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1.
The last few years have seen the development of Discrete Event-Dynamic Net Systems1,2 as instruments for modeling complex systems. They are able to achieve the following objectives:

—formality of the modeling methodology

—ability to model static and dynamic aspects

—ability to pass between levels of differently rich structures by morphisms

—uniform representation of the communication process as

—an information process

—a decision process and

—a control process

—homogeneity of the representation and modeling methods

—ability to derive qualitative and quantitative statements.

The foundation is provided by a Discrete Event-Dynamic Net System which includes the axiomatic declaration of general Petri nets. In order to calculate the structural and dynamic aspects, so-called Petri net machines are developed. It is shown that this approach can even be used to treat the following aspects:

—use of time during the process

—increase of costs during the generation and transportation of information

—augmentation, evaluation and transformation of information objects.

Recursive formulas are derived and some examples calculated.  相似文献   


2.
Background: Smartphones have reached levels of popularity and penetration where they are now suitable for use in population health interventions. A key feature of smartphones is push notification or in app messaging service, which can be used to alert users to messages or instructions pertaining to an installed app. Little evidence exists as to the persuasive power of these messages.

Method: We conducted a 24-week live user evaluation of push notifications used in a behavior-based mobile app for a meal replacement program to understand the role of push notifications in persuading users to engage with self-monitoring tasks.

Results: User perception of the prompts were verified through questionnaires, which in conjunction with the interaction logs show that users were tolerant of multiple daily prompts. The decline in compliance to the tasks set, however, shows that while the participants did not object to receiving prompts, they were less likely to respond to them as the study progressed.

Conclusions: Push notifications and user tasks are appropriate mechanisms to engage users with mobile technology in the short term.  相似文献   


3.
The Problem

Internet of Things (IoT) is providing new services and insights by sensing contextual data but there are growing concerns of privacy risks from users that need immediate attention.

The Reason

The IoT devices and smart services can capture Personally Identifiable Information (PII) without user knowledge or consent. The IoT technology has not reached the desired level of maturity to standardize security and privacy requirements.

The Solution

IoT Privacy by Design is a user-centric approach for enabling privacy with security and safety as a ‘win-win’ positive outcome of IoT offerings, irrespective of business domain. The Proactive and Preventive Privacy (3P) Framework proposed in this paper should be adopted by the IoT stakeholders for building trust and confidence in end users about IoT devices and smart services.  相似文献   


4.
Many attempts1, 7, 8, 35 have been made to overcome the limit imposed by the Turing Machine34 to realise general mathematical functions and models of (physical) phenomena.

They center around the notion of computability.

In this paper we propose a new definition of computability which lays the foundations for a theory of cybernetic and intelligent machines in which the classical limits imposed by discrete algorithmic procedures are offset by the use of continuous operators on unlimited data. This data is supplied to the machine in a totally parallel mode, as a field or wave.

This theory of machines draws its concepts from category theory, Lie algebras, and general systems theory. It permits the incorporation of intelligent control into the design of the machine as a virtual element. The incorporated control can be realized in many (machine) configurations of which we give three:

a) a quantum mechanical realization appropriate to a possible understanding of the quantum computer and other models of the physical microworld,

b) a stochastic realization based on Kolmogorov-Gabor theory leading to a possible understanding of generalised models of the physical or thermodynamic macroworld, and lastly

c) a classical mechanical realization appropriate lo the study of a new class of robots.

Particular applications at a fundamental level are cited in geometry, mathematics, biology, acoustics, aeronautics, quantum mechanics, general relativity and. Markov chains. The proposed theory therefore opens a new way towards understanding the processes that underlie intelligence.  相似文献   


5.
This paper is a study of an adaptive quality control system from a viewpoint of quality goal. The main purpose is to introduce a conceptual framework for setting up quality goals which are in accordance with the external environment and internal capacity of quality control systems. We apply a mathematical general systems approach.

The results of our paper are summarized as follows:

1)As important decision-making in adaptive QCS, the decision-making for estimalion of fitness and examination of attainability are proposed and formalized mathematically.

2)A refinement process is formalized in which models are revised according to the changes of market.

3)Basic steps for setting quality goals are obtained which are based on the above formalization.  相似文献   


6.
This article explains, demonstrates, and evaluates Chaum’s protocol for detecting a man-in-the-middle (MitM) of text-messaging network communications. MitM attacks pose serious risks to many network communications. Networks often mitigate these risks with robust protocols, such as TLS, which assume some type of public-key infrastructure that provides a mechanism for the authenticated exchange of public keys. By contrast, Chaum’s protocol aims to detect a MitM with minimal assumptions and technology, and in particular without assuming the authenticated exchange of public keys. Chaum assumes that the eavesdropper can “sound like” the communicants but that the eavesdropper cannot fabricate sensible conversations.

