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The purpose of this paper is to prepare a new modified polybutylene terephalate (MPBT) for fused deposition modeling (FDM) to increase the variety of materials compatible with printing. And the printing materials can be used to print components with a complex structure and functional mechanical parts.

The MPBT, poly(butylene terephalate-co-isophthalate-co-sebacate) (PBTIS), was prepared for FDM by direct esterification and subsequent polycondensation using terephthalic acid (PTA), isophthalic acid (PIA), sebacic acid (SA) and 1,4-butanediol (BDO). The effects of the content of PIA (20-40 mol%) on the mechanical properties of PBTIS were investigated when the mole per cent of SA (α_SA) is zero. The effects of α_SA (0-7mol%) on the thermal, rheological and mechanical properties of PBTIS were investigated at n_PTA/n_PIA = 7/3. A desktop wire drawing and extruding machine was used to fabricate the filaments, whose printability and anisotropy were tested by three-dimensional (3D) printing experiments.

A candidate content of PIA introducing into PBT was obtained to be about 30 per cent, and the Izod notched impact strength of PBTIS increased with the increase of α_SA. The results showed that the PBTIS (n_PTA/n_PIA = 7/3, α_SA = 3-5mol%) is suitable for FDM.

New printing materials with good Izod notched impact strength were obtained by introducing PIA and SA (n_PTA/n_PIA = 7/3, α_SA = 3-5 mol%) into PBT and their anisotropy are better than that of ABS.

This paper aims to gain a clear understanding of the ventilated cavity evolution around an NACA0015 hydrofoil by using both experimental and numerical investigation.

The bubble evolution around an NACA0015 hydrofoil with or without air injection was observed in a water tunnel, and the simulation was conducted using a modified turbulence model and homogeneous cavitation model.

The present simulation method can successfully predict the bubble evolutions around the NACA0015 hydrofoil with or without air injection. Air injection can alleviate the nature cavitation oscillation, and the suppression effect on nature cavitation depends on the air-entrant coefficient. It is confirmed that the air and vapor cavity have the same shedding frequency. It is seen that the air sheet closely attaches to the hydrofoil surface and is surrounded by the vapor sheet. Thus, the injected air promotes vapor growth and results in an increase in the cavity shedding frequency. Further, with a large air-entrant coefficient, the pressure fluctuation is suppressed completely.

The new simulation method is adopted to explore the mechanism of ventilated cavitation. The bubble evolutions with and without air injection have been comprehensively studied by experimental and numerical investigation. The effects of air injection on natural cavity oscillations and pressure fluctuations have been revealed in the present study.

The purpose of this report is to demonstrate open and distance education (ODE) can support poverty alleviation. Taking the practices of the Open University of China (the OUC) as an example, this paper aims to reveal how open universities make contributions to local residents in rural and remote areas.

Focusing on 25 poverty-stricken counties, the OUC had invested 58 million RMB to its learning centers in these counties from 2017 to 2020. The first one is to improve ICT and educational facilities in these learning centers. The second approach is to cultivate local residents with degree programs through ODE so as to promote local economic development. The third one is to design and develop training programs according to local context to meet the specific needs of local villagers.

After 3 years working, cloud-based classrooms and computer rooms have been set up. Bookstores have been founded and printed books have been donated. Hundreds of thousands of digital micro lectures have been supplied to these learning centers which have been improved and fully played their functions. Nearly 50,000 local residents have been directly benefited. Village leaders have helped lift local residents out of poverty. Poverty-stricken villagers have been financed to study on either undergraduate or diploma programs. Local residents have improved their skills by learning with the training programs offered by the OUC.

ODE is proved to be an effective way to eradicate poverty. Open universities are proved to be able to make contributions to social justice. By fulfilling its commitments to eliminate poverty within the national strategy framework, the OUC has built its brand nationwide.

According to the real environment of China, the authors collect micro data about Chinese family firms (FFs) to explain why some Chinese FFs still tend to introduce external managers though they have to face governance conflict between family-based managers and external managers.

This study analyzes the effect of governance conflict between family-based managers and external managers on firm performance by using ordinary least square test, which is also used to test which factor has influence on governance conflict’s profit promotion effect.

