Search NASA⌕ Search

SEARCH · Search NASA

Results for “messages”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records

Hardware MPI message matching: Insights into MPI matching behavior to inform design: Hardware MPI message matching

Here, this paper explores key differences of MPI match lists for several important United States Department of Energy (DOE) applications and proxy applications. This understanding is critical in determining the most promising hardware matching design for any given high-speed network. The results of MPI match list studies for the major open-source MPI implementations, MPICH and Open MPI, are presented, and we modify an MPI simulator, LogGOPSim, to provide match list statistics. These results are discussed in the context of several different potential design approaches to MPI matching–capable hardware. The data illustrate the requirements for different hardware designs in terms of performance and memory capacity. Finally, this paper's contributions are the collection and analysis of data to help inform hardware designers of common MPI requirements and highlight the difficulties in determining these requirements by only examining a single MPI implementation.

97 MATHEMATICS AND COMPUTING↗

Message in a Bottle—An Update to the Golden Record: 1. Objectives and Key Content of the Message

In the first part of this series, we delve into the foundational aspects of “Message in a Bottle (MIAB)” (henceforth referred to as MIAB). This study builds upon the legacy of the Voyager Golden Records, launched aboard Voyager 1 and 2 in 1977, which aimed to communicate with intelligent species beyond our world. These records not only offer a snapshot of Earth and human civilization but also represent our desire to establish contact with advanced alien civilizations. Given the absence of mutually understood signs, symbols, and semiotic conventions, MIAB, like its predecessor, uses scientific methods to design an innovative means of communication that encapsulates the story of humanity. Our goal is to share our collective knowledge, emotions, innovations, and aspirations in a way that provides a universal, yet contextually relevant, understanding of human society, the evolution of life on Earth, and our hopes and concerns for the future. Through this time and space traveling capsule, we also strive to inspire and unify current and future generations to celebrate and safeguard our shared human experience.

99 GENERAL AND MISCELLANEOUS↗

A dynamic, unified design for dedicated message matching engines for collective and point-to-point communications

The Message Passing Interface (MPI) libraries use message queues to guarantee correct message ordering between communicating processes. Message queues are in the critical path of MPI communications and thus, the performance of message queue operations can have significant impact on the performance of applications. Collective communications are widely used in MPI applications and they can have considerable impact on generating long message queues. In this paper, we propose a unified message matching mechanism that improves the message queue search time by distinguishing messages coming from point-to-point and collective communications and using a distinct message queue data structure for them. For collective operations, it dynamically profiles the impact of each collective call on message queues during the application runtime and uses this information to adapt the message queue data structure for each collective dynamically. Moreover, we use a partner/non-partner message queue data structure for the messages coming from point-to-point communications. The proposed approach can successfully reduce the queue search time while maintaining scalable memory consumption. The evaluation results show that we can obtain up to 5.5x runtime speedup for applications with long list traversals. Moreover, we can gain up to 15% and 94% queue search time improvement for all elements in applications with short and medium list traversals, respectively.

97 MATHEMATICS AND COMPUTING↗

Extending OpenSHMEM with Aggregation Support for Improved Message Rate Performance

OpenSHMEM is a highly efficient one-sided communication API that implements the PGAS parallel programming model, and is known for its low latency communication operations that can be mapped efficiently to RDMA capabilities of network interconnects. However, applications that use OpenSHMEM can be sensitive to point-to-point message rates, as many-to-many communication patterns can generate large amounts of small messages which tend to overwhelm network hardware that has predominantly been optimised for bandwidth over message rate. Additionally, many important emerging classes of problems such as data analytics are similarly troublesome for the irregular access patterns they employ. Message aggregation strategies have been proven to significantly enhance network performance, but their implementation often involves complex restructuring of user code, making them unwieldy. This paper shows how to combine the best qualities of message aggregation within the communication model of OpenSHMEM such that applications with small and irregular access patterns can improve network performance while maintaining their algorithmic simplicity. We do this by providing a path to a message aggregation framework called conveyors through a minimally intrusive OpenSHMEM extension introducing aggregation contexts that fit more naturally to the OpenSHMEM atomics, gets, and puts model. We test these extensions using four of the bale 3.0 applications which contain essential many-to-many access patterns to show how they can produce performance improvements of up to 65×.

