Key Technology of Embedded System Implementation for Software-based CNC System

The software-based computer numerical control（CNC） system includes three types of tasks： periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.

New Approach for Hardware/Software Embedded System Conception Based on the Use of Design Patterns

This paper deals with a new hardware/software embedded system design methodology based on design pattern approach by development of a new design tool called smartcell. Three main constraints of embedded systems design process are investigated: the complexity, the partitioning between hardware and software aspects and the reusability. Two intermediate models are carried out in order to solve the complexity problem. The partitioning problem deals with the proposed hardware/software partitioning algorithm based on Ant Colony Optimisation. The reusability problem is resolved by synthesis of intellectual property blocks. Specification and integration of an intelligent controller on heterogeneous platform are considered to illustrate the proposed approach.

Exploration of the Integration of Software Engineering Thinking into Embedded System Design Course

Engineering practice is the key bridge between college education and actual work in the industry.In order to deliver qualified talents with engineering quality to the industry,this paper explores integrating software engineering thinking into the Embedded System Design course.A practical and effective teaching mode is designed consisting of immersive learning,case-based learning,progressive practice,interactive learning,and autonomous learning.Through this teaching mode,multi-levels of closed-loop have been established including final project cycle closed-loop,testing cycle closed-loop,and product cycle closed-loop.During this process,students gradually transition to putting forward product requirements,carrying out design and development,thinking and solving problems,collaborating,and assuring quality from the perspective of software engineering.The practice results show that students’engineering quality has been significantly improved.

LXI instrument development platform based on an open embedded operating system

This paper introduces the architecture and components of LXI instrument development platform based on an open embedded operating system,which is a modular and configurable platform.The platform is a total solution to develop LXI instrument modules and systems.On the other hand,it also supports other types of instrument development.This is a generic and efficient platform.At the end,this paper addresses the technical tends, challenges,and recormnends solutions.

基于iSYSTEM的嵌入式软件分析

随着嵌入式系统应用的不断深入,新的应用环境和产业需求对嵌入式系统提出了更高的要求。因此,基于NXP MPC5744P控制器,采用iSYSTEM公司的硬件产品BlueBox IC5700及软件产品winIDEA对嵌入式软件进行软件时间及代码覆盖率测量分析,以此来提高软件质量和软件可靠性。

A Product Line Approach to Design an Embedded Web System for Healthcare

With the recent advances in mobile technology and wireless network technology, embedded systems are being widely used in modem society today. Particularly, a home healthcare system is a networked embedded system where the main functions are to control the disease processes and to help patients maintain their independence and maximum level of function within their own homes and communities. It seems to be self-evident to design a system that would support both patients and their healthcare providers in the process of treatment. Nevertheless, little work in integrating embedded devices with intemet for the support of patients have been done to date. In this paper, we show how to design a healthcare system for supporting the management of the conditions of patients with chronic diseases. This system is built around wireless networked embedded devices, and integrates the intemet technology for telemonitoring the patient＇s health and notifying of doctors if emergency action is required. Also, patients themselves may specify personal alerts for condition-related issues.

On modeling approach for embedded real-time software simulation testing

Modeling technology has been introduced into software testing field. However, how to carry through the testing modeling effectively is still a difficulty. Based on combination of simulation modeling technology and embedded real-time software testing method, the process of simulation testing modeling is studied first. And then, the supporting environment of simulation testing modeling is put forward. Furthermore, an approach of embedded real-time software simulation testing modeling including modeling of cross-linked equipments of system under testing （SUT）, test case, testing scheduling, and testing system service is brought forward. Finally, the formalized description and execution system of testing models are given, with which we can realize real-time, closed loop, mad automated system testing for embedded real-time software.

Real-time embedded software testing method based on extended finite state machine

The reliability of real-time embedded software directly determines the reliability of the whole real-time embedded sys- tem, and the effective software testing is an important way to ensure software quality and reliability. Based on the analysis of the characteristics of real-time embedded software, the formal method is introduced into the real-time embedded software testing field and the real-time extended finite state machine （RT-EFSM） model is studied firstly. Then, the time zone division method of real-time embedded system is presented and the definition and description methods of time-constrained transition equivalence class （timeCTEC） are presented. Furthermore, the approaches of the testing sequence and test case generation are put forward. Finally, the proposed method is applied to a typical avionics real- time embedded software testing practice and the examples of the timeCTEC, testing sequences and test cases are given. With the analysis of the testing result, the application verification shows that the proposed method can effectively describe the real-time embedded software state transition characteristics and real-time requirements and play the advantages of the formal methods in accuracy, effectiveness and the automation supporting. Combined with the testing platform, the real-time, closed loop and automated simulation testing for real-time embedded software can be realized effectively.

