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This study aims to further study the fire resistance of prefabricated concrete beam-column joints with end-plate connection. This paper aims to analyze the fire resistance of this joint in prefabricated reinforced concrete frame structure (PRCS).

First, the accuracy of the model is verified by using the test data. Based on this, a refined finite element model of PRCS structure with two stories and two spans is established. The influence of four working conditions with different fire floors (positions) and different axial compression ratios on the deformation, failure and fire resistance of PRCS structure are analyzed.

The results show that under the four working conditions, the fire resistance of the PRCS structure under Condition 1 and Condition 2 is smaller. It shows that the beam deformation develops slowly in PRCS structure under four kinds of fire positions, and the large displacement emerges 60 min later, which is poles apart from that of prefabricated beam column members. With the increase of the fire time, the material is damaged and deteriorated, which leads to the eccentricity of the axial load, so that the column top appears large lateral displacement. Under the Conditions 1 and 3, the lateral displacement of the column gradually decreases as the axial compression ratio rises.

It is found that there is a distinct lack of researching on the fire resistance of prefabricated joints, and the existed research studies are limited to the fire resistance of members. Thus, it is necessary to strengthen the first floor and side column design of prefabricated frame structure.

The authors empirically examined the theoretically recognized industrial linkages between manufacturing and services from the trade perspective. In particular, they confirmed the trade effect of manufacturing on services, given that global value chain fragmentation pervades and splits manufacturing and services segments separately in developed and developing countries.

Based on observations of 47 countries with manufacturing and service trade data from 1990 to 2020 and with gravity model specification, the authors primarily used the Poisson pseudo-maximum likelihood (PPML) estimation with multiple levels of fixed effects. Considering that many zero values are included in the dependent variable and potential endogeneity, other methods such as Tobit regression, Heckman estimation and two-stage least squares estimation (2SLS) are used. Subsample estimation also supplemented the empirical research.

The results showed that manufacturing trade is a stepping-stone rather than an obstacle to service trade. This finding exhibited significant robustness under different model specifications, instrumental variable estimation and subsample checks. Moreover, in contrast to the north–north country ties, manufacturing trade between northern and southern countries has played a prominent stepping-stone role; meanwhile, manufacturing trade among core–peripheral countries has a considerably more significant impact than the outcomes of core–core and peripheral–peripheral countries.

The authors provided direct clarification and revealed that trade in manufacturing remains the demand basis for service trade. As trade in manufacturing and services are typical phenomena of transnational production linkages, the authors suggested exploring the underlying role of global value chain (GVC) fragmentation and the offset and even barrier effect of biased institutional arrangements on GVC fragmentation.

Concrete-filled steel tube structures are widely used for their high bearing capacity, good plasticity, good fire resistance and optimal seismic performance. In order to give full play to the advantages of concrete-filled steel tube, this paper proposes a prefabricated concrete-filled steel tube frame joint.

The concrete-filled steel tube column and beam are connected by high-strength bolted end-plate, and the steel bars in the concrete beam are welded vertically with the end-plates through the enlarged pier head. In addition, the finite element software ABAQUS is used numerically to study the seismic performance of the structure.

The ductility coefficient of the joint is in 1.72–6.82, and greater than 2.26 as a whole. The equivalent viscous damping coefficient of the joint is 0.13–3.03, indicating that the structure has good energy dissipation capacity.

The structure is convenient for construction and overcomes the shortcomings of the previous on-site welding and on-site concrete pouring. The high-strength bolted end-plate connection can effectively transfer the load, and each component can give play to its material characteristics.

Emotional intelligence (EI) is deemed important in developing interpersonal relationships. However, in the development of team-member exchange (TMX), the effect of EI on TMX and the team context have been largely ignored. For filling these gaps, this study explores the effect of employee EI on employee TMX and introduces EI-based leader-member exchange (LMX) differentiation as a team context to moderate the EI-TMX relationship.

Data were drawn from 51 teams (consisting of 293 followers and 51 team leaders) selected from 30 companies (across the industries of technology, real estate, commerce and manufacturing).

Results revealed that employee EI was positively related to employee TMX. EI acted as the basis of LMX differentiation (EI was positively related to LMX, EI variety was positively associated with LMX differentiation), and EI-based LMX differentiation acted as a favorable context for high-EI employees to develop high-quality TMX.

This study contributes to the understanding of EI’s significant and complex influence on interpersonal exchange relationships between leaders, followers and coworkers.

The purpose of this study is to put forward a high-strength bolt end-plate connection of prefabricated concrete beam-column joint and carry out the pseudo-static test.

ABAQUS finite element software is used to study the fire resistance performance of high-strength bolt end-plate prefabricated joint. This mainly considers the influence of axial compression ratio, screw preload, end-plate thickness and steel hoop thickness.

