Experimental study on the effects of visualized functionally abstracted information on process control tasks

Two distinct design problems of information display for process control are information content representation and visual form design. Regarding information content, we experimentally showed the effectiveness of functionally abstracted information without the benefits of sophisticated graphical presentation in various task situations. However, since it is obvious that the effects of the information display are also influenced by display formats (i.e., visual forms) as well as the information content, further research was required to investigate the effectiveness of visualized functionally abstracted information. For this purpose, this study conducted an experiment in complex process control tasks (operation and fault diagnosis). The experimental purposes were to confirm the effectiveness of the functionally abstracted information visualized with emergent features or peculiar geometric forms and to examine the additional effects of the visualization on task performance. The results showed that functionally abstracted information presented with sophisticated visual forms helped operators perform process control tasks in more efficient and safe way. The results also indicated the importance of explicit visualization of goal–means relation between higher and lower abstraction levels. Lastly, this study proposed a framework for designing visual forms for process control display.     

All at Sea with User Interfaces: From Evolutionary to Ecological Design for Submarine Combat Systems

The quickening pace of technological advancement will require submarine command teams of the future to process greater volumes of data, potentially with fewer operators. User interfaces (UIs) have evolved to meet current requirements, but this iterative process has propagated legacy design paradigms that may be unsuitable for future system specifications. To understand where improvements may be made, a review of current submarine control room operation is presented, using a sociotechnical systems approach. The social (command team: work, structure, and communication) and technical (combat systems) components are presented for context. An emphasis is placed on Sonar and Target Motion Analysis due to their prevalence within the control room. It was found that current UIs place increased cognitive requirements on operators due to the complexity and quantity of information presented. It is proposed that adopting an Ecological Interface Design (EID) approach could reduce such issues, facilitating effective resource allocation to manage increased data volumes. EID has been demonstrated to be effective across many domains, however, its exploitation in submarine control rooms is limited. Advances in modern submarine combat systems have promoted greater flexibility, providing an opportunity to utilise contemporary design philosophies for designing intuitive interfaces to maintain effective control room performance.     

Gaussian beam and pulsed-beam dynamics: complex-source and complex-spectrum formulations within and beyond paraxial asymptotics.

Paraxial Gaussian beams (GB's) are collimated wave objects that have found wide application in optical system analysis and design. A GB propagates in physical space according to well-established quasi-geometric-optical rules that can accommodate weakly inhomogeneous media as well as reflection from and transmission through curved interfaces and thin-lens configurations. We examine the GB concept from a broad perspective in the frequency domain (FD) and the short-pulse time domain (TD) and within as well as arbitrarily beyond the paraxial constraint. For the formal analysis, which is followed by physics-matched high-frequency asymptotics, we use a (space-time)-(wavenumber-frequency) phase-space format to discuss the exact complex-source-point method and the associated asymptotic beam tracking by means of complex rays, the TD pulsed-beam (PB) ultrawideband wave-packet counterpart of the FD GB, GB's and PB's as basis functions for representing arbitrary fields, GB and PB diffraction, and FD-TD radiation from extended continuous aperture distributions in which the GB and the PB bases, installed through windowed transforms, yield numerically compact physics-matched a priori localization in the plane-wave-based nonwindowed spectral representations.     

Unified representation of fixtures: clamping,locating and supporting elements in CNC manufacture

A CNC machining operation is the outcome of the application of the integrated capabilities of various resources within the CNC machining centre. Part fixtures, clamping and other location mechanisms are essential subsets of CNC machining resources. Today, various fixturing techniques and attachments available in the market allow manufacturers to enhance their production capability without buying expensive machine tools. This technology-rich fixturing domain is detached while representing and exchanging machine tool resource information for making manufacturing decisions. The research work in this article utilises the STEP-NC compliant unified manufacturing resource model (UMRM) for representing fixtures in conjunction with the parent CNC machining centre. Thus, UMRM is enhanced in this context to represent various fixtures such as universal vises, chucks, pallets and auxiliary rotary tables among others. The major contribution of this article is the application of the extension of the UMRM approach for representing fixturing domain, which allows generic modelling of fixtures and loading devices in addition to machine workpiece and process modelling. This would enable the stage of automated process planning and manufacturing. The universal approach in representing resource information allows the data to be utilised for making a wide variety of manufacturing decisions.     

