Characteristics Of Dynamic Change Research Articles

Predicting Abrupt Depletion of Dissolved Oxygen in Chaohu Lake using CNN-BiLSTM with Improved Attention Mechanism

Depletion of dissolved oxygen (DO) is a significant incentive for biological catastrophic events in freshwater lakes. Although predicting the DO concentrations in lakes with high-frequency real-time data to prevent hypoxic events is effective, few related experimental studies were made. In this study, a short-term predicting model was developed for DO concentrations in three problematic areas in China's Chaohu Lake. To predict the DO concentrations at these representative sites, which coincide with biological abnormal death areas, water quality indicators at the three sampling sites and hydrometeorological features were adopted as input variables. The monitoring data were collected every 4 hours between 2020 and 2023 and applied separately to train and test the model at a ratio of 8:2. A new AC-BiLSTM coupling model of the convolution neural network (CNN) and the bidirectional long short-term memory (BiLSTM) with the attention mechanism (AM) was proposed to tackle characteristics of discontinuous dynamic change of DO concentrations in long time series. Compared with the BiLSTM and CNN-BiLSTM models, the AC-BiLSTM showed better performance in the evaluation criteria of MSE, MAE, and R2 and a stronger ability to capture global dependency relationships. Although the prediction accuracy of hypoxic events was slightly worse, the general time series characteristics of abrupt DO depletion were captured. Water temperature regularly affects DO concentrations due to its periodic variations. The high correlation and the universal importance of total nitrogen (TN) and total phosphorus (TP) with DO reveals that point source pollution are critical cause of DO depletion in the freshwater lake. The importance of NTU at the Zhong Miao Station indicates the self-purification capacity of the lake is affected by the flow rate changes brought by the tributaries. Calculating linear correlations of variables in conjunction with a permutation variable importance analysis enhanced the interpretability of the proposed model results. This study demonstrates that the AC-BiLSTM model can complete the task of short-term prediction of DO concentration of lakes and reveal its response features of timing and magnitude of abrupt DO depletion.

Uncertain process-based integration of ADT and field data of PCB in airborne equipment and PCB residual lifetime evaluation

Accurately evaluating the lifespan of the Printed Circuit Board (PCB) in airborne equipment is an essential issue for aircraft design and operation in the marine atmospheric environment. This paper presents a novel evaluation method by fusing Accelerated Degradation Testing (ADT) data, degradation data, and life data of small samples based on the uncertainty degradation process. An uncertain life model of PCB in airborne equipment is constructed by employing the uncertain distribution that considers the accelerated factor of multiple environmental conditions such as temperature, humidity, and salinity. In addition, a degradation process model of PCB in airborne equipment is constructed by employing the uncertain process of fusing ADT data and field data, in which the performance characteristics of dynamic cumulative change are included. Based on minimizing the pth sample moments, an integrated method for parameter estimation of the PCB in airborne equipment is proposed by fusing the multi-source data of life, degradation, and ADT. An engineering case illustrates the effectiveness and advantage of the proposed method.

Assessment of ecological security risk in rocky desertification area based on land-use change model

Social and economic development, production and living needs, other human behavior requirements and various ecological engineering construction are considered as the main influencing factors of land spatial pattern changes and land ecological security risks in rocky desertification areas. From the perspective of land-use spatial change, the impact of human activities and resource utilization on land ecological security risks can be more intuitively analyzed. Based on the land-use change survey data of Phase 4 of Honghe Prefecture, China, the study measures the characteristics of land-use transfer flow and land-use dynamic change, analyzes the main influencing factors and comprehensively constructs the land ecological security risk index model, on which the land ecological security risk is classified. The results showed that the land ecological security risk degree in the three stages of the study area from 2014 to 2020 was 2016–2018 > 2018–2020 > 2014–2016, and had obvious regional characteristics. Among many influencing factors, the different activities/projects (positive or negative) types, time and intensity affect the land-use transfer flow and dynamic change characteristics, resulting in corresponding changes in the risk of land-use ecological security. Among them, man-made destruction and construction activities have the most significant negative effects on land ecological status. The empirical analysis proved that building an ecological security risk index based on the direction, area, and rate of spatial changes in land-use can accurately reflect the degree of desertification risk in rocky desertification areas. The study results can provide important information on the impact of regional development and the environmental governance policies of the land-use change in rocky desertification areas.