This study finds that governance conflict significantly improves firm performance (profit promotion effect). The governance conflict caused by the introduction of external managers in Chinese FFs can significantly improve a firm’s performance by raising its management efficiency and capital investment.

The governance conflict of the family business needs to be further refined in following research. Besides, this study is only based on the empirical study of cross-section data.

Different from the existing related research is mainly based on the sample data of listed family enterprises, the China employer-employee matched survey data includes a large number of small and medium-sized FFs, and has obtained the actual situation of how many of the middle and senior managers are external not family members.

At present, the rural folk ecotourism has been paid attention to by the public, so it is inevitable to analyze the architectural planning and design of folk ecotourism. Based on this, in this article, an analysis of the architectural planning and design for the protective development of rural folk custom ecotourism was proposed. First of all, the development background of folk custom ecotourism was briefly analyzed; then, the research status of ecotourism was expounded; next, the planning and design of rural folk tourism were put forward, and the essentials of architectural planning and design were analyzed; with specific rural folk custom ecotourism projects as examples, the planning and design were carried out; in addition, caves, temples, roads and other buildings were analyzed emphatically. These measures can provide references for the architectural planning of folk custom tourism.

This scoping review article examined research on information behavior in communities over the past two decades (2000–2023). The review aims to uncover the characteristics and types of communities studied, the featured information behaviors, and the research methods employed.

The PRISMA-ScR guidelines were followed to conduct this review. Five databases were selected to search for relevant empirical research. A total of 57 studies met the inclusion criteria for review. Thematic synthesis was used to analyze the multidimensional findings of included studies.

A steady increase in the number of articles is evident in the past two decades. The review suggests that information behavior in community studies involved collaboration from other disciplines, such as public health and business management. More than half of the communities studied are virtual communities (56.1%), followed by communities of identity, professional communities and support communities, communities of interest, geographic communities, and academic communities. There are overlaps among these categories. Information sharing (63.2%) and information seeking (57.9%) were the most studied behavior of communities, followed by information use, information needs, and information judgment. Questionnaires (38.6%) and interviews (35.1%) were the most commonly used data collection techniques in studying information behavior in communities. It is noteworthy that eleven (19.3%) mentioned utilizing community-engaged approaches.

This is the first scoping review to explore the intersecting constructs of community research and information behavior studies. We call for further research to understand the contextual factors that shape the community’s information environments and to increase awareness of the partnership between communities and researchers.

The purpose of this study is to investigate the application of non-destructive testing methods in measuring bearing oil film thickness to ensure that bearings are in a normal lubrication state. The oil film thickness is a crucial parameter reflecting the lubrication status of bearings, directly influencing the operational state of bearing transmission systems. However, it is challenging to accurately measure the oil film thickness under traditional disassembly conditions due to factors such as bearing structure and working conditions. Therefore, there is an urgent need for a nondestructive testing method to measure the oil film thickness and its status.

This paper introduces methods for optically, electrically and acoustically measuring the oil film thickness and status of bearings. It discusses the adaptability and measurement accuracy of different bearing oil film measurement methods and the impact of varying measurement conditions on accuracy. In addition, it compares the application scenarios of other techniques and the influence of the environment on detection results.

Ultrasonic measurement stands out due to its widespread adaptability, making it suitable for oil film thickness detection in various states and monitoring continuous changes in oil film thickness. Different methods can be selected depending on the measurement environment to compensate for measurement accuracy and enhance detection effectiveness.

This paper reviews the basic principles and latest applications of optical, electrical and acoustic measurement of oil film thickness and status. It analyzes applicable measurement methods for oil film under different conditions. It discusses the future trends of detection methods, providing possible solutions for bearing oil film thickness detection in complex engineering environments.

This paper aims to study the learning-by-exporting effect among small-to-medium-sized enterprises (SMEs). Specifically, the authors propose a dynamic perspective and suggest that learning-by-exporting is duration-dependent and contingent upon the born global internationalization strategy. In earlier phases of export activities, exporting has had a strong positive effect on SMEs’ innovations, which, however, diminishes over time. This inverted U-shape effect is even more distinct for born global firms.

