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The purpose of this paper is to propose a methodology for evaluating the hygrothermal performance of framed wall assemblies based on design limits. This methodology allows designers to evaluate wall assemblies based on their absolute performance rather than relative performance which is typically done for most hygrothermal analysis.

The approach in developing this methodology was to evaluate wall assemblies against three typical design loads (e.g. air leakage, construction moisture, rain penetration) and determine limits in minimum insulation ratio, maximum indoor humidity and maximum rain penetration rates. This analysis was performed at both the field area of the wall and at framing junctions such as window sills.

The findings in this paper shows example design limits for various wall assemblies in heating-dominated climates in North America. Design limits for wall assemblies with moisture membranes of different vapour permeance are provided for both the field area of the wall and at window sills. Discussions about the importance of 2D hygrothermal simulation and performance of vapour permeable sub-sill membranes are also provided.

This framework of hygrothermal analysis will enable designers to make better decisions when designing framed wall assemblies suitable to the local climate and interior specifications for their projects. It will also enable the development of a design tool that will allow designers to visually see the implications of certain design decisions and filter out designs that do not meet their design conditions.

In the context of crowdsourced new product development (NPD), the purpose of this paper is to investigate the optimal level of community involvement (CI) (e.g. zero, limited, and high) when creating products from the perspectives of both ordinary and advanced users. The authors also investigate the influence of design interest and need for social affiliation on users’ attitudes toward and willingness to use community co-design.

The authors conducted two survey studies using ordinary (Study 1, n=199) and advanced users (Study 2, n=131) to evaluate the co-designed T-shirts reflecting varying levels of CI (i.e. zero, limited, and high). The stimuli for both studies were the same and included ten sets of T-shirt co-designs generated from a CI crowdsourced website, Threadless. Fishbein’s (1963) multi-attribute attitude model was used to compute subjects’ overall attitude score toward the T-shirt co-designs.

Results showed both ordinary and advanced user groups rated the design quality of products reflecting limited CI lower than those of zero CI. Advanced users also rated the design quality and sales potential of products from limited CI lower than those of high CI. Further, advanced users indicated that products resulting from high CI reflected significantly better designs with regard to color, shape/line, size, general theme, and overall design as compared to products from limited CI. Design interest as well as need for social affiliation influenced users’ willingness to use community co-design and their attitudes toward a community co-design experience.

The research made an important differentiation between zero, limited, and high CI during the co-design process as well as between ordinary users and advanced users contributed to the extant literature addressing crowdsourcing in NPD.

We can define architectural design studios as environments of simulation. Within this simulation limitations of real life architectural problems are constructed, yet the constructed reality is far from the reality of existing practice.

In Architecture: Story of Practice, Dana Cuff, makes a sociological study of the architectural design practice and in the volume she discusses design studios as limited versions of the actual design practice. As compared to the actual practice in the studio the students are alone, there isn’t a multiplicity of actors involved in the process, and the design problems are clearly defined. Cuff points out to these shortcomings and provides guidelines to overcome them.

One of the shortcomings mentioned in Cuff’s study is that: design studios do not represent the variety of actors that are present in a real life situation. Cuff suggests to include representatives of different actors in the studio practice to overcome this. If the studio fails to support itself with a variety of actors, to compensate the short coming of actors, the instructors start taking the role of many possible participants of a design process. The instructors simulate: the user, the owner, the engineer, the contractor and so on so forth. This type of an approach in the design studios leads to a certain result: the ideological construct of the instructors becomes the foundation of the constructed reality of the studio.

This study explores the ideological construction of the design studio through active involvements with undergraduate students. Through the findings of two discussion sessions, students’ own ideological positions, their relationship with the external realities and limits imposed on such relations by the studio instructor’s own ideological stances are explored.

The problem of optimal design of pressure vessel heads to maximize limit load behaviour is presented. Incremental elasto‐plastic analysis is used and a formulation based on the finite element method is presented whereby an approximate design model is generated which can be optimized via sequential programming. Results are presented for torispherical head shapes and tables are provided in order to evaluate the influence of different geometrical forms on limiting pressure loads. The method is generally applicable and can be applied to the design of components which are required to exhibit limited plastification under increasing load.