Seasonal thermal comfort and adaptive behaviours for the occupants of residential buildings: Shaoxing as a case study

This study aimed to investigate the thermal comfort requirements in residential buildings and establish an adaptive thermal comfort model. A two-year field study was conducted on residential buildings in Shaoxing, Zhejiang Province, China. A total of 172 apartments (187 people) were surveyed, and 2400 valid questionnaires on thermal sensation from residents were obtained in two years. The results showed that the thermal comfort requirements of residents change with the seasons: Different seasons lead to changes in the range of thermal comfort zones and the residents’ thermal adaptation models, which are related to the climatic characteristics of each season. Compared with the traditional year-round adaptive thermal comfort model, seasonal models could reflect the status of the residents’ thermal adaptation caused by the characteristics of dynamic climate change more comprehensively and accurately. In addition, this study determined the residents’ psychological and behavioural adaptability to the seasons and found the characteristics of thermal sensation and requirements for thermal comfort in different seasons. In conclusion, this study provides people in the study area with basic knowledge of their thermal comfort requirements. The results could be used as a basis to improve energy efficiency and meet comfort needs in the future.

Research on a Novel Denoising Method for Negative Pressure Wave Signal Based on VMD

The key to accurately locate pipeline leakage is to effectively reduce the noise in the leakage signal. However, the leakage signal has the characteristics of nonlinear and dynamic change, and the denoising effect of the traditional method is limited. In order to reduce the positioning error caused by noise, a novel denoising method based on variational mode decomposition (VMD) is proposed. First, the correlation coefficient is used to screen effective intrinsic mode function components. Then, an optimization method of VMD decomposition layers <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> by using minimum information entropy is utilized. Thus, the optimal number of layers and noise reduction signal can be obtained. Finally, the leakage point can be obtained by the principle of negative pressure wave (NPW). Simulation results show that the SNR can effectively improved by using the method in this paper. In laboratory experiments, this method can be used to effectively denoise the pressure signal while preserving the original signal characteristics as much as possible. Furthermore, From the perspective of positioning accuracy, compared other methods, the proposed method method can achieve better positioning effect, and the average relative positioning error is 2.03%.

Study on the diversity of mental states and neuroplasticity of the brain during human-machine interaction.

With the increasing demand for human-machine collaboration systems, more and more attention has been paid to the influence of human factors on the performance and security of the entire system. Especially in high-risk, high-precision, and difficult special tasks (such as space station maintenance tasks, anti-terrorist EOD tasks, surgical robot teleoperation tasks, etc.), there are higher requirements for the operator's perception and cognitive level. However, as the human brain is a complex and open giant system, the perception ability and cognitive level of the human are dynamically variable, so that it will seriously affect the performance and security of the whole system. The method proposed in this paper innovatively explained this phenomenon from two dimensions of brain space and time and attributed the dynamic changes of perception, cognitive level, and operational skills to the mental state diversity and the brain neuroplasticity. In terms of the mental state diversity, the mental states evoked paradigm and the functional brain network analysis method during work were proposed. In terms of neuroplasticity, the cognitive training intervention paradigm and the functional brain network analysis method were proposed. Twenty-six subjects participated in the mental state evoked experiment and the cognitive training intervention experiment. The results showed that (1) the mental state of the subjects during work had the characteristics of dynamic change, and due to the influence of stimulus conditions and task patterns, the mental state showed diversity. There were significant differences between functional brain networks in different mental states, the information processing efficiency and the mechanism of brain area response had changed significantly. (2) The small-world attributes of the functional brain network of the subjects before and after the cognitive training experiment were significantly different. The brain had adjusted the distribution of information flow and resources, reducing costs and increasing efficiency as a whole. It was demonstrated that the global topology of the cortical connectivity network was reconfigured and neuroplasticity was altered through cognitive training intervention. In summary, this paper revealed that mental state and neuroplasticity could change the information processing efficiency and the response mechanism of brain area, thus causing the change of perception, cognitive level and operational skills, which provided a theoretical basis for studying the relationship between neural information processing and behavior.

