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Article
Publication date: 4 January 2021

Huichao Wang, Qin Lian, Dichen Li, Chenghong Li, Tingze Zhao and Jin Liang

Reconstructing multi-layer tissue structure using cell printing to repairing complex tissue defect is a challenging task, especially using in situ bioprinting. This study…

Abstract

Purpose

Reconstructing multi-layer tissue structure using cell printing to repairing complex tissue defect is a challenging task, especially using in situ bioprinting. This study aims to propose a method of in situ bioprinting multi-tissue layering and path planning for complex skin and soft tissue defects.

Design/methodology/approach

The scanned three-dimensional (3D) point cloud of the skin and soft tissue defect is taken as the input data, the depth value of the defect is then calculated using a two-step grid division method, and the tissue layer is judged according to the depth value. Then, the surface layering and path planning in the normal direction are performed for different tissue layers to achieve precise tissue layering filling of complex skin soft tissue defects.

Findings

The two-step grid method can accurately calculate the depth of skin and soft tissue defects and judge the tissue layer accordingly. In the in situ bioprinting experiment of the defect model, the defect can be completely closed. The defect can be reconstructed in situ, and the reconstructed structure is basically the same as the original skin tissue structure, proving the feasibility of the proposed method.

Originality/value

This study proposes an in situ bioprinting multi-tissue layering and path planning method for complex skin and soft tissue defects, which can directly convert the scanned 3D point cloud into a multi-tissue in situ bioprinting path. The printed result has a similar structure to that of the original skin tissue, which can make cells or growth factors act on the corresponding tissue layer targets.

Details

Rapid Prototyping Journal, vol. 27 no. 2
Type: Research Article
ISSN: 1355-2546

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Book part
Publication date: 16 December 2016

Tobias Polzer, Renate E. Meyer, Markus A. Höllerer and Johann Seiwald

Despite an abundance of studies on hybridization and hybrid forms of organizing, scholarly work has failed to distinguish consistently between specific types of hybridity…

Abstract

Despite an abundance of studies on hybridization and hybrid forms of organizing, scholarly work has failed to distinguish consistently between specific types of hybridity. As a consequence, the analytical category has become blurred and lacks conceptual clarity. Our paper discusses hybridity as the simultaneous appearance of institutional logics in organizational contexts, and differentiates the parallel co-existence of logics from transitional combinations (eventually leading to the replacement of a logic) and more robust combinations in the form of layering and blending. While blending refers to hybridity as an “amalgamate” with original components that are no longer discernible, the notion of layering conceptualizes hybridity in a way that the various elements, or clusters thereof, are added on top of, or alongside, each other, similar to sediment layers in geology. We illustrate and substantiate such conceptual differentiation with an empirical study of the dynamics of public sector reform. In more detail, we examine the parliamentary discourse around two major reforms of the Austrian Federal Budget Law in 1986 and in 2007/2009 in order to trace administrative (reform) paradigms. Each of the three identified paradigms manifests a specific field-level logic with implications for the state and its administration: bureaucracy in Weberian-style Public Administration, market-capitalism in New Public Management, and democracy in New Public Governance. We find no indication of a parallel co-existence or transitional combination of logics, but hybridity in the form of robust combinations. We explore how new ideas fundamentally build on – and are made resonant with – the central bureaucratic logic in a way that suggests layering rather than blending. The conceptual findings presented in our paper have implications for the literature on institutional analysis and institutional hybridity.

Details

How Institutions Matter!
Type: Book
ISBN: 978-1-78635-431-0

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Article
Publication date: 4 August 2020

Mehmet Caner Akay and Hakan Temeltaş

Heterogeneous teams consisting of unmanned ground vehicles and unmanned aerial vehicles are being used for different types of missions such as surveillance, tracking and…

Abstract

Purpose

Heterogeneous teams consisting of unmanned ground vehicles and unmanned aerial vehicles are being used for different types of missions such as surveillance, tracking and exploration. Exploration missions with heterogeneous robot teams (HeRTs) should acquire a common map for understanding the surroundings better. The purpose of this paper is to provide a unique approach with cooperative use of agents that provides a well-detailed observation over the environment where challenging details and complex structures are involved. Also, this method is suitable for real-time applications and autonomous path planning for exploration.

