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The smart image sensor (SIS) which integrated with both sensor and smart processor has been widely applied in vision-based intelligent perception. In these applications, the linearity of the image sensor is crucial for better processing performance. However, the simple source-follower based readout circuit in the conventional SIS introduces significant nonlinearity. This paper aims to design a low-power in-pixel buffer circuit applied in the high-linearity SIS for the smart perception applications.

The linearity of the SIS is improved by eliminating the non-ideal effects of transistors and cancelling dynamic threshold voltage that changes with the process variation, voltage and temperature. A low parasitic capacitance low leakage switch is proposed to further improve the linearity of the buffer. Moreover, an area-efficient SIS architecture with a sharing mechanism is presented to further reduce the number of in-pixel transistors.

A low parasitic capacitance low leakage switch and a gate-source voltage pre-storage method are proposed to further improve the linearity of the buffer. Nonlinear effects introduced by parasitic capacitance switching leakage, etc., have been investigated and solved by proposing low-parasitic and low-leakage switches. The linearity is improved without a power-hungry operational amplifier-based calibration circuit and a noticeable power consumption increment.

The proposed design is implemented using a standard 0.18-µm CMOS process with the active area of 102 µm². At the power consumption of 5.6 µW, the measured linearity is −63 dB, which is nearly 27 dB better than conventional active pixel sensor (APS) implementation. The proposed low-power buffer circuit increase not only the performance of the SIS but also the lifetime of the smart perception system.

With more and more individuals relying on mobile devices to obtain information, many libraries launch mobile application to satisfy mobile users’ information need. The purpose of this paper is to figure out factors influencing consumers’ channel transfer intention of library service from web-based platform to mobile app.

A structural equation model is proposed based on categorization theory. In addition, situational contexts are taken into account to make research model more suitable for the real condition. Data collected from 319 samples are used for hypotheses examining.

The relationships between source and target (perceived differentiation including function differentiation and resource differentiation) positively affect perceived situation efficiency, which in turn shapes intention to use mobile library application. Perceived mobile library quality positively influences perceived differentiation, perceived situation efficiency and mobile library adoption intention. In summary, perceived situation efficiency is the main factor.

Both quality and situational factors should be taken seriously, and mobile device producers and mobile app developers should cooperate on improving the quality of mobile app. Meanwhile, it is critical to examine the relationship between web based and mobile library service in the initial or early stage of mobile library development.

By focussing on the impacts of the relationship between web and mobile library service and evaluation of mobile library on the adoption intention, this paper not only provides a theoretical understanding of mobile library adoption behavior but also offers practical insights to library managers and app developers for promoting such a process.

Egoism as a moral philosophy of market economy in Adam Smith’s system is rational not ultra. It benefits not only other people but also the society led by an invisible hand. The Chinese traditional culture dominated by Confucianism, which denied gain‐seeking actuated by human selfish motives, as a whole, may be incompatible with the development of a market economy. Without rational egoism, the market economy would not exist. Meanwhile, ultra‐egoism which benefits oneself at the expense of others has also deformed the market economy. If it runs wild, the market economy would take the road to its doom.

Outlines the international travels of Clement Allan Tisdell in the period 1965‐1996 and an Australian journey made to Adelaide in 1962 for academic reasons and indicates the influence of these journeys on his publications, outlook and intellectual evolution. Emphasises how varied the life of an economist can be and the importance of international social contacts for academic development. Because of the extent of his travels, descriptions and analysis of most of his journeys are brief. Consequently, a longer story still remains untold.

The purpose of this paper is to investigate the moving boundary conditions on the sliding armature and rail (A/R) interface. As the computational domains involve both moving and stationary conductors, Lagrangian description and backward difference schemes are adopted for spatial and temporal discretization, arising discontinuities in variables. The proposed formulation can compute the current distribution under high velocities (∼km/s) without numerical oscillations and avoids mesh re-generation, saving computational resources.

The governing equations in Lagrangian description, backward difference schemes and derivations of moving boundary conditions are shown in detail. The interface matrix is explicitly enforced on the whole domain matrix and pseudocodes are presented for implementation. Moreover, shifted interpolated quantity method is proposed to deal with unevenly sized mesh, which can calculate acceleration scenarios and save computation resources under high velocities. Comparative calculations with previous methods under low velocities are conducted to verify the correctness of computational and physical models.

The current distributions with constant velocities are consistent with previous two-dimensional and low-velocity studies, further verifying the correctness of the method. The three-dimensional high-velocity results show that the current tends to concentrate near the trailing edge of A/R interface and diffuses into the bulks over time, with higher velocity contributing to less significant current diffusion. The velocity skin effect precedes the magnetic diffusion, conductivity and other factors that influence the current distribution.

The proposed methods can compute the current distributions in railgun under velocity accelerated to over 2,000 m/s, and the results provide more comprehensive understandings of the current evolution process under velocity skin effect in railgun.

As a standard source of capital for entrepreneurs, crowdfunding has recently gained wide attention in business and academia. With scientific endorsement, some research is conducted to explore the antecedents of online crowdfunding success. The factors that can influence the backers’ investment which is the key to success are information from prior backers’ and creators’ behaviors. Based on the signaling theory, the purpose of this paper is to systematically investigate the dynamic influences and interaction effects of signals with different forms (action-based or opinion-based signals) and sources (creator-sourced or backer-sourced signals) on backers’ investment behaviors over a project-funding cycle.

