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The purpose of this paper is to develop a new rectilinear branch pipe‐routing algorithm for automatic generation of rectilinear branch pipe routes in constrained spaces of aero‐engines.

Rectilinear branch pipe routing that connects multiple terminals in a constrained space with obstacles can be formulated as a rectilinear Steiner minimum tree with obstacles (RSMTO) problem while meeting certain engineering rules, which has been proved to be an NP‐hard and discrete problem. This paper presents a discrete particle swarm optimization (PSO) algorithm for rectilinear branch pipe routing (DPSO‐RBPRA) problems, which adopts an attraction operator and an energy function to plan the shortest collision‐free connecting networks in a discrete graph space. Moreover, this paper integrates several existing techniques to evaluate particles for the RSMTO problem in discrete Manhattan spaces. Further, the DPSO‐RBPRA is extended to surface cases to adapt to requirements of routing pipes on the surfaces of aero‐engines.

Pipe routing numeral computations show that, DPSO‐RBPRA finds satisfactory connecting networks while considering several engineering rules, which demonstrates the effectiveness of the proposed method.

This paper applies the Steiner tree theory and develops a DPSO algorithm to plan the aero‐engine rectilinear branch pipe‐routing layouts.

The paper aims to present a modified particle swarm optimization (MPSO) approach for automatic generation of near‐optimal pipe routes in constrained aero‐engine 3D rotational space.

Pipe assembly for aero‐engine is formulated as searching for the optimal pipe paths meeting certain objectives in a constrained 3D rotational space. The routing space is first modelled by grid discretization in the cylindrical coordinate system, and then is simplified into several 2D planes by mapping development. The objective function is formulated to minimize the pipe lengths and the number of pipe turns, to place pipes next to the inner jacket as close as possible, and also to make pipe trajectories closely follow around obstacle contours while avoiding collisions. Then, an MPSO approach, which adopts a discrete operator and a fixed‐length encoding mechanism, is developed to seek optimal solutions to the objective function. The convergence of MPSO is theoretically proved. Finally, numerical computations of pipe‐routing examples are conducted by using Matrix Laboratory and Unigraphics NX 4.0 system, which demonstrates effectiveness and efficiency of the proposed method.

Results show that MPSO can quickly find the optimal pipe routes meeting certain engineering constraints, and also manifests better computation convergences.

The application of the MPSO approach in pipe routing for aero‐engines is demonstrated. MPSO is a general modified particle swarm optimization version that it is not restricted to the pipe‐routing problems, and the routing approach can also be applied in similar path‐planning problems such as robot path‐planning and very large‐scale integration design.

The paper develops a new formulation for aero‐engine pipe‐routing problems, and presents an MPSO approach to find the optimal pipe paths.

The purpose of this paper is to develop a computationally efficient and generally applicable measure for a pipe routing problem which decides the pipe paths and affects the pipe assembly feasibility. By imitating human thinking in pipe assembly planning, human's experience and intuition are quantified and applied in the pipe routing algorithm.

Human's imaginal thinking is simulated with procedures of knowledge representation, pattern recognition, and logical deduction; the algorithm transforms the physical obstacles and constraints into 3D pipe routing space and then into 2D planar projection, by using convex hull algorithm onto the projection, the shortest pipe route is found efficiently.

A novel pipe assembly planning algorithm by imitating human imaginal thinking is presented, which effectively solved the problem of conceiving the shortest pipe route in 3D space with obstacles and constraints.

The application of the algorithm in assembly planning of an aircraft engine pipe system is demonstrated. The algorithm can also be used in similar pipe planning problems such as industrial plant pipe planning and submarine pipe system design.

Human's imaginal thinking is introduced into pipe routing algorithm for the first time. By using graphics as the media to transfer the pipe routing information, human's experience and intuition in pipe assembly planning are quantified and computationally applicable.

As a kind of NP-hard combinatorial optimization problem, pipe routing design (PRD) is applied widely in modern industries. In the offshore oil and gas industry, a semi-submersible production platform is an important equipment for oil exploitation and production. PRD is one of the most key parts of the design of semi-submersible platform. This study aims to present an improved ant colony algorithm (IACO) to address PRD for the oil and gas treatment system when designing a semi-submersible production platform.

First, to simplify PRD problem, a novel mathematical model is built according to real constraints and rules. Then, IACO, which combines modified heuristic function, mutation mechanism and dynamical parameter mechanism, is introduced.

Based on a set of specific instances, experiments are carried out, and the experimental results show that the performance of IACO is better than that of two variants of ACO, especially in terms of the convergence speed and swarm diversity. Finally, IACO is used to solve PRD for the oil and gas treatment system of semi-submersible production platform. The simulation results, which include nine pipe paths, demonstrate the practicality and high-efficiency of IACO.

The main contribution of this study is the development of method for solving PRD of a semi-submersible production platform based on the novel mathematical model and the proposed IACO.

This paper aims to propose an optimization method to automatically adjust the spatial route of multibend pipes to meet the assembly demands in constrained space.

The compact geometric parameters that uniquely determine the pipe route are analyzed. Besides, the relationship between these parameters and the end pose is revealed based on the exponential product formula. Mathematical representations for the engineering constraints, including the end pose restriction, collision interference, manufacture ability and geometric limitations, are further established. On this basis, the adjustment of the spatial route is formulated as a multiconstraint optimization problem. A modified particle swarm optimization method based on the combination of gradient projection and swarm intelligence is designed to find the near-optimal pipe that meets the required assembly demands.

