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The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed, obtain better surface finish, achieve material flexibility and reduce equipment costs.

The freeform additive manufacturing approach conceptually views a 3D article as an assembly of freeform elements distributed spatially following a flexible 3D assembly structure, which conforms to the surface of the article and physically builds the article by sequentially forming the freeform elements by a vari-directional vari-dimensional capable material deposition mechanism. Vari-directional building along tangential directions of part surface gives surface smoothness. Vari-dimensional deposition maximizes material output to increase build rate wherever allowed and minimizes deposition sizes for resolution whenever needed.

Process steps based on geometric and data processing considerations were described. Dispensing and forming of basic vari-directional and vari-dimensional freeform elements and basic operations of joining them were developed using thermoplastics. Forming of 3D articles at build rates of 2-5 times the fused deposition modeling (FDM) rate was demonstrated and improvement over ten times was shown to be feasible. FDM compatible operations using 0.7 mm wire depositions from a variable exit-dispensing unit were demonstrated. Preliminary tests of a surface finishing process showed a result of 0.8-1.9 um Ra. Initial results of dispensing wax, tin alloy and steel were also shown.

This is the first time that both vari-directional and vari-dimensional material depositions are combined in a new freeform building method, which has potential impact on the FDM and other additive manufacturing methods.

Rotary disc is a key component in the compact spherical pump, connecting shaft and piston, bearing hydraulic force conformally and constituting dynamic working chambers alternatively. Motion of rotary disc comprises two components. One is rotating around its own axis and the other is sliding on a cone surface. Therefore, it is necessary to investigate the friction and wear mechanism between rotary disc and cylinder under a complicated operation condition.

Structural properties of rotary disc are analyzed first. Frictional moment of rotary disc is modeled based on its structural characteristics and working mechanism, and the constraints of the structural parameters are considered. Besides, the concept of dimensionless contact area is proposed. Comparison is performed between the proposed concept and the frictional moment to determine an optimized beginning angle for spherical pump with a given displacement. The wear model of rotary disc is also established based on its kinematic property, a velocity coefficient is proposed and its common values are presented.

Effects of structural parameters, i.e. beginning angle and ending angle on the frictional moment, are obtained quantitatively. The frictional moment increases with beginning and ending angle with different rates. While the dimensionless contact area decreases with beginning angle. The larger the piston angle, the larger the velocity coefficient will be. The rotary disc wears severely with a larger beginning angle and smaller ending angle, while it has the smallest wear rate under a smaller beginning angle and a larger ending angle.

The originality lies in modeling the complex contact force of rotary disc based on its specific structure. These conclusions can be used to optimize the structural parameters of rotary disc.

The purpose of this paper is to design and fabricate a three-dimensional (3D) bionic airflow sensing array made of two multi-electrode piezoelectric metal-core fibers (MPMFs), inspired by the structure of a cricket’s highly sensitive airflow receptor (consisting of two cerci).

A metal core was positioned at the center of an MPMF and surrounded by a hollow piezoceramic cylinder. Four thin metal films were spray-coated symmetrically on the surface of the fiber that could be used as two pairs of sensor electrodes.

In 3D space, four output signals of the two MPMFs arrays can form three “8”-shaped spheres. Similarly, the sensing signals for the same airflow are located on a spherical surface.

Two MPMF arrays are sufficient to detect the speed and direction of airflow in all three dimensions.

This study aims to investigate the electrochemical corrosion performance of high velocity oxygen fuel (HVOF) sprayed WC–12Co coating in 3.5 Wt.% NaCl solution, which provided a guiding significance on the corrosion resistance of H13 hot work mould steel.

A WC–12Co coating was fabricated on H13 hot work mould steel using a HVOF, and the electrochemical corrosion behaviors of WC–12Co coating and substrate in 3.5 Wt.% NaCl solution was measured using open circuit potential (OCP), potentiodynamic polarization curve (PPC) and electrochemical impedance spectroscopy (EIS) tests.

