S. Kumar, J.‐P. Kruth, J. Van Humbeeck and A. Voet
Surface changes like wear or local plastic deformation occurring during service of a mould make it unsuitable for further use and determine its life‐time. The performance of the…
Abstract
Purpose
Surface changes like wear or local plastic deformation occurring during service of a mould make it unsuitable for further use and determine its life‐time. The performance of the mould and its design are important aspects that influence its longevity. The purpose of this paper is to study the behaviour of mould materials manufactured by laser sintering, a type of rapid manufacturing process, and to explain their relative in‐service performance.
Design/methodology/approach
Mould specimens were made by two laser‐sintering machines (a DTM Sinterstation and an EOSint M250 Xtended equipped with CO2 lasers) using two iron‐based commercial powders, i.e. LaserForm ST‐100 and DirectSteel 20 V1, respectively. They have been subjected to two types of wear tests, i.e. bidirectional fretting and unidirectional pin‐on‐disc tests, under loading conditions leading to wear and/or plastic deformation of the specimens. The results obtained show similar trends to that obtained from the real‐life performance of polymer injection moulds manufactured using such materials and processes.
Findings
LaserForm is a better material for injection moulds material than DirectSteel; however, and its performance will deteriorate under impact injection moulding conditions where plastic surface deformation will occur in addition to abrasive wear. Both materials show high coefficient of friction, their performance will be enhanced by redesigning the composition of the powders by incorporating hard and low friction components. The methodology adopted here for investigating the surface degradation behaviours of materials is able to give sufficient and reliable information about the wear behaviour of mould materials for practical applications.
Originality/value
It is concluded that the wear tests used here are suited to characterize the in‐service mould wear strength, and such tests could be preferably used to shorten the mould development/validation time.
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Salwa H El-Sabbagh and Nivin M. Ahmed
This paper aims to express in detail the rheological, morphological and thermal properties of unpigmented and pigmented styrene-butadiene rubber composites with new prepared…
Abstract
Purpose
This paper aims to express in detail the rheological, morphological and thermal properties of unpigmented and pigmented styrene-butadiene rubber composites with new prepared inorganic pigment based on kaolin covered with a thin layer of calcium and magnesium oxides or mixed oxide of both together. These new pigments combine the properties of both their constituents (kaolin and metal oxides), which are a new trend in inorganic pigments called core-shell pigments. The pigments used for comparison are kaolin (K), CaO/kaolin (CaO/K), MgO/kaolin (MgO/K) and CaO.MgO/kaolin (CaO.MgO/K).
Design/methodology/approach
The different pigments were characterized using different analytical and spectrophotometric techniques, such as X-ray diffraction, scanning electron microscopy/energy dispersive X-ray and transmission electron microscopy, while rubber vulcanizates' rheological, morphological, swelling and thermal properties were examined using different standard and instrumental testing and methods.
Findings
The study revealed that there is a significant effect of the new prepared pigments on SBR properties, where the optimum pigment loading was 40 phr for CaO/kaolin, while it was 2.5 phr for MgO/kaolin. Studying the effect of different ratios of oxides on kaolin (5, 10 and 20 per cent), different loadings of these pigments ranging between 2.5 and 40 phr were done for each pigment. These modified kaolin or core-shell metal oxide/kaolin pigments imparted new and improved reinforcing properties to SBR vulcanizates.
Research limitations/implications
No research limitations were found.
Practical implications
Core-shell MgO/kaolin pigments are eco-friendly and can replace other expensive pigments that are usually used as fillers in the rubber industry with less expenses and comparable efficiency.
Originality/value
These new pigments are cheap and efficient and can be used in different fields other than rubber.
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Joris van der Voet, Ben Kuipers and Sandra Groeneveld
Public organizations often need to implement organizational change. Several authors have argued that the specific characteristics of public organizations make the implementation…
Abstract
Purpose
Public organizations often need to implement organizational change. Several authors have argued that the specific characteristics of public organizations make the implementation of organizational change in public organizations distinct or even more difficult. However, this issue has received little empirical investigation in both public management and change management research. Public organizations typically operate in an environment characterized by checks and balances, shared power, divergent interests and the political primate. The purpose of this paper is to advance knowledge about how the implementation of change and its leadership is affected by the complex environment in which public organizations operate.
Design/methodology/approach
A case study approach is adopted. A merger of three government departments in a Dutch city is selected as a case. This merger took place in an environment that became increasingly complex as the implementation process advanced. The main method of data collection was interviewing the managers that were involved in the organizational change. In all, 23 interviews were conducted and fully transcribed. The interviews were then coded using Atlas.ti software.