Multi-material plastic part design via the level set shape and topology optimization method

This work presents a new multi-material level set topology optimization method which is developed especially for designing plastic parts. Instead of representing the structure using multiple level set functions, this new method employs only one level set function to describe the material/void interface. The injection moulding filling simulation is used to determine the material/material interfaces. Because plastic parts are targeted, domain-specific knowledge is carefully investigated to improve the optimization algorithm. Both homogeneous and heterogeneous fibre-reinforced plastics are considered as potential material phases. For the latter, one extra design freedom, fibre orientation distribution, is introduced. Instead of generating incremental interior voids, which complicates the mould design and part ejection, shape-fixed interior voids could be predefined inside the design domain for functional or assembly purposes. This is represented by an additional level set function. A few numerical examples are studied to demonstrate the effectiveness of the proposed method.     

Graphene foam resonators:Fabrication and characterization

Three-dimensional graphene foams(GFs)benefit from a large surface area and unique physical properties.We present here the first-ever miniaturized GF-based resonators.We developed a simple yet reliable fabrication process,in which GFs are synthesized and assembled on a cavity to form suspended GF devices.We electrostatically excited these devices and analyzed their resonance and ring-down responses.We observed significant energy dissipation,as the quality factor of the devices was in the order of several tens.Additionally,we investigated the influence of temperature on the operation of the devices and found that high temperatures mechanically soften the resonators but also considerably enhance energy dissipation.Finally,our devices demonstrated a mode-coupling of a resonance mode and a mode having twice its frequency.Thus,this work paves the way toward the development of novel GF resonators that could be integrated into future devices,such as GF-based nano-electromechanical sensors,electrical circuits,and oscillators.     

Laser metal deposition of functionally graded Ti6Al4V/TiC

Functionally graded materials (FGMs) are advanced materials with improved properties that enable them to withstand severe working environment which the traditional composite materials cannot withstand. FGM found their applications in several areas which include: military, medicine and aerospace. Various manufacturing processes are used to produce functionally graded materials that include: powder metallurgy, physical vapour deposition, chemical vapour deposition process and laser metal deposition process. Laser metal deposition (LMD) process is an additive manufacturing process that can be used to produce functionally graded material directly from the three dimensional (3D) computer aided design (CAD) model of the part in one single process. LMD process is a fairly new manufacturing process and a highly non-linear process. The process parameters are of great importance in LMD process and they need to be optimized for the required application. In this study, functionally graded titanium alloy composite was produced using optimized process parameters for each material combination as obtained through a model that was developed in an initial study and the FGM was characterized through metallurgical, mechanical and tribological studies. The results show that the produced FGM has improved properties when compared to those produced at constant processing parameters for all material combinations.     

A multiscale strategy for structural optimization

This paper presents a multiscale strategy dedicated to structural optimization. The applications concern the study of geometric details (such as holes, surface profiles, etc) within the structures with frictional contacts. The first characteristic of the method is that it uses a micro–macro approach. This approach is based on a domain decomposition into substructures and interfaces, which involves the resolution of independent ‘micro’ problems in each substructure and transfers ‘macro’ information only through the interfaces. The second characteristic is the use of a multiresolution strategy in order to reduce the computation cost for problems with evolving design parameters. The last characteristic is the capability to model the geometry of details without remeshing thanks to two features: the use of a local enrichment method , and the use of level set functions to easily modify the boundary of the detail during the optimization process. Copyright © 2008 John Wiley & Sons, Ltd.     

Self-assembled high-performance graphene oxide fibers using ionic liquid as coagulating agent

An efficient strategy for fabricating high-performance GO fibers (GFs) by using ionic liquids as coagulating agent via wet-spinning technique was reported for the first time. The interactions between the functional groups of the GO sheets and the ionic liquids cations could be tuned by choosing ionic liquids cations with designed structure, yielding GFs with varied mechanical properties. No organic solvent or postdrawing processes involved makes this process green and facile.     

