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The purpose of this paper is to present an analytical method for throughput analysis of assembly systems with complex structures during transients.

Among the existing studies on the performance evaluation of assembly systems, most focus on the system performance in steady state. Inspired by the transient analysis of serial production lines, the state transition matrix is derived considering the characteristics of merging structure in assembly systems. The system behavior during transients is described by an ergodic Markov chain, with the states being the occupancy of all buffers. The dynamic model for the throughput analysis is solved using the fixed-point theory.

This method can be used to predict and evaluate the throughput performance of assembly systems in both transient and steady state. By comparing the model calculation results with the simulation results, this method is proved to be accurate.

This proposed modeling method can depict the throughput performance of assembly systems in both transient and steady state, whereas most exiting methods can be used for only steady-state analysis. In addition, this method shows the potential for the analysis of complex structured assembly systems owing to the low computational complexity.

This study (1) assessed restaurant consumers' perceived importance of better food quality versus larger portion sizes, (2) classified restaurant consumers into different segments based on their perceived importance of seven food quality attributes (taste, texture, aroma, appearance and the use of natural, local and organic ingredients) relative to portion size and (3) compared the identified market segments.

An online survey assessed 613 USA adult participants' perceived importance of seven food quality attributes relative to portion size. A K-means cluster analysis classified participants into different segments based on their perceptions.

Five restaurant consumer segments were identified: sensory-oriented consumers, taste-oriented organic food consumers, local and natural food consumers, quantity-oriented consumers and quality-oriented consumers. In general, quality-oriented consumers were the least likely to visit fast-food restaurants, had the highest average per-meal spending and were the least likely to eat out alone. Local and natural food consumers and taste-oriented organic food consumers had higher total restaurant spending than other groups. Quantity-oriented and sensory-oriented consumers visited fast-food restaurants more often and had lower total restaurant spending and per-meal spending than other groups. Age, sex and income were significantly associated with the segmentation outcomes.

Findings suggest promising opportunities for restaurants to enhance consumer perceptions of value by prioritizing the factors that hold the greatest significance to their target customers.

This study is the first attempt to segment restaurant consumers based on their perceived importance of food quality attributes relative to portion size, effectively identifying five distinct consumer segments.

The purpose of this paper is to improve the generation efficiency of singlet oxygen of methylene blue molecules through finely controlling their aggregation states in drug carriers.

As a photosensitiser in photodynamic therapy, methylene blue (MB) was loaded on citrate-modified hydroxyapatite (HAp) through an electrostatic interaction and followed by encapsulation of coordination complexes of tannic acid (TA) and Fe(III) ions. Ultraviolet-visible absorption spectrum of the supernatant after incubation of samples was recorded at certain time interval to investigate the release behaviour of MB. Photodynamic activity of MB was determined by the oxidation reaction of uric acid by singlet oxygen generated by MB under illumination.

Almost all MB molecules were immediately released from HAp-MB, whilst an initial burst release of MB from HAp-MB@TA was followed by a sustainable and pH-sensitised release. In comparison with HAp-MB, photocatalystic reduction of HAp-MB@TA by titanium dioxide hardly occurred under illumination, indicating the stability against reduction to leukomethylene blue in vitro. Generation efficiency of singlet oxygen by MB released from HAp-MB@TA was significantly higher than that from HAp-MB because of the control of TA and Fe(III) ions complexes on molecular structures of released MB.

A facile method was herein demonstrated to optimise the generation efficiency of singlet oxygen by controlling aggregation states of PS molecules and improve PDT efficiency to damage tumour tissues.

This study aims to compare customers’ perceived importance of various post-COVID-19 recovery strategies (i.e. sanitary practices, discounts, menu modification and marketing strategies) adopted by independent full-service restaurants (casual dining versus upscale/fine dining) using the salience theory. It also assesses the associations between customers’ perceptions and their restaurant spending patterns.

An online survey was administered to assess 657 US adult participants’ restaurant spending behaviors at different stages of the COVID-19 pandemic using recall questions. Higher-spending versus lower-spending participants’ perceived importance of restaurant recovery strategies were compared in the casual dining versus upscale/fine dining contexts.

Amid the COVID-19 pandemic, sanitary practices were the most important factor in participants’ restaurant choices, and it was more important for independent casual dining restaurants than for upscale/fine dining restaurants. No significant difference was found in participants’ perceived importance of sanitary practices across different geographic regions. Higher-spending diners (HSD) perceived almost every restaurant recovery strategy as important. Lower-spending diners (LSD) only considered sanitary practices as important.

