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1

An algorythm for preliminary estimating hull stucture mass and mass centre height of inland navigation ships

100%
Michalski J. P.
Polish Maritime Research
|
2005
|
tom 12
|
nr 1
The paper presents an algorithm for preliminary calculation of mass and mass centreheight of hull structure of inland navigation ships. It was elaborated basing on require-ments of the Rules for the Classification and Construction of Inland Navigation Ships ofPolish Register of Shipping, with application of a simplified method of estimating mass ofhull plating stiffeners. The algorithm deals with the dimensioning of scantlings of structuralmembers of classical ships intended for shipping dry cargo, and dry and liquid bulk cargo-es; however it does not cover ships of entirely different structural arrangement such as roll--on-roll-off ships fitted with heavy decks, as the dimensioning of their scantlings is based on different models
2

A method of predicting main propulsion power for inland waterways push trains

100%
Michalski J. P.
Polish Maritime Research
|
2006
|
nr Special Issue S2
This paper presents a method of predicting effective power demand (brake horse power – B.H.P.) for propulsion of inland waterways push train, useful in the preliminary design stages. By using it, on the basis of known main particulars of a given push train, i.e. its length, breadth, draught and speed, a generalized Admiralty formula can be determined and then the pusher propulsion power can be preliminarily predicted by making use of the elaborated structure of the formula. Application of the method is illustrated on the example of a two-segment push train of inland waterways passenger ship designed in the frame of the Eureka INCOWATRANS E!3065 project
3

Parametric method for evaluating optimal ship deadweight

100%
Michalski J. P.
Polish Maritime Research
|
2014
|
tom 21
|
nr 2
The paper presents a method of choosing the optimal value of the cargo ships deadweight. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper ship for a given transportation task. The deadweight is determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate (RFR). The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the pre-investment ships designing parameters simulation or transportation task studies
4

A method for selection of parameters of ship propulsion system fitted with compromise screw propeller

100%
Michalski J. P.
Polish Maritime Research
|
2007
|
tom 14
|
nr 4
This paper concerns an algorithmic method for preliminary selection of parameters of ship propulsion system fitted with fixed screw propeller in the case when the ship’s operation isassociated with significantchangesofwaterwaydepthandwidth,hullresistanceoftheshipand its service speed. Mathematical model arguments of the considered design problem are main ship design parameters identified in the preliminary design stage. Structure of theformulated model complies with formal requirements for continuous- discrete mathematical optimization problems. The presented examples of application of the method concern an inland waterways ship fitted with compromise screw propeller optimized in the sense of minimization offuel consumption for passing a given route distance within a given time. The elaborated method may be especially useful in designing such ships as : coasters, inland waterways ships, tugs, pushers, trawlers, mine sweepers, icebreakers etc
5

Preliminary designing method of external pressure vessels for sea subsurface applications

100%
Michalski J. P.
Polish Maritime Research
|
2010
|
tom 17
|
nr 2
This paper describes a unique engineering method intended for the preliminary designing of marine echo-location systems. The solved designing problem consists in determining geometrical parameters and selecting structural materials for a vessel of a buoyancy necessary to contain measuring instruments of a given mass, as well as its maximum gabarites and operational submersion depth. The assumed variability range of the system’s parameters determines a space of permissible applicability parameters of the method. Stress level related to permissible and critical stresses was assumed to be safety criterion for the vessel. The method may be applied also to solving converse problems consisting in determining maximum permissible submersion depth for a vessel made of assumed structural materials and having given geometrical parameters. The presented description of the method is illustrated by an example of its application
6

Parametrical method for determining optimal ship carrying capacity and performance of handling equipment

100%
Michalski J. P.
Polish Maritime Research
|
2016
|
tom 23
|
nr 2
The paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate. The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the preliminary ship design or in the simulation of pre-investment transportation task studies
7

A parametric method for preliminary determining of mass characteristics of inland navigation ships

