Nailong Liu, Xiaodong Zhou, Zhaoming Liu, Hongwei Wang and Long Cui
This paper aims to enable the robot to obtain human-like compliant manipulation skills for the peg-in-hole (PiH) assembly task by learning from demonstration.
Abstract
Purpose
This paper aims to enable the robot to obtain human-like compliant manipulation skills for the peg-in-hole (PiH) assembly task by learning from demonstration.
Design/methodology/approach
A modified dynamic movement primitives (DMPs) model with a novel hybrid force/position feedback in Cartesian space for the robotic PiH problem is proposed by learning from demonstration. To ensure a compliant interaction during the PiH insertion process, a Cartesian impedance control approach is used to track the trajectory generated by the modified DMPs.
Findings
The modified DMPs allow the robot to imitate the trajectory of demonstration efficiently and to generate a smoother trajectory. By taking advantage of force feedback, the robot shows compliant behavior and could adjust its pose actively to avoid a jam. This feedback mechanism significantly improves the dynamic performance of the interactive process. Both the simulation and the PiH experimental results show the feasibility and effectiveness of the proposed model.
Originality/value
The trajectory and the compliant manipulation skill of the human operator can be learned simultaneously by the new model. This method adopted a modified DMPs model in Cartesian space to generate a trajectory with a lower speed at the beginning of the motion, which can reduce the magnitude of the contact force.
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In this chapter, the author compares two representations of the child from two famous films by the Fifth Generation’s top director in China, Chen Kaige, Yellow Earth (1984) and…
Abstract
In this chapter, the author compares two representations of the child from two famous films by the Fifth Generation’s top director in China, Chen Kaige, Yellow Earth (1984) and Together (2002). The girl’s story in the former and the boy’s story in the latter show respectively the dissolution of the Party/state as an extended family home, and it being replaced by the atomized, fluid, and flexible family home in the new state-led neo-liberal order. Compared with the girl, the boy in the new century tries to convey an equally lyrical articulation of the family/home, but differently, with a strong sense of his subjectivity. Thus, the boy’s voice in Together, self-reflective, artistically innovative, and affective, becomes a voice of resistance against authoritarian neoliberalism in post-socialist China.
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Juan David Gonzalez-Ruiz, Alejandro Arboleda, Sergio Botero and Javier Rojo
The purpose of this paper is to develop an investment valuation model using the mezzanine debt mechanism based on blue bonds that explicitly allude to public–private partnerships…
Abstract
Purpose
The purpose of this paper is to develop an investment valuation model using the mezzanine debt mechanism based on blue bonds that explicitly allude to public–private partnerships (P3s) and project finance (PF). Additionally, this study proposes the financial captured value (FCV) theory for measuring how much financial value lenders may capture by becoming sponsors through financing of sustainable infrastructure systems (SIS).
Design/methodology/approach
The investment valuation model was validated through the Aguas Claras wastewater treatment plant as a case study.
Findings
The empirical results show that lenders may capture financial value by converting outstanding debt into equity shares throughout the operation and maintenance stage. Furthermore, case study results provide new insights into the implications of the debt–equity conversion ratio on the relationship between the sponsors’ internal rate of return and the FCV.
Research limitations/implications
The most significant limitation is the lack of primary and secondary information on blue bonds. Thus, robust statistical analyses to contrast results were not possible.
Practical implications
Researchers and practising professionals can improve their understanding of how mezzanine debt, P3s and PF into an investment valuation model allows financing SIS using a non-conventional financial mechanism. The recommendations will benefit both the academia as well infrastructure industry in bridging the gap between design theory and practice.
Originality/value
Sustainability components have not been addressed explicitly or combined in the financing’s structuring. Therefore, the investment valuation model could be considered a novel methodology for decision making related to financing and investment of SIS.
