Glossary of ECDIS related terms

INTERNATIONAL HYDROGRAPHIC ORGANIZATION GLOSSARY of ECDIS-RELATED TERMS 3rd Edition - December 1997 Special Publication No 52 Appendix Published by the International Hydrographic Bureau MONACO 400-II-1998 S-52 App INTERNATIONAL HYDROGRAPHIC ORGANIZATION GLOSSARY of ECDIS-RELATED TERMS 3rd Edition - December 1997 Special Publication No 52 Appendix Published by the International Hydrographic Bureau 4, Quai Antoine 1er B.P 445 - MC 98011 MONACO Cedex Principauté de Monaco Telex: 479 164 MC- INHORG Telefax: (377) 93 10 81 40 E-mail: info@ihb.mc Web: www.iho.shom.fr i Preface The purpose of this Glossary of ECDIS-related terms is to facilitate reading and interpreting the standards and specifications related to ECDIS issued by IMO and IHO, namely the ECDIS Performance Standards, the IHO Special Publications S-52 (including its Appendices) and S-57 This 3rd edition has been developed by the Glossary Working Group of the IHO Committee on Hydrographic Requirements for Information Systems (CHRIS) It has been completely revised based on the latest editions of the relevant ECDIS-related standards and specifications The reader should be aware that it is not intended to cover everything that has a bearing on ECDIS, and that many definitions only reflect a rather narrow meaning the terms have in conjunction with ECDIS The Glossary, therefore, should not be used as general reference for hydrographic, navigational or information technology terms Some of the relevant IHO specifications contain a glossary of terms on their own Only those definitions which have a wider use beyond the limits of a particular publication have been incorporated from these specific glossaries The "invention" of new definitions has been avoided as far as possible Use has been made instead of either general dictionaries such as the Hydrographic Dictionary (IHO Special Publication S-32), and Bowditch, or of other relevant documents References are provided in square brackets It should be noted that sometimes a definition taken from another source may be an excerpt from the original definition, or is slightly modified in order to better meet ECDIS terminology Where it was felt, however, that the special meaning of a term in conjunction with ECDIS requires a correspondingly specialized approach, new definitions were developed Advantage has been taken of guidelines provided in the "Short guide for writing definitions" published by the ISO TC211 Committee [ISO] In particular, an attempt has been made to separate the core of the definition from any additional explanations, examples etc through the addition of Notes All entries to the Glossary are given in lower case, except acronyms and proper names Cross references to other definitions in the Glossary are provided by italicizing the respective term Acronyms are integrated in the Glossary with cross references Some illustrations are annexed to the Glossary to show relationships between terms Any suggestions for improvement, corrections and extensions are welcome As the Working Group will be disbanded on publication of this edition, comments should be addressed to the Chairman of CHRIS through the International Hydrographic Bureau ii Page intentionally left blank accuracy The extent to which a measured or enumerated value agrees with the assumed or accepted value See precision [HD] aid to navigation Visual, acoustical or radio device external to a vessel designed to assist in the determination of a safe course or of a vessel's position, or to warn of dangers and obstructions [Bowditch] AIS See Automatic Identification System alarm An alarm or alarm system which announces by audible means, or audible and visual means, a condition requiring attention [PS] all other information Term used in the Performance Standards for ECDIS to describe information not belonging to the standard display Also sometimes called "on-demand information" (See Fig 3) application profile Data structure A defined subject of the S-57 [TS] Note: An application profile is defined for a specific purpose, such as the transfer of ENC data applier An entity controlling the application of the update information, e.g the mariner keying in update information, or the software inside ECDIS automatically processing the ENC update information [UG] area The 2-dimensional geometric primitive of an object that specifies location (See Fig 4) ARPA See Automatic Radar Plotting Aid attribute A characteristic of an object It is implemented by a defined attribute label/code, acronym, definition and applicable values In the data structure, the attribute is identified by its label/code The acronym is only used as a quick reference in related documents and in ENC Product Specification Attributes are either qualitative or quantitative [TS] Note: see Appendix A, IHO Object Catalogue attribute label/code A fixed length numeric label or a 2-byte unsigned integer code of an attribute as defined in Appendix A, IHO Object Catalogue [TS] attribute value See attribute label/code Automatic Identification System (AIS) An automatic communication and identification system intended to improve the safety of navigation by assisting in the efficient operation of vessel traffic services (VTS), ship reporting, ship-to-ship and ship-to-shore operations Note: A transponder is an example of an AIS AIS information may be displayed on an ECDIS automatic updating Either the semi-automatic or the fully automatic means of updating the ENC/SENC [UG] Automatic Radar Plotting Aid (ARPA) A system wherein radar targets are automatically acquired and tracked and collision situations