45073197
On cognitive properties of human factors in engineering
Human traits and needs are the fundamental force underlying almost all phenomena in human task performances, engineering organizations, and societies. This paper explores the cognitive foundations of human traits and cognitive properties of human factors in engineering. The fundamental traits of human beings are identified, and the hierarchical model of basic human needs is formally describes. The characteristics of human factors and their influences in engineering organizations and socialization are explored. Based on the models of basic human traits, needs, and their influences, driving forces behind the human factors in engineering and society are revealed. A formal model of human errors in task performing is derived, and case studies of the error model in software engineering are presented.
16244688
Formal Description of Time Management in Real-Time Operating Systems
This paper describes the formal specification of the time management subsystem of a real-time operating system. Real-time process algebra (RTPA) is adopted to formally specify the system. The architecture, static behaviors, and dynamic behaviors of a CPU time manager are systematically specified that form an abstract model of the system. The formal specifications are implemented in C, on which the system performance can be tested and verified
21184887
The cognitive processes of abstraction and formal inferences
Theoretical research is predominately an inductive process; while applied research is mainly a deductive process. Both inference processes are based on the cognitive process and means of abstraction. This paper describes the cognitive processes of abstraction and formal inferences such as deduction, induction, abduction, and analogy. The hierarchy of abstraction and the descriptivity of abstract means at different levels are analyzed. A set of mathematical models of formal inference methodologies are developed. Formal descriptions of the five cognitive processes of abstraction and inferences are presented using real-time process algebra (RTPA). Applications of abstraction and formal inferences in dealing with complicated problems in large-scale software system development in software engineering are discussed.
29450095
Cognitive models of the brain
The human brain is the most complicated organ in the universe and a new frontier yet to be explored in an interdisciplinary approach. Investigation of the brain is a unique problem that requires recursive mental power to explore the brain using the brain. This paper attempts to develop functional and cognitive models of the brain by using cognitive informatics and formal methodologies. This paper adopts a memory-based approach to explore the brain, and to demonstrate that memory is the foundation for any natural intelligence. Structures of memories are explored and cognitive models of the natural intelligence are proposed. Cognitive mechanisms of the brain, including hypotheses and theories on the thinking engine of the brain, long-term memory establishment, and roles of sleep in long-term memory development, are investigated. The models and theories are applied to explain a number of fundamental physiological and psychological phenomena.
40360434
Measurement of the cognitive functional complexity of software
One of the central problems in software engineering is its inherited complexity. It is recognized that cognitive informatics plays an important role in understanding the fundamental characteristics of software. This paper models the cognitive weights of basic control structures of software, and develops a new concept of cognitive functional size for measuring software complexity. Comparative case studies between the cognitive functional size and physical sizes of 20 programs are conducted. It is found that for a given design, although the physical sizes of software may vary in a wide range, the cognitive functional sizes are much stable and independent from implementation technologies and programming languages. Therefore, the cognitive functional size provides a novel, stable and practical software complexity measurement and is helpful to explain the fundamental nature of software complexity in the phase of design, implementation, or maintenance in software engineering.
21455681
A layered reference model of the brain
Based on the advances of research in cognitive informatics and related fields, this paper attempts to develop a layered reference model of the brain that explains the functional mechanisms and cognitive processes of the natural intelligence. A variety of life functions and cognitive processes have been identified in cognitive informatics, cognitive science, neuropsychology, and neurophilosophy. In order to formally and rigorously describe a comprehensive and coherent set of mental processes and their relationships, an integrated reference model of the brain is established, which encompasses 37 cognitive processes at six layers known as the sensation, memory, perception, action, meta and higher cognitive layers from bottom up. The reference model of the brain may be applied to explain a wide range of physiological, psychological, and cognitive phenomena in cognitive informatics, particularly relationships between the inherited and the acquired life functions, as well as the subconscious and conscious cognitive processes.
11122272
Modeling with Structures in Statistical Machine Translation
Most statistical machine translation systems employ a word-based alignment model. In this paper we demonstrate that word-based alignment is a major cause of translation errors. We propose a new alignment model based on shallow phrase structures, and the structures can be automatically acquired from parallel corpus. This new model achieved over 10% error reduction for our spoken language translation task.
15897925
Error exponents for channel coding with side information
Capacity formulas and random-coding and sphere-packing exponents are derived for a generalized family of Gel'fand-Pinsker coding problems. Information is to be reliably transmitted through a noisy channel with random state sequence. Partial information about the state sequence is available to the encoder and decoder. Two families of channels are considered: (1) compound discrete memoryless channels (C-DMC); and (2) channels with arbitrary memory, subject to an additive cost constraint, or more generally to a constraint on the conditional type of the channel output given the input. Both problems are closely connected. For the C-DMC case, our random-coding and sphere-packing exponents coincide at high rates, thereby determining the reliability function of the channel family. The random-coding exponent is achieved using a 3D binning scheme and a maximum penalized mutual information decoder. In the case of arbitrary channels, with memory, a larger random-coding error exponent than in the C-DMC case is obtained. Applications of this study include watermarking, data hiding, communication in presence of partially known interferers, and problems such as broadcast channels, all of which involve the fundamental idea of binning.
13960849
NTS6: IPv6 based Network Topology Service System of CERNET2
In this paper, we propose NTS6, an IPv6 based network topology service system, which provides a query and response service of network topology information between any pair of hosts accessing IPv6 Internet via CERNET2. The NTS6 system periodically collects the latest OSPF, BGP and SNMP information of CERNET2. Based on these information, NTS6 provides network topology information such as net distance, available bandwidth and path packet loss in response to users' query. The real-world experiment on CERNET2 confirms the accuracy of our system. Also, NTS6 now performs well on large deployed maze P2P file-sharing system. We believe NTS6 will be a powerful middleware for other applications.
8456748
Friends Troubleshooting Network: Towards Privacy-Preserving, Automatic Troubleshooting
Content sharing is a popular usage of peer-to-peer systems for its inherent scalability and low cost of maintenance. In this paper, we leverage this nature of peer-to-peer systems to tackle a new problem: automatic misconfiguration troubleshooting. In this setting, machine configurations from the peers are “shared” to diagnose the misconfigurations on a sick machine. A key challenge for such a troubleshooting system is privacy preservation. To this end, we construct Friends Troubleshooting Network (FTN), a peer-to-peer overlay network, where the links between peer machines reflect the friendship of their owners. To preserve privacy, we use historyless and futureless random-walk in the FTN, during which search along with parameter aggregation are carried out for the purpose of troubleshooting. Many of our techniques can be applied to other application scenarios that require privacy-preserving distributed computing and information aggregation. We have also identified a number of open challenges that remain to be addressed.
3088453
Reverse engineering goal models from legacy code
A reverse engineering process aims at reconstructing high-level abstractions from source code. This paper presents a novel reverse engineering methodology for recovering stakeholder goal models from both structured and unstructured legacy code. The methodology consists of the following major steps: 1) Refactoring source code by extracting methods based on comments; 2) Converting the refactored code into an abstract structured program through statechart refactoring and hammock graph construction; 3) Extracting a goal model from the structured program's abstract syntax tree; 4) Identifying nonfunctional requirements and derive soft goals based on the traceability between the code and the goal model. To illustrate this requirements recovery process, we refactor stakeholder goal models from two legacy software code bases: an unstructured Web-based email in PHP (SquirrelMail) and a structured email client system in Java (Columba).