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Virtual product design has become a key technology in reducing costly design errors that are often difficult to detect manually. In order to evaluate product assembly in a virtual environment, it is important to link a product's design in CAD with the constrained complexity of assembly operations in CAM so that the design can be evaluated and modified in a virtual environment before production begins. The paper aims to focus on this.

The proposed virtual system includes the following components: a product assembly coding model, named Open Structured Assembly Coding System (OSACS), that codes part‐mating operations for assembling any two parts in CAM; a rule‐based code extractor that identifies OSACS codes for assembling product from the part‐mating information encoded in Standard for the Exchange of Product Model Data AP‐203 CAD data; and an assembly‐sequence generator that generates a binary assembly‐tree for the designed product coded with OSACS assembly codes, representing assembly operations in CAM for product assembly.

The proposed system links the design phase in CAD with the manufacturing phase in CAM. Simulation studies were made using CAD Ap‐203 data files from an actual mobile phone housing assembly. A binary assembly‐tree assigned with OSACS assembly codes was generated for assembling the product. The assembling complexity between any two parts was coded with the unique OSACS assembly codes. The final binary assembly tree represents how the product is going to be assembled in CAM with the mating complexity encoded in the assigned OSACS codes.

The advantage of this virtual product assembly system is that a design can be validated first in a virtual environment without building the expensive physical production system. Moreover, additional design iterations can be performed in the same amount of time to improve product quality.

Linking product design in CAD with assembly operations in CAM can help realize significant cost savings by preventing future manufacturing problems. With the proposed virtual system, a company can prevent a potential problematic design from reaching production.

This paper introduces the conceptual design of a virtual system that links product design in CAD with assembly operations in CAM. This system provides a designer with a virtual product assembly process to evaluate a designed product.

This paper aims to study the lubrication mechanism of textured journal bearings.

CFD models for textured journal bearings are established. The effect of texture coverage on the pressure distribution is studied to find the proper texture distribution. To enhance the local load-carrying capacity at textures, the micro-hydrodynamic pressure and microflow at different texture depth ratios are captured. The interaction between the texture-induced microflow and the bearing lubrication film is analyzed from the microflow perspective.

The bearing performance is on the one hand enhanced by the micro-hydrodynamic pressure generated by textures. On the other hand, the main bearing land and maximum pressure can be interfered by textures, leading to the reduction of load-carrying capacity. To minimize the interference effect, textures are suggested to distribute downstream of the minimum film thickness location. As the lubrication film thickness increases, the corresponding optimum texture depth ratio rises. The vortices influence the local flow rate through the lubrication film at textures and further affect the micro-hydrodynamic pressure and local load-carrying capacity. The texture depth ratio, at which vortices begin to occur, generates the maximum micro-hydrodynamic pressure.

The proper texture distribution is introduced, which is capable to generate the micro-hydrodynamic pressure without interfering with the primary load-carrying capacity of the bearing. The microflow effect is found to considerably influence the local load-carrying capacity at textures. The necessity of sub-regional optimization in textured journal bearings is pointed out. This study provides the fundamental reference for the design and optimization of textured journal bearings.

The stringent requirements for environmental protection have induced the extensive applications of water-lubricated journal bearings in marine propulsion. The nonlinear dynamic analysis of multiple grooved water-lubricated bearings (MGWJBs) has not been fully covered so far in the literature. This study aims to conduct the nonlinear dynamic analysis of the instability for MGWJBs.

An attenuation rate interpolation method is proposed for the determination of the critical instability speed. Based on a structured mesh movement algorithm, the transient hydrodynamic force model of MGWJBs is set up. Furthermore, the parameters’ analysis of nonlinear instability for MGWJBs is conducted. The minimum water film thickness, side leakage, friction torque and power loss of friction are fully analyzed.

