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1.
《Ergonomics》2012,55(8):1461-1469
Heat stress caused by protective clothing limits work time. Performance improvement of a microclimate cooling method that enhances evaporative and to a minor extent convective heat loss was tested. Ten male volunteers in protective overalls completed a work-rest schedule (130 min; treadmill: 3 × 30 min, 3 km/h, 5% incline) with or without an additional air-diffusing garment (climatic chamber: 25°C, 50% RH, 0.2 m/s wind). Heat loss was supported by ventilating the garment with dry air (600 l/min, ?5% RH, 25°C). Ventilation leads (M ± SD, n = 10, ventilated vs. non-ventilated) to substantial strain reduction (max. HR: 123 ± 12 b/min vs. 149 ± 24 b/min) by thermal relief (max. core temperature: 37.8 ± 0.3°C vs. 38.4 ± 0.4°C, max. mean skin temperature: 34.7 ± 0.8°C vs. 37.1 ± 0.3°C) and offers essential extensions in performance and work time under thermal insulation. 相似文献
2.
《Ergonomics》2012,55(9):709-720
Abstract Interline flicker is generally most noticeable in small high luminance areas and at high contrast transitions occurring across the television line structure. A subjective experiment was conducted to determine the impairment arising from interline flicker for simple counterphase rectangular patterns whose width and height was varied. A rapid dimunition in picture quality was found to occur as soon as the counterphase format of the pattern (corresponding to the line structure) became readily discernible. Possible methods of reducing the visibility of interline flicker are discussed. 相似文献
3.
V. A. Yatsko 《Automatic Documentation and Mathematical Linguistics》2012,46(2):112-117
This paper suggests interpreting Bradford’s law in terms of a geometric progression; it introduces a constant, which allows simplifying the application of the law, and outlines the methodology for using the law to analyze the data related to various subject areas. 相似文献
4.
In this paper, we give characterizations of ordered semigroups in terms of (∈, ∈ ∨q)-fuzzy interior ideals. We characterize different classes regular (resp. intra-regular, simple and semisimple) ordered semigroups
in terms of (∈, ∈ ∨q)-fuzzy interior ideals (resp. (∈, ∈ ∨q)-fuzzy ideals). In this regard, we prove that in regular (resp. intra-regular and semisimple) ordered semigroups the concept
of (∈, ∈ ∨q)-fuzzy ideals and (∈, ∈ ∨q)-fuzzy interior ideals coincide. We prove that an ordered semigroup S is simple if and only if it is (∈, ∈ ∨q)-fuzzy simple. We characterize intra-regular (resp. semisimple) ordered semigroups in terms of (∈, ∈ ∨q)-fuzzy ideals (resp. (∈, ∈ ∨q)-fuzzy interior ideals). Finally, we consider the concept of implication-based fuzzy interior ideals in an ordered semigroup,
in particular, the implication operators in Lukasiewicz system of continuous-valued logic are discussed. 相似文献
5.
《Information Storage and Retrieval》1967,3(2):35-116
Analyses of the language used by chemists and biochemists have been made and a classification of vocabularies suggested. There are three main types of vocabulary involved—(i) a basic vocabulary common to the majority of experimental scientific disciplines, (ii) taxonomic vocabularies for each sub-discipline, which are essentially the names of forms and systems of matter, and (iii) specific vocabularies embodying the so-called “jargon” or specialized terms of each sub-discipline. Examples of each are given and their interactions and uses discussed; suggestions are made for the formation of a general scheme of scientific word-lists for computer use. 相似文献
6.
M. TAROKH 《International journal of control》2013,86(5)
This note briefly discusses the results of a recent paper by Wang et al. (1987) on the characterization of decentralized fixed modes. It is concluded that these results have already been obtained by Tarokh (1985). 相似文献
7.
Using Students as Subjects—A Comparative Study of Students and Professionals in Lead-Time Impact Assessment 总被引:4,自引:4,他引:0
In many studiesin software engineering students are used instead of professionalsoftware developers, although the objective is to draw conclusionsvalid for professional software developers. This paper presentsa study where the difference between the two groups is evaluated.People from the two groups have individually carried out a non-trivialsoftware engineering judgement task involving the assessmentof how ten different factors affect the lead-time of softwaredevelopment projects. It is found that the differences are onlyminor, and it is concluded that software engineering studentsmay be used instead of professional software developers undercertain conditions. These conditions are identified and describedbased on generally accepted criteria for validity evaluationof empirical studies. 相似文献
8.