This study identified important strategies that restaurant operators and public health officials can adopt to help full-service restaurants recover from pandemic losses.

This study differs from previous consumer choice studies; in that it compared HSD with LSD regarding their perceived importance of various restaurant recovery strategies. This study also provides new insights for understanding the salience theory of choice under the impact of COVID-19.

Bumpless Cu/SiO₂ hybrid bonding, which this paper aims to, is a key technology of three-dimensional (3D) high-density integration to promote the integrated circuits industry’s continuous development, which achieves the stacks of chips vertically connected via through-silicon via. Surface-activated bonding (SAB) and thermal-compression bonding (TCB) are used, but both have some shortcomings. The SAB method is overdemanding in the bonding environment, and the TCB method requires a high temperature to remove copper oxide from surfaces, which increases the thermal budget and grossly damages the fine-pitch device.

In this review, methods to prevent and remove copper oxidation in the whole bonding process for a lower bonding temperature, such as wet treatment, plasma surface activation, nanotwinned copper and the metal passivation layer, are investigated.

The cooperative bonding method combining wet treatment and plasma activation shows outstanding technological superiority without the high cost and additional necessity of copper passivation in manufacture. Cu/SiO₂ hybrid bonding has great potential to effectively enhance the integration density in future 3D packaging for artificial intelligence, the internet of things and other high-density chips.

To achieve heterogeneous bonding at a lower temperature, the SAB method, chemical treatment and the plasma-assisted bonding method (based on TCB) are used, and surface-enhanced measurements such as nanotwinned copper and the metal passivation layer are also applied to prevent surface copper oxide.

The purpose of this paper is to analyze the micro-motion of the cylinder block.

Based on the elasto-hydrodynamic lubrication, a numerical model for the cylinder block/valve plate interface is proposed, with consideration of the elastic deformations, the pressure-viscosity effect and asperity contacts. The influence-function method is applied to calculating the actual deformations of the cylinder block and the valve plate. The asperity contact model simplified from Greenwood assumption is introduced into the numerical model. Furthermore, the relationship between the micro-motion and the operating condition, the sealing belt width is discussed, respectively.

The results show an increase in the discharge pressure causes the tilt state and the vibrating motion getting worse, which can be eased by improving the rotational speed, the sealing belt width and the ratio of external and internal sealing belt width.

The proposed research can provide a theoretical reference for the optimizing design of cylinder block/valve plate pair.

The purpose of this paper is to propose an adaptive control for a redundant robot manipulator interacting physically with the environment, especially with the existence of humans, on its body.

The redundant properties of the robot manipulator are used and a reference velocity variable is introduced to unify the operation-space tracking control and the null-space impedance control under one common framework. Neural networks are constructed to deal with unstructured and unmodeled dynamic nonlinearities. Lyapunov function is used during the course of control design and simulation studies are carried out to further illustrate the effectiveness of the proposed strategies.

Satisfying tracking performance in the operation-space and compliance behavior in the null-space of the redundant robot manipulator are ensured simultaneously.

The design procedure of redundant robot manipulators control can be greatly simplified, and the framework of multi-priority control can be transformed into a joint-space velocity tracking problem via the introducing of a reference velocity variable.

Provides an overview of accounting reform in China since 1993, illustrates the structure of the current (juridicial‐based) accounting system and lists the accounting standards being developed. Contrasts historical Chinese accounting methods with current attempts at international harmonization and identifies some remaining peculiarities, e.g. the dominance of the state, limited application of the prudence principle etc. Criticizes the lack of coherance in accounting regulation and the failure of accounting practice to comply with accounting standards and auditing requirements.

Interaction plays a significant role in robotics and it is considered in all levels of hardware and software control design. Several models have been introduced and developed for controlling robotic interaction. This study aims to address and analyze the state-of-the-art on robotic interaction control by which it is revealed that both practical and theoretical issues have to be faced when designing a controller.

In this review, a critical analysis of the control algorithms developed for robotic interaction tasks is presented. A hierarchical classification of distributed control levels from general aspects to specific control algorithms is also illustrated. Hence, two main control paradigms are discussed together with control approaches and architectures. The challenges of each control approach are discussed and the relevant solutions are presented.

This review presents an evolvement trend of interaction control theories and technologies over time. In addition, it highlights the pros and cons of each control approaches with addressing how the flaws of one control approach were compensated by emerging another control methods.

This review provides the robotic controller designers to select the right architecture and accordingly design the appropriate control algorithm for any given interactive task and with respect to the technology implemented in robotic manipulator.