With the increase of speed, the journal orbits come across the steady state equilibrium motion, sub-harmonic motion and limit circle motion successively. At the limit circle motion stage, the orbits are much larger than that of steady state equilibrium and sub-harmonic motion. The critical instability speed increases when the spiral angle decreases or the groove angle increases. The minimum water film thickness peak is at the rotor speed of 4,000 r/min for the MGWJB with Sa = 0°. As rotor speed increases, the side leakage decreases slightly while the friction torque and the power loss of friction increase gradually.

Present research provides a beneficial reference for the dynamic mechanism analysis and design of MGWJBs.

Phenolic epoxy vinyl ester resin (PEVER) is an advanced resin matrix, which has excellent heat resistance, electrical insulation. However, the brittleness and poor toughness of its curing product limited its application, so this paper aims to modify the PEVER with hyperbranched polyimide (HBPI), so as to enhance the toughness, heat resistance and dielectric properties of PEVER.

Hexamethylene diisocyanate trimer was used as the central reactant. Methyl tetrahydrophthalic anhydride was used as the branching unit, stannous octoate was used as the catalyst and hydroquinone was prepared as the inhibitor. Then, the hyperbranched structure of HBPI was characterized by Fourier transform infrared spectrometer and ¹³C-NMR. Next, PEVER was mixed with different contents of HBPI, and then the authors tested its curing product.

It is found that with the addition of HBPI, the free volume of the system was increased and the content of polar groups was decreased in each unit space, so the dielectric constant (ε) and the dielectric loss (tanδ) were decreased. In addition, PEVER could be well toughened by HBPI and the thermal stability of PEVER was improved.

HBPI has excellent heat resistance. The addition of hyperbranched polymer increases the free volume of the system so it can slow down the transfer of stress and its nearly circular structure can absorb the impact energy from all directions. Moreover, an appropriate amount of free volume can decrease the dielectric constant of PEVER by reducing the content of polar groups.

The purpose of this paper is to introduce a weighted average method to process speed measurements from multiple magnetic sensors, which are installed on road segments. Speeds are weighted‐averaged in a fix duration time (5 minutes) for each sensor across location index of the sensor where it was installed. The proposed method is evaluated with numeric and simulation results.

Unlike traditional vehicle average speed measurements, the authors propose a weighted‐average speed measurement method of road segment, using wireless magnetic sensor nodes, which are installed on the measured road segment. Magnetic sensors offer a non‐contact vehicle detection method, and small sensors with relatively low power consumption. Using magnetic sensors, the local changes in the Earth's magnetic field caused by the presence of a moving vehicle can be measured and the vehicle's speed obtained. Next, using adaptive weighted average algorithm and space weighted algorithm in a fixed period, the weighted average travel speed of road segment can be obtained.

In current literature, there are many methods to measure vehicles' speed on road, such as image‐based, radar‐based, GPS‐based, double‐loop‐based or magnetic sensor‐based, but most of them only provide individual vehicle speed. Using probe vehicles, mean travel speed of road segment can be obtained, but it is costly on hardware and measurement, because many probe‐vehicles need to be used on roads and many measurements need to be done everyday. GPS data can be used to provide valuable travel speed data for Intelligent Transportation System (ITS). However, not every vehicle is equipped with GPS and to access ID numbers for personal cars would entail privacy problems. Mean travel speed of road segment is obtained based on statistical average speed. Generally, statistical average speed is used, which is based upon Gaussian distribution is not true in traffic systems.

By using wireless magnetic sensor nodes, vehicle instantaneous speeds are obtained in a fixed time when vehicles are passing over sensor nodes and then the adaptive weighted average speed on each sensor node location is computed based on the monitoring data from each sensor node in the fixed time. Considering different weights of each lane and road space (in the middle of the road segment or near the intersection), the proposed scheme can obtain the weighted‐average speed of the road segment.

The purpose of the present study is to examine the relationships among knowledge management strategies, innovation, and organisational performance in the Iraqi mobile telecommunication sector.

Research suggests that knowledge management strategies are essential capabilities for effective innovation and organisational performance. Through analysis of surveys collected from 220 mid‐level managers, the present study empirically tested a proposed theoretical framework by estimating structural equation model.