The OCP and PPC of WC–12Co coating positively shift than those of substrate, its corrosion tendency and corrosion rate decrease to enhance its corrosion resistance. The curvature radius of capacitance curve on the WC–12Co coating is larger than that on the substrate, and the impedance and polarization resistance of WC–12Co coating increase faster than those of substrate, which reduces the corrosion process.

The electrochemical corrosion behaviors of WC–12Co coating and substrate in 3.5 Wt.% NaCl solution is first measured using OCP, PPC and EIS tests, which improve the electrochemical corrosion resistance of H13 hot work mould steel.

Relationships are a critical success factor for business operations across markets with dominant Chinese culture, like Taiwan. The intersection of a high-quality institutional environment and a traditional Chinese cultural background in Taiwan provides a unique setting for exploring different types of relational mechanisms and ensuing renqing practices (i.e. reciprocal exchange of favors with empathy). The purpose of this paper is to examine when, where and how Taiwanese high-performance organizations manage and deploy interorganizational renqing across their business relationship portfolios. Answering these questions can help build a theory of interorganizational renqing and advance interorganizational reciprocity theorization more generally.

This research is motivated by two key research questions. First is related to how renqing givers understand renqing in the context of their organizations and their interorganizational business relationship portfolios. Second, whether organizations prefer a neutral renqing balance, a renqing debt or a renqing surplus is another point of interest. The study is based on interviews with upper echelon elite informants at six high-performing Taiwanese organizations with business relationship portfolios worldwide.

It is found that interorganizational renqing is deployed as a hybrid resource, taking on the functions of both an investment and a type of insurance against risk. Two notable differences between interorganizational and interpersonal renqing are also noted. First, the social exchange norm aspect of renqing points to salient social exchange norms also in interorganizational exchanges. This confirms the importance of understanding not only the regulative and normative dimensions of business relationships, as a type of institution, but also the cognitive dimensions and underlying institutional logics. Second, this study shows that unlike at the interpersonal level, the notion of renqing debt is not common at the interorganizational level – at least not within high-performance organizations with market leader positions.

This study explores interorganizational renqing practices and their strategic deployment through the use of “accessing” and “embedding” relational mechanisms. The study also adds to the poorly understood nature of interorganizational reciprocity and provides support for developing a theory of interorganizational renqing, as a form of interorganizational reciprocity within a Chinese cultural context.

This paper aims to develop a method to improve the accuracy of tolerance analysis considering the spatial distribution characteristics of part surface morphology (SDCPSM) and local surface deformations (LSD) of planar mating surfaces during the assembly process.

First, this paper proposes a skin modeling method considering SDCPSM based on Non-Gaussian random field. Second, based on the skin model shapes, an improved boundary element method is adopted to solve LSD of nonideal planar mating surfaces, and the progressive contact method is adopted to obtain relative positioning deviation of mating surfaces. Finally, the case study is given to verify the proposed approach.

Through the case study, the results show that different SDCPSM have different influences on tolerance analysis, and LSD have nonnegligible and different influence on tolerance analysis considering different SDCPSM. In addition, the LSD have a greater influence on translational deviation along the z-axis than rotational deviation around the x- and y-axes.

The surface morphology with different spatial distribution characteristics leads to different contact behavior of planar mating surfaces, especially when considering the LSD of mating surfaces during the assembly process, which will have further influence on tolerance analysis. To address the above problem, this paper proposes a tolerance analysis method with skin modeling considering SDCPSM and LSD of mating surfaces, which can help to improve the accuracy of tolerance analysis.

This paper aims to explore the sources of China's property boom from 2000 to 2009. The basic research hypothesis is that the property boom is largely associated with Chinese local governments’ incentive structure which prioritizes GDP growth for evaluating their performance.

Based on the fixed effects panel data regression model of 35 major Chinese cities, the determinants of property investment, property price and land sale price are identified. In particular, the roles of local governments in boosting the property boom are discussed.

Property investment is driven by accelerating urbanization process, easier availability of bank loans and more housing sales. Meanwhile, higher disposable income, more housing sales and increasing property investment are identified to mainly account for the property price escalation. It is further demonstrated that increasing property price has positive effect on land sale price. Local governments have quickened the urbanization process, released more bank loans and sold more land through public auction to support property development, sustain property price and increase land sale revenue. Such behaviour is closely related to Chinese local governments’ incentive structure.

