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This paper aims to automatically derive a 2D parametric model of the main characteristic lines of a car from images, blueprints or hand-made sketches of its side view. Then this model can be used for the further computer-aided design manipulation starting from images of the side view of a car.

The method combines different image edge detection techniques and edge removal processes with optimization techniques according to local and global constraints specific of the single curves to automatically construct a precise parametric model of the main character lines of a car from images. First, process the car image to compute the most important curves and then warp a car template model to match its feature points and curves with the ones detected in the image.

The paper provides method to construct parametric model from an image using maximum cover ratio to the edge points obtained by state-of-the-art edge detection algorithms. A feature points’ organization mechanism produces quadric curves to express feature curves of a product.

The robustness of the presented method depends on the completeness of edge detection results and the accuracy of some key points’ registration result, so if the image is not good, the result cannot be trusted. Only side-view is considered in this paper. Additional limits in the process regard the side view verification: pictures of the front or rear view can be wrongly classified as lateral ones when they contain round lights.

This program enables designers to convert the image to geometric parametric model directly.

The method is applicable to shaded pictures, sketches and blue prints of the side view of a car. It can process a database of car images in a batch mode or a specific picture on user demand. The method classifies the cars to different categories: SUV/Wagon/Hatchback, sedan, city and coupe. The authors obtain good results for every category.

The purpose of this paper is to set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions. An instance of filleting operator is prototyped under this framework and presented in the paper.

In this paper, a generic mesh modification operator has been designed and a new instance of this operator for filleting finite element (FE) sharp edges of tetrahedral multi-partitioned meshes is also pro-posed. The filleting operator works in two main steps. The outer skin of the tetrahedral mesh is first deformed to round user-specified sharp edges while satisfying constraints relative to the shape of the so-called Virtual Group Boundaries. Then, in the filleting area, the positions of the inner nodes are relaxed to improve the aspect ratio of the mesh elements.

The classical mainstream methodology for product behaviour optimization involves the repetition of four steps: CAD modelling, meshing of CAD models, enrichment of models with FE simulation semantics and FEA. This paper highlights how this methodology could be simplified by two steps: simulation model modification and FEA. The authors set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions and the corresponding fillet operator is devised.

The proposed framework shows only a paradigm of direct modifications of semantic enriched meshes. It could be further more improved by adding or changing the modules inside. The fillet operator does not take into account the exact radius imposed by user. With this proposed fillet operator the mesh element density may not be enough high to obtain wished smoothness.

This paper fulfils an identified industry need to speed up the product behaviour analysis process by directly modifying the simulation semantic enriched meshes.

The purpose of this paper is to focus on the characterization and classification of parts with respect to the meshing issue, and notably the meshing of thin parts difficulty handled automatically and which often requires adaptation steps. The objective is to distinguish the so-called thin parts and parts with thin features from the other parts.

The concepts of thin part and part with thin features are introduced together with the mechanisms and criteria used for their identification in a CAD models database. The criteria are built on top of a set of shape descriptors and notably the distance distribution which is used to characterize the thickness of the object. To speed up the identification process, shape descriptors are computed from tessellated parts.

A complete modular approach has been designed. It computes shape descriptors over parts stored in a directory and it uses criteria to distinguish three categories: thin parts, parts with thin features and other parts. Being the three categories identified, the user can spend more time on the parts that are considered as more difficulty meshable.

The approach is limited to the three above mentioned categories. However, it has been designed so that the values corresponding to the shape descriptors and associated meshing qualities can easily be inserted within a machining learning tool later on.

The use of the developed tool can be seen as a pre-processing step during the preparation of finite element (FE) simulation models. It is automatic and can be run in batch and in parallel.

The approach is modular, it is simple and easy to implement. Categories are built on top of several shape descriptors and not on a unique signature. It is independent of the CAD modeler. This approach is integrated within a FE simulation model preparation framework and help engineers anticipating difficulties when meshing CAD models.

This paper describes the different ways in which people in the highlands of Papua New Guinea are talking about climate change. It demonstrates that people locate themselves in this process of change in terms of food production and exchange, and that some of the changes being witnessed are also related to the impacts of a growing cash economy on social relations.