The results show that knowledge management strategies had a statistically significant and direct positive effect on innovation and organisational performance. Most outstandingly, the results indicate that knowledge management strategies had a positive and statistically significant effect on organisational performance through the partial mediation effect of innovation.

Conclusions of the present study may help academics and managers in implementing knowledge management strategies in order to enhance innovation and improve organisational performance.

Empirical studies show substantial variation across immigrants in the rate and direction of assimilation along various dimensions (e.g., cross-ethnic contact, language, identity). To explain this variation, past research has focused on identifying exogenous factors, such as discrimination, human capital, and settlement intention. In this chapter we argue that variation in immigrant outcomes emerges endogenously through positive interaction effects between dimensions of assimilation. We propose a new assimilation model in which processes of social influence and selection into congruent social environments give rise to multiple long-term equilibria. In this model, migrants who are already assimilated along many dimensions tend to also adapt along other dimensions, while less assimilated migrants become more strongly embedded in their ethnic group.

To test the assimilation model, we derive a number of hypotheses, which we evaluate using trend analysis and dynamic panel regression on data from the Longitudinal Survey of Immigrants to Canada.

The data mostly confirm the hypotheses, providing overall support for the assimilation model.

Our theory and findings suggest that immigrants would follow divergent assimilation trajectories even in the absence of a priori population heterogeneity in external factors.

The positive interaction effects between cultural and structural dimensions of assimilation suggest that mixed policies that promote integration while seeking to prevent loss of identity go against the natural tendency for cultural and structural assimilation to go hand in hand.

The present chapter proposes a novel model of immigrant assimilation and an empirical test.

The purpose of this paper is to provide the extensive review on dynamic monitoring of forestry area in China.

Countermeasure and suggestions were proposed for three aspects including the establishment of data sets with unified standards, top-level design of monitoring and assessment and analysis models, and establishment of the decision support platform with multiple scenario simulation.

Finally, the authors proposed key research area in this field, i.e., improving the systematic and optimal forest management through integrating and improving the data, models and simulation platforms and coupling the data integration system, assessment system and decision support system.

The authors explored the limitation of dynamic monitoring and state of the art research on data accumulation, professional model development and the analytical platform.

A significant number of Chinese companies are listed overseas. The authors aim to examine whether overseas locations affect their financing decision, specifically their capital structure choice.

Most of the Chinese overseas listed companies are listed in the USA and Hong Kong. As the institutional quality of the USA is better than Hong Kong, the authors, therefore, choose to build the hypotheses from the “law and finance” literature. Specifically, the authors argue that the better institutional environment of the USA can mitigate the information asymmetry problem and the agency problem of financing via equity. Consequently, firms listed in the USA will rely more on equity and have lower leverage ratio. The difference in leverage ratio of US listed and Hong Kong listed companies should be larger when the marginal benefit of better information environment is larger.

Referring to various data sources, the authors construct a comprehensive list of overseas listed companies in the USA and Hong Kong. The authors collect the accounting and stock performance information from Datastream/Worldscope and the equity offering data from Global New Issue database. The empirical findings provide strong support of the hypotheses: the leverage is 15 percent lower for US listed companies than the Hong Kong listed companies; the results are stronger when the firms face more severe information asymmetry problem; the stock price reacts less negatively for seasoned equity offering in the USA than in Hong Kong.

Most of the Chinese companies decided to be listed overseas because they cannot be listed in the Mainland Chinese stock exchanges. One of the most important motivation is to access to external capital to support firm growth. As the main channel of external financing in the overseas markets is equity since debt is still mainly domestically based, one implication of this paper is that Chinese companies can gain better access to external capital in the USA than in Hong Kong and relax their financial constraint.

There are a considerable number of Chinese companies listed in the overseas markets. Many successful and famous companies are among them. However, almost no research has been done based on them. This paper documents some very important phenomenon of this market. The authors wish that more studies will be conducted. In addition, the study also complements the existing studies on how institutional environment affects corporate financial behavior.