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General Transit Feed Specification
GTFS, or the General Transit Feed Specification, defines a common data format for Public transport timetable, public transportation schedules and associated geographic information. GTFS contains only static or scheduled information about public transport services, and is sometimes known as GTFS Static or GTFS Schedule to distinguish it from the GTFS Realtime extension, which defines how information on the realtime status of services can be shared. History What was to become GTFS started out as a side project of Google employee Chris Harrelson in 2005, who "monkeyed around with ways to incorporate transit data into Google Maps when he heard from Tim and Bibiana McHugh, married IT managers at TriMet, the transit agency for Portland (OR), Portland, Oregon". McHugh is cited with being frustrated about finding transit directions in unfamiliar cities, while popular mapping services were already offering easy-to-use driving directions at the time. Bibiana and Tim McHugh eventually got ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journey Planner
A journey planner, trip planner, or route planner is a specialized search engine used to find an optimal means of travelling between two or more given locations, sometimes using more than one Mode of transport, transport mode. Searches may be optimized on different criteria, for example ''fastest'', ''shortest'', ''fewest changes'', ''cheapest''. They may be constrained, for example, to leave or arrive at a certain time, to avoid certain waypoints, etc. A single journey may use a sequence of several modes of transport, meaning the system may know about public transport services as well as transport networks for private transportation. Trip planning or journey planning is sometimes distinguished from ''route planning'', which is typically thought of as using private modes of transportation such as bicycle, cycling, Car, driving, or walking, normally using a single mode at a time. Trip or journey planning, in contrast, would make use of at least one public transport mode which ope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foreign Key
A foreign key is a set of attributes in a table that refers to the primary key of another table, linking these two tables. In the context of relational databases, a foreign key is subject to an inclusion dependency constraint that the tuples consisting of the foreign key attributes in one relation, R, must also exist in some other (not necessarily distinct) relation, S; furthermore that those attributes must also be a candidate key in S. In other words, a foreign key is a set of attributes that a candidate key. For example, a table called TEAM may have an attribute, MEMBER_NAME, which is a foreign key referencing a candidate key, PERSON_NAME, in the PERSON table. Since MEMBER_NAME is a foreign key, any value existing as the name of a member in TEAM must also exist as a person's name in the PERSON table; in other words, every member of a TEAM is also a PERSON. Summary The table containing the foreign key is called the child table, and the table containing the candidate ke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Key
In the relational model of databases, a primary key is a designated attribute (column) that can reliably identify and distinguish between each individual record in a table. The database creator can choose an existing unique attribute or combination of attributes from the table (a natural key) to act as its primary key, or create a new attribute containing a unique ID that exists solely for this purpose (a surrogate key). Examples of natural keys that could be suitable primary keys include data that is already by definition unique to all items in the table such as a national identification number attribute for person records, or the combination of a very precise timestamp attribute with a very precise location attribute for event records. More formally, a primary key is a specific choice of a minimal set of attributes that uniquely specify a tuple ( row) in a relation (table). A primary key is a choice of a candidate key (a minimal superkey); any other candidate key is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CSV File
Comma-separated values (CSV) is a text file format that uses commas to separate values, and newlines to separate records. A CSV file stores tabular data (numbers and text) in plain text, where each line of the file typically represents one data record. Each record consists of the same number of fields, and these are separated by commas in the CSV file. If the field delimiter itself may appear within a field, fields can be surrounded with quotation marks. The CSV file format is one type of delimiter-separated file format. Delimiters frequently used include the comma, tab, space, and semicolon. Delimiter-separated files are often given a ".csv" extension even when the field separator is not a comma. Many applications or libraries that consume or produce CSV files have options to specify an alternative delimiter. The lack of adherence to the CSV standard RFC 4180 necessitates the support for a variety of CSV formats in data input software. Despite this drawback, CSV remains wides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Association Of German Transport Companies
