Rethinking Object Detection in Retail Stores

The convention standard for object detection uses a bounding box to represent each individual object instance. However, it is not practical in the industry-relevant applications in the context of warehouses due to severe occlusions among groups of instances of the same categories. In this paper, we propose a new task, ie, simultaneously object localization and counting, abbreviated as Locount, which requires algorithms to localize groups of objects of interest with the number of instances. However, there does not exist a dataset or benchmark designed for such a task. To this end, we collect a large-scale object localization and counting dataset with rich annotations in retail stores, which consists of 50,394 images with more than 1.9 million object instances in 140 categories. Together with this dataset, we provide a new evaluation protocol and divide the training and testing subsets to fairly evaluate the performance of algorithms for Locount, developing a new benchmark for the Locount task. Moreover, we present a cascaded localization and counting network as a strong baseline, which gradually classifies and regresses the bounding boxes of objects with the predicted numbers of instances enclosed in the bounding boxes, trained in an end-to-end manner. Extensive experiments are conducted on the proposed dataset to demonstrate its significance and the analysis discussions on failure cases are provided to indicate future directions. Dataset is available at https://isrc.iscas.ac.cn/gitlab/research/locount-dataset.Comment: Information Erro

Bis{μ-2,2′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolato}dinickel(II)

The asymmetric unit of the title compound, [Ni2(C16H14N2O2)2], contains an NiII cation which is coordinated by two imine N atoms and by two phenolate O atoms of the salen ligand {salen = N,N′-bis­(salicyl­idene)ethane-1,2-diamine or 2,2′-[ethane-1,2-diyl­bis(nitrilo­methyl­idyne)]diphenol}, leading to a distorted square-planar conformation. When a secondary Ni—O inter­action > 2.41 Å to the neighbouring phenolate O atom is considered, two mol­ecules are linked into a centrosymmetric dimer with an overall square-pyramidal coordination for the NiII cation. Weak π–π inter­actions with a shortest interplanar distance of 3.704 Å help to stabilize the crystal structure

A Novel Wireless Localization Fusion Algorithm: BP-LS-RSSI

With the increasing demand for location-aware services, high-precision indoor positioning play more important role for some applications. People also put forward higher requirements on positioning accuracy. BP neural network as a kind of typical forward neural network has the very strong self learning ability and can approximate any discontinuity of rational function. This paper proposes BP-LS-RSSI localization model, then use the model to fix received signal strength indication (RSSI) values for positioning by the LS algorithm. Since the positioning accuracy do not satisfy the needs by the traditional LS algorithm, we transfer the RSSI values into confidence weights according to the topology of network, then use the weighted least squares (LS) method to further optimize the positioning system. Simulation results show that the proposed algorithm has obvious increase to the positioning accuracy is a feasible localization algorithm

Mixed Boundary-Value Analysis of Rocking Vibrations of an Elastic Strip Foundation on Elastic Soil with Saturated Substrata

The dynamic response of an elastic strip foundation lying on elastic soil with saturated substrata is greatly affected by pore pressure induced by a rocking moment. In this paper, we explore the mixed boundary-value problem of the rocking vibration of an elastic strip foundation on elastic soil with saturated substrata via Biot dynamic equations. First, the wave equations concerning both the single-phase elastic layer and the saturated half-space are solved using a Fourier integral transform technique. The dual integral equations of the rocking vibration of an elastic strip foundation are established according to the mixed boundary conditions. Finally, the relationship of the dynamic compliance coefficient with the dimensionless frequency is obtained by applying Simpson’s rule to conduct numerical calculation. We also analyse the influences of the elastic layer’s thickness and elastic characteristic parameters of the foundation on the rocking vibration

Observation of simultaneously low CO, NOx and SO2 emission during oxy-coal combustion in a pressurized fluidized bed

Pressurized oxy-fuel combustion is a promising technology for CO2 capture with respect to its high combustion efficiency and the simultaneous reduction of gaseous pollutants. A 10 kWth bubbling fluidized bed reactor with continuous coal-feeding was designed, and effects of pressure, temperature and fuel types on pollutant emission were investigated in detail. Generally, the relatively low carbon content in the ash and CO concentration in the flue gas demonstrated that the combustion efficiency was improved by high pressure. The concentration of NO, N2O and SO2 showed decreasing trends with the increase of pressure. Moreover, the effect of pressure on the emission of NO and SO2 in the lower pressure (≤0.3 MPa) was more pronounced than that in the higher pressure. The concentrations of NO and SO2 correlated positively with temperature, while for N2O, it had a negative correlation. Compared with air combustion, NO and SO2 emission dropped sharply in 21%O2/79%CO2 atmosphere. However, N2O concentration during oxy-combustion was slightly higher than that in air combustion in the range of experimental pressure

Effect of sand on the vacuum consolidation of dredged slurry

Vacuum preloading is often used to improve the geotechnical properties of dredged slurry. Although the performance of this method has improved with rapidly developing technology, soil columns usually formed on the drainage boundary induce the decrease of permeability around the boundary, thereby limiting the further development of this method. To address this issue, this paper proposes a method for pretreating the slurry combined with sand prior to vacuum consolidation. This method partially replaces the fine particles with sand to reduce the formation of soil columns. Two groups of vacuum preloading tests were performed to investigate the effect of sand content and sand grain size on the vacuum consolidation of dredged slurry. The test results revealed that for a given sand grain size, increasing the sand content of the sand-slurry mixture increased the pore water drainage and accelerated the dissipation of pore water pressure, thereby increasing the vane shear strength. In contrast, for a constant sand content, the samples containing coarse sand exhibited increased pore water drainage and accelerated dissipation of pore water pressure, thereby increasing the vane shear strength of the soil