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The paper attempts to establish the connection between structural reliability and structural optimization for the particular case of plastic structures. Along this line, the paper outlines a reliability‐based optimization approach to design plastic structures with uncertain interdependent strengths and acted on by random interdependent loads. The importance of such interdependencies, and of some of the other statistical parameters used as input data in probabilistic computations, is demonstrated by several examples of sensitivity studies on both the probability of collapse failure as well as the reliability‐based optimum solution.

The behaviours of four indeterminate frame-support combinations namely Type I (with fixed supports), Type II (with pinned supports), Type III (with fixed-pinned supports) and Type IV (with fixed-roller supports) frames under the exposure conditions and loads as existing on site were simulated. Two categories of these combinations (I and II) were studied namely single storey-single bay and multiple storey-single bay frames, as illustrated in the case studies treated. A procedure for determining the probability of failure at different sections along the frame types, the range between the probability of failure bounds and the reliability ratings of the frame types were developed based on the kinetic method of plastic moment analysis, minimum weight design method, piecewise method of moment analysis and first order-second moment (FOSM) methods. The analysis results of the Category I frames showed that the Type I frame was most reliable (with the lowest probability of failure range of 0.3269), while the Type II frame was least reliable (with the highest probability of failure range of 0.4918). These results were consistent with those of the Category II frames. The paper aims to discuss these issues.

Collapse mechanisms were generated for four frame-support types and the corresponding plastic moments were determined using both the kinematic plastic analyses and minimum weight design methods. The members were designed and the plastic moments were distributed at sections of constant interval along the frame length to generate corresponding envelopes. A similar process was carried out to determine the elastic moment variables due to the loads. The reliability index and the corresponding probability of failure at each frame section were determined. Then, the probabilities of failure bounds for the frames were then compared to determine the most reliable.

It was observed that there existed a wide margin between the elastic and plastic moments indicating that design of steel structures at the elastic limit does not take full advantage of its strength. Hence, the design can be carried out beyond the elastic limit and within the safety margin given in equation (3). However, the safety of the entire frame is assessed on the basis of range of values between the highest and the lowest probability of failure bounds. The lower this range is (not exceeding 0.5 or 50 per cent), the more reliable the frame is.

The equations developed in this study can only be directly applied to multi storey-single bay frames. However, the reliability-based analysis and design procedure developed can be extended to other types of frames.

A practical approach for analysing steel frames with different supports with the overall goal of producing safe and economical designs has been developed and presented in this paper.

The procedure adopted is very original and can be backed up by existing literature. The piecewise method for analysing moments at various sections along a frame is also innovative. The whole concept can be adopted to determine the reliability of other types of frames such as multiple bay-multistorey frames with different support types.

In 2017, global plastic production reached 348 million tonnes. Despite growing concerns about the environmental challenges associated with both plastic production and plastic waste, recent estimates suggest that plastic production and subsequent waste is expected to double by the year 2035 (European Commission, 2018). To help reduce the amount of plastic waste that litters the oceans and damages the environment, the European Union has recently commissioned a study about the feasibility of levying a tax on plastic products (New Economic Foundation for the Rethink Plastic Alliance, 2018). However, very few academic articles currently exist that critically examine the arguments for or against a plastic tax and thereby enlighten government and regulators on the subject. This chapter investigates whether plastic taxes can be used as an economic disincentive for plastic products and explores its advantages and disadvantages within a circular economy. It explores whether a plastic tax is the right economic instrument to limit the use of plastics, generate design and technical innovations for bio-based materials and degradable/recyclable plastics, create other economic incentives to optimize the value of plastic and its waste collection, and increase public awareness and responsibility. We find that a plastic tax may be a suitable solution as it is likely to influence the design, production, consumption, and waste sectors if designed properly. Yet, the tax should be carefully implemented and combined with other instruments to obtain the desired outcomes and reduce the occurrence of unfavorable side effects.

This research study focuses on investigating the seismic performance of non-straight beams in steel structures and exploring the mechanism by which plastic hinges are formed within these beams. The findings contribute to the understanding of their behaviour under seismic loads and offer insights into their potential for enhancing the lateral resistance of the structure. The abstract of the study highlights the significance of corners in structural plans, where non-coaxial columns, diagonal elements or beams deviating from a straight path are commonly observed. Typically, these non-straight beams are connected to the columns using pinned connections, despite their unknown seismic behaviour. Recognizing the importance of generating plastic hinges in special moment resisting frames and the lack of previous research on the involvement of these non-straight beams, this study aims to address this knowledge gap.

This study examines the seismic behaviour and plastic hinge formation of non-straight beams in steel structures. Non-straight beams are beams that connect non-coaxial columns and diagonal elements, or deviate from a linear path. They are usually pinned to the columns, and their seismic contribution is unknown. A critical case with a 12-m non-straight beam is analysed using Abaqus software. Different models are created with varying cross-section shapes and connection types between the non-straight beams. The models are subjected to lateral monotonic and cyclic loads in one direction. The results show that non-straight beams increase the lateral stiffness, strength and energy dissipation of the models compared to disconnected beams that act as two cantilevers.

The analysis results reveal several key findings. The inclusion of non-straight beams in the models leads to increased lateral stiffness, strength and energy dissipation compared to the scenario where the beams are disconnected and act as two cantilever beams. Plastic hinges are formed at both ends of the non-straight beam when a 3% drift is reached, contributing to energy damping and introducing plasticity into the structure. These results strongly suggest that non-straight beams play a significant role in enhancing the lateral resistance of the system. Based on the seismic analysis results, this study recommends the utilization of non-straight beams in special moment frames due to the formation of plastic hinges within these beams and their effective participation in resisting lateral seismic loads. This research fills a critical gap in understanding the behaviour of non-straight beams and provides valuable insights for structural engineers involved in the design and analysis of steel structures.

