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This study aims to examine how evolutionary and ecological forces shape the market strategy and performance of firms after their organizational form was changed by exogenous shock.

Hypotheses are developed based on both evolutionary and ecological perspectives and tested using fixed effect logistics models and a sample of 3,110 firms that were privatized during 1998–2007.

I find that once the organizational form of firms is changed, the market strategy of organizations is shaped by the population density of their old and new organizational forms in their existing market. Moreover, such a market strategy enhances the survival chance of firms.

This study contributes to organizational evolution literature by unpacking the evolution process when exogeneous shock to organizational form takes place. It advances both evolutionary economics and organization ecology theory through integrating them to understand the evolution process of organizations. This study also contributes to the privatization literature through examining the ecological forces that shape the restructuring strategy of firms after privatization and the performance implications of such restructuring.

The purpose of this paper is to study the condensation flow of wet steam in the last stage of a steam turbine and to obtain the distribution of condensation parameters such as nucleation rate, Mach number and wetness.

Because of the sensitivity of the condensation parameter distribution, a double fluid numerical model and a realizable k-ε-k_d turbulence model were applied in this study, and the numerical solution for the non-equilibrium condensation flow is provided.

The simulation results are consistent with the experimental results of the Bakhtar test. The calculation results indicate that the degree of departure from saturation has a significant impact on the wet steam transonic condensation flow. When the inlet steam deviates from the saturation state, shock wave interference and vortex mixing also have a great influence on the distribution of water droplets.

The research results can provide reference for steam turbine wetness losses evaluation and flow passage structure optimization design.

Big data analytics (BDA) and machine learning (ML) can be used to identify the influencing factors of online service supply chains (OSSCs) and can help in the formulation of optimal pricing strategies. This paper analyzes the influencing factors of customer online shopping from the demand-side perspective and formulates optimal pricing strategies from the supply-side perspective.

This paper uses ML and the Stackelberg game approach to discuss OSSC management. ML's feature selection algorithm is used to identify the important influencing factors of 12,330 customers' online shopping intention data using four different classifiers. The Stackelberg game approach is used to analyze the pricing strategies of integrators and suppliers in OSSCs.

First, the feature selection algorithm can improve the efficiency of optimization in big data samples of OSSCs. Second, the level of visualization and the quality of information (page value) will affect the purchase behavior of customers. Finally, the relationship between the optimal pricing and the level of visualization is obtained through the Stackelberg game approach.

This paper reveals the phenomenon of “mystery customers,” and the results of this paper can provide insights and suggestions regarding the decision-making behavior of integrators and suppliers in OSSC management.

Considering customer behavior intention, this paper uses a data-driven method to explore the influencing factors and pricing strategies of OSSCs. The empirical results enrich the existing OSSC management research, proposing that the level of product visualization and information quality plays an important role in OSSCs.

The purpose of this study is to improved the efficiency of condensing steam turbines by legitimately reforming the flow structure. It is of great significance to study the condensation flow characteristics of wet steam for optimizing the operation of condensing steam turbines.

A two-fluid model was used to study the wet steam flow in a stator cascade. The effects of the inlet temperature and pressure drop on the cascade performance were analyzed. On this basis, endwall protrusion models were set up at varied axial position on the pressure surface to evaluate the wetness control and loss under different design conditions for cascade optimization.

The analysis indicates that increasing the inlet temperature or decreasing the pressure drop can effectively control the steam wetness but increase the droplet radius. The increasing inlet temperature can delay the condensation and alleviate the deterioration of the aerodynamic performance of cascades. The non-axisymmetric endwall can significantly affect the distribution of steam parameters below its height and slightly reduce the droplet radius. Compared with the original stator cascade, the optimum design conditions reduce the steam wetness by 8.07 per cent and the total pressure loss by 6.91 per cent below a 20 per cent blade height.

These research results can serve as a reference for condensing steam turbine wetness losses evaluation and flow passage optimization design.

