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The present study assesses the impact resistance of the shear thickening fluids-filled (STFs-filled) foam through drop-hammer impact tests.

The maximum residual impact load and specific impact energy absorption rate of STF-filled foam are studied with varying thickness (4–14 mm), densities (0.35–0.6 g/cm3) and hardness (40–50 Rockwell Hardness C Scale (HRC)) under different ambient temperatures (−20−20 °C) and impact energies (25–75 J).

The following conclusions are obtained from this study: (1) the higher the impact energy, the greater the maximum residual impact force and energy absorption efficiency of the material; (2) the impact resistance of STF-filled foam can be improved with the decrease of ambient temperature, achieving the highest energy absorption rate at −10?. (3) STF-filled foam substrate has the highest impact resistance, the lowest maximum residual impact force and the highest energy absorption coefficient when the density is 0.35  g/cm3, the hardness is 45HC and the thickness is 10 mm.

This is the first paper to analyze the impact of both environmental factors and material properties on the impact resistance of STF-filled foam. The results show that the decrease in temperature and the increase in hardness can enhance the impact resistance of STF-filled foam.

The purpose of this paper is to develop a novel MEMS vector hydrophone with the key features of smaller size, better consistency, higher sensitivity and directional reception, and to develop a highly effective and economical obstacle avoidance sonar system. Currently, the typical vector hydrophones are resonant vector hydrophones based on the accelerometer, which greatly increases the volume and constrains the detection sensitivity. Also, because the system is composed of a number of devices, its size is difficult to be reduced.

A novel double T-shape MEMS vector hydrophone is proposed with a fish’s lateral line organs as prototypes. The structure size and layout location of the piezoresistors were determined by simulation analysis, and the double T-shape microstructure was fabricated integrally by MEMS manufacturing technology, after which, the acoustic package of the microstructure was completed and the prototype was produced. Finally, the packaged hydrophone was calibrated in a standing wave field in the first-class national-defense underwater acoustic calibration station of China. Also, the design and test of an obstacle avoidance sonar system based on the vector hydrophone were completed.

The calibration data show that the double T-shape vector hydrophone has a flat frequency response curve, exhibits a sensitivity of −180 dB (1 kHz, 0 dB reference 1 V/uPa) and shows a good directivity pattern in the form of an “8” shape. The test results of the obstacle avoidance sonar system further verify the feasibility of detecting underwater acoustic signals.

The next work is to increase the sensitivity by optimizing the microstructure and to realize orientation by organizing array.

The hydrophone has the advantages of smaller size, lower cost and directional reception. It can be used to develop highly effective and economical obstacle avoidance sonar system, thus solving the problems of water transport efficiency and traffic safety. The hydrophone has broad application prospects and a huge market potential in the civilian fields.

The MEMS technology and innovative bionic microstructure enable the miniaturization and low cost of the hydrophone. The hydrophone is easy to form array and can narrow the array aperture greatly. So, the hydrophone can be widely used in civil sonar systems.

The purpose of this paper is to examine the interaction effect of innovative product category and presentation order on consumer consumer’s purchasing intention and the mediating role of perceived novelty and risk perception.

The authors examined the hypotheses in three experiment studies. In Study 1, the authors primed innovative product category and presentation order on consumer consumer’s purchasing intention. In Study 2, the authors measured the mediating role of perceived novelty and risk perception. In Study 3, they validated the moderating effect of picture and text consistency on the improvement of purchase preference.

The results reveal that RNP/INP and presentation order (from whole to part/from part to whole) could enhance consumers’ purchase intention and verify the mediating role of perceived novelty and risk perception, based on which a complete internal mechanism model is constructed. The third experiment shows the moderating effect of picture and text consistency on the improvement of purchase preference by matching the category and presentation order of innovative products.

Prior literature on the thinking mode of holistic and partial processing has been mostly applied to the cognitive field of reading and text labeling. In this study, using the holistic (local) processing thinking model and anchoring theory, eye movement experiments and situational experiments, the audience’s analysis framework of information processing mechanism is constructed. The unique phenomenon of product category and overall (local) presentation order coexisting in innovative product advertisement is considered comprehensively.