The Association of German Transport Companies is the umbrella organization of organizations of transit authorities and other public transport companies. The membership fluctuates in the range of about 600 transport companies. It is a member of the International Association of Public Transport. The current organization (VdV) was founded in 1991 with its headquarters in Cologne. The predecessor is the (VöV) (Association of ermanPublic Transport Companies) that was founded in 1949 in Stuttgart with main office in Essen until 1959 when it moved to Cologne. There is a predecessor for the VöV as well deriving from umbrella railway organizations in the early 19th century that were forming a subsidiary of (Association of German Tram and Light Railway Authorities) in 1895 in Munich. With a broadened scope of non-railway transportation it changed its name to (Association of German Transport Authorities) in 1928 with the main office in Berlin. With the Nazi Gleichschaltung its functi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmodel
Transmodel, also known as Reference Data Model For Public Transport (EN 12896), is a European Standard for modelling and exchanging public transport information. It provides a standard data model and specialised data structures to uniformly represent common public transport concepts, facilitating the use of data in a wide variety of public transport information systems, including for timetabling, fares, operational management, real-time data, and journey planning. As of 2021, the current version of Transmodel is 6.0. Scope Transmodel provides a comprehensive conceptual model for public transport information systems, covering multiple subdomains including transport network infrastructure and Geospatial topology, topology, schedules, Journey Planner, journey planning, fares, fare validation, real-time passenger information, and operational systems. Transmodel is an entity-relationship model in Unified Modeling Language (UML), accompanied by detailed descriptions of the concepts, el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UTF-8
UTF-8 is a character encoding standard used for electronic communication. Defined by the Unicode Standard, the name is derived from ''Unicode Transformation Format 8-bit''. Almost every webpage is transmitted as UTF-8. UTF-8 supports all 1,112,064 valid Unicode code points using a variable-width encoding of one to four one- byte (8-bit) code units. Code points with lower numerical values, which tend to occur more frequently, are encoded using fewer bytes. It was designed for backward compatibility with ASCII: the first 128 characters of Unicode, which correspond one-to-one with ASCII, are encoded using a single byte with the same binary value as ASCII, so that a UTF-8-encoded file using only those characters is identical to an ASCII file. Most software designed for any extended ASCII can read and write UTF-8, and this results in fewer internationalization issues than any alternative text encoding. UTF-8 is dominant for all countries/languages on the internet, with 99% global ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Text File
A text file (sometimes spelled textfile; an old alternative name is flat file) is a kind of computer file that is structured as a sequence of lines of electronic text. A text file exists stored as data within a computer file system. In operating systems such as CP/M, where the operating system does not keep track of the file size in bytes, the end of a text file is denoted by placing one or more special characters, known as an end-of-file (EOF) marker, as padding after the last line in a text file. In modern operating systems such as DOS, Microsoft Windows and Unix-like systems, text files do not contain any special EOF character, because file systems on those operating systems keep track of the file size in bytes. Some operating systems, such as Multics, Unix-like systems, CP/M, DOS, the classic Mac OS, and Windows, store text files as a sequence of bytes, with an end-of-line delimiter at the end of each line. Other operating systems, such as OpenVMS and OS/360 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mapzen
Mapzen, founded in 2013 and headquartered in New York City, was an open source mapping platform company focused on the core components of geo platforms, including search (geocoding), rendering ( vector tiles), navigation/routing, and data. Mapzen's components are used by OpenStreetMap, CartoDB, and Remix, amongst others. The components, hosted on GitHub, are written in JavaScript, Ruby, Java, and Python. Mapzen's CEO, Randy Meech, was previously SVP of engineering for MapQuest. Mapzen was supported by Samsung Research America and was known to have hired mapping specialists from Apple. Mapzen shut down operations in late January, 2018. On the 28th of January 2019 The Linux Foundation announced Mapzen would become a Linux Foundation Project. Projects Mapzen's hosted products were powered by open-source components, including: Pelias- a geocoder/search engine Tangram- a set of cross-platform 3D map rendering libraries Tilezen- vector map tiles based on OpenStreetMap data Va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accessibility (transport)
In Transportation planning, transport planning, accessibility refers to a measure of the ease of reaching (and interacting with) destinations or activities distributed in space, e.g. around a city or country. Accessibility is generally associated with a place (or places) of origin. A place with "high accessibility" is one from which many destinations can be reached or destinations can be reached with relative ease. "Low accessibility" implies that relatively few destinations can be reached for a given amount of time/effort/cost or that reaching destinations is more difficult or costly from that place. The concept can also be defined in the other direction, and we can speak of a place having accessibility ''from'' some set of surrounding places. For example, one could measure the accessibility of a store to customers as well as the accessibility of a potential customer to some set of stores. In time geography, accessibility has also been defined as "person based" rather than "pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
