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The purpose of this paper is to present a novel and effective fabricating method of 3D ceramic photonic crystals with diamond structure.

The reverse diamond‐structure resin molds are fabricated by stereolithography (SL), then ceramic slurry is prepared and injected into the molds under vacuum condition. Subsequently, ceramic photonic crystals are obtained after vacuum freeze‐drying and sintering.

The combination of SL, gel‐casting and freeze‐drying could be used to fabricate the 3D ceramic photonic crystals with diamond structure which have intact structure and minimal shrinkage. The samples have been tested and the experimental results indicate that their band gap is in the range of 10.14‐12.20 GHz, consistent with the simulation results.

The influence of fabrication process on the photonic band gap needs further study.

This paper presents a novel fabricating method of 3D diamond‐structure ceramic photonic crystals based on SL, gel‐casting and freeze‐drying. The method fabricates complex ceramic photonic crystals with high accuracy and helps further research in this field.

This paper aims to examine the relationships between the group affiliates’ dual legitimacy (membership legitimacy and societal legitimacy) and dual resource acquisition (intra-group and out-group), and the moderating roles of environmental uncertainty and munificence in the emerging economies.

This paper adopts hierarchical regression analysis to test the hypotheses based on the unique data of 251 group affiliated firms in China and applies the alternative measurements and alternative methodology of structural equation modeling into robustness check to confirm the results.

The results show as follows: the group affiliates can benefit from membership legitimacy for intra-group resource acquisition and out-group resource acquisition through the mediations of societal legitimacy and intra-group resource acquisition. However, in the linkage between affiliates’ membership legitimacy and intra-group resource acquisition and the linkage between societal legitimacy and out-group resource acquisition, environmental uncertainty plays the positive moderating roles while environmental munificence plays the negative moderating roles. Under the condition of high environmental uncertainty and low environmental munificence, the linkage between membership legitimacy and intra-group resource acquisition, and the linkage between societal legitimacy and out-group resource acquisition reach the strongest level.

The findings highlight the importance of dual legitimacy building for group affiliates to acquire resources both inside and outside the business group when they operate in emerging economies characterized by high environmental uncertainty and low environmental munificence. However, it does not explore the contextual factors (e.g. institutional distance) affecting the relationship between the affiliate’s membership legitimacy and societal legitimacy. Then more group-level factors are expected to be included and explored with multi-level models in the future studies.

The findings reveal the mechanism of how group affiliates benefiting differently from dual legitimacy to acquire resources in the emerging economies, which also provide a new interpretation for the questions of who benefiting more from the group affiliation, how and why (Carney et al., 2009). This research also explores the moderating roles of task environmental characteristics (environmental uncertainty and environmental munificence) on the affiliate's dual legitimacy and dual resource acquisition, which helps understand why legitimacy building is more important in terms of resource acquisition in the emerging economy characterized by uncertainty and non-munificence.

Continuous fiber reinforced thermoplastic composites (CFRTPCs) are becoming more significant in industrial applications but are limited by the high cost of molds, the manufacturing boundedness of complex constructions and the inability of special fiber alignment. The purpose of this paper is to put forward a novel three-dimensional (3D) printing process for CFRTPCs to realize the low-cost rapid fabrication of complicated composite components.

For this purpose, the mechanism of the proposed process, which consists of the thermoplastic polymer melting, the continuous fiber hot-dipping and the impregnated composites extruding, was investigated. A 3D printing equipment for CFRTPCs with a novel composite extrusion head was developed, and some composite samples have been fabricated for several mechanical tests. Moreover, the interface performance was clarified with scanning electron microscopy images.

The results showed that the flexural strength and the tensile strength of these 10 Wt.% continuous carbon fiber (CCF)/acrylonitrile-butadiene-styrene (ABS) specimens were improved to 127 and 147 MPa, respectively, far greater than the one of ABS parts and close to the one of CCF/ABS (injection molding) with the same fiber content. Moreover, these test results also exposed the very low interlaminar shear strength (only 2.81 MPa) and the inferior interface performance. These results were explained by the weak meso/micro/nano scale interfaces in the 3D printed composite parts.