LabVIEW-based auto-timing counts virtual instrument system with ORTEC 974 Counter/Timer

In order to achieve the auto-timing counts measurement of nuclear radiation using ORTEC 974 Counter/Timer, an auto-timing counts virtual instrument system based on the LabVIEW virtual instrument development platform and GPIB instrument control and transmission bus protocol is designed in this paper. By introducing software timing technique, the minimum time base of factory setting improves from 0.1 s to 0.03 s. The timing counts performance and longtime stability are also discussed in detail. The automatic data recording and saving facilitates data analysis and processing. Its real-time display and statistic function is very convenient for monitoring the nuclear radiation.

Software defined satellite networks:A survey

In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the growing challenges induced by time-varying topology,intermittent inter-satellite link and dramatically increased satellite constellation size.This survey covers the latest progress of software defined satellite networks,including key techniques,existing solutions,challenges,opportunities,and simulation tools.To the best of our knowledge,this paper is the most comprehensive survey that covers the latest progress of software defined satellite networks.An open GitHub repository is further created where the latest papers on this topic will be tracked and updated periodically.Compared with these existing surveys,this survey contributes from three aspects:(1)an up-to-date SDN-oriented review for the latest progress of key techniques and solutions in software defined satellite networks;(2)an inspiring summary of existing challenges,new research opportunities and publicly available simulation tools for follow-up studies;(3)an effort of building a public repository to track new results.

A hardware/software co-optimization approach for embedded software of MP3 decoder

In order to improve the efficiency of embedded software running on processor core, this paper proposes a hard-ware/software co-optimization approach for embedded software from the system point of view. The proposed stepwise methods aim at exploiting the structure and the resources of the processor as much as possible for software algorithm optimization. To achieve low memory usage and low frequency need for the same performance, this co-optimization approach was used to optimize embedded software of MP3 decoder based on a 16-bit fixed-point DSP core. After the optimization, the results of decoding 128 kbps, 44.1 kHz stereo MP3 on DSP evaluation platform need 45.9 MIPS and 20.4 kbytes memory space. The optimization rate achieves 65.6% for memory and 49.6% for frequency respectively compared with the results by compiler using floating-point computation. The experimental result indicates the availability of the hardware/software co-optimization approach depending on the algorithm and architecture.

Tailoring of onboard system software

Tailoring of an operating system and an in embedded real-time operating system in particular is es-sential for both, kernel and operation. But many of current embedded real-time operating systems provide somebasic tailoring at the cost of depleting the flexibility of hardware, which causes the lack of flexibility, and de-grades their tailors. A layered modular tailoring model has been proposed together with some tailoring operationsto improve the flexibility of the systems, and algorithms have been proposed for verification of tailoring opera-tions with the current operating system.

Human Comfort Instrument Design Based on Embedded

The traditional human comfort meter has the following defects: the interface is not uniform;the operation is cumbersome and complicated;the interface is unfriendly, and the stability and adaptability are poor. This paper presents a design scheme for human comfort instrument based on embedded system, using S3C2440 embedded development board and the sensors to collect the real-time temperature, relative humidity and wind speed data and to process the collecting data;then obtaining the human body comfort value according to the basic algorithm of human body comfort instrument;giving the human comfort conclusion according to the diastolic index range of human comfort, and showing the temperature and humidity, wind speed, comfort value and conclusion through writing the Qt graphical user interface program. At the same time, the human comfort instrument has the data storage function. The human comfort instrument is high in integration, strong in real time, high in sensitivity, stable and reliable, and it meets the development goals of the intelligent meteorological service, and meets the demand of the meteorological service that is closer to life, and it has broad development prospect.

Think upon Cultivating Domestic High-class Practitioners of Industrial Embedded Software Development

Domestic situation of embedded software practitioners in the industry field is analyzed in this paper,based on which the new requirements for personnel working for embedded software R&D are proposed.Then reform notions in higher education system upon cultivating high-class practitioners are presented.

Telecom-Oriented Embedded Software Support Platform

This paper presents an embedded software platform used in the telecom field.The platform consists of the Virtual Operating System (VOS)layer,core layer, protection layer and module layer.It supports and simplifies upper application software of telecom systems.In addition to basic modules and functions, its instance scheduling model and distributed process communication are detailed in the paper.

