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This paper presents some of the problems associated with the design and operation of airborne vapour cycle refrigeration equipment, created by the extreme environmental conditions, and indicates where applicable the manner in which the difficulties can be overcome. The design philosophy behind a small high‐speed oil‐free reciprocating compressor is described, by certain fundamental requirements which the designer of airborne cooling equipment must consider. The particular difficulties, associated with effects due to rapid variation of ambient air temperature and pressure, which are peculiar to design and operation of such equipment are then explained. Rapid changes in heat load necessitate careful selection of the type of compressor drive and capacity control, and since extremes of temperature occur during a comparatively short operating cycle, particular attention must be paid to control of condensing pressure, and to prevention of migration of the refrigerant liquid into the low side of the system. The effects of vibration and of high acceleration make it necessary to design the components in such a manner that they can withstand these extreme effects, both while operating and during off‐cycle periods. In conclusion, the author contends that a new field of application for refrigeration equipment is emerging as a result of the more stringent aircraft and missile requirements; considerable theoretical and experimental effort is being devoted to the many problems, and the hope is expressed that continued co‐operation between the Refrigeration and Aircraft Industries may contribute to the more conventional as well as to the more specialized applications of refrigeration.

One of the best methods to improve wind turbine aerodynamic performance is modification of the blade’s airfoil. The purpose of this paper is to investigate the effects of gurney flap geometry and its oscillation parameters on the pitching NACA0012 airfoil.

This numerical solution has been carried out for different cases of gurney flap mounting angles, heights, reduced frequencies and oscillation amplitudes, then the results were compared to each other. The finite volume method was used for the discretization of the governing equations, and the PISO algorithm was used to solve the equations. Also, the “SST” was adopted as the turbulence model in the simulation.

In this paper, the different parameters of gurney flap were investigated. The results showed that the best range of gurney flap height are between 1 and 3.2% of chord and the best ratio of lifting to drag coefficient is achieved in gurney flap with an angle of 90° relative to the chord direction. The dynamic stall angle of the airfoil with gurney flap decreases were compared to without gurney flap. Earlier LEV formation can be one of the main reasons for decreasing the dynamic stall angle of the airfoil with gurney flap. Increasing the reduced frequency and oscillation amplitude causes rising of maximum lift coefficient and consequently lift curve slope. Moreover, gurney flap with mounting angle has a lower hinge moment than the gurney flap without mounting angle but with the same vertical axis length. So, there is more complexity in structural design concerning the gurney flap without mounting angle.

Improving aerodynamic efficiency of airfoils is vital for obtaining more output power in VAWTs. Gurney flaps are one of the best mechanisms to increase the aerodynamic performance of the airfoil and increases the efficiency of VAWTs.

Investigating the hinge moment on the connection point of the airfoil, gurney flap and try to compare the gurney flap with and without angle.

This study examines the impact of climate legislation on green agricultural production and tests the heterogeneous impact of different types of climate legislation on agricultural green production.

In this study, the super-slacks-based measure (super-SBM) model is used to calculate agricultural green total factor productivity (AGTFP). The impact of climate legislation (including legislative acts and executive orders) on AGTFP is examined through regression analysis. The transmission mechanism of climate legislation affecting agricultural green production is further investigated.

This study shows that climate legislation has a positive long-term effect on AGTFP. It stimulates innovation in agricultural green technology but has a negative impact on resource allocation efficiency. Executive orders have a more significant effect on AGTFP than climate legislative acts. The effectiveness of climate legislation is more significant in countries with stronger legislation. Moreover, climate legislation reduces AGTFP in low-income countries while enhancing AGTFP in high-income countries. This effect is most prominent in upper-middle-income countries.

This study examines the different effects of various types of climate legislation, considering the level of economic development and the strength of the legal system on AGTFP. The findings can offer a global perspective and insights for China’s policymaking.

The purpose of this paper is to mount Gurney flaps at the trailing edges of the canards and investigate their influence on aerodynamic characteristics of a simplified canard-configuration aircraft model.

A force measurement experiment was conducted in a low-speed wind tunnel. Hence, the height and shape effects of the Gurney flaps on the canards were investigated.

