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排序方式: 共有197条查询结果,搜索用时 10 毫秒
1.
J Kongerud KI Myhre OA Hauge H Kjuus E Melbostad TB Aasen 《Canadian Metallurgical Quarterly》1996,116(6):759-763
The Norwegian Societies of Thoracic Medicine and Occupational Medicine established a working group to standardise diagnostic procedures and evaluation of work-related respiratory disorders. In cases of suspected work-related diseases the physician may be asked by the National Insurance Administration or an insurance company to make a statement which will be one of the documents used to decide the patient's right to compensation benefit. We discuss the role of the physician as an independent expert. This is different from his role as clinician. The statement should include a balanced presentation of information from different sources, including health and occupational history, and the employer's information about the work environment (quantitative and qualitative exposure data). The statement must also include the results of a clinical examination and an assessment of functional status based on objective tests. The paper contains recommendations for evaluation of permanent impairment in light of the present Norwegian laws and regulations. 相似文献
2.
In most industrialized countries, the end of the Cold War marked a change in focus from preparedness for war to an increasing focus on civil society's own vulnerability and safety. To meet new threats and changing risks, there is also a need for new analytical concepts. Societal safety is a concept developed in Norway during the last decade. It could be defined as: ‘The society's ability to maintain critical social functions, to protect the life and health of the citizens and to meet the citizens' basic requirements in a variety of stress situations’. It aims to be a systematic approach for understanding, mitigating and responding to social problems such as extraordinary stresses and losses, interferences in complex and mutual dependent systems, or lack of trust in vital social institutions. Future threats to society are not limited to specific sectors or areas, but stem from complex interactions amongst economic, technological, social and cultural factors. Thus, the main challenges to improve societal safety will be the ability to coordinate, organize and assign clear roles to different actors at the international, national and local levels. Societal safety has interfaces with other safety‐related areas such as national security, sustainable development, human security and incident management (handling of isolated accidents, common illness and ordinary criminal acts). Societal safety is, however, a sensitive political issue containing dilemmas and value choices that are hardly possible to perceive or solve as pure scientific problems. 相似文献
3.
An Operator-integration-factor splitting method for time-dependent problems: Application to incompressible fluid flow 总被引:1,自引:1,他引:0
In this paper we present a simple, general methodology for the generation of high-order operator decomposition (splitting) techniques for the solution of time-dependent problems arising in ordinary and partial differential equations. The new approach exploits operator integration factors to reduce multiple-operator equations to an associated series of single-operator initial-value subproblems. Two illustrations of the procedure are presented: the first, a second-order method in time applied to velocity-pressure decoupling in the incompressible Stokes problem; the second, a third-order method in time applied to convection-Stokes decoupling in the incompressible Navier-Stokes equations. Critical open questions are briefly described. 相似文献
4.
Feature selection is an important aspect of solving data-mining and machine-learning problems. This paper proposes a feature-selection
method for the Support Vector Machine (SVM) learning. Like most feature-selection methods, the proposed method ranks all features
in decreasing order of importance so that more relevant features can be identified. It uses a novel criterion based on the
probabilistic outputs of SVM. This criterion, termed Feature-based Sensitivity of Posterior Probabilities (FSPP), evaluates
the importance of a specific feature by computing the aggregate value, over the feature space, of the absolute difference
of the probabilistic outputs of SVM with and without the feature. The exact form of this criterion is not easily computable
and approximation is needed. Four approximations, FSPP1-FSPP4, are proposed for this purpose. The first two approximations
evaluate the criterion by randomly permuting the values of the feature among samples of the training data. They differ in
their choices of the mapping function from standard SVM output to its probabilistic output: FSPP1 uses a simple threshold
function while FSPP2 uses a sigmoid function. The second two directly approximate the criterion but differ in the smoothness
assumptions of criterion with respect to the features. The performance of these approximations, used in an overall feature-selection
scheme, is then evaluated on various artificial problems and real-world problems, including datasets from the recent Neural
Information Processing Systems (NIPS) feature selection competition. FSPP1-3 show good performance consistently with FSPP2
being the best overall by a slight margin. The performance of FSPP2 is competitive with some of the best performing feature-selection
methods in the literature on the datasets that we have tested. Its associated computations are modest and hence it is suitable
as a feature-selection method for SVM applications.
Editor: Risto Miikkulainen. 相似文献
5.
Anita Gupta Jingyue Li Reidar Conradi Harald Rønneberg Einar Landre 《Empirical Software Engineering》2009,14(2):227-255
The benefits of software reuse have been studied for many years. Several previous studies have observed that reused software
has a lower defect density than newly built software. However, few studies have investigated empirically the reasons for this
phenomenon. To date, we have only the common sense observation that as software is reused over time, the fixed defects will
accumulate and will result in high-quality software. This paper reports on an industrial case study in a large Norwegian Oil
and Gas company, involving a reused Java class framework and two applications that use that framework. We analyzed all trouble
reports from the use of the framework and the applications according to the Orthogonal Defect Classification (ODC), followed
by a qualitative Root Cause Analysis (RCA). The results reveal that the framework has a much lower defect density in total
than one application and a slightly higher defect density than the other. In addition, the defect densities of the most severe
defects of the reused framework are similar to those of the applications that are reusing it. The results of the ODC and RCA
analyses reveal that systematic reuse (i.e. clearly defined and stable requirements, better design, hesitance to change, and
solid testing) lead to lower defect densities of the functional-type defects in the reused framework than in applications
that are reusing it. However, the different “nature” of the framework and the applications (e.g. interaction with other software,
number and complexity of business logic, and functionality of the software) may confound the causal relationship between systematic
reuse and the lower defect density of the reused software. Using the results of the study as a basis, we present an improved
overall cause–effect model between systematic reuse and lower defect density that will facilitate further studies and implementations
of software reuse.