Secure routing protocol based on dynamic reputation and load balancing in wireless mesh networks

Aiming at the characteristics of dynamic topology change and vulnerability of wireless mesh networks (WMN), a secure routing protocol based on dynamic reputation and load balance (SRP-DRLB) is proposed to improve the routing security and load balance. By dynamically predicting of the reputation and traffic of the node in WMN, SRP-DRLB adopts edge weight strategy and node load idleness to avoid the competitive access of a large number of data packets to nodes with high reputation. SRP-DRLB dynamically adjusts routes according to the real-time status of network nodes’ reputation and traffic, reducing the impact of malicious nodes on the network and the overload of high-reputation nodes, thus improving the identification rate of malicious nodes and node load balancing. Simulation results show that SRP-DRLB can effectively ensure the security of data transmission, and it has the advantages of improving the identification rate of malicious nodes, the success rate of packet transmission and avoiding network congestion.

Study on the Measures for Optimizing China’s Provincial Territorial Space Based on the Perspective of Resource and Environmental Carrying Capacity in the New Situation

The comprehensive resource and environment carrying capacity (RECC) evaluation is an important method for measuring the rationality of the population, resource, and environment allocation, which is an important scientific guidance for scientific research and the judgment of regional economic and social development potential and the optimization of the national land spatial pattern. This paper constructs a comprehensive evaluation index system of the RECC under the new situation of climate policy and high-quality economic development; it analyzes the factors influencing the RECC, the overall level, the spatial difference, and the carrying status by using the TOPSIS model based on the entropy weight method, and it identifies the shortcomings; then, it analyzes the characteristics of regional dynamic change and sustainable development trend, and finally, it simulates the optimal spatial pattern under the scenario simulated by the FLUS model. The conclusions are as follows: ① the resource factors have the greatest influence on the carrying capacity of the resources and the environment, followed by economic factors. Among them, per capita water resources, forest coverage rate, and health institutions have the highest impact on RECC. ② The overall level of comprehensive RECC from 2015 to 2020 shows an upward trend, and although the positive impact of resource-led provinces on the level of economic development power and RECC is greater than the negative one, the environmental support is the shortcoming of the future development of the regional economy. ③ The overall spatial performance of RECC is characterized as being high in Guanzhong, second in northern Shaanxi, and low in southern Shaanxi. The northern area of Yulin in the Guanzhong Plain City Cluster, which is an important national energy chemical base, is the core of the national-level urbanization development areas, and the northern area of the Guanzhong Plain City Cluster is the key choice of the provincial-level urbanization development areas. The area along the west bank of the Yellow River in the Qinba Mountain area in southern Shaanxi and the Baiyu Mountain area in northern Shaanxi can be positioned as national key ecological function areas.

Research on Monitoring Data Security Sharing Method for Hydropower Station Operation and Maintenance

The computer monitoring system centrally and uniformly manages the hydropower stations in the basin, which has high operation efficiency. The current data security sharing methods can not solve the multi-party trust problems such as data ownership and data security. In this regard, a monitoring data security sharing method for hydropower station operation and maintenance is proposed. The monitoring data of hydropower station comes from multiple independent operation systems developed by different suppliers according to different application requirements. The multi-source data are integrated and processed to meet the interactive needs of users. User permission has the characteristics of dynamic change, which can identify the permission attributes. Create a trusted container based on the user ID, locate the monitoring data, and trace the source in data sharing and storage. The access policy is formulated by the data user and bound with the private key, while the data is given an attribute set during encryption. Each data user has a corresponding access policy and a private key corresponding to the access policy, so as to realize the security sharing of monitoring data. The test results show that the design method in this paper can effectively reduce the communication overhead and storage overhead, and has good computing performance.

Dynamic stress analysis of a metro bogie due to wheel out-of-roundness based on multibody dynamics algorithm

In metro vehicle systems, the dynamic stress and vibration of the bogie frame have a significant impact on the safety and reliability of vehicles. This study presents a fracture failure analysis of the bogie frame for the metro vehicle. The analysis consists of a bogie frame dynamic stress test, a wheel out-of-roundness (OOR) measurement and a vibration transmissibility test of the vehicle which is also used for operational modal analysis of the bogie frame. The field test result shows that the bending of cross beam combined with torsion of side beams(49.5 Hz) which are aroused by the wheel OOR mainly contribute to the fatigue failure of the bogie frame. To investigate the effect of wheel OOR on the fatigue failure of the bogie frame, the multibody system (MBS) model of the metro vehicle was developed. The MBS model accounts for the flexibility of the bogie frame and the nonlinearity of wheel-rail contact. Furthermore, the modal stress recovery method was adopted to study the dynamic responses of the bogie frame. The measured wheel OOR data is used to validate the efficiency of the model and investigate the characteristics of dynamic stress in time histories as well as frequency spectra. Moreover, the dynamic stress of fracture site in the bogie frame with consideration of ideal polygonal wear in radial deviation including different orders and variable amplitudes was investigated. The phase shift of wheel OOR between different wheels proves to be influential in the bogie frame vibration and thus the characteristics of dynamic stress change accordingly. The recommended limit values of wheel OOR amplitude are shown based on numerical results.