The authors used longitudinal data with 1,689 Canadian SMEs to test their hypotheses. A two-stage instrumental approach is used to take into account the endogeneity of the born global international strategy on new product innovations.

Born globals learn faster at the early stages of exporting but also restrain their innovations more strongly than gradual internationalizers in the longer run, leveling out the initial learning advantages of newness. Thus, this study suggests that born globals have a significantly different learning trajectory than gradual internationalizers.

To maximize the benefits of exporting on innovation, managers should focus on learning during the initial years of exporting. However, once this period has passed, it is advisable for managers to invest in research and development as well as other innovation activities to complement the learning effect of exporting. Born global firms experience more rapid learning at the initial stage of exporting, but such learning effects wear off quicker later than gradually internationalized firms. For SME managers, this study helps draw their attention to the learning benefits of exporting in the initial years of export participation.

This study corroborates recent studies arguing for a “learning-by-exporting” effect. Providing longitudinal firm-level evidence, the authors also forward a dynamic perspective and show that learning by exporting is duration dependent and contingent upon the market entry strategy pursued by SMEs.

The purpose of this paper is to analyze the effects of public investment in agricultural R&D and extension on broadacre farming productivity in Australia.

An autoregressive integrated moving average (ARIMA) regression model is applied to estimate the effects of public investment in agricultural R&D and extension on Australian braodacre productivity.

The study reveals that public investment in agricultural R&D and extension has contributed almost two-thirds of average annual broadacre productivity growth between 1952-1953 and 2006-2007, the average internal rate of return to public investment in agricultural R&D and extension was 28.4 and 47.5 per cent a year, respectively, and overseas spill-ins is an important source of domestic agricultural productivity growth.

Policy implications: the findings suggest that increasing public investment in agricultural R&D and extension and maintaining agricultural R&D policy stability are equally important to have a sustained long-term agricultural productivity growth, and maintaining an open trade and investment regime is important to benefit from foreign knowledge spillovers which is especially important for developing countries.

This paper contributes to the existing literature by employing more sophisticated econometric techniques with an extended data set for the period from 1952-1953 to 2006-2007. The study separates the contribution of public R&D investment and the extension investment, and also takes into account the contribution of overseas public investment on the TFP growth in the Australian broadacre sector.

Traditional case-adaptation methods have poor accuracy, low efficiency and limited applicability, which cannot meet the needs of knowledge users. To address the shortcomings of the existing research in the industry, this paper proposes a case-adaptation optimization algorithm to support the effective application of tacit knowledge resources.

The attribute simplification algorithm based on the forward search strategy in the neighborhood decision information system is implemented to realize the vertical dimensionality reduction of the case base, and the fuzzy C-mean (FCM) clustering algorithm based on the simulated annealing genetic algorithm (SAGA) is implemented to compress the case base horizontally with multiple decision classes. Then, the subspace K-nearest neighbors (KNN) algorithm is used to induce the decision rules for the set of adapted cases to complete the optimization of the adaptation model.

The findings suggest the rapid enrichment of data, information and tacit knowledge in the field of practice has led to low efficiency and low utilization of knowledge dissemination, and this algorithm can effectively alleviate the problems of users falling into “knowledge disorientation” in the era of the knowledge economy.

This study provides a model with case knowledge that meets users’ needs, thereby effectively improving the application of the tacit knowledge in the explicit case base and the problem-solving efficiency of knowledge users.

The adaptation model can serve as a stable and efficient prediction model to make predictions for the effects of the many logistics and e-commerce enterprises' plans.

This study designs a multi-decision class case-adaptation optimization study based on forward attribute selection strategy-neighborhood rough sets (FASS-NRS) and simulated annealing genetic algorithm-fuzzy C-means (SAGA-FCM) for tacit knowledgeable exogenous cases. By effectively organizing and adjusting tacit knowledge resources, knowledge service organizations can maintain their competitive advantages. The algorithm models established in this study develop theoretical directions for a multi-decision class case-adaptation optimization study of tacit knowledge.