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Firms increasingly diversify their technological competencies to achieve different strategic objectives. This study aims to explore the impacts of technological knowledge characteristics on patenting choices for inventions created by subsidiaries in an uncertain and fast changing environment.

The data used in this study are patents granted to the world largest firms by the USPTO for inventions attributable to their subsidiaries in China between 1996 and 2005. In addition, the patent data from State Intellectual Property Office (SIPO) of China are used for the matching in terms of filing patent applications in both USA and China for a same piece of technology. A discrete Logit model is used to examine the effects of technological distance and categories on Chinese patent application and international priority.

The findings suggest that firms have priority to seek international patent protection, instead of host country protection, for valuable subsidiary inventions in their background and marginal technological fields. In addition, a firm may seek host country legal protection simultaneously for inventions built upon knowledge from technologically distant fields.

As we are more interested in protecting technological knowledge, the protection of other types of knowledge, such as organizational knowledge, deserves further research attentions. Moreover, future research may expand current study by including small and medium firms, as well as firms in other developing economies.

While the economic and legal environment in China may have evolved since studied period, the results have practical implications for firms in other developing countries that are at an early stage of catching-up or those in a host location featuring a similar uncertain and fast changing environment. In particular, the study suggests that foreign firm managers would have more strategic choices of patenting than local firms in the host country. For strategically important inventions bridging complex knowledge from different technological areas, firms could seek protection in multiple countries simultaneously, including both home country and other major markets. Furthermore, managers could choose whether or not to protect a particular category of technologies in host country depending on value of the technology to the firm and the IPR protection of host country. Finally, the approach of looking at knowledge-level characteristics, which can be easily measured through readily available intra-firm information, provides managers with a practical and useful tool to make these strategic decisions.

This study represents an effort to extend the understanding on how foreign MNCs could generate and appropriate valuable technologies in an uncertain and fast-changing environment. In particular, the authors focus on how MNCs could use different international patenting patterns to benefit from subsidiary inventions. Whereas previous literature mainly focuses on country-level and firm-level determinants, this study approaches the topic through the lens of knowledge-level factors. By studying how knowledge characteristics determine firm strategic behaviors, the authors offer additional justifications of the knowledge-based view of the firm. Meanwhile, the findings enrich our understanding of an important component of MNC’s global strategies in managing their technologies through selectively patenting in different locations. Firms pursue diversified technologies for different strategic objectives. As subsidiary inventions become a very important source of firm competitiveness, MNCs have to face the trade-off between higher patenting costs and the appropriability of subsidiary generated knowledge. The findings suggest that it is not necessary for MNCs to protect all subsidiary inventions in host countries.

The purpose of this paper is to investigate the optoelectronic properties of the multichannel ZnO UV photodetectors.

ZnO nanowires were assembled by dielectrophoresis for the UV photodetectors. Different ZnO channels were adjusted by different alternating current voltages and investigated for UV optoelectronic properties.

The number of the ZnO channels increases with the enhancing alternating current voltage. Optimum performance of the UV photodetectors is obtained with more channels.

Dielectrophoresis is a promising method for controllable assembly of multichannel ZnO photodetectors. ZnO photodetectors with more channels demonstrate a good response to 380-nm UV light, which shows great potential application in UV photodetector.

The purpose of this paper is to arrange zinc oxide (ZnO) nanowires into an appropriate position on electrodes and to research the properties of ZnO nanowires.

In this paper, dielectrophoresis (DEP) was used to fabricate ZnO nanowire devices, and the responses to temperature, ultraviolet (UV) light and breath of the device were studied.

The number of the bridged nanowires is increased with alternating current voltage. ZnO nanowires demonstrate a good photoconductivity illuminated by 365-nm UV light, and show a stable performance in monitoring unnatural breath of high frequency and low strength.

In this paper, DEP is a promising method for controllable assembly of ZnO nanowires. ZnO nanowires demonstrate a good response to 365-nm UV light and exhaled breath, which show great potential application in UV detector and medical monitor.

This paper aims to investigate the sealing characteristic of the rubber X-ring combined seal used in high-pressure hydrogen service and clarify the effect of swelling due to dissolved hydrogen on the sealing behavior.

A finite element analysis method with a user subroutine is proposed to investigate the sealing characteristic of rubber X-ring seals in conjunction with the swelling effect.

The swelling has a noticeable impact on the sealing behavior. The higher peak contact stress suggests that the X-ring seal may be superior to the O-ring seal, while the calculated increase in Mises stress suggests the X-ring exhibits a higher propensity to mechanical damage under low pressure conditions.

This paper describes a method with a user subroutine developed within ABAQUS to simulate the sealing performance coupled hydrogen swelling. The suitability of X-ring seals is evaluated. This work provides insight into the swelling effect on sealing behavior of an X-ring, which is of great value for the design and application of rubber seals used in hydrogen service.

Granular materials possess multiscale structures, i.e. micro-scales involving atoms and molecules in a solid particle, meso-scales involving individual particles and their correlated structure, and macroscopic assembly. Strong and abundant dissipations are exhibited due to mesoscopic unsteady motion of individual grains, and evolution of underlying structures (e.g. force chains, vortex, etc.), which defines the key differences between granular materials and ordinary objects. The purpose of this paper is to introduce the major studies have been conducted in recent two decades.