孔子问答镜的文化特征提取与设计应用研究

目的将唐镜的元素运用到产品设计过程中,不仅满足目标对象对产品的多样性需求,而且也增强设计的故事性和内涵性。方法通过Kano模型用户需求分析,得到目标对象的主要需求;收集孔子问答镜的相关资料,提取孔子问答镜的显性文化特征和隐性文化特征;融合目标对象的主要需求,按照形状文法的规则演变,对提取的文化特征进行加工处理,得到可以直接应用的创意设计元素;并结合腕表设计案例对该方法进行实践验证。结论孔子问答镜文化特征提取与设计应用,既有利于提升现代人的品位,又实现了对中国传统文化的传承和创新。     

On enrichment functions in the extended finite element method

This paper presents mathematical derivation of enrichment functions in the extended finite element method for numerical modeling of strong and weak discontinuities. The proposed approach consists in combining the level set method with characteristic functions as well as domain decomposition and reproduction technique. We start with the simple case of a triangular linear element cut by one interface across which displacement field suffers a jump. The main steps towards the derivation of enrichment functions are as follows: (1) extension of the subfields separated by the interface to the whole element domain and definition of complementary nodal variables; (2) construction of characteristic functions for describing the geometry and physical field; (3) determination of the sets of basic nodal variables; (4) domain decompositions according to Step 3 and then reproduction of the physical field in terms of characteristic functions and nodal variables; and (5) comparison of the piecewise interpolations formulated at Steps 3 and 4 with the standard extended finite element method form, which yields enrichment functions. In this process, the physical meanings of both the basic and complementary nodal variables are clarified, which helps to impose Dirichlet boundary conditions. Enrichment functions for weak discontinuities are constructed from deeper insights into the structure of the functions for strong discontinuities. Relationships between the two classes of functions are naturally established. Improvements upon basic enrichment functions for weak discontinuities are performed so as to achieve satisfactory convergence and accuracy. From numerical viewpoints, a simple and efficient treatment on the issue of blending elements is also proposed with implementation details. For validation purposes, applications of the derived functions to heterogeneous problems with imperfect interfaces are presented. Copyright © 2012 John Wiley & Sons, Ltd.     

Three-dimensional analysis of a functionally graded coating/substrate system of finite thickness

The concept of functionally graded material (FGM) is currently actively explored in coating design for the purpose of eliminating the mismatch of thermomechanical properties at the interfaces and thus increasing the resistance of coatings to functional failure. In the present paper, three-dimensional elastic deformation of a functionally graded coating/substrate system of finite thickness subjected to mechanical loading is investigated. A comparative study of FGM versus homogeneous coating is conducted to examine the effect of the coating type on stress and displacement fields in the system.     

Applying cognitive work analysis to the design of rapidly reconfigurable interfaces in complex networks

The objective of this paper is to illustrate the interconnections between the different phases (or tools) within the cognitive work analysis framework; the benefits of extending an analysis across each of the five phases are highlighted through these interconnections. The paper uses a command and control micro-world example to describe how each of the five phases can be used to describe the constraints within the micro-world domain from a different perspective. Based upon the social organisation and cooperation analysis, design requirements are extracted in order to develop role specific customisable interfaces for use within the micro-world. The interfaces have been specifically developed to communicate real time reconfiguration of the network through each of the individual interfaces; the reallocations of functions or roles are communicated to the actors through changes to the interface.     

集成AHP/QFD/AD的产品设计方法研究

目的针对以用户需求为驱动的产品设计模式,完善产品设计方法流程,更有效地理解用户需求,提高产品设计效率和质量。方法使用层次分析法确定用户需求权重,将用户需求及权重输入质量屋,对用户需求与设计需求的相关关系度进行量化评价,构建用户需求与设计需求相关关系矩阵,确定各项设计需求重要度,完成用户需求到设计需求的转化,以相对重要度较高的设计需求定义功能域,进行功能域与物理域之间的映射,利用独立性公理和信息公理进行设计参数分析和设计方案评价。结论构建了一种集成层次分析法、质量功能展开和公理化设计的产品设计方法,对用户需求权重进行了更准确的分析,完善了质量功能展开后续的方法流程,并以板栗采收机概念设计为例进行了应用验证,应用结果表明该方法能够有效地指导产品设计过程,提高产品设计效率和质量。     

