Development, management and implementation plan for the Microwave Limb Sounder software.ABSTRACT This paper advances a Management and Implementation Plan (M/P M/P Market Price M/P Maintenance Planning M/P Merry/Pippin (Lord Of The Rings) ) for managing and controlling the development of the Microwave Limb Sounder A Microwave Limb Sounder measures (naturally-occurring) microwave thermal emission from the limb (edge) of Earth's upper atmosphere. The data is used to create vertical profiles of atmospheric gases, temperature, pressure, and cloud ice. (MLS See multilevel security. ) instrument software, and the Instrument Ground Support Equipment (IGSE IGSE Instrument Ground Support Equipment ) software. The paper is intended to be a combination of the Software Management Plan (SMP (Symmetric MultiProcessing) A multiprocessing architecture in which multiple CPUs, residing in one cabinet, share the same memory. SMP systems provide scalability. As business increases, additional CPUs can be added to absorb the increased transaction volume. ) and the Work Implementation Plan (WIP WIP Work In Progress WIP Work in Process WIP World Internet Project WIP Women in Prison (movie genre) WIP World Institute of Pain WIP Wash-In-Place WIP Women in Publishing WIP Work In Place WIP Wireless Internet Protocol ). It advances the management approach to developing the instrument software and the IGSE software that is used to test the instrument and its software. This includes the flight development phases, flight software activities, life cycle, deliverables, and other software development issues such as configuration management practices, software assurance activities, risk management and metrics reporting. 1. INTRODUCTION The Microwave Limb Sounder (MLS) is an instrument to be carried on board a NASA NASA: see National Aeronautics and Space Administration. NASA in full National Aeronautics and Space Administration Independent U.S. Earth Observing System The Earth Observing System (EOS) is a program of NASA comprising a series of artificial satellite missions and scientific instruments in Earth orbit designed for long-term global observations of the land surface, biosphere, atmosphere, and oceans of the Earth. (EOS Eos (ē`ŏs), in Greek religion and mythology, goddess of dawn; daughter of the Titans Hyperion and Theia. Every morning she arose early and preceded her brother Helios into the heavens. ) satellite. It is targeted for launch onboard the NASA's Aura spacecraft. Its objective is to measure naturally occurring microwave thermal emission Noun 1. thermal emission - the emission of electrons from very hot substances thermionic emission emission - the release of electrons from parent atoms from the limb of Earth's atmosphere “Air” redirects here. For other uses, see Air (disambiguation). Earth's atmosphere is a layer of gases surrounding the planet Earth and retained by the Earth's gravity. It contains roughly (by molar content/volume) 78% nitrogen, 20.95% oxygen, 0.93% argon, 0. to remotely sense vertical profiles of selected atmospheric gases, temperature and pressure. The space MLS experiment is designed to address a broad range of global change issues 1.1 Flight Software Description The MLS flight software consists of three parts: Remote Interface Unit (RIU RIU Regulatory Impact Unit (United Kingdom) RIU Remote Interface Unit RIU Radio Interface Unit RIU Refractive Index Unit RIU Remux Interface Unit RIU Radar/Remote Interface Unit RIU Riverine Interdiction Unit ), Master, and Command and Data Handling (C&DH). Each part is self-contained and operates on a distinct processor within the Instrument. Each software element falls into two further divisions: ROM-based (firmware) and RAM-based. Each of the three software parts will have a part that resides in ROM in the instrument, and each will have an uploadable RAM component. One function of each ROM-based part is the ability to load its corresponding RAM-based software. The RIU is a control node of an onboard serial network that connects the various instrument sensors and actuators to the C&DH. Nominally, the code in each RIU is identical. The RIU is configured for its particular sensor/actuator by command directives to the RIU. The Master is the network controller. It removes the real-time needs of the network from the C&DH. The C&DH software provides communication between the Instrument and the Spacecraft. The principle communication from the Spacecraft to the Instrument consists of commands derived from ground directives that the Spacecraft passes to the Instrument. The Instrument will primarily pass telemetry telemetry Highly automated communications process by which data are collected from instruments located at remote or inaccessible points and transmitted to receiving equipment for measurement, monitoring, display, and recording. data from the sensors to the Spacecraft, which will forward the data to the Ground. The C&DH will also provide primary health maintenance for the Instrument. 