computer assessed and warnings given azimuth The bearing of a geographical position, measured clockwise from north through 360 degrees [Bowditch] back-up arrangement Facilities enabling safe take-over of the ECDIS functions and measures facilitating means for safe navigation of the remaining part of the voyage in case of an ECDIS failure [PS] base data S-57 conforming data at the data producer's site that does not contain any update records Once this data is exchanged it becomes target data at the applier's site [TS] bearing (BRG) The direction from a reference station, usually from 000 degrees at the reference direction, clockwise through 360 degrees [Bowditch] block correction see chartlet cartographic object Feature object which contains information about the cartographic representation (including text of real world entities [TS] Note: The ENC Product Specification prohibits the use of cartographic objects in ENCs cautionary note Information calling special attention to some fact, usually a danger area shown on a chart, or other publication [HD] cell The basic unit for the distribution of ENC data covering a defined geographical area bounded by two meridians and two parallels, the content of which must not exceed Mbytes, and which is intended for a particular navigational purpose chain A sequence of one or more edges chain node Data structure in which the geometry is described in terms of edges, isolated nodes and connected nodes Edges and connected nodes are topologically linked Nodes are explicitly coded in the data structure (see Fig 5) [TS] Note: Spatial objects may be shared between feature objects Where spatial objects are shared, lines that cross are broken (into edges) at the intersection and a logical node is implied (ie nodes are not explicitly created, the geometry of the node remains part of the edge) Where spatial objects are not shared, lines may cross without being broken at the intersection Areas are defined by the sequence of edges that comprise their boundaries Lines are comprised of edges Point feature objects may only reference isolated nodes chart amendment patch see chartlet chart cell see cell chart information HO-information relevant to navigation contained in nautical charts (See Fig 2) chart datum A permanently established surface from which soundings or tide heights are referenced Short for chart sounding datum [HD] Note: A plane so low that the tide will not frequently fall below it [TR] chart A chart specifically designed to meet the requirements of marine navigation, showing depths of water, nature of bottom, elevations, configuration and characteristics of coast, dangers and aids to navigation [HD] Note: The carriage of up-to-date charts (plus certain other nautical publications) by vessels at sea is a mandatory requirement of SOLAS regulation V 20 The term nautical chart may be applied also to a specially compiled data base (e.g., the ENC), from which such a map can be displayed chart symbol A character, letter, line style, or similar graphic representation used on a chart to indicate some object, characteristic, etc [HD] chartwork All navigational procedures carried out on a chart, the elements and parameters of which are listed in Annex of the ECDIS Performance Standards CHRIS See Committee on Hydrographic Requirements for Information Systems C.I.E colour system Colour specification system established by the Commission Internationale de l'Eclairage, which permits a replicable description of any colour on any equipment; in contrast with other colour schemes, which are apparatus specific Colour is usually expressed in terms of the x and y chromaticity coordinates for the widely used chromaticity diagram, and a third dimension Y representing the luminance (perceived as brightness) of the light in candela per square metre (cd/m2) C.I.E colour coordinates can be transformed into RGB coordinates of a calibrated CRT clarifications section One of the mechanisms used to maintain S-57 See maintenance document clutter Excess information or noise data on a display reducing its readability Note: E.g., information overload on a chart, or confusing unwanted wave echoes on a radar display [HD] coastal warning A navigational warning promulgated by a national co-ordinator covering a coastal region or a portion thereof collection object A feature object which describes the relationship between other objects [TS] Note: An example of a collection object in S-57 is "aggregation" which is used, for example, to group together the different objects which together constitute a Traffic Separation Scheme colour calibration In order to reproduce the IHO colours for ECDIS, a colour calibration at the monitor must be performed to transform the CIE-specified colours for ECDIS into the colour coordinate system of the screen Calibration will ensure correct colour transfer at the time a display leaves the manufacturer's plant Methods of colour maintenance under operational use are under investigation Note: colour calibration is described in Appendix of IHO S-52 colour differentiation test diagrams Screen diagrams supplied in the Presentation Library for use by the mariner to check brightness and contrast settings and to find out whether the screen still has the capability of distinguishing the important colours colour fill Method of distinguishing different area features by filling areas with colour "Transparent" colour fill is used to allow information to show through the fill, e.g., soundings in a traffic separation zone colour tables Five colour tables are supplied in IHO S-52 Appendix 2, for selection by the mariner They are