Welch, Aaron↗

E(n)-Equivariant cartesian tensor message passing interatomic potential

Machine learning potential (MLP) has been a popular topic in recent years for its capability to replace expensive first-principles calculations in some large systems. Meanwhile, message passing networks have gained significant attention due to their remarkable accuracy, and a wave of message passing networks based on Cartesian coordinates has emerged. However, the information of the node in these models is usually limited to scalars, and vectors. In this work, we propose High-order Tensor message Passing interatomic Potential (HotPP), an E(n) equivariant message passing neural network that extends the node embedding and message to an arbitrary order tensor. By performing some basic equivariant operations, high order tensors can be coupled very simply and thus the model can make direct predictions of high-order tensors such as dipole moments and polarizabilities without any modifications. The tests in several datasets show that HotPP not only achieves high accuracy in predicting target properties, but also successfully performs tasks such as calculating phonon spectra, infrared spectra, and Raman spectra, demonstrating its potential as a tool for future research.

97 MATHEMATICS AND COMPUTING↗

Implementation of ISO 15118-202 messages within Everest EV Charging Open Source Framework [SWR-25-56]

This software implements the messages defined in the ISO 15118-202 standard within the Everest EV Charging open source framework. The protocol and messages defined in the ISO 15118-202 standard enable the exchange of additional information which is not available for exchange within the currently deployed EV/EVSE communications protocols. This information includes co-identification parameters, error message exchange and more. This fork of the everest-core repository adds a prototype of the Extensible Supply Equipment Communication Controller (SECC) Discovery Protocol (ESDP) implemented based on a draft of the ISO 15118-202 standard. This is achieved through additions and modifications to the EvseV2G module. The implementation provides a demonstration of the ESDP messages, encoding and decoding but does not include a full integration within the Everest framework. Much of the information being sent over ESDP in this implementation is set statically for the sake of demonstrating the protocol itself. This fork of the ext-switchev-iso15118 repository adds a prototype of the Extensible Supply Equipment Communication Controller (SECC) Discovery Protocol (ESDP) implemented based on a draft of the ISO 15118-202 standard. The implementation provides a demonstration of the ESDP messages, encoding and decoding but does not include a full integration within the Everest framework. Much of the information being sent over ESDP in this implementation is set statically for the sake of demonstrating the protocol itself. This fork adds the ESDP features for only the EVCC controller because that is the only portion that is utilized in the everest Software-in-the-Loop.

Watt, Ed [National Renewable Energy Laboratory (NR↗

Public expectations of and responses to WEA message content

Risk communication is crucial to building resilient communities because it allows multi-directional information exchange about a hazard event and its associated risks among stakeholders, and it seeks to promote protective behavior among at-risk populations. Public response to alerts and warnings and inclination to take protective action, however, are influenced by several factors, including message content and style (accuracy, consistency, and clarity), message source and frequency of delivery, language and technologies used for dissemination, and the socio-psychological characteristics of message recipients. Using the Protective Action Decision Model (PADM), this chapter examines the role of language preference of at-risk individuals on their response to alerts received from authoritative sources (i.e., Wireless Emergency Alert (WEA) messages) and via Online Social Networks (OSN) (i.e., social media). An analysis of survey responses of a sample of residents of the Mississippi Gulf Coast was conducted to determine the (1) socioeconomic characteristics influencing public response to warnings – specifically, response to evacuation notice; and (2) role of language preference on public use of specific communication channel. The southeastern United States is home to diverse ethnic and sociocultural communities whose first language is not English. The results of this study provide evidence that will contribute to efforts to make risk communication more inclusive of greater segments of society, ensure integration of local knowledge, and contextualize messages to promote more effective public response.