This paper aims to report an insightful portable microfluidic system for rapid and selective sensing of Hg²⁺ in the picomolar (pM) concentration using microcantilever-based piezoresistive sensor. The detection time for various laboratory-based techniques is generally 12–24 h. The majority of modules used in the proposed platform are battery oriented; therefore, they are portable and handy to carry-out on-field investigations.

In this study, the authors have incorporated the benefit of three technologies, i.e. thin-film, nanoparticles (NPs) and micro-electro-mechanical systems, to selectively capture the Hg²⁺ at the pM concentration. The morphology and topography of the proposed sensor are characterized using field emission scanning electron microscopy and verification of the experimental results using energy dispersive X-ray.

The proposed portable microfluidic system is able to perform the detection in 5 min with a limit of detection (LOD) of 0.163 ng (0.81 pM/mL) for Hg²⁺, which perfectly describes its excellent performance over other reported techniques.

A microcantilever-based technology is perfect for on-site detection, and a LOD of 0.163 ng (0.81 pM/mL) is outstanding compared to other techniques, but the fabrication of microcantilever sensor is complex.

Many researchers used NPs for heavy metal ions sensing, but the excess usage and industrialization of NPs are rapidly expanding harmful consequences on the human life and nature. Also, the LOD of the NPs-based method is limited to nanomolar concentration. The suggested microfluidic system used the benefit of thin-film and microcantilever devices to provide advancement over the NPs-based approach and it has a selective sensing in pM concentration.

The purpose of this paper is to present the landscape of the cash-per-publication reward policy in China and reveal its trend since the late 1990s.

This study is based on the analysis of 168 university documents regarding the cash-per-publication reward policy at 100 Chinese universities.

Chinese universities offer cash rewards from USD30 to USD165,000 for papers published in journals indexed by Web of Science, and the average reward amount has been increasing for the past ten years.

The cash-per-publication reward policy in China has never been systematically studied and investigated before except for in some case studies. This is the first paper that reveals the landscape of the cash-per-publication reward policy in China.

Medical education was challenged and re-imagined during the COVID-19 pandemic. This study aims to examine the consequent changes in medical school curricula alongside students’ mental and physical health.

It is observed that 549 medical students (response rate: 79.7%) from 31 of 37 public medical schools in Germany completed a cross-sectional online survey. Students answered questions regarding teaching, internet use, COVID-19 and well-being. A multivariate logistic regression examined factors associated with depressed mood, insomnia and headache.

Academic teaching moved to a virtual environment (91%), whilst practical activities were suspended or cancelled (88%). Virtual teaching modality, quantity and quality were well-perceived, yet 35% of respondents were dissatisfied with their internet connection. Consequently, students worried about the pandemic’s adverse effect on their quality as a doctor (60%) and thought about postponing their studies (30%). Students were frequently engaged in the treatment of COVID-19 patients (36%). Daily screen time was significantly associated with depressed mood, insomnia and headache. Negative changes in mental and physical health were frequently observed.

Students’ experience with digital education during the COVID-19 pandemic was mixed. Whilst teaching modality, quantity and quality were well-perceived, students’ mental and physical health deteriorated. Further longitudinal studies investigating the impact of digital education on students’ well-being are necessary.

Besides teaching, faculties must quickly digitalize and strengthen social communities and offer targeted support services for students.

This is the first cross-sectional survey exploring medical students’ experience with virtual medical teaching alongside their mental and physical well-being in Germany.

The purpose of this paper is to construct a new algorithm of program procedure for medical grey relational method based on SAS software.

Based on the SAS environment, the authors construct a new algorithm of program procedure through the following methods: the construction data set, confirmation of the comparison sequence and reference sequence, the original data transformation, calculation of the grey relational coefficient of reference sequence and comparison sequence and calculating the correlation.

The results show that the novel algorithm of program procedure for medical grey relational method based on SAS software satisfies the properties properly. It also fully confirmed the biggest advantage of the grey relational analysis is that its requirements are not too high for the amount of data, and it does not need to follow the typical distribution.

