Identifying subassemblies and understanding their functions during a design review in immersive and non-immersive virtual environments

Design review (DR) is a product development (PD) activity used to inspect the technical characteristics of a design solution. Immersive virtual reality (IVR) technology enables the presentation of spatial information and interaction with 3D CAD models inside an immersive virtual environment (IVE). Such capabilities have shown the potential to mitigate the cognitive load needed for the visual perception of spatial information and, consequently, enhance design understanding and DR performance. Thus, an increasing number of studies have explored the effect of IVR technology on DR activities in different domains. However, determining when the implementation of IVR technology rather than a conventional user interface for DRs in mechanical engineering PD projects will be beneficial remains unclear. Hence, a conceptual DR experimental study was conducted to investigate the differences in the ability of engineering students to identify mechanisms and understand their functions when a design solution for a technical system is presented in an IVE by IVR technology and in a non-immersive virtual environment (nIVE) by a conventional user interface (monitor display, keyboard, and mouse). Data were collected by performing DR tasks and having participants complete a prior experience questionnaire, presence questionnaire, and mental rotations test. Findings of the study indicate that IVR does not support an enhanced ability of engineering students to identify mechanisms and understand their functions compared with a conventional user interface.     

Automatic analysis of multiparty meetings

This paper is about the recognition and interpretation of multiparty meetings captured as audio, video and other signals. This is a challenging task since the meetings consist of spontaneous and conversational interactions between a number of participants: it is a multimodal, multiparty, multistream problem. We discuss the capture and annotation of the Augmented Multiparty Interaction (AMI) meeting corpus, the development of a meeting speech recognition system, and systems for the automatic segmentation, summarization and social processing of meetings, together with some example applications based on these systems.     

Application of Damage Tolerance principles to the design of helicopters

The design of helicopters against fatigue phenomena is a particularly important and complex problem, due to the peculiar load spectra, composed by a high number of low-amplitude cycles.The fatigue design methodology most commonly applied by the helicopter community was based on the Safe-Life philosophy, applied anyhow with a particular approach. Since 1989, the Airworthiness Regulations evolved towards the application of Damage Tolerance principles also to rotorcraft. This change has forced the helicopter industries to review their design methodologies, and to face new problems, linked with fracture mechanics applications to their typical structures. Flaws, accidental damages and manufacturing discrepancies must be accounted for, in addition to the retirement life based on Safe-Life.The paper reviews the current requirements and presents and discusses the methodologies that the helicopter industry adopts for demonstrating compliance with such regulatory requirements. In addition, recommendations are given on research and development activities required for refining the defined methodologies and for their better implementation.     

Adaptive improved response surface method for reliability-based design optimization

Reliability-based design optimization (RBDO) requires the evaluation of probabilistic constraints (or reliability), which can be very time consuming. Therefore, a practical solution for efficient reliability analysis is needed. The response surface method (RSM) and dimension reduction (DR) are two well-known approximation methods that construct the probabilistic limit state functions for reliability analysis. This article proposes a new RSM-based approximation approach, named the adaptive improved response surface method (AIRSM), which uses the moving least-squares method in conjunction with a new weight function. AIRSM is tested with two simplified designs of experiments: saturated design and central composite design. Its performance on reliability analysis is compared with DR in terms of efficiency and accuracy in multiple RBDO test problems.     