1.2 Flight Software Development Phases The software development for the EOS MLS Flight Software represents an approximate 3-year effort at a staffing of three software developers on the average, for that duration. Total Lines of Code The statements and instructions that a programmer writes when creating a program. One line of this "source code" may generate one machine instruction or several depending on the programming language. A line of code in assembly language is typically turned into one machine instruction. (LOC LOC - lines of code ) are expected to be no greater than 10,000. Table 1 summarizes the activities, deliverables and formal reviews associated with each phase of the flight software development life cycle. Activities of subsequent phases may commence before the current phase has been completed. 1.3 IGSE Software Description The MLS IGSE Software consists of three parts: Command and Monitoring, Data Analysis and Level 1 Calibration. The Command and Monitoring software formats, checks and sends command to the MLS instrument ground support equipment and monitors and displays the resulting telemetry. The software also saves the telemetry and controls the command and telemetry databases. The Data Analysis software supports the analysis of the instrument telemetry and supports the analysis of the calibrated cal·i·brate tr.v. cal·i·brat·ed, cal·i·brat·ing, cal·i·brates 1. To check, adjust, or determine by comparison with a standard (the graduations of a quantitative measuring instrument): Level 1B data produced by the Level 1 Calibration software. The Level 1 Calibration software produces the radiometrically calibrated Level 1 B data from the uncalibrated telemetry produced by the instrument. 2. MANAGEMENT APPROACH The MLS software management includes the following specific activities: 1. Product reviews, 2. Configuration management, 3. Quality assurance, 4. Risk management and metrics reporting and 5. Test anomaly management. The software management processes of reviews; configuration management; software product assurance and metrics analysis are part of the risk management program. Defect prevention and early detection is accomplished with the use of peer reviews on software documents and critical program logic, and unit testing (testing) unit testing - The type of testing where a developer (usually the one who wrote the code) proves that a code module (the "unit") meets its requirements. . Technical reviews were conducted in two ways: Peer reviews and formal reviews. The peer reviews will penetrate to a meaningful technical depth, providing direct feedback to the managers involved. The formal reviews will provide the breadth and perspective of a project-level review. The preparation for formal reviews may be abbreviated by drawing upon the results of informal peer reviews. The objectives of peer reviews are to thoroughly look into the technical details in the software documents and to provide direct feedback to the development engineers. 2.1 Software Configuration Management The MLS Flight Software Task and IGSE Task are subject to Configuration Management (CM) controls. Software Configuration Management (SCM (1) (Software Configuration Management, Source Code Management) See configuration management. (2) See supply chain management. ) has these goals: 1. To assign a unique identifier With reference to a given (possibly implicit) set of objects, a unique identifier is any identifier which is guaranteed to be unique among all identifiers used for those objects and for a specific purpose. for each delivered item. 2. To facilitate identification of differences between versions. 3. To facilitate rebuilding of any delivered version. 4. To protect any delivered version from loss due to technical computer failure and mitigate loss due to operational errors 5. To assign to a product version all problem reports, change requests, test variances, and waivers associated with that version. Two other SCM requirements shall be followed: 1. Backup procedures and backup copies of baselined software products shall be maintained in a physically different location from the master copies and 2. Baselined products shall be maintained so that unauthorized access and modifications are prohibited. 2.2 Software Quality Assurance The level of the Software Quality Assurance (SQA SQA Scottish Qualifications Authority SQA Software Quality Assurance SQA Supplier Quality Assurance SQA Society of Quality Assurance SQA Singapore Airlines SQA Sperm Quality Analyzer SQA System Quality Assurance SQA Statistical Quality Analysis ) support will be based on project-criticality. Software Assurance activities consist of the elements listed below (Grady, 1997) 1. Provide concurrent engineering support to the software development teams in the development and documentation of software products and software acceptance test plan and procedures. 