Search

We put forward a use-case based approach for SRML – a formal framework that is being defined by the SENSORIA consortium for service-oriented modelling. We expand on the way SRML contributes to the engineering of software systems and we propose a number of extensions to the UML for supporting that approach. We use a mortgage brokerage scenario for illustrating our approach.

We develop an abstract operational model for configuration management under service-oriented computing. This semantics is based on a graph-based representation of the configuration of global computers and an operational model of service-oriented dynamic reconfiguration based on a resolution-like mechanism similar to concurrent constraint programming. A resolution step involves a goal executed by a business activity and a clause that corresponds to a complex service. Unification captures service discovery, ranking and selection based on SLA-constraint optimisation and interpretations between specifications of conversations expected by the goal and provided by the discovered service. The resolvent is a reconfiguration of the original business activity that results from binding the goal with the discovered service.

First page of article Keywords: space technology 5 (ST5) mission; communications components for small spacecraft

The International Space Station (ISS) currently provides human waste collection and hygiene facilities in the Russian Segment Service Module (SM) which supports a three person crew. Additional hardware is planned for the United States Operational Segment (USOS) to support expansion of the crew to six person capability. The additional hardware will be integrated in an ISS standard equipment rack structure that was planned to be installed in the Node 3 element; however, the ISS Program Office recently directed implementation of the rack, or Waste and Hygiene Compartment (WHC), into the U.S. Laboratory element to provide early operational capability. In this configuration, preserved urine from the WHC waste collection system can be processed by the Urine Processor Assembly (UPA) in either the U.S. Lab or Node 3 to recover water for crew consumption or oxygen production. The human waste collection hardware is derived from the Service Module system and is provided by RSC-Energia. This paper describes the concepts, design, and integration of the WHC waste collection hardware into the USOS including integration with U.S. Lab and Node 3 systems.

High precision attitude control is vital to achieve safe and reliable operation of crew exploration vehicles (CEVs) such as docking (with service module) and landing (on the moon or earth). This work investigates a robust adaptive approach to adjusting CEV's orientation through the driving forces produced by various RCS engines mounted on the vehicle. By using the structural properties of the capsule vehicle and the 4-parameter (quaternion) orientation representation, a set of control algorithms are developed to ensure adaptive and robust attitude tracking of CEV. The proposed control scheme explicitly addresses 1) uncertain aerodynamics due to unpredictable disturbances; 2) time-varying and uncertain mass property of the vehicle due to fuel consumption, payload release, and/or modules separation; and 3) guaranteed tracking performance under varying operation conditions. It is shown that the developed control scheme does not demand detail vehicle system parameters/dynamics and asymptotic orientation tracking is achieved. Furthermore, tracking performance index is guaranteed bounded and there is no need to redesign or reprogram the control scheme under varying flight/operation conditions. Both theoretic analysis and simulation studies confirm the effectiveness of the proposed method.

The analysis of candidate thruster configurations for the Crew Exploration Vehicle (CEV) is presented. Six candidate configurations were considered for the prime contractor baseline design. The analysis included analytical assessments of control authority, control precision, efficiency and robustness, as well as simulation assessments of control performance. The principles used in the analytic assessments of controllability, robustness and fuel performance are covered and results provided for the configurations assessed. Simulation analysis was conducted using a pulse width modulated, 6 DOF reaction system control law with a simplex-based thruster selection algorithm. Control laws were automatically derived from hardware configuration parameters including thruster locations, directions, magnitude and specific impulse, as well as vehicle mass properties. This parameterized controller allowed rapid assessment of multiple candidate layouts. Simulation results are presented for final phase rendezvous and docking, as well as low lunar orbit attitude hold. Finally, on-going analysis to consider alternate Service Module designs and to assess the pilot-ability of the baseline design are discussed to provide a status of orbit control design work to date.