Research,technology and development evaluation; developments in Japan

The reseach, technology and development (RTD) evaluation in terms of science and technology policy has come to be important in stimulating research activities and in continuously keeping the vitality and the higher quality of research in RTD institutions. There are two criteria on the RTD evaluation, i.e, in-house evaluation from the stand point of RTD management and independent macroscopic evaluation for the decision making of companies and/or policy making for science and technology policy.The most important point for RTD evaluation in the former criteria is in the mission itself. RTD in universities, public research institutes, and enterprises have different objectives and characteristics. Therefore, the mission and methodology of RTD evaluations should be different, by categorized type and objectives of research institutions, and be developed inhouse. Results of RTD evaluations should be fed back to researchers or engineers and disclosed principally if the mission was to stimulate knowledge creation through RTD activities.The in-house RTD evaluation can be classified in general into three categories: prior evaluation, mid-term review, and ex-post facto review. The methodologies to evaluate RTD in each phase of the RTD process are different, even among those institutes categorized into the same type such as national and regional research institutes. In this paper, two cases of RTD evaluation a) in Riken, which was founded in 1917 as a private research foundation and later reorganized as a semi-public research corporation of the Science and Technology-Agency, b) in regional public research institutes.RTD evaluation from the view point of policy assessment of governmental science and technology policy is discussed through analysis of data obtained by the survey of research activities in regional public research institutes. It can be concluded that developments and introduction of RTD evaluation as a new management system in these institutes is improving the research environment and advancing the quality of research. The differences of RTD evaluation between a Center of Excellence (COE) such as Riken and local technology centers, will be compared and the policy implication of RTD evaluation will also be discussed in terms of promotion of science and technology.     

The methodologies of hazardous materials transportation risk assessment

Intense interest now exists in the potential of risk assessment as an aid to public and private decision making on hazardous activities. Inadequacies in its methodologies and supporting data have nevertheless so far limited its efficacy in practice. Among attacks on the problem of improving this efficacy is a project supported by the National Science Foundation which identifies and focuses on improvements in particular areas of uncertainty in risk assessment methodologies. This paper presents some of the project's material that pertains to hazardous materials transportation. It overviews the general risk assessment problem, presents a structured review of the types of methodologies employed in estimating the contribution to risk of the different phases of a hazardous material incident, and then reviews the procedures available for the evaluation of the significance of the risks estimated, and of potential means for their mitigation. Comments are made throughout, and in the paper's conclusions, on the problems arising in these estimation and evaluation processes, and on general approaches to their resolution.     

‘Signposting’, A Parameter-driven Task-based Model of the Design Process

This paper addresses the need for computer support in aerospace design. A review of current design methodologies and computer support tools is presented, and the need for further support is discussed, with particular reference to the early formative stages of the design process. A parameter-based model of design is proposed, founded on the assumption that a design process can be constructed from a predefined set of tasks. This is supported by knowledge of possible tasks in which the confidence in key design parameters is used as a basis for identifying, or signposting, the next task. A prototype implementation of the signposting model, for use in the design of helicopter rotor blades, is described and results from trials of the tool are presented. Further areas of research are discussed.     

A unified parametric design approach to structural shape optimization

This paper presents a general parametric design approach for 2-D shape optimization problems. This approach has been achieved by integrating practical design methodologies into numerical procedures. It is characterized by three features: (i) automatic selection of a minimum number of shape design variables based on the CAD geometric model; (ii) integration of sequential convex programming algorithms to solve equality constrained optimization problems; (iii) efficient sensitivity analysis by means of the improved semi-analytical method. It is shown that shape design variables can be either manually or systematically identified with the help of equality constraints describing the relationship between geometric entities. Numerical solutions are performed to demonstrate the applicability of the proposed approach. A discussion of the results is also given:     

Pushing thermoelectric generators toward energy harvesting from the human body: Challenges and strategies