2. Provide requirements traceability Overview Traceability as a general term is the "ability to chronologically interrelate the uniquely identifiable entities in a way that matters." The word chronology analysis to insure that all software requirements are properly defined. 3. Monitor software integration activities and provide integration and acceptance test related support as appropriate and within allocated SQA budget constraint A Budget Constraint represents the combinations of goods and services that a consumer can purchase given current prices and his income. Consumer theory uses the concepts of a budget constraint and a preference ordering to analyze consumer choices. . 4. Support fault analysis effort jointly conducted by the Software/Hardware/IGSE to isolate the anomaly to the proper cause generator for problem resolution, and 5. Perform process compliance audit. 3. RISK MANAGEMENT AND METRICS REPORTING The MLS software management approach supports the MLS's risk management of risk avoidance through planning. The software management processes of reviews, configuration management, software quality assurance and metrics analysis are all part of the risk management program. Specific approaches to various risks; metrics data collections, analysis and reporting are described below (Viega and McGraw, 2002) 3.1 Technical Risks The MLS instrument software development adapts the prototyping approach to perform early evaluation of methods and techniques used in the development. Defect prevention and early detection will be accomplished with the use of peer reviews on software documents and critical program logic, and unit testing. Each software requirement in the MLS Instrument Flight Software Requirements Document shall be verified through testing, demonstration, inspection, or analysis. Test planning and designing of the test cases is initiated during the software design phase and into the software implementation phase. 3.2 Security and Safety Risks Virus protection program for software designated for delivery and during storage will be used as needed as needed prn. See prn order. . Software safety risk assessment will be performed as an integral part of the system safety assessment. Analysis techniques such as software Failure Modes and Effects Analysis (FMEA FMEA Fehler-Möglichkeiten & -einfluss Analyse (German: Failure Mode & Effect Analysis) FMEA Failure Modes & Effects Analysis FMEA Florida Music Educators Association FMEA Florida Municipal Electric Association ) and software Fault Tree Analysis (FTA FTA abbr. Future Teachers of America ) will be utilized. 3.3 Resource, Schedule and Cost Risks The software development team will perform the resource, schedule and cost risk assessment and reporting as part of the MLS Project resource, schedule and cost risk management. 3.4 Metrics and Reporting The product metrics for the development of the flight software and IGSE software are maintained in the Project's performance measurement system. The following flight software metrics will be tracked and reported to the project element manager for the Monthly Management Reviews: 1. Completed and current-best-estimate executable source lines of code Source lines of code (SLOC) is a software metric used to measure the size of a software program by counting the number of lines in the text of the program's source code. vs. planned. 2. Actual work months and dollars expended vs. planned. 3. Number and status of external change requests. 4. Number of errors discovered during integration testing and 5. Number of errors discovered during acceptance testing. 4. PRODUCT ACCEPTANCE CRITERIA The criteria for flight software correctness shall be: 1. All success criteria met during Flight Software testing as defined in Flight Software Acceptance Test Plan, and 2. No open problem reports or Problem/Failure Reports (P/FR) remain on Flight Software Set. The criteria for IGSE software correctness shall be 1. All success criteria met during IGSE Software testing as defined in IGSE Acceptance Test Plan, and 2. No open problem reports or (P/FR) remains on IGSE Software Set. 5. CONCLUSION This paper presents the plan for managing and controlling the development of the Microwave Limb Sounder (MLS) instrument software and instrument ground support equipment (IGSE) software. This includes the flight development phases, flight software activities, organization, life cycle, deliverables, and other software development process issues such as configuration management practices, software assurance activities, risk management and metrics reporting.
