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Tandem wing aircrafts belong to an unconventional configurations group, and this type of design is characterised by a strong aerodynamic coupling, which results in lower induced drag. The purpose of this paper is to determine whether a certain trend in the wingspan impact on aircraft dynamic stability can be identified. The secondary goal was to compare the response to control of flaps placed on a front and rear wing.

The aerodynamic data and control derivatives were obtained from the computational fluid dynamics computations performed by the MGAERO software. The equations of aircraft longitudinal motion in a state space form were used. The equations were built based on the aerodynamic coefficients, stability and control derivatives. The analysis of the dynamic stability was done in the MATLAB by solving the eigenvalue problem. The response to control was computed by the step response method using MATLAB.

The results of this study showed that because of a strong aerodynamic coupling, a nonlinear relation between the wing size and aircraft dynamic stability proprieties was observed. In the case of the flap deflection, stronger oscillation was observed for the front flap.

Results of dynamic stability of aircraft in the tandem wing configuration can be found in the literature, but those studies show outcomes of a single configuration, while this paper presents a comprehensive investigation into the impact of wingspan on aircraft dynamic stability. The results reveal that because of a strong aerodynamic coupling, the relation between the span factor and dynamic stability is nonlinear. Also, it has been demonstrated that the configuration of two wings with the same span is not the optimal one from the aerodynamic point of view.

This paper presents first sight on the longitudinal control strategy for an aircraft in the tandem wing configuration. It is an aerodynamic strongly coupled configuration that needs a lot of detailed aerodynamic analysis which describes the mutual impact of the main parts of the aircraft. The purpose of this paper is to build the numerical model that allows to make an analysis of necessary flaps (front and rear) deflection and prepare the control strategy for this kind of aircraft.

Aircrafts’ aerodynamic characteristics were obtained using the MGAERO software which is a commercial computing fluid dynamics tool created by Analytical Methods, Inc. This software uses the Euler flow model. Results from this software were used in the static stability evaluation and trim condition analysis. The trim conditions are the outcome of the optimisation process whose goal was to find the best front and rear flap deflection to achieve the best lift to drag (L/D) ratio.

The main outcome of this investigation is the proposal of strategy for the front and rear flap deflection which ensured the maximum L/D ratio and satisfied the trim condition. Moreover, the analysis of the mutual impact of the front and rear wings and the analysis of the control surface impact on the aerodynamic characteristic of the aircraft are presented.

In terms of aerodynamic computation, MGAERO software uses an inviscid flow model. However, this research is for the conceptual stage of the design and the MGAERO software grantee satisfied accurate respect to relatively low time of computations.

The ultimate goal is to build an aircraft in a tandem wing configuration and to conduct flying tests or wind tunnel tests. The presented result is one of the milestones to achieve this goal.

The aircraft in the tandem wing configuration is an aerodynamic-coupled configuration that needs detailed analysis to find the mutual interaction between the front and rear wings. Moreover, the mutual impact of the front and rear flaps is necessary too. Obtaining these results allowed this study to build the numerical model of the aircraft in the tandem wing configuration. It allows to find the best strategy of flap deflection, which allows to obtain the maximum L/D ratio and satisfy the trim condition.

This paper aims to challenge the assumption that brands of everyday products have only used lifestyle marketing in the past 30 years by conducting the first case study of the marketing practices of the Swedish toothpaste brand Stomatol (1910–1940). Through visual social semiotic analysis, it explores how the brand was a pioneer in lifestyle marketing, using discourses of modernity, beauty and the Swedish “way of life” to sell its toothpaste.

Two hundred Stomatol advertisements were collected from the Swedish Historical Newspaper Archive and analysed using visual social semiotics. The analysis considers how the idea of a cultural Swedishness centred around modernity and beauty developed between 1910 and 1940, and how both linguistic and semiotic resources were used to make these claims seem credible.

At a time when its main adversaries were capitalising upon science in their advertisements to construct authority and credibility, Stomatol instead targeted lifestyle. Modernity, beauty and the Swedish “way of life” were central themes of their marketing campaigns, yet the way these themes were articulated varied between 1910 and 1940 in accordance with changing popular discourse. This made Stomatol more competitive than other toothpaste brands because it was able to sell an experience rather than a product, turning it into Sweden’s most popular toothpaste.

