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Highway traffic systems are complex and variable, and studying the bifurcation characteristics of traffic flow systems and designing control schemes for unstable bifurcation points can alleviate traffic congestion from a new perspective. Bifurcation analysis is used to explain the changes in system stability, identify the unstable bifurcation points of the system, and design feedback controllers to realize the control of the unstable bifurcation points of the traffic system. It helps to control the sudden changes in the stable behavior of the traffic system and helps to alleviate traffic congestion, which is of great practical significance.

In this paper, we improve the macroscopic traffic flow model by integrating severe weather factors such as rainfall, snowfall, and dust. We use traveling wave transform to convert it into a traffic flow stability model suitable for branching analysis, thus converting the traffic flow problem into a system stability analysis problem. First, this paper derives the existence conditions of the model Hopf bifurcation and saddle-node bifurcation for the improved macroscopic model, and finds the stability mutation point of the system. Secondly, the connection between the stability mutation points and bifurcation points of the traffic system is analyzed. Finally, for the unstable bifurcation point, a nonlinear system feedback controller is designed using Chebyshev polynomial approximation and stochastic feedback control method.

The Hopf bifurcation is delayed and completely eliminated without changing the equilibrium point of the system, thus controlling the abrupt behavior of the traffic system.

Currently there are fewer studies to explain the changes in the stability of the transportation system through bifurcation analysis, in this paper; we design a feedback controller for the unstable bifurcation point of the system to realize the control of the transportation system. It is a new research method that helps to control the sudden change of the stable behavior of the traffic system and helps to alleviate traffic congestion, which is of great practical significance.

The creation of partnerships among companies, governments and universities can improve innovation and the technological development of institutions. As innovation is a multidimensional concept, more nuanced research is needed to identify, which dimensions of innovation firms should focus on them. This paper aims to investigate the influence of attitude to knowledge sharing (KS) factors, learning organization and creativity on the innovation in marketing biotechnology firms. So, the purpose of this paper is to examine the influence of learning organization, attitude to KS, creativity, information technology (IT) acceptance, KS culture and trust on the innovation by presenting a new framework and a model.

The structural equation modeling technique is used to examine the reliability and validity of the measurement of the provided model. Data were collected by questionnaires. A case study was carried out in 100 marketing biotechnology firms in the Tehran of Iran. In this paper, smart partial least squares 2.0 was used to evaluate the measurement.

The result showed that all hypotheses of this research are proved. Also, the results have shown that the attitude to KS, learning organization and creativity affect the innovation in marketing biotechnology firms. As an overall result, the managers should create an enhanced knowledge bank to increase and encourage the KS among employees, thus creating and enhancing innovation in organizations. Also, the results have shown that marketing shortages were mostly connected to access to human resources with related management and marketing experiences and were mainly felt by firms introducing discontinuous novelties.

The main limitation of this paper is that the sample was retrieved from 384 employees in 100 marketing biotechnology institutions. The larger number of samples can yield better results. Next, even though the respondents’ profiles indicated a high probability of them being cognizant of their organization’s efforts in inter-firm KS, learning, creativity and innovation with three or four respondent from each organization answering all questions for such complicated issues always poses the risk of measurement bias and inaccuracy. An ideal situation for future studies would be to pool and compare multiple respondents from the same organization to obtain a more comprehensive firm-level measurement. In addition, this study only surveyed and sampled biotech marketing companies in Iran. Therefore, the model should be examined using samples from other countries because the varieties of culture could have an impact on employee apprehensions. So, future researchers can test the measurement instrument in different countries and/or conduct large multi-national comparisons.

Successful marketing strategies depend very much on an organization’s ability to implement them. This paper provides an excellent study about the future of pharmaceutical KS and shows that innovation paths are linked with local and temporary occasions. Also, the results of this study provide valuable information in formulating marketing biotechnology programs. It is essential to study both economics and innovation for students and academics. The results also suggested that policies to increase economic research will also increase innovation. They could contain the consolidation of the legal framework and institutional resources for public organizations to protect intellectual properties. In general, for successful implementation of strategies an organization has to integrate KS, processes and IT.

The paper identifies the most critical factors in the innovation process of enterprizes in marketing biotechnology institutions. The implications derived from this study can shed new light upon policy-making both at the level of governance and in the management practice in Iran’s marketing biotechnology industry. Also, the paper increases understanding of the innovation process in Iran marketing biotechnology companies. This study contributes to innovating management research by offering a set of legal and dependable operational measures. These measures can help academics in theory analysis.