This ethnography involved 12 months fieldwork including participant observation and interviews.

This is a qualitative study that recognises the perspective of local people for understanding culturally mediated experiences of climate change. However, data regarding rainfall and temperatures over time would be a useful addition for thinking about the extent to which the climate has in fact changed in recent years.

The implications of this paper are that the predictions made in 1990 about increases in production as a result of climate change are apparently coming true, with benefits for some food and coffee producers. But that there are complex social processes occurring at the same time as climate change that mean people’s ability to adapt is dependent on other social conditions. Maintaining ecologically sustainable methods of production and local cultural practices may enable more resilience to the impacts of climate change.

The experiences of people living in the Eastern Highlands and the ways in which people use the discourse of climate change are yet to be acknowledged in policy circles or socio-cultural anthropology literature. This paper presents a partial account of how people in Papua New Guinea are experiencing and talking about change.

The purpose of this paper is to reflect on the impact of globalisation and productive restructuring in contemporary migration flows in Latin America. It analyses two different movements to/from Latin America: Bolivians in São Paulo and Brazilians in London, seeking to highlight the precarious work conditions of migrants from the region.

The paper uses two interrelated research projects. One focuses on Bolivian workers in São Paulo. It used reference documents, and files from the local press and academic articles to map work dynamics of Bolivian migrants working in sweatshops. The other was conducted in London, where in‐depth interviews and participant observations were conducted with Brazilians working in low‐skilled jobs, to explore motives behind migration and settlement.

There is increasing mobility between different countries that receive immigrants with flexible proposals about constructing “new life projects”. These migrants seek to escape unfavourable living and working conditions, yet an overall perspective of flexible capitalism in its forms of production, distribution and consumption is observable. Both contexts feature precarious employment relationships, with informality, illegality and ethnic social networks being the main elements of attraction and support in host countries. Differences are located in the perspectives of return and settlement, given the different economic situations in England, Brazil and Bolivia.

Sample size does not allow making representative statements or generalisations about Brazilians in London. In addition, it was not possible to get primary data from Bolivians in São Paulo because the clandestine nature of the sweatshops makes it difficult to gain access, and to obtain reliable data.

The paper offers an important departure point to advance discussions about productive restructuring, informality, and Latin American mobilities by addressing the intersections between employment relations, migration and geographical mobility within/from Latin America.

Constrained input use and lower productivity of rural establishments may be associated with restricted or concentrated access to financial resources, especially in developing countries. Meanwhile, agricultural activity entails risks associated with the volatility of net cash flows and external events, which may discourage riskier but higher return investments (e.g. technology). As rural credit can alleviate the former, and rural insurance may help alleviate the latter, the combination of both policies might endorse each other. The purpose of this study is to analyze the use of rural credit and rural insurance policies with respect to productivity and crop area, in São Paulo state, Brazil, using farmer's microdata from two surveys realized in 2007/08 and 2016/17.

This study uses propensity score matching and the entropy balance approaches in a complementary way. This study compared three policy treatments – rural credit, rural insurance and both policies combined, against establishments that received neither one. The analysis considered sugarcane, grain and grape crops separately and employed farmer's microdata. Moreover, the analysis was stratified into two categories: establishments owned by family farmers and those that did not.

Rural credit policy is related to higher productivity and larger cultivated area for grains and only to larger area for grape crops in the last analyzed period (2016/17). Rural insurance, as a unique policy or combined with credit, is related to higher productivity and cultivated areas, for all analyzed crops, only in the second period (2016/17), as the policy became more accessible to farmers. Heterogeneity regarding crops and farmers might influence the effectiveness of these policies. Despite rural insurance being related to a better performance regarding the outcome variables, it still reaches a small share of farmers, especially when combined with credit.

Many studies about the effectiveness of rural credit in Brazil have been conducted throughout the years, while there have been fewer studies regarding rural insurance since it became an important policy in the mid-2000s. However, few studies have conducted an analysis comparing its individual and interactive influences, with such level of disaggregation, on a farm-level database, considering the heterogeneity of the data and the different categories of farmers.