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Environment Changes (environment + change)
Selected AbstractsArchitecture-based semantic evolution of embedded remotely controlled systemsJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 3 2003Lawrence Chung Abstract Evolution of a software system is a natural process. In most systems, evolution takes place during the maintenance phase of their life cycles. Those systems that have reached their limit in evolution have usually reached their end of useful life and may have to be replaced. However, there are systems in which evolution occurs during the operational phase of their life cycles. Such systems are designed to evolve while in use or, in other words, be adaptable. Semantically adaptable systems are of particular interest to industry as such systems often times adapt themselves to environment change with little or no intervention from their developing or maintaining organization. Since embedded systems usually have a restricted hardware configuration, it is difficult to apply the techniques developed for non-embedded systems directly to embedded systems. This paper focuses on evolution through adaptation and develops the concepts and techniques for semantic evolution in embedded systems. As the first step in the development of a software solution, architectures of software systems themselves have to be made semantically evolvable. In this paper we explore various architectural alternatives for the semantic evolution of embedded systems,these architectures are based on four different techniques that we have identified for semantic evolution in embedded systems. The development of these architectures follows the systematic process provided by the non-functional requirement (NFR) framework, which also permits the architectures to be rated in terms of their evolvability. As the field of embedded systems is vast, this paper concentrates on those embedded systems that can be remotely controlled. In this application domain the embedded system is connected to an external controller by a communication link such as ethernet, serial, radio frequency, etc., and receives commands from and sends responses to the external controller via the communication link. The architectures developed in this paper have been partly validated by applying them in a real embedded system,a test instrument used for testing cell phones. These architectures and techniques for semantic evolution in this application domain give a glimpse of what can be done in achieving semantic evolution in software-implemented systems. Copyright © 2003 John Wiley & Sons, Ltd. [source] A new genetic algorithm with diploid chromosomes using probability decoding for adaptation to various environmentsELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 8 2010Manabu Kominami Abstract This paper proposes a new diploid operation technique using probability for function optimization in nonstationary environments and describes a feature of diploid genetic algorithms (GAs). The advantage of the technique over previous diploid GAs is that one genotype is transformed into many phenotypes based on probability. This transformation is not made at random. It has a certain range of probabilities. Each individual has a range. The range allows adaptation to various environments. The technique allows genes to give a probabilistic representation of dominance, and can maintain the diversity of individuals. The experimental results show that the technique can adapt to severe environmental changes where previous diploid GAs cannot adapt. This paper shows that the technique can find optimum solutions with high probability and that the distribution of individuals changes when the environment changes. In addition, by comparing the proposed diploid GA with a haploid GA whose chromosome is twice the length, the features of the diploid are described. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(8): 38,46, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10097 [source] An Efficient Way to Assemble ZnS Nanobelts as Ultraviolet-Light Sensors with Enhanced Photocurrent and StabilityADVANCED FUNCTIONAL MATERIALS, Issue 3 2010Xiaosheng Fang Abstract Although there has been significant progress in the fabrication and performance optimization of one-dimensional nanostructure-based photodetectors, it is still a challenge to develop an effective and low-cost device with high performance characteristics, such as a high photocurrent/dark-current ratio, photocurrent stability, and fast time response. Herein an efficient and low-cost method to achieve high-performance ,visible-blind' microscale ZnS nanobelt-based ultraviolet (UV)-light sensors without using a lithography technique, by increasing the nanobelt surface areas exposed to light, is reported. The devices exhibit about 750 times enhancement of a photocurrent compared with individual nanobelt-based sensors and an ultrafast time response. The photocurrent stability and time response to UV-light do not change significantly when a channel distance is altered from 2 to 100,µm or the sensor environment changes from air to vacuum and different measurement temperatures (60 and 150,°C). The photoelectrical behaviors can be recovered well after returning the measurement conditions to air and room temperature again. The low cost and high performance of the resultant ZnS nanobelt photodetectors guarantee their highest potential for visible-blind UV-light sensors working in the UV-A band. [source] Emerging Patterns of Social Identification in Postapartheid South AfricaJOURNAL OF SOCIAL ISSUES, Issue 2 2010Elirea Bornman Theorists acknowledge the possibility of multiple group identification where groups are imbedded in hierarchical structures that can change as the environment changes. This article investigates national, subnational, and supranational identification and the possible impact of social and political change on identity structures in South Africa. The results of three surveys conducted in 1994, 1998, and 2001 are discussed. While national and African identities have apparently strengthened among Blacks since 1994, national identification seems to have diminished among Afrikaans-speaking Whites in favor of ethnic identification. Some potential consequences of and directions for future research are discussed. [source] Work-related carpal tunnel syndrome (WR-CTS) in Massachusetts, 1992,1997: Source of WR-CTS, outcomes, and employer intervention practices,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2004Helen Wellman MS Abstract Background The Massachusetts Sentinel Event Notification System for Occupational Risks (MASS SENSOR) receives reports of work-related carpal tunnel syndrome (WR-CTS) cases from (1) workers' compensation (WC) disability claims for 5 or more lost work days; and (2) physician reports (PR). Methods From 1992 through 1997, 1,330 WC cases and 571 PR cases completed follow-back surveys to provide information on industry, occupation, attributed source of WR-CTS, outcomes, and employer intervention practices. Results Sixty-four percent of the respondents had bilateral CTS and 61% had surgery, both of which were proportionally more frequent among WC cases. Office and business machinery was the leading source of WR-CTS (42% of classifiable sources) in every economic sector except construction, followed by hand tools (20%). Managers and professional specialty workers were the most likely to report employers' interventions and were up to four times more likely to report equipment or work environment changes than higher risk groups. Conclusions State-based surveillance data on the source of WR-CTS provided valuable information on how and where to implement interventions. New occurrences of WR-CTS are likely, especially in the highest risk industries where very few cases reported primary prevention measures (e.g., changes to equipment or work environment) implemented by their employers. Am. J. Ind. Med. 45:139,152, 2004. © 2004 Wiley-Liss, Inc. [source] Coroners' recommendations following fatal heavy vehicle crash investigationsAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 2 2010Lisa Brodie Abstract Objective: This paper quantifies and describes the nature of coroners' recommendations and comments on fatal heavy vehicle crashes in Victoria, Australia. Methods: A retrospective, descriptive study was performed using coroners' findings. Fatal heavy vehicle crashes between January 2001 and December 2007 were identified through coronial databases. Individual findings were examined by incident type. Identified recommendations or preventative comments were reviewed and compared with national heavy vehicle safety objectives. Results: Of 330 fatal crashes, which resulted in 376 deaths, recommendations were made in 21 incidents (6%). From these 21 incidents, 45 separate recommendations or comments were made by coroners. Ten (22%) called for specific remedial action, predominantly targeting road environment changes; the remainder had a broader application for prevention. Of the 21 incidents from which these recommendations arose, 11 (52%) were from a public inquest. No recommendation was made following any of the 45 single heavy vehicle crashes. Conclusion: The frequency of coroners' recommendations varied by crash nature including vehicle type involved and number of resulting fatalities. Multiple factors are likely to influence their development, including the holding of a public inquest and the perceived level of preventability. Implications: Coroners' investigations serve an important public health and safety role. Recognition of the significance of recommendations for reducing the extent of injury from heavy vehicle crashes and monitoring of their uptake is vital. [source] | ||||||||||