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1
Content available remote Selected accuracy aspects of determination sea bottom shape of fairways
100%
Makar A.
Archives of Transport
|
2006
|
tom Vol. 18, iss. 1
37-47
EN
Specificity of hydrographic soundings, which are conducted for determination the shape of the sea bottom for creating paper charts, cells of electronic navigational charts and dredging, cause arising many errors inftuencing on the accuracy of these surveys. This issue is important from ensuring the safety of navigation point of view, especially in constrained sea areas: fairways to harbours, anchorages and into harbours. Selected reasons for arising errors in determination of the sea bottom shape in fairways to harbours with the conception of minimising them have been shown in this article.
PL
Specyfika prowadzenia pomiarów hydrograficznych - mających na celu wyznaczenie kształtu dna na potrzeby tworzenia map papierowych i komórek map elektronicznych oraz na potrzeby prac pogłębiarskich - powoduje powstawanie szeregu błędów wpływających na dokładność pomiarów. Jest to zagadnienie istotne z punktu widzenia zapewnienia bezpieczeństwa nawigacji, szczególnie na akwenach ograniczonych: torach podejściowych do portów, kotwicowiskach i w portach. W artykule przedstawiono wybrane przyczyny powstawania błędów wyznaczania kształtu dna na torach podejściowych do portów wraz z koncepcją metody ich minimalizacji.
2
Content available Modeling of vertical distribution of sound speed in water using rational Bézier courves
100%
Makar A.
Hydroacoustics
|
2011
|
tom Vol. 14
149-156
EN
Modeling of one variable and two variables functions can be used in hydroacoustics and hydrography i.e. for modeling the vertical distribution of the sound speed in water (one variable functions) or sea bottom (two variable functions). There are many mathematics methods of modeling one variable functions. In the paper modeling of the one variable function for the vertical distribution of the sound speed in water using rational Bézier functions have been shown.
3
Content available Modeling of sea bottom using uniform rectangular Bézier pieces
100%
Makar A.
Hydroacoustics
|
2011
|
tom Vol. 14
143-148
EN
In the article the essence of uniform rectangular Bézier pieces have been shown. These issues are essential during creation the digital terrain model DTM. For creation the bottom model bathymetric surveys of Motlawa River have been used. The visualization of the bottom using uniform rectangular Bézier pieces has been presented.
4
Content available Dteremnination of spatial orientation of sounding vessel using floating core fluxgate
100%
Makar A.
Reports on Geodesy
|
2009
|
tom z. 1/86
123-128
EN
Determination of spatial orientation of sounding vessel is an essential problem from determination of acoustic wave reflection points in geodesic bathymetric surveys radiated by an echosounder point of view. Pitching, rolling and yawing as a result of wind, wavy motion and vessel movement determine the outlet angle of acoustic wave, trajectory of acoustic ray as a result of refraction, location of reflection point and determined depth on the basis of the distance between the transducer and reflection point measured by the echosounder. In the paper possibilities analyse of floating core fluxgate's application for determination of spatial orientation of sounding vessel have been presented. Compensation of pitching and rolling have only been presented because of sensor limitation.
5
Content available The sea bottom surface described by Coons pieces
100%
Makar A.
Zeszyty Naukowe Akademii Morskiej w Szczecinie
|
2016
|
tom nr 45 (117)
187--190
EN
In this paper, a method of mathematical description of a surface, which can be used for modeling the sea bottom and detecting underwater objects using sonar (a side scan sonar or a front one) or a multibeam echosounder, is presented. The method is based on Coons plates and is described in four steps, which can be used for determination of the sea bottom for spatial presentation and volume calculation. A new sounding vessel and its equipment were used for the collection of geospatial data, and the results of a geospatial model of the sea bottom on the basis of the collected data are shown. The sea bottom is presented using Coons surfaces and a triangulated irregular network.
6
Content available remote Estimation of the time delay of hydroacoustic signals for passive location of underwater objects
100%
Makar A.
Archives of Acoustics
|
2004
|
tom Vol. 29, no. 3
435-445
EN
In this paper a method of time delay estimation of acoustic signals radiated in water has been shown. The source of these signals is a moving ship. The gradient adaptive method of minimizing the error has been used. An algorithm of estimation using this method and the results of estimation the real signals radiated by a moving ship have been presented.
7
Content available remote Influence of the vertical distribution of the sound speed on the accuracy of depth measurement
100%
Makar A.
Reports on Geodesy
|
2001
|
tom z. 5/60
31-34
8
Content available Method of determination of acoustic wave reflection points in geodesic bathymetric surveys
100%
Makar A.
