FoveaBox: Beyond Anchor-based Object Detector

We present FoveaBox, an accurate, flexible, and completely anchor-free framework for object detection. While almost all state-of-the-art object detectors utilize predefined anchors to enumerate possible locations, scales and aspect ratios for the search of the objects, their performance and generalization ability are also limited to the design of anchors. Instead, FoveaBox directly learns the object existing possibility and the bounding box coordinates without anchor reference. This is achieved by: (a) predicting category-sensitive semantic maps for the object existing possibility, and (b) producing category-agnostic bounding box for each position that potentially contains an object. The scales of target boxes are naturally associated with feature pyramid representations. In FoveaBox, an instance is assigned to adjacent feature levels to make the model more accurate.We demonstrate its effectiveness on standard benchmarks and report extensive experimental analysis. Without bells and whistles, FoveaBox achieves state-of-the-art single model performance on the standard COCO and Pascal VOC object detection benchmark. More importantly, FoveaBox avoids all computation and hyper-parameters related to anchor boxes, which are often sensitive to the final detection performance. We believe the simple and effective approach will serve as a solid baseline and help ease future research for object detection. The code has been made publicly available at https://github.com/taokong/FoveaBox .Comment: IEEE Transactions on Image Processing, code at: https://github.com/taokong/FoveaBo

Research on Simulation Inspection Detector

AbstractThe structure design problems of simulation inspection detector on ground are researched in this paper. The general design scheme is proposed based on the design task requirements of simulation inspection detector with a synthetic consideration on the requirements of the whole mass and the real grounded force. Detailed design for the concrete mechanical strcture has been carried out. The prototype of simulation inspection detector meets the test requirements, which can also provide important reference for the detector improvemen

An investigation of the effectiveness of prefabrication incentive policies in China

Prefabrication is a technology that can reduce the material consumption during the construction process. Thus, it is regarded as a technology that be of assistance in the pursuit of sustainable development in the construction industry. In China, a series of policies has been formulated to promote the implementation of prefabrication; however, the effectiveness of these policies has not been investigated. The aim of this paper is to evaluate the effectiveness of the current prefabrication incentive policies in China. To achieve this research aim, a policy framework was first developed in order to understand the existing policies. Then, four indicators-namely, the number of prefabricated component production enterprises, the prefabricated floor area, the prefabricated building market size, and the expected prefabricated building area ratio-were selected to evaluate each policy's effectiveness. It was found that the growth rates of these four indicators had increased slowly, and had even shown declining trends before 2015; however, with the incentive policies promulgated after 2015, the growth rates have increased. This study is of value not only in helping readers to understand the existing framework of incentive policies in China, but also in revealing the effectiveness of the identified prefabrication incentive policies. These research findings can also provide insights useful for policy formulation in other jurisdictions for the promotion of prefabrication

HIV associated cell death: Peptide-induced apoptosis restricts viral transmission.

The human immunodeficiency virus (HIV) is still a global pandemic and despite the successful use of anti-retroviral therapy, a well-established cure remains to be identified. Viral modulation of cell death has a significant role in HIV pathogenesis. Here we sought to understand the major mechanisms of HIV- induced death of lymphocytes and the effects on viral transmission. Flow cytometry analysis of lymphocytes from five latent HIV-infected patients, and HIV IIIB-infected MT2 cells demonstrated both necrosis and apoptosis to be the major mechanisms of cell death in CD4+ and CD4-/CD8- lymphocytes. Significantly, pro-apoptotic tumor necrosis factor (TNF) peptide (P13) was found to inhibit HIV-related cell death and reduced viral transmission. Whereas pro-necrotic TNF peptide (P16) had little effect on HIV-related cell death and viral transmission. Understanding mechanisms by which cell death can be manipulated may provide additional drug targets to reduce the loss of CD4+ cells and the formation of a viral reservoir in HIV infection