Using an encryption function and one-way function, Chaum’s protocol works in three phases. In Phase I, the communicants exchange their public keys. In Phase II, each communicant generates a random string. The first communicant cryptographically commits to that string, and sends the string to the other communicant after receiving the other’s string. In Phase III, using any of four different “scenarios” the communicants verify that each possesses the same two strings. The protocol forces any MitM to cause the communicants to possess different pairs of strings. The text-messaging scenario is similar to a forced-latency protocol proposed by Wilcox-O’Hearn in 2003.

This article implements and experimentally demonstrates the effectiveness of the third scenario, which uses timing to detect a MitM in text-messaging. Even assuming a MitM can send messages without any network latency, the protocol forces the MitM to cause delays noticeable by the communicants. This article is the first to explain, demonstrate, and evaluate Chaum’s protocol, which Chaum described only in an abandoned and nearly inscrutable patent application.  相似文献   


7.
Book reviews     
Computer Software: legal protection in the United Kingdom Henry Carr & Richard Arnold, 1992 London: Sweet & Maxwell, 2nd ed, xv + 312 pp., £45.00 (hardback)

Advanced Information Systems for Lawyers V. Mital & L. Johnson, 1992 London: Chapman & Hall. pp. 306, £35.00

Law of Contract Laurence Koffman & Elizabeth MacDonald, 1992 London: Fourmat Publishing, 430 pp., paperback £22.50

The Electronic Media and the Transformation of Law M. Ethan Katsh, 1991 Oxford: Oxford University Press. £13.95  相似文献   


8.
Book reviews     
Crime and the Computer, Martin Wasik, 1991, Oxford: Clarendon Press. £35.00.

Yearbook of Law, Computers and Technology, Volume 5. K.V. Russell (Ed.), 1991. London: Butterworths. £29.50.

Computers, Artificial Intelligence and the Law. Mervyn E. Bennun (Ed.), 1991. London: Ellis Horwood. xx +132 (including bibliography & index), £26.50

Modelling Legal Argument: reasoning with cases and hypotheticals. Kevin D. Ashley, 1990. Cambridge: MIT Press. 329 pp.  相似文献   


9.
Purpose: Identify location and intensity of discomfort experienced by healthy participants wearing cervical orthoses.

Method: Convenience sample of 34 healthy participants wore Stro II, Philadelphia, Headmaster, and AspenVista® cervical orthoses for four-hour periods. Participants reported discomfort level (scale 0–6) and location.

Results: Participants reported mean discomfort for all orthoses over the four-hour test between ‘a little discomfort’ and ‘very uncomfortable’ (mean discomfort score = 1.64, SD = 1.50). Seven participants prematurely stopped tests due to pain and six reported maximum discomfort scores. Significant linear increase in discomfort with duration of wear was found for all orthoses. Significantly less discomfort was reported with Stro II than Headmaster and Philadelphia. Age correlated with greater perceived discomfort. Orthoses differed in the location discomfort was experienced.

Conclusion: Existing cervical orthoses cause discomfort influenced by design and duration of wear with orthoses’ design the more significant factor. This work informed the design of a new orthosis and future orthoses developments.

Practitioner Summary: The purpose of this study was to gain greater knowledge about the discomfort caused by wearing of existing neck orthoses in order to inform the design and development of a new neck orthosis. This study gathers empirical data from a surrogate population and concludes that orthosis design is more influential than the duration of wear.  相似文献   


10.
Conventional information science generally considers an information process, but traditionally uses the probability measure for random events, and Shannon’s entropy measure as an uncertainty function of the states. The cutting process on separated states decreases quantity information concealed in the states correlation, holding hidden process information.

Up to now, “information process” has not had a scientifically conclusive definition nor its implicit structure.

The presenting information process performs logical operations with discrete information units (Bits) to achieve a goal, integrating the discrete mutually connected sequence of symbols and the extracting process’ hidden information in the structure of an information Observer. The probing time-space observation develops the unit of space-time geometry-memorizing logic.

The defined information process starts generating observations of a random process via the logic of probing impulses, sequentially cutting the process entropy measure and creating the discrete information units whose integration enfolds the information geometrical structure of an Observer. Found composite stages of the information process and the synthesized optimal process trajectory minimize observation time in an artificially designed information Observer with intellectual searching logic. The analytical modeling, computer simulations, and experimental applications validate the results.  相似文献   


11.
The construction of automatic control and modelling environments has been attempted using shallow reasoning expert systems. The inadequacy of this approach for real-life systems has become apparent, and the need for deeper knowledge—which can only be obtained by extensive simulation—is now acknowledged.

