Effective Use of Dilated Convolutions for Segmenting Small Object Instances in Remote Sensing Imagery

Thanks to recent advances in CNNs, solid improvements have been made in semantic segmentation of high resolution remote sensing imagery. However, most of the previous works have not fully taken into account the specific difficulties that exist in remote sensing tasks. One of such difficulties is that objects are small and crowded in remote sensing imagery. To tackle with this challenging task we have proposed a novel architecture called local feature extraction (LFE) module attached on top of dilated front-end module. The LFE module is based on our findings that aggressively increasing dilation factors fails to aggregate local features due to sparsity of the kernel, and detrimental to small objects. The proposed LFE module solves this problem by aggregating local features with decreasing dilation factor. We tested our network on three remote sensing datasets and acquired remarkably good results for all datasets especially for small objects

PII S0361-9230(99)00144-6 Probing consciousness with an electrode

Voluntary behavior is unpredictable, unlike a reflex. Can we understand voluntary behavior in terms of neural processes, as we understand a reflex? The question was nothing but an intractable fantasy until Robert Wurtz and Michael Goldberg published a series of four papers in Journal of Neurophysiology in 1972 [3–6]. While studying single cell activities in the monkey superior colliculus in relation to visual and oculomotor functions, the authors discovered that cells ’ visual responses changed depending on the monkey’s subsequent behavior even though an identical stimulus was presented. Goldberg and Wurtz started off the second paper [4] by writing, “In all previous studies on visual receptive fields of single neurons...,the properties of the cells were studied without regard to the behavioral significance of the visual stimuli.... Theawake animal does not treat objects in the visual world uniformly: it responds to some and ignore

The Globus Pallidus Sends Reward-Related Signals to the Lateral Habenula

SummaryAs a major output station of the basal ganglia, the globus pallidus internal segment (GPi) projects to the thalamus and brainstem nuclei thereby controlling motor behavior. A less well known fact is that the GPi also projects to the lateral habenula (LHb) which is often associated with the limbic system. Using the monkey performing a saccade task with positionally biased reward outcomes, we found that antidromically identified LHb-projecting neurons were distributed mainly in the dorsal and ventral borders of the GPi and that their activity was strongly modulated by expected reward outcomes. A majority of them were excited by the no-reward-predicting target and inhibited by the reward-predicting target. These reward-dependent modulations were similar to those in LHb neurons but started earlier than those in LHb neurons. These results suggest that GPi may initiate reward-related signals through its effects on the LHb, which then influences the dopaminergic and serotonergic systems

Dopamine-Mediated Learning and Switching in Cortico-Striatal Circuit Explain Behavioral Changes in Reinforcement Learning

The basal ganglia are thought to play a crucial role in reinforcement learning. Central to the learning mechanism are dopamine (DA) D1 and D2 receptors located in the cortico-striatal synapses. However, it is still unclear how this DA-mediated synaptic plasticity is deployed and coordinated during reward-contingent behavioral changes. Here we propose a computational model of reinforcement learning that uses different thresholds of D1- and D2-mediated synaptic plasticity which are antagonized by DA-independent synaptic plasticity. A phasic increase in DA release caused by a larger-than-expected reward induces long-term potentiation (LTP) in the direct pathway, whereas a phasic decrease in DA release caused by a smaller-than-expected reward induces a cessation of long-term depression, leading to LTP in the indirect pathway. This learning mechanism can explain the robust behavioral adaptation observed in a location-reward-value-association task where the animal makes shorter latency saccades to reward locations. The changes in saccade latency become quicker as the monkey becomes more experienced. This behavior can be explained by a switching mechanism which activates the cortico-striatal circuit selectively. Our model also shows how D1- or D2-receptor blocking experiments affect selectively either reward or no-reward trials. The proposed mechanisms also explain the behavioral changes in Parkinson's disease

Analyzing Loose Contact Oxidation of Diesel Engine Soot and Ag/CeO2 Catalyst Using Nonlinear Regression Analysis

Loose contact (LC) oxidation kinetics of carbon black (CB) model soot and Ag/CeO2 catalyst was deduced from thermogravimetric analysis (TG) experiments. In the LC mode at ≧750 K, CB particles were likely to be combusted also by non-catalyzed oxidation, especially those particles located far from the catalyst surface, as well as Ag/CeO2-catalyed oxidation. Since the non-catalyzed oxidation is not due to catalytic activity, in order to deduce the catalytic activity from TG data, a nonlinear regression analysis method was proposed in this study to extract only the catalyzed oxidation part of the TG data. It was verified that this was successfully done with the equations used by the very good curve fits to the experimental TG data, and the catalytic activity was correctly obtained from LC samples with various degrees of physical contact between the CB and catalyst.

Dissociative photoionization of the NO molecule studied by photoelectron-photon coincidence technique

Low-energy photoelectron–vacuum ultraviolet (VUV) photon coincidences have been measured using synchrotron radiation excitation in the inner-valence region of the nitric oxide molecule. The capabilities of the coincidence set-up were demonstrated by detecting the 2s−1 → 2p−1 radiative transitions in coincidence with the 2s photoelectron emission in Ne. In NO, the observed coincidence events are attributed to dissociative photoionization with excitation, whereby photoelectron emission is followed by fragmentation of excited NO+ ions into O+ + N* or N+ + O* and VUV emission from an excited neutral fragment. The highest coincidence rate occurs with the opening of ionization channels which are due to correlation satellites of the 3σ photoionization. The decay time of VUV photon emission was also measured, implying that specific excited states of N atoms contribute significantly to observed VUV emission

22. Melting of polymer crystals below the melting point(poster presentation,Soft Matter as Structured Materials)

この論文は国立情報学研究所の電子図書館事業により電子化されました。高分子鎖は折りたたまれて結晶化することにより、非常に薄い板状単結晶として析出する。そこでGibbs-Thomson効果により、平衡融点以下の温度で融解する。この融解キネティクスに関して、通常の結晶融解の常識に反する非常に特殊な振る舞いを実験的に見いだした。この振る舞いは高分子性に由来するエントロピー障壁により矛盾なく説明できる

Artificial Rearing System for Praesagittifera naikaiensis (Acoela, Acoelomorpha) <Article>

Praesagittifera naikaiensis is an acoelomorph worm native to the seashore of the Seto Inland Sea. P. naikaiensis harbors a species of prasinophytes, Tetraselmis sp., as a symbiont. The symbiotic algae are acquired horizontally from the environment during the larval stage. In this study, we established a method for the rearing of adult P. naikaiensis as a first step toward using the animal in the study of development, evolution, and the symbiotic mechanism. We kept the animals in aquaria with closed seawater circulations. The bottom of the aquarium was half covered with sand collected from the seashore of the Seto Inland Sea. An LED light was suspended over the aquarium to aid photosynthesis. The system was maintained at a salinity of 32–33 ppt and a temperature of 14°C, on a 14-h light (35–80 μmol quanta m−2s−1)/10-h dark photoperiod. We succeeded in constantly producing sexually mature animals, independent of season. The system developed here will serve as a foundation for future studies on acoel evolution and development.本研究は科学研究費補助金(26924012)の助成を受けたものである