相似文献
Anita GuptaEmail: |
6.
Bin Xiao Tao Dong Einar Halvorsen Zhaochu Yang Yulong Zhang Nils Hoivik Dandan Gu Nhut Minh Tran Henrik Jakobsen 《Microsystem Technologies》2011,17(1):115-125
This paper presents the design and fabrication of a micro Pirani gauge using VO
x
as the sensitive material for monitoring the pressure inside a hermetical package for micro bolometer focal plane arrays
(FPAs). The designed Pirani gauge working in heat dissipating mode was intentionally fabricated using standard MEMS processing
which is highly compatible with the FPAs fabrication. The functional layer of the micro Pirani gauge is a VO
x
thin film designed as a 100 × 200 μm pixel, suspended 2 μm above the substrate. By modeling of rarefied gas heat conduction
using the Extended Fourier’s law, finite element analysis is used to investigate the sensitivity of the pressure gauge. Also
the thermal interactions between the micro Pirani gauge and bolometer FPAs are verified. From the fabricated prototype, the
measured device TCR is about −0.8% K−1 and the sensitivity about 1.84 × 10−3 W K−1 mbar−1. 相似文献
7.
Esther Hontañón Marcel Rouenhoff Alfredo Azabal Emilio Ramiro Frank Einar Kruis 《Aerosol science and technology》2014,48(3):333-339
An existing differential mobility analyzer (DMA) of cylindrical electrodes and a novel DMA of rectangular plate electrodes are demonstrated for size fractionation of nanoparticles at high-aerosol flow rates in this work. The two DMAs are capable of delivering monodisperse size selected nanoparticles (SMPS σg < 1.1) at gas flow rates ranging from 200 slm to 500 slm. At an aerosol flow rate of 200 slm, the maximum attainable particle mean size is of about 20 nm for the cylindrical DMA and of nearly 50 nm for the rectangular plate DMA. The number concentration of the monodisperse nanoparticles delivered by the high-flow DMAs spans from 104 cm?3 to 106 cm?3 depending upon the particle mean size and particle size dispersion.
Copyright 2014 American Association for Aerosol Research 相似文献
8.
Simpson Ian B. K. Bensted David J. Dawalibi Farid Blix Einar D. 《Industry Applications, IEEE Transactions on》1987,(3):490-497
In large plants with high primary fault levels, the whole plant must be considered as forming the ground grid for the return of primary fault current. The internal impedance of the equivalent ground grid must be taken into account in grid potential rise calculations, as grid potentials transferred from one area of the plant may cause hazardous touch potentials at other locations. Field measurements and computer analyses to calculate the distribution of grid potential rise in a large grounding system are presented. 相似文献
9.
Kinematics of the heart: strain-rate imaging from time-resolved three-dimensional phase contrast MRI
Selskog P Heiberg E Ebbers T Wigström L Karlsson M 《IEEE transactions on medical imaging》2002,21(9):1105-1109
A four-dimensional mapping (three spatial dimensions + time) of myocardial strain-rate would help to describe the mechanical properties of the myocardium, which affect important physiological factors such as the pumping performance of the ventricles. Strain-rate represents the local instantaneous deformation of the myocardium and can be calculated from the spatial gradients of the velocity field. Strain-rate has previously been calculated using one-dimensional (ultrasound) or two-dimensional (2-D) magnetic resonance imaging) techniques. However, this assumes that myocardial motion only occurs in one direction or in one plane, respectively. This paper presents a method for calculation of the time-resolved three-dimensional (3-D) strain-rate tensor using velocity vector information in a 3-D spatial grid during the whole cardiac cycle. The strain-rate tensor provides full information of both magnitude and direction of the instantaneous deformation of the myocardium. A method for visualization of the full 3-D tensor is also suggested. The tensors are visualized using ellipsoids, which display the principal directions of strain-rate and the ratio between strain-rate magnitude in each direction. The presented method reveals the principal strain-rate directions without a priori knowledge of myocardial motion directions. 相似文献
10.
Identification and analysis of wax esters by mass spectrometry 总被引:2,自引:0,他引:2
Several ions in the mass spectra of wax esters were related to the molecular structures. Assigned structures of ions were
confirmed by deuterium labeling. A simple, direct method for quantititive analyses of mixtures was developed. The method involved
a comparison of sets of three ions, RCO2H+, RCO2H2
+ and [R′−1]+ from all compounds in the mixture. The method was found applicable for mixtures of unsaturated wax esters after reduction
with tetradeuterio hydrazine.
Presented in part before the ISF-AOCS World Congress, Chicago, September 1970. Part III of a series of mass spectrometry of
lipids. For VI see Lipids. 相似文献