The Orion Spacecraft will be required to perform entry and landing functions for both Low Earth Orbit (LEO) and Lunar return missions, utilizing only the Command Module (CM) with its unique systems and GN&C design. This paper presents the current CM Flight Control System (FCS) design to support entry and landing, with a focus on analyses that have supported its development to date. The CM FCS will have to provide for spacecraft stability and control while following guidance or manual commands during exo-atmospheric flight, after Service Module separation, translational powered flight required of the CM, atmospheric flight supporting both direct entry and skip trajectories down to drogue chute deploy, and during roll attitude reorientation just prior to touchdown. Various studies and analyses have been performed or are on-going supporting an overall FCS design with reasonably sized Reaction Control System (RCS) jets, that minimizes fuel usage, that provides appropriate command following but with reasonable stability and control margin. Results from these efforts to date are included, with particular attention on design issues that have emerged, such as the struggle to accommodate sub-sonic pitch and yaw control without using excessively large jets that could have a detrimental impact on vehicle weight. Apollo, with a similar shape, struggled with this issue as well. Outstanding CM FCS related design and analysis issues, planned for future effort, are also briefly be discussed.

The Constellation Environmental Impact Statement (Cx EIS) requires that an assessment be performed on the environmental impact of sonic booms during the reentry of the Crew Exploration Vehicle (CEV). This included an analysis of current planned vehicle trajectories for the Crew Module (CM) and the Service Module (SM) debris and the determination of the potential impact to the overflown environment.

The Orion Crew Exploration Vehicle is the first crewed capsule design to be developed by NASA since Project Apollo. Unlike Apollo, however, the CEV is being designed for service in both Lunar and International Space Station missions. Ascent aborts pose some issues that were not present for Apollo, due to its launch azimuth, nor Space Shuttle, due to its cross range capability. The requirement that a North Atlantic splashdown following an abort be avoidable, in conjunction with the requirement for overlapping abort modes to maximize crew survivability, drives the thrust level of the service module main engine. This paper summarizes 3DOF analysis conducted by NASA to aid in the determination of the appropriate propulsion system for the service module, and the appropriate propellant loading for ISS missions such that crew survivability is maximized.

The Crew Exploration Vehicle (CEV) is required to maintain continuous abort capability from lift off through destination arrival. This requirement is driven by the desire to provide the capability to safely return the crew to Earth after failure scenarios during the various phases of the mission. This paper addresses abort trajectory design considerations, concept of operations and guidance algorithm prototypes for the portion of the ascent trajectory following nominal jettison of the Launch Abort System (LAS) until safe orbit insertion. Factors such as abort system performance, crew load limits, natural environments, crew recovery, and vehicle element disposal were investigated to determine how to achieve continuous vehicle abort capability.

The Spacecraft Imbedded Distributed Error Response (SPIDER) Fault Protection architecture used on the Mars Reconnaissance Orbiter (MRO) incrementally developed capabilities based upon heritage spacecraft. The primary driving factors behind the improvements for this mission stemmed from several key concerns and development goals/requirements. Due to decreased risk tolerance at the program level, most hardware was cross-strapped on the spacecraft and additional autonomous responses were required to ensure the safety of the spacecraft to provide for a more robust handling of the system during high-risk events. Numerous interplanetary spacecraft missions have demonstrated the need to reduce maintenance effort during spacecraft operations. Aerobraking: the process of using atmospheric drag to dissipate orbital energy to achieve the desired science orbit following orbit insertion is a delicate process. The operations team is constrained by orbit geometry, 2-way light time delays, Martian weather, and a highly dynamic environment in which each pass through the atmosphere affects the subsequent orbit timing in a non-deterministic way. In the event of a fault on past missions, the operations team has required both constant contact with the spacecraft to diagnose the failure, and prompt issuance of the necessary ground commands to ensure spacecraft safety. In order to increase the autonomous response capability during Aerobraking and reduce the response time to faults, MRO developed a new set of capabilities, called the Navigation Performance Monitor (NPM). NPM, a member of the performance layer of SPIDER Fault Protection software, provides autonomous orbit domain modeling so the spacecraft may configure itself correctly for events within each orbit. During Aerobraking for MRO, NPM was called into action and successfully provided orbit modeling data to the Safe Mode software in response to two system faults; this demonstrated the robustness of our approach.

The Altcriss project was submitted in response to ESA AO-2004. It was approved in March 2005 and begun in December 2005 with Progress 21-P launch from Baikonur. It is currently operating on board the International Space Station, performing a survey of the radiation environment and the effectiveness of shielding materials from cosmic rays. It uses the active silicon detector Sileye-3 and a series of passive dosimeters (CR-39, TLD). The detectors have currently been operational in different location of the Pirs (docking) and Service module of the Russian section of the Station. The project is expected to continue up to 2008.