Retraction Note: Cross basin water diversion project based on VR visual system and urban public art design

The main research content of this paper is VR visualization allocation algorithm which can realize memory optimization. The use of this algorithm can effectively reduce the redundancy of modeling and centralized processing of multiple models, reduce the time consumption, improve the efficiency of modeling, and ensure the smooth operation of VR visualization system. It is important to note that the economic development of the region will affect the visualization effect, especially when studying the water shortage in high-level areas, so in the actual water resource problem-solving process, the cross basin water transfer method is often adopted. The inter basin water transfer project needs to span the distance of time and space in the process of implementation. It has the characteristics of multi-objective, multi task, dynamic change, and unknown. These characteristics determine that the inter basin water transfer project is a complex and arduous task. Water diversion project is born to solve the uneven distribution of regional water resources, which can effectively solve the problem of water supply and consumption. In addition, the water diversion project can also improve the ecological conditions of the region and can also improve the quality of drinking water in the receiving area, so as to improve the quality of life of the people in the region. With the continuous progress of society, urban construction began to pay more attention to public art. This paper studies the current situation of public art in modern cities in China and puts forward plans and suggestions in line with China’s national conditions according to the actual situation and prospects the future development of urban art in China. Urban public art originated in Western countries and developed rapidly after entering China. It is perfectly integrated with Chinese culture, forming a unique development path for China.

Change trend analysis of the time-series shadow-eliminated vegetation index (SEVI) for the Wuyishan Nature Reserve with the Sen+Mann-Kendall method

In order to reveal the characteristics of spatial distribution and dynamic change of the forest in the Wuyishan Nature Reserve from 2000 to 2019, the recently proposed shadow-eliminated vegetation index (SEVI) and the method of Sen+Mann-Kendall were used together in this study. The results show a trend of “decreasing first and then increasing” of vegetation cover change of the Reserve during the sub-periods of 2000-2011 and 2012-2019, but, as a whole, the vegetation cover of the Reserve was improved during 2000-2019, with 43.76% slight improvement and 55.18% significant improvement, approximately.

Evaluation of Slope Safety Using the Pignistic Probability-based Analysis Method

Dong, C.H.; Zhang, M.; Yang, H.M., and Xu, X.B., 2020. Evaluation of slope safety using the pignistic probability-based analysis method. In: Guido Aldana, P.A. and Kantamaneni, K. (eds.), Advances in Water Resources, Coastal Management, and Marine Science Technology. Journal of Coastal Research, Special Issue No. 104, pp. 302–307. Coconut Creek (Florida), ISSN 0749-0208.On the basis of the slope stability analysis using the pignistic probability-based analysis method, considering the characteristics of dynamic change of parameters under the actual working conditions, an indoor model was built. The pignistic probability-based analysis method was suitable for the uncertainty working conditions caused by the fact that soil material parameters changed with water level and other conditions in the reservoir bank slope stability analysis, and the analysis results were consistent with the monitoring results. This study can provide a reference for other laboratory model tests of slope and a new solution for large slope stability analysis.

A Study on the Spontaneous Combustion Oxidation Properties of Unloaded Coal at Various Surrounding Rock Temperatures