TABLE 1: FLIGHT SOFTWARE ACTIVITIES IN MLS LIFE CYCLE DEVELOPMENT
Phase Activity Deliverables Rev./Milestone
Software Develop detailed Software SRR: Software
Requirements program requirements Management Requirements
Analysis and Review on (SRD)
Develop key interface Implementation
specifications with Plan
the CDS and with
instrument devices Software
Requirements
Describe command Document (SRD)
definitions and
contents
Produce bit-level
specifications for
input and output
packets
Complete key timing
studies
Determine methodology
for the software
development
Preliminary timing
study
Software Define major data Software Design Software Design
Design structures for the Document (SDD) Review on (SDD)
Analysis Flight Program
Timing study
Define main memo
computational flow
for the Flight
Program
Software Acceptance
Test Plan Finalize
timing stud
Software Produce Command and Software code Internal
Implement. Telemetry Handbook
Phase Command and Incremental
Define memory map for Telemetry
the Flight Computer Handbook Delivery Reviews
Determine all Incremental JPL informal
external interrupts delivery memos peer review:
and device addresses (ATP)
Software
Develop code and Acceptance Test
deliver in Plan (ATP)
incremental
deliveries with Note: unit tests
completed unit tests shall not be
formalized for
Begin work on the MLS Flight
Software Users Guide Software Task.
Develop Software
Acceptance Test
Plan (final)
Software Complete Software Software User (SdeIR):
Acceptance Users Guide Guide Software
Test Phase Delivery Review
Perform acceptance Acceptance Test
testing and correct Report JPL informal
all anomalies peer review:
Tested Software User Guide
Prepare ROM code
for PROM creation Software Release
Description
ACKNOWLEDGMENTS The work described in this paper was carried out at the Jet Propulsion Laboratory “JPL” redirects here. For other uses, see JPL (disambiguation). Jet Propulsion Laboratory (JPL) is a NASA research center located in the cities of Pasadena and La Cañada Flintridge, near Los Angeles, California, USA. , California Institute of Technology California Institute of Technology, at Pasadena, Calif.; originally for men, became coeducational in 1970; founded 1891 as Throop Polytechnic Institute; called Throop College of Technology, 1913–20. , under contract with the National Aeronautics and Space Administration National Aeronautics and Space Administration (NASA), civilian agency of the U.S. federal government with the mission of conducting research and developing operational programs in the areas of space exploration, artificial satellites (see satellite, artificial), (NASA). The authors would like to extend their sincere thanks to anonymous referees and Professor Alan S. Khade for valuable and sincere help. REFERENCES Grady, R.B., Successful Software Process Improvement, Prentice- Hall, New Jersey 1997. Viega, J. and McGraw, G., Building Secure Software Addison Wesley, Reading, MA 2002. Authors Profile: Dr. Joseph S. Sherif she·rif also sha·rif n. 1. A descendant of the prophet Muhammad through his daughter Fatima. 2. The chief magistrate of Mecca in Ottoman times. 3. A Moroccan prince or ruler. earned his Ph.D. at Texas Tech University in 1980. Currently he is a professor of Information Systems and Decision Sciences at California State University, Fullerton California State University, Fullerton, commonly known as CSUF, CSU Fullerton, or Cal State Fullerton, is a part of the California State University system. The University is located in the city of Fullerton, California, in northern Orange County. . Hui-Yin Shaw earned her BS and MS at UCLA UCLA University of California at Los Angeles UCLA University Center for Learning Assistance (Illinois State University) UCLA University of Carrollton, TX and Lower Addison, TX in 1980. Currently she is a manager at the Jet Propulsion Laboratory of California Institute of Technology, Pasadena. Joseph S. Sherif, California State University-Fullerton, California, USA Hui-Yin Shaw, California Institute of Technology-Pasadena, California, USA |
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