100%
Michalski J. P.
Polish Maritime Research
|
2005
|
tom 12
|
nr 3
This paper presents a method for estimation of mass characteristics of vessels, elaboratedwith the use of an algorithm based on requirements of the Rules for the Classification andConstruction of Inland Waterways Vessels of Polish Register of Shipping, and on a simpli-fied method [6] for determination of mass of hull plating stiffeners. The dimensioningmethod of hull structure scantlings based on this algorithm concerns classical vesselsintended for the carrying of general cargo, dry and liquid bulk cargoes, which determinethe range of the method application. The method does not cover vessels of different construction, e.g. roll-on-roll-off type vessels equipped with heavy decks, as the dimensioning of their scantlings is based on different relationships and models
8

Parametric method applicable in calculating breakout force and time for lifting axisymetric objects from seabed

100%
Michalski J. P.
Polish Maritime Research
|
2019
|
tom 26
|
nr 3
The issue of calculating parameters for lifting objects of axisymmetric shapes from the seabed is studied. The article presents the results of numerical simulation examination of the equation formulated by Foda for the force needed to extricate the object from the seabed depending on soil and water parameters, extrication speed, and object diameter. The simulations were performed within the range of parameters characteristic for real applications, and their results were used for deriving approximate algebraic formulas applicable in engineering practice of lifting objects resting on seabed
9

Parametric method for determination of motion characteristics of underwater vehicles, applicable in preliminary designing

100%
Michalski J. P.
Polish Maritime Research
|
2009
|
tom 16
|
nr 2
This paper describes a method for preliminary designing the autonomous underwater vehicles (AUV), especially useful in the case when requirements concerning kinematic and dynamic parameters of vehicle motion are given in design assumptions. Concept of the method is based on dynamic equations which describe vehicle planar motion in vertical and horizontal directions, resulting from action of screw propellers or water ballast, respectively. The motion equations were determined by applying simplifications concerning both geometrical description of vehicle’s form and flow phenomena. Their solutions were obtained in the form of closed analytical expressions which are both of cognitive and practical merits as they can serve to assess influence of vehicle’s design parameters on its motion characteristics and simultaneously are convenient to formulate design optimization problems. Application of the method was illustrated by the attached examples dealing with determination of kinematic and dynamic characteristics of motion of the vehicle „Scylla” of set geometrical configuration and propulsion parameters
10

Arametric method applicable in assessing breakout force and time for lifting slender bodies from seabed

100%
Michalski J. P.
Polish Maritime Research
|
2020
|
tom 27
|
nr 2
11

A parametric method for evaluation of resistance of swath ships

100%
Michalski J. P.
Polish Maritime Research
|
2008
|
tom 15
|
nr 1
This paper contains formulation of a parametric method for evaluation of SWATH ship’s hull resistance. The method was elaborated on the basis of numerical calculation results obtained by using structural methods based on ship hydrodynamic theory and performed for sufficiently large series of body forms with systematically changing ship form parameters.Also, results of verifying investigations dealing with features of the method in question are presented by comparing the obtained resistance characteristics with those achieved by other authors as well as with ship model experimental test results. The obtained results of the verification indicate that the elaborated method can be useful in preliminary designingthe SWATH ships
12

A method for predicting propeller-hull interaction, applicable to preliminary design of inland waterways ships

100%
Michalski J. P.
Polish Maritime Research
|
2006
|
nr Special Issue S2
This paper presents a proposal of a parametric method for predicting the characteristics of wake fraction, w( x), and thrust deduction, t( x), of ship hull of the draught close to waterway depth. The method makes it possible to take into account an influence of low waterway depth in preliminary selecting propulsion system parameters of ships intended for operating in shallow waters, e.g. of inland waterways ships. The mathematical model of the problem was determined with taking into account the aspect of coding easiness of calculation algorithm to be applied to computer software useful in computer aided design. Application of the method was demonstrated with the use of the example characteristics of the passenger ship intended for operating in shallow waters on Berlin-Kaliningrad route, whose design was elaborated in the frame of the EU Eureka INCOWATRANS E!3065 project
13