bright sun, day white-background, day black-background, dusk and night colours for ECDIS The colours specified by the IHO for ECDIS have been developed by Perception Institutes to give a clear display through the optimum colour contrast under all viewing conditions, and to minimise light emission on the darkened bridge at night Colours are used to aid in distinguishing between features Colours for ECDIS are specified in the CIE colour system Committee on ECDIS (COE) Committee of the IHO responsible for ECDIS matters until 1995 Now replaced by the Committee on Hydrographic Requirements for Information Systems (CHRIS) Committee on Exchange of Digital Data (CEDD) Committee of the IHO responsible for the Transfer Standard for Digital Hydrographic Data until 1995 Now replaced by the Committee on Hydrographic Requirements for Information Systems (CHRIS) Committee on Hydrographic Requirements for Information Systems (CHRIS) A Committee of the IHO tasked with promoting and coordinating the development of official digital products and services compilation In cartography, the selection, assembly, and graphic presentation of all relevant information required for the preparation of a new map/chart or a new edition thereof Such information may be derived from other maps/charts, aerial photographs, surveys, new data, and other sources compilation scale The scale at which the ENC data was compiled compilation update The correction information which has been issued since the last new edition of the ENC or since the last official update applied to the SENC, compiled into a single, comprehensive ENC update [UG] Note: Example: if a buoy has been relocated two or more times since the ENC Edition, only the last position, tailored to correct the position contained in the ENC Edition as issued, would be included Thus, the application of a compilation update is to correct the effective ENC Edition at the time of its distribution to a user, which could be some months or years after the Edition's initial distribution Compilation update is implemented in S-57 by means of a re-issue of an ENC conditional symbology procedure A decision-making procedure used to link an object-class to a symbol in cases where the symbol depends on circumstances (e.g whether a wreck is symbolised as an "isolated danger" depends on its relationship to the safety contour chosen by the mariner), or where symbolisation is complex (e.g light sectors) connected node A node referred to as a beginning and/or end node by one or more edge Connected nodes are defined only in the chain-node, planar graph and full topology data structures [TS] correction information See update information corrections See update information corrections section One of the mechanisms used to maintain S-57 See maintenance document corrupted data Any change in data introduced during, and as a result of, its transmission [UG] course The horizontal direction in which a vessel is intended to be steered, expressed as an angular distance from north clockwise through 360 degrees [Bowditch] course made good (CMG) The single resultant direction from a vessel's point of departure to its point of arrival at any given time [Bowditch] Note: Relates to each leg of the track course over ground (COG) The direction of a vessel's path actually followed, usually a somewhat irregular line [Bowditch] course up display The information is shown on the display (radar or ECDIS) with the direction of the vessel's course upward The display orientation is stabilized by means of the gyro until a new course direction is fed in Note: Course-up orientation avoids the disadvantages with the head-up display due to yawing or other changes in heading cumulative update The collection of all sequential correction information which has been issued since the last new edition of the ENC or since the last official update applied to the SENC [UG] cursor-pick The process of querying a point-symbol, line or area for further information from the data base which is not represented by the symbol data dictionary Conveys the meaning of entities and attributes, the relationship between entities and attributes and the relationship between attribute and value domains data model A conceptual specification of the sets of components and the relationships among the components pertaining to the specific phenomena defined by the model reality A data model is independent of specific systems or data structures The S-57 data model defines real world entities as a combination of descriptive and spatial characteristics These characteristics are defined in terms of feature objects and spatial objects and the relationship between them See Fig data quality indicator Indication of reliability and accuracy of surveys of a particular area provided through CATZOC attribute of the quality of data meta object in S-57 data set A logical grouping of S-57 data to which the S-57 data set descriptive records apply The data set descriptive records contain meta data The use of data set descriptive records is product specific and is, therefore, defined by a product specification If the data set descriptive records are repeated for each file in an exchange set, an instance of a file containing the data set descriptive records is called a data set If the data set descriptive records are encoded generally for the whole exchange set, the exchange set is referred to as a data set [TS] data structure A computer interpretable format used for storing, accessing, transferring and archiving data [ISO] datum (geodetic) A set of parameters specifying the reference surface or the reference coordinate system