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Jinan Shao, Li Yin, Jing Dai and Wuyue Shangguan
As a crucial supply chain financing instrument, trade credit has become increasingly important for firms to enhance financial flows in supply chains. Yet, scant research has…
Abstract
Purpose
As a crucial supply chain financing instrument, trade credit has become increasingly important for firms to enhance financial flows in supply chains. Yet, scant research has examined how firms’ green innovation affects the attainment of trade credit from their suppliers. To bridge this gap, this study aims to draw on signalling theory to investigate the impacts of incremental green innovation (IGI) and radical green innovation (RGI) on trade credit and the contingent roles of supplier concentration and industry dynamism.
Design/methodology/approach
Using a data set of 3,302 Chinese listed manufacturing companies from 2007 to 2021, our research adopts fixed-effect regression models to test the proposed hypotheses.
Findings
The authors find that both IGI and RGI exert a positive effect on trade credit. Interestingly, supplier concentration weakens the association between RGI and trade credit, whereas it does not significantly influence the association between IGI and trade credit. Moreover, industry dynamism attenuates the relationship between IGI and trade credit, whereas it does not significantly alter the relationship between RGI and trade credit.
Originality/value
The paper extends the supply chain finance literature by applying signalling theory to uncover the effects of IGI and RGI on trade credit and the distinct contingency roles of supplier concentration and industry dynamism. It also provides supply chain managers with important implications regarding how to tailor the strategies of implementing different types of green innovation to acquire more trade credit in different situations.
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Daicong Da, Xiangyang Cui, Kai Long, Yong Cai and Guangyao Li
The optimal material microstructures in pure material design are no longer efficient or optimal when accounting macroscopic structure performance with specific boundary…
Abstract
Purpose
The optimal material microstructures in pure material design are no longer efficient or optimal when accounting macroscopic structure performance with specific boundary conditions. Therefore, it is important to provide a novel multiscale topology optimization framework to tailor the topology of structure and the material to achieve specific applications. In comparison with porous materials, composites consisting of two or more phase materials are more attractive and advantageous from the perspective of engineering application. This paper aims to provide a novel concurrent topological design of structures and microscopic materials for thermal conductivity involving multi-material topology optimization (material distribution) at the lower scale.
Design/methodology/approach
In this work, the effective thermal conductivity properties of microscopic three or more phase materials are obtained via homogenization theory, which serves as a bridge of the macrostructure and the periodic material microstructures. The optimization problem, including the topological design of macrostructures and inverse homogenization of microscopic materials, are solved by bi-directional evolutionary structure optimization method.
Findings
As a result, the presented framework shows high stability during the optimization process and requires little iterations for convergence. A number of interesting and valid macrostructures and material microstructures are obtained in terms of optimal thermal conductive path, which verify the effectiveness of the proposed mutliscale topology optimization method. Numerical examples adequately consider effects of initial guesses of the representative unit cell and of the volume constraints of adopted base materials at the microscopic scale on the final design. The resultant structures at both the scales with clear and distinctive boundary between different phases, making the manufacturing straightforward.
Originality/value
This paper presents a novel multiscale concurrent topology optimization method for structures and the underlying multi-phase materials for thermal conductivity. The authors have carried out the concurrent multi-phase topology optimization for both 2D and 3D cases, which makes this work distinguished from existing references. In addition, some interesting and efficient multi-phase material microstructures and macrostructures have been obtained in terms of optimal thermal conductive path.
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Daicong Da, Xiangyang Cui, Kai Long, Guanxin Huang and Guangyao Li
In pure material design, the previous research has indicated that lots of optimization factors such as used algorithm and parameters have influence on the optimal solution. In…
Abstract
Purpose
In pure material design, the previous research has indicated that lots of optimization factors such as used algorithm and parameters have influence on the optimal solution. In other words, there are multiple local minima for the topological design of materials for extreme properties. Therefore, the purpose of this study is to attempt different or more concise algorithms to find much wider possible solutions to material design. As for the design of material microstructures for macro-structural performance, the previous studies test algorithms on 2D porous or composite materials only, it should be demonstrated for 3D problems to reveal numerical and computational performance of the used algorithm.
