Context-Aware Single-Shot Detector

SSD is one of the state-of-the-art object detection algorithms, and it combines high detection accuracy with real-time speed. However, it is widely recognized that SSD is less accurate in detecting small objects compared to large objects, because it ignores the context from outside the proposal boxes. In this paper, we present CSSD--a shorthand for context-aware single-shot multibox object detector. CSSD is built on top of SSD, with additional layers modeling multi-scale contexts. We describe two variants of CSSD, which differ in their context layers, using dilated convolution layers (DiCSSD) and deconvolution layers (DeCSSD) respectively. The experimental results show that the multi-scale context modeling significantly improves the detection accuracy. In addition, we study the relationship between effective receptive fields (ERFs) and the theoretical receptive fields (TRFs), particularly on a VGGNet. The empirical results further strengthen our conclusion that SSD coupled with context layers achieves better detection results especially for small objects ($+3.2\% {\rm AP}_{@0.5}$ on MS-COCO compared to the newest SSD), while maintaining comparable runtime performance

Design and Implementation of a FPGA and DSP Based MIMO Radar Imaging System

The work presented in this paper is aimed at the implementation of a real-time multiple-input multiple-output (MIMO) imaging radar used for area surveillance. In this radar, the equivalent virtual array method and time-division technique are applied to make 16 virtual elements synthesized from the MIMO antenna array. The chirp signal generater is based on a combination of direct digital synthesizer (DDS) and phase locked loop (PLL). A signal conditioning circuit is used to deal with the coupling effect within the array. The signal processing platform is based on an efficient field programmable gates array (FPGA) and digital signal processor (DSP) pipeline where a robust beamforming imaging algorithm is running on. The radar system was evaluated through a real field experiment. Imaging capability and real-time performance shown in the results demonstrate the practical feasibility of the implementation

Influence of Road Connectivity and Public Transport Accessibility on Subjective Wellbeing during Travel: An Explanation from Travel Mode: Evidence from five Communities around Subway Stations in Harbin

Existing studies have shown that increased subjective wellbeing comes with individual and societal benefits. Now citizens spend a significant amount of time per day on trips. Whether the change of transport environment factors, especially the construction of subway station can effectively improve residents' subjective wellbeing during travel or not is now concerned more than before when creating a “Real Emotional City”. This study aims to explore the relationship between road connectivity, public transport accessibility around subway stations and residents' subjective wellbeing during travel, and the mediating effect of travel modes. Data form 400 residents were collected from communities in Harbin which included travel modes, subjective wellbeing during travel and basic individual information. It turns out that the cognitive judgments and the emotional feelings (two aspects of travel wellbeing) need to be discussed separately because they are almost independently affected. Although cycling and walking are active, only pedestrians reported higher travel satisfaction when controlling travel time and other confounding factors. We found that for each additional unit of road network density, the number of people travelling by public transport will increase. Residents with better bus station accessibility and who have better road connectivity are likely to have higher travel satisfaction. Pleasant travel mood is not related to bus accessibility, and had a weak relationship with distance to subway station. In addition, residents closer to subway stations have higher levels of satisfaction and positive mood, but the results of subway travelers prove that this does not come from their cognitive judgments during travel, which indicates that some other factors may be more important. The findings highlight the heterogeneity of relationships between travel mode, transport environment factors and subjective wellbeing and have implications for intervention strategies and policies designed to promote travel environmental and behaviour chang

Comparative proteomic profiling reveals molecular characteristics associated with oogenesis and oocyte maturation during ovarian development of Bactrocera dorsalis (Hendel)

Time-dependent expression of proteins in ovary is important to understand oogenesis in insects. Here, we profiled the proteomes of developing ovaries from Bactrocera dorsalis (Hendel) to obtain information about ovarian development with particular emphasis on differentially expressed proteins (DEPs) involved in oogenesis. A total of 4838 proteins were identified with an average peptide number of 8.15 and sequence coverage of 20.79%. Quantitative proteomic analysis showed that a total of 612 and 196 proteins were differentially expressed in developing and mature ovaries, respectively. Furthermore, 153, 196 and 59 potential target proteins were highly expressed in early, vitellogenic and mature ovaries and most tested DEPs had the similar trends consistent with the respective transcriptional profiles. These proteins were abundantly expressed in pre-vitellogenic and vitellogenic stages, including tropomyosin, vitellogenin, eukaryotic translation initiation factor, heat shock protein, importin protein, vitelline membrane protein, and chorion protein. Several hormone and signal pathway related proteins were also identified during ovarian development including piRNA, notch, insulin, juvenile, and ecdysone hormone signal pathways. This is the first report of a global ovary proteome of a tephritid fruit fly, and may contribute to understanding the complicate processes of ovarian development and exploring the potentially novel pest control targets