During graduation design, the quality of the final dissertation is connected with the appropriate reference reading. Therefore, the tutors should cost a great deal of time to choose reference for the students' research. The paper trial used to carry out the reference auto recommendation model within a graduation design intelligent tutor system according to the personalized recommendation technique which based on the user characteristic; it assisted to the teacher's reference offer work availably. Though the test use, it preferably completed the auto recommendation of the student reference weekly, and the satisfaction of the teachers' and the students' is high.

The Gravity Probe B spacecraft, developed, integrated, and tested by Lockheed Missiles & Space Company and later Lockheed Martin Corporation, consisted of structures, mechanisms, command and data handling, attitude and translation control, electrical power, thermal control, flight software, and communications. When integrated with the payload elements, the integrated system became the space vehicle. Key requirements shaping the design of the spacecraft were: (1) the tight mission timeline (17 months, 9 days of on-orbit operation), (2) precise attitude and translational control, (3) thermal protection of science hardware, (4) minimizing aerodynamic, magnetic, and eddy current effects, and (5) the need to provide a robust, low risk spacecraft. The spacecraft met all mission requirements, as demonstrated by dewar lifetime meeting specification, positive power and thermal margins, precision attitude control and drag-free performance, reliable communications, and the collection of more than 97% of the available science data.

Issuance of disparate identifiers to students, manual method of student identity management and access control and the unavailability of actionable information on pattern of students’ use of schools’ services describe identity and access management in tertiary institutions in developing countries. An Integrated Identity and Access Management System for tertiary institutions is developed in this work. This Tertiary Identity and Access Management System (T-IAMS) is a fingerprint biometric database that centrally manages students’ identity, course registration, library and medical services information. It shortens student provisioning and de-provisioning processes, provides medical service data mining functionality and offers examination screening module which checks students into examination centres by cross-referencing database enrolment with course registration status. The system was developed following exploratory type of evolutionary software development model. MySql was used in building the database and Visual Basic for developing the graphic user interface of the student record module. The work also reports the results of testing done by 20 testers, on a 5-point scale. Analysis of the test results shows the system’s average acceptability percentage of 100 in ability to prevent duplicate enrolments, 79.165 in effectiveness in student clearance while the format and usefulness of reports generated on the medical service module recorded 73.125 as average acceptability percentage. Also, effectiveness in examination screening averaged 66.785 in performance acceptability. It has been shown that managing student identity centrally eases student provisioning and de-provisioning processes, and tightens access control to school facilities and programmes. http://dx.doi.org/10.4314/njt.v34i4.23

Background Patient empowerment integrates multiple concepts that allow a patient to effectively self-manage his disease, which are accessing to health information, education, bi-directional communication between patients and healthcare professionals, self-care support, chronic disease management support and shared decision making. Objectives To evaluate whether an online personal health platform improves AS patients9 health and enhances their effectiveness in managing their health. Methods Within the scope of European Commission supported PALANTE project [1], an online personal health platform is developed for AS patients in Turkey. The platform consists of two main modules: Personal Health Records and Virtual Arthritis Clinical Service. Personal Health Records module allows patients to access their basic health records like allergies, problems, medications, immunizations, lab results etc., which are retrieved from Turkish National Health Information System, namely SaglikNet2. Virtual Arthritis Clinical Service module contains AS disease specific sub modules, some of which are: diary module which allows patients to record their daily status like morning pains etc. and share them with healthcare professionals, messaging module which allows patients to ask questions to their healthcare professionals whenever they want and without getting any appointment, exercise module which allows patients to follow the exercise plan specified by physical therapist, videos module which allows patients to learn how to do exercises correctly. The developed system has been used by 131 patients and 3 healthcare professionals in Turkey. In order to evaluate the success of the system, a questionnaire was sent to the patients after they used the system for 6 months. Results Questions are categorized in three groups as communication features, educational features, and informational features. For each group, same set of questions were asked to patients. 70 patients conducted the questionnaire and following responses are retrieved. Conclusions As it can be seen from the table above, majority of patients reacted positively and want the services to continue. Patients found educational features, which contains videos module that allows patients to do their daily exercises correctly without consulting physical therapist, as the most useful functionality of the system. Furthermore, patients mostly want communication features, which provide direct communication between patients and healthcare professionals, to continue. As a result, an online personal health platform improved AS patients9 health and enhanced their effectiveness in managing their health. References http://palante-project.eu/ Acknowledgements The work presented in this paper is achieved in the scope of PALANTE project [1] supported by the European Community9s Seventh Framework Programme (FP7/2007-2013) under grant agreement number 297260. Disclosure of Interest None declared