Previous studies have not empirically tested the relationships between local governments’ pursuits for higher revenue in the urban land market and China's magnified and sustained property boom over the past decade. A prosperous property market is conducive to economic development and hence local officials’ chances of political promotion.

The purpose of this paper is to present a clear picture of the challenges of micro drill bit and the developments of novel micro‐drill bits for flexible circuit boards, environmental‐friendly printed circuit boards (PCBs), high aspect ratio drill bit and ultra‐small micro drill bit, as well as the developments of geometry design of micro drill bit.

The paper details the developments trend and challenges of micro drill and PCBs first. Then the current research status of novel micro drill bits for flexible circuit boards, environmental‐friendly PCBs, high aspect ratio drill bit, ultra‐small micro drill bit are described. Finally, the developments of geometry design and drilling process are reviewed.

To achieve excellent performance for drilling flexible PCB, a large helical angle, large flute/land ratio and small web thickness that guarantee the sharp evacuation capability, are adopted in drill bit design. A small helix angle and an appropriate primary face angle are employed for drill bit to process environmental‐friendly printed circuit boards. It is beneficial to implement big helix angle, small primary face angles and small point angles in the design of ultra‐small micro drill bit. An optimum web thickness and step feed should be taken into consideration in high aspect ratio drill bits design.

The paper reviews different solutions of micro drill bits for the state‐of‐the‐art PCB and the developments of geometry design of drill bit for printed circuit boards.

While companies in developed countries are increasingly turning to indigenous employees, integration measures have met with mixed results. Low integration can lead to breach of the psychological contract, i.e. perceived mutual obligations between employee and employer. The purpose of this paper is to identify how leadership and organizational integration measures can be implemented to promote the perceived insider status (PIS) of indigenous employees, thereby fostering fulfillment of the psychological contract.

A search for relevant literature yielded 128 texts used to identify integration measures at the level of employee–supervisor relationships (leader-member exchanges, inclusive leadership) and at the level of employee–organization relationships (perceived organizational support, pro-diversity practices).

Measures related to leadership included recruiting qualified leaders, understanding cultural particularities, integrating diverse contributions and welcoming questions and challenges. Organizational measures included reaching a critical mass of indigenous employees, promoting equity and participation, developing skills, assigning meaningful tasks, maintaining good work relationships, facilitating work-life balance, providing employment security, fostering support from communities and monitoring practices.

While PIS has been studied in western and culturally diverse contexts, it has received less attention in indigenous contexts. Yet, some indigenous cultural values are incompatible with the basic assumptions of mainstream theories. Furthermore, colonial policies and capitalist development have severely impacted traditional indigenous economic systems. Consequently, indigenous people are facing many barriers to employment in ways that often differ from the experiences of other minority groups.

China's real estate market is rampantly expanding. The purpose of this paper is to examine the factors underpinning China's real estate price escalation from 1998 to 2009.

Cointegration approach, vector error correction model and Granger causality test are adopted to analyze whether stable and long‐run equilibrium interactions exist between housing prices and key macroeconomic variables, such as CPI, land sale and GDP.

Cointegration analysis shows long‐term equilibrium between real estate price (HP) and CPI or GDP, but not land sale. A bilateral Granger causality is observed between CPI and HP. However, GDP does not Granger cause HP, indicating personal gain (disposable income) does not catch up with national gain (GDP) in China, or “Guojinmintui” (national gain outpaces personal gain). Neither is there a feedback effect from HP to GDP, indicating housing price appreciation does not result in immediate capital gain or speculations in housing purchase. Besides, lack of cointegration relationships between HP and land sale is probably caused by restrictive polices on land supply.

This paper represents the first attempt to adopt cointegration approach and Granger causality tests to examine the real estate price escalation in China using national monthly data. Econometric analysis and subsequent policy discussion suggest that real estate price is driven by both economic and institutional factors. In particular, “Guojinmintui” is a fiscal issue while capital gain is a monetary issue. Together with land market policies, these institutional factors significantly contribute to the price escalation.