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71.
During the first ten months of 1992 the Oslo Ambulance Department registered 716 incidences of assumed drug-related intoxications. 80% happened in down town Oslo. 19 cases of asystoly were recorded, 13 of the patients recovered after treatment, without sequelae. Five of these patients left the location after emergency help and they refused hospitalization. 432 of the patients were unconscious when the ambulance personal arrived, 472 were treated with naloxone both by the intramuscular and the intravenous route. Most of the persons refused further observation. A team of specially trained out reach workers offers help after acute medical treatment by means of "streetwork". The intervention is directed at addicts who have experienced an overdose. 相似文献
72.
K. M. Itoh W. L. Hansen J. W. Beeman E. E. Haller J. W. Farmer V. I. Ozhogin 《Journal of Low Temperature Physics》1993,93(3-4):307-312
The temperature dependence of variable range hopping resistivity in neutron transmutation doped (NTD) isotopically enriched70Ge:Ga samples is reported. Five samples with compensation ratios K less than 0.001 and Ga concentrations between 3×1016 and 1.77×1017 cm–3 were studied. All samples investigated show the ln T–1/2 dependence in the temperature range below 1.5K. As thermistor materials NTD70Ge:Ga samples are found to have more than factor of two higher sensitivity than commonly used natural NTD Ge in the temperature range between 0.2K and 1K. Our results are compared with theoretical predictions for variable range hopping conduction. 相似文献
73.
Bicriterion cluster analysis 总被引:1,自引:0,他引:1
Delattre M Hansen P 《IEEE transactions on pattern analysis and machine intelligence》1980,(4):277-291
Cluster analysis is concerned with the problem of partitioning a given set of entities into homogeneous and well-separated subsets called clusters. The concepts of homogeneity and of separation can be made precise when a measure of dissimilarity between the entities is given. Let us define the diameter of a partition of the given set of entities into clusters as the maximum dissimilarity between any pair of entities in the same cluster and the split of a partition as the minimum dissimilarity between entities in different clusters. The problems of determining a partition into a given number of clusters with minimum diameter (i.e., a partition of maximum homogeneity) or with maximum split (i.e., a partition of maximum separation) are first considered. It is shown that the latter problem can be solved by the classical single-link clustering algorithm, while the former can be solved by a graph-theoretic algorithm involving the optimal coloration of a sequence of partial graphs, described in more detail in a previous paper. A partition into a given number of clusters will be called efficient if and only if there exists no partition into at most the same number of clusters with smaller diameter and not smaller split or with larger split and not larger diameter. Two efficient partitions are called equivalent if and only if they have the same values for the split and for the diameter. 相似文献
74.
Normalized cut is one of the most popular graph clustering criteria. The main approaches proposed for its resolution are spectral clustering methods and a multilevel approach of Dhillon et al. (TPAMI 29:1944–1957, 2007), called graclus. Their aim is to obtain good solutions in a small amount of time for large instances. Metaheuristics are general frameworks for stochastic searches often employed in global optimization to improve the solutions obtained by other heuristics. Variable neighborhood search (VNS) is a metaheuristic which exploits systematically the idea of neighborhood change during the search. In this paper, we propose a VNS heuristic for normalized cut segmentation. Computational experiments show that in most cases this VNS heuristic improves significantly, and in moderate time, the solutions obtained by the current state-of-the-art algorithms, i.e., graclus and a spectral method proposed by Yu and Shi (ICCV, 2003). 相似文献
75.