The experimental results show that the proposed method can effectively find the feasible pipe route that satisfies the engineering constraints and the end pose requirement is highly guaranteed.

The proposed method can automate the geometric adjustment of multi-bend pipes to meet the actual assembly demands, which significantly reduces manual efforts and guarantees high accuracy. The results demonstrate the possibility of further applications in the pipe assembly or design process, especially in ships, aerospace products or pressure vessels.

Water systems in civil aircraft, stimulated by passenger comfort needs, have grown to be a comprehensive and important part of aircraft engineering. In this article, following a review of the system types, the design features arc discussed in detail and emphasis has been placed on the functional and hygiene requirements, and on the need for simplicity and weight conservation. Attempts have been made to augment air‐borne water supplies by reclamation means, but these have not been too successful. Investigations should therefore continue into the ways and means of improving the utilization of existing ‘fixed’ capacity systems. Installation safety aspects are also discussed.

The purpose of this paper is to provide an overview of the potential use of virtual reality systems in facilities management design solutions.

The approach focuses on the human designer and acknowledges the importance of human input to the design process. The development of a metaphor‐based VR system is reported along with initial field trials, which compare VR with conventional CAD systems.

In the context of facilities management solutions advantages of using VR over CAD are shown and discussed along with strengths, weaknesses and future work.

The literature reviewed is not exhaustive. Many concepts are mentioned and referenced but not explained fully due to space constraints. The research suggests the future use of VR systems in FM solutions.

This paper discusses immersive virtual reality (VR) in support of building design tasks as an innovative tool, enabling more effective facilities management input at the building design phase.

The paper is based on original research. The paper explains and reviews the uses and potential uses of VR systems.

In any distributed application, the communication between the distributed processes/nodes of the distributed systems is essential for both reliability and efficiency matters. The purpose of this paper is to address this issue for distributed applications based on JXTA protocols aiming at extending and evaluating the protocols of the JXTA library for reliable P2P computing.

After a careful examination of the current version of JXTA protocols, the need was observed for improving the original JXTA protocols such as pipe services to ensure reliable communication between nodes of the grid platform and the discovery and presence service to increase the performance of the applications. Using a mixed P2P network based on broker peers and client peers architecture, which served as a basis to extend the JXTA protocols, was the basis of the approach.

The original JXTA protocols are extented/re‐implemented to support the development of reliable P2P distributed applications.

The proposed approach has been validated in practice by deploying a P2P network using nodes of PlanetLab platform and testing each of the re‐implemented protocols using this real P2P network. The extended JXTA protocols can be used to develop reliable P2P distributed applications.

Is of value by showing how to improve both efficiency reliability of JXTA protocols and services.

This paper aims to present a knowledge-based fuel system, implementation and application, oriented towards its use in aircraft conceptual design.

Methodology and software tools oriented to knowledge-based engineering applications (MOKA) is used as a foundation for the implementation and integration of fuel systems.

Including fuel systems earlier in the design process creates an opportunity to optimize it and obtain better solutions by allocating suitable locations in an aircraft, thereby reflecting on the centre of gravity of the aircraft.

All geometries are symbolic, representing a space allocation inside the aircraft for the fuel system. A realistic representation of the real components could be realized in detail design.

Fuel weight is a significant part of take-off weight and decisive in aircraft sizing and range estimations. The three-dimensional geometry provides a better estimation of the volume that is available to allocate the necessary entities. It also provides fast measures for weight and balance, fuel capacity, relative tank positions and a first estimation of piping length.

Fuel systems appear early in the design process, as they are involved in several first estimations. By using a knowledge-based engineering approach, several alternatives can be visualized and estimated in the conceptual design process. Furthermore, using the weights and centre of gravity at different angles of pitch and roll of each fuel tank, the aircraft could be optimized for handling qualities by using automatically generated system simulation models.

This paper outlines some of the background of and constraints facing the emergence of a new industry, focused not on buildings as such but on residential fit-out – the integrated kit-of-parts “behind your front door.” Residential application of the distinction between base building (support) and fit-out (infill), although sharing the same principles as the well-established office building and shopping mall sectors, is particularly important because it affects a very large market whose potential is not yet exploited but is arguably nascent.

It is well understood that industrial manufacturing processes – now becoming “product service systems” in the consumer sector – are most effective and dynamic where individual users are directly served, as seen in the automotive and electronics/communications sectors. Construction of base buildings understood as “infrastructures for living” is capable of stimulating the evolution of a fit-out industry that will itself accelerate innovation and distribution of new domestic fit-out services and systems.

In general, the creation of a genuine fit-out industry is not a technical or industrial design problem. Material subsystems and components like partitioning, bathroom and kitchen equipment, as well as “plug-and-play” piping and wiring are available or are being invented and approved in regulatory regimes internationally. While some smart products are still needed, the problem now is essentially a business proposition. By shifting to the provision of benefits rather than simply manufacturing products, companies may find a competitive advantage in a sector of the building industry now poised for an innovation leap. In the US and other developed countries, this is particularly compelling given the sustainability agenda, smart growth and increased demand for consumer-oriented production. In this perspective, the trend toward base building architecture allows the building industry to effectively come to terms with new and creative modes of industrial production.