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The purpose of this paper is to propose a robotic system for percutaneous surgery. The key component in the system, a robotic arm that can manipulate a puncture needle is presented. The mechanical design, the motion control and the force control method of the robotic arm are discussed in the paper.

The arm with an arc mechanism placed on a 3D Cartesian stage is developed as a puncture needle manipulator to locate the position of the needle tip, tune the needle’s posture and actuate the puncture motion under the visual guidance of two orthogonal X-ray images of a patient by a surgeon. A focusing method by using two laser spots is proposed to automatically move the needle tip to a surgery entry point on the skin. A dynamics model is developed to control the position of the needle mechanism and an explicit force control strategy is utilized to perform the needle insertion.

With the surgical system, a surgeon can easily perform puncture operation by taking two orthogonal real-time X-ray images as a visual feedback and accurately navigating the needle insertion. The laser-guided focusing method is efficient in placement of the needle tip. The explicit force control strategy is proved to be effective for holding constant and stable puncture force in experiments.

The robotic arm has an advantage in easy redirection of the needle because the rotation and the translation are decoupled in the mechanism. By adopting simple laser pens and a well-developed kinematics model, the system can handle the entry point, locating task automatically. The focusing method and the force control method proposed in the paper are useful for the present system and could be intuitive for similar surgical robots.

This paper aims to address the following issues: (1) most existing methods are based on recurrent network, which is time-consuming to train long sequences due to not allowing for full parallelism; (2) personalized preference generally are not considered reasonably; (3) existing methods rarely systematically studied how to efficiently utilize various auxiliary information (e.g. user ID and time stamp) in trajectory data and the spatiotemporal relations among nonconsecutive locations.

The authors propose a novel self-attention network–based model named SanMove to predict the next location via capturing the long- and short-term mobility patterns of users. Specifically, SanMove uses a self-attention module to capture each user's long-term preference, which can represent her personalized location preference. Meanwhile, the authors use a spatial-temporal guided noninvasive self-attention (STNOVA) module to exploit auxiliary information in the trajectory data to learn the user's short-term preference.

The authors evaluate SanMove on two real-world datasets. The experimental results demonstrate that SanMove is not only faster than the state-of-the-art recurrent neural network (RNN) based predict model but also outperforms the baselines for next location prediction.

The authors propose a self-attention-based sequential model named SanMove to predict the user's trajectory, which comprised long-term and short-term preference learning modules. SanMove allows full parallel processing of trajectories to improve processing efficiency. They propose an STNOVA module to capture the sequential transitions of current trajectories. Moreover, the self-attention module is used to process historical trajectory sequences in order to capture the personalized location preference of each user. The authors conduct extensive experiments on two check-in datasets. The experimental results demonstrate that the model has a fast training speed and excellent performance compared with the existing RNN-based methods for next location prediction.

This paper aims to investigate and prepare the composite polyurea greases with excellent thermal stability and tribological properties.

In this paper, composite Ba-based (Ba, barium) tetra-polyurea lubricating greases were prepared with two different methods: mixing Ba-based gelatinizer and tetra-polyurea gelatinizer by a physical method; and introducing barium carboxylate into tetra-polyurea molecules by a chemical method. The properties of the products, such as heat stability, water resistance and friction performance, were analyzed with thermogravimetry, water-resistance test and four-ball friction test.

The results indicated that the products obtained by chemically introducing barium carboxylate into tetra-urea molecules showed better elevated temperature tribological properties, and the disadvantages of the polyurea greases with high temperature hardening were also obviously improved. The cone penetration rate at 180°C for 24 h is only 3 per cent. The friction coefficient can be decreased to 0.44 and the last non-seizure load value was increased from 560 N to 1,120 N without any other additives.

The research is significant because the prepared composite grease showed excellent performances, such as the outstanding thermal stability, water resistance and excellent extreme pressure and anti-wear properties, which may be widely applied in steel, metallurgy, bearings and other industrial fields.

The purpose of this paper is to develop and test a dynamic model of security-based consumer purchasing intentions and empirically addresses gaps in online purchasing theory by examining how loyalty intention may become stronger or weaker over time as a result of prior relationship evaluations.

Using a longitudinal study (three-time waves) of commercial website consumers, the authors investigate the proposed model by depicting the relationships among perceived security, perceived risk, website trust and loyalty intentions.

The results show that two relationships, namely the perceived security-perceived risk link and the perceived risk-website trust link, which have been little investigated on a longitudinal basis in previous studies, change over time. Interestingly, while social network service (SNS) information perceptions do not have direct effects on perceived risk or loyalty intention, the relationships in which either perceived security and website trust are involved are more important for positively improving perceived security and building website trust.

The authors suggest that managers may actually benefit from handling SNS information or social communities by delivering well-designed information at strategic stages, targeting key constructs.

The research contributes to the establishment and testing of temporal carryover effects of various online purchasing-related constructs: perceived security, perceived risk, trust and loyalty intention. More specifically, the longitudinal approach provides new insights regarding the role, potential impact and limitations of two types of perception. It thus highlights how understanding loyalty intention requires reevaluating consumer perceptions as consumers’ judgments evolve.

The primary objective of this study is characterizing the anisotropic mechanical properties of corrugated cardboard and simultaneously simulating its drop cushioning dynamic effects under various drop conditions.

Static and dynamic tests were conducted on corrugated cardboard to obtain adequate experimental data in different directions. An effective anisotropic constitutive model is introduced by developing the honeycomb materials model in ANSYS LS-Dyna, and an effective approach is established toward effectively determining the material parameters from the test data obtained. The model is validated by comparing simulation results with experimental data from five drop conditions, including bottom drop, front drop, side drop, 30° side drop and edge drop. Additionally, simulations are conducted to study the cushioning performance of the packaging by dropping the corrugated cardboard at different heights.