The flow state of wet steam will affect the thermodynamic and aerodynamic characteristics of steam turbine. The purpose of this study is to effectively control the wetness losses caused by wet steam condensation, and hence a cascade of 600 MW steam turbine was taken as the research object.

The influence of blade surface roughness on the condensation characteristics was analyzed, and the dehumidification mechanism and wetness control effect were obtained.

With the increase of blade surface roughness, the peak nucleation rate decreases gradually. According to the Mach number distribution on the blade surface, there is a sensitive region for the influence of roughness on the aerodynamic performance of cascade. The sensitive region of nucleation rate roughness should be between 50 and 150 µm.

The increase of blade surface roughness will increase the dynamic loss in cascade, but it can reduce the thermodynamic loss caused by condensation to a certain extent.

This study aims to analyze the shear strength and fracture mechanism of full Cu-Sn IMCs joints with different Cu₃Sn proportion and joints with the conventional interfacial structure in electronic packaging.

The Cu-Sn IMCs joints with different Cu₃Sn proportion were fabricated through soldering Cu-6 μm Sn-Cu sandwich structure under the extended soldering time and suitable pressure. The joints of conventional interfacial structure were fabricated through soldering Cu-100 μm Sn-Cu sandwich structure. After the shear test was conducted, the fracture mechanism of different joints was studied through observing the cross-sectional fracture morphology and top-view fracture morphology of sheared joints.

The strength of joints with the conventional interfacial structure was 26.6 MPa, while the strength of full Cu-Sn IMCs joints with 46.7, 60.6, 76.7 and 100 per cent Cu₃Sn was, respectively, 33.5, 39.7, 45.7 and 57.9 MPa. The detailed reason for the strength of joints showing such regularity was proposed. For the joint of conventional interfacial structure, the microvoids accumulation fracture happened within the Sn solder. However, for the full Cu-Sn IMCs joint with 46.7 per cent Cu₃Sn, the cleavage fracture happened within the Cu6Sn5. As the Cu₃Sn proportion increased to 60.6 per cent, the inter-granular fracture, which resulted in the interfacial delamination of Cu₃Sn and Cu6Sn5, occurred along the Cu₃Sn/Cu6Sn5 interface, while the cleavage fracture happened within the Cu6Sn5. Then, with the Cu₃Sn proportion increasing to 76.7 per cent, the cleavage fracture happened within the Cu6Sn5, while the transgranular fracture happened within the Cu₃Sn. The inter-granular fracture, which led to the interfacial delamination of Cu₃Sn and Cu, happened along the Cu/Cu₃Sn interface. For the full Cu₃Sn joint, the cleavage fracture happened within the Cu₃Sn.

The shear strength and fracture mechanism of full Cu-Sn IMCs joints was systematically studied. A direct comparison regarding the shear strength and fracture mechanism between the full Cu-Sn IMCs joints and joints with the conventional interfacial structure was conducted.

Mobile marketing, the two- or multi-way communication and promotion of an offer between a firm and its customers using a mobile medium, device, platform, or technology, has made rapid strides in the past several years. Mobile marketing has entered its second phase or Mobile Marketing 2.0. The surpassing of desktop by mobile devices in digital media consumption, diffusion of wearable devices among customers, and an overall integration and interconnectedness of devices characterize this phase. Against this backdrop, we present a synthesis of the most recent literature in mobile marketing. We discuss three key advances in mobile marketing research relating to mobile targeting, personalization, and mobile-led cross-channel effects. We outline emerging industry trends in mobile marketing, including mobile app monetization, augmented reality, data and privacy, wearable devices, driverless vehicles, the Internet of Things, and artificial intelligence. Within each extant and emerging area, we delineate the future research opportunities in mobile marketing. Finally, we discuss the impact of mobile marketing on customer, firm, and societal outcomes.

This study aims to investigate the effect of ultrasound on interfacial microstructures and growth kinetics of intermetallic compounds (IMCs) at different temperatures.

To investigate the effect of ultrasound on IMCs growth quantitatively, the cross-sectional area of IMCs layers over a confirmed length was obtained for calculating the thickness of the IMCs layer.