Findings
The analysis indicates that a high degree of environmental complexity forces public organizations to adopt a planned, top-down approach to change, while the effectiveness of such an approach to change is simultaneously limited by a complex environment. In addition, typical change leadership activities, such as defining the need for change, role modeling and motivating employees to implement the change, are not sufficient to implement change in a complex environment. In order to overcome environmental dependencies and maintain momentum in the change process, public managers must engage in more externally oriented leadership activities.
Originality/value
The paper provides empirical evidence about the relevant and rapidly growing research topic of organizational change in public organizations. The paper concludes with hypotheses that can be tested in follow-up research, and as such provides a starting point for future research concerning change management in public organizations.
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Ramona Palos and Vesna Veres Stancovici
This study aims at identifying the presence of the dimensions of learning capabilities and the characteristics of a learning organization within two companies in the field of…
Abstract
Purpose
This study aims at identifying the presence of the dimensions of learning capabilities and the characteristics of a learning organization within two companies in the field of services, as well as identifying the relationships between their learning capability and the organizational culture.
Design/methodology/approach
This has been a transversal study on a convenience sample of 64 employees from two companies. The questionnaires’ purpose was to identify and assess organizational learning capability, dimensions of the learning organization and the role of organizational culture.
Findings
The results showed a better represented capability of organizational learning and a more evident presence of the dimensions that characterize a learning organization within a private company. Also, the type of organization is a moderator for the relationship between the hierarchical culture and adhocracy on one hand and the dimension of experimenting organizational learning on the other hand, but also between the market culture and dialogue dimension.
Research limitations/implications
The reduced dimension and the structure of the sample or using certain self-report-type questionnaires represent some of the limits of this study.
Practical implications
The results highlight the way the type of organization and the organizational cultures influence the factors that facilitate learning. Knowing this allows the specific intervention upon those factors that can contribute to the increase of the organizational learning capabilities.
Originality/value
The study depicts the factors that make a difference on the learning and action level of the organizational culture in two different organizational realities: a public one with local top management and a private one with foreign top management.
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Stefano Borzillo and Salem Alshahrani
The purpose of this study is to uncover the essential conditions for establishing a successful collaboration between the Fairmont Hotel (Makkah) staff and the senior management…
Abstract
Purpose
The purpose of this study is to uncover the essential conditions for establishing a successful collaboration between the Fairmont Hotel (Makkah) staff and the senior management team to prepare for cocreating a future shared corporate vision.
Design/methodology/approach
This study is an action research project involving senior managers of the Fairmont Hotel (Makkah) and EHL Hospitality Business School (Lausanne, Switzerland). Data were collected from 16 hotel staff members, covering functional/department managers, team leaders, operations supervisors and operational-level employees.
Findings
This study uncovered a series of generic proposals made by the hotel staff, which are prerequisites/conditions for successful collaboration with senior management, to prepare for cocreating a future shared vision.
Practical implications
In response to the staff’s generic proposals, the senior management team proposed practical measures to support continued collaboration between hotel staff and the senior management team. These measures aim to maintain a collaborative approach centered on achieving future common goals and a shared vision to promote sustainable innovation in the services of the Fairmont Hotel (Makkah).
Originality/value
This study is innovative in two respects. First, it demonstrates a strong willingness on the part of senior management and staff to collaborate less vertically, contrary to the cultural norm in Saudi Arabia, known for its strong hierarchical distance. Second, the mutual commitment to more horizontal collaboration is not typical of five-star hotels, which are traditionally vertical and hierarchical.
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Daniel Berhin, Frédéric Godart, Maya Jollès and Paul Nihoul
This paper aims to question the disappearance of sector‐specific regulation in European electronic communications markets.
Abstract
Purpose
This paper aims to question the disappearance of sector‐specific regulation in European electronic communications markets.
Design/methodology/approach
To show that sector‐specific regulation will remain, five arguments are developed based on different disciplines: law, economics, political science and sociology.
Findings
It is found that sector‐specific regulation has already been in place for 15 years and there is no concrete indication that it will end soon. Competition law has intrinsic limitations, which, arguably, do not make it possible for authorities to resort only to that body of the law to ensure a smooth functioning of the electronic communications markets. The balance of power in the EU leads to sector‐specific regulation being maintained in the years ahead as the ideal way for European institutions to intervene in electronic communications markets. The electronic communications market requires regulation going beyond competition law in order to ensure the realization of non‐economic purposes. The implementation of sector‐specific regulation might contribute to concentrating the electronic communications markets.
Practical implications
Contrary to the claims of the European institutions that sector‐specific regulation in the electronic communication markets will lose its relevance, this paper argues that it is likely to remain for the foreseeable future.