The study establishes a fast and effective approach to simulating the drop cushioning performance of corrugated cardboard under various drop conditions, which demonstrates good agreement with experimental data.

This approach is of value for packaging protection and provides guidance for stacking of packaging during transportation.

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.

This study examines the influence of Centrality of Visual Product Aesthetics (CVPA) on multi-stage food consumption and emotions under aesthetic disruption, assessing how CVPA affects consumption and whether food aesthetics moderate these behaviours and emotional responses.

Data were collected using qualitative interviews and quantitative experimental designs, employing a moderated mediation model for statistical analysis.

Consumers with higher CVPA are more likely to adopt multi-stage consumption for higher aesthetic food, generating greater positive emotions, both in personal experiences and when viewing food bloggers' posts.

This study introduces the novel concept of “multi-stage consumption” and investigates its origins and outcomes.

On the basis of principal-agent and financing constraints theories, the purpose of this paper is to construct a unified research framework via mathematical models and to provide a logical and consistent explanation of the contradictory discovery of the relationship between dividend payment and I-CFO in the previous literature.

Establishing the economic mathematical models, this paper uses the comparative static analysis to figure out the equilibrium results, to further testify the conclusions, the authors initiate the empirical tests to make the discussion more realistic.

The authors observe that overinvestment caused by agency problems is the primary reason for I-C sensitivity when the investment expenditure is less than the internal capital; dividend payout suppresses the overinvestment caused by the agency problem, thus alleviating the investment’s dependence on the internal capital. However, underinvestment caused by the financing constraints is the primary cause of I-C sensitivity when the investment expenditure is greater than the internal capital. The payment of cash dividends increases the investment shortage caused by the financing constraints, thus increasing the sensitivity. Further, the authors explore the impact of dividend payments on I-CFO sensitivity. They argue that dividend payment is not an appropriate measure of financing constraints. Both I-CFO sensitivity and I-C sensitivity are functions of agency cost and information cost.

This study provides a logical and consistent explanation of the contradictory discovery of the relationship between dividend payment and I-CFO in the previous literature and provides a clear framework and reference for future studies on the impact of financial constraints, agency cost on the investment’s dependence on the internal capital.

The theoretical model of this paper supports this differentiated mandatory dividend policy and provides reference and evidence for China's financing policies and dividend distribution policies.

This study theoretically and empirically analyzes and verifies the roles of agency cost and financial constraints on the determinants of I-C sensitivity for the first time. First, different from earlier literature, this paper puts forward I-C sensitivity as a new measure of investment’s dependence on internal capital, making the measurement more accurate. In the case of a firm with positive liquidity reserves, using the I-CFO sensitivity as a measure of external financing constraints could overestimate the firm’s financial constraints. Second, by constructing an economic static analysis framework, this study analyzes how I-C and I-CFO sensitivities change with the agency cost, the financing constraints and the dividend payment ratio. The research provides a basic framework and explanation on the contradictions of the earlier literature. The results are supposed to serve as a foundation for estimations of investment’s dependence on internal capital and should be embedded in general empirical tests in future research.

This empirical study, from the international retailing perspective, examines the direction of retailers' further expansion after initial entry into overseas host market in the context of the luxury fashion retail market in China.

The research adopts qualitative multiple case studies.

After initial entry into China, luxury fashion retailers further expand their retail operations through three directional patterns: cautious, regional and countrywide expansions. The stepwise expansion from tier-1 to tier-2 and tier-3 cities remains popular; however, the importance of the tier system of Chinese cities has been weakened because tier-3 cities in affluent regions are perceived to have more potential than some tier-2 cities in less developed regions. The retailers assess a potential local market through interrelated criteria, including location and strategic importance, economic development, available store locations and staff, a high degree of urbanisation and tourism, debatable favourable policies and offers, and popularity of e- and m-commerce. There is a positive relationship between popularity of e- and m-commerce in a city and the potential of that city to run brick-and-mortar stores.

The paper offers an insight into the current international retailing literature by examining the direction of luxury fashion retailers' further expansion after their initial market entry. Particularly, the research considers a set of criteria which can be used to assess a potential local market, and the impact of e- and m-commerce on local market choices for brick-and-mortar stores.

From an international retailing perspective, this empirical study aims to examine luxury fashion retailers' changing marketing strategies in China.

Using case studies of 14 luxury fashion retailers, qualitative data were collected via 31 semi-structured executive interviews.

Both standardised global and localised multinational marketing strategies were found to have initially been employed by luxury fashion retailers entering into China. Subsequently, localised multinational strategies became increasingly important for their post-entry operations and business development, particularly in terms of their product strategies. More specifically, as well as the introduction of Chinese brand names, product design has been adapted according to Chinese market conditions, and product portfolios have been adapted to satisfy regional differences. However, localised product sourcing in China is far less common.

As the findings are generated from China, they may not explain luxury fashion retailers' marketing strategies in other markets. Despite the relatively small sample size, the 14 luxury fashion retailer case studies originate from across a wide range of countries, retail formats and ownership structures and are therefore considered to be varied enough to represent the market.

The study offers practitioners insights into the success that can be generated by the manipulation of marketing strategies, particularly product strategies, within the world's second biggest luxury market.

This paper extends the current international retailing literature by examining and comparing the motives and practices of luxury fashion retailers and the increasing localisation of their marketing strategies in China as they move from initial market entry into their post-entry operations.