Design/methodology/approach

Lidar odometry and mapping and various similarity metrics such as Shannon entropy, Kullback–Leibler divergence, Jeffrey divergence, K divergence, Topsoe divergence, Jensen–Shannon divergence and Jensen divergence are used to construct a common height map of the environment. Furthermore, the authors presented the layering method that provides more accuracy and a better understanding of the common map.

Findings

In summary, with the experiments, the authors observed features located beneath the trees or the roofed top areas and above them without any need for global positioning system signal. Additionally, a more effective common map that enables planning trajectories for both vehicles is obtained with the determined similarity metric and the layering method.

Originality/value

In this study, the authors present a unique solution that implements various entropy-based similarity metrics with the aim of constructing common maps of the environment with HeRTs. To create common maps, Shannon entropy–based similarity metrics can be used, as it is the only one that holds the chain rule of conditional probability precisely. Seven distinct similarity metrics are compared, and the most effective one is chosen for getting a more comprehensive and valid common map. Moreover, different from all the studies in literature, the layering method is used to compute the similarities of each local map obtained by a HeRT. This method also provides the accuracy of the merged common map, as robots’ sight of view prevents the same observations of the environment in features such as a roofed area or trees. This novel approach can also be used in global positioning system-denied and closed environments. The results are verified with experiments.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 6
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 1 January 2012

Angela Samantha Maitland Irwin, Kim‐Kwang Raymond Choo and Lin Liu

The purpose of this paper is to measure the size of the money laundering and terrorism financing problem, identify threats and trends, the techniques employed and the…

Abstract

Purpose

The purpose of this paper is to measure the size of the money laundering and terrorism financing problem, identify threats and trends, the techniques employed and the amount of funds involved to determine whether the information obtained about money laundering and terrorism financing in real‐world environments can be transferred to virtual environments such as Second Life and World of Warcraft.

Design/methodology/approach

Analysis of 184 Typologies obtained from a number of anti‐money laundering and counter‐terrorism financing (AML/CTF) bodies to: determine whether trends and/or patterns can be identified in the different phases of money laundering or terrorism financing, namely, the placement, layering and integration phases; and to establish whether trends and/or behaviours are ubiquitous to a particular money laundering or terrorism financing Type.

Findings

Money launderers and terrorism financers appeared to have slightly different preferences for the placement, layering and integration techniques. The more techniques that are used, the more cash can be successfully laundered or concealed. Although terrorism financers use similar channels to money launderers, they do not utilise as many of the placement, layering and integration techniques. Rather, they prefer to use a few techniques which maintain high levels of anonymity and appear innocuous. The sums of monies involved in money laundering and terrorism financing vary significantly. For example, the average maximum sum involved in money laundering cases was AUD 68.5M, as compared to AUD 4.8 for terrorism financing cases.

Originality/value

This paper provides some insight into the relationship between predicate offence, the predominant techniques utilised in carrying out that offence and the sums of money involved.

Details

Journal of Money Laundering Control, vol. 15 no. 1
Type: Research Article
ISSN: 1368-5201

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Article
Publication date: 29 February 2008

Salvador Parrado

This paper aims to show that the Spanish central administration, as a representative of the Napoleonic tradition, has undergone considerable managerial changes in…

Abstract

Purpose

This paper aims to show that the Spanish central administration, as a representative of the Napoleonic tradition, has undergone considerable managerial changes in non‐autonomous and semi‐autonomous agencies characterised by their direct involvement in service delivery in spite of the failure of macro‐changes and radical reforms of public administration.

Design/methodology/approach

This paper provides case studies of “paths” of changes in three organisations.

Findings

Through “layering” and “diffusion” of institutions as social mechanisms included in the historical new institutionalism account for innovation, specific organisations like the tax agency, social security and property registry have become more managerial in a state dominated by public law.

Research limitations/implications

More in‐depth case studies would make possible generalisation of how small changes can produce similar impacts or results than reform efforts at the macro‐level.

Originality/value

The use of historical neo‐institutionalism and the exam of mechanisms as “layering” and “diffusion” for explaining change is presented.