The results show that the thickness of end-plate and steel hoop has a certain effect on the fire resistance. The change of screw preload has little effect on the fire resistance limit. Compared with the cast-in-place concrete beam-column joint, the deformation trend of column-beam end of the fabricated joint is basically the same as that of cast-in-place joint.

To study the mechanical performance of this kind of joint more comprehensively, the finite element software is used to study the prefabricated concrete beam-column joint with end-plates, and the effects of axial compression ratio, screw preload, end-plate thickness and steel hoop thickness on the fire resistance of joints are mainly considered.

This paper aims to present a novel fault estimator design scheme, in order to improve the practicability of the fault estimation.

The paper first transforms the system state into three parts. Then a reduced‐observer is designed for an unknown input and fault‐free system, and the observer can get no bias error in the state estimation. So the estimator can get the exact estimation for the unknown input and fault of the actuator.

By using this approach it is found that the condition of the estimator is weaker than other observers. It is a qualified and simple and straightforward approach to be applied in wide domains.

It should be noted that the sensors should be perfectly reliable. The maximum number of disturbances which can be decoupled cannot be larger than the number of independent actuators.

It is a very useful approach to solve the problem that the actuator is contaminated by disturbances.

The paper uses a transformation to divide the state into three parts. By estimating the part that is not affected by the disturbance and fault, it gets the exact estimation for the unknown input and fault of the actuator. The design condition of the reduced‐order observer which is proposed is weaker than others.

The purpose of this paper is to develop Triple Finite Volume Method (tFVM), the author discretizes incompressible Navier-Stokes equation by tFVM, which leads to a special linear system of saddle point problem, and most computational efforts for solving the linear system are invested on the linear solver GMRES.

In this paper, by recently developed preconditioner Hermitian/Skew-Hermitian Separation (HSS) and the parallel implementation of GMRES, the author develops a quick solver, HSS-pGMRES-tFVM, for fast solving incompressible Navier-Stokes equation.

Computational results show that, the quick solver HSS-pGMRES-tFVM significantly increases the solution speed for saddle point problem from incompressible Navier-Stokes equation than the conventional solvers.

Altogether, the contribution of this paper is that the author developed the quick solver, HSS-pGMRES-tFVM, for fast solving incompressible Navier-Stokes equation.

The purpose of this paper is to improve data transmission efficiency in a P2P system.

This mechanism does not require changing existing mesh topology, and only necessary peers' evaluation mechanisms need to be introduced.

This paper presents a data reservation mechanism so that it can transmit data via the push and pull model on the P2P live stream system with the mesh topology. The experiment result of establishing a simulation environment reveals that the above mentioned is an effective way of reducing the data transmission delay by 40 per cent.

To improve data transmission efficiency in a P2P system, this paper presents a data reservation mechanism so that it can transmit data via the push and pull model on the P2P live stream system with the mesh topology.

The purpose of this study satisfied the need for rapid, sensitive and highly portable identification of an explosion gas. In our study, a battery-operated, low-cost and portable gas detection system consisting of a cataluminescence-based sensor array was developed for the detection and identification of explosion gas. This device shows how the discriminatory capacity of sensor arrays utilizing pattern recognition operate in environments.

A total of 25 sensor units, including common metal oxides and decorated materials, have been carefully selected as sensing elements of 5 × 5 sensor array. Dynamic and static analysis methods were utilized to characterize the performance of the explosion gas detection system to five kinds of explosion gases. The device collects images of chemical sensors before and after exposing to the target gas and then processes those images to extract the unique characteristic for each gas. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used to analyze the image patterns.

Our study demonstrated that the portable gas detection device shows promising perspective for the recognition and discrimination of explosion gas. It can be used for the olfactory system of robot made by integrating the electronic nose and computer together.

The device collects images of chemical sensors before and after exposing to the target gas and then processes those images to extract the unique characteristic for each gas. HCA and (PCA were used to analyze the image patterns. Our study demonstrated that the portable gas detection device shows promising perspective for the recognition and discrimination of explosion gas. It can be used for olfactory system of robot made by integrating the electronic nose and computer together.

This paper aims to build a theory model to examine the influencing mechanism of entrepreneurial environment on new firm performance based on network view and resource‐based view, and then carry out empirical research.

Data were obtained from 112 new firms, through the use of questionnaires, in Changchun city, China.

Evidence indicates that the entrepreneurial environment has an impact on new firm performance through entrepreneurial network and resource acquisition. The results show that eight out of ten hypotheses are supported.

In a hostile, dynamic and complex environment, the new firm should enhance its entrepreneurial network to ensure resource acquisition and then promote performance.

The paper shows definitely the significance of entrepreneurial network as a bridge between external environment and resource acquisition and new firm performance. Entrepreneurial network and resource acquisition are identified as important intermediary variables, and resource combination ability as a moderating variable. This paper examines the influence of external environment on new firm performance. The research has some theoretical and managerial implications for new firms' survival and obtaining growth in highly uncertain and turbulent environments.