Open-source Stack Research Articles

Mixed-Integer Motion Planning on German Roads Within the Apollo Driving Stack

Traffic situations with interacting participants pose difficulties for today’s autonomous vehicles to interpret situations and eventually achieve their own mission goal. Interactive planning approaches are promising solutions for solving such situations. However, most approaches are only assessed in simulation, as researchers lack the resources to operate an autonomous vehicle. Likewise, open-source stacks for autonomous driving, such as Apollo, provide competitive and resource-efficient state-of-the-art planning algorithms. However, promising planning concepts from research are usually not included within a reasonable time, possibly due to resource restrictions or technical limitations. Without evaluating these novel algorithms in reality, the benefits and shortcomings of proposed approaches cannot be thoroughly assessed. This work aims to contribute methodology and implementation to integrate a novel mixed-integer optimization-based planning algorithm in Apollo’s planning component and assess its performance and real-time capability in theory and practice. It discusses the necessary modifications of Apollo for deployment on a different vehicle and presents three real-world driving experiments on a public road alongside a detailed experience report. The driving experiments show a smooth trajectory tracking performance operating robustly under varying perception data quality and the real-time capability of the closed-loop system.

Distributed tracing of OPC UA method calls

With increasing digitalization, shopfloor architectures transition to service-oriented, distributed layouts in which the complexity of monitoring communication between systems becomes a major challenge. Distributed tracing assists in establishing causality and hence supports the analysis of latency aspects, wrongly configured communication endpoints, and bottlenecks. In this paper, we present a first feasibility study, which investigates to what extent it is possible to trace OPC UA method calls in a distributed manner using the Zipkin framework. We show how this standard can be used in conjunction with the Eclipse Milo OPC UA open source stack and how it can be integrated into our industry demonstrator “Factory in a Box”.

DATA IMPUTATION OF MISSING VALUES FROM MARINE SYSTEMS SENSOR DATA. EVALUATION, VISUALISATION, AND SENSOR FAILURE DETECTION

To enable Condition-Based maintenance, sensors need to be installed, and thus Internet of Ships (IoS) needs to be implemented. IoS presents several challenges, an example of which is the imputation of missing values. A data assessment imputation framework that is utilised to assess the accuracy of any imputation model is presented. To complement this study, a real-time imputation tool is proposed based on an open-source stack. A case study on a total of 4 machinery systems parameters obtained from sensors installed on a cargo vessel is presented to highlight the implementation of this framework. The multivariate imputation technique is performed by applying Kernel Ridge Regression (KRR). As the explanatory variables may also contain missing values, GA-ARIMA is utilised as the univariate imputation technique. The case study results demonstrate the applicability of the suggested framework in the case of marine machinery systems.

The new (and improved!) CERN Single-Sign-On

The new CERN Single-Sign-On (SSO), built around an open source stack, has been in production for over a year and many CERN users are already familiar with its approach to authentication, either as a developer or as an end user. What is visible upon logging in, however, is only the tip of the iceberg. Behind the scenes there has been a significant amount of work taking place to migrate accounts management and to decouple Kerberos [1] authentication from legacy Microsoft components. Along the way the team has been engaging with the community through multiple fora, to make sure that a solution is provided that not only replaces functionality but also improves the user experience for all CERN members. This paper will summarise key evolutions and clarify what is to come in the future.

Performance analysis of the lamp stack compared to its variants in a single page web application environment

For over two decades, the LAMP stack has been one of the most popular open-source application stacks for web development. As the web ecosystem has evolved and new open source software has been made...

Ethernet TCP/IP-Based Audio Interface for DSP System Verification

With advances in digital technologies, development and verification of DSP audio systems are becoming more and more challenging. Due to high communication requirements introduced with surround audio channel- and latest object-based technologies such as DTS:X and Dolby Atmos, computer's sound card capabilites are expanded with an external audio interface for exchanging high-resolution content between computer and DSP device under test. In this article, the Ethernet TCP/IP-based audio interface solution is proposed. The main idea was to come with the cost-effective communication solution using standard Ethernet IEEE 802.3 hardware, free open-source network stacks, and finally implementing TCP application protocol in point-to-point topology instead of porting custom UDP streaming protocol. Experiments conducted in order to observe overall performance of the system indicate that expected throughput is achieved, but at the cost of long delays and high memory consumption.

Open Geospatial Tools for Movement Data Exploration

Movement data exploration presents a significant challenge due to the heterogeneity of movement datasets and analysis tasks. Furthermore, there is a lack of established tools for the exploratory analysis of movement data, as well as a lack of literature on best practices for applying corresponding concepts using commonly available data analysis tools. To address this gap, we present three open-source technology stacks for the exploratory analysis of movement data and discuss their capabilities and limitations.

BUILDING A BILLION SPATIO-TEMPORAL OBJECT SEARCH AND VISUALIZATION PLATFORM

Abstract. With funding from the Sloan Foundation and Harvard Dataverse, the Harvard Center for Geographic Analysis (CGA) has developed a prototype spatio-temporal visualization platform called the Billion Object Platform or BOP. The goal of the project is to lower barriers for scholars who wish to access large, streaming, spatio-temporal datasets. The BOP is now loaded with the latest billion geo-tweets, and is fed a real-time stream of about 1 million tweets per day. The geo-tweets are enriched with sentiment and census/admin boundary codes when they enter the system. The system is open source and is currently hosted on Massachusetts Open Cloud (MOC), an OpenStack environment with all components deployed in Docker orchestrated by Kontena. This paper will provide an overview of the BOP architecture, which is built on an open source stack consisting of Apache Lucene, Solr, Kafka, Zookeeper, Swagger, scikit-learn, OpenLayers, and AngularJS. The paper will further discuss the approach used for harvesting, enriching, streaming, storing, indexing, visualizing and querying a billion streaming geo-tweets.

