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A correctly designed machine is characteristic of low vibration values. However wear processes occur during its operation. They are accompanied by a lack of balance of its rotating parts and elements, which results in non-coaxiality of shafts. For this reason energy and dynamic load resulting from machine vibrations grows. In this case cause and effect are mutually connected by feedback, that inevitably leads to occurrence of a failure. This paper presents results of investigations carried out on the basis of vibration analysis of propulsion systems installed on 207P minesweepers. In view of specific features of their operation it is very important to ensure high level of reliability for them. For this reason was done an attempt to develop a method intended for identifying non-coaxiality of shaft line systems of engines propelling the ships. 16 characteristic features of recorded vibration signals were selected. As any of them has not satisfied criteria assigned to features which unambiguously determine state of reliability of shaft line systems, the investigations have been continued and as a result a novel method for non-coaxiality identification was proposed. The method consists in determining unserviceability clusters and assumes that characteristic features are of a concentrated character. This way a non-coaxiality of main engine shaft lines of 207P minesweepers could be detected. This paper presents the proposed method and results of its application to the case in question
W pracy dokonano szacunkowej ocena pobrania azotanów(V) i azotanów(III) z żywnością w gospodarstwach domowych w Polsce w latach 1996–2005. Wykazano, że pobranie azotanów(V) i azotanów(III) z żywnością w badanych typach gospodarstw domowych było stosunkowo niskie i nie przekraczało ustalonej wartości ADI, wynosząc 132–190 mg NaNO3/osobę/dzień (56,8% ADI), oraz od 3,0 do 3,5 mg NaNO2/osobę/dzień (58% ADI). Głównym źródłem azotanów(V) były warzywa, które wnosiły do diety średnio 89% ogólnej ich ilości, azotany(III) w blisko 69% pochodziły z mięsa i przetworów mięsnych.
Nasięźrzał pospolity Ophioglossum vulgatum L., znany był dotychczas z dwóch stanowisk na Płaskowyżu Kolbuszowskim. W latach 2008 i 2015 odkryto trzy nowe stanowiska w miejscowościach Wólka Niedźwiedzka-Budy (ATPOL FF46) oraz Nart i Poręby Wolskie (ATPOL FF34). Najliczniej nasięźrzał występował w miejscowości Nart - na powierzchni ok. 3 m2 zagęszczenie wynosiło około 40 osobników na 1 m2.
This article deals with the modeling of the processes of operating both marine main and auxiliary engines. The paper presents a model of changes in operating conditions of ship’s internal combustion engine. The semi-Markov decision process was used to mathematically describe the process model of the engine. The developed model describes the effect of engine damage on the characteristics of its operation.A change in the input parameters of the model can simulate the influence of internal and external factors on the course of the analyzed process. A simplified calculation example is also presented for illustration purposes.The presented method together with developed algorithms and IT tools can be used to solve a wide range of problems related to the operation of marine main engines and other marine equipment as well as maritime and port facilities. This concerns primarily the economic, risk management and operational security issues of complex technical systems, as well as the readiness and reliability analysis of technical facilities
Ship large-power steam boiler may serve as an example of complex critical technical system. A basis for rational control of operation of such system is knowledge on its capability of fulfilling the tasks to which it was intended. In order to make it possible to apply computer aiding to operational decision-making the capability should be described analytically. In this paper it was proposed to express the capability of ship steam boiler ( considered a complex system) to perform service tasks, by calculating components of its usability potential in a given instant t. To this end , was distinguished a set of steam boiler fundamental features which formulate space of its technical states. Values and characteristic intervals of the features were defined and this way sub-spaces of serviceability and non-serviceability states of the object in question were determined. Next, in the considered space, technical state of the boiler and its usability potential was determined. Owing to this it become possible to quantitatively express the steam boiler functioning capability which served as a basis for elaborating an algorithm for controlling the operational processes of a complex technical system under action. In this paper is also described a way of application of the presented method to calculation of ship steam boiler usability potential, which may be especially instrumental in the case of operational control of the boilers of the kind , equipped with interstage reheaters, i.e. those operating with high values of operational parameters
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