Publications by authors named "Jacek Jakubowski"

The steel constructions of mine shaft steelwork are particularly exposed to aggressive environments, which cause large, nonuniform corrosion loss throughout the steel members. A correct assessment of corrosion loss and load-carrying capacity of shaft steelwork is crucial for its maintenance and safe operation. In this article, we present the results of laboratory, numerical, and analytical investigations conducted on naturally corroded steel guides disassembled from shaft steelwork.

View Article and Find Full Text PDF

This paper reveals the relationships between key factors that determine the ability of cementitious composites to self-heal autogenously and specific measures for quantifying the effects of this process. The following material factors: water-to-binder ratio (w/b), uniaxial compressive strength and age of the composite at the time of defect formation were considered, as well as the method and degree of damage to the tested material. The subjects of this study were mortars and concretes in which Portland cement was partially replaced, to varying degrees, with mechanically activated fluidized bed combustion fly ash (MAFBC fly ash) and siliceous fly ash.

View Article and Find Full Text PDF

The self-sealing process, associated with chemical and microstructural changes inside damaged cement-based composites, leads to the recovery of the original material integrity. Assessing the magnitude of internal changes in samples using non-destructive techniques to capture only the self-sealing effects is difficult. The challenge is evaluating the differences between subsequent observations in time and between samples with different properties.

View Article and Find Full Text PDF

This article proposes a novel framework for the locally-oriented evaluation of segmentation algorithms (LEFMIS). The presented approach is robust and takes into account local inter/intra-observer variability and the anisotropy of medical images. What is more, the framework makes it possible to distinguish types of error locally.

View Article and Find Full Text PDF

Unlabelled: The right kidney cancer very rarely locally invades the liver as compared with blood metastasis which occur more frequent. In these cases, the only extensive surgical resection of part of the liver gives the opportunity to improve survival dependent on kidney cancer. In the intra-and postoperative bleeding and leakage of bile from the liver cut surface is a complication that it depends on the success of the treatment.

View Article and Find Full Text PDF

Introduction: The clinical course of renal cancer remains difficult to predict. Attempts to appoint new independent prognostic factors (IPFs) and comparisons of already identified ones among populations are inevitable to develop more effective prognostic instruments. The aim of this study was to evaluate IPFs of overall survival in a given population of patients with renal cancer.

View Article and Find Full Text PDF

Background: Based on a 11-year implementation of the Amiantus Project, this paper reports the results of prophylactic medical examinations of the former workers of asbestos processing plants. The Project involving employees of 28 former asbestos plants was started by the Ministry of Health in 2000 under the Act on the ban of all products containing asbestos.

Material And Methods: Preventive examinations, continued in 13 centers of occupational medicine throughout the whole territory of Poland, have been coordinated by the Nofer Institute of Occupational Medicine in Lodz (NIOM).

View Article and Find Full Text PDF

The paper presents a new approach to the computer aided diagnostic systems for the needs of quantitative electromyography. The approach is based on the analysis of wavelet scalograms of the motor unit action potentials calculated on the basis of 4th order Symlet wavelet. The scalograms provide the vector consisting of six features describing the state of a muscle that can be reduced to the two features with use of Linear Discriminant Analysis.

View Article and Find Full Text PDF

Background: Prophylactic examinations of workers formerly employed in asbestos processing plants were performed by virtue of the Act, dated 19 June 1997, putting a ban on the production of asbestos-containing products. To enforce the provisions of the Act, the Ministry of Health has initiated the Amiantus project implemented by 13 Occupational Medicine Centers throughout the country and coordinated by the Nofer Institute of Occupational Medicine (IMP) in Lódź.

Material And Methods: All the Centers perform diagnostic procedures according to the same criteria (clinical, radiological, spirometric and histological), based on the 1997 Helsinki criteria, to diagnose asbestos-related diseases.

View Article and Find Full Text PDF

This paper is concerned with the tremor characterization for the purpose of recognition. Three different types of tremor are considered in this paper: the parkinsonian, essential, and physiological. It has been proven that standard second-order statistical description of tremor is not sufficient to distinguish between these three types.

View Article and Find Full Text PDF