The 3D printing process for CFRTPCs with its controlled capabilities for the orientation and distribution of fiber has great potential for manufacturing of load-bearing composite parts in the industrial circle.

There is an increasing popularity for the continuum robot in minimally invasive surgery owing to its compliance and dexterity. However, the dexterity takes the challenges in loading and precise control because of the absence of the shape tracking for the continuum robot. The purpose of this paper is to propose a new type of continuum manipulator with variable stiffness that can track the bending shape timely.

The low-melting-point alloy (LMPA) is used to implement the stiffness variation and shape detection for the continuum manipulator. A conceptual design for a single module is presented, and the principle of stiffness control based on the established static model is formulated. Afterward, a shape detection method is introduced in which the shape of the continuum manipulator can be detected by measuring the resistance of every LMPA. Finally, the effect of the proposed variable stiffness method is verified by simulation; the variable stiffness and shape detection methods are evaluated by experiments.

The results from the simulations and experiments indicate that the designed continuum manipulator has the ability of stiffness variation over 42.3% and the shape detection method has high precision.

Compared with conventional structures, the novel manipulator has a simpler structure and integrates the stiffness variation and shape detection capabilities with the LMPA. The proposed method is promising, and it can be conveniently extended to other continuum manipulators.

One aspect of agency theory suggests that dominant shareholders use the firm’s assets for their personal benefits and 1thus expropriate minority shareholders (tunneling). Accordingly, this paper aims to examine the effect of capital structure and cash holding decisions on minority shareholders' expropriation for short and long periods.

Data of 16 years (2000-2015) has been obtained from 200 non-financial firms registered at Pakistan Stock Exchange (PSX). The study used fixed effect and autoregressive distributed lagged to obtain the results.

The results suggest that the presence of more debts in capital structure is positively associated with minority shareholders' expropriation, whereas a negative association has been found between the level of cash holding and minority shareholders expropriation. These results have been observed as significant both for the short and long run.

This study also suggests some important measures to control minority shareholders' expropriation by the dominant shareholders and thus to protect their rights.

There is a lack of literature for this severe issue in the developing countries especially Pakistan, so this study narrates the potential measures to the regulatory authority of the market to curb tunneling and to protect minority shareholders.

Artificial electromagnetic (EM) medium and devices are designed with integrated micro- and macro-structures depending on the EM transmittance performance, which is difficult to fabricate by the conventional processes. Three-dimensional (3D) printing provides a new solution for the delicate artificial EM medium. This paper aims to first review the applications of 3D printing in the fabrication of EM medium briefly, mainly focusing on photonic crystals, metamaterials and gradient index (GRIN) devices. Then, a new design and fabrication strategy is proposed for the EM medium based on the 3D printing process, which was verified by the implementation of a 3D 90o Eaton lens based on GRIN metamaterials.

A new design and manufacturing strategy driven by the physical (EM transmittance) performance is proposed to illustrate the realization procedures of EM medium based device with controllable micro- and macro-structures. Stereolithography-based 3D printing process is used to obtain the designed EM device, an GRIN Eaton lens. The EM transmittance of the Eaton lens was validated experimentally and by simulation.

A 3D 90o Eaton lens was realized based on GRIN metamaterials structure according to the proposed design and manufacturing strategy, which had the broadband (12-18 GHz) and low loss characteristic. The feasibility of 3D printing for the artificial EM medium and GRIN devices has been verified for the further real applications in the industries.

The applications of 3D printing in artificial EM medium and devices were systematically reviewed. A new design strategy driven by physical performance for the EM device was proposed and validated by the firstly 3D printed 3D Eaton lens.

The purpose of this paper is to explore and examine, in a systematic manner, possible preventive measures that commercial parties can take in order to prevent or reduce documentary letter of credit (L/C) fraud in international transactions.