Design/methodology/approach
The presented paper is an attempt to use the strain energy method and the bi-directional evolutionary structural optimization (BESO) algorithm to tailor material microstructures so as to find the optimal topology with the selected objective functions. The adoption of the strain energy-based approach instead of the homogenization method significantly simplifies the numerical implementation. The BESO approach is well suited to the optimal design of porous materials, and the generated topology structures are described clearly which makes manufacturing easy.
Findings
As a result, the presented method shows high stability during the optimization process and requires little iterations for convergence. A number of interesting and valid material microstructures are obtained which verify the effectiveness of the proposed optimization algorithm. The numerical examples adequately consider effects of initial guesses of the representative unit cell (RUC) and of the volume constraints of solid materials on the final design. The presented paper also reveals that the optimized microstructure obtained from pure material design is not the optimal solution any more when considering the specific macro-structural performance. The optimal result depends on various effects such as the initial guess of RUC and the size dimension of the macrostructure itself.
Originality/value
This paper presents a new topology optimization method for the optimal design of 2D and 3D porous materials for extreme elastic properties and macro-structural performance. Unlike previous studies, the presented paper tests the proposed optimization algorithm for not only 2D porous material design but also 3D topology optimization to reveal numerical and computational performance of the used algorithm. In addition, some new and interesting material microstructural topologies have been obtained to provide wider possible solutions to the material design.
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Laura Michelini, Cecilia Grieco and Nikolay Dentchev
The purpose of the paper is to explore how collaborations can increase the impact of food sharing platforms, which offer the potential to reduce food waste by facilitating contact…
Abstract
Purpose
The purpose of the paper is to explore how collaborations can increase the impact of food sharing platforms, which offer the potential to reduce food waste by facilitating contact between suppliers and consumers. With this comes the need to address the twofold challenge of being digital and having an economic and social-environmental mission. Thus, adopting a system perspective and recognizing stakeholders as part of a value network can maximize the generated impact.
Design/methodology/approach
A multiple case study analysis has been conducted on 12 food sharing platforms. Data have been collected through semi-structured interviews, triangulated with internal and external documents and content analysed.
Findings
The research outlines the systems of collaboration found in food sharing platforms characterized by two levels of actors (platform players and business players) and five different types of collaboration that can help platforms maximize their impact (boosting the network effect; capturing value; enhancing the business model; extending the type of impact; and scaling up).
Originality/value
The research offers important contributions for the advancement of the field, adding evidence on the opportunities offered by collaborations to generate impact for business and society in the context of the sharing economy and food industry. The research allows to identify the concept of “sustainability-oriented sharing platforms” as a subset of sharing economy platforms characterized by a dual mission and related challenges. From a managerial point of view, the study highlights how designing and implementing collaborations with the stakeholders can increase platforms' impact consistently with the life cycle and short- and long-term perspectives.
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Thomas Vogl and Grzegorz Micek
The study was designed to investigate the bidirectional causation between the real estate market characteristics (residential property prices/rents (including PTR), office rents…
Abstract
Purpose
The study was designed to investigate the bidirectional causation between the real estate market characteristics (residential property prices/rents (including PTR), office rents) and the rise of coworking spaces (CSs) in the peripheral areas of Germany.
Design/methodology/approach
Based on the desk research, the authors constructed their own database of 1,201 CSs. The authors gathered data on the residential and office prices and rents on a district level. To identify real market differences between districts with and without CSs, the authors applied the t-test for independent samples.
Findings
The second-highest number of CSs were found to operate in the office market peripheries. This phenomenon should be explained by a search for lower office rents, which CSs seek. Most CSs in the peripheral areas of Germany were only recently established in tourist-oriented regions in the south and north of Germany. In this paper, the authors confirmed that the strength of peripheral CSs lies in the hybridity of their operations: for the majority of CSs, running a CS is a non-core business. The authors argue that the role of CSs is rather limited in attracting real estate investors and boosting the real estate market in the peripheral areas of Germany.