Annual of Navigation
|
2008
|
tom No. 14
1-89
EN
The target of the study is development of method of precise determination of water region's co-ordinates for various applications. Selected factors, as dynamics of the sounding vessel and environmental factors are taken into consideration. In spite of possibility of application motion sensors available on the market (more expensive than professional single-beam echo-sounders), an alternative method of determining pitching and rolling has been developed - introduced in a model of precise determining of acoustic ray's reflection co-ordinates - for a ray characterized by non-linear trajectory. It is an alternative for accelerometers used in hydrography and magnetometers with floating cores available on the market. Main theses of the study may be presented as the following: - the vertical sound speed in water has an impact not only on accuracy of the depth measurement but also on trajectory of the acoustic ray, resulting in its non-linear propagation, - having positions of two points known (in their specific locations), there is a possibility of determining pitching and rolling with an accuracy comparable with performance of the motion sensors, - application of the elaborated methods for selected factors determining accuracy of the hydrographic surveys shall influence accuracy of created charts, safety of navigation and efficiency in searching under-water objects in a significant way.
9
Content available remote Metoda estymacji czasów opóźnień sygnałów hydroakustycznych
100%
Makar A.
Zeszyty Naukowe Akademii Marynarki Wojennej
|
2001
|
tom R. 42 nr 4 (148)
43-55
PL
Przedstawiono rozwiązanie układu do estymacji opóźnień wąskopasmowych. Układ ma zastosowanie w biernym systemie łożenia obiektu podwodnego na podstawie pomiarów . Wykorzystano algorytm estymacji metodą największego spadku adaptacyjnych. Przeprowadzono badania symulacyjne oraz wykorzystano rzeczywiste sygnały poruszającego się okrętu zarejestrowane na poligonie pomiarowym
EN
The paper presents a solution of an arrangement used to estimate time d signals. The arrangement can be used in a passive system to źon of an underwater object on the basis of hydroacoustic algorithm of estimation with the most drop method was used as źon methods. Simulation investigations were conducted and real signals produced a moving ship were recorded in the measurement test field.
10
Estymacja opóźnienia sygnałów akustycznych metoda korelacji ciągów pseudoprzypadkowych
100%
Makar A.
Prace Naukowe Instytutu Telekomunikacji i Akustyki Politechniki Wrocławskiej. Konferencje
|
2001
|
tom Vol. 83, nr 27
285-288
EN
In this paper time delay estimation with pseudoaccidental sequences correlation method has been shown. There has been used time delay estimation system with phase loop tracking the pseudoaccidental sequence, where input signals are binary acoustic signals radiated by a moving ship.
11
Content available Strefa działania jednosensorowego pasywnego systemu optonawigacyjnego
100%
Makar A.
Zeszyty Naukowe Akademii Marynarki Wojennej
|
2010
|
tom R. 51 nr 4 (183)
107-116
EN
Heat field emitted by moving object may be used to localize the object by means of applied thermo-vision cameras making a passive optonavigation system of appropriate configuration. Attempts of determining a zone of such a system operation have been made in this article — operation of the referred system is based on application of one thermo-vision camera making a one-sensor azimuth-stadiometric system. Factors having impact on extend of the zone operation and their influence on the zone’s size itself and on the system’s operation are presented here.
PL
Pole cieplne emitowane przez poruszający się obiekt może być wykorzystywane do jego lokalizowania za pomocą kamer termowizyjnych tworzących system optonawigacyjny o odpowiedniej konfiguracji. W artykule podjęto próby określenia strefy działania takiego systemu — działanie systemu jest oparte na zastosowaniu jednej kamery termowizyjnej tworzącej jednosensorowy system azymuto-stadiometryczny. Przedstawiono czynniki wywierające wpływ na zakres strefy działania oraz wielkość samej strefy i funkcjonowanie systemu.
12
Content available remote Modeling of sea bottom using NURBS functions
100%
Makar A.
Reports on Geodesy
|
2005
|
tom z. 1/72
17-24
EN
In this article the mathematical basis of the slines and non-uniform rational B-splines used for surface modeling, especially for modeling of the sea bottom, have been shown. For presentation of bathymetric survey`s results one of the Post of Gdansk`s basins have been used.
13
Content available Approximation of vertical distribution of the sound speed in water using basis Hermite's polynomial
100%
Makar A.
Hydroacoustics
|
2012
|
tom Vol. 15
131-136
14
Content available Application of non-uniform B-Splines of 2-nd order for description vertical distribution of sound speed in water
100%
Makar A.
Hydroacoustics
|
2009
|
tom Vol. 12
133-140
EN
Modeling of the vertical distribution of the sound speed in water is useful during determination of the depth on the basis of the acoustic method, modeling refraction phenomena and determination the trajectory of the acoustic wave. For modeling 1D functions (vertical distribution of the sound speed) and 2D (surface of the sea bottom for hydrography) uniform B-Splines was used. In this paper description of uniform B-Splines and description and application of non-uniform B-Splines have been presented.
15
Content available Results of hydrographic surveys of sea area - Southern Słupsk Bank
100%
Makar A.
Reports on Geodesy
|
2010
|
tom z. 1/88
67-71
EN
The Słupsk Bank, formerly knows as the Stolpe Bank (after the former German name Stolp of the now Polish city of Slupsk) is a bank situated 16 miles northward of Ustka, is about 24 miles long east and west and 10 miles broad. It has on the greater partof it general depths of 10 to 18 m, sand; the shoalest part is the northwestern, where there are several patches with from 8 to 9 m water, and at the western end, where there is a depth of 10 m. On the southeastern edge of the bank the water deepens suddenly to 29 and 33 m and on the other edges gradually. Because of long distance to the coast and large area, hydrographic surveys are carried out by large hydrographic vessels in 24H system. Results of hydrographic surveys of the part of Slupsk Bank have been presented.