Advances in miniaturized portable electronics and progress on novel enabling technologies, consequently accompanied by power consumption downgraded from the scale of milliwatts (mW) to microwatts (μW), have inevitably facilitate the development of an emerging discipline-wearable human energy conversion systems. Served as a passive human energy harvester which can directly convert heat into electricity in long-term operations without the user’s intervention, wearable thermoelectric generators (WTEG) have sparked considerable research interest for next-generation power supply. In comparison to the longstanding research history of thermoelectrics, their wearables are still in infancy of extensive growth over the last decade. Although, historically, the main challenge behind the conventional thermoelectric generator (TEG) is the improvement of dimensionless figure-of-merit (zT), wearable applications usually impose additional restrictions that can be more pivotal than zT value. Diversified targeted strategies therefore have been proposed to push TEG toward wearable application. Here, we review the evolutionary roadmap of the wearable thermoelectric generators in the past decade, it could be concluded that the trend in WTEG is to move toward stretchable three-dimension (3D)-structure with rational thermal design at the moment. The basic concept targeting WTEG, which highly differs from that of the traditional TEG, is introduced at first. And then, aiming to provide detailed design guidelines for WTEG, we begin with carefully discussing the key issues for TEG toward wearable application. Finally, the specific strategies targeted WTEG that is classified into thermal design regarding extrinsic temperature difference (ΔT_ext), parasitic and TEG thermal resistance, mechanical design with emphasis on optimizing deformability at materials/device level beyond flexibility toward stretchability, as well as architecture design from two-dimension (2D) to 3D feature are comprehensively summarized, respectively. With these understandings, perspectives for the future development of WTEG are outlined. This review emphasizes issues and provides additional insight in advanced strategies for pushing TEG toward wearable application. The key issues clarified and the design roadmap summarized here arise from the goal of providing ideas for the concurrent optimization of the future WTEG, as well as realistically promoting the TEG toward wearable application.     

Accuracy of inter-researcher similarity measures based on topical and social clues

Scientific literature recommender systems (SLRSs) provide papers to researchers according to their scientific interests. Systems rely on inter-researcher similarity measures that are usually computed according to publication contents (i.e., by extracting paper topics and citations). We highlight two major issues related to this design. The required full-text access and processing are expensive and hardly feasible. Moreover, clues about meetings, encounters, and informal exchanges between researchers (which are related to a social dimension) were not exploited to date. In order to tackle these issues, we propose an original SLRS based on a threefold contribution. First, we argue the case for defining inter-researcher similarity measures building on publicly available metadata. Second, we define topical and social measures that we combine together to issue socio-topical recommendations. Third, we conduct an evaluation with 71 volunteer researchers to check researchers’ perception against socio-topical similarities. Experimental results show a significant 11.21% accuracy improvement of socio-topical recommendations compared to baseline topical recommendations.     

Reliability Engineering Practice in the Light Duty Dodge Ram Truck Chassis Program

In this paper, we demonstrate how we set up and executed an integrated reliability engineering process with the engineering team in the Light Duty (LD) Dodge Ram (DR) Truck chassis program. Organizationally, the LD DR chassis team consists of core engineering groups and supporting representatives from other related disciplines. The reliability engineer is a member of the team and he is the reliability advocate and leader. The integrated reliability engineering process was customized and implemented in the LD DR chassis program. Many of the tools developed by the company corporate quality office, such as design failure modes and effect analysis (DFMEA), design verification plan and reporting (DVP&R), and finite element analysis (FEA), were used in supporting the reliability engineering process. An array of technical enablers such as Test Matrix and ReliUp were also developed for supporting the implementation of the reliability engineering process. In the execution, the reliability engineer led the engineering team to set up reliability targets, develop reliability work plans, facilitate up‐front design analysis, review and integrate reliability test planning. The reliability engineer also set up the failure reporting, analysis and corrective action system (FRACAS) and managed reliability growth with the team. From the implementation, we have learned several things: (1) an integrated engineering team is crucial in order to develop a product better, quicker and cheaper; (2) a good team leader is the key to product reliability; (3) a capable reliability engineer is the catalyst to a reliability engineering process; (4) the best culture in which to achieve reliability is the delicate balance between ‘inside‐out’ and ‘outside‐in’; and (5) achieving reliability is far more important than measuring reliability. Copyright © 2004 John Wiley & Sons, Ltd.     