In the context of international transactions, considering documentary L/C fraud as a risk, the paper searched preventive measures that different parties involved can adopt, from both business perspective and legal perspective.

The paper provides a number of specific measures which buyers, sellers, and banks in international L/C transactions can take in business to reduce L/C fraud. The option of banks providing additional services of checking further the validity or authenticity of some documents under the L/C, by charging additional prices, has reflected the needs of some business parties. However, this is proposed to be optional rather than compulsory for banks. The lawyers can also play an important role by adopting preventive legal mentality to help and provide advice to different parties in applying the preventive and proactive approach. More importantly, the author recommends that buyers or sellers maintain close cooperation with their banks and lawyers in implementing preventive and proactive measures.

The paper can be a helpful source of advice for business enterprises likely to be involved in international documentary L/C transactions.

This paper fulfils the gap of a holistic study on how to prevent international documentary letter of credit fraud.

The purpose of this paper is to study the rapid prototyping of porcelain products by using layer‐wise slurry deposition (LSD), in order to reduce the time to market of new or customized porcelain products or artworks.

The properties such as phase composition, microstructure, shrinkage, density, and mechanical strength, of laser sintered (LS) and biscuit fired (BF) samples, before and after post sintering in a furnace, were studied and compared with each other.

The laser sintered sample was comparable with the biscuit fired sample in porosity, but had just half the mechanical strength of the latter due to the layer‐wise fabrication process. The feasibility of rapid prototyping of porcelain products was validated by the successful fabrication of some porcelain samples, which showed that the relatively low mechanical strength of the laser sintered sample was still high enough for the following handling processes, such as surface glazing and glost firing.

The paper demonstrates the possibility of rapid prototyping of porcelain components and the models produced by using LSD process.

As the US-China conflict intensifies, the United States is pursuing a ‘decoupling’ strategy to build a new world trade order, arguing that the current World Trade Organization (WTO) system does not properly regulate China's non-market economic system. The WTO provides special and differentiated treatment (S&DT) for developing countries. The United States argues that China should give up its developing country (DC) status. Sufficient research on the DC status and S&DT has not been conducted as a means of resolving the US-China conflict. Decoupling means the collapse of the global supply chain (GSC), which will bring substantial shock to the global economy and a catastrophe for China. This paper examines the re-classification of DC status and S&DT in the context of US-China conflict and seeks an approach for China to avoid decoupling and coexist with the United States. It would be an optimal way for China to revive the WTO first and to improve its economic system through negotiations under the WTO.

The purpose of this study is to investigate the effect of standard fire on the strength and microstructure properties of concrete with different strength grades.

Different strength grades of concrete used for the investigation are M20, M30, M40 and M50. An electrical bogie hearth furnace was developed to simulate the International Standards Organization 834 standard fire curve.Concrete samples were subjected to high temperatures of 925, 1,029, 1,090 and 1,133°C for the duration of 1, 2, 3 and 4 h, respectively, as per standard fire curve. Compressive strength, tensile strength, thermal crack pattern and spalling of heated concrete specimens were evaluated by experimental investigation. Scanning electron microscopy and thermo-gravimetric analysis were performed to investigate the microstructure properties of heated concrete specimens.

Test results indicated reduction in the strength and changes in the microstructure properties of concrete exposed to elevated temperature. The degree of weight and the strength loss were found to be higher for concrete with higher grades. An empirical relation is proposed to determine the residual strength of concrete with different strength grade using regression analysis.

Results of this research will be useful for the design engineers to understand the behavior of concrete exposed to elevated temperature as per standard fire.

When concrete is exposed to elevated temperature, its internal microstructure changes, thereby strength and durability of concrete deteriorates. The performance of concrete with different strength grade exposed to standard fire is well understood. This research’s findings will be useful for the designers to understand more about fire resistance of concrete. A simple relationship is proposed to determine the residual strength of concrete exposed to various durations of heating.