16
Content available The concept of passive optonavigational system
100%
Makar A.
Reports on Geodesy
|
2010
|
tom z. 1/88
73-78
EN
Thermovision is known physical phenomenon based on emission of electromagnetic fields by each body with temperature above than absolute zero. This emission is called, for the sake of the wave, infrared emission and for the sake of its property - thermoemission. Intensity of thermoemission is proportional to the temperature of the body. So, during measurement of infrared emission of the body there is possible to indirect measure its temperature. Characteristic application of the thermovision can be usage of thermoemission radiated by moving object for its localization. In this paper the concept of passive navigational system working on the basis of thermovision cameras placed on the land are used for detection and tracking objects emitting infrared waves.
17
Content available Hydrographic surveys of Wisłoujście fortress area
100%
Makar A.
Reports on Geodesy
|
2010
|
tom z. 1/88
61-65
EN
In the close vicinity of the Westerplatte peninsula lies a unique fortification monument - the Wisłoujscie Fortress. The name Wisłoujście (the mouth of the Vistula) dates back to the time when the Vistula had its estuary north of the Wisłoujście Fortress. The site was an area of strategic importance as it gave control of ships moving into and out of Gdańsk. The Fortress is surrounded by shallow water. Hydrographic surveys are important because of navigation safety of small ships and yachts and they are difficult because of limited maneuverability of sounding vessel and limitations in positioning. Results of hydrographic surveys of Wisłoujście Fortress have been presented.
18
Content available Założenia do pozycjonowania modułu rozpoznania podwodnego
100%
Makar A.
TTS Technika Transportu Szynowego
|
2015
|
tom R. 22, nr 12
2731--2734
PL
W artykule omówione zostały serwisy precyzyjnych systemów pozycyjnych stosowanych w geodezji, które mogą być zastosowane w hydrografii w pomiarach dynamicznych oraz w pracach badawczych, takich jak wystawianie oraz podejmowanie systemów podwodnych. Takimi systemami mogą być systemy aktywne i pasywne, akustyczne, termiczne, hydrodynamiczne oraz ich kompilacje tworzące systemy zintegrowane. Takim zintegrowanym systemem jest prezentowany system rozpoznania podwodnego do wykrywania i śledzenia obiektów w toni wodnej na podstawie odebranych sygnałów przez wielosensorowy układ pomiarowy realizujący pomiary kilku pól fizycznych.
EN
In the paper services of precise positioning systems used in geodesy have been presented. These services can also be used in hydrography in dynamic surveys and research such as positioning of underwater objects/systems. These systems can be active and passive one, acoustic, thermal, hydrodynamic and their compilations creating integrated systems. Integrated system is presented module of underwater detection and recognizing objects on the basis of received signals by multisensor system measuring physical fields.
19
Content available Influence of SNR on determination of location of underwater object by means of acoustics method
100%
Makar A.
Hydroacoustics
|
2001
|
tom Vol. 4
157--160
EN
Localisation of underwater sources is possible by means of measurements of the delay between signals, which are radiated by the source. There are many time delay estimation methods, one of them is the gradient type adaptive algorithm. One of estimation parameters is convergence coefficient, which influences on speed of the estimation process. Selection of the optimal value of this coefficient guarantees achievement of the estimated value of time delay in the shortest time. The value of this coefficient depends on received signals to noise ratio. In this paper has been shown time delay estimation with gradient type adaptive algorithm and factors, which influence on the value oj convergence coefficient. There also has been shown influence of SNR on working of the time delay estimation, which can be used in the underwater source localisation system. For research have been used real acoustics signals radiated by a moving ship.
20
Content available Pozycjonowanie pław sygnalizacyjnych w zastosowaniach specjalnych
100%
Makar A.
Autobusy : technika, eksploatacja, systemy transportowe
|
2016
|
tom R. 17, nr 6
1024--1028
PL
W artykule przedstawiono problematykę wyznaczania położenia obiektów podwodnych stanowiących podwodną infrastrukturę nawigacyjną służącą do zabezpieczenia pozycjonowania obiektów poruszających się w toni wodnej oraz modułów rozpoznania podwodnego. Przyjęto założenie, że pozycjonowanie odbywa się na podstawie współrzędnych jednostki pływającej, a istotnym zagadnieniem jest wyznaczenie przesunięcia punktu odbicia fali akustycznej w wyniku występowania zjawiska refrakcji.
EN
In the paper the issues of determination of localisation of underwater objects as the underwater navigational infrastructure for positioning of underwater moving objects and underwater detection modules have been presented. There have been assumed, that positioning is realized on the basis of the position of the vessel and the essential issue is to determine the displacement of the reflection point of the acoustic wave as a result of refraction phenomenon.
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