Kar, Bandana↗

Chain of Custody Item Monitor Message Viewer v.1.0 Beta

The CoCIM Message Viewer software allows users to connect to and download messages from a Chain of Custody Item Monitor (CoCIM) connected to a serial port on the user’s computer. The downloaded messages are authenticated and displayed in a Graphical User Interface that allows the user a limited degree of sorting and filtering of the downloaded messages as well as the ability to save downloaded files or to open previously downloaded message history files.

Schwartz, Steven Robert↗

Sequence Hopping Algorithm For Securing Goose Messages

Embodiments of the present invention include methods and apparatuses for securing data transfer in power-system automation and smart grids. Embodiments of the present invention can be particularly helpful in securing GOOSE messages. A method of securing data transfer according to an embodiment of the present invention can include a message sequence synchronization and monitoring server (MSSMS) providing random seeds to a publisher intelligent electronic device (IED) and a subscriber IED, both having a pseudo random number generators (PRNGs), inputting the random seeds into the PRNG of the publisher IED and generating a publisher sequence hopping number, sending a message to the subscriber IED with the publisher sequence hopping number attached, and determining if the message is valid by comparing the message attached publisher sequence hopping number to a subscriber sequence hopping number generated by the subscriber PRNG.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Data-Centric Communication Framework for Multicast IEC 61850 Routable GOOSE Messages over the WAN in Modern Power Systems

In this paper, a data-centric communication framework is proposed for multicast routable generic object-oriented substation event (GOOSE) messages (MRGM) over the wide area network (WAN) for effective substation-to-substation (SS2SS) and substation to control center (SS2CC) communications. In this structure, the IEC 61850 GOOSE message is transmitted over the WAN using the data distribution service (DDS) as a fast, reliable, and secure data-centric communication middleware. The main feature of this framework is its multicast capability, where several authorized subscribers can receive a published message simultaneously. This can significantly improve the system monitoring and control of the protection systems in modern smart grids, where intelligent schemes can be applied. The effectiveness of the proposed platform, in terms of total end-to-end delay between participants, is evaluated through experimental results obtained from the actual hardware-based test setup developed at the Florida International University (FIU) smart grid testbed. The results demonstrate that the latency between sending and receiving a GOOSE message among participants is within its maximum time span defined by the IEC 61850-90-5 working group for communications over the WAN.

42 ENGINEERING↗

Using Simulation to Examine the Effect of MPI Message Matching Costs on Application Performance

Attaining high performance with MPI applications requires efficient message matching to minimize message processing overheads and the latency these overheads introduce into application communication. We use a validated simulation-based approach to examine the relationship between MPI message matching performance and application time-to-solution. Specifically, we examine how the performance of several important HPC workloads is affected by the time required for matching. Our analysis yields several important contributions: (i) the performance of current workloads is unlikely to be significantly affected by MPI matching unless match queue operations get much slower or match queues get much longer; (ii) match queue designs that provide sublinear performance as a function of queue length are unlikely to yield much benefit unless match queue lengths increase dramatically; and (iii) we provide guidance on how long the mean time per match attempt may be without significantly affecting application performance. The results and analysis in this paper provide valuable guidance on the design and development of MPI message match queues.

97 MATHEMATICS AND COMPUTING↗

dCache – Efficient Message Encoding For Inter-Service Communication in dCache: Evaluation of Existing Serialization Protocols as a Replacement for Java Object Serialization

As a well established, large-scale distributed storage system, dCache is used to manage and serve huge amounts of data collected by high energy physics, astrophysics and photon science experiments. Based on a microservices-like architecture, dCache is built as a modular distributed system, where each component provides a different core functionality. These services communicate by passing serialized messages to each other, a core behavior whose performance properties can consequently affect the entire system.This paper compares and evaluates different data serialization protocols in computer science with the objective of replacing and improving upon Java Object Serialization (JOS), which has increasingly presented itself as no longer being sufficiently performant for encoding messages. The criteria for choosing a new framework are collected, analyzed and formalized. The primary motivation for replacing Java serialization for encoding dCache messages is increasing the general speed of message-passing and thereby reducing the round-trip time for user requests. Emphasis is also placed on schema evolution capabilities and framework usability. Approaches for generalizing (de)serialization speed and size measurements based on data structure complexity are introduced, criteria for measuring documentation, learning curve, maintainability and introduction effort are defined. Finally, several selected serialization protocols are evaluated and compared accordingly, concluding with a recommendation for a suitable JOS replacement.