ABSTRACT Based on effects of the deep surrounding rock temperature (Tsr) on the oxidation properties of mined coal, a thermodynamic experimental system for loaded coal oxidation is employed to examine the oxidation properties of readily oxidizable raw coal samples at various Tsrs and comparatively analyze the patterns of change in the oxygen (O2) consumption rate and the carbon monoxide (CO) concentration (CCO) with Tsr. The infrared (IR) spectra of unloaded coal samples oxidized at various Tsrs were separately fitted to Gaussian curves and Lorentzian curves by using the IR analysis software OMNIC. The following experimental results indicate that Tsr significantly affects the oxidation properties of the coal. The initial Tsr is higher and the rate of increase in the coal temperature is faster during the early stage of oxidation, and the coal–O2 complex effect is higher and the rate of consumption of O2 by coal is higher. The CCO produced by each coal sample continuously increased as Tsr increased. The amount of CO that was produced slowly and linearly increased as Tsr increased during the early stage of oxidation, and it approximately exponentially increases as Tsr increased during the later stage of oxidation. Additionally, the amount of CCO produced is increased with the increase in initial Tsr during the coal oxidation process. By using Fourier-transform IR (FTIR) spectroscopy, microstructural analysis of oxidized coal samples reveals that the characteristics of dynamic change in the micro-active groups (e.g. hydroxyl groups, O-containing functional groups and aromatic and aliphatic hydrocarbons) of unloaded coal samples at various Tsrs, and it also reasonably determines the micro-mechanism of the oxidation properties of unloaded coal samples at various Tsrs.

Experimental study on stress wave attenuation and energy dissipation of sandstone under full deformation condition

Excavation behaviours not only destroy the balance of original stress in rock mass but lead to the redistribution of initial stress, resulting in rock mass in a new stress environment. The static stress in rock mass has the characteristics of dynamic change. For the purpose of investigating the effect of increasing static stress on attenuation mechanism and energy dissipation of stress wave in sandstone under the overall deformation condition, small disturbance experiments on sandstone bar are carried out with a modified split-Hopkinson pressure bar test system. The stress waveform, p wave velocity, temporal and spatial attenuation of amplitude, and energy dissipation are studied under various static stresses. Results show that stress waveforms at different locations are approximately the same, those at the same locations vary greatly, and the tensile waves that appeared at the tails of stress waves are larger with increasing static stress. With increasing static stress, p wave velocity experiences a dramatic increase, then develops gently, and finally a sharp decrease; the stress demarcation points are σs/σc = 30% and σs/σc = 55%, respectively. P wave velocity can be predicted by a quadratic equation when σs/σc > 63.69%. The relation between longitudinal wave velocity and static stress can be described by a quadratic function. Stress wave amplitudes decrease exponentially with increasing distance and time. Values of temporal spatial response intensity (RI) and spatial RI are approximately equal and present the same development tendency of nonlinear and linear stages due to the same dimensions. Values of temporal attenuation characteristic (AC) and spatial AC are differed by 2 or 3 orders of magnitude although they present the same development tendencies. Ratios of RI and AC can indicate the sensitivity of temporal and spatial attenuation to different static stresses. Full-wave energy declines in an exponential function with increasing static stress and decays as a logarithmic function with increasing distance. Widespread attenuation characteristics like these should provide a theoretical basis for rock mass stability analysis.

Dynamic Changes Analysis and Hotspots Detection of Land Use in the Central Core Functional Area of Jing-Jin-Ji from 2000 to 2015 Based on Remote Sensing Data

The article uses GIS spatial analysis and grid technologies to study the dynamic changes, hotspot regions, and driving forces in land use of the central core functional area of Jing-Jin-Ji. The research results are as follows: from 2000 to 2015, the main types of land use in the central core functional area of Jing-Jin-Ji are cultivated land, woodland, and built-up land. In the period of 2005–2010, the transfer between built-up land and cultivated land was frequent. The dynamic degree of single land use in unused land was highest. It also finds out that the dynamic degree of the integrated land use from 2005 to 2010 was higher. The center of gravity transfer of the dynamic degree of integrated land use was concentrated in research area. As for the hotspots, their number and scope are increasing, and the positions located in the edge of original main urban area and developed transportation network. The main characteristics of land use dynamic change in the study area are the rapid decrease of cultivated land area and rapid growth of built-up land. The spatial agglomeration of economic factors caused by human activities has an important influence on the spatial and temporal dynamic changes of land use.