used for geodetic control in the calculation of coordinates of points on the earth Commonly datums are defined as horizontal and vertical datums separately For a local geodetic datum the reference surface is defined by five parameters: the latitude and longitude of an initial point, the azimuth of a line from this point, and the parameters of the reference spheroid Absolute datums specify the initial point of the reference ellipsoid to be (ideally) located at the earth's centre of mass For modern reference systems using datum information given by satellites additional parameters are defined, e.g gravity models [HD] datum (vertical) Any level surface (e.g sea mean sea level) taken as a surface of reference from which to reckon elevations [HD] Note: See also chart datum degradation The deterioration in the performance of a system below a specified minimum level Note: For example, the reduction in the information content of a display, a data base or other means of providing information below an acceptable or agreed level [IEC] Differential GLONASS (DGLONASS) see GLONASS 16 north-up display Information shown on the display (radar or ECDIS) with the north direction upward Note: The north-up display corresponds with the usual orientation of the nautical chart Notice to Mariners (NtM) A periodical notice issued by maritime administrations, or other competent authorities, regarding changes in aids to navigation, dangers to navigation, important new soundings, and, in general, all such information as affects nautical charts, sailing directions, light lists and other nautical publications [HD] NtM See Notice to Mariners object An identifiable set of information An object may have attributes and may be related to other objects Also see spatial object and feature object [TS] Object Catalogue The Object Catalogue is the feature schema for S-57 Its primary function is to provide a description of real world entities It contains a list of feature object classes (each relating to a real world entity), attributes and allowable attribute values object class A generic description of objects which have the same characteristics Note: Examples of object classes in S-57 are "buoy, cardinal" and "caution area" object description The definition of which object class a specific object belongs to object identifier The identification of a S-57 feature object The object identifier is the concatenation of the "Producing Agency", "Feature Identification Number" and "Feature Identification Subdivision" subfields Within the context of this Standard the object identifier is referred to as the "Long Name" [TS] Note: This provides a unique world-wide identifier for any object as specified in Para 3.1 of the ENC Product Specification official HO data See HO information official updates Updates provided in digital format by the Issuing Authority of the ENC being corrected, for integration with the ENC data in the SENC [UG] on-demand information The SENC information which is not part of the standard display See also: All other information See Fig 2, orientation The mode in which information on the ECDIS is being presented Typical modes include: north-up - as shown on a nautical chart, north is at the top of the display ship's head-up - based on the actual heading of the ship (e.g ship's gyrocompass) course-up display - based on the course or route being taken 17 other chart information See display category and Fig other navigational information Navigational information not contained in the SENC, that may be displayed by an ECDIS, such as radar information (See Fig 2) overscale To display the chart information at a display scale larger than the compilation scale Overscaling may arise from a deliberate overscaling by the mariner, or from automatic overscaling by ECDIS in compiling a display when the data included is of various navigational purposes Note: An indication is provided only for the partial overscale area of the display overscale area When the data displayed is from data of two different navigational purposes the chart display will, where drawn at the larger scale, include an overscale area of data from the smaller scale cell in order to complete the display This area should be identified by the "overscale pattern" of the Presentation Library Note: E.g., when sailing across the junction between a harbour chart and an approach chart own ship's safety contour The contour related to the own ship selected by the mariner from the contours provided for in the SENC, to be used by ECDIS to distinguish on the display between the safe and the unsafe water, and for generating anti-grounding alarms own ship's symbol A non-chart symbol used in ARPA and ECDIS to show the ship's position on the chart or ARPA display own-ship The term which identifies the vessel upon which an ECDIS is operating Performance Standards for ECDIS Minimum performance requirements for ECDIS, adopted by IMO 23 November 1995 as Assembly resolution and published as Annex to IMO Resolution A19/Res 817 (15 December 1995) pixel Contraction for "picture element" The smallest element resolvable by electronic raster devices such as scanner, display, and plotter [HD] planar graph A 2-dimensional data structure in which the geometry is described in terms of nodes and edges which are topologically linked A special case of a chain-node data structure in which edges must not cross Connected nodes are formed at all points where edges meet (See Fig 5) [TS] point The 0-dimensional geometric primitive of an object that specifies location (See Fig 4) polygon A non-selfintersecting, closed chain defining the boundary of