This paper demonstrates the importance of case studies to challenge the assumption that toothpaste brands have only used lifestyle marketing in the past 30 years (a claim based on Anglocentrism). It also showcases the need to further investigate non-Anglo countries when conducting research into lifestyle marketing to build a more nuanced perspective on its origins and the supposed novelty of (largely) US practices. Thus, Stomatol makes an important case for Sweden as a trailblazer in lifestyle marketing.

Groundwater resources are the primary source of meeting the water demand in Bangladesh. In rural areas, hand-pumped tube wells have been the primary source of drinking water. Though studies claim that Bangladesh has the potential to achieve universal safe drinking water supply coverage, the presence of excessive arsenic in the shallow groundwater sources, and the encroachment of salinity in the coastal aquifers in coastal regions (Satkhira, Khulna, Bagerhat, Patuakhali, Jhalakathi, Pirojpur, Barisal, Barguna etc.) hind the path. The concerned authorities of government and other non-government organizations assist the coastal people with alternative technologies like Desalination Plant, Arsenic-Iron Removal Plant, Pond Sand Filtration (PSF), Managed Aquifer Recharge, Rainwater Harvesting System, Installation of Shallow, and Deep Tube Wells. But based on case studies and surveys, this article shows how these existing technologies fail to ensure water safety within the coastal areas. The Singaporean water management policy is an example, this article advocates for necessary government intervention to ensure safe drinking water in coastal areas.

To date, there are no studies in the literature that provide a comprehensive understanding of the interrelationships between the slenderness ratio and the main design criteria in supertall towers (=300 m). In this paper, this important issue was explored using detailed data collected from 75 cases.

This paper was carried out with a comprehensive literature review including the database of the Council on Tall Buildings and Urban Habitat(CTBUH) (CTBUH, 2022), peer-reviewed journals, MSc theses and PhD dissertations, conference proceedings, fact sheets, architectural and structural magazines and other Internet sources. In this study, the case study method was also used to gather and consolidate information about supertall towers to analyze the interrelationships. Cases were 75 supertall buildings in various countries [44 from Asia (37 from China), 16 from the Middle East (6 from Dubai, the United Arab Emirates), 11 from the United States of America and 3 from Russia, 1 from the UK].

The paper's findings highlighted as follows: (1) for buildings in the height range of 300–399 m, the slenderness ratio was usually between 7 and 7.9 and megatall towers were frequently built at a slenderness ratio of 10–15; (2) the median slenderness ratio of buildings in the 400–599 m height ranges was around 8.6; (3) a trend towards supertall slender buildings (=8) was observed in Asia, the Middle East and North America; (4) residential, office and mixed-use towers had a median slenderness ratio of over 7.5; (5) all building forms were utilized in the construction of slender towers (>8); (6) the medium slenderness ratio was around 8 for supertall buildings constructed with outriggered frame and tube systems; (7) especially concrete towers reached values pushing the limits of slenderness (>10) and (8) since the number of some supertall building groups (e.g. steel towers) was not sufficient, establishing a scientific relationship between aspect ratio and related design criteria was not possible.

To date, there are no studies in the literature that provide a comprehensive understanding of the interrelationships between the slenderness ratio and the main design criteria in supertall towers (=300 m). This important issue was explored using detailed data collected from 75 cases.

In this paper, we examine the comparative advantage of Korea and China while focusing on their technology level. The three digit SITC (Standard International Trade Classification) data is classified by technology level and the revealed comparative advantage (RCA) is derived from 1992-2009 by using UN COMTRADE data. For careful interpretation of the comparative advantage and technology levels, we also examined intra-industry trade and unit values of bilateral Korea-China trade, and semi-conductor industry technology. We found that the revealed comparative advantage has moved from low technology products to high technology products in Korea. China still maintains a comparative advantage in low technology products such as textiles and clothing, but at the same time, China’s high and medium-high technology products have recently gained a comparative advantage. The perception that China only has a comparative advantage for labor intensive products with low technology should be changed based on our analysis. However, China’s advancement in technology should not be overestimated. When comparing the unit value of basic materials of Korea’s and China’s exports, we found that Korea’s export product prices are on average higher than that of China’s, although the gap is reducing. A wider technology gap between Korea and China still exists in the semi-conductor industry, which is one of the most advanced high technology industries throughout the world.