ROKVISS, Germany’s newest space robotics technology experiment, was successfully installed outside at the Russian Service Module of the International Space Station (ISS) during an extravehicular space walk at the end of January 2005. Since February 2005 a two joint manipulator is operated from ground via a direct radio link. The aim of ROKVISS is the in flight verification of highly integrated modular robotic joints as well as the demonstration of different control modes, reaching from high system autonomy to force feedback teleoperation (telepresence mode). The experiment will be operated for at least one year in free space to evaluate and qualify intelligent light weight robotics components under realistic circumstances for maintenance and repair tasks as foreseen in upcoming manned and unmanned space applications in near future. This paper focuses in the telepresence control mode, its technology and first results from the space experiment ROKVISS.

System analysis is an essential technical discipline for the modern design of spacecraft and their associated missions. Specifically, system analysis is a powerful aid in identifying and prioritizing the required technologies needed for mission and/or vehicle development efforts. Maturation of intelligent systems technologies, and their incorporation into spacecraft systems, are dictating the development of new analysis tools, and incorporation of such tools into existing system analysis methodologies, in order to fully capture the trade-offs of autonomy on vehicle and mission success. A "system analysis of autonomy" methodology will be outlined and applied to a set of notional human-rated lunar/Mars lander missions toward answering these questions: 1. what is the optimum level of vehicle autonomy and intelligence required? and 2. what are the specific attributes of an autonomous system implementation essential for a given surface lander mission/application in order to maximize mission success? Future human-rated lunar/Mars landers, though nominally under the control of their crew, will, nonetheless, be highly automated systems. These automated systems will range from mission/flight control functions, to vehicle health monitoring and prognostication, to life-support and other "housekeeping" functions. The optimum degree of autonomy afforded to these spacecraft systems/functions has profound implications from an exploration system architecture standpoint.

The NASA Exploration Systems Architecture Study (ESAS) produced a transportation architecture for returning humans to the moon affordably and safely, while using commercial services for tasks such as cargo delivery to low earth orbit (LEO). Another potential utilization of commercial services is the delivery of cryogenic propellants to LEO for use in lunar exploration activities. With in-space propellant resupply available, there is the potential to increase the payload that can be put on the moon, increase lunar mission durations, and enable a wider range of lunar missions. The availability of on-orbit cryogenic propellants, either at a propellant depot or directly from a propellant transfer stage, would impact the sizing and reusability of many architecture elements, including the Earth Departure Stage (EDS), the Crew Launch Vehicle (CLV) upper stage, the Lunar Surface Access Module (LSAM), and the Service Module (SM). These vehicles are modeled to approximate the baseline established by ESAS. Methods and tools used include launch trajectory optimization with POST, vehicle aerodynamic analysis using APAS, weights and sizing using historical and physics based estimating relationships, and cost estimation using NAFCOM. Uncertainty in estimates of advanced technology performance is modeled using probabilistic methods, such as Monte Carlo simulation. The impact of propellant resupply capability on vehicle design and performance is investigated. The availability of propellant at LEO allows for many possible architecture changes, including increasing the payload delivered to the moon, decreasing the size of the heavy lift launch vehicle, or staging extra propellant in lunar orbit. Other elements could also be designed to be reusable with propellant resupply available, such as the LSAM, the CLV upper stage, and the Service Module. Several of these architecture changes are investigated, and compared via metrics such as mission reliability, cost, and the range of lunar and near-Earth mission capabilities (i.e. duration time, mission latitude, missions to Lagrange points) they allow.