A panel data set of 3,010 projects with 640,625 transaction records from April 28, 2013 to September 31, 2017 is collected from a famous online crowdfunding platform – Zhongchou.cn in China and the negative binomial panel data model with fixed effect is used to obtain our empirical results.

The findings demonstrate that the work of different signals is significantly effective at the early stage of a project and decreases with time. Furthermore, our results show that there are both synergistic effect and substitution effect among different signals. Specifically, the direction of interaction effect depends on the forms of signals and the backers’ sensitivity toward that signal, and the interaction effects are also dynamic.

This paper has shed light on the roles of different signal types and their interactions in influencing funding behavior over a project-funding cycle, enriched the literature on crowdfunding and provided both theoretical and practical implications.

A kind of novel heterocyclic bisquaternary ammonium salt (MBQA) was successfully synthesised with metronidazole as matrix and dichloroethyl ether as the link agent. Weight loss measurement, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and atomic force microscopy were used to evaluate the corrosion inhibiting performance of MBQA in simulated oilfield water. Experimental data revealed that MBQA acted as an inhibitor in the acidic environment and, furthermore, the compound was a mixed‐type inhibitor. It was found that inhibition efficiency increased with an increase in MBQA concentration at different temperatures. The process of inhibition was attributed to the formation of an adsorbed film on the metal surface, which protected the metal against corrosive agents.

The purpose of this paper is to study the effects of surface roughness on the lubrication performances of the linear rolling guide, which provides theoretical guidance for its lubrication design.

The two-variable Weierstrass–Mandelbrot function is used to represent the random and multi-scale characteristics of the rough surface topography. The elastohydrodynamic lubrication (EHL) model of contact between the steel ball and raceway is built. The full numerical solutions of the pressure and film thickness are obtained by using the multi-grid technique.

The presence of surface roughness can cause the random fluctuations of the pressure and film thickness, and the fluctuations can become more dramatic for the rougher surfaces. It is also found that the film characteristics can be influenced significantly by the working conditions, such as the load, velocity and ambient viscosity of lubricants.

Characterization of surface topographies regarding EHL problems in the past studies cannot reflect random and multi-scale characteristics. In this paper, the fractal-based method is introduced to analysis of the point-contact micro-EHL. It reveals the mechanism and law of contact lubrication influenced by the fractal surface roughness and enriches the lubrication principle and method of the linear rolling guide.

As the social media platform becomes an ever more important communication channel between company and customer, companies are learning how they can best utilize social media to better communicate their brands with customers. The purpose of this paper is to explore the communication tactics adopted by the enterprise microblogs using a communication framework. Further, the authors hope to find out how these communication tactics influence customer brand experience (BE) and subsequently brand loyalty.

First, to identify the communication tactics used by enterprise microblogs, the authors recruited six active microblog users and listed all possible characteristics of enterprise microblogs that could increase customers’ fondness for the brand. Second, based on the listed 19 characteristics and existing theories, the authors pre-classified and conceptualized the content and style tactics categories. The authors also followed a sorting procedure to verify our classification. Finally, based on the sorted characteristics and previous research, the authors designed a questionnaire and 459 sets of valid data were collected from enterprise microblog users.

The communication tactics are classified into two dimensions, namely content tactics and style tactics. The content tactics include content diversity, content accuracy and content timeliness, and the style tactics include impression enhancement style and interactivity enhancement style. The results reveal that the communication content and style tactics significantly enhance overall customer BE and further brand loyalty. The study results also show that style tactics exert more influence on BE than content tactics.

This paper highlights the company’s important role in company-customer communication on social media, and categorizes the effective communication tactics used by the enterprise microblog within a communication framework. Companies could build brand loyalty by enhancing users’ BE using effective communication. The communication perspective and measures of the communication tactics in this study provide an ideal background for future research on IT-based company-customer interaction.

The purpose of this paper is to report a new method, the dissolution‐precipitation process, to prepare nylon‐coated metal powders for the indirect selective laser sintering (SLS) process.

The nylon‐12 coated carbon steel powders were prepared by the dissolution‐precipitation process. The powder characteristics are examined by scanning electron microscope (SEM) and laser diffraction particle size analysis. The effect of the applied laser energy density on the three‐point bend strength and dimensional accuracy of the SLS specimens are studied. The influence of nylon‐12 content on the bend strength are also investigated.

The SEM and laser diffraction particle size analysis results indicate that the steel particles are well coated by nylon‐12 resin. The bend strength of the SLS specimens increases with increasing the applied energy density until it reaches a maximum value, and then further increasing energy density will cause the decrease in the bend strength. The bend strength of the SLS specimens increases with increasing the nylon‐12 content over the investigated range. The dimensional errors in the X‐Y‐and Z‐directions are all increased with the increase in energy density.

This paper only concerns the preparation and SLS of the coated powders. Further investigations are planned into post‐processing, such as binder decomposition and high‐temperature sintering, of the green parts made from the coated powders.

This paper provides a useful method for preparing nylon‐coated metal powders for making metal parts by the indirect SLS process.