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This article introduces a process chain for commercial aircraft wing multidisciplinary optimization (MDO) based on high fidelity simulation methods. The architecture of this process chain enables two of the most promising future technologies in commercial aircraft design in the context of MDO. These technologies are natural laminar flow (NLF) and aeroelastic tailoring using carbon fiber reinforced plastics (CFRP). With this new approach the application of MDO to an NLF forward swept composite wing will be possible.The main feature of the process chain is the hierarchical decomposition of the optimization problem into two levels. On the highest level the wing planform including twist and airfoil thickness distributions as well as the orthotropy direction of the composite structure will be optimized. The lower optimization level includes the wing box sizing for essential load cases considering the static aeroelastic deformations. Additionally, the airfoil shapes are transferred from a given NLF wing design and the natural laminar flow is considered by prescribing laminar-turbulent transition locations.

Majority of African countries have high stigma index(HSI) and are mostly populated by rural dwellers with high levels of illiteracy/ignorance. Therefore, poor education and knowledge of human immune deficiency virus(HIV) infection might be key drivers of stigmatization. Eight countries with a stigma index(STI) >40%(Niger, Guinea, Ghana, Sierra Leone, Liberia, Mali, Togo, and Democratic Republic of Congo) of 32 African countries with listed STI by UNAIDS, and three (Rwanda, Zambia, and Namibia), with a low stigma index (LSI) of 20%, were descriptively analyzed. Four knowledge classes(≤25%-class one;>25%≤50%-class two; >50%≤75% class three; >75%-class four), and categories of stigmatisation score (< 0.5-class one; 0.5< 1.0-class two; 1.0< 1.5-class three and >1.5-class four -signifying little, medium, high and very high tendency to stigmatize, respectively), were created based on respondents 'answers to twelve questions assessing knowledge of HIV, and four questions assessing stigmatisation of HIV-positive people, respectively. Data were characterized and evaluated by frequency tables using IBM SPSS Software. Respondents in knowledge classes three and four, mainly comprised urban dwellers in both LSI (98.0%urban vs 96.5%rural), and HSI (80.3%urban vs 64.5%rural) countries. Females had higher educational attainment than males in countries with LSI (98.35%females vs 97.6%males) than his (79.8% females vs 81.6% males). However, males expressed positive views (< 0.5-class one) about having an HIV-positive teacher, continuing to teach (i.e. least tendency for social stigmatization), and would buy vegetables from an HIV-positive vendor (i.e. least tendency for physical stigmatization), than females. Meanwhile, 48% of respondents would not buy vegetables from an infected vendor, yet they knew that HIV will not be transmitted by sharing food with an infected person. Impact factors of positive attitudes towards HIV are urbanization, educational attainment, and knowledge about HIV. LSI countries are distinguished from HSI countries by higher female educational attainment and knowledge about HIV than male, which may impact HIV stigmatization, and could be of socio-cultural significance. Lesser tendency to stigmatize among males than females may suggest that socio-cultural factors which enable stigmatization may be gender-related. The greater tendency towards physical than social stigmatization may reflect respondents' perception that physical contact enables HIV transmission. The contradiction between knowledge and belief was evident hence almost half of those who knew the mode of transmission of HIV, had a negative attitude towards an infected vendor.

This paper presents a structure design and optimization module, developed for the application inside multidisciplinary optimization process chains. The loads necessary for sizing and optimization are calculated in CFD or aeroelastic calculations and applied on a Finite Element Model that represents all primary structural elements of a wing. The FE model is created automatically from a parametric geometry description. The deformations and inner loads of the wingbox are calculated via linear static FE calculations; geometry and loads are provided to an external sizing tool. Each component has a set of design variables with discrete design points which are permutated to get the component's design candidates. A set of failure criteria is used to size the structure which can be made of composites or metal. The methodology is applied to the optimization of a forward swept composite for a short range aircraft and a design study comparing different stringer types and their influence on mass and structural deformation of the wing is performed.