The Advanced Mission Computer and Display system for naval aviation

Safety critical systems, such as aviation systems controlled by software, often have hard real-time requirements. Producing the correct result at the right time is the fundamental goal of such systems. Formally specifying the system functions and the timing requirements is the crucial step towards achieving such a goal. Aviation systems often need to be modified or upgraded on a regular basis, i.e. functionality and timing constraints may be altered. Therefore, the formal specification of such systems needs to be easily reused, maintained and modified. This paper demonstrates how the task scheduling aspects of an aircraft mission computer can be formalised in TCOZ.

In 1995, an initiative was launched to assess the potential for reuse of operational flight program software across multiple fighter aircraft platforms, and to define and demonstrate a supporting system architecture based upon open commercial hardware, software, standards and practices. This initiative produced a set of reusable object oriented navigation software, which was flight tested on several different aircraft platforms hosted on different hardware configurations. The following year, this validation of the product line approach led to broader application of the techniques to the tactical aircraft mission processing domain. Key aspects of the component based logical architecture developed have been previously described. This paper traces the process used to develop the Software Architecture used for this project.

Attempts to improve the reliability and maintainability of Special Operations Forces (SOF) fixed wing aircraft avionics by developing the mission computer replacement prototype (MCRP), are described. The purpose of the MCRP is to design, build, and demonstrate a replacement mission computer that is applicable across SOF aircraft. Our goal is to develop an open architecture mission computer based on industry standards and COTS and nondevelopmental item components, with maximum reuse of the existing operational flight program software.

Pairwise alignment of protein structures is a fundamental task in structural bioinformatics. There are numerous computer programs in the public domain that produce alignments for a given pair of protein structures, but the results obtained by the various programs generally differ substantially. Hence, in the application of such programs the question arises which of the alignment programs are the most trustworthy in the sense of overall performance, and which programs provide the best result for a given pair of proteins. The major problem in comparing, evaluating and judging alignment results is that there is no clear notion of the optimality of an alignment. As a consequence, the numeric criteria and scores reported by the individual structure alignment programs are largely incomparable. Here we report on the development and application of a new approach for the evaluation of structure alignment results. The method uses the translation vector and rotation matrix to generate the superposition of two structures but discards the alignment reported by the individual programs. The optimal alignment is then generated in standardized form based on a suitably implemented dynamic programming algorithm where the length of the alignment is the single most informative parameter. We demonstrate that some of the most popular programs in protein structure research differ considerably in their overall performance. In particular, each of the programs investigated here produced in at least in one case the best and the worst alignment compared with all others. Hence, at the current state of development of structure comparison techniques, it is advisable to use several programs in parallel and to choose the optimal alignment in the way reported here. The computer software that implement the method described here is freely available at http://melolab.org/stovca.

Mobile healthcare systems are currently considered as key research areas in the domain of software engineering. The adoption of modern technologies, for mobile healthcare systems, is a quick option for industry professionals. Software architecture is a key feature that contributes towards a software product, solution, or services. Software architecture helps in better communication, documentation of design decisions, risks identification, basis for reusability, scalability, scheduling, and reduced maintenance cost and lastly it helps to avoid software failures. Hence, in order to solve the abovementioned issues in mobile healthcare, the software architecture is integrated with personal software process. Personal software process has been applied successfully but it is unable to address the issues related to architectural design and evaluation capabilities. Hence, a new technique architecture augmented personal process is presented in order to enhance the quality of the mobile healthcare systems through the use of architectural design with integration of personal software process. The proposed process was validated by case studies. It was found that the proposed process helped in reducing the overall costs and effort. Moreover, an improved architectural design helped in development of high quality mobile healthcare system.

Moving toward the third-generation (3G), wireless service providers (WSPs) have key decisions to make in evolving their backbone networks in a cost-effective way. Today, most WSPs in the United States deploy fully meshed, circuit-switched metro backbone networks and hand off long-distance traffic to an interexchange carrier (IXC). With the increased complexity of managing a growing meshed network and the emergence of enhanced data services, the goal is to evolve toward a multi-service packet network. This paper presents a rigorous model for circuit-to-packet (C2P) network evolution planning that addresses evolution alternatives for voice services, technology choice, network architectures, design, performance, reliability, and financial analysis. The model allows WSPs to quantify the benefits of various evolution scenarios and helps Lucent Mobility Solutions assess product roadmaps. The paper also presents a case study based on typical code division multiple access (CDMA) WSPs in North America that examines various C2P evolution strategies in metro, regional, and national backbones based on different choices of technology (TDM vs. ATM vs. IP), product availability, network architectures, and traffic forecasts. Also included are key insights and a summary of the study results.