The authors believe that this research will greatly contribute to the knowledge and understanding of the seismic performance of non-straight beams in steel structures.

As a measure against plastic waste, Coca-Cola and Evian have begun introducing label-free plastic bottles. Food labels have long been recognized as an important marketing tool, but there is a lack of research on label-free products. To address this gap, this study examined the influence of label-free design on product attractiveness in the Japanese green tea market.

If existing products are used in an experiment, respondents would be subject to brand image bias. Hence, by mechanically combining the main design elements (cap shape, bottle style, decoration line, logo and label) with an orthogonal array, the conditions for bottles with and without labels are completely aligned. The authors conducted an online survey and applied the chi-square test to the attractiveness of 18 designs presented in random order.

Label-free designs were more attractive to consumers than labeled designs. The effect was higher among female, middle-aged and older adults; those with higher annual income and low-frequency purchasers.

Practitioners should adopt a label-free design that can satisfy both environmental considerations and customer value. It would be a formidable challenge to change the longstanding emphasis placed on label design, but this study demonstrates the value of doing so.

This is the first study in the package design literature on the advantages of label-free plastic bottles. The authors also applied an orthogonal array used for many years to optimize objective numerical values in marketing research.

Although it is a well-known notion that “a family firm does not survive beyond the third generation”, owing to the ineffective tacit knowledge transfer, studies investigating the relationship between generational evolution and knowledge innovation is scarce. Thus, this case study revolving Sin Kwang Plastic Resources Berhad (SKP) seeks to address this gap in literature.

To assess the development of family business, a longitudinal case study was performed by documenting the entire evolutionary process starting from its establishment until now. The historical profiles for SKP were obtained from the previous annual reports submitted to the government's Companies Commission (SSM). Secondary materials from the Federation of Malaysian Manufacturers (FMM) and the edge newspaper and articles on the company were also gathered. Throughout the in-depth interviews, the author can see how the next generation of this family firm innovates and implements tacit knowledge innovation in original equipment manufacturing (OEM) by adhering to the Japanese industrial standards.

Findings show that the second generation utilized the company's extensive knowledge in plastic contract manufacturing in SKP for tacit knowledge conversion, triggers the birth of STS Tecnic Berhad, a subsidiary company that manufactures plastic parts for the industrial packaging and automotive industry. To simplify the process of managing the complex business, SKP opted to “prune the family tree” by dividing the business, involving fewer managers and restricting the number of family shareholders.

This case study traces how Gan's family's tacit knowledge in plastic contract manufacturing have been acquired from the experience of contract manufacturing with the Japanese multinational corporations (MNCs) by further commercializing the tacit knowledge into different companies for different plants. SKP promotes tacit knowledge innovation in the learning organization, thus responding to the firm's sustainability.

This study demonstrates that knowledge transformation plays vital roles in product development and gaining competitive advantage. The success of this business is founded by the building of shared values, norms and technical understanding in plastic contract manufacturing among the Japanese MNCs in Malaysia.

IN RECENT issues (April, Stopwatch and Book Reviews, June) we referred to the possibility of a factory where the sole human was a person pressing buttons at a control centre. All else was done by automation.

Retail shopping bags are a form of secondary packaging, which are provided by retailers (free of charge) to customers as a means of transporting merchandise. In Hong Kong, the reuse of shopping bags is a common phenomenon. What are the important reasons for consumers to use and reuse shopping bags? What are the usage frequencies of different kinds of shopping bags? There are no published studies relating to shopping bags, therefore, this exploratory study aims to provide an initial insight toward consumer perceptions of shopping bags. After qualitative work, a survey consisting of a total of 200 personally‐administered questionnaires was conducted at a selection of Hong Kong’s Mass Rapid Transport (MRT) stations in Hong Kong. The target sample included males and females aged 15 or over, with an equal distribution of each gender. The findings indicated that the majority of interviewees would like to use and reuse paper shopping bags rather than plastic shopping bags. In addition, the interviewees desired different attributes from paper shopping bags when compared with plastic shopping bags. Finally, the relationship between the duration of keeping a shopping bag and the frequency of reusing the same bag is identified.

Computers have transformed the design of everything from cars to coffee cups. Now the food industry faces the same revolution, with intelligent computer models being used in the design, production and marketing of food products. The combined market capitalisation of the world’s biggest food, cosmetics, tobacco, clothing and consumer electronics companies is $2 trillion, forming the world’s 500 richest companies. Many of these “fast‐moving consumer goods” companies now apply intelligent computer models to the design, production and marketing of their products. Manufacturers aim to develop and produce high volumes of these commodities with minimum costs, maximum consumer appeal, and of course, maximum profits. Products have limited lifetimes following the fashions of the consumer‐driven marketplace. With food and drink, little is known about many of the underlying characteristics and processes. Product development and marketing must therefore be rapid, flexible and use raw data alongside existing expert knowledge. Intelligent systems, such as neural networks, fuzzy logic and genetic algorithms, mimic human skills such as the ability to learn from incomplete information, to adapt to changing circumstances, to explain their decisions and to cope with novel situations. These systems are being used to tackle a growing range of problems, from credit card fraud detection and stock market prediction to medical diagnosis and weather forecasting. This paper introduces intelligent systems and highlights their use in all aspects of the food and drink industry, from ingredient selection, through product design and manufacture, to packaging design and marketing.

Silberline Ltd will be showing the extended range of Sparkle Silver non‐leafing aluminium pastes which are now available from production in Scotland, and used principally for automotive top coat paints. Examples of all grades will be on show, with particular emphasis on new products and new effects for two coat finishes.