This work presents the first steps towards the development of a toolkit for aiding in the construction of Distributed Cognitive Systems, designed within the spirit of the System of Systems (SoS) paradigm. The Toolkit ...
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ISBN:
(数字)9781728176475
ISBN:
(纸本)9781728176482
This work presents the first steps towards the development of a toolkit for aiding in the construction of Distributed Cognitive Systems, designed within the spirit of the System of Systems (SoS) paradigm. The Toolkit is language agnostic and general enough to be used in building problem-specific Cognitive Systems that can spread across several physical or virtual devices such as low-power computers, microcontrollers, and virtual containers. The Toolkit is conceived targeting to be suitable for IoT and Smart City applications.
Among the great variety of programminglanguages, java stands out vividly, becoming, for several decades, one of the most preferred languages for programmers. Introduced only a few years ago, Kotlin is one of the many...
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Writing code to interact with external devices is inherently difficult, and the added demands of writing device drivers in C for kernel mode compounds the problem. This environment is complex and brittle, leading to i...
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ISBN:
(纸本)9781931971683
Writing code to interact with external devices is inherently difficult, and the added demands of writing device drivers in C for kernel mode compounds the problem. This environment is complex and brittle, leading to increased development costs and, in many cases, unreliable code. Previous solutions to this problem ignore the cost of migrating drivers to a better programming environment and require writing new drivers from scratch or even adopting a new operating system. We present Decaf Drivers, a system for incrementally converting existing Linux kernel drivers to java programs in user mode. With support from program-analysis tools, Decaf separates out performance-sensitive code and generates a customized kernel interface that allows the remaining code to be moved to java. With this interface, a programmer can incrementally convert driver code in C to a java decaf driver. The Decaf Drivers system achieves performance close to native kernel drivers and requires almost no changes to the Linux kernel. Thus, Decaf Drivers enables driver programming to advance into the era of modern programminglanguages without requiring a complete rewrite of operating systems or drivers. With five drivers converted to java, we show that Decaf Drivers can (1) move the majority of a driver's code out of the kernel, (2) reduce the amount of driver code, (3) detect broken error handling at compile time with exceptions, (4) gracefully evolve as driver and kernel code and data structures change, and (5) perform within one percent of native kernel-only drivers.
The usage of licensed television spectrum by unlicensed user to improve spectrum utilisation has been described by the IEEE 802.22 standard which seeks to use cognitive radios for wireless regional area networks. This...
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ISBN:
(数字)9781728131269
ISBN:
(纸本)9781728131276
The usage of licensed television spectrum by unlicensed user to improve spectrum utilisation has been described by the IEEE 802.22 standard which seeks to use cognitive radios for wireless regional area networks. This standard is meant for usage in the rural areas where there is low usage of the TV spectrum. To make this standard available for use in the urban areas where there is greater usage of the TV spectrum; a new spectrum utilisation technique for cognitive radios is developed. This method uses the principle of matched filtering for spectrum sensing and interference temperature management for interference control against the licensed user. In the system modelling, cognitive radio access point transmits with the maximum transmission power of 36dBm when there is absence of television signal but has to compute the appropriate transmission power which is determined by the strength of the television signal present. Simulation of the developed method was done using java programming language. In the presence of different licensed signal levels of -34.80dBm, -14.80dBm and -7.81dBm, the developed method achieved a distance of 150m, 1.5km and 3.5km respectively at 66MHz, a capacity of 789Kb/s, and a spectral efficiency of 0.045b/s/Hz.. This developed method therefore gives improved spectrum utilisation in areas where there is higher usage of the limited spectrum.
Deadlock immunity is a property by which programs, once afflicted by a given deadlock, develop resistance against future occurrences of that and similar deadlocks. We describe a technique that enables programs to auto...
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ISBN:
(纸本)9781931971652
Deadlock immunity is a property by which programs, once afflicted by a given deadlock, develop resistance against future occurrences of that and similar deadlocks. We describe a technique that enables programs to automatically gain such immunity without assistance from programmers or users. We implemented the technique for both java and POSIX threads and evaluated it with several real systems, including MySQL, JBoss, SQLite, Apache ActiveMQ, Limewire, and java JDK. The results demonstrate effectiveness against real deadlock bugs, while incurring modest performance overhead and scaling to 1024 threads. We therefore conclude that deadlock immunity offers programmers and users an attractive tool for coping with elusive deadlocks.
Context: Algorithms for generating a safe fluent API have been actively studied in recent years. A safe fluent API is a fluent API that reports incorrect chaining of the API methods as a type error to the API users. A...
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Context: Algorithms for generating a safe fluent API have been actively studied in recent years. A safe fluent API is a fluent API that reports incorrect chaining of the API methods as a type error to the API users. Although such a safety property improves the productivity of users, the construction of a safe fluent API is excessively complicated for developers. Therefore, generation algorithms are studied to reduce the development costs of a safe fluent API. Such studies may beneft many programmers, as a fluent API is a popular design in the real world. Inquiry: The generation of a generic fluent API remains unaddressed. A generic fluent API refers to a fluent API that provides generic methods (those that contain type parameters in their defnitions). The Stream API in java is an example of a generic fluent API. Previous studies on safe fluent API generation have focused on the grammar classes that the algorithms can deal with for syntax checking. The key concept of such studies is using nested generics to represent a stack structure for the parser built on top of the type system. Within this context, the role of a type parameter has been limited to the internal representation of a stack element of that parser on the type system. Library developers cannot use type parameters to include a generic method in their API so that the semantic constraints for their API will be statically checked;for example, the type constraint on the items passed through a stream. Approach: We propose an algorithm for generating a generic fluent API. Our translation algorithm is modeled as the construction of deterministic fnite automaton (DFA) with type parameter information. Each state of the DFA holds information regarding which type parameters are already bound in that state. This information is used to identify whether a method invocation in a chain newly binds a type to a type parameter or refers to a previously bound type. This identifcation is necessary because a type parameter in
This study was aimed to determine the level of knowledge of beef cattle farmers towards artificial insemination (AI) and to identify the success of the AI implementation by observing at the cow's pregnancy rate. T...
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The demand for computer engineers has grown considerably and in the Computer Engineering Career of the School of Exact Sciences, of the Universidad Estatal a Distancia (UNED), which it’s population has grown a little...
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Cloud platforms offer diverse evolving programming and deployment models which require not only application code adaptation, but also retraining and changing developer mindsets. Such change is costly and is better ser...
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