Parametric method of preliminary prediction of the ship building costs

100%
Michalski J. P.
Polish Maritime Research
|
2004
|
nr Special Issue
Paper presents results of studies on a parametric method of predicting ship building costs −− useful in the preliminary design. Conception and theoretical basis of the method arepresented, devised are also approximation formulae for estimating the building costs of theship hull, ship equipment and the power plant with propulsion system. Factors of importan-ce for the ship building costs are identified and a computational algorithm formulated. Theuseful character of the method is illustrated by examples of building cost predictions forfour different ship types designed in the Eureka project E!2772, i.e.: SINE 202 universalcontainer carrier, SINE 203 oil product tanker, SINE 204 ro-ro ship and SINE 205 river-sea ship
14

A method for preliminary estimation of the length of midship body block to be inserted during ship’s conversion

100%
Michalski J. P.
Polish Maritime Research
|
2017
|
tom 24
|
nr 1
The paper presents a method for preliminary estimation of the length of the midship body block, which inserted in the original hull, increases the deadweight of the ship in line with a required quantity. The method may be useful for establishing the scope of conversion to better adjust the ship for transportation tasks. The problem is formulated by using a mathematical model so selected that its solution, under set of assumptions, is obtained in a closed analytical form. The presented method can be useful for application to pre-investment analysis of the ship conversion costs and functional profits
15

Parametric method of prediction of the ship operating costs

100%
Michalski J. P.
Polish Maritime Research
|
2004
|
nr Special Issue
Paper presents results of studies on a parametric method of predicting ship operatingcosts - useful in the preliminary ship design. Conception and theoretical basis of the method are presented, identified are also factors of significant importance for the ship opera-ting costs, taking into account changes in the value of money. Approximation formulae forestimating the operating cost components have been developed as well as a computationalalgorithm based on a minimum Required Freight Rate (RFR). The useful character of themethod is illustrated by examples of operating cost predictions for four different ship typesdesigned in the Eureka project E!2772, i.e.: SINE 202 universal container carrier, SINE 203 oil producttanker, SINE 204 ro-ro ship and SINE 205 river-sea ship
16

A parametric method for preliminary determination of underwater vehicles deadweight

100%
Michalski J. P.
Polish Maritime Research
|
2012
|
tom 19
|
nr 2
This paper describes a method useful for determination of load carrying capacity of underwater vehicle, elaborated on the basis of investigations of series of vehicles of systematically changed geometrical dimensions. By using the set of the series of vehicles their structural mass and displacement – at a given structural material and assumed maximum permissible submersion depth – were determined, and next – approximation formulae for deadweightof vehicles were obtained. Vehicle’s form may be consisted of one or a few cylindrical floats of circular cross-section, ended with caps. The floats are joined together with a space pipe frame. Acceptability of design solutions results from comparison of working stress values in float’s shell plating with permissible stresses as well as critical stresses. The presented method may be useful in the preliminary stage of designing the underwater vehicles - i.e. may serve for preliminary determination of a vehicledeadweight – at its given, or determined, geometrical dimensions, maximum permissible submersion depth, as well as a selected structural material
17

A design concept of ecological tourist-passenger ship intended for Berlin - Krolewiec (Kaliningrad) inland waterway service

51%
Kolowko W., Michalski J. P., Rosochowicz K.
Polish Maritime Research
|
2006
|
nr Special Issue S2
This paper presents a design concept of a novel passenger segment ship intended for navigating on Berlin- -Królewiec (Kaliningrad) inland waterway route, characteristic of application novel structural materials and engineering processes which make it possible to design structures in an innovative way and provide high operational merits for inland waterways ship. Conceptual, functional and technical assumptions for the designed ship as well as its service program was described. Exceptional features of the designed ship are : the general architectural concept which makes the ship free passing under small-clearance bridges and navigating in narrow and shallow waterways, possible, manufacturing technology of its hull structure made of „sandwich” panels as well as its combustion-electric engine (or combustion-hydraulic engine) propulsion system working on alternative ecological gas fuels
18