The generation of dimensional difference in normal direction between Cu₆Sn₅ and its adjacent Cu₆Sn₅, formation of bossed Cu₆Sn₅ and non-interfacial Cu₆Sn₅ in ultrasonic solder joints made the interfacial Cu₆Sn₅ layer present a non-scallop-like morphology different from that of traditional solder joints. At 260°C and 290°C, the Cu₃Sn layer presented a wave-like shape. In contrast, at 320°C, the Cu₃Sn in ultrasonic solder joints consisted of non-interfacial Cu₃Sn and interfacial Cu₃Sn with a branch-like shape. The Cu₆Sn₅/Cu₃Sn boundary and Cu₃Sn/Cu interface presented a sawtooth-like shape under the effect of ultrasound. The predominant mechanism of ultrasonic-assisted growth of Cu₆Sn₅ growth at 260°C, 290°C and 320°C involved the grain boundary diffusion accompanied by grain coarsening. The Cu₃Sn growth was controlled by volume diffusion during the ultrasonic soldering process at 260°C and 290°C. The diffusion mechanism of Cu₃Sn growth transformed to grain boundary diffusion accompanied by grain coarsening when the ultrasonic soldering temperature was increased to 320°C.

The microstructural evolution and growth kinetics of IMCs in ultrasonically prepared ultrasonic solder joints at different temperatures have rarely been reported in previous studies. In this study, the effect of ultrasound on microstructural evolution and growth kinetics of IMCs was systematically investigated.

The purpose of this paper is to propose an simple and efficient stiffness model for line contact under elastohydrodynamic lubrication (EHL) and to investigate the gear meshing stiffness by the proposed model.

The method combines the surface contact stiffness and film stiffness as EHL contact stiffness. The EHL contact stiffness can be calculated by the external load and displacement of the load action point. The displacement is the sum of deformation of the film and contact surface and is equal to the distance of the mutual approach of two contact bodies.

The conclusion is drawn that the contact stiffness calculated by the proposed model is smaller than that by the minimum film model and larger than that by the mean film model. It is also concluded that the gear meshing stiffness under EHL is slightly smaller than that under dry contact.

The EHL contact stiffness can be obtained by the increment of external load and mutual approach directly. The calculation of oil film stiffness and surface contact stiffness separately is avoided.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0465

According to the requirements of servicing and deorbiting the failure satellites, especially the tumbling ones on geosynchronous orbit, this paper aims to design a docking mechanism to capture these tumbling satellites in orbit, to analyze the dynamics of the docking system and to develop a new collision force-limited control method in various docking speeds.

The mechanism includes a cone-rod mechanism which captures the apogee engine with a full consideration of despinning and damping characteristics and a locking and releasing mechanism which rigidly connects the international standard interface ring (Marman rings, such as 937B, 1194 and 1194A mechanical interface). The docking mechanism was designed under-actuated, aimed to greatly reduce the difficulty of control and ensure the continuity, synchronization and force uniformity under the process of repeatedly capturing, despinning, locking and releasing the tumbling satellite. The dynamic model of docking mechanism was established, and the impact force was analyzed in the docking process. Furthermore, a collision detection and compliance control method is proposed by using the active force-limited Cartesian impedance control and passive damping mechanism design.

A variety of conditions were set for the docking kinematics and dynamics simulation. The simulation and low-speed docking experiment results showed that the force translation in the docking phase was stable, the mechanism design scheme was reasonable and feasible and the proposed force-limited Cartesian impedance control could detect the collision and keep the external force within the desired value.

The paper presents a universal docking mechanism and force-limited Cartesian impedance control approach to capture the tumbling non-cooperative satellite. The docking mechanism was designed under-actuated to greatly reduce the difficulty of control and ensure the continuity, synchronization and force uniformity. The dynamic model of docking mechanism was established. The impact force was controlled within desired value by using a combination of active force-limited control approach and passive damping mechanism.