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Complexity is the main challenge for present and future manufacturers. Assembly complexity heavily affects a product’s final quality in the fully automated assembly system. This paper aims to propose a new method to assess the complexity of modern automated assembly system at the assembly design stage with respect to the characteristics of both manufacturing system and each single component to be mounted. Aiming at validating the predictive model, a regression model is additionally presented to estimate the statistic relationship between the real assembly defect rate and predicted complexity of the fully automated assembly system.

The research herein extends the S. N. Samy and H. A. ElMaraghy’s model and seeks to redefine the predictive model using fuzzy evaluation against a fully automated assembly process at the assembly design stages. As the evaluation based on the deterministic scale with accurate crisp number can hardly reflect the uncertainty of the judgement, fuzzy linguistic variables are used to measure the interaction among influence factors. A dependency matrix is proposed to estimate the assembly complexity with respect to the interactions between mechanic design, electric design and process factors and main functions of assembly system. Furthermore, a complexity attributes matrix of single part is presented, to map the relationship between all individual parts to be mounted and three major factors mentioned in the dependency matrix.

The new proposed model presents a formal quantification to predict assembly complexity. It clarifies that how the attributes of assembly system and product components complicate the assembly process and in turn influence the manufacturing performance. A center bolt valve in the camshaft of continue variable valve timing is used to demonstrate the application of the developed methodology in this study.

This paper presents a developed method, which can be used to improve the design solution of assembly concept and optimize the process flow with the least complexity.

The purpose of this paper is to describe a novel design method to construct lattice structure computational models composed of a set of unit cells including simple cubic, body-centered cubic, face-centered cubic, diamond cubic and octet cubic unit cell.

In this paper, the authors introduce a new implicit design algorithm based on the computation of volumetric distance field (VDF). All the geometric components including lattice core structure and outer skin are represented with VDFs in a given design domain. This enables computationally efficient design of a computational model for an arbitrarily complex lattice structure. In addition, the authors propose a hybrid method based on the VDF and parametric solid models to construct a conformal lattice structure, which is oriented in accordance with the geometric form of the exterior surface. This method enables the authors to design highly complex lattice structure, computational models, in a consistent design framework irrespective of the complexity in geometric representations without sacrificing accuracy and efficiency.

Experimental results are shown for a variety of geometries to validate the proposed design method along with illustrative several lattice structure prototypes built by additive manufacturing techniques.

This method enables the authors to design highly complex lattice structure, computational models, in a consistent design framework irrespective of the complexity in geometric representations without sacrificing accuracy and efficiency.

Since the Land Revolution of 1949, China has continuously practiced collective ownership of land resources and local governance at the village and township levels. This chapter argues that based on Chinese experiences, a socialist transformation is largely dependent on socialization of land resources, with the majority having access to land, food, and shelter, as well as on community organization of livelihood. This is not only the legacy of land revolution but also the foundation of Chinese society, which acts as social stabilizer. China in the past 70 years has completed primitive capital accumulation and proceeded to industrial expansion and financial adjustments. Rural China has played an important role in absorbing the shocks of cyclical economic crises induced by external and domestic factors. China adopts policies of land distribution in favor of the small peasantry and promises to defend the agrarian sector – comprising three irreducible dimensions: peasants, rural society, and agriculture, together known as Sannong, as well as the current policy of rural vitalization – against the background of macroeconomic crises, particularly amid the current economic downturn and health crises, that is, United States–China trade war, the crisis of globalization, New Cold War, and the COVID-19 pandemic. The experiences of Zhoujiazhuang Commune and Puhan Rural Community will be provided as examples to show that the bedrock of maintaining socialist transformation is the resilience of small peasantry and rural communities.

Argues that the Chinese construction industry faces a daunting challenge as it slowly migrates from a planned to a market oriented economic system, particularly, with the issue of selecting the most appropriate procurement path. One of the fundamental barriers to knowledge transfer is the historically insular nature of the Chinese Government. To overcome this, a questionnaire survey was undertaken to identify the factors influencing the choice of procurement methods adopted in the Guangdong Province. Results show that quality, risk, dispute, arbitration and price certainty were the most important discriminating factors. The traditional procurement methods are regarded as the most suitable approaches for the Guangdong Province.

In an integrated circuit (IC) substrate, more fillers, including talcum powder and aluminium hydroxide, are added, which leads to much higher rigidity and hardness compared with a traditional printed circuit board. However, the micro drilling of IC substrates is harder. This paper aims to test the drilling process of IC substrates to improve the drilling process and the micro hole quality.

Substrate drilling by a micro drill with 0.11-mm diameter was used under several drilling conditions. The influence of drilling conditions on the drilling process was observed. Drilling forces, drill wear and micro hole quality were also studied.