an area [HD] 18 product specification A defined subset of the entire specification combined with rules, tailored to the intended usage of the transfer data See ENC product specification [TS] precision The degree of refinement of a value Not to be confused with accuracy [HD] presentation Cartographic design including drawing, use of symbols, use of colours, use of conventional practices, etc Presentation Library A set of mostly digital specifications, composed of symbol libraries, colour schemes, look-up tables and rules, linking every object class and attribute of the SENC to the appropriate presentation of the ECDIS display Published by IHO as Appendix of S-52 raster A regular array with information pertaining to each element (pixel) or group of elements [TS] raster data presentation Method of representing all, or part, of a chart digitally by a matrix-like scheme of pixels [HD] record A S-57 construct which is comprised of one or more tagged S-57 fields and identified by a key [TS] Regional ENC Coordinating Centre (RENC) In the Worldwide Electronic Navigational Chart Data Base (WEND) the IHO network of Hydrographic Offices, the regional node being responsible, as Issuing Authority, for official ENCs and official updates compiled from national ENC data relationship A logical link between two elements from the data model which may be spatial (e.g topological relationship) and/or non-spatial In general a relationship is implemented in the data structure as a pointer Note: The relationships permitted in ENC data are described in the ENC Product Specification [TS] relative motion display A display in which own ship remains stationary, while all other charted information and targets move relative to own ship's position See also true motion display RENC See Regional ENC Coordinating Centre resolution Capability of depicting detail, represented by the smallest distance apart at which two objects can be seen to be separate Depends on pixel size, i.e screen dimension divided by number of pixels route A sequence of waypoints and legs 19 route monitoring The operational navigational ECDIS function in which the chart information is displayed, under control of the positioning sensor input, according to the vessel's present position (either in true motion or relative motion display mode) route planning The pre-determination of course, speed, waypoints and radius in relation to the waters to be navigated, and in relation to other relevant information and conditions [NAV] Note: See also leg, route, voyage plan, waypoint S-52 IHO Special Publication 52, titled "Specifications for chart content and display aspects of ECDIS" Additional specifications and guidance are developed in the Appendices of S-52 S-57 IHO Special Publication 57 See IHO Transfer Standard for Digital Hydrographic Data safety contour See Own Ship's Safety Contour safety depth The depth defined by the mariner, e.g the ship's draft plus underkeel clearance, to be used by the ECDIS to emphasize soundings on the display equal to or less than this value Safetynet A service provided through INMARSAT's Enhanced Group Calls (EGC) system which will be used by Administrations for the promulgation of Maritime Safety Information, such as Navarea and storm warnings, shore-to-ship distress alerts and routine weather forecasts to the high seas and those coastal waters not served by Navtex IHO proposes to include promulgation of electronic chart corrections as well [UG] sailing directions A publication issued under the authority of a marine administration providing general coastal navigation information such as aids to navigation, harbour approaches and facilities, and other details necessary which it may not be feasible to show on the corresponding nautical charts Note: Sometimes referred to as Coastal Pilots or Coast Pilots scale The ratio between the linear dimensions of a chart, map, drawing, etc., and the actual dimensions represented [HD] scale bar A vertical bar scale of nautical mile divided into 1/10 ths., intended to convey an immediate sense of distance Replaced at display scales smaller than 1/80,000 by a 5-mile latitude scale screen The face of a CRT or other graphic device used to display information from a computer semi-automatic updating The application of corrections to ENC data in the SENC Updating in a fully integrated state, by hard media or telecommunications transfer in a manner which requires human intervention at the ECDIS interface 20 SENC See Systems Electronic Navigational Chart simplified symbols Symbols designed specifically for ECDIS, for fast draw and to give the maximum clarity under all conditions of viewing the CRT They are less complex than the equivalent paper chart symbols Note: For example, the simplified buoy and beacon symbols are solid, colour-filled symbols designed to show up better at night or in bright sun conditions than the true-to-shape paper chart symbols The mariner can choose paper chart or simplified symbol sets SOLAS International Convention for the Safety of Life at Sea developed by IMO The contracting governments undertake to promulgate all laws, decrees, orders and regulations and to take all other steps which may be necessary to give the present Convention full and complete effect, so as to ensure that, from the point of view of safety of life, a ship is fit for the service for which it is intended [SOLAS] sounding datum Same as chart datum (for the purposes of ECDIS) spaghetti data A data structure in which all lines and points are unrelated to each other (i.e no topological relationships exist in the data structure) [TS] Note: This data