After separation from the launch vehicle, a spacecraft's guidance and control system typically orients the spacecraft autonomously into a three-axis stabilized attitude for non-spinners. If an anomaly occurs, or if the spacecraft fails to orient itself appropriately, the Mission Operations team will want to observe spacecraft telemetry or may even be required to command the spacecraft before attitude stabilization. Antenna coverage in these cases is critical, since the command and control antenna may be rotating away from the ground station line-of-sight as the spacecraft tumbles. However, activating opposite-pointing hemispherical low-gain antennas on the spacecraft to obtain more complete angular coverage comes at the cost of presenting an interferometric signal to the ground station (or spacecraft receiver, depending on the radio-frequency subsystem configuration) which fluctuates as a function of the relative antenna positions and tumble rate of the spacecraft. Recent programs developed by The Johns Hopkins University Applied Physics Laboratory, specifically MESSENGER and STEREO, have investigated the capability of the deep space network and universal space network receivers to recover telemetry from a tumbling spacecraft at a low orbital altitude. Also investigated was the ability of a tumbling spacecraft utilizing a small deep-space transponder to register valid uplink commands, even in the presence of a second, closely-spaced uplink frequency, as expected for the two STEREO spacecraft.

ROKVISS, the German new space robotics technology experiment, was successfully installed outside at the Russian Service Module of the International Space Station (ISS) during an extravehicular space walk at the end of January 2005. Since February 2005 a two joint manipulator can be operated from ground via a direct radio link. The aim of ROKVISS is the in flight verification of highly integrated modular robotic joints as well as the demonstration of different control modes, reaching from high system autonomy to force feedback teleoperation. A main goal of the experiment is the evaluation of the dynamical parameters (especially friction, motor constant and stiffness), as well as the monitoring of their evolution over the duration of the mission, in order to validate the long term performance of the system. The paper gives first a short overview of the experiment and in particular a description of the applied control structures. The main focus of the paper is on the joint parameter identification results obtained so far, during one year of operation

Power systems with voltages higher than about 55 volts may charge in Low Earth Orbit (LEO) enough to cause destructive arcing. The NASA STD-4005 LEO Spacecraft Charging Design Standard will help spacecraft designers prevent arcing and other deleterious effects on LEO spacecraft. The Appendices, an Information Handbook based on the popular LEO Spacecraft Charging Design Guidelines by Ferguson and Hillard, serve as a useful explanation and accompaniment to the Standard.

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched on August 3, 2004, is a NASA spacecraft that will orbit the planet Mercury for a one-year mission. The spacecraft launch mass limitation, combined with the large solar distance variations, impose severe requirements on the spacecraft power and thermal subsystems. The spacecraft is three-axis stabilized. A sunshade protects the spacecraft from the high intensity solar flux. The attitude control maintains the sunshade pointed to the Sun. The solar panels, which are outside the thermal shield, are designed to survive normal Sun incidence at 0.3 AU. The solar panels consist of alternating rows of triple junction cells placed between Optical Solar Reflectors (OSRs). Solar panels thermal control is performed by tilting the panels with increasing solar flux. To minimize the mass of the spacecraft, the structure is made of composite materials. Spacecraft electronic boxes that are high power dissipaters are designed with special thermal vias that conduct the heat directly to diode heat pipes, which transport the heat of the box to thermal radiator panels on the side of the spacecraft behind the sunshade. The MESSENGER spacecraft is on a trajectory to enter Mercury orbit in 2011. The spacecraft is performing as designed.

A two-year task sponsored by NASA's Mars Technology Program's Advanced Entry, Descent and Landing (EDL) work area includes investigation of improvements to EDL navigation by processing spacecraft-to-spacecraft radiometric data. Spacecraft-to-spacecraft navigation will take advantage of the UHF link between two spacecraft (i.e. to an orbiter from an approaching lander for EDL telemetry relay) to build radiometric data, specifically the velocity between the two spacecraft along the radio beam, that are processed to determine position and velocity in real time. The improved onboard state knowledge provided by spacecraft-to-spacecraft navigation will improve the performance of entry guidance by providing a more accurate state estimate and ultimately reduce the landed position error. A previous paper documented the progress of the first year of this task, including the spacecraft definitions, selection and documentation of the required algorithms and analysis results used to define the algorithm set. The final year of this task is reported here. Topics include modifications to the previously selected algorithm set for implementation, and performance of the implemented algorithms in a stand-alone filter, on an emulator of the target processor and finally on a breadboard processing unit.