Practical implications
The research shows that peripheral locations are attracting CSs to significant extent. The study shows that CSs can be part of corporate real estate or workplace strategies. As the majority of peripheral CSs are located in tourism areas, the subletting of vacant spaces could be a lucrative business model for hotels, particularly in the times of pandemics. Therefore, further research should focus on the role of tourist areas in the implementation of CSs model.
Originality/value
The focus of this study (CSs in peripheral areas) is original. Additionally, applying the real estate perspective to study the location of CSs is novel as well.
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Halo Dalshad Omar, Auwal Abdulkadir, Md. Roslan Hashim and Mohd Zamir Pakhuruddin
This paper aims to present investigation on textured polyimide (PI) substrate for enhanced light absorption in flexible black silicon (bSi).
Abstract
Purpose
This paper aims to present investigation on textured polyimide (PI) substrate for enhanced light absorption in flexible black silicon (bSi).
Design/methodology/approach
Flexible bSi with thickness of 60 µm is used in this work. To texture the PI substrate, copper-seeding technique is used. A copper (Cu) layer with a thickness of 100 nm is deposited on PI substrate by sputtering. The substrate is then annealed at 400°C in air ambient for different durations of 60, 90 and 120 min.
Findings
With 90 min of annealing, root mean square roughness as large as 130 nm, peak angle of 24° and angle distribution of up to 87° are obtained. With this texturing condition, the flexible bSi exhibits maximum potential short-circuit current density (Jmax) of 40.33 mA/cm2, or 0.45 mA/cm2 higher compared to the flexible bSi on planar PI. The improvement is attributed to enhanced light scattering at the flexible bSi/textured PI interface. The findings from this work demonstrate that the optimization of the PI texturing via Cu-seeding process leads to an enhancement in the long wavelengths light absorption and potential Jmax in the flexible bSi absorber.
Originality/value
Demonstrated enhanced light absorption and potential Jmax in flexible bSi on textured PI substrate (compared to planar PI substrate) by Cu-seeding with different annealing durations.
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Hongna Tian, Jingge Han, Meiling Sun and Xichen Lv
Toward sustainable development, radical green innovation (RGI) is necessary. Despite extensive research on the factors influencing green innovation, few studies have been…
Abstract
Purpose
Toward sustainable development, radical green innovation (RGI) is necessary. Despite extensive research on the factors influencing green innovation, few studies have been conducted on the precursors. Based on upper echelons (UE) theory, dynamic capability (DC) theory, “stimulus-organism-response” (SOR) theory, social information processing (SIP) theory and cognitive appraisal (CA) theory of emotion, the study explores how digital leadership (DL) affects RGI and investigates the mediating effects of green organizational identity (GOI) and the moderating effects of digital threat (DT) and technology for social good (TSG), as well as the multiple concurrent causalities that trigger high RGI.
Design/methodology/approach
The method of combining structural equation model (SEM) and fuzzy-set qualitative comparative analysis (fs QCA) is adopted in the study. Data from 233 questionnaires were collected at two different time points.
Findings
This study's findings indicate that the four dimensions of DL can positively influence RGI and GOI partially mediates between the four dimensions of DL and RGI. DT has a negative moderating effect between DL and GOI, while TSG is positively regulated between them, DT and TSG linkage moderates the partial mediating effect of GOI in DL and RGI. Further, fs QCA is used to analyze the causal complexity of DL dimensions and GOI to RGI and nine effective configuration paths are identified. It is found that the synergy of digital thinking ability (DTA), digital detection ability (DDA), digital social ability (DSA), digital reserve ability (DRA) and GOI is crucial to high RGI. Among them, GOI core appears the most times, indicating that GOI plays a vital role in improving enterprise RGI.
Originality/value
This study expands the literature on leadership and innovation by constructing a framework of “DL-GOI-RGI” and exploring the transmission of GOI and the boundary effect of DT and TSG. The study used fs QCA and SEM to better understand the statistical associations and the set relations between the conjunctions and conditions.