Alexey E. Rastegin 《Quantum Information Processing》2013,12(9):2947-2963
Uncertainty relations for more than two observables have found use in quantum information, though commonly known relations pertain to a pair of observables. We present novel uncertainty and certainty relations of state-independent form for the three Pauli observables with use of the Tsallis $\alpha $ -entropies. For all real $\alpha \in (0;1]$ and integer $\alpha \ge 2$ , lower bounds on the sum of three $\alpha $ -entropies are obtained. These bounds are tight in the sense that they are always reached with certain pure states. The necessary and sufficient condition for equality is that the qubit state is an eigenstate of one of the Pauli observables. Using concavity with respect to the parameter $\alpha $ , we derive approximate lower bounds for non-integer $\alpha \in (1;+\infty )$ . In the case of pure states, the developed method also allows to obtain upper bounds on the entropic sum for real $\alpha \in (0;1]$ and integer $\alpha \ge 2$ . For applied purposes, entropic bounds are often used with averaging over the individual entropies. Combining the obtained bounds leads to a band, in which the rescaled average $\alpha $ -entropy ranges in the pure-state case. A width of this band is essentially dependent on $\alpha $ . It can be interpreted as an evidence for sensitivity in quantifying the complementarity. 相似文献
9.
Based on various kinds of experimental diffusivities and thermodynamic parameters available in the literature, the atomic mobilities of Al and Cu in face-centered cubic (fcc) Al–Cu alloys have been assessed as a function of temperature and composition by means of DIffusion Controlled TRAnsformation (DICTRA) software package. Comprehensive comparisons between the calculated and measured diffusivities show that most of the experimental data can be well reproduced by the presently obtained atomic mobilities. In addition, the atomic mobilities obtained in the present work can also reasonably predict the concentration profiles for a variety of diffusion couples in fcc Al–Cu alloys including the one prepared in the present work. 相似文献
10.
《Computational statistics & data analysis》1987,5(1):23-30
The power of a test for no three way interaction in 2 × J × K tables, performed by partitioning the K strata into two groups was investigated by simulation. Mantel-Haenszel estimation techniques were used to calculate the test statistic. The power was compared with that of Pearson's X2 and the likelihood ratio G2. The partition test had substantially greater power than either X2 or G2 in cases most favorable to the partition test and somewhat greater power for cases moderately favorable to it. The greater power can be explained by the smaller degrees of freedom for the partition test (J − 1 vs (J − 1)(K − 1) for X2 and G2). The results also suggest that the distribution of the test statistic more closely follows a non-central chi square distribution in non-null cases for the partition test. If an appropriate partitioning of the strata can be made, the partitioning test would be preferable to the widely used X2 and G2 tests. 相似文献
11.
《Advances in Engineering Software (1978)》1981,3(4):155-162
FASOR (Field Analysis of Shells of Revolution) is a user-oriented code for the analysis of stiffened, laminated axisymmetric shells. Very general shell geometries are allowed in that the reference surface meridian may form a branched, multi-circuit figure. Modes of response treated are linear asymmetric and geometrically nonlinear axisymmetric prebuckling, and asymmetric buckling and vibration under static axisymmetric loads. Bifurcation buckling under asymmetric loads is also treated by using a symmetrized prebuckling state based on the linear response of a user-specified meridian. For each mode of response, the user may specify any combination of orthotropic or anisotropic material properties with classical or transverse shear deformation shell theories.FASOR employs a numerical integration method (called the field method) whereby a numerically unstable linear boundary-value problem (all modes of response reduce to a sequence of such problems) is converted into two successive numerically stable initial-value problems. In this context, numerical stability means that round-off errors introduced at each step of the integration process tend to decay out. As a consequence, solution accuracy is controlled essentially by a single number, the truncation error tolerance, which is satisfied by automatically adjusting the size of each integration step. The field method thus eliminates the need for mesh generation required by finite element and finite difference methods, and the associated problem of numerical convergence. It also provides for automatic determination of response storage points so as to obtain a uniformly valid discrete approximation of the continuous response.In this paper the field method is briefly described, basic aspects of the mathematical model are discussed, the organization of input data is presented, and input and plot output are given for specific examples. 相似文献
12.