A study is performed to ascertain the validity of the use of inviscid and viscous simulation methods to predict the axial and normal forces during a launch abort scenario for manned space flight vehicles. The proximity drag character of the Apollo launch escape vehicle (LEV) was studied in detail in a wind tunnel during the Apollo program. Simulation results obtained during the present effort are compared to the Apollo era wind tunnel experiments. The validated simulation techniques are applied to assess the possibility of recontact between the crew capsule and the service module after a launch abort is initiated. The natural extension of the method is to assess the risk associated with the new Crew Launch Vehicle’s escape system.

A distributed problem solving environment (PSE) is proposed to help users solve partial differential equation (PDE) based problems in scientific computing. The system inputs a problem description and outputs a program flow, a C-language source code for the problem and also a document for the program. Each module is distributed on distributed computers. The PSE contains all the information of the problem, PDEs, discretization scheme, mesh information, equation manipulation results, designed program structure, variable and constant definitions and program itself. Therefore the documentation support module generates a document for the generated program and the problem itself in the PSE. The module liaison module generates an adapter module among the distributed PSE modules. The job execution service module deploys programs generated or prepared on distributed computer resources and helps users run the programs on the distributed computers. The concept of the distributed PSE extends the potential of conventional PSE systems

The Service Module (SM) is an element of the Russian Segment of the International Space Station (ISS). One of the functions of the SM is to provide attitude control for the ISS using thrusters when the U.S. Control Moment Gyros (CMG's) must be desaturated. Prior to an Extravehicular Activity (EVA) on the Russian Segment, the Docking Compartment (DC1) is depressurized, as it is used as an airlock. When the DC1 is depressurized, the CMG's margin of momentum is insufficient and the SM attitude control thrusters need to fire to desaturate the CMG's. SM roll thruster firings induce contamination onto adjacent surfaces with Fuel Oxidizer Reaction Products (FORP). FORP is composed of both volatile and non-volatile components. One of the components of FORP is the potent carcinogen N-nitrosdimethylamine (NDMA). Since the EVA crewmembers often enter the area surrounding the thrusters for tasks on the aft end of the SM and when translating to other areas of the Russian Segment, the presence of FORP is a concern. This paper will discuss FORP contamination of the SM surfaces, the release of NDMA in a humid environment from crew EVA suits, if they happen to be contaminated with FORP, and the toxicological risk associated with the NDMA release.

This paper describes the main characteristics of the latest medium-sized mission launched by ESA as part of its science programme. An overview of the telescope and cryogenic system is given.

Gaia is the most ambitious space astrometry mission currently envisaged and is a technological challenge in all its aspects. We describe a proposal for the payload data handling system of Gaia, as an example of a high-performance, real-time, concurrent, and pipelined data system. This proposal includes the front-end systems for the instrumentation, the data acquisition and management modules, the star data processing modules, and the payload data handling unit. We also review other payload and service module elements and we illustrate a data flux proposal.

IEC61850 series defines the abstract data model and service model in an object-oriented method, and also the mapping to specified protocols such as MMS and etc. This paper analyzes four kinds of data structure while implementing IEC61850. The paper compares the capability of supporting the service module of IEC61850 in these four data structure,which considers that Comprehensive-Data-Structure not only is according with the protocol mapping now but also supporting the changes of future model and the extension of protocol mapping. It has a better life-force as to be recommended to use. (6 pages)

Atmospheric re-entry module is a part of a spacecraft, which is separated from the spacecraft, de-orbits, re-enters into the Earth atmosphere, and descents to the Earth surface. In this paper, 3-DOF flight trajectory of a small re-entry module is simulated to design its separation position and Earth landing point. The estimation of the landing position is important the safety and recover reason. The configuration of the re-entry module is assumed to be compatible with the STSAT series spacecraft. Various models, such as atmosphere, gravitation, and flight dynamics are applied to simulate the re-entry module trajectory under the design-to assumptions of re-entry module propulsion and attitude control performances.

In order to explore the deep space, such as Mars, Jupiter, Saturn, etc in the future, a spacecraft that will be driven by nuclear power should be developed.

This paper addresses the product design and realization processes in distributed manufacturing environments. It presents the Web-based integration methodology and framework to support collaborative and concurrent engineering (CE) design. The distributed CE and collaboration are discussed as key components in the collaborative mechanism. In detail, it integrates four functional modules including co-design, Web-based visualization, manufacturing analysis and service module. In realization, Java-based and Internet-enabled technologies can support extended strategies for design and planning. The related system can be used for a design team geographically distributed to organize a collaborative and CE design effectively

The upcoming 3rd generation mobile communications system UMTS/IMT-2000 will provide high data rates and advanced means for service generation. In conjunction with so-called smart phones a cass of entirely new services, exploiting mobility and multimedia will become possible.

