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According to a survey, the proportion of elderly population in China continues to rise, and most old people fall due to diseases, aging, visual impairment or other problems frequently. In this regard, the "Intelligent Anti-fall Vest For The Elderly" proposed a feasible solution. The product is composed of three modules: anti-collision, fall monitoring, positioning and rescuing. The functional circuit of the product is based on the STM32F103rct6 microcontroller, which controls the HC-SR04 ultrasonic sensor to measure the distance between the wearer and the obstacle to realize the anti-collision function, controls the MPU6050 six-axis sensor to measure the wearer’s body acceleration vector amplitude and attitude angle to realize the fall monitoring function, and controls the GPS to obtain the wearer’s position information, controls the Wi-Fi module networking, and use the MQTT protocol , through the single-chip microcomputer and Alibaba Cloud platform for data interaction, to realize the positioning and rescuing function.

Neural network robustness has been a hot research topic since the discovery of adversarial examples. With the increasing threats posed by adversarial examples in safety-critical AI applications, the research problem of how to boost the robustness of neural networks has drawn even more attention in recent years. In this paper, we argue that existing methods for neural network robustness optimization primarily focus on increasing the minimum adversarial perturbation of individual datum while neglecting the purpose of the target machine learning task, i.e., classification. Consequently, we propose a neural network retraining method which implicitly enhances a model's capability in maximizing the minimum distance from data instances of all classes to the decision boundary. As demonstrated by the experiments, our method succeeds in improving the robustness of pre-trained neural networks within only a few retraining epochs while imposing little negative effect on classification accuracy, thus being applicable for online optimization of neural networks.

Network fault localization has always been a major challenge for efficient data center operation. In this paper, we propose a faulty link localization framework named “Terminator,” which provides an efficient hierarchical link probing scheme for fault localization. With both local and global probing, Terminator conserves the spine link bandwidth and localizes faulty link with high accuracy. We implement a prototype of Terminator and show that it outperforms existing benchmarks, including 007 [7], TOMO [5], PLL [6], and NetBouncer [2]. In particular, Terminator achieves an average of 37.5% internal problem-solving rate and improves the localization accuracy of 007 to nearly 100% in fat-tree topologies.

Network monitoring is a complex task and is always a trade-off between granularity of information and the performance impact of the monitoring itself on the network. SDN controllers, such as the ONOS SDN controller make this challenge easier as they can supply centralized information over the whole network. In our previous work, we analyzed the builtin detection mechanism of ONOS and revealed a lack of detection performance and the vulnerability of this process to jitter. These results have also been verified by measurements. In this paper, we present an active probing extension for the ONOS SDN controller that overcomes these shortcomings by emitting probing packets that are transmitted through the network. Packet loss is detected by calculating statistics of a list which contains data from previous packets. The evaluation by the means of measurements proves the benefits in terms of detection performance and controller load of this application. Furthermore, our extension is able to detect jitter in the data plane and to automatically adapt the probing process to these conditions.

The process of monitoring the network, especially for larger ones, is very complex and contains many pitfalls. For instance the balance between granularity of information and their performance impact on the network. With the help of SDN this challenge can become easier, as it offers new methods, mechanisms and opportunities. One of the current most important Open Source controllers is the ONOS SDN controller. According to its developers it is a production ready controller that offers high availability due to its logically centralized and physically distributed architecture. But, as our investigations show, it is unable to cope with hazardous network conditions such as sporadic or recurring packet loss. It either does not detect packet loss or only detects it after long time periods, failing all common network availability targets.

The BeiDou Navigation Satellite system is original designed to perform navigation and control tasks as an compatible, independent, open, and global navigation system. The success operating of this system in real-world environments have to overcome numerous challenges, chief among which are the BDS signal's success capture ratio, and the time resources consumed to accomplish standard positioning task. These issues are still deemed as key open challenges currently. Aimed at mitigating the aliasing artifacts brought by the way the modulation codes are tackled, and improving the BDS system performance in terms of reducing the usage of logical resources and shorten the capture time, we proposed in the current paper an acquisition method of using signal square to capture satellite signals and remove the NH implementation code interference signal. We designed a hardware system based on Xilinx XC7Z045 platform to realize the main principle and idea of the proposed method. The simulation tests are carried out to verify the effectiveness of the proposed method. Also, we compared resources cost of the proposed methods against the traditional one, it seems that the hardware circuit resources of the current method are reduced significantly. In addition to providing a novel perspective of the navigation problem, the proposed signal square stripping approach adopted in this paper paves the way to several extensions in relation to position, navigation and control of BeiDou systems, such as the transportation, mobile network synchronization and guidance & control of varied kinds of platforms and multi-agent networking systems.

Most of embedded multiprocessor platforms are ideal for running diverse operating systems and implementing different applications. Inter-processor communication interface makes it possible for an embedded multi-processor system to easily support multiple subsystems parallel processing. This paper propose a kind of OS-level communication interface implementing method based-on HPI in the Complementary Multi-processor System and present the primary principles and corresponding DSP side code structure for HPI. Take a single-board embedded multimedia system which was integrated three embedded microprocessors (PXA255, TMS320DM642 and SM501) as hardware platform, detailed description of how implement tasks communication and data transform by HPI between different embedded OS(ARM-Linux and µC/OS-II) running on ARM and DSP separately.

The domestic commercial banks build a new generation of business system by the introduction of the overseas core business system. It has become a trend over the next few years that integrating various business channels by centralizing business platforms and altering the business model based on accounting treatment into the operation model of customer-oriented. This paper reports the key technology of the new generation business system adopted by a domestic commercial bank, which has recently been online successfully as the first case in china. The new system is divided into access layer, support layer, application service layer and business system layer which respectively implements the functions of docking client, unifying data format, exchanging data, database services and etc. This paper describes the target architecture, technical support and the physical configuration of the new system. The target system includes eight application groups: The core and third part systems; The service bus; Plug-in-business system; Agency business system; Managed application System; Analysis applications System; Payment, Union Pay and other external front-end system; Fore-end serves channel and their support system. And take the process scheme of the credit management system and core business inquiring and reports printing system for example to show the effectiveness of the new system.

According to the meaning of food security, the index system for China's food security was established and the weight on each index was given by adopting AHP method. This paper made measurement and evaluation on the level of China's food security from 2001 to 2007 by using the AHP-GRA method. The results show that the model which conforms to China's actual situation can be used as a food safety pre-warning monitoring. Finally, the paper gives some effective proposals on how to promote China's Grain Security.

The latest multiprocessor platforms are ideal for implementing multi-OS embedded applications. IPC (Inter-processor communication) interface makes it possible for a multiprocessor system to easily support multiple subsystems parallel processing. In this paper, we propose a new type of OS-level communication interface designing based-on CMPS (Complementary Multi-processor System) and present the primary principles and corresponding driver structure of HPI (Host-port Interface). Take a single-board embedded multimedia system which was integrated three embedded microprocessors (PXA255, TMS320DM642 and SM501) as hardware platform, detailed description of how implement tasks communication and A/V (audio/video) data transform via HPI between different OS(Linux and mu C/OS-II) running on ARM and DSP separately.