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1.
Mining work boots provide an interface between the foot and the ground, protecting and supporting miners’ feet during lengthy coal mining shifts. Although underground coal miners report the fit of their work boots as reasonable to good, they frequently rate their boots as uncomfortable, suggesting that there is a mismatch between the shape of their feet and their boots. This study aimed to identify whether dimensions derived from the three-dimensional scans of 208 underground coal miners’ feet (age 38.3 ± 9.8 years) differed from the internal dimensions of their work boots. The results revealed underground coal miners wore boots that were substantially longer than their feet, possibly because boots available in their correct length were too narrow. It is recommended boot manufacturers reassess the algorithms used to create boot lasts, focusing on adjusting boot circumference at the instep and heel relative to increases in foot length.

Practitioner Summary: Fit and comfort ratings suggest a mismatch between the shape of underground coal miners’ feet and their boots exists. This study examined whether three-dimensional scans of 208 miners’ feet differed from their boot internal dimensions. Miners wore boots substantially longer than their feet, possibly due to inadequate width.  相似文献   


2.
The concept of a sensor with finite resolution is chosen as the cornerstone of a physical measurement theory. It is concluded that the concept of a band-limited channel is less appropriate for this purpose because it is defined with help of specific mathematical operators on functions that are defined on an infinite interval.

It is shown that measurement in continuum physics requires transfer, transformation and transport of energy to, by, and through a sensor: a non-equilibrium process. As theory requires equilibrium for any measurement, a paradox arises. It is indicated that experimental physics avoids this paradox with help of a hierarchy of space and time scales. The definitions and propositions are formulated in a similar way in order to avoid this equilibrium/non-equilibrium paradox.

The equivalence of the various forms of energy, as stated by the first law of thermodynamics and verified by experimental physics, renders interpretation of physical measurement relatively easy.

Signals are defined to be products of measurement. They are carriers of a finite amount of information. As the class of continuous functions generate an infinite amount of information, discrete functions are selected to represent sampled and digitized signals. If the sampling interval is of the order of the largest characteristic time scale of the total system, then little information is lost by digitization. The number of significant digits is related to the resolution of the sensor and of the other parts of the measuring instrument. A measuring instrument is shown to be composed of a chain or a set of chains of sensors.  相似文献   


3.
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   


4.
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   


5.
Background: Tablet computers are increasingly widespread in this digital era. During tablet computer use, two important factors are display quality and ambient illumination. The purpose of this experiment was to understand the effects of the display quality of tablet computers (a Sony, a Samsung, and an iPad) and ambient illumination levels (200 lx, 500 lx) on visual fatigue, comfort perception, and task performance.

Methods: Thirty-five university students (17 males and 18 females) were recruited for this experiment. They performed six 40-min trials of playing computer games in all experimental conditions. Visual fatigue, comfort perception, and task performance were collected at the end of each trial.

Results and Discussion: There were no interactions between display model and ambient illumination. Display model had a significant effect on visual fatigue and visual performance, and the best display quality caused less visual fatigue during long periods of viewing. We found no significant effect between 200 lx and 500 lx of ambient illumination on visual fatigue or visual performance; therefore, further research should be conducted to determine what levels of ambient illumination, both high and low, can affect visual fatigue and task performance.  相似文献   


6.
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   


7.
The purpose of this study was to develop anti-heat stress clothing for construction workers in hot and humid weather. Following DeJonge’s functional clothing design process, the design situation was explored, including clothing fabric heat/moisture transporting properties and UV protection and the aspects of clothing ergonomic design (mobility, convenience, and safety). The problem structure was derived from the results of the surveys in three local construction sites, which agreed well with the task requirements and observations. Specifications were consequently described and 30 commercially available fabrics were identified and tested. Fabric testing data and design considerations were inputted in S-smart system to predict the thermal functional performance of the clothing. A new uniform prototype was developed and evaluated. The results of all measurements suggest that the new uniform which incorporated fabrics with superior heat/moisture transporting properties and loose-fitting design could reduce the workers’ heat stress and improve their comfort and work performance.