The simulation process, which consists of model building and model selection, followed by the generation and execution of a software simulator, can be partially automated if an Object-Oriented methodology is adopted. In this article, a methodology is presented, which is presently under investigation in the DESiRE (Dynamic Expert Systems in Robotic Experimentation)project

In the modelling phase, a hierarchical, uniform way of describing and manipulating continuous and discrete models is needed, if the highly desirable reusability of submodels is to be achieved. This is only possible if a clear distinction is made between bare models (and information about their intrinsic coupling) and causal simulation experiment-related data.

In the simulation phase, before generating numerical simulation code, a symbolic reduction of the continuous parts of the model is performed, thus eliminating inaccuracy introduced by the untimely application of possibly unstable numerical algorithms.

Finally, from the reduced representation, executable simulator-objects are produced for use in a distributed environment.  相似文献   


12.
During the last few months of 1932, the Polish mathematician Marian Rejewski solved the problem of finding the internal connections of the rotors and reflector of the Enigma cipher machine used by the German army at that time. This allowed the Polish Cipher Bureau to construct an analogue of the machine, and subsequently to find effective methods for deciphering secret messages. Rejewski performed this feat virtually alone using cryptographic material provided by the Polish secret services. His knowledge of the theory of permutation groups was essential in solving this problem.

This article describes in detail how to find the complete wiring of the rotors and reflector of Enigma, as well as other specifics, using data that Rejewski had at his disposal, by systematically presenting the resolution of all cases that could have been encountered. Similarly, we complete those stages of the procedure that were only outlined by Rejewski.  相似文献   


13.
Book reviews     
Electronic Finance Law Chris Reed, 1993 Hemel Hempstead: Woodhead‐Faulkner. 450 pp. £50.00

Introduction to Computer Law, 2nd Edn David I. Bainbridge, 1993 London: Pitman £18.99

Deontic Logic in Computer Science: normative system specification John‐Jules CH. Meyer & Roel J. Wieringa, 1993 London: John Wiley £34.95, xiv + 317pp.  相似文献   


14.
In the practice of Japanese company-wide quality control, some tools which help us to coordinate company-wide activities are developed. One of the main functions of these tools is to organise the diversified information related to the company-wide activities

This report discusses the basic recognition underlying the use of these tools, and presents on a conceptual level an essential philosophy and methodology of coordinating company-wide activities

The basic idea of this report is to make an additional subsystem which helps us to organize the diversified information of activities in order to coordinate activities easily.  相似文献   


15.
This article sets out to identify the typical risky situations experienced by novice motorcyclists in the real world just after licensing. The procedure consists of a follow-up of six novices during their first two months of riding with their own motorbike instrumented with cameras. The novices completed logbooks on a daily basis in order to identify the risky situations they encountered, and were given face-to-face interviews to identify the context and their shortcomings during the reported events. Data show a large number of road configurations considered as risky by the riders (248 occurrences), especially during the first two weeks. The results revealed that a lack of hazard perception skills contributed to the majority of these incidents. These situations were grouped together to form clusters of typical incident scenarios on the basis of their similarities. The most frequent scenario corresponds to a lane change in dense traffic (15% of all incidents). The discussion shows how this has enhanced our understanding of novice riders’ behaviour and how the findings can improve training and licensing. Lastly, the main methodological limitations of the study and some guidelines for improving future naturalistic riding studies are presented.

Practitioner Summary:

This article aims to identify the risky situations of novice motorcyclists in real roads. Two hundred forty-eight events were recorded and 13 incident scenarios identified. Results revealed that a lack of hazard perception contributed to the majority of these events. The most frequent scenario corresponds to a lane change in dense traffic.  相似文献   


16.
Like most criminal subsets of society, cyber criminals are going to very when it comes to motivation and capability. Cybercrime talent ranges from entrepreneurial “lone wolf” brute force attackers such as: Nathan Wyatt (who may or may not be) affiliated with “The Dark Overloads” to Evgeniy Mikhailovich Bogachev, the creator of the stealthy and sophisticated ZeuS Banking Trojan.

Law enforcement’s work on disassembling the Citadel Banking Trojan in 2013, a variant of the ZeuS Baking Trojan brought light multiple tiers of cybercriminals. Dimitry Belorossov a/k/a Rainerfox, was alleged to have operated a Citadel command and control server ultimately controlling 7,000 victim computers. This cybercriminal essentially purchased Citadel – really nothing more than a “user”. Stepping up one level of cyber-crime capability we have the extradition and arrest of Mark Vartanyan, a/k/a Kolypto, wo allegedly developed, improved and maintained the Citadel banking Trojan – a malware developer. Finally, at the top end of the cybercriminal scale we have “Aquabox” the alleged creator of the Citadel Banking. In 2013, it was announced the Citadel Banking Trojan responsible for stealing $500 million. Aquabox is still at large.