The main properties at individual scale are introduced, including the coordination number, pair-correlation function, force and mean stress distribution functions, and the dynamic correlation function. The relationship between meso- and macro-scales is analyzed, such as between contact force and stress, the elastic modulus, and bulk friction in granular flows. At macroscales, conventional engineering models (i.e. elasto-plastic and hypo-plastic ones) are introduced. In particular, the so-called granular hydrodynamics theory, derived from thermodynamics principles, is explained.

On the basis of recent study the authors conducted, the multiscales (both spatial and temporal) in granular materials are first explained, and a multiscale framework is presented for the mechanics of granular materials.

It would provide a paramount view on the multiscale studies of granular materials.

This study aims to address the challenge of the real-time state of charge (SOC) estimation for lithium-ion batteries in robotic systems, which is critical for monitoring remaining battery power, planning task execution, conserving energy and extending battery lifespan.

The authors introduced an optimal observer based on adaptive dynamic programming for online SOC estimation, leveraging a second-order resistor–capacitor model for the battery. The model parameters were determined by fitting an exponential function to the voltage response from pulse current discharges, and the observer's effectiveness was verified through extensive experimentation.

The proposed optimal observer demonstrated significant improvements in SOC estimation accuracy, robustness and real-time performance, outperforming traditional methods by minimizing estimation errors and eliminating the need for iterative steps in the adaptive critic and actor updates.

This study contributes a novel approach to SOC estimation using an optimal observer that optimizes the observer design by minimizing estimation errors. This method enhances the robustness of SOC estimation against observation errors and uncertainties in battery behavior, representing a significant advancement in battery management technology for robotic applications.

The suppliers of experimental resources required in megaprojects are driven by short-term interests, presuming that participation in the digital platform would only increase their inputs and fail to rapidly expand their revenue, resulting in their insufficient motivation to participate. This paper aims to design effective incentives for these suppliers exhibiting the aforementioned behaviour to drive them to participate and actively share their resources on the platform.

This paper develops incentives for applying the digital platform for experimental resource sharing by using a reverse induction approach to model and solve an incomplete information game. It compares the traditional experiment management mode and the new mode of applying the digital platform, taking the degree of sharing experimental resources on the platform as the variable and constructing three incentive models. By analysing these different degrees of sharing and the different experimental and informatisation capabilities of the suppliers, it could obtain the optimal incentive scheme for changes in sharing behaviour.

The results show that the designed incentives could increase the participation of suppliers in the platform and the number of their shared resources and make the benefits of both the supplier and the demand side reach the optimal state of a win-win situation. However, a higher degree of sharing by suppliers does not yield better results. In addition, the incentive coefficients for this degree should be set based on the suppliers’ different experimental and informatisation capabilities and the ratio of input cost-sharing, so as to avoid blind inputs from both supply and demand.

This study fills the research gap regarding incentives of the digital platform of experimental resource-sharing for megaprojects; it contributes to the body of knowledge by providing a quantitative perspective of understanding the experimental resource-sharing behaviour that motivates the usage of the digital platform. Furthermore, it reveals the incentive mechanism for application in different scenarios, and quantitative analysis is conducted to provide practical insights into promoting the new experiment management mode in megaprojects for more effective incentivisation.

This study aims to clarify the mechanism of film hole location at the span-wise direction of an internal cooling channel with crescent ribs on the adiabatic film cooling performance, three configurations are designed to observe the effects of the distance between the center of the ellipse and the side wall(Case 1, l = w/2, Case 2, l = w/3 and for Case 3, l = w/4).

Numerical simulations are conducted under two blowing ratios (i.e. 0.5 and 1) and a fixed cross-flow Reynolds number (Re_c = 100,000) with a verified turbulence model.

It is shown that at low blowing ratio, reducing the distance increases the film cooling effectiveness but keeps the trend of the effectiveness unchanged, while at high blowing ratio, the characteristic is a little bit different in the range of 0 = x/D = 10.

These features could be explained by the fact that shrinking the distance between the hole and side wall induces a much smaller reserved region and vortex downstream the ribs and a lower resistance for cooling air entering the film hole. Furthermore, the spiral flow inside the hole is impaired.

As a result, the kidney-shaped vortices originating from the jet flow are weakened, and the target surface can be well covered, resulting in an enhancement of the adiabatic film cooling performance.

This paper aims to explore the relationship between digital transformation, international competition and productivity progress by examining the dual margins of export, thereby identifying the digital development pathway for key industrial chains within the context of regional medical and health cooperation.

By constructing models incorporating both the extensive margin and intensive margin, this paper delves into the reasons underlying changes in product trade value and variety within international market competition. Utilizing export data for medical products from China to Belt and Road Initiative partner countries spanning from 2007 to 2020, an industry–destination–time panel benchmark model is established to assess the impact of digital transformation on product expansion and international competition.

The findings reveal the following insights. First, digital transformation positively impacts the intensive margin of medical products, whereas it does not exert a positive influence on the extensive margin. Second, the impact mechanism test indicates that digital transformation fosters the intensive export margin by enhancing the technical efficiency of exports but exhibits an inverted U-shaped effect on technological progress. Third, digital transformation demonstrates a notable non-linear characteristic, with a substantial increase in the lifting effect once a certain threshold is surpassed.

While previous research has extensively explored the effects of digital transformation on export trade, this study uniquely integrates the concepts of the intensive and extensive margins of export, thereby enriching the research insights derived from existing literature. It focuses on the nonlinear effects and threshold dynamics of digital transformation, particularly in relation to total factor productivity. Additionally, the paper makes a contribution to the understanding of the Health Silk Road by incorporating the health index.