From loop structure to policy-making: a CONWIP design framework for hybrid flow shop control in one-of-a-kind production environment

A feasible constant work in process (CONWIP) policy can guide developer to better implement CONWIP system. The feasible policy should be selected from alternatives by evaluation. Therefore, how to generate more than one CONWIP alternative policy to evaluate is an inevitable problem in CONWIP practice. From the perspective of loop structure, we propose CONWIP design framework (CDF) which is a systematic design approach to obtain CONWIP alternative policies. The basic concepts and components for CDF are discussed in this paper. Based on CDF, we make 10 CONWIP alternative policies for hybrid flow shop in one-of-a-kind production environment, and these alternative policies are evaluated by simulation. The simulation result implies that (i) the CONWIP alternative policy with robustness has the potential to cope with more fluctuations in high-variety production environment; (ii) a better design for CONWIP policy will be able to enhance the system performance in practice; and (iii) the loop structure can serve as a parameter of CONWIP.     

A comprehensive understanding of lowly-hydrolyzed polyvinyl alcohol-based ternary solid dispersions with the use of a combined mixture-process design

Abstract

We recently reported lowly hydrolyzed polyvinyl alcohol (L-PVA, 70–74% hydrolyzed, about 580 polymerized, JR-05) as a promising matrix for hot-melt extrusion (HME) due to its unique micelle formation ability compared to the most commonly used PVA (87–89% hydrolyzed, about 580 polymerized). In the present study, we focused on the effect of composition [indomethacin (IND), L-PVA, sorbitol] and process parameters (temperature and screw speed) on each response, i.e. processing torque, and physicochemical properties such as residual crystallinity, residual ratio, and area under the dissolution curve (AUDC) in supersaturated solution using a HME by applying the design of experiment (DoE) approach. To overcome the poor processability of L-PVA, given its semicrystalline nature, we applied sorbitol as a plasticizer and systematically and simultaneously evaluated its influence on the outputs based on the mixture design combined with process factors. Few studies have focused on comprehensive evaluation of the composition and HME process conditions because obtaining a design space requires numerous experiments. We found that incorporating sorbitol into the L-PVA greatly improved the processing torque. However, sorbitol negatively influenced the degree of residual crystallinity and the AUDC of IND. Lastly, we established a laboratory-scale design space that could achieve high supersaturation and ensure adequate miscibility between each component, using an acceptable processing torque for HME, by applying the minimum amount of sorbitol. These fundamental results suggest that sorbitol maximizes the potency of L-PVA as a carrier in HME.     

Tapping into past design experiences: knowledge sharing and creation during novice–expert design consultations

Designing is a knowledge-intensive activity. For novice design engineers, an important means of acquiring knowledge is to consult experienced colleagues. We observed novice?Cexpert consultations as part of three engineering projects in a large aerospace company. Seven meetings were analysed in detail regarding the design activity, the content, and the form of interaction. Although the meetings were initiated for the purpose of information seeking, this process amounted to only 8% of the time compared to knowledge creation between novices and experts (47% of meeting time), and contextual information sharing (45% of meeting time). Both experts and novices were found to contribute equally and interactively to the discussion and analysis of solutions. The analysis showed how the processes alternated in the meetings. We identified tentative patterns on how these consultation processes change over the course of the design process phases. The micro-level analysis of the design activities and form of interaction provided a deeper understanding of how the consultation processes are discursively produced by the experts and novices. Finally, implications for design engineering practitioners are derived and suggestions for further research are provided.     

Review of semantic modelling technologies in support of virtual factory design

Comprehensive data models and standardised terminologies are required across tools and their developers to rapidly design and prototype digitised virtual factories. Also, various types of software are required to be integrated for cost-effective modelling exercises. To meet this requirement, semantic modelling technologies involving ontologies have featured prominently in many manufacturing applications. This paper considers, extensively, the current semantic requirements for digitised virtual factory design and prototyping and compares them with the capabilities of existing semantic technologies. As a result, a review of methodologies, tools and languages for creating ontologies has been reported. The review concludes with the next generation requirements for methodologies, tools and languages for creating ontologies suitable for the virtual factory design process, and further explains ongoing work associated with the creation of ontologies and reasoning mechanisms through the integrated use of ObjectLogic, OntoStudio and OntoBroker.     