Gurney flaps can increase the lift and pitching-up moment for the aircraft model tested, thereby increasing the lift when trimming the aircraft. The dominant parameter to influence aerodynamic characteristics is the height of Gurney flaps. When the flap heights are the same, the aerodynamic efficiency of the triangular Gurney flaps is higher than that of the rectangular ones. Moreover, the canard deflection efficiency will be reduced with Gurney flaps equipped, but the total aerodynamic increment is considerable.

This paper helps to solve the key technical problem of increasing take-off and landing lift coefficients, thus improving the aerodynamic performance of the canard-configuration aircraft.

This paper recommends to adopt triangular Gurney flaps with the height of 3 per cent chord length of the canard root (c) for engineering application.

This research proposes ideal interaction patterns for structural dimensions (buyer and supplier representatives involved in the interaction and buyer and supplier critical capabilities) for transport service outsourcing. The purpose of this paper is to establish whether those ideal interaction patterns are determinants of success of the interaction. In this paper, the latter is measured against the corresponding process success and outcome success.

This paper proposes a conceptual model based on the prior literature and adapted to this specific case of transport services. The proposed model is approached using the partial least squares simultaneous equation models. For this, the result of a survey to senior management at European machinery, electronics and automotive sector manufacturing plants has been used.

When companies possess the proposed ideal patterns for the structural dimensions, this brings with it positive effects on both the process success and the outcome success obtained by the outsourcing plant. Therefore, buyer-supplier relationships have been recognized to play a key role in the outcomes of this interaction and that the design and management of interfaces between companies and their logistics providers are critical.

Managers can use the present research findings to produce an appropriate interaction design that includes the representatives and capabilities required to make transport service outsourcing a success.

This paper contributes to the literature on transport research by specifically establishing ideal interaction patterns for the structural dimensions that buyer and supplier’s companies need to consider for achieving successful transport services outsourcing. Besides, the present research proposes a multidimensional measure of outcome success that combines major strategic, operational and financial outputs. Finally, this research represents the first survey-based empirical evidence on the topic, having used a sample of 93 plants belonging to many different companies in five European countries.

The purpose of this paper is to provide a structured literature review (SLR) and systematic insight into logistics outsourcing research, in order to identify gaps in knowledge, and provide future research direction in the logistics outsourcing discipline.

This paper identifies and synthesises information from academic journals and examines research designs and methods, data analysis techniques, geographic locations, industry engagements, year of publication, publishers, university and author affiliations. A collection of online databases from 1991 to 2016 were explored, using the keywords “third-party”, “logistics” and “outsourcing” in their title and/or abstract, to deliver an inclusive listing of journal articles in this discipline area. Based on this approach, a total of 263 articles were found and data were derived from a succession of variables.

There has been a significant increase and concentration by researchers over the past 25 years focussing on logistics outsourcing. A need to implement best practice has been universally identified, owing to increasing global supply chain complexity. This analysis shows that only seven literature reviews were published in the logistics outsourcing discipline. Additionally, this study revealed that 42 per cent of the work in this field was found to be survey based and this trend in research indicates the development of the structural equation modelling and multi-criterion decision-making methods. Investigations between 2010–2012 and 2015–2016 accounted for 151 of the total 263 articles published. Finally, reverse logistics is an area that requires special attention.

This paper is limited to a review of academic articles obtainable from online databases, containing the words “logistics” and “outsourcing” in the title and/or abstract. Additionally, only papers from high quality, peer-reviewed journals were evaluated. Other academic sources such as books and conference papers were not included in this study.

This review will provide an increased understanding of the existing state of current research, trends and future research directions in the logistics outsourcing discipline.

The purpose of this paper is to develop an integrated model, in order to identify and classify, key criteria, and to study their role in the selection process of third party logistics (3PLs) services providers for shippers' logistics need.

In this paper, an integrated model using interpretive structural modeling (ISM) and FMICMAC analysis has been developed to identify and classify the key selection criteria of 3PL services providers, typically identified by many researchers and practiced by the shippers for effective supply chain management. The key criteria are also modeled to find their role and mutual influence in the selection of 3PL services providers.