A REPRESENTATION OF GM-VARIATION IN WAVES BY THE VOLTERRA SYSTEM

ABSTRACT As known, the variation of the metacentric height of a ship in irregular waves is not a pure linear process, particular when a ship has large beam to draught ratio and large flare near the waterline at bow and stern. This kind of unconventional hull form is usually adopted for modern RoRo-ship, cruise-ship etc. which allows large cargo space and high service speed. In this paper, the GM-variation is derived into a function series with respect to the variation order and represented by the Volterra system. The transfer functions for the different orders are integrated numerically or analytically through expressing the sectional beam, area and moment in Taylor's series as function of the momentary water line. Thereby the explicit relationship between the hull form and GM-variation can be obtained. The numerical result has shown the significant effect of the second order term in the Volterra system on the GM-variation in waves. Hence, the non-linear characteristics of the GM-variation in an irregular wave can be easily analyzed by means of available nonlinear probability theories or Monte-Carlo simulation technique

Fermionic steering is not nonlocal in the background of dilaton black hole

We study the redistribution of the fermionic steering and the relation among fermionic Bell nonlocality, steering, and entanglement in the background of the Garfinkle-Horowitz-Strominger dilaton black hole. We analyze the meaning of the fermionic steering in terms of the Bell inequality in curved spacetime. We find that the fermionic steering, which is previously found to survive in the extreme dilaton black hole, cannot be considered to be nonlocal. We also find that the dilaton gravity can redistribute the fermionic steering, but cannot redistribute Bell nonlocality, which means that the physically inaccessible steering is also not nonlocal. Unlike the inaccessible entanglement, the inaccessible steering may increase non-monotonically with the dilaton. Furthermore, we obtain some monogamy relations between the fermionic steering and entanglement in dilaton spacetime. In addition, we show the difference between the fermionic and bosonic steering in curved spacetime.Comment: 21 pages, 4 figure

Venice: Exploring Server Architectures for Effective Resource Sharing

Consolidated server racks are quickly becoming the backbone of IT infrastructure for science, engineering, and business, alike. These servers are still largely built and organized as when they were distributed, individual entities. Given that many fields increasingly rely on analytics of huge datasets, it makes sense to support flexible resource utilization across servers to improve cost-effectiveness and performance. We introduce Venice, a family of data-center server architectures that builds a strong communication substrate as a first-class resource for server chips. Venice provides a diverse set of resource-joining mechanisms that enables user programs to efficiently leverage non-local resources. To better understand the implications of design decisions about system support for resource sharing we have constructed a hardware prototype that allows us to more accurately measure end-to-end performance of at-scale applications and to explore tradeoffs among performance, power, and resource-sharing transparency. We present results from our initial studies analyzing these tradeoffs when sharing memory, accelerators, or NICs. We find that it is particularly important to reduce or hide latency, that data-sharing access patterns should match the features of the communication channels employed, and that inter-channel collaboration can be exploited for better performance

Comparison of two pretreatment methods for mercury stable isotope analysis in Antarctic moss

Mercury (Hg) stable isotope analysis can provide new insight for understanding the biogeochemistry and sources of Hg in the polar regions. To completely extract the low contents of Hg in polar samples and to avoid isotopic fractionation during the sample preparation stage, an effective and reliable pretreatment method is needed. In this work, two different pretreatment methods were compared for measuring Hg stable isotopes in Antarctic moss samples. One method was acid digestion (HNO3︰ H2O2=5︰3, v/v) and the second was a combustion-trapping treatment with a trapping solution (HNO3:HCl=2:1, v/v). There were no significant differences in the analytical results obtained with the two methods. The overall mean values and uncertainties of total Hg (THg) and the isotopic compositions of Hg in the referenced materials were all in good agreement with the certified and reported values, indicating that both methods were accurate and applicable. Acid digestion is highly efficient, while the combustion-trapping method can be used to treat samples with low Hg content. The proposed methods were successfully used to determine the Hg isotopic compositions in moss samples collected from the Antarctic