This paper proposes a novel training algorithm for radial basis function neural networks based on fuzzy clustering and particle swarm optimization. So far, fuzzy clustering has proven to be a very efficient tool in designing such kind of networks. The motivation of the current work is to quantify the exact effect of fuzzy cluster analysis on the network’s performance and use it in order to substantially improve this performance. There are two key theoretical findings resulting from the present work. First, it is analytically proved that when the standard fuzzy c-means algorithm is used to generate the input space fuzzy partition, the main effect this partition imposes to the network’s square error (i.e. performance index) can be written down in terms of a distortion function that measures the ability of the partition to recreate the original data. Second, using the aforementioned distortion function, an upper bound of the network’s square error can be constructed. Then, the particle swarm optimization (PSO) is put in place to minimize the above upper bound and determine the network’s parameters. To further improve the accuracy, the basis function widths and the connection weights are fine-tuned by employing a steepest descent approach. The main experimental findings are: (a) the implementation of the PSO obtains a significant reduction of the square error while exhibiting a smooth dynamic behavior, (b) although the steepest descent further decreases the error it finally obtains smaller reduction rates, meaning that the strongest impact on the error reduction is provided by the PSO, and (c) the improved performance of the proposed network is demonstrated through an extensive comparison with other related methods using a 10-fold cross-validation analysis. 相似文献
13.
Aleksey Pavlovich Anisimov Anatoly Jakovlevich Ryzhenkov Dmitriy Vladimirovich Kozhemyakin 《Information & Communications Technology Law》2015,24(1):104-117
With the development of the Internet, more people are creating personal websites and blogs, and they expect to be able to use their own name or surname in the domain name. The aim of this article is to identify and analyse the existing problems in the use and protection of personal names in the domain space, as well as the development of legal approaches that can be used to resolve disputes that arise. In the course of the analysis, the authors conclude that the existing legal regulations at both the international and national levels are not sufficient to protect personal names effectively. Current approaches in this area are scattered and not systematic. The conclusions and suggestions made in this paper can be used to form a specialised procedure to resolve domain name disputes relating to personal names, as well as in the course of organising and updating the national legislations of the states of Eastern Europe. 相似文献
14.
15.
Heterogeneous (or hybrid) computing platforms with Intel Xeon Phi accelerators offer potential advantages of energy efficient, massively parallel computing, while supporting parallel programming models familiar for users of multicore CPUs. However, realizing this potential for real-world applications still remains a challenging issue. The main goal of this paper is the suitability assessment of offload-based programming environments for porting a real-life scientific application to hybrid platforms with Intel KNC and KNL accelerators, assuming no significant modifications of the application code. The main criterion of this assessment is the application performance. The evaluated environments include: 1) Intel Offload coupled with OpenMP, 2) OpenMP 4.0 and 3) OpenMP 4.5 Accelerator Models, and 4) hStreams Library with OpenMP. A real-life application dedicated to the numerical modeling of alloy solidification is used as a testbed in the assessment. An experimental evaluation of the four versions of the application code for a platform with KNC coprocessors shows that excluding OpenMP 4.0, the rest of them are able to adapt to expansion of available resources, however, with different efficiency. While the shortest execution time is achieved for Intel Offload, the high-level abstractions of hStreams contribute considerably to making porting and tuning the application easier, with low performance overheads in comparison to the low-level Intel Offload extension. Benchmarking the application performance and scalability on a platform with multiple KNL processors, using the Offload over Fabric technology with Intel Offload and OpenMP 4.5, concludes the assessment. 相似文献
16.