The paper succeeds in constructing a novel algorithm of program procedures for medical grey relational method and providing a valuable tool for solving similar problems.

This paper aims to present the process of construction and content validity of flood disaster preparedness action (FDPA) items to measure flood preparedness characteristics and activities among the small and medium enterprises (SME).

The content validity process involved the act of conceptualization, development and validation. In short, it was implemented to develop the FDPA items that were used to measure flood preparedness at the SME level. The steps began with literature review (adopt and adapt) and judgment of expert panel on the item development process. The list of 54 items was developed. A panel of eight experts rated its content validation during a focus group discussion.

In total, 52 items were acceptable to be passed on to the next stage of data collection. The items content validity (I-CVI) measurement of the items was within an acceptable range of more than 0.75, except for two items: Q38 and Q39. The scale content validity (S-CVI) value gave an excellent score of 0.95. Several items with low I-CVI score values for relevancy and clarity were subject to modification.

Content validity ensured accurate interpretations of results. To support the construct validity of an instrument, documenting findings from content validity was essential.

This paper demonstrated the initial phase of scale development on FDPA items. This newly developed item allows the integration of several flood disaster preparedness activities construct by review and judgment process by the panel of experts in the field.

The development of an effective corporate vision is a necessary issue for corporate performance, and it is a key issue for corporate sustainable development as well. The recognition of questions like “what is the role of corporate vision in corporate performance” is directly related to the attitude and practice of entrepreneurs and managers toward the development of corporate vision as well as the effectiveness of the corporate vision itself. To better answer the questions concerning the role of corporate vision development and effectively guide the practice of corporations, the authors study the pathways and mechanisms by which corporate visions operate to assist businesses in achieving high performance.

The article completes the construction of indicators to measure each dimension of the corporate vision in line with social cognitive theory and analyzes the relationship between corporate vision and corporate performance by combining qualitative comparative analysis (QCA) and necessary condition analysis (NCA) research methods. The article provides insights into the logic of constructing and adjusting corporate visions from a process perspective.

The mechanisms by which corporate visions can be articulated, accepted and transformed within the organization are also the means by which corporate visions can improve corporate performance. In a dynamic environment, the corporate vision setting and acceptance process integrates the requirements of various stakeholders, leading to the adjustment and acceptance of the corporate vision. As a result, the vision has continuous validity in a changing environment. Both start-ups and non-start-ups can benefit from the guidance provided by a strong corporate vision in overcoming a variety of issues and obstacles to produce strong business performance.

This is the first study that shows the relationship between corporate vision and corporate performance from a process perspective. The authors are interested in understanding which characteristics for building a corporate vision are more accepted by organizational members and, in turn, create high corporate performance. The authors also explore the conditions for corporate vision acceptance. This research has positive implications for shedding some light on the mechanisms by which corporate visions improve corporate performance.

The use of digital technology in firms has drawn attention of innovation management scholars and policy-makers, especially the imitation of digital technology and competition among peer firms. Drawing on dynamic competition theory, this paper examines how firms react to their peers' digital innovation behavior and the effect of external environment mechanisms on the magnitude of peer effects.

This paper utilizes a text mining method to construct a baseline model with a Tobit estimator using data obtained for Chinese listed firms.

The findings suggest that peer effects on digital innovation behavior are robust and significant positive in China. Moreover, peer effects on digital innovation participation are positively magnified by firms' strong social network and high Fintech development. However, peer effects are relatively higher in non-state-owned enterprises (non-SOEs), low-profitability and high R&D firms.

The authors' findings contribute to the digital management literature by showing that firms need digital technological imitation and diffusion of innovations in the digital era.

Managers should provide insights into firms' imitation of their peers' acts to preserve competitive parity. Besides, firms should integrate employees within the organization and communicate digital innovation concepts and behaviors to external peer firms.

First, this paper contributes to explaining how firms change their digital innovation strategy through the influence of peers' digital innovation behavior. Second, this paper fills the literature gaps related to the moderating effects of external environment factors in peer effects of digital innovation behavior.