Incorporation of endogenous urea nitrogen into the amino acids of bacterial protein in the rumen of goats fed diets with various protein levels

51%
Michalski J. P., Kowalczyk J., Czauderna M., Litwin W.
Journal of Animal and Feed Sciences
|
2013
|
tom 22
|
nr 4
The aim of the study was to investigate the effect of different levels of protein in a diet on the incorporation of endogenous urea nitrogen (EUN) into individual amino acids (AA) of the ruminal bacteria of goats fed a low- (LP), medium- (MP), or high-protein diet (HP) in a 3 × 3 Latin square design. Three Alpine goats of about 35 kg body weight fitted with cannula into the rumen and catheter into the jugular vein were fed three isoenergetic diets containing 11% (LP), 13% (MP), or 16% (HP) crude protein in dry matter. The goats were infused for 6 days continuously with an 15N urea solution into the jugular vein. Ruminal bacteria were hydrolysed with 6M HCl. Next, butyl derivatives of free bacterial AA were obtained using HCl in butanol, then N-acylated using trifluoroacetic acid anhydride and analysed by gas chromatography using a mass-selective detector. The concentration of urea in plasma was 178, 356 and 667 mg · l–1 in goats from groups LP, MP and HP, respectively. 15N-excess during the infusion of labelled urea was significantly higher (P < 0.05) in the vast majority of AA of ruminal bacteria from goats fed the LP diet in comparison with goats fed the HP diet. Therefore, the level of protein in the diets affects the incorporation of EUN into bacterial AA. With the LP diet, EUN was incorporated mostly into glutamic acid, isoleucine and arginine, while in the case of the HP diet, into glutamic acid and arginine, as well as methionine. Regardless of the level of nitrogen in the diets, the incorporation of 15N into proline was very low. Irrespective of the dietary nitrogen level, EUN appears to be predominantly used for synthesis of glutamic acid in ruminal bacteria.
19

Effect of a protein level in the diet on fatty acid profile in goat milk

51%
Czauderna M., Kowalczyk J., Michalski J. P.
Journal of Animal and Feed Sciences
|
2010
|
tom 19
|
nr 2
211-217
The aim of the study was to evaluate the influence of feeding goats diets with different protein levels (11.4, 13.3 and 16.9%) and a small change of fatty acid contents on the concentrations of trans11C18:1 and conjugated linoleic acid (CLA) isomers in milk. The experimental design was 3 × 3 Latin Square. Each 22-day experimental period consisted of 14 days adaptation to the diets and 8 days for milk samples collection. Separation of methylated CLA isomers was achieved using GLC. Milk production was nearly the same when the low- and medium-protein diets were fed, while the high-protein diet resulted in a tendency to increase milk production. The concentrations of atherogenic (A-SFA), thrombogenic (T-SFA) and total saturated fatty acids (SFA) were similar in milk from goats fed the diets containing low- and medium-protein contents, whereas the diet containing the highest protein content resulted in an increase in the daily production of SFA and A-SFA in milk. The concentration and daily production of cis9trans11CLA, trans10cis12CLA, the sum of CLA isomers and usually trans11C18:1 and the sum of trans,transCLA isomers in milk increased as the dietary protein level increased. The higher dietary protein content resulted in the decrease in the concentration ratio of SFA and unsaturated fatty acids (UFA) (SFA/UFA) and tended to the increase in the capacity Δ9-desaturation.
20

The dietary level of selenite and selenized yeast influences the concentrations of selected fatty acids in the abdominal fat and brain of rats