用CVI工艺制备碳纤维增强C－SiC梯度热结构材料

用化学气相渗（ＣＶＩ）工艺，分别用分段沉积和共沉积方法制取了Ｃ／Ｃ－ＳｉＣ梯度热结构材料，并比较了二者的成分梯度、性能与组织结构特征。     

Processability and mechanical properties of surface-modified glass-fibres/phthalonitrile composite and Al–Li alloy fibre-metal-laminates

In this study, newly developed fibre-metal laminates (Al-LiFMLs) were prepared by a lay-up process of a high-performance surface-modified glass fibres/phthalonitrile (GFs/PN) composite and Al–Li alloy. The results showed that varying the composite considerably affected the tensile properties of the Al-LiFMLs, as well as exhibiting enhancements over the properties of both the individual Al–Li alloys and GFs/PN composite constituents. For instance, when the number of composite layers varied from 6 to 14, the ultimate tensile strength of the Al-LiFMLs increased from 315 to 611?MPa. It was revealed that the failure mode displayed a more ductile behaviour (up to 20%) for all the developed Al-LiFMLs affected by the ductile fracture mode of the Al–Li alloy.     

Synthesis of schematic descriptions in mechanical design

This article describes a schematic synthesis problem and one of its solution techniques. The problem domain consists of devices that can be described as networks of lumped-parameter, idealized elements in the translational-mechanical, rotational-mechanical, fluidmechanical, and electrical media. Such devices include speedometers, accelerometers, pneumatic cylinders, and pressure gauges. Design problems in this domain are specified by an input quantity, an output quantity, and the desired relationship between the input and output. The solution technique is based on three steps: 1) generate a candidate design, 2) derive and classify the behavior of the candidate, 3) based on the derived behavior and domain knowledge, modify the candidate (if possible) to bring it in line with the specification. The key idea behind this techniques is that an abstract characterization of the essential properties of the candidate design expedites the analysis and modification. The results of this work are aimed at computer tools for preliminary mechanical design.     

General information model for representing machining features in CAPP systems

Today, the generality of computer-aided process planning (CAPP) systems and their standardization do not achieve satisfactory standards levels for industry. One of the major causes here is the difficulty of integration with computer-aided design applications, due mainly to the product model used. It is therefore necessary to identify models that are general with regard to the products, but at the same time suitable for CAPP. A product model suitable for CAPP must represent the product conceptually, enabling the development of process planning functions that operate with manufacturing concepts. It is therefore necessary to develop product information models using this philosophy. The present paper focuses on this problem and proposes an information system for representing the product for internal CAPP use. It is geared towards representing all of the part information (necessary for manufacturing) integrally with the machining features and under the same concept as these features. To this end, one of the main characteristics of the model is the absence of conventional geometric entities. The application domain of the model proposed is the assignment of processes and machines in machined parts. The GF-CAPP system has revealed that the advantages of using this type of product model in CAPP are its generality with regard to the product and the ease of developing functional procedures that are general, simple and independent.     

Tailoring the Thermal and Mechanical Properties of Graphene Film by Structural Engineering

Due to substantial phonon scattering induced by various structural defects, the in‐plane thermal conductivity (K) of graphene films (GFs) is still inferior to the commercial pyrolytic graphite sheet (PGS). Here, the problem is solved by engineering the structures of GFs in the aspects of grain size, film alignment, and thickness, and interlayer binding energy. The maximum K of GFs reaches to 3200 W m^?1 K^?1 and outperforms PGS by 60%. The superior K of GFs is strongly related to its large and intact grains, which are over four times larger than the best PGS. The large smooth features about 11 µm and good layer alignment of GFs also benefit on reducing phonon scattering induced by wrinkles/defects. In addition, the presence of substantial turbostratic‐stacking graphene is found up to 37% in thin GFs. The lacking of order in turbostratic‐stacking graphene leads to very weak interlayer binding energy, which can significantly decrease the phonon interfacial scattering. The GFs also demonstrate excellent flexibility and high tensile strength, which is about three times higher than PGS. Therefore, GFs with optimized structures and properties show great potentials in thermal management of form‐factor‐driven electronics and other high‐power‐driven systems.