Distributed learning of CNNs on heterogeneous CPU/GPU architectures

Convolutional Neural Networks (CNNs) have shown to be powerful classification tools in tasks that range from check reading to medical diagnosis, reaching close to human perception, and in some cases surpassing it. However, the problems to solve are becoming larger and more complex, which translates to larger CNNs, leading to longer training times that not even the adoption of Graphics Processing Units (GPUs) could keep up to. This problem is partially solved by using more processing units and distributed training methods that are offered by several frameworks dedicated to neural network training. However, these techniques do not take full advantage of the possible parallelization offered by CNNs and the cooperative use of heterogeneous devices with different processing capabilities, clock speeds, memory size, among others. This paper presents a new method for the parallel training of CNNs that can be considered as a particular instantiation of model parallelism, where only the convolutional layer is distributed. In fact, the convolutions processed during training (forward and backward propagation included) represent from $60$-$90$\% of global processing time. The paper analyzes the influence of network size, bandwidth, batch size, number of devices, including their processing capabilities, and other parameters. Results show that this technique is capable of diminishing the training time without affecting the classification performance for both CPUs and GPUs. For the CIFAR-10 dataset, using a CNN with two convolutional layers, and $500$ and $1500$ kernels, respectively, best speedups achieve $3.28\times$ using four CPUs and $2.45\times$ with three GPUs. Modern imaging datasets, larger and more complex than CIFAR-10 will certainly require more than $60$-$90$\% of processing time calculating convolutions, and speedups will tend to increase accordingly

The Chronotopic Imagination in Literature and Film

In this contribution, I would like to examine the way in which Bakhtin, in the two essays dedicated to the chronotope, lays the foundations for a theory of literary imagination. […] His concept of the chronotope may be interpreted as a contribution to a tradition in which Henri Bergson, William James, Charles Sander Peirce and Gilles Deleuze have been key figures. Like these four authors, Bakhtin is a philosopher in the school of pragmatism. His predilection for what Gary Saul Morson and Caryl Emerson have called “prosaics” puts him right at the heart of a philosophical family that calls forth multiplicity against metaphysical essentialism, and prefers the mundane to the universal. It seems wise to proceed carefully in the attempt to reconstruct Bakhtin’s theory of imagination. In this contribution to the debate, I choose to develop a philosophical dialogue between Bakhtin and the above-mentioned philosophical family. More specifically, it seems to me that the ideal point of departure for examining the way in which Bakhtin attempts to get to the bottom of the mysteries of literary imagination is Gilles Deleuze’s synthesis of Bergson’s epistemological view on knowledge as “the perception of images”, as well as Peirce’s theory of experience based on a typology of images. In the following, I show that Bakhtin’s view of the temporal-spatial constellations in literature demonstrates a strong affinity to the Bergsonian view that perception of the spatial world is colored by the lived time experienced by the observer. Based on this observation, I then develop a typology of images which places the concept of the chronotope in a more systematic framework

How conscious experience and working memory interact

Active components of classical working memory are conscious, but traditional theory does not account for this fact. Global Workspace theory suggests that consciousness is needed to recruit unconscious specialized networks that carry out detailed working memory functions. The IDA model provides a fine-grained analysis of this process, specifically of two classical workingmemory tasks, verbal rehearsal and the utilization of a visual image. In the process, new light is shed on the interactions between conscious and unconscious\ud aspects of working memory

Perceiving environmental structure from optical motion

Generally speaking, one of the most important sources of optical information about environmental structure is known to be the deforming optical patterns produced by the movements of the observer (pilot) or environmental objects. As an observer moves through a rigid environment, the projected optical patterns of environmental objects are systematically transformed according to their orientations and positions in 3D space relative to those of the observer. The detailed characteristics of these deforming optical patterns carry information about the 3D structure of the objects and about their locations and orientations relative to those of the observer. The specific geometrical properties of moving images that may constitute visually detected information about the shapes and locations of environmental objects is examined

Subjectivity in contemporary visualization of reality: re-visiting Ottoman miniatures

Though Ottoman miniatures are 2D representations, they carry the potential of conveying an individual’s perception in a more detailed manner as compared to 3D perspective renderings. In a typical 2-vanishing-point perspective; objects / subjects drawn in the foreground hide the ones that are located at their back: This phenomenon is called occlusion. In Ottoman miniatures there is no occlusion, all object / subject illustrations are wholistic, there is no partial description of figures. Consequently, you end up with a life form that is the synthesis of individual forms, a sui generis state... This unique visual narrative can be extended to cubist works where multifaceted descriptions are observed. Another advantage of Ottoman miniatures is that hierarchies of image and image maker are quite clear. Miniatures make use of distance, void, shape, scale relationships and their layout to give a sense of depth in space. Though objectivity is very much valued in visual representation, ideal objectivity is not possible since representations are created by subjects and subjects belong to cultures that have different criteria in forming / perceiving portrayals. Moreover, tools that are used for visual representations usually prove to be narrower than the scope of human perception. Departing from the point of view explained above, Muta-morphosis is a photography project that is created as an almost surreal visualization stemming from the real. The lack of a single perspectival structure due to multiplicity of perspectives after compressed panoramic imaging, can be linked to Ottoman miniatures, which in turn, connects the global contemporary representation to its local traditional counterpart. Keywords: Ottoman miniature painting, contemporary photography, child drawings, visualization, representation, reality, documentary, subjectivity, objectivity, visual narration

Beyond the aestheticization of modern ruins: the case of Incompiuto Siciliano

The modern Italian landscape includes a large number of public construction projects begun over the past 50 years but abandoned before completion—a testament to the misuse of public funds through political corruption and the influence of the Mafia. Since 2007, a group of artists named Alterazioni Video has been developing the project Incompiuto Siciliano, through which they have sought to counter the negative perception of these ruins by considering them as an aestheticized architectural style. The group’s approach is significant because visual arts, and especially photography, have in recent years been accused of pursuing a merely romanticizing objective that ignores the political, economic and social contexts in which modern ruins arise. Embedding the current paper within this discussion makes it possible to align Incompiuto Siciliano with literatures on contemporary archaeology that regard the aestheticization of ruins as a first step to a critical comprehension of the reasons behind their origination—which ultimately leads to their re-valorization and eventual re-activation