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Significance: Researchers have made great progress in single-image super-resolution (SISR) using deep convolutional neural networks. However, in the field of leukocyte imaging, the performance of existing SISR methods is still limited as it fails to thoroughly explore the geometry and structural consistency of leukocytes. The inaccurate super-resolution (SR) results will hinder the pathological study of leukocytes, since the structure and cell lineage determine the types of leukocyte and will significantly affect the subsequent inspection. Aim: We propose a deep network that takes full use of the geometry prior and structural consistency of the leukocyte images. We establish and annotate a leukocyte dataset, which contains five main types of leukocytes (basophil, eosinophil, monocyte, lymphocyte, and neutrophil), for learning the structure and geometry information. Approach: Our model is composed of two modules: prior network and SR network. The prior network estimates the parsing map of the low-resolution (LR) image, and then the SR network takes both the estimated parsing map and LR image as input to predict the final high-resolution image. Result: Experiments show that the geometry prior and structural consistency in use obviously improves the SR performance of leukocyte images, enhancing the peak-signal-to-noise ratio (PSNR) by about 0.4 dB in our benchmark. Conclusion: As proved by our leukocyte SR benchmark, the proposed method significantly outperforms state-of-the-art SR methods. Our method not only improves the PSNR and structural similarity indices, but also accurately preserves the structural details of leukocytes. The proposed method is believed to have potential use in the wide-field cell prescreening by simply using a low-power objective.

We present a technique for simulating plastic deformation in sheets of thin materials, such as crumpled paper, dented metal, and wrinkled cloth. Our simulation uses a framework of adaptive mesh refinement to dynamically align mesh edges with folds and creases. This framework allows efficient modeling of sharp features and avoids bend locking that would be otherwise caused by stiff in-plane behavior. By using an explicit plastic embedding space we prevent remeshing from causing shape diffusion. We include several examples demonstrating that the resulting method realistically simulates the behavior of thin sheets as they fold and crumple. Copyright © ACM 2013.

Dissertação de mestrado integrado em Engenharia Mecânica, Este trabalho consiste na otimização e desenvolvimento de uma ferramenta de corte, utilizada para a perfuração de folhas de papel destinadas a serem encadernadas. Neste trabalho é apresentado um estudo onde é analisado o mercado das máquinas de encadernação, os seus sistemas de perfuração e as ferramentas utilizadas para perfurar o papel. As características do papel e o seu comportamento quando puncionado na direção da sua espessura tem uma elevada importância no ramo da encadernação e por essa mesma razão esse assunto também é mencionado neste trabalho. Com isto pretende-se adquirir o conhecimento necessário acerca deste tipo de ferramenta de modo a que seja possível obter uma ferramenta de corte capaz de perfurar um número mais elevado de folhas de papel ao mesmo tempo ou reduzir a força necessária ao corte de uma resma de papel. Além disto, foi projetada uma banca de ensaios para poder testar diferentes ferramentas para perfurar papel, com o objetivo de obter os valores da força de corte para que a furação do papel aconteça e para se conseguir criar e manter uma plataforma de testes ativa para que este tipo de ferramentas possam ser testadas. Estes ensaios serão importantes para obter os valores da força de corte e também para testar as ferramentas com as novas geometrias de ferramenta. Em seguida, com o objetivo de melhorar uma ferramenta de corte, foram estudadas todas as características de uma ferramenta e utilizando uma ferramenta existente no mercado como ponto de partida, foram implementadas as melhorias alcançadas. Posteriormente foi utilizado o software Ansys para comparar a força de corte necessária à perfuração de uma folha, da nova ferramenta. E utilizando a banca de ensaios a nova ferramenta será testada a perfurar diferentes tamanhos de resmas de papel e devidamente comparada com as antigas geometrias existentes., This dissertation resides on the optimization and development of a cutting tool used for punching sheets of paper intended to be bound. This paper presents a study where the market of binding machines is analyzed, its paper punching system, as well as the instrument used to puncture the paper. The paper’s characteristics and its performance when puncturing in the thickness direction, has a high importance in the binding industry and therefore is also mentioned in this dissertation. The aim is to acquire the necessary knowledge about this kind of puncher in order to obtain a cutting tool capable of punching a higher number of sheets of paper or reduce the strength required to punch a ream of paper. In addition, a test platform was designed to be able to test different instruments, in order to obtain data results of cutting strength of the punching of the paper and also to be able to create and maintain an active test platform, so such tools can be tested. These tests were important to obtain results of the cutting strength and also to test the new geometries of the punchers. Then, in order to improve a puncher, all puncher characteristics were studied and by using an existing tool of the market as a starting point, new improvements were implemented. Subsequently, ANSYS software was used to compare the necessary data to punch a sheet from the new puncher. And using the test platform, the new puncher was tested by punching different sizes of reams of paper and properly compared with the old existing punchers.

We study the static and dynamic properties of networks of crumpled creases formed in hand crushed sheets of paper. The fractal dimensionalities of crumpling networks in the unfolded (flat) and folded configurations are determined. Some other noteworthy features of crumpling networks are established. The physical implications of these findings are discussed. Specifically, we state that self-avoiding interactions introduce a characteristic length scale of sheet crumpling. A framework to model the crumpling phenomena is suggested. Mechanics of sheet crushing under external confinement is developed. The effect of compaction geometry on the crushing mechanics is revealed.

Designing computer systems for educational purpose is a difficult task. While many of them have been developed in the past, their use in classrooms is still scarce. We make the hypothesis that this is because those systems take into account the needs of individuals and groups, but ignore the requirements inherent in their use in a classroom. In this work, we present a computer system based on a paper and tangible interface that can be used at all three levels of interaction: individual, group, and classroom. We describe the current state of the interface design and why it is appropriate for classroom orchestration, both theoretically and through two examples for teaching geometry.

We have devised a paper model of the auricle that is simple to design and easily fabricated. An oval-shaped sheet of paper is folded so that the prominent and hollow parts center around a helical crus and concha. Most parts of the human auricle can be created by using this model. Studies of the model show that a large skin area is required for the helical crus. The model is considered to be useful in simulating total or partial auricular reconstruction. It also reveals new possibilities in reconstructive methods using tissues composed of cartilage and skin, which are flat and large. Furthermore, it is interesting that the formation of our paper model by forward rotation and folding is compatible with the process of auricle embryonic development.