsible for runoff variations was not constant, and an alternation may accentuate the impact and stimulate an abrupt change of runoff in semiarid and semihumid mountainous regions. This will help in taking tracking measures to deal with the complex water resource challenges according to different driving factors.

Energy efficiency is an important factor to optimize the multi-hop forwarding strategy. PD (Pairing-inspired Dijkstra) multi-hop data forwarding algorithm is proposed to share cellular spectrum resources with D2D (device-to-device) users. Candidate multiplexing channel model is established in our proposal. Based on this model, PD algorithm solves the issue on channel and path selection. PD algorithm includes two parts, KM dichotomous matching algorithm and multiple iterations for Dijkstra algorithm. Under energy efficiency and QoS (Quality of Service) constraint, PD algorithm selects optimal transmission path among D2D users. Furthermore, the energy efficiency and transmission delay are evaluated in simulation section under PD, Dijkstra and CD (Closest to Destination) algorithm. Simulation results indicate that PD has better performance on energy efficiency and E2E (End to End) delay.

Determining acid detergent fiber (ADF) content in corn straw with Visible/Near-Infrared (Vis/NIR) spectroscopy, associated suitable chemometrics methods, is both feasible and relevant for the corn breeding. The work demonstrated that Vis/NIR combined with support vector regression (SVR) realized the nondestructive determination of ADF content. Herein, after optimized spectra and model parameters by pretreatment methods and genetic algorithm (GA), the preeminent SVR model was confirmed. For selecting feature bands, the modified synergy interval (si) algorithm was applied to unevenly divide full-spectra into seven subintervals, the performance of 128 siSVR models with different combinations was investigated. It turned out that the determination coefficient (R2), root mean square error of prediction (RMSEP), residual predictive deviation (RPD), relative standard deviation (RSD) of test set of SVR model successively reached 0.9897, 0.4037, 9.8689, 0.0094. Meanwhile, the performance of siSVR model was proven to further improve when the penalty parameter C and kernel function parameter g respectively were 99.9904, 0.0051, the group of [2,3,5,6] was determined. Besides, the second subinterval were subdivided into I, II, III sub-bands to further dimension reduction. As expected that siSVR model reached for best level when the suited group was [2(I, III), 3, 5, 6], R2, RMSEP, RPD, RSD were 0.9943, 0.2885, 13.2688, 0.0066, respectively. Finally, compared with other models, the results of external validation indicated that the proposed method presented the excellent performance, which could meet the requirements of ADF analysis.

Ecosystem services (ES) underpin human well-being, but their complex synergies or trade-offs are a challenge for matching ES supply and demand. This study presents a framework for integrating ES synergies/trade-offs and approaches (“win-win”, “small loss-big gain” and “ES replacement”) to improve the match between ES supply and demand. We applied the framework in a watershed on China’s Hainan Island, where local ES supply and demand are severely out of balance. Based on the analyses of ES synergies/trade-offs and their drivers, selecting the “win-win” approach (planting rubber with intercropped medicinal plants) and “ES replacement” approach (transitioning some secondary forest into rubber intercropped with medicinal plants) together could effectively improve the match between the supply and demand of agricultural product provision (its supply-demand ratio increased from 0.65 to 1.3) without disrupting the established supply-demand matches of water resource provision, soil retention, flood mitigation and water purification services. Our framework contributes to a new perspective for improving the match between ES supply and demand.

Recently, increasingly sophisticated studies have investigated the relationship between agrarian livelihoods and the environment, as well as rural–urban interactions in developing countries. The policies developed to respond to these dynamics can constrain livelihood options or provide additional opportunities. In the present study, using a modified version of the telecoupled sustainable livelihood framework to generalize dynamic livelihood strategies in the context of rural–urban transformation and by focusing on recent research in China, we review important factors that shape rural livelihood strategies as well as the types of strategies that typically intersect with livelihood and environmental dynamics. We then examine telecoupled rural–urban linkages given that the dynamics of the livelihood strategies of farmers can cause flows of labor, capital, ecosystem services, and other processes between rural and urban areas, thereby placing livelihood strategies in a dynamic context, which has not been considered widely in previous research. We show that most previous studies focused on the reduction of environmental impacts via livelihood diversification and rural–urban migration. We propose several areas for future policy development and research.

Opportunistic Network as a novel networking, taking advantage of meeting opportunities of mobile nodes, completes the message transmission from the source node to the destination node through the way of each hop. Mobility model decides how the nodes move and is used to analyze network performance with various protocols, such as routing protocols, data dissemination protocols, etc. Currently many mobility models are proposed by researchers. To evaluate these mobility models, an analysis method is proposed. So we propose a method by analyzing mobile distance to assess node mobility models. This paper firstly introduced the commonly used mobility models based on ONE simulation platform, and then a calculation method of node mobile distance is put forward. Next, it was simulated and discussed that we have considered the nodes mobility features by mobile distance. Finally, we use the node contact duration and node inter-contact time as a validation, to make an evaluation for node mobility model.