An Embedded Software Modeling and Process by Using Aspect-Oriented Approach

In recent years, mobile devices have become widespread and refined, and they have offered increased convenience in human life. For these reasons, a variety of embedded systems have been designed. Therefore, improving methods for developing of embedded software systematically has become an important issue. Platform-based design is one example of an embedded-system design method that can reduce the design cost via improving a design’s abstraction level. However, platform-based design lacks precise definitions for platforms and design processes. This paper provides an approach that combines the aspects and platform-based design methods for developing embedded software. The approach is built on platform-based design methodology and uses the separating of concerns (SoC) concept to define the aspects and to reduce the crosscutting concerns in embedded system modeling. For aspect issues, we use the extended UML notation with aspects to describe both the static structure and the dynamic structure of the embedded system. We used an example of a digital photo frame system to demonstrate our approach.

基于概率逻辑推理的高阶互补云API推荐方法

云时代,云API作为服务交付、数据交换和能力复制的最佳载体,已成长为当今面向服务软件开发和企业数字化转型不可或缺的核心要素.然而动态开放网络中持续增长的云API在给开发者提供了更多选择的同时,也将其淹没在海量的云API选择之中,设计有效的云API推荐方法就此成为API经济健康发展中迫切要解决的现实问题.但是,现有研究主要利用搜索关键词、服务质量和调用偏好进行建模,生成质量高功能单一的云API推荐列表,没有考虑服务化软件实际开发中开发者对多元化高阶互补云API的客观需要.高阶互补云API推荐旨在为多个查询云API生成多元互补云API列表,要求推荐结果与查询云API均互补,以满足开发者的联合需求.针对此问题,本文提出基于概率逻辑推理的高阶互补云API推荐方法(Probabilistic Logic Reasoning for High-order Complementary Cloud API Recom⁃mendation,PLR4HCCR).首先,通过云API生态真实数据分析论证云API互补推荐需求的必要性和互补关系建模中替补噪声的客观存在,为云API互补推荐问题研究提供动机和数据支持.其次,采用Beta概率嵌入对云API及其之间的关系约束进行编码,以刻画云API间互补关系的不确定性和支持互补逻辑推理.接着,设计由投影、取反和交并三个基本逻辑算子构建的互补关系逻辑推理网络,使查询集中的每个云API获得非对称互补关系感知和替补噪声消解约束下的互补云API表示.然后,引入注意力机制为查询云API的互补云API分配不同权重,增强高阶互补云API基向量的表征能力.在此基础上,采用KL散度度量高阶互补云API基向量与候选云API之间的距离,并根据KL散度排序生成高阶互补性可感知下的云API推荐结果.最后,我们利用两个真实云API数据集在不同阶互补推荐场景下进行实验,实验表明,与传统启发式推荐方法和深度学习推荐方法相比,PLR4HCCR在互补关系感知推理和替补噪声消解方面均具有较大的优势,继而使其在低阶、高阶和混合阶互补云API推荐中均展示出更优的推荐效果和更强的泛化能力.进一步,超参数敏感性实验、实例分析和用户调查验证了方法的有效性、实用性和可行性,这使结合高阶互补关系的云API推荐方法PLR4HCCR不仅更有可能生成开发者满意的结果,而且可有效提升云API服务提供者的收益.

嵌入式服务器软件接口通信容量调节算法仿真

考虑到实际系统中不同用户对通信有着不同的容量需求,为了在有限的频谱资源中获得更大的容量效果,提出一种嵌入式服务器软件接口通信容量调节算法。通过用户的信道增益信息,获取最小蜂窝用户数量。根据吞吐量增量降序排列结果,将排名靠前的蜂窝用户通信容量分配给用户对。将嵌入式服务器软件接口通信容量调节问题,转换为随机网络优化问题,对数据包码长和发送功率联合优化,引入离线算法的思想,提出通信容量调节算法,完成嵌入式服务器软件接口通信容量调节。实验结果表明,所提算法可以有效提升吞吐总量,同时能够有效降低平均等待调节延时,平均等待调节时延保持在30ms以内。

轻量级嵌入式软件自动化测试框架设计

为满足嵌入式软件测试过程中测试数据的快速生成与输入,采用数据与关键字驱动的混合驱动方法对嵌入式软件自动化测试框架进行设计。通过对嵌入式软件自动化测试框架的研究,明确测试框架设计的难点;对软件测试数据的组成与结构进行分析,构建数据与关键字驱动模型并对其生成与输入算法进行设计,根据模型实现复杂多接口测试数据的快速生成与输入。采用模块化思想,利用多线程原理对该轻量级测试框架进行设计与实现,通过实例验证该框架能够实现测试数据的自动生成与快速输入,提升测试效率。