structure is not permitted for ENC spatial object An object which contains locational information about real world entities See Fig [TS] Note: for example, in S-57 the location of a buoy or the boundary of a caution area spatial record A spatial record is the implemented term used in the S-57 data structure for a spatial object (i.e a spatial object as defined in the data model is encoded as a spatial record in the data structure) There are three types of spatial records: vector, raster and matrix [TS] speed In general, the rate of motion or distance per unit of time When used in conjunction with ECDIS, speed could be either: [Bowditch] speed of advance (SOA) - speed intended to be made along the track speed over ground (SOG) - the speed along the path actually followed speed made good (SMG) - the speed along the course made good standard display See display category supplementary information Non-chart HO information, such as sailing directions, tide tables, light list (See Fig 2, 3) symbol see chart symbol System Electronic Navigational Chart (SENC) A data base resulting from the transformation of the ENC by ECDIS for appropriate use, updates to the ENC by appropriate means and other data added by the mariner It is this data base that is actually accessed by ECDIS for the display generation and other navigational functions, and is 21 equivalent to an up-to-date paper chart The SENC may also contain information from other sources (See Fig 1, 2, 3) [PS] target data Data on which an update operation is performed by the applier [TS] textual HO information Information presently contained in separate publications (e.g Sailing Directions) which may be incorporated in the ENC, and also textual information contained in explanatory attributes of specific objects time varying object An object which has one or more attributes, the value or values of which vary with time Note: An example of a time-varying object in S-57 is the geo object "Tide-Time Series" which gives the times and height of high and low water topology The set of properties of geometic forms (such as connectivity, neighbourhood) which is defined with the data model remaining invariant when subject to a continuous transformation Note: The level of topology chosen for the ENC allows for colour fill, activation of area warnings, e.g depth area warnings, cautionary areas The different levels of topology are described in the S57 Data Model track The intended path and past path of the ship When used in conjunction with ECDIS, additional terminology related to track can include: planned route (planned track): intended path past track: past path cross-track distance: distance right or left of intended path track keeping Sailing a ship in accordance with a pre-determined route, and in relation to the waters [NAV] Transfer Standard Maintenance and Application Development Working Group (TSMAD) A CHRIS working group which replaced the Database Working Group and the Transfer Standard Maintenance Working Group and which is responsible for the maintenance of S-57 and for the production of extensions to S-57 to satisfy new hydrographic requirements true distance Distance on the earth's surface, based on ellipsoid calculations true-motion display A display in which own ship and each target moves with its own true motion, while the position of all charted information remains fixed See also, relative motion display [ARPA] TSMWG A former CHRIS Working Group, now subsumed within the TSMAD Working Group, responsible for the maintenance of S-57 underscale The situation where the data displayed are not the largest scale navigational purpose data available for that area Note: An indication should be provided if data of a larger scale navigational purpose is available for the displayed area 22 update Either short for update information or, as a verb, applying the update mechanism See also official updates update information The data which are needed to update the target data automatically Update information comprises one or more update records [TS] update mechanism The defined sequence of update operations necessary to update the target data by applying the update information to the content of the target data so that no operator interaction is involved [TS] update record Generic term for feature or spatial records containing update instructions update set The collection of corrections to ENC data promulgated together by an issuing authority on a schedule basis [UG] Note: This is equivalent to the periodic set of Notice to Mariners issued for the correction of paper charts and nautical publications Use of the Object Catalogue Annex A of S-57 Appendix B.1 describing how to encode information relevant to a specific navigational purpose Must be used in conjunction with the ENC Product Specification Note: Use of the Object Catalogue is maintained by means of new editions, published as required by the Transfer Standard Maintenance and Applications Development Working Group The contents of a new edition not invalidate the contents of the previous edition vector Direct connection between two points, either given as two sets of coordinates (points), or by direction and distance from one given set of coordinates, or a point in a vector space defined by one set of coordinates relative to the origin of a coordinate system [HD] vector data presentation Method of representing individual chart features digitally by points, lines and polygons given through their coordinates and appropriate code(s) [HD] voyage data recorder A system that may be in the form of several separated but interconnected units, intended to