The purpose of this study is to identify and evaluate the primary constraints that quantity surveying firms in Nigeria encounter while integrating indoor environmental quality (IEQ) principles into building designs.

The study used a quantitative approach by administering a well-structured questionnaire to 114 quantity surveyors. The collected data were analyzed using methods such as frequencies, percentages, mean item scores, Kruskal–Wallis test and exploratory factor analysis.

The top five ranked constraints were limited access to funding or financing options, limited availability of green materials, limited availability of insurance for sustainable buildings, limited availability of sustainable design resources and limited diversity and inclusivity within the design profession. Based on the factor analysis, the study identified six clusters of constraints: structural-related constraints, technical-related constraints, financial-related constraints, capacity-related constraints, legal-related constraints and culture-related constraints.

This study has several practical implications for quantity surveying firms, policymakers and industry stakeholders involved in building design and construction in Nigeria. The findings of this study can also inform future research on the integration of IEQ principles into building designs.

By identifying and structuring the clusters of constraints faced by quantity surveying firms in Nigeria when implementing IEQ principles, this study provides a novel approach to understanding the challenges associated with IEQ implementation in the building sector. This understanding can guide policymakers, industry stakeholders and quantity surveying firms in developing effective strategies to overcome these constraints and promote IEQ principles in building design and construction.

THE modern aeroplane is constructed largely from sheet metal. As such, the most important production problems are those of sheet metal forming, and assembling. Production is here considered as not only the act of forming and assembling the required number of parts, but also the making of forming tools, and all processing of parts such as heat‐treating. Only that phase of the above concept of production which deals with the tooling for production and the forming and heat‐treating will be considered here. The design of the aircraft parts will also be discussed somewhat, for it is obvious that the design of the part (designed shape and materials used) frequently determines whether the part can or cannot be readily made.

The traditional Shewhart control chart, the X-bar and R/S chart, cannot give support to decide when it is not economically feasible to stop the process in order to remove special causes. Therefore, the purpose of this paper is to propose a new control chart design – a modified acceptance control chart, which provides a supportive method for decision making in economic terms, especially when the process has high capability indices.

The authors made a modeling expectation average run length (ARL), which incorporates the probability density function of the sampling distribution of C_pk, to compare and analyze the efficiency of the proposed design.

This study suggested a new procedure to calculate the control limits (CL) of the X-bar chart, which allows economic decisions about the process to be made. By introducing a permissible average variation and defining three regions for statistical CL in the traditional X-bar control chart, a new design is proposed.

A framework is presented to help practitioners in the use of the proposed control chart. Two new parameters (C_p and C_pk) in addition to m and n were introduced in the expected ARL equation. The C_pk is a random variable and its probability function is known. Therefore, by using a preliminary sample of a process under control, the authors can test whether the process is capable or not.

The purpose of this study is to enable performing reliability-based design optimisation (RBDO) for a composite component while accounting for several multi-scale uncertainties using a large representative volume element (LRVE). This is achieved using an efficient finite element analysis (FEA)-based multi-scale reliability framework and sequential optimisation strategy.

An efficient FEA-based multi-scale reliability framework used in this study is extended and combined with a proposed sequential optimisation strategy to produce an efficient, flexible and accurate RBDO framework for fibre-reinforced composite laminate components. The proposed RBDO strategy is demonstrated by finding the optimum design solution for a composite component under the effect of multi-scale uncertainties while meeting a specific stiffness reliability requirement. Performing this using the double-loop approach is computationally expensive because of the number of uncertainties and function evaluations required to assess the reliability. Thus, a sequential optimisation concept is proposed, which starts by finding a deterministic optimum solution, then assesses the reliability and shifts the constraint limit to a safer region. This is repeated until the desired level of reliability is reached. This is followed by a final probabilistic optimisation to reduce the mass further and meet the desired level of stiffness reliability. In addition, the proposed framework uses several surrogate models to replace expensive FE function evaluations during optimisation and reliability analysis. The numerical example is also used to investigate the effect of using different sizes of LRVEs, compared with a single RVE. In future work, other problem-dependent surrogates such as Kriging will be used to allow predicting lower probability of failures with high accuracy.