This special issue is based on a collection of selected papers presented at the Fifth International Conference on Advanced Computing held in Chennai (Madras), India in December 97. The International Conference on Advanced Computing is organized annually in India by the Advanced Computing Society (ACS) which is a premier professional society set up in India to cater to the broad interests in the area of Advanced Computing. One of the significant activities of the Society is to organize regular Meetings/Conferences/Symposia. The Conferences are held annually in India during December. Out of the shortlisted papers presented at the Conference held in Chennai (Madras) during December 97, the following six papers were finally selected after a second round of detailed review of the papers. The first paper On designing and implementing collaborative system using Java-RMI by Rajeev R. Raje, Snehasis Mukhopadhyay, Michael Boyles and Nila Patel describe the use of Java-RMI in designing a collaborative information classifier. The principles of RMI, the details of the prototype, and some preliminary results are presented. The paper primarily concentrates on web-based computing paradigms. In the second paper A framework for performance-based program partitioning , Ram Subramanian and Santosh Pande present an efficient and accurate performance model based program-partitioning approach for parallel architectures. The interactions between computation and communication are captured through behavioral edges . The approach yields significant performance improvement. The third paper DDSCHED: a distributed dynamic real-time scheduling algorithm by Anup K. Bhattacharjee, K. Ravindranath, R. Mall and A. Pal presents a dynamic soft real-time scheduling algorithm for distributed systems. The algorithm is based on a local scheduler and a distributed scheduling scheme. The algorithm takes care of the network delays assuming that the communication protocol is CSMA/CD. In the fourth paper Generic operational decomposition for concurrent systems semantics and reflection , Annie Marcoux, Christine Maurel, Frederic Migeon and Patrick Salle discuss about the reflection in concurrent languages, particularly in actor-based languages. The main objective of the paper is to extend concurrent systems to reflection. The authors present a modular and dynamic description of entity operational management, and extend the decomposition to obtain reflective entities. The fifth paper Parallel programming using visual patterns by A. S. M. Sajeev proposes a two level approach to parallel programming within the context of a visual environment. The first level is the specification of patterns encapsulating process communation and synchronization, and the second level is the use of patterns for parallel programming. The approach encourages reuse of patterns. In the sixth paper An application framework for dynamic distributed software architectures , G. R. Ribeiro-Justo and P. R. F. Cunha present an object-oriented application framework for developing evolving (reconfigurable) software architectures for distributed systems. The application framework is called C++CL. Such a requirement is encountered in banking, industrial control and telecommunications applications. We are extremely thankful to the following reviewers who have helped us in reviewing the papers submitted for this special issue: Lawrence Jenkins N. Mohan Ram Nishit Narang Rajeev Shorey Sameer Adhikari K. Balaji K. Rajan Sumit Kasera Subhrajyothi Bhar Pankaj Sethi Ravindranath Kokku Guest Editors: L. M. Patnaik, Ravi Mittal and K. M. Mehta

Introduction: The introduction of Clinical Information Systems (CIS) to manage and store patient information has deeply modified the workflow of caregivers. As the information is no longer stored on a physical medium, caregivers depend on the presence of a computer to access patient data. This constraint has built up an invisible barrier between the source of information and the place of its use. The popularisation of mobile devices offers an oportunity to break this barrier by providing a ubiquitous access to information. The use of a mobile platform merges the advantages of a modern CIS and the mobility offered by paper. We have developed an application on a mobile device that nurses can carry along on all their visits. It allows the information gathered during their visits to be entered directly into the system. Method: The tool we present aims to manage the daily interventions of nurses. The interventions concern all kinds of treatments provided by nurses to patients. In the current organisation, nurses start their day by printing out all the daily interventions and use it as a procedure to follow. Every time a nurse performs an intervention, she takes a note indicating that the task has been done properly. When they have some spare time, nurses enter all the gathered information in the CIS. Once nurses are equipped with mobile devices, paper becomes useless. Consequently, the process is simplified. Replacing the paper by a mobile device application is not straightforward. In order to access patient information, the tool must be linked to the existing CIS of the hospital without creating too strong dependencies. Moreover, the mobile interface must be adapted to the specificities of the mobile device such as a smaller display size, a reduced computational power, a tactile-based interaction and a real-time usage. Results: In order to link the mobile application to the existing CIS, we relied on a Service Oriented Architecture (SOA). It was mandatory to think of a software architecture that would not create a dependency with any legacy system. Thus, we defined a gateway server providing centralised access for the mobile application to any required information to or from the CIS. Integrating any mobile application would only require integrating this bridge. The gateway server also clearly separates the services that are available remotely from the ones proposed as usual Web services. The developed application not only allows the validation of the interventions and the input of measures, but it also offers a simple way to define the context in which nurses are working. This context is necessary to identify the specific list of interventions for the patients under the caregiver’s responsibility. The current CIS of the HUG includes a module that provides information concerning the interventions. Its interface is adjusted for a personal computer screen. Since caregivers are accustomed to this organisation of the information, we aimed to develop an interface on a mobile device that guarantees a certain level of homogeneity with the existing PC application. However, a mobile device’s screen is of limited size, therefore the interface has been completely rebuilt to be adapted to the new display. To deal with the limited display size, we rely on hierarchy and indexicality principles. For instance, based on the hypothesis that all tasks belonging to one category and planned at the same time can be regrouped under a single item; we regroup the interventions of similar top level in a common item. Moreover, to minimise user manipulations, relevant items are automatically moved to the top. Conclusion: The current daily workflow of nurses cannot be managed consistently using a unique tool. The need to switch from paper to computer induces work overload and is a source of errors. Therefore, we have developed a program running on a mobile device that nurses can carry during their visits. This program allows to manage nurses' daily interventions in real-time. The development of such a tool has required a complete reconstruction of the classical personal computer interface. This new interface takes into account a smaller display size, an innovative interaction paradigm, and real-time constraints.