maintain, in a secure and retrievable form, information concerning the position, movement, physical status, command and control of a vessel over a period leading up to, and following an incident Sometimes referred to as Black Box [VDR] Note: Not to be confused with the voyage data recording capability of an ECDIS (see voyage recording) voyage plan A defined series of waypoints, legs and routes voyage recording ECDIS capability to store and to reproduce certain minimum elements required to reconstruct the navigation and verify the official data base used during the previous 12 hours [PS] 23 warning An alarm or indicator water stabilization The reference system relative to the water based on course- and speed-through-water sensors Note: Used in conjunction with radar/ARPA See also ground stabilization waypoint In conjunction with route planning, a geographical location (e.g., latitude and longitude) indicating a significant event on a vessel's planned route (e.g., course alteration point, calling in point, etc.) WEND See Worldwide Electronic Navigational Chart Data Base window In computer applications, a rectangular subdivision of the screen showing information without affecting other parts of the screen; a method allowing to view different items of information (e.g different data sets or graphics) at the same time On graphical screens a window may be selected with the cursor and subsequently be enlarged (zoom) See also display World Geodetic System (WGS) A global geodetic reference system developed by the USA for satellite position fixing and recommended by IHO for hydrographic and cartographic use [HD] Worldwide Electronic Navigational Chart Data Base (WEND) A common, worldwide network of ENC datasets, based on IHO standards, designed specifically to meet the needs of international maritime traffic using ECDIS which conform to the IMO Performance Standards World-Wide Navigational Warning System (WWNWS) A service established for the purpose of coordinating the transmission of radio navigational warnings in geographical areas using coastal and satellite communication services [HD] zoom A method of enlarging (zoom in) or reducing (zoom out) graphics displayed on a screen 24 25 d isp la y e d in fo r m a t io n (2.1 ) p o sitio n a l in f o r m a tio n f r o m n a vig a tio n s e n s o r s (2.1 ) S E N C -in fo r m a t io n (2.1 ) radar in f o rm a ti o n E N C -i n fo r m a t io n o ffic i al u p d a te s (d i g it al ) (4.6 ) (4.5 ) c h a rt su p p l e m e n in fo rm a t io n ta ry in fo r(2.2 ) m at io n (2.2 ) L e gen d : a d d itio n a l n a vig a tio n -r e la te d in f o r m a tio n (2.1 ) m an u a l u p d a te s (6.1 ) o th e r n a v i g a tio n a l in f o rm a ti o n (6.1 ) (4.6 ) n a v ig a tio n a l d a ta a d d e d inform ation d a r im a g e A R P A e le m en ts in fo rm a t io n b y th e m ari - from other (6.3 1) a n d p a m e(6.3 1) n e r (2.3 ) sources (2.3) te rs (A pp ) In fo rm a tion ca teg o ry u se d in I M O P e rfo rm a nc e S ta nd a rd s (n u m b e rs in b ck e ts ref er to p ar ag p h n um b e rs o f IM O -P S ) i n fo r m a t io n In fo rm a tion ca teg o ry u se d in o th e r d o cu m e nts , su c h as I H O S - A A B B Info rm atio n A tran sferred digitally to info rm ation B Info rm atio n A tran sferred m an ually to info rm ation B F ig : R ela tio n sh ip b e tw e en in f o rm a tio n ca te g o r ie s u se d in I M O - P S an d o th er d o c u m en ts 26 S E N C - i n f o r m a t io n S t a n d a rd D is p la y A l l O th er I n fo r m a t io n ( ) ( ) o th e r s p e c i fi ed c h ar t i nf o r ( P S , A p p en d i x m at io n D isp la y B as e , N r 1 - ) ( A p p e n d i x , N r 2 - ) c h a r t i nf o r m ati o n d is p la ye d s u p p l em en tar y in f o rm a tio n in d iv id u all y on ( 2 ) d em an d (A ppend i x , N r -3 1 ) Legend: A B I ta lic s ( ) I n fo r m a t io n A fo r m s p a r t o f in f o r m a tio n B d a ta ad d ed b y th e m ar in er in f o rm at io n f r o m o th e r so urc es ( ) ( ) P r im e d is p la y c at e g o ri e s ac c o r d in g t o IM O -P S (n u m b e rs i n b c k e ts r e fe r to p a r a g p h n u m b e r s o f I M O - P S ) I n fo r m a t io n c a te g o r y u s e d f o r c o m p le m e n t in g t h e s c h e m a F i g : R ela ti o n s h ip b e tw een S E N C -d i s pl a y c a teg o ri es a n d c er ta in in fo r m a t io n ca teg o r ie s 27 OBJEC T iden tifie r attributes is lo ca ted b y FEATURE SPATIAL 1+ ag gr eg ate (d ep icts ) M ETA IHO OBJEC T GEO re late 2+ COLLECTIO N VECTO R RASTE R SPATIAL CAT A LOGU E NODE co ordinates (1 + b ou nd s ) EDG E co ordinates is of type a t least one one o r two ter m inate s ISOLATED NODE CO NNECTED NODE 1,2 ze ro or one ze ro or mo re to b e defined (1 + is a dja c en t to) 1+ re lated to : 1+ 1, M ATRIX (is co ntain ed in ) (g en er al S -5 op tio n) Fig 4: The data mod el of S-57, ed ition 3.0 (199 6) (1 + ) 28 Fig 5: Chain-node/planar graph data structure 29 References [Bowditch]: American Practical Navigator, Vol II Hydrographic/Topographic Center, 1981 edition [GNSS]: Maritime policy for a future Global Navigations Satellite System (GNSS) Draft Assembly resolution, NAV 42/23, Annex 12 International Maritime Organization, London, 1996 [HD]: Hydrographic Dictionary, Part I, Vol I (English) Special Publication S-32, fifth edition International Hydrographic Organization, Monaco, 1994 [IEC 1174]: Electronic chart display and information system - operational and performance requirements of testing and required test results Draft ver 10 (October 1996) [IMO]: IMO News 4/96 International Maritime Organization, London, 1996 [ISO]: WD 15046-4: Geographic information - Terminology - Second working draft: Guidelines for terminology and collection of terms from ISO/TC211 Geographic information/Geomatics ISO/TC211/WG (1997-04-09) ISO TC211 Secretariat, Norwegian Technology Standards Institution, Oslo [NAV]: Sub-Committee on Safety of Navigation: Report to the Maritime Safety Committee NAV 42/23/Add.1, Regulation 15(B), paragraph International Maritime Organization, London, 1996 [PS]: Performance Standards for Electronic Chart Display and Information Systems (ECDIS) International Maritime Organization, A19/Res 817, London, 15 December 1995 [SOLAS]: Article Ib of the International Convention for the Safety of Life at Sea International Maritime Organization, London, 1986 [TR]: IHO Technical Resolution A2.5 in: Resolutions of the International Hydrographic Organization IHO Publication M-3, Monaco, 1994 [TS]: IHO Transfer Standard for Digital Hydrographic Data, Edition 3.0 International Hydrographic Organization, Special Publication S-57, Monaco, November 1996 [UG]: Guidance on Updating the Electronic Chart, 3rd Edition 3.0 International Hydrographic Organization, Special Publication S-52, Appendix 1, Monaco, December 1996 [VDR]: Draft recommendation on Performance Standards for a shipborne voyage data recorder, Sub-Committee Safety of Navigation, NAV 42/WP.2 Annex International Maritime Organization, London, 1996 Defense Mapping Agency 30 Page intentionally 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A defined subset of the entire specification combined with rules, tailored to the intended usage of the transfer data See ENC product specification [TS] precision The degree of refinement of a value Not to be confused with accuracy [HD] presentation Cartographic design including drawing, use of symbols, use of colours, use of conventional practices, etc Presentation Library A set of mostly digital... specifications, composed of symbol libraries, colour schemes, look-up tables and rules, linking every object class and attribute of the SENC to the appropriate presentation of the ECDIS display Published by IHO as Appendix 2 of S-52 raster A regular array with information pertaining to each element (pixel) or group of elements [TS] raster data presentation Method of representing all, or part, of a chart digitally... national purposes other than WGS84 which is adopted for use with ECDIS 14 local updates A generic term to indicate all update information other than official updates, regardless of source; for application as a manual update only [UG] log file A record of updates, including time of application and identification parameters described in Appendix 1 of S-52 [IEC] look-up table A table giving symbology instructions... course-up display) HO-information Information content of the SENC originated by hydrographic offices It consists of the ENC content and updates to it (See Fig.2) identifier See object identifier 12 IEC See International Electrotechnical Commission IHO INT 1 Specification of symbols, abbreviations and terms to be used in the International Chart Series of IHO IHO Transfer Standard for Digital Hydrographic... layer A group of related information displayed as a whole leg A line connecting two waypoints line The one-dimensional geometric primitive of an object that specifies location (See Fig 4) List of Lights A publication tabulating navigational lights, with their locations, candle powers, characteristics, etc to assist in their identification, and details of any accompanying fog signal A list of lights may... digitally by a matrix-like scheme of pixels [HD] record A S-57 construct which is comprised of one or more tagged S-57 fields and identified by a key [TS] Regional ENC Coordinating Centre (RENC) In the Worldwide Electronic Navigational Chart Data Base (WEND) the IHO network of Hydrographic Offices, the regional node being responsible, as Issuing Authority, for official ENCs and official updates compiled from... textual information contained in explanatory attributes of specific objects time varying object An object which has one or more attributes, the value or values of which vary with time Note: An example of a time-varying object in S-57 is the geo object "Tide-Time Series" which gives the times and height of high and low water topology The set of properties of geometic forms (such as connectivity, neighbourhood)... subject to a continuous transformation Note: The level of topology chosen for the ENC allows for colour fill, activation of area warnings, e.g depth area warnings, cautionary areas The different levels of topology are described in the S57 Data Model track The intended path and past path of the ship When used in conjunction with ECDIS, additional terminology related to track can include: planned route (planned... Use of the Object Catalogue is maintained by means of new editions, published as required by the Transfer Standard Maintenance and Applications Development Working Group The contents of a new edition do not invalidate the contents of the previous edition vector Direct connection between two points, either given as two sets of coordinates (points), or by direction and distance from one given set of coordinates,... Identification Subdivision" subfields Within the context of this Standard the object identifier is referred to as the "Long Name" [TS] Note: This provides a unique world-wide identifier for any object as specified in Para 3.1 of the ENC Product Specification official HO data See HO information official updates Updates provided in digital format by the Issuing Authority of the ENC being corrected, for integration