Weibin Zhang Yong Du Dongdong Zhao Lijun Zhang Honghui Xu Shuhong Liu Yiwei Li Shuquan Liang 《Calphad》2010
Various experimentally measured diffusivities of fcc Al–Mg, Cu–Mg and Al–Cu–Mg alloys available in the literature are critically reviewed in the present work. The first-principles calculations coupled with a semi-empirical correlation is employed to derive the temperature dependence of impurity diffusivity for Mg in fcc Cu. Atomic mobilities for the above fcc alloys are then evaluated as a function of temperature and composition by means of DICTRA (DIffusion Controlled TRAnsformation) software. Comprehensive comparisons between calculated and measured diffusivities show that most of the experimental data can be well reproduced by the presently obtained atomic mobilities. The concentration profiles and diffusion paths are predicted with the mobility parameters in a series of binary and ternary diffusion couples. A good agreement is obtained between experiment and simulation. 相似文献
17.
Christian Nansen Tulio Macedo Rand Swanson David K. Weaver 《International journal of remote sensing》2013,34(10):2447-2464
Wheat plants were experimentally infested with wheat stem sawflies, and hyperspectral images (reflectance range from 402.8–838.7 nm) were collected from leaves of infested and non‐infested plants. Mean and variance reflectance per leaf were calculated in five of 213 spectral bands (452, 553, 657, 725, and 760 nm) and compared with vegetation indices (NDVI, SI and PRI), and standard variogram parameters (nugget, sill and range values). Mean reflectance values and their variance values and vegetation indices showed significant effects of sawfly infestation in one dataset but not in another. Based on directional variogram analyses, we showed that: (1) better separation of leaf type and infested/non‐infested wheat plants was seen in variograms in longitudinal direction compared to transverse; (2) mainly spectral bands in the red edge and NIR showed consistent effect of sawfly infestation; (3) range values were not affected significantly by either sawfly infestation or leaf type; and (4) sawfly‐induced stress was most likely to be detected about three weeks after infestation. Variogram analysis is one of the key standards in quantitative spatial ecology, and this study supports further research into its use in remote sensing with particular emphasis on detection of biotic stress. 相似文献
18.
This paper presents a new map joining algorithm and a set of metrics for evaluating the performance of mapping techniques. The input to the new map joining algorithm is a sequence of local maps containing the feature positions and the final robot pose in a local frame of reference. The output is a global map containing the global positions of all the features but without any robot poses. The algorithm is built on the D-SLAM mapping algorithm (Wang et al. in Int. J. Robot. Res. 26(2):187–204, 2007) and uses iterations to improve the estimates in the map joining step. So it is called Iterated D-SLAM Map Joining (I-DMJ). When joining maps I-DMJ ignores the odometry information connecting successive maps. This is the key to I-DMJ efficiency, because it makes both the information matrix exactly sparse and the size of the state vector bounded by the number of features. 相似文献
19.
Peter Klüger 《自动化博览》2004,21(4):15-20
1 Foreword Do we really need Ethernet in the production of tomorrow? I think, the answer is YES. The production technology of today has to meet the challenge to develop new strategies for a highly flexible, highly available and cost-effective automation technology. Through the gradual increase of Ethernet technology in the automation field industrial communication could be standardized considerably to deal with all the requirements of future automation and production strategies. Industria… 相似文献
20.
One of the most important characteristics of chance discovery is that it focuses on the specific events or patterns in which
the essential nature of an applied domain is implicitly included. The understanding and forecasting of such patterns and events
will have a significant impact on decision making in the applied domain. This paper discusses the meaning of chance discovery
from the viewpoint of medicine. Since chance discovery in medicine can be viewed as the way to find a suitable occasion for
some critical actions or to check the dangerous possibilities, called rare risky events, detection and interpretation of rare
but important events are ones of the components that supports chance discovery. According to this observation, several approaches
for detecting rare events were introduced and evaluated by a small dataset on neurological diseases. Experimental results
show that a set of events which include rare risky events can be detected by the introduced detection method, though interpretation
by domain experts is required for selection of such events.
Shusaku Tsumoto, Ph.D.: He graduated from Osaka University, School of Medicine in 1989. After residents of neurology in Chiba University Hospital,
he was involved in developing hospital information system in Chiba University Hospital. He moved to Tokyo Medical University
in 1993 and started his research on rough sets and data mining in medicine. He received his Ph.D (Computer Science) from Tokyo
Institute of Technology in 1997, and is now a Professor at Department of Medical Informatics, Shimane Medical University.
His interests include approximate reasoning, data mining, fuzzy sets, knowledge acquisition, mathematical theory of data mining,
and rough sets (alphabetical order). 相似文献