Vincent Verhaert Hans Druyts Dorien Van Deun Vasileios Exadaktylos Johan Verbraecken Marie Vandekerckhove Bart Haex Jos Vander Sloten 《International Journal of Industrial Ergonomics》2012,42(5):489-498
This study aims at evaluating spinal alignment during sleep by combining personalized human models with mattress indentation measurements. A generic surface model has been developed that can be personalized based on anthropometric parameters derived from silhouette extraction. Shape assessment of the personalized surface models, performed by comparison with 3-D surface scans of the trunk, showed a mean unsigned distance of 9.77 mm between modeled and scanned surface meshes. The surface model is combined with an inner skeleton model, allowing the model to simulate distinct sleep postures. An automatic fitting algorithm sets the appropriate degrees of freedom to position the model on the measured indentation according to the adopted sleep posture. Validation on lateral sleep positions showed good intraclass correlations (0.73–0.88) between estimated and measured angular spinal deformations, indicating that silhouette-derived body shape models provide a valuable tool for the unobtrusive assessment of spinal alignment during sleep.Relevance to industry: A common drawback of the available techniques to assess spinal deformation on bedding systems is that they interfere with the actual sleep process. The current study presents a novel method based on silhouette-derived body shape models in order to estimate spine shape during sleep unobtrusively. 相似文献
76.
Rasmussen CD Jørgensen MB Carneiro IG Flyvholm MA Olesen K Søgaard K Holtermann A 《Ergonomics》2012,55(2):256-264
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group. 相似文献
77.
Jørgensen MB Faber A Jespersen T Hansen K Ektor-Andersen J Hansen JV Holtermann A Søgaard K 《Ergonomics》2012,55(7):762-772
This study evaluates the implementation of physical coordination training (PCT) and cognitive behavioural training (CBTr) interventions in a randomised controlled trial at nine cleaners' workplaces. Female cleaners (n = 294) were randomised into a PCT, a CBTr or a reference (REF) group. Both 12-week interventions were performed in groups guided by an instructor. Records were kept on intervention dose (adherence) unanticipated events at the work place (context) and quality of intervention delivery (fidelity). Participant adherence was 37% in the PCT and 49% in the CBTr interventions. Optimal implementation was reached by only 6% in PCT and 42% in the CBTr. Analysis of the barriers to successful implementation indicated that the intervention process is sensitive to unanticipated events. In order to succeed in improving the health of high-risk populations such as cleaners and to correctly interpret intervention effects, more research on implementation is needed. Trial registration: ISRCTN96241850. PRACTITIONER SUMMARY: Both physical coordination training and cognitive behavioural training are potential effective workplace interventions among low educated job groups with high physical work demands. However, thorough consideration should be given to feasibility in the design of interventions. The optimal intervention should be tailored to closely match the implementation context and be robust and flexible to minimise susceptibility to changes in work organisation. 相似文献
78.
Questions S. L. Bem's (see record 1983-21087-001) definition of a gender schema and argues that male and female sex-typed individuals do not have equivalent gender schemata. The high-androgynous individuals are the only ones for whom both masculinity and femininity are equally available and who might be properly termed "gender schematic." (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
G. Ramadorai M. E. Wadsworth C. K. Hansen 《Metallurgical and Materials Transactions B》1975,6(4):579-584
Powdered molybdenum dioxide was oxidized to MoO3 in the temperature range 390 to 465°C under oxygen partial pressures of 0.016 and 0.18 atmospheres* and under 0.009 atmospheres in the temperature interval 465 to 529°C. The course of the reaction was followed by observing weight change with time. Parabolic kinetics were evident for oxidation below 460°C. Above 460°C linear kinetics were observed. The partial pressure dependence at 407°C and 455°C was found to be approximately \(P_{O_2 }^{1/5} \) . Oxidation tests were restricted to an oxygen partial pressure of 0.009 atmosphere in the temperature range between 460°C and 530°C since above this partial pressure excessive heating occurred. For the low temperature range the oxidation was explained in terms of the diffusion of mono-and divalent oxygen interstitials. Activation enthalpies of 159±8 and 105±8 kJ/mole were obtained respectively for parabolic and linear rate processes. 相似文献
80.
Two-way grillage or waffle floors are used extensively in semiconductor factories as they provide high impedance mounts for manufacturing equipment that is extremely vibration sensitive. This paper presents a mathematical model for the analysis of vibration at the center of a bay and the transmission of vibration along a waffle floor. The mathematical model is compared with finite element models and experimental results from several manufacturing buildings, and shows good agreement. Trends are shown for the displacement and resonance frequency of the floor as the thickness of the floor, size of the bays and the stiffness of the columns are varied. 相似文献