This paper aims to use the advertisements of three major brands – Chymol, Formamint and Lifebuoy Soap – to examine how advertisers responded to the 1918–1919 influenza pandemic in Great Britain influenza pandemic. It looks particularly at the ways in which marketing strategies changed and how these strategies were enacted in the lexical and semiotic choices (e.g. language, image, colour, typography, texture, materiality, composition and layout) of advertisements.

A total of 120 advertisements for the three brands were collected from the British Newspaper Archive and analysed using the theory and analytical tools of multimodal critical discourse analysis. The general themes and semiotic structures of the advertisements were identified, with the aim of deconstructing the meaning potentials of verbal and visual resources used to convey ideas about the pandemic, and how they work to shape public understanding of the products and make them appear as effective and credible.

Each brand rapidly changed their marketing strategy in response to the influenza pandemic, using such techniques as testimonials, hyperbole, scaremongering and pseudoscientific claims to persuade consumers that their products offered protection. Whilst these strategies may appear manipulative, they also had the function of fostering reassurance and sympathy amongst the general public in a moment of turmoil, indicating the important role of brands in building consumer trust and promoting a sense of authority in early twentieth-century Britain.

Exploring the way in which advertisers responded to the 1918‐1919 influenza pandemic reminds us of the challenges of distinguishing legitimate and illegitimate medical advice in a fast-moving pandemic and highlights the need to cast a critical eye to the public health information, particularly when it comes from unofficial sources with vested interests.

This paper aims to historicise the contemporary chlorophyll trend through the first academic study of its early marketing in Sweden (1950–1953). Using multimodal critical discourse analysis, it demonstrates how brands used advertisements to convince female consumers of chlorophyll’s necessity to fulfil certain aspirational goals.

In all, 150 advertisements for chlorophyll products were collected from the Swedish Historical Newspaper Archive, as well as 600 additional advertisements for the three most popular products (toothpaste/mouthwash, sanitary towels and soap) from 1940 to 1950 and from 1954 to 1964. Then, multimodal critical discourse analysis was used to investigate how the products were marketed before, during and after the chlorophyll trend, identifying the general themes and linguistic/semiotic structures of the advertisements.

This paper shows how the commercial use of chlorophyll offered a lucrative opportunity for marketers, acting as a “tabula rasa” on which they could use discourses of science, nature, idealised femininity and luxury to draw connections with health, modernity and beauty, despite the product having no real purpose or value.

Viewing this fad from a historical perspective emphasises how brands, marketers and influencers continue to capitalise on the anxieties of female consumers with promises around beauty, hygiene and health. It, thus, offers us critical distance to reflect on contemporary claims about chlorophyll’s health benefits to make informed choices.

The small-scale artisanal fishers in coastal Bangladesh are comparatively more vulnerable to climate risks than any other communities in Bangladesh. Based on practicality, this paper aims to explain the local level climate change perception, its impact and adaptation strategies of the fisher in southeast coastal villages in Bangladesh.

To achieve the above objective, this study used structural, semi-structured interviews and focus group discussion in two coastal communities, namely, at Salimpur in the Sitakund coast and Sarikait Sandwip Island, Bangladesh. It reviews and applies secondary data sources to compare and contrast the findings presented in this study.

Results show that the fishers perceived an increase in temperature, frequency of tropical cyclones and an increase in sea level. They also perceived a decrease in monsoon rainfall. Such changes impact the decreasing amount of fish in the Bay of Bengal and the fishers’ livelihood options. Analysing seasonal calendar of fishing, findings suggest that fishers’ well-being is highly associated with the amount of fish yield, rather than climatic stress, certain non-climatic factors (such as the governmental rules, less profit, bank erosion and commercial fishing) also affected their livelihood. The major adaptation strategies undertaken include, but are not limited to, installation of tube well or rainwater harvesting plant for safe drinking water, raising plinth of the house to cope with inundation and use of solar panel/biogas for electricity.

Despite experiencing social stress and extreme climatic events and disasters, the majority of the fishing community expressed that they would not change their profession in future. The research suggests implementing risk reduction strategies in the coastal region of Bangladesh that supports the small-scale fishers to sustain their livelihood despite climate change consequences.