The deformation circle around holes, hole location accuracy, bugle hole and burrs were the major defects of micro holes that were observed during the drilling of the substrate. Reducing the drilling force and drill wear was the effective way to improve hole quality.

The technology and manufacturing of IC substrates has been little investigated. Research data on drilling IC substrates is lacking. The micro hole quality directly affects the reliability of IC substrates. Thus, improving the drilling technology of IC substrates is very important.

Taking into account the factors of torque saturation and angular velocity limitation during the actual attitude maneuver of the satellite, as well as the difficulty of parameter selection in the design of attitude control algorithm, the purpose of this paper is to propose a satellite magnetic/momentum wheel attitude control technology based on pigeon-inspired optimization (PIO) cascade-saturation control law optimization.

The optimal parameters are calculated through the PIO algorithm and then the parameters are used in the cascade-saturation control law to control the actuator findings-mathematical simulation results show that the cascade-saturation control law optimization algorithm based on PIO can shorten the adjustment time and reduce the steady-state error.

Compared with traditional attitude maneuver control with given parameters, the PIO algorithm can accurately calculate the optimal parameters needed to achieve the control objective and this method has better stability and higher accuracy.

The innovative PIO algorithm is used to calculate the optimal parameters, and the cascade saturation control law is used to control the actuator. Compared with the traditional algorithm, the regulation time is shortened and the steady-state error is reduced.

This paper aims to propose an integrated framework combining the cost-reduction rationale and the institution-leveraging rationale to explain how institutional distance, both formal and informal, influences emerging multinational enterprises (EMNEs)’ foreign direct investment (FDI) location choice. This paper also explores the moderating role of EMNEs’ FDI experience and strategic intent on value chain positioning as a reflection of firm heterogeneities, on the link between institutional distance and location choice.

This paper tests the hypotheses based on a firm-level longitudinal data set of FDI by Chinese EMNEs. The unique data are manually collected from Chinese companies listed on Shenzhen and Shanghai Stock Exchanges, composed of 250 FDI entries of 122 manufacturing firms from 2006 to 2010. The conditional logit model is used to estimate the proposed main effect and moderating effect.

Cultural distance does not deter Chinese EMNEs’ entrance in general, but firms investing in low value-added manufacturing subsidiaries are more likely to choose culturally similar countries than those investing in high value-added subsidiaries such as in upstream R&D and downstream marketing. Formal institutional distance with positive direction promotes Chinese EMNEs’ entrance, and this effect is enhanced when firms have less FDI experience and have the strategic intent to invest in high value-added subsidiaries.

This paper contributes to the current literature by identifying a holistic view of the institutional influences on FDI location choice of EMNEs and revealing how firm-level heterogeneities, particularly FDI experience and strategic intent of subsidiary value chain positioning, shape the boundary conditions of the institutional effects in different ways.

In this paper, a kind of an oil groove structure which could improve the transmission torque of an oil film was designed, i.e. the width and depth of oil groove gradually decrease with the increase in the radius.

Effects of the structural parameters of the oil groove on the hydro-viscous drive (HVD) characteristics with variable rotational speed were investigated by means of numerical calculation.

Research results show that with the decrease of the width and depth of the oil groove at the outer diameter, transmission torque increases, while the temperature is almost unchanged. Keeping the effective area unchanged, comparing the transmitted torque under the oil groove angle θ₂ = 0.5° and θ₂ = 4.5°, the former was almost 200 per cent of the latter; the torque transmitted with h₂ = 0.05 mm was almost 150 per cent of that with h₂ = 0.2 mm.

In this paper, the authors analyze the friction surface of the friction plate between the oil groove, oil distribution and oil film transfer torque from the oil groove structure parameters and found methods to improve the transmission torque. For the first time, the influence of the structural parameters of oil groove on the characteristics of HVD was studied under the condition of variable rotational speed, and a better method to improve the transmission torque was proposed.

The purpose of this paper is to study the working characteristics of hydro-viscous clutch at high rotational speeds and obtain the trend of flow field variation of oil film.

The FLUENT simulation model of the oil film between the friction disks is built. The effect of variation of working parameters such as input rotational speed, oil flow rate and film thickness on two-phase flow regime and transmission torque is studied by using the volume of fluid model.

The results show that the higher the rotational speed, the severer the cavitation is. In addition, the two-phase flow region makes the coverage of oil film over the friction pairs’ surface reduce, which results in a decrease in transmission torque for the hydro-viscous clutch.

These simulation results are of interest for the study of hydro-viscous drive and its applications. This study can also provide a theoretical basis for power transmission mechanism of oil film by considering the existence of a two-phase flow regime consisting of oil and air.