Aviation systems represent a rich, difficult, and critical environment for usability. The life critical importance of aviation systems complemented by with their complexity and the diversity and uncertainty of environments in which they operate, place them necessarily on the avant-guard of usability. We describe the broad range of aviation missions, operators, and operating environments and relate these to key dimensions of usability and visual interfaces. We illustrate this concretely with two case examples: ground control stations for remotely piloted aircraft and air traffic management systems. We explore how in both these cases advances in machine autonomy and human control promise to enhance operator situational awareness and control, however, not without challenges. We share guidelines to ensure effective usability to include: require usability as a key performance parameter, architect and design systems and operations that incorporate affordances and fault tolerance, employ standards to increase learnability and interoperability, instrument environments to tailor usability, and assess effects (Maybury 2012). Finally, remaining challenges and future directions are discussed.

Comfort zone is an artificial mental boundary within which you maintain a sense of security. A couple of years ago, PRACE (Partnership for Advanced Computing in Europe) challenged the technology providers of Europe in proposing new architectures, new concepts and building a High-Performance Computer system mixing old and proven technology with advanced new components. E4 took the challenge and proposed an innovative and uncomfortable approach: DAVIDE. The talk will present the rationale for the technological and architectural choices done for building DAVIDE, the key innovative concepts, the software ecosystems and some preliminary performance.

Introduced in the early stages of software development, the Charmy framework assists the software architect in making and evaluating architectural choices. Rarely, the software architecture of a system can be established once and forever. Most likely poorly defined and understood architectural constraints and requirements force the software architect to accept ambiguities and move forward to the construction of a suboptimal software architecture. Charmy aims to provide an easy and practical tool for supporting the iterative modeling and evaluation of software architectures. From an UML-based architectural design, an executable prototype is automatically created. Charmy simulation and model checking features help in understanding the functioning of the system and discovering potential inconsistencies of the design. When a satisfactory and stable software architecture is reached, Java code conforming to structural software architecture constraints is automatically generated through suitable transformations. The overall approach is tool supported.

Software development has undergone various stages of paradigms - the very last one is called Object-Oriented (O-O) paradigm. Typical of this paradigm has been culminated by several OO programming languages such as C++, Java and VB. With the advent of Internetworking and evolvement of web technologies, business needs, especially isolated service requests/components, put a new demand on new software architecture. Existing models are examined in the light of their constraints and limitations to meet these constant changing business requirements. Service-oriented Architecture (SOA), as the next generation software architecture and through the utilization of the web service, XML and other related technologies provides viable working solution to implement dynamic e-business. This paper discusses SOA model and how it fits into implementing dynamic e-business solutions.

Millions of cellular phone power amplifiers (PAs) are produced every day worldwide using a great diversity of technologies. This is true both for the active devices, where various silicon as well as GaAs transistors are used, and for the PA architecture, in which MMIC, module, and discrete solutions compete. This paper gives an overview of the various technological and architectural choices and discusses their influence on the PA performance, notably the power efficiency and linearity. It sketches the future of PA development toward more functional integration, which may be obtained by two paths: integration on chip and added functionality in modules.

Millions of cellular phone power amplifiers (PA) are produced every day worldwide using a great diversity of technologies. This is true both for the active devices, where various silicon as well as GaAs transistors are being used, and for the PA design, in which MMIC, module and discrete solutions compete. This paper gives an overview of the various options for technological and architectural choices and their influence on PA performance, notably efficiency and linearity. It sketches the future of PA development towards more functional integration, which will be obtained by two paths: integration on chip and added functionality in modules.

Software architecture is a set of important decisions about the organization of the software system. The success and speed of the project development, the complexity of its support and understanding of the program structure depends on the correct choice of software architecture. For this reason, developers often use new architectural solutions to build software, trying to find the best solutions to a problem. The common practice of program development was the development on the principle of monolithic architecture, which envisages the project as a single program, which is responsible for all necessary functionality. Of course, this approach had its advantages, such as ease of development, testing and deploying. But with project`s growth, the monolithic architecture begins to make some flaws in the development process: the addition of a certain new functionality is accompanied by an increase in the code base, observance of limits of responsibility of internal modules is blurred, compiling and deploying takes much more time. Given the drawbacks of monolithic architecture above, developers have begun to take other approaches. One is microservice architecture. Microservice Architecture – A variant of service architecture (modular software development approach) software, focused on the interaction of as small as possible, loosely coupled and easily replaceable modules – microservices [1]. With such an architecture, the project is a set of small services, the communication between which is done through lightweight mechanisms (for example, HTTP, which can be used in REST architectural style to get an increased productivity and simplified architecture) [2]. Each of these services must fulfil its clearly defined business task. This architecture has the following advantages: better scaling, independent module development and deploying, better reusability etc.