Morschel, Lea↗

On the Performance of Detecting Injection of Fabricated Messages into the CAN Bus

There have been several public demonstrations of attacks on connected vehicles showing the ability of an attacker to take control of a targeted vehicle by injecting messages into their Controller Area Network (CAN) bus. In this article, using injected speed reading and Revolutions Per Minute (RPM) reading messages in in-motion vehicle, we examine the ability of the Pearson correlation and the unsupervised learning methods k-means clustering and Hidden Markov Model (HMM) to differentiate ’no-attack’ and ’under-attack’ states of the given vehicle. We found that the Pearson correlation distinguishes the two states, the k-means clustering method has an acceptable accuracy but high false positive rate and HMM detects attacks with acceptable detection rate but has a high false positive in detecting attacks from speed readings when there is no attack. The accuracy of these unsupervised learning methods are comparable to the ones of the supervised learning methods used by CAN bus Intrusion Detection System (IDS) suppliers. In addition, the article shows that studying CAN anomaly detection techniques using off-vehicle test facilities may not properly evaluate the performance of the detection techniques. Finally, the results suggest using other features besides the data content of the CAN messages and integrate knowledge about how the Electronic Control Units (ECUs) collaborate in building effective techniques for the detection of injection of fabricated message attacks.

97 MATHEMATICS AND COMPUTING↗

CSlib, a library to couple codes via Client/Server messaging

The CSlib is a small, portable library which enables two (or more) independent simulation codes to be coupled, by exchanging messages with each other. Both codes link to the library when they are built, and can them communicate with each other as they run. The messages contain data or instructions that the two codes send back-and-forth to each other. The messaging can take place via files, sockets, or MPI. The latter is a standard distributed-memory message-passing library.

Plimpton, Steve↗

Messaging for Impact: Behavioral Science-Based Communication Strategies to Advance Energy Efficiency

Currently, five legal authorities require U.S. federal agencies to purchase energy-efficient products. However, compliance with these requirements has consistently been low (~55%). Recent surveys indicate that energy efficiency requirements are not communicated properly within federal agencies and energy-efficiency is not a top priority. In the constantly evolving energy industry, with many solutions for a clean energy future, effective communication methods are vital for widespread adoption of energy efficiency. We have been conducting experiments within the U.S. federal sector that test the effectiveness of messaging strategies developed by using behavioral science principles like loss aversion, framing, and herd behavior. This will identify effective communications methods that encourage energy efficiency adoption. In this study, we measure the effectiveness of different communication strategies by monitoring the web traffic of hyperlinks placed within our digital communications and outreach materials. To determine effective strategies that influence federal buyer behavior, the web traffic from subjects that received the behavioral science-based messaging (treatment group) is compared to that from subjects that received regular messaging (control group) for each of the strategies. This paper provides an overview of the behavioral science principles that we applied, data collection methods, and results of our analysis. Since the lack of effective communication of energy-efficiency policies is also a common problem in the private sector, the messaging strategies developed in this study can be applicable to other large private sector institutions

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Reduced number of counters for reliable messaging

A shared memory maintained by sender processes stores a sequence number counter per destination process. A sender process increments the sequence number counter in the shared memory in sending a message to a destination process. The sender process sends a data packet comprising the message and at least a sequence number specified by the sequence number counter. All of the sender processes share a sequence number counter per destination process, each of the sender processes incrementing the sequence number counter in sending a respective message. Receiver processes run on the hardware processor, each of the receiver processes maintaining a local memory counter on the memory, the local memory counter associated with a sending node. The local memory counter stores a sequence number of a message received from the sending node. The receiver process delivers incoming data packets ordered by sequence numbers of the data packets.

Kumar, Sameer↗