Details

International Journal of Public Sector Management, vol. 21 no. 2
Type: Research Article
ISSN: 0951-3558

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Book part
Publication date: 14 January 2021

Iryna Kushnir

This chapter draws together the findings about both the Bologna actors and instruments to explain the mechanism of the Bologna reform in Ukraine until 2014 and its place…

Abstract

This chapter draws together the findings about both the Bologna actors and instruments to explain the mechanism of the Bologna reform in Ukraine until 2014 and its place in Europeanisation in the post-Soviet context.

This research demonstrates that continuity was mainly perpetuated by the Ministry of Education and Science, and change was facilitated by civil organisations. There was a lot of fluidity in the interaction of old practices and policy innovation in Bologna in Ukraine. The interaction between the path dependency and change was primarily a gradual chaotic, yet creative, and shared build-up of minor innovations by different higher education actors. These innovations in the development of the Bologna instruments may be seen as leading to more substantial transformations over time.

The research findings may also serve as a first step towards a reconceptualisation of the Europeanisation process particularly in the post-Soviet context in the first couple of decades after the collapse of the Soviet Union. Bologna in Ukraine can be seen as an illustration of the ways in which Europeanisation may not always necessitate the elimination of past conventions and practices – indeed, in a policy field such as education, abandoning history and tradition would have been a futile endeavour. Policy continuity in the post-Soviet context may be a foundation in the Europeanisation process during which minor innovations are slowly yet continuously being accumulated. This foundation shapes the nature of changes. Therefore, perhaps, the debate regarding a slow pace of Europeanisation in the post-Soviet space might be erroneous, since it carries a hidden assumption – that it is slow in relation to a much faster Europeanisation and resulting transformations in the EU. Such a comparison should be revisited in light of a potential difference in the nature of Europeanisation in the two spaces and the acknowledgement of growing overlaps between the two spaces as well.

Details

The Bologna Reform in Ukraine
Type: Book
ISBN: 978-1-83982-114-1

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Article
Publication date: 1 December 2004

James Brink, Alex Lee, David Anderson and Karthik Ramani

This paper describes algorithms and software for decomposing CAD models for a new mold manufacturing process called WirePATH™, which uses wire electrical discharge…

Abstract

This paper describes algorithms and software for decomposing CAD models for a new mold manufacturing process called WirePATH™, which uses wire electrical discharge machining (EDM) to reduce mold fabrication time. A decomposition strategy has been developed to account for the limitations of wire EDM. During decomposition, CAD models are separated into manufacturable segments and then layered if they contain curved or relatively flat sloped surfaces because wire EDM is limited to steeply sloped ruled surfaces. A new algorithm for direct adaptive layering of CAD models is developed. The algorithm analyzes surface error by comparing line segments against actual curves from the model surface. Also, the maximum angle needed to produce each layer is checked, and, in some cases, the layers are reconstructed to conform to the maximum angle.

Details

Rapid Prototyping Journal, vol. 10 no. 5
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 29 November 2018

Joseph R. Kubalak, Alfred L. Wicks and Christopher B. Williams

Material extrusion (ME) suffers from anisotropic mechanical properties that stem from the three degree of freedom (DoF) toolpaths used for deposition. The formation of…

Abstract

Purpose

Material extrusion (ME) suffers from anisotropic mechanical properties that stem from the three degree of freedom (DoF) toolpaths used for deposition. The formation of each layer is restricted to the XY-plane, which produces poorly bonded layer interfaces along the build direction. Multi-axis ME affords the opportunity to change the layering and deposition directions locally throughout a part, which could improve a part’s overall mechanical performance. The purpose of this paper is to evaluate the effects of changing the layering and deposition directions on the tensile mechanical properties of parts printed via multi-axis ME.

Design/methodology/approach

A multi-axis toolpath generation algorithm is presented and implemented on a 6-DoF robotic arm ME system to fabricate tensile specimens at different global orientations. Specifically, acrylonitrile butadiene styrene (ABS) tensile specimens are printed at various inclination angles using the multi-axis technique; the resulting tensile strengths of the multi-axis specimens are compared to similarly oriented specimens printed using a traditional 3-DoF method.