The key finding of this modeling helps to identify and classify the criteria, which may be further used, to identify the potential 3PL services provider. Integrated model reveals, criteria such as information technology capability; size and quality of fixed assets and quality of management as independent criteria, whereas criteria such as compatibility, long‐term relation and reputation as dependent criteria. Criterion namely flexibility in operation and delivery is found to be an autonomous criterion. The important criteria like quality of service, information sharing and trust, geographical spread and range of services, delivery performance, operational performance, financial stability, optimum cost, and surge capacity are found as the linkage criteria. Integrated model also establishes the direct and indirect relationship among various criteria, which plays a significant role in the selection process.

The research provide an integrated model using ISM and FMICMAC to identify and classify various key criteria required for the selection of 3PL services providers. The various key criteria have been grouped under four broad classification, namely, dependent criteria, independent criteria, autonomous criteria and linkage criteria based on their driving and dependence power, deduced from fuzzy reachability value. The model helps in the identification, classification and selection of key criteria along with their behavior, thus this research will help logistics managers to select right criteria for the selection of potential 3PL services providers for their logistics need.

The purpose of this paper is to analyze the rationale for choice of suppliers and the influence these decisions have on the firm’s capabilities.

The authors examine the choice of in-house operations vs buying maintenance in the Swedish mining industry through a qualitative case study approach.

The findings reveal a strong tendency to outsource maintenance.

This in turn has a strong influence on the firm’s capabilities and long-term competitive advantage and sustainability.

Based on the empirical findings, the authors comment on the strength and weaknesses of the different outsourcing and attempt to find practical solutions that assist the firm in creating competitive advantage.

The unique contribution of this study is that it extends prior firm capabilities studies by investigating the impact of capability loss specifically in complex, intricate maintenance processes in a dynamic industry.

When deploying a frigate to the Gulf of Aden as a part of the Operation Atalanta, the Norwegian Defence outsourced logistics to a TPL provider. The purpose of this paper is to explore the cooperation between the Defence and the TPL provider during the operation.

A qualitative design was chosen. Semi‐structured interviews were combined with relevant secondary sources. A theoretical framework formed the basis for the interviews.

No long‐term history existed between the parties before the cooperation, and no psychological contracts between individuals at tactical levels were made beforehand. Yet the cooperation was a success. It seems that this to a large degree depended on the individuals assigned to the project.

The research highlights the need to address not only how to design physical supply structures but also how to ensure adequate levels of collaborative competence within civil‐military project groups. Further research is needed to investigate how to embed key suppliers in Defence logistics structures and how supply chains for short‐term, limited deployments impact on logistics arrangements for the permanent structure of the Defence.

This research gives the Norwegian Defence valuable knowledge about how to collaborate with commercial logistics providers.

This research highlights challenges when embedding suppliers into military supply chains. This is of importance not just when supplying deployed forces but also when considering supplier integration, e.g. through PPP and PBL.

Nowadays flaps and winglets are one of the main mechanisms to increase airfoil efficiency. This study aims to investigate the power performance of vertical axis wind turbines (VAWT) that are equipped with diverse gurney flaps. This study could play a crucial role in the design of the VAWT in the future.

In this paper, the two-dimensional computational fluid dynamics simulation is used. The second-order finite volume method is used for the discretization of the governing equations.

The results show that the gurney flap enhances the power coefficient at the low range of tip speed ratio (TSR). When an angled and standard gurney flap case has the same aerodynamic performance, an angled gurney flap case has a lower hinge moment on the junction of airfoil and gurney flap which shows the structural excellence of this case. In all gurney flap cases, the power coefficient increases by an average of 20% at the TSR range of 0.6 to 1.8. The gurney flap cases do not perform well at the high TSR range and the results show a lower amount of power coefficient compare to the clean airfoil.

The angled gurney flap which has the structural advantage and is deployed to the pressure side of the airfoil improves the efficiency of VAWT at the low and medium range of TSR. This study recommends using a controllable gurney flap which could be deployed at a certain amount of TSR.