Flight operations at the Jet Propulsion Laboratory (JPL) are now performed by teams of specialists, each team dedicated to a particular spacecraft. Certain members of each team are responsible for monitoring the performance of their respective spacecraft subsystems. Ground operations are manual, labor-intensive, and tedious. The challenge of the new decade is to operate a large number of spacecraft simultaneously, while sharing limited human and computer resources without compromising overall reliability. The Engineering Analysis Subsystem Environment (EASE) is being developed to enable fewer controllers to monitor and control power and other spacecraft engineering subsystems. An early version of the EASE prototype has been installed in the JPL Space Flight Operations Facility for on-line testing. This paper discusses the underlying concept, development, testing of the EASE prototype, and how it will aid in the ground operations of spacecraft power subsystems.

SOHO, the European Space Agency (ESA) solar observation satellite, has experienced a large number of single event effects (SEEs) since its launch in December 1995. This paper details events believed to be induced by cosmic rays or protons. Self-switch-off power supply events in the service module and in the payload module will be detailed as well as single event upsets (SEUs) in the solid-state recorder (SSR) and in the global oscillation at low frequency (GOLF) instrument. Power system events are believed to originate from transient SEUs in linear components. SSR and GOLF SEUs are seen to respond to solar particle events. Relevant ground verification testing will be presented and upset predictions are compared with observations.

Historically, human-rated spacecraft, such as Mercury, Gemini, Apollo, Skylab, ApolloSoyuz Test Program (ASTP), Space Shuttle and the International Space Station (ISS) programs, have been designed and constructed for mission-specific goals and objectives. It has only been recently that considerations were given to improve crew radiation shielding and exposure protection. An example is the shielding augmentation plan that was utilized for the ISS in which high-density polyethylene (HDPE) was used to line the sleep quarters in the Russian Service Module to lessen crew radiation exposures. With the pending retirement of the Space Shuttle and the design and development of its replacement, the Crew Exploration Vehicle, it is imperative that the spacecraft designers work closely with the radiation physicists to incorporate the necessary crew radiation shielding to adhere to the ALARA (“As Low As Reasonably Achievable”) principle at the design outset. In this paper, a review of the space radiation environment, crew radiation exposures (flight measurements), and spacecraft design considerations for human radiation shielding and protection are presented and discussed in detail. Concepts other than materials are also briefly discussed. These design considerations can be extended and applied to other human space enclosures and habitats.

The MESSENGER spacecraft, the first mission to the planet Mercury since 1975, will achieve Mercury orbit in 2011. The spacecraft uses two opposite-facing mission-enabling X-band (8.4 GHz) phased-array antennas to achieve high-rate downlink communications. The spacecraft orientation is constrained such that a preferred direction faces the Sun; rotation about the Sun-line is allowable. The main beam of each antenna is steerable in one dimension. These two degrees of freedom allow the main beam of the phased array to be pointed in any direction about the spacecraft. A novel system-level design requires many different subsystems of the spacecraft to interact together to achieve accurate beam-pointing, and thus, high-rate downlink data from Mercury to Earth

In the ocean dynamical environment real-time stereo monitoring system of Taiwan Strait and adjacent maritime region, multiple monitoring data such as remote sensing data, structured data will be produced by the stereo monitoring net from airspace, ocean surface, underwater space and ocean bottom. The information service system is a key part to influence the application efficiency of the whole system. According to the characteristics of the oceanic dynamical environment of Taiwan Strait, the construction scheme of the stereo monitoring net is introduced in this paper firstly. The stereo monitoring net will integrate the advanced study achievement on oceanic dynamic environment monitoring technology of our country. Then the architecture of the monitoring data sharing and service system is introduced, which includes five parts, i.e. the monitoring data acquiring module, the data integration module, the data processing and information production development module, and the information sharing and service module. Next, the user classification system and service content classification are introduced. The users are divided into five classes and the service content is divided into 4 layers. At last, the technology realization strategy is introduced. The technology includes the C/S architecture based data analysis and service, and the B/S architecture based online Web analysis and service