Practitioner Summary:

The construction workers’ uniform currently used in Hong Kong during summer was unsatisfactory. Following DeJonge’s functional clothing design process, an anti-heat stress uniform was developed by testing 30 fabrics and predicting clothing thermal functional performance using S-smart system. The new uniform could reduce the workers’ heat stress and improve their comfort and work performance.  相似文献   


8.
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   


9.
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   


10.
The study sought to investigate whether an orthotic stiletto could modulate the pressure and comfort under the forefoot, arch and heel that stiletto wearers experience. Twenty-two women participated. We measured the peak pressure and pressure-time integral for orthotic stilettos with built-in metatarsal pad, heel cup and arch support; standard stilettos without inlays; and trainers. Comfort was recorded during 3 × 3 working days. The orthotic stiletto exhibited lower metatarsal head1 (MTH) and MTH2+3 and heel pressures than the standard stiletto (p < .01), and a long second metatarsal increased MTH2+3 pressure (p < .01). The comfort in the forefoot and heel was higher in the orthotic stiletto than in the standard one (p < .01), and comfort in the forefoot was correlated to the pressure-time integral of MTH2+3 (p = .03) and not peak pressure. Off-the-rack orthotic stilettos can notably reduce plantar pressures and improve forefoot and heel comfort during everyday use.

Practitioner Summary: Off-the-rack orthotic stilettos with built-in metatarsal pad, arch support and heel caps can lower the pressure under the heel and forefoot in comparison with a standard stiletto and can improve comfort during everyday use. Having a long second metatarsal is a risk factor for increased forefoot pressure.  相似文献   


11.
Automated driving has the potential to improve the safety and efficiency of future traffic and to extend elderly peoples’ driving life, provided it is perceived as comfortable and joyful and is accepted by drivers. Driving comfort could be enhanced by familiar automated driving styles based on drivers’ manual driving styles. In a two-stage driving simulator study, effects of driving automation and driving style familiarity on driving comfort, enjoyment and system acceptance were examined. Twenty younger and 20 older drivers performed a manual and four automated drives of different driving style familiarity. Acceptance, comfort and enjoyment were assessed after driving with standardised questionnaires, discomfort during driving via handset control. Automation increased both age groups’ comfort, but decreased younger drivers’ enjoyment. Younger drivers showed higher comfort, enjoyment and acceptance with familiar automated driving styles, whereas older drivers preferred unfamiliar, automated driving styles tending to be faster than their age-affected manual driving styles.

Practitioner Summary: Automated driving needs to be comfortable and enjoyable to be accepted by drivers, which could be enhanced by driving style individualisation. This approach was evaluated in a two-stage driving simulator study for different age groups. Younger drivers preferred familiar driving styles, whereas older drivers preferred driving styles unaffected by age.  相似文献   


12.
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   


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.
At ToSC 2019, Ankele et al. proposed a novel idea for constructing zero-correlation linear distinguishers in a related-tweakey model. This paper further clarifies this principle and gives a search model for zero-correlation distinguishers. As a result, for the first time, the authors construct 15-round and 17-round zero-correlation linear distinguishers for SKINNY-n-2n and SKINNY-n-3n, respectively, which are both two rounds longer than Anekele et al.’s. Based on these distinguishers, the paper presents related-tweakey zero-correlation linear attacks on 22-round SKINNY-n-2n and 26-round SKINNY-n-3n, respectively.  相似文献   

16.
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   


17.
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   


18.
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   


19.
Because the range of mobile robot sensors is limited and navigation maps are not always accurate, autonomous navigation in dynamic and unknown environments is a big challenge. In this article, we propose two novel autonomous navigation algorithms, which are based on the analysis of three conditions for unobserved and uncertain environments during navigation.

The algorithm for a dynamic environment uses the “known space” and “free space” conditions. It corrects false obstacles in the map when the conventional path is stuck. The navigation algorithm for unknown environments uses the “unknown space” and “free space” conditions. We use the Monte Carlo method to evaluate the performance of our algorithms and the other methods. Experimental results show that our autonomous navigation algorithms are better than the others.  相似文献   


20.
The purpose of this study is to provide a method for classifying non-fatigued vs. fatigued states following manual material handling. A method of template matching pattern recognition for feature extraction ($1 Recognizer) along with the support vector machine model for classification were applied on the kinematics of gait cycles segmented by our stepwise search-based segmentation algorithm. A single inertial measurement unit on the ankle was used, providing a minimally intrusive and inexpensive tool for monitoring. The classifier distinguished between states using distance-based scores from the recogniser and the step duration. The results of fatigue detection showed an accuracy of 90% across data from 20 recruited subjects. This method utilises the minimum amount of data and features from only one low-cost sensor to reliably classify the state of fatigue induced by a realistic manufacturing task using a simple machine learning algorithm that can be extended to real-time fatigue monitoring as a future technology to be employed in the manufacturing facilities.

Practitioner Summary: We examined the use of a wearable sensor for the detection of fatigue-related changes in gait based on a simulated manual material handling task. Classification based on foot acceleration and position trajectories resulted in 90% accuracy. This method provides a practical framework for predicting realistic levels of fatigue.  相似文献   


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