Cloud-based Satellite Image Processing Service by Open Source Stack: A KARI Case

Cloud-based Satellite Image Processing Service by Open Source Stack: A KARI Case

Implementation of an OpenFlow-based Access Point Virtual Switch for Monitoring and Virtualization of Legacy Wireless LAN

Network virtualization is an emerging technology for solving the rigidity of the physical network infrastructure. The innovative technique virtualizes all resources in the network, including the network links and nodes, and provides a number of virtual networks on a single network infrastructure. In order to realize a virtual network, a thorough and complete monitoring of all resources in the network should be performed firstly. OpenFlow is an open source stack for network virtualization. However, it is impossible to apply OpenFlow to AP-based legacy wireless LAN environment because OpenFlow targets ethernet-based LAN environment. In this paper, we implement an adaptor-styled virtual switch for AP-based wireless LAN through customizing the Open vSwitch which is a virtual switch of OpenFlow. The evaluation test results show that the implemented OpenFlow stack operates successfully. The implemented OpenFlow stack can now be plugged immediately in existing AP-based wireless LAN environment and plays network resource monitoring. In the future, we can develop wireless LAN virtualization applications on the wireless OpenFlow stack.

Mobile app approach by open source stack for satellite images utilization

Mobile apps in information communication technology is regarded as the dominant trend from many application fields covering science and engineering. However, most mobile apps in the application communities dealing with satellite image data sets are somewhat on the limited level, and it is generally the case that air-photos or high-resolution satellite images are used for the background for other contents services. Along with the current status and latent possibility of mobile analytics, it is necessary to design and implement a sort of practical mobile app for satellite images utilization. The mobile device used in this study is a android-driven smartphone. The main functionalities with mobile apps in this study are geo-metadata searching and browsing interlinked with embedded database, vector layer overlay from users’ local data sets, actual image processing by mobile gesture requesting and geo-database server connection. Especially, examples for satellite image processing provided by this approach emphasize the filtering or detection level such as line segmentation, edge detection and corner point detection. It is practicable to implement its extension to customize and optimize the target applications along with more users’ requirements. Furthermore, all these tasks in both mobile client and server are carried out on open source stacks. It is expected that this study can be a meaningful attempt or an application model to develop more practical mobile apps for remote sensing images and geo-based contents.

Design of a CANopen Slave Node Based on AT90CAN128

As an application layer protocol of CAN bus, CANopen has wide application in industry. This paper presents a kind of CANopen slave node based on AVR hardware platform of AT90CAN128. Firstly the structure of the slave node hardware platform of the AVR microcontroller AT90CAN128 and CAN bus control based on embedded CAN driver module CTM1050 is proposed. Then the open-source protocol stack CANFestival software design and the specific method are described. CANopen network testing platform is built to test the design of the CANopen slave node. The experimental results illustrate that the proposed solution and implementation method is correct and effective.

An Architectural Insight into the National Online Examination System

Online examination system has been developed as per requirement of NASSCOM and DIT. The system can cater to a large number of students for administering multiple choice questions and True-False Questions of various subjects. System offers Dynamic paper generation using 3 parameter model based on Item response theory. Flex, Spring and Hibernate frameworks have been used for development of system and it is highly secure and fail safe. The system uses open source stack in its design and is extensible, reliable and scalable to handle future requirements. The system is further designed to support very large load using cloud computing paradigm. The paper presents the functional description and architectural design of the system along with Adaptive exam conduction model used. Index Terms—Online examination software, flex, spring, blazeds, terracotta, hibernate, eucalyptus, cloud computing.

Matching Open Source Software Licenses with Corresponding Business Models

Scores of software producers have turned toward open source licenses to improve service for their customers. For these companies, choosing the correct license determines business success. When the available open source stack and licensing options grow, so does the need to understand the interplay among licensing, sourcing decisions, and business goals. A model of license choice emphasizes different licenses and rationalizes the choice of an open source software (OSS) license. This is crucial for smaller companies and start-ups that don't have the tools and knowledge to perform a thorough investigation of all the consequences of their license choice every time they employ OSS.

Research of CANopen Slave Node Based on Embedded System

As a typical application layer protocol of CAN-bus, CANopen has been widely accepted in many fields. In this paper, CanFestival, which is a kind of open-source CANopen stack, is briefly introduced. The implementation scheme of CANopen slave node is proposed, which is based on a kind of AVR microcontroller-AT90CAN128 and open-source CANopen stack-CanFestival. In this paper the hardware design of slave node and the open-source protocol stack transplant have completed successfully. The debugging experiment of this slave node communication has been carried out, and the correctness of the scheme of hardware design and software transplant is verified by debugging experiment results in this paper.

Open source meets venture capital

Long-established vendors such as IBM and Novell have announced or strengthened their open source offerings from the data server to the desktop, sometimes offering and supporting certified versions of open source applications, sometimes using open source code in new server-based configurations that let customers choose specific functionalities per user. New companies such as SpikeSource, a San Francisco-based startup offering integrated, validated, and certified open source stacks with ongoing maintenance and support services, are convincing venture capitalists the open source stack is a viable investment. Open source development houses themselves are being recognized for delivering standalone best-of-breed technology - such as the Java application server JBoss - or as valuable acquisitions in a larger vendor's portfolio.