The integration of the developed multi-scale reliability framework with the sequential RBDO optimisation strategy is proven computationally feasible, and it is shown that the use of LRVEs leads to less conservative designs compared with the use of single RVE, i.e. up to 3.5% weight reduction in the case of the 1 × 1 RVE optimised component. This is because the LRVE provides a representation of the spatial variability of uncertainties in a composite material while capturing a wider range of uncertainties at each iteration.

Fibre-reinforced composite laminate components designed using reliability and optimisation have been investigated before. Still, they have not previously been combined in a comprehensive multi-scale RBDO. Therefore, this study combines the probabilistic framework with an optimisation strategy to perform multi-scale RBDO and demonstrates its feasibility and efficiency for an fibre reinforced polymer component design.

The present study is based on finding the structural response of a tensile membrane structure (TMS) through deformation. The intention of the present research is to develop a basic understanding of reliability analysis and deflection behavior of a pre-tensioned TMS. The mean value first-order second-moment method (MVFOSM) method is used here to evaluate stochastic moments of a performance function with random input variables. Results suggest the influence of modulus of elasticity, the thickness of the membrane, and edge span length are significant for reliability based TMS design.

A simple TMS is designed and simulated by applying external forces (along with prestress), as a manifestation of wind and snow load. A nonlinear analysis is executed to evaluate TMS deflection, followed by calculating the reliability index. Parametric study is done to consider the effect of membrane material, thickness and load location. First-order second moment (FOSM) is used to evaluative the reliability. A comparison of reliability index is done and deflection variations from μ − 3s to μ + 3s are accounted for in this approach.

The effectiveness of deflection is highlighted for the reliability assessment of TMS. Reliability and parametric study collectively examine the proposed geometry and material to facilitate infield design requirements. The estimated β value indicates that most suitable fabric material for a simple TMS should possess an elasticity modulus in the range of 1,000–1,500 MPa, the thickness may be considered to be around 1.00 mm, and additional adjustment of around 5–10 mm is suggested for edge length. The loading position in case of TMS structures can be a sensitive aspect where the rigidity of the surface is dependent on the pre-tensioning of the membrane.

The significance of the parametric study on material and loading for deflection of TMS is emphasized. Due to the lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for researchers.

The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.

The significance of parametric study for serviceability criteria is emphasized. Parameters like pre-stress can be included in future parametric studies to witness in depth behavior of TMS. Due to lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for the researchers. The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.

The purpose of this paper is to identify the dominant strategy and business models of companies and to analyse the awareness of design and the stage of design application in business in its broader sense from the perspective of business executives in the manufacturing sector and professional designers in the design industry that lead to creating successful business models in Latvia and Estonia.

The questionnaire was used with two target groups – business executives (based on NACE 2, B-E sections, i.e. manufacturing companies) and professional designers in the design industry (NACE 2, M 74.10 section). In the first target group, 374 responses of business executives in Latvia and 371 responses of business executives in Estonia were received; in the second target group, 85 respondents in Latvia and 42 respondents in Estonia providing professional design services were analysed to identify the level of design awareness and its application in business in the respective countries.

There are national and regional specifics in Latvia and Estonia based on the development level of micro and macro factors that influence the entire innovation ecosystem. When comparing both countries in these terms, both target groups specify that design is applied more frequently in the processes of product development in Estonia, thus leading to new forms of innovation, than it is in Latvia. Conversely, in Latvia, many business managers still focus on short-term business solutions and cost-reduction as a sole challenge, with limited awareness of management approaches based on the broader application of design as a powerful innovation source for product development, improvement, and renewal of business models.

A suggestion for further research is to replicate the study in Lithuania and explore the perspective of other stakeholders.

The results of this research demonstrate the necessity to change the thinking patterns of business managers in order to develop their skills and capabilities to recognize emerging new driving forces of innovation unfolding through awareness of design and opportunities for its extended application that create successful business models for continuous value generation.

This paper makes a contribution to understanding the current stage of awareness of design and its application in the manufacturing sector in the Baltic States.