This is the first attempt examining the role of the learning organization, creativity and attitude to KS as a key contingency factor in innovation in Iran marketing biotechnology firms, an issue whose understanding is still developing in the literature. The paper adds to the body of knowledge by allowing better understanding the attitude toward KS and the influence of KS, learning and creativity on innovation. Previous studies did not investigate the KS in marketing biotechnology firms deeply, but, the present paper permits a more complete view on this topic. The guidelines are provided for the top directors to promote KS and innovation according to the research results. From a managerial point of view some critical elements, which are important for the success of KS and application of these elements for progressing institutional guidelines to develop KS, are considered. Theoretical foundations can be extracted from this study, and these foundations can be implemented to investigate connection in KS elements such as feasibilities processes and institution initiative abilities. So, the results could be suitable to managers when arranging an organization and shaping its culture to improve knowledge management.

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been enlightened by the behavior of ant colony's searching for food, positive feedback construction and distributed computing combined with certain heuristics are adopted in the algorithm, which makes it easier to find better solution. This paper introduces a series of ant colony algorithm and its improved algorithm of the basic principle, and discusses the ant colony algorithm application situation. Finally, several problems existing in the research and the development prospect of ACO are reviewed.

The purpose of this paper is to investigate the quality of financial reporting by banks in China, and the profit hiding behavior of banks in particular.

Reported profit is compared with actual profit using multiple regression analysis. The identification strategy allows the authors to quantify the degree of profit hiding in banking institutions.

Profit hiding exists in the whole banking sector in China regardless of the ownership structure of individual banks, though joint-stock banks have higher degree of profit hiding. Banks that are more financially constrained hide more profit than those less constrained ones. The competition in the banking industry competition impacts the extent of profit hiding, with higher competition being associated with lower degree of profit hiding.

This paper documents the prevailing behavior of profit hiding in Chinese banks. It raises issues regarding the conventional methods of measuring bank efficiencies using accounting information reported by banking institutions.

This paper empirically examines the profit hiding behavior of banks in a transitional country.

The directional solidification Fe-B alloy was prepared. The microstructures and three-body abrasive wear behaviors of directional solidification alloy were investigated.

Fe-B alloy was melted in medium frequency induction furnace. The hardness was measured on HRS-150 Rockwell-hardness tester and HXD-1000TMC tester. The wear characteristic of the alloy was examined with a block-on-ring geometry. The worn surface of the alloy was investigated by scanning electron microscopy and laser scanning microscopy.

The wear weight loss and worn surface roughness increase with the increasing contact load in wear tests. When the worn surface is perpendicular to the boride growth direction, the highest hardness plane of the boride can resist abrasive effectively under the surrounding and supporting of the martensite matrix.

The relation between boride growth direction and wear direction will cause different boride breaking tendency and wear weight loss.

The nose length is the key design parameter affecting the aerodynamic performance of high-speed maglev train, and the horizontal profile has a significant impact on the aerodynamic lift of the leading and trailing cars Hence, the study analyzes aerodynamic parameters with multi-objective optimization design.

The nose of normal temperature and normal conduction high-speed maglev train is divided into streamlined part and equipment cabin according to its geometric characteristics. Then the modified vehicle modeling function (VMF) parameterization method and surface discretization method are adopted for the parametric design of the nose. For the 12 key design parameters extracted, combined with computational fluid dynamics (CFD), support vector machine (SVR) model and multi-objective particle swarm optimization (MPSO) algorithm, the multi-objective aerodynamic optimization design of high-speed maglev train nose and the sensitivity analysis of design parameters are carried out with aerodynamic drag coefficient of the whole vehicle and the aerodynamic lift coefficient of the trailing car as the optimization objectives and the aerodynamic lift coefficient of the leading car as the constraint. The engineering improvement and wind tunnel test verification of the optimized shape are done.

Results show that the parametric design method can use less design parameters to describe the nose shape of high-speed maglev train. The prediction accuracy of the SVR model with the reduced amount of calculation and improved optimization efficiency meets the design requirements.