关于工程图学课程的教学设计

根据教学设计的理论,结合工程图学课程的特点,论述了在工程图学课程的教学设计过程的 3 个阶段(前期分析、教学设计、教学效果的评价)中所采用的方法,以及在教学设计中关于教学目标确立、教学过程及策略的设计、教学媒体的选择和教学节奏的安排等方面,应考虑的一些因素及重点问题的处理。并以一节课的内容为例,给出了教学过程的实例。     

A new methodological framework for design for additive manufacturing

Additive manufacturing (AM) offers numerous benefits for innovative design solutions. However, engineers are currently not supported in identifying and incorporating these potentials systematically in their design solutions. In this paper, previous Design for Additive Manufacturing (DfAM) approaches are first reviewed comprehensively and classified into distinct categories according to their main purpose and application. They are then analysed further by being related to conventional design methodologies like VDI 2221. Since previous DfAM approaches only provide selective assistance at single steps in the product development process, a new framework for DfAM is proposed. Existing methods and tools, both from DfAM and from general design methodologies, are integrated into the modular framework structure. A concept for using the framework is presented to provide design engineers with continuous support in all product development phases, thereby fostering the complete exploitation of AM potentials and the development of AM-conformal designs.     

Structure and Matrix Models for Tolerance Analysis from Configuration to Detail Design

A substantial amount of all quality problems that arise during assembly can be referred back to the geometrical design, and especially the geometrical concept of the product, i.e. the way in which parts are designed and located with each other. Special emphasis should thus be put on geometry design, especially during the early design phases, to try to find robust concepts and avoid solutions that may cause down-stream production problems.  This paper presents a generic set of evaluation tools for robust geometry design encountering (i) potential tolerance chain detection in configuration design, (ii) assembly robustness evaluation in concept design, and (iii) tolerance sensitivity analysis in detail design. Special attention is given to the development of a new matrix-based evaluation tool for the configuration design part. The tool presented is based on a new way of representing geometry variation constraints in an enhanced function-means tree structure model. Different parts of the function-means tree that are of interest for analysis purposes are then extracted and converted to matrix representation. The reason for doing this is that the structure model is most suitable for modeling, but becomes unsuitable for analysis as the model complexity increases. For this latter purpose, the matrix representation is far better. The use of the different tools is demonstrated in the design of a new vehicle front system for which the geometry a priori is unknown.     

A treatise on order in engineering design research

Engineering design research shows a rather fragmented, if not a chaotic, picture. But does it have a hidden order? Can we explore it, or should we impose a reasoning model? This paper looks for the answer in the purpose of engineering design. It is destined to sustain human existence and well being by virtual creation of artifacts and services for the society. To this end, the engineering design discipline should provide a proper body of knowledge. The design knowledge obtained by empirical exploration and/or rational comprehension should be transformed for practical/pragmatic deployment. It was assumed that this purposely streaming of design knowledge gives a unique rationale for engineering design research. Based on this, a framework of reasoning was constructed, including source, channel, and sink categories of knowledge and research of engineering design, respectively. Within each category, research domains, trajectories, and approaches were identified. The semantic relationships of domains, trajectories, and approaches form a hierarchical structure. The proposed framework enables a grounded argumentation about the order of engineering design research, as well as about the articulation of the engineering design knowledge.     

基于层次分析法的儿童智能手表设计评价研究

目的解决产品设计方案后期评价问题。方法提出了一种基于层次分析法(AHP)的设计评估方法,首先将产品分解为若干待评价的指标并对其进行评价打分,整理数据并计算出各指标的权重值,最终得出各方案的综合得分进而排序。结果通过3款儿童智能手表的市场销售调查数据验证了该排序结果的准确性,为产品设计方案的有效评估提供了参考。结论将层次分析法引入设计评价中,可有效降低设计评价中待评估要素多、对评估者的经验知识依赖大、各因素与最终方案之间的影响关系难以判断等问题所带来的不利影响。