Originality/value
The paper shows that deregulating a sector is not an easy task and that ex ante regulation is a key legal instrument for the proper functioning of a market.
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This study examines the way in which our judiciary approach the interpretation of fiscal legislation. It traces the roots of the historical approach (the strict and literal…
Abstract
This study examines the way in which our judiciary approach the interpretation of fiscal legislation. It traces the roots of the historical approach (the strict and literal approach), its shortcomings and the modifications to such an approach when it leads to an absurdity. It then analyses whether the advent of the Constitution (Constitution of the Republic of South Africa Act 108 of 1996) has been a catalyst for a change from the strict and literal approach. The conclusion reached is that the Constitution has been a catalyst for a change in approach ‐ to a purposive approach. One of the results of the change in approach means that the taxpayer now has a realistic opportunity to question and even have unjust and unfair interpretation decisions of the past reversed in the appropriate circumstances.
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S.S. Gustafsson and M. Bruyn‐Hundt
Compares the way women are taxed in the Germany, Sweden and TheNetherlands by looking at both macro and micro data from the perspectiveof a wife′s contribution to family income…
Abstract
Compares the way women are taxed in the Germany, Sweden and The Netherlands by looking at both macro and micro data from the perspective of a wife′s contribution to family income. The programs used for analysis are included in an appendix. Taxing husbands and wives by adding joint incomes and dividing by two (as in Germany) penalises dual‐earner couples and favours one‐earner couples. Completely separate taxation (as in Sweden) is a major incentive for couples to be dual‐earner. In The Netherlands the government reform of the tax system (1990) has reduced negative tax effects on secondary earnings without introducing the positive effects seen in Sweden. Tax incentives are not the only determinant of women′s participation in the labour market.
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Johannes Glasschroeder, Emanuel Prager and Michael F. Zaeh
The purpose of this paper is to show a possibility of how new functions can be integrated in parts, created by the powder-bed-based 3D-printing technology. One big advantage of…
Abstract
Purpose
The purpose of this paper is to show a possibility of how new functions can be integrated in parts, created by the powder-bed-based 3D-printing technology. One big advantage of additive manufacturing technologies is the possibility to create function-integrated parts during the manufacturing process. This applies to mechanical functions like movable elements, thermodynamic functions like contour near cooling channels in a part as well as electrical functions like conductive lines and electrical components.
Design/methodology/approach
A powder-bed-based 3D-printer is utilized to process polymethyl methacrylate (PMMA) as base material. To enable new functionalities, an automated exhausting mechanism was implemented into the test system. The created cavities can be filled with new components or rather new materials.
Findings
Three different approaches are shown in this paper. The first one was the integration of screw nuts to enhance bolted joints compared to threads, directly created in the part. The average tensile strength could be raised from 200 to 430 N/mm. The second approach was the integration of different reinforcement elements like carbon or metallic fibers. Here again a reinforcement of the tensile strength of approximately 27 per cent could be reached. The last approach shows a method to integrate conductive material as well as electrical components in a part to create simple electrical circuits.
Originality/value
The paper demonstrates how to extend an additive powder-bed-based technology with a powder-exhausting mechanism. The possibilities of this technology are illustrated by three examples, integrating mechanical as well as electrical functions in a part.
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Sabika Allehdan, Asma Basha and Reema Tayyem
Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy. GDM is defined as glucose intolerance of variable severity with onset or first…
Abstract
Purpose
Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy. GDM is defined as glucose intolerance of variable severity with onset or first recognition during pregnancy. The purpose of this paper is to produce information on prevalence, screening and diagnosis, pathophysiology and dietary, medical and lifestyle management of GDM.
Design/methodology/approach
This literature review aimed to document and record the results of the most updated studies published dealing with dietary, medical and lifestyle factors in managing GDM.
Findings
The prevalence of GDM differs worldwide based on population characteristics, race/ethnicity and diagnostic criteria. The pathophysiology of GDM is multifactorial and it is likely that genetic and environmental factors are associated with the occurrence of GDM. Medical nutritional therapy remains the mainstay of GDM management and aerobic and resistance physical activities are helpful adjunctive therapy when euglycemia is not attained by the medical nutritional therapy alone. When diet and exercise fail to achieve glycemic control, pharmacological agents such as insulin therapy and oral hypoglycemic medications are prescribed. Plasma glucose measurement is an essential part of glycemic control during pregnancy, as well as glycemic control can be evaluated using indicators of glycemic control such as hemoglobin A1c (HbA1c), glycated albumin and fructosamine.
Originality/value
This review is a comprehensive review that illustrates the effect of healthy diet, medical therapy and lifestyle change on improving GDM condition.