Compared with the original shape, the aerodynamic drag coefficient of the whole vehicle is reduced by 19.2%, and the aerodynamic lift coefficients of the leading and trailing cars are reduced by 24.8 and 51.3%, respectively, after adopting the optimized shape modified according to engineering design requirements.

This study aims to achieve long-term prediction on a specific monotonic data series of atmospheric corrosion rate vs time.

This paper presents a new method, used to the collected corrosion data of carbon steel provided by the China Gateway to Corrosion and Protection, that combines non-linear gray Bernoulli model (NGBM(1,1) with genetic algorithm to attain the purpose of this study.

Results of the experiments showed that the present study’s method is more accurate than other algorithms. In particular, the mean absolute percentage error (MAPE) and the root mean square error (RMSE) of the proposed method in data sets are 9.15 per cent and 1.23 µm/a, respectively. Furthermore, this study illustrates that model parameter can be used to evaluate the similarity of curve tendency between two carbon steel data sets.

Corrosion data are part of a typical small-sample data set, and these also belong to a gray system because corrosion has a clear outcome and an uncertainly occurrence mechanism. In this work, a new gray forecast model was proposed to achieve the goal of long-term prediction of carbon steel in China.

A perception gap refers to the differences in perception among the stakeholders regarding any aspect of the supply chain relationship. The purpose of this paper is to investigate the perception gap among service supply chain partners relating to the relative importance of key performance indicators (KPIs) and the association of this gap with service performance.

This paper presents an integrative framework that combines statistical methods and data envelopment analysis for computing perception and performance gaps, and for identifying the association between the gaps. The study follows a middle-range theorizing research approach where general inferences are induced from instances, and a theory can be developed from the observation of empirical reality.

Analysis of data from a leading global insurance service supply chain suggests that perception gap exists and can be recognised as a factor associated with performance gaps. The results suggest that the perception gap not only affects performance but can also be tracked as a meta-KPI to improve performance throughout the service supply chain.

The key implication of the presented research is that service companies can identify and resolve the differences in perceptions regarding the importance of the KPIs, by methodologically computing the gaps and tracking them as meta-KPIs.

The study extends the theoretical boundary of supply chain performance management by introducing the perception and performance gaps as novel meta-KPIs. These meta-KPIs can be computed through the integrative framework developed in the study.

This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H₂S under different temperatures, pH and salinities.

In this paper, weight loss measurements and electrochemical measurements are used to evaluate the corrosion degree of zinc and ABS A steel.

Under the conditions involved in this work, it is shown that zinc is a nice sacrificial anode with the reason of its stable potential and excellent anode current efficiency according to the relevant standard. And it is also found that the hydrogen evolution does not occur on ABS A steel specimens. The potential difference between cathode and anode is suitable; thus, it can be concluded that each steel is well protected.

To the best of the authors’ knowledge, no other study has analyzed the protection mechanism and effect of zinc as sacrificial anode in H₂S-containing environments under high temperature at present.

This study aims to construct a double layer heat insulation coating based on hollow glass microspheres (HGMs) and to investigate the effect of particle size on barrier property and heat insulation performance.

The waterborne double layer coating was composed of an anticorrosive epoxy ester primer and an HGM-containing silicone acrylic topcoat. With varied HGM sizes (20 μm, 40 μm, 60 μm and a 1:3 w/w mixture of 20 and 60 μm particles), the coating was immersed in 3.5 wt% NaCl solution for 28 days and was then subjected to a salt spray test for 450 h. The barrier properties of the coating were evaluated through electrochemical impedance spectroscopy. Heat insulation performance was examined using a self-made device.

The addition of HGMs decreased the barrier properties of the coating by creating particle/resin interfaces for water penetration. In the HGMs-containing coatings, the use of larger HGMs showed relatively good barrier properties because of the lower particle density. The coating with smaller particles yielded a higher heat insulating capacity as indicated by lower equilibrium temperatures.

Future work will be focused on improving the barrier properties of the coating. Field exposure tests should also be performed to assess the long-term performance of the coating.

The mechanical properties of the coatings in this study also implied that HGMs can be used to develop scratch-resistant and impact-resistant coatings. Other potential applications for further studies include the uses of HGMs for coatings with improved fire retardancy and electromagnetic interference shielding.

A double layer coating was developed to provide balanced performance on both anticorrosion and heat insulation. The effects of HGM size were particularly highlighted.