An event-related potential study of visual spatial attention span in children with Chinese learning disability

Objective To explore whether there is a visual spatial attention span deficit in children with Chinese language learning disability and the characteristics of brain electrophysiological dynamic change. Methods Adopting event-related potentials(ERP) technology and levels of visual spatial attention span with fixed location cuing pa-radigm were used to explore the characteristics of brain electrophysiological dynamic change. Results Based on the behavioral data, the repeated findings of analysis of variance on reaction time showed that both the main effect of the type of subjects[F(1, 35)=4.34, P<0.05, η2=0.11], and the main effect of attention span[F(1, 35)=138.75, P<0.001, η2=0.79] had statistical significance.The repeated analysis of variance on accuracy showed that the main effect of subjects type[F(1, 35)=4.99, P<0.05, η2=0.13], and the main effect of attention span[F(1, 35)=101.83, P<0.01, η2=0.74] were significantly different.Under large and small attention span conditions, the children with Chinese language learning disability showed a longer time of reaction and a lower accuracy rate than the children in the control group.With the electroencephalograph(EEG) data and under large and small attention span conditions, the Chinese learning disability children showed enhanced P1 amplitude and reduced N1 amplitude. Conclusions There is a visual spatial attention span deficit in children with Chinese learning disability which may be caused by a weak primary sensory processing ability and divided attention deficit. Key words: Chinese learning disability; Attention span; Event-related potential; Child

The groningen laryngomalacia classification system--based on systematic review and dynamic airway changes.

Laryngomalacia is the most common cause of dyspnea and stridor in newborn infants. Laryngomalacia is a dynamic change of the upper airway based on abnormally pliable supraglottic structures, which causes upper airway obstruction. In the past, different classification systems have been introduced. Until now no classification system is widely accepted and applied. Our goal is to provide a simple and complete classification system based on systematic literature search and our experiences. Retrospective cohort study with literature review. All patients with laryngomalacia under the age of 5 at time of diagnosis were included. Photo and video documentation was used to confirm diagnosis and characteristics of dynamic airway change. Outcome was compared with available classification systems in literature. Eighty-five patients were included. In contrast to other classification systems, only three typical different dynamic changes have been identified in our series. Two existing classification systems covered 100% of our findings, but there was an unnecessary overlap between different types in most of the systems. Based on our finding, we propose a new a classification system for laryngomalacia, which is purely based on dynamic airway changes. The groningen laryngomalacia classification is a new, simplified classification system with three types, based on purely dynamic laryngeal changes, tested in a tertiary referral center: Type 1: inward collapse of arytenoids cartilages, Type 2: medial displacement of aryepiglottic folds, and Type 3: posterocaudal displacement of epiglottis against the posterior pharyngeal wall.

Exploring bacterial community structure and function associated with atrazine biodegradation in repeatedly treated soils

Substantial application of the herbicide atrazine in agriculture leads to persistent contamination, which may damage the succeeding crops and pose potential threats to soil ecology and environmental health. Here, the degradation characteristics of atrazine and dynamic change of soil bacterial community structure and function as well as their relations were studied during three repeated treatments at the recommended, double, and five-fold doses. The results showed that the degradation half-life of atrazine obviously decreased with increased treatment frequency. Soil microbial functional diversity displayed a variation trend of suppression–recovery–stimulation, which was associated with increased degradation rate of atrazine. 16S amplicon sequencing was conducted to explore bacterial community structure and correlate the genus to potential atrazine degradation. A total of seven potentially atrazine-degrading bacterial genera were found including Nocardioides, Arthrobacter, Bradyrhizobium, Burkholderia, Methylobacterium, Mycobacterium, and Clostridium. These bacterial genera showed almost complete atrazine degradation pathways including dechlorination, dealkylation, hydroxylation, and ring cleavage. Furthermore, the relative abundance of four of them (i.e., Nocardioides, Arthrobacter, Methylobacterium, and Bradyrhizobium) increased with treatment frequency and atrazine concentration, suggesting that they may participate in atrazine degradation during repeated treatments. Our findings reveal the potential relationship between atrazine degradation and soil bacterial community structure in repeatedly treated soils.

Identity-based cluster key agreement scheme in Ad Hoc network

In view of the characteristics of limited energy and dynamic change in Ad Hoc network,an identity-based group key agreement scheme was presented.The topology was in a structure composed by clusters,and allowed the synchronous execution of multi-party key agreement protocols based on pairings.The number of cluster members did not affect the key agreement,and it did not require interactivity during the key agreement.It provided the authentication and dynamics.In addition,the scheme was proved semantics secure under the Decisional Bilinear Diffie-Hellman(DBDH) problem.At last,compared with the previous schemes,the proposed scheme has advantages in terms of negotiation rounds and authentication.