Findings

The multi-axis specimens had similar performances regardless of orientation and were equivalent to the 3-DoF specimens printed in the XYZ orientation (i.e. flat on the bed with roads aligned to the loading condition). This similarity is attributed to those sets of specimens having the same degree of road alignment.

Practical implications

Parts with out-of-plane loads currently require design compromises (e.g. additional material in critical areas). Multi-axis deposition strategies could enable local changes in layering and deposition directions to more optimally orient roads in critical areas of the part.

Originality/value

Though multi-axis ME systems have been demonstrated in literature, no prior work has been done to determine the effects of the deposition angle on the resulting mechanical properties. This work demonstrates that identical mechanical properties can be obtained irrespective of the build direction through multi-axis deposition. For ABS, the yield tensile strength of vertically oriented tensile bars was improved by 153 per cent using multi-axis deposition as compared to geometrically similar samples fabricated via 3-DoF deposition.

Details

Rapid Prototyping Journal, vol. 25 no. 2
Type: Research Article
ISSN: 1355-2546

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Book part
Publication date: 14 January 2021

Iryna Kushnir

This chapter reviews the theoretical literature about Europeanisation and argues the need for further analysis of post-Soviet Europeanisation. This chapter also connects…

Abstract

This chapter reviews the theoretical literature about Europeanisation and argues the need for further analysis of post-Soviet Europeanisation. This chapter also connects post-Soviet Europeanisation to the notion of policy learning, which is introduced as a theoretical perspective. The chapter discusses the challenges around the definition of policy learning in relation to other policy processes such as transfer, translation and diffusion. Policy layering does not presuppose mutual exclusion between path-dependence and change, but rather the fruitful mutual development of both. It implies a gradual change of certain policy aspects and the retaining of others. The development of the links between path-dependence and change in layering is a highly messy process. Multiple actors participate in learning, and they create policy as they learn. There are no distinct stages of learning, and the line between policy-makers and practitioners is often blurred.

The difference between policy-making on the European level and the post-Soviet domestic context is significant. The literature about post-Soviet countries recognises the presence of a struggle between Europeanisation and post-Soviet legacies there. Europeanisation in this literature is presented as change; while the influence of the post-Soviet legacies is seen as an obstacle that hinders it. The policy learning concept is key here to frame Europeanisation in the post-Soviet context as an area of enquiry which may develop according to the logic of layering.

Details

The Bologna Reform in Ukraine
Type: Book
ISBN: 978-1-83982-114-1

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Book part
Publication date: 7 August 2019

Jacob Reilley and Tobias Scheytt

This study sets out to shed light on those infrastructures underlying the ubiquitous, yet contested nature of governing by numbers. Investigating the 30-year long…

Abstract

This study sets out to shed light on those infrastructures underlying the ubiquitous, yet contested nature of governing by numbers. Investigating the 30-year long emergence of Germany’s “external quality assurance system” for hospitals, the authors show how methods for quantifying quality align with broader institutional and ideational shifts to form a calculative infrastructure for governance. Our study focuses on three phases of infrastructural development wherein methods for calculating quality, institutions for coordinating data and reform ideals converge with one another. The authors argue that the succession of these phases represents a gradual layering process, whereby old ways of enacting quality governance are not replaced, but augmented by new sets of calculative practices, institutions and ideas. Thinking about infrastructures as multi-layered complexes allows us to explore how they construct possibilities for control, remain stable over time and transform the fields in which they are embedded. Rather than governance being enacted according to a singular goal or value, we see an infrastructure that is flexible enough to support multiple modalities of control, including selective intervention, quality-based competition and automatized budgeting. Infrastructural change, instead of revolving around crises in measurement, is shaped by incubation periods – times of relative calm when political actors, medical practitioners, mathematicians, and many others explore and reflect past experiences, rather than follow erratic reforms fads. Finally, analysing infrastructures as multi-layered constructs underlines how they produce multiple images of care quality, which not only shift existing power relations, but also change the ways we understand and make sense of public services.

Details

Thinking Infrastructures
Type: Book
ISBN: 978-1-78769-558-0

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