51%
Czauderna M., Kowalczyk J., Krajewska K. A., Michalski J. P.
Journal of Animal and Feed Sciences
|
2010
|
tom 19
|
nr 1
113-129
The effects of supplementing diets with a mixture of conjugated linoleic acid (CLA) isomers (CLAmix) and/or selenium as Na2SeO3 (SeIV) or selenized yeast (SeY) on the growth performance of rats and on the contents of some fatty acids (FA) in their abdominal fat and brains were investigated. The study was performed on 80 female Wistar rats (Hsd Brl Han: WIST), 8 weeks of age with an initial body weight of 195.4±0.8 g. Each group numbered 8 rats. During the 7-day preliminary period the rats were fed a standard Labofeed H diet at a sub-maintenance level. Next, for 6 weeks the rats were fed ad libitum on the experimental diets supplemented with CLAmix, 0.2 ppm Se or 0.5 ppm Se as SeIV (LSeIV or HSeIV, respectively) and SeY (LSeY or HSeY, respectively). The rats were sacrificed at the end of the six-week experimental period. The diets enriched in HSeIV, LSeY, or HSeY increased the body weight gain (BWG) compared with the control rats, while the dietary CLAmix had a negligible effect on BWG in comparison with the control group. The addition of CLAmix to the diet enriched in Se, regardless of the level of extra Se and its chemical form, showed a negligible influence on the BWG in animals compared with rats fed the diet containing only LSeIV, HSeIV, LSeY or HSeY, respectively. Dietary LSeIV resulted in a decrease in the content of saturated fatty acids (SFA), atherogenic SFA (A-SFA), thrombogenic SFA (T-SFA), mono- (MUFA), poly- (PUFA) unsaturated fatty acids, PUFAn-3, PUFAn-6, c9C18:1, c9c12C18:2 (LA), c6c9c12C18:3 γ-LNA), c9c12c15C18:3 (α-LNA) and the sum of FA in the fat of rats. The diets enriched in CLAmix, HSeIV, LSeY or HSeY generally exhibited a smaller influence on the level of these FA in the fat compared with rats fed the diet with LSeIV. The diet with LSeIV had a negligible influence on the content of long-chain PUFAn-3 and n-6 (LPUFAn-3 and LPUFAn-6) in the fat compared with the control rats. The diet with LSeIV numerically or statistically increased the ratio of PUFA/SFA, MUFA/ SFA, UFA/SFA, and PUFA/FA in the fat compared with the control group. Other experimental diets resulted in inconsistent and negligible changes of these ratios in the fat compared with the control group. The diets with CLAmix or Se (as SeIV or SeY) reduced the content of C14:0, C16:0, C18:0, c9C18:1, LA, αLNA, c11c14c17C20:3, c8c11c14C20:3, c5c8c11c14C20:4, c7c10c13c16c19C22:5, c4c7c10c13c16 c19C22:6, SFA, A-SFA, T-SFA, MUFA, PUFAn-3, LPUFAn-3, PUFAn-6 and LPUFAn-6 in the brain compared with the control group. The diet enriched in CLAmix and Se (as LSeIV, HSeIV, LSeY or HSeY) decreased the content of these FA in the brain (the interactions: P<0.01). The ratio of PUFA/SFA, MUFA/SFA, UFA/FA and PUFA/FA was higher (P<0.01) in the brain of rats fed the diet with the one additive than in the control group. The diet enriched in CLAmix or Se (as SeIV or SeY) decreased Δ9-desaturase capacity in comparison with the control rats; interaction effects of CLAmix x Se (as HSeIV, LSeY or HSeY) were found (P<0.01). Feeding rats with the diet enriched in HSeIV or HSeY with or without CLAmix improved the nutritive value of the abdominal fat by increasing the content of LPUFAn-3, while the PUFAn-6/PUFAn-3 ratio decreased, particularly in the fat of rats fed the diet containing SeY. Finding that diets enriched in CLAmix and LSeY or HSeIV most effectively increased the content of CLA isomers in the abdominal fat and efficiently elevated body weight accretion and feed conversion efficiency in rats is valuable information for nutritionists carrying out research to improve the value of food derived from monogastric animals for human health.
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