This journal paper explores cybercriminal actors from a unique perspective: by the type of the attack they conduct and the relationship of the malicious actor to the victim business. Understanding the relationship of the actor to the type of attack inflicted provides an understanding of the motivation of the individual or group. Understanding the motivation of these criminals can provide valuable insight into countering both insider and external threats.  相似文献   


17.
Book reviews     
Patent Harmonization Harold C. Wegner London, Sweet & Maxwell, 1993 xx + 376 pp., £70.00 (hardback)

Of Authors and Origins: essays on copyright law Brad Sherman & Alain Strowel (Eds) Oxford, Clarendon Press, 1994 xiv + 313 pp., £30.00 (hardback)

Future Air Navigation Systems Werner Guldimann & Stefan Kaiser Dordrecht, Martinus Nijhoff, 1993 Utrecht Studies in Air and Space Law, Vol. 13 viii + 281 pp., £76.50 (hardback)

The Law of Copyright Terence Prime London, Fourmat Publishing, 1992, xxiv + 313 pp., £30.00 (paperback)  相似文献   


18.
The three-compartment model (3CM) was validated previously for prediction of endurance times by modifying its fatigue and recovery rates. However, endurance times do not typically represent work demands, and it is unknown if the current version of the 3CM is applicable for ergonomics analysis of all occupational tasks. The purpose of this study was to add biological fidelity to the 3CM, and validate the model against a series of submaximal force plateaus. The fatigue and recovery rates were modified to represent graded physiological motor unit characteristics (termed 3CMGMU). In nine experiments of submaximal efforts, the 3CMGMU produced a root-mean squared difference (RMSD) of 4.1 ± 0.5% MVC over experiments with an average strength loss (i.e. fatigue) of 31.0 ± 1.1% MVC. The 3CMGMU model performed poorly for endurance tasks. The 3CMGMU model is an improvement for evaluating submaximal force patterns consisting of intermittent muscle contractions of the hand and forearm.

Practitioner Summary: We modified an existing fatigue model using known physiological properties in order to predict fatigue during nine different submaximal force profiles; consistent with efforts seen in industrial work. We expect this model to be included in digital human modelling software, for the assessment of repetitive work and muscle fatigue in repetitive tasks.

Social Media Summary: The proposed model has applications for estimating task fatigue in proactive ergonomic analyses of complex force patterns using digital human models.  相似文献   


19.
A general methodology for empirical investigaiion is described which consists of: (i) the selection of a system on the object of investigation with respect to the purpose and constraints of investigation, (ii) the gathering of data for the system and organizing them in the form of activity arrays, (iii) the processing of the data through which certain time-invariant properties representing the data are determined, (iv) the interpretation of these time-invariant data representations from the standpoint of the purpose of investigation.

It is shown that each activity array yields many different representations. A procedure through which the various representations can be obtained is described that consists of: (1) the selection of a mask specifying a pattern for sampling the data, (2) the sampling procedure through which certain types of time-invariant relations are determined for the given mask, (3) the simplification of the time-invariant relations, if necessary or desirable.

A basis for the objective comparison of possible representations and ascertainment of the representation with the highest possible degree of determinism, subject to given constraints, is developed.

The procedure is applicable to both well defined and fuzzy variables of any scale. No classification into input and output variables is required, although it is not prohibited.  相似文献   


20.
Lal Balkaran 《EDPACS》2016,54(3):1-10
A company’s strategic plan is its long-term outlook that sets out the plans, goals, objectives and actions for the next three to ten years. The board needs an objective assurance that the plan was properly developed. The internal audit function is best positioned to provide this assurance. The reason: it is one of the board’s most powerful mechanisms for understanding the full spectrum of key governance, risk, and control issues facing the company embodied in the strategic plan.

Auditing a strategic plan begins with a review of what it constitutes (its elements) and the methodology (its process) used in developing the plan. It thus becomes much easier to focus the audit effort in determining whether the output for each step along the way in these two broad streams has been achieved.

If not carefully planned and executed, a strategic plan audit could do irreparable damage to the reputation of the audit effort throughout the organization. As a result, it requires a multi-talented team with a high-powered leader, preferably the chief audit executive.

Although a strategic plan fails due to such common factors as planning teams lacking an understanding of the business, lack of commitment, not having the right people, or not adapting to a changing environment to take full advantage of technological developments, there is a key reason often overlooked: lack of an audit of the plan itself which, if done properly, could uncover these reasons for failure long before they happen.  相似文献   


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