Glossary

Update: Nov 8th, 2010

Jump to: A B C D E F G H I J K L M N O P Q R S T U V W X Z

A
AA Alternatives analysis (related to: EIR)
AB3034 California Assembly Bill 3034 (passed via prop 1A in Nov 2008) which authorizes the sale of $9.95 billion in GO bonds toward the construction of the California HSR network and limited capital improvements to legacy standard-speed rail services.
AC AC Transit (Alameda county)
AC Alternating current
ACE Altamont Commuter Express
Acela Express High speed train service, Amtrak (related to: NEC)
AD-# California assembly district designation
aerial Elevated road or rail alignment supported by concrete pillars for the purpose of grade separation (related to: viaduct)
AFAIAC As far as I am concerned
AFAIK As far as I know
AGV High speed train product family, Alstom
alignment Detailed (lateral and vertical) specification of where rails will run
Alstom Train and systems vendor, France
Amtrak National passenger rail operator, USA
Amtrak California California state passenger rail operator
AnsaldoBreda Train and subsystem vendor, Italy
arcing Undesirable plasma discharge that occurs whenever an active pantograph briefly breaks contact with the OCS, e.g. due to icicles on the wire
ARRA American Recovery and Reinvestment Act (H.R.1-110th)
ARTIC Anaheim Regional Transportation Intermodal Center
articulated carriage see MU
ASCE American Society of Civil Engineers
ASME American Society of Mechanical Engineers
at grade Road or rail alignment at the level of the natural terrain
ATC Automatic Train Control, Japan (related to: PTC)
ATO Automatic Train Operation (related to: PTC)
ATP Automatic Train Protection (related to: PTC)
AV Antelope Valley (Palmdale-Mojave)
AVE High speed train service, Spain
axle load The highest static load supported by any axle on a given vehicle or, the highest such load permitted on a particular (stretch of) track or road
B
baby bullet Caltrain brand name for a standard speed express service level
BAC Bay Area Council
BART Bay Area Rapid Transit (San Francisco Bay Area)
berm See embankment
bi-level Rolling stock featuring two levels of seating above one another
BNSF Burlington Northern Santa Fe railroad
BOD Board of Directors
bogie Assembly of two conventional wheelsets in a frame that can rotate about a vertical axis relative to the vehicle superstructure, required for negotiating relatively tight corners. Wheelsets may be powered.
Bombardier Vehicle and subsystems vendor, Canada (train division headquartered in Germany)
bore Circular tunnel constructed using a TBM. Typically contains one, sometimes two traffic lanes or rail tracks.
BRT Bus Rapid Transit
BTW By the way
BUR Burbank airport
C
CA4HSR Californians for High Speed Rail (advocacy group)
CA California
CA-# California road/freeway designation
CAF Train and subsystem vendor, Spain
cant Angle enclosed by tops of rails and the horizontal plane in a curve
CAHSR California High Speed Rail project
CALPIRG California Public Interest Research Group
Caltrain Regional passenger railroad, San Francisco peninsula
Caltrain corridor Railroad ROW owned by PCJPA. Supports Caltrain and UPRR traffic, selected as preferred alignment for HSR starter line
CARRD Californians Advocating Responsible Rail Design
catenary see OCS
CBOSS Communications-Based Overlay Signal System, Caltrain’s proprietary PTC R&D project
CC Capitol Corridor (Amtrak California route)
CC Contra Costa county
CCJPA Capitol Corridor Joint Powers Authority
CEMOF Caltrain’s Centralized Equipment Maintenance and Operations Facility in San Jose
CEQA California Environmental Quality Act
ceramic disk brake Secondary brake system on HSR trains, mounted on axles. Material resists fading.
certification Assertion by a planning agency that it has complied with NEPA and/or CEQA
CHSR See CAHSR
CHSRA California High Speed Rail Authority
CMA Alameda county transportation authority
CO2 Carbon dioxide
coasting Unpowered travel across the boundary between two electrical segments of the OCS. Breaks are needed to accommodate phase differences in the AC power provided by different generating plants, as well as for maintenance.
commuter rail Passenger rail service operating primarily or exclusively during weekday rush hour
consist Train assembled ad hoc from unpowered rail cars, typically drawn by (a) locomotive(s)
corridor (Pre-existing) major transportation artery plus land to either side
coupling Mechanical connection between two consecutive rail vehicles in a train. May include electrical power and train control connectors for fast assembly/disassembly of complete trains from individual multiple units.
CPUC California Public Utilities Commission, the state-level rail safety regulator
CRH-# High speed train model designation, China
CSS Context Sensitive Solutions, the PRP’s planning method
CTC Centralized Traffic Control (related to: dispatcher)
CTCS Chinese Train Control System (related to: PTC, ETCS)
cut-and-cover Method for constructing a tunnel from above as a trench with a lid
cut-and-fill Method for constructing a shallow trench in which the spoil is used to construct low berms to either side
CV Central Valley (Redding-Sacramento-Bakersfield)
D
DB National railway operator, Germany
dB Decibel, a logarithmic measure of relative signal strength (e.g. sound level)
dB(A) Decibel, weighted using the so-called A-curve to take into account the sensitivity of the human ear as a function of sound frequency
DC Washington, District of Columbia
DC Direct current
dead man’s switch Fail-safe mechanism that automatically engages the emergency brakes on a train unless the driver keeps it depressed
DEIR Draft EIR for public review (related to: CEQA)
dispatcher Operations controller authorized to manage train movements on a line or network
DMU Diesel-hydraulic multiple unit (see MU)
deep underpass Underpass in which the upper road or rail alignment is at grade (see underpass, at grade)
DEMU Diesel-electric multiple unit (see MU)
distributed power See distributed traction
distributed traction Propulsion concept featuring powered axles on multiple cars or locomotives, all controlled by a central computer (see MU)
DOT See USDOT
DTS Decline to state (independent voters in California)
DTX Downtown extension (tunnel in San Francisco)
Duplex Alstom’s bi-level TGV trainset product
DX Desert Express (Las Vegas-Victorville with potential connector to CHSR)
E
EB Eastbound
eBART Project to extend BART service east to Antioch
ED Eminent Domain
eddy current brake Supplemental brake system. Powerful electromagnet can be lowered to just above the top of rail to dissipate kinetic energy by heating the rail. Installed on ICE3 trains, can only be used at sufficiently high speeds.
EIR Environmental Impact Report (related to: CEQA)
EIS Environmental Impact Statement (related to: NEPA)
electrification Engineering project to add an OCS or third rail to a pre-existing rail corridor to enable the operation of electric trains
electro-pneumatic brake Tertiary fail-safe brake system on HSR trains. Latches preventing brake shoes from being pressed against the rims of the wheels are released using locally stored compressed air unless a control current keep the valve in the closed position. On-board batteries prevent accidental triggering during coasting or arcing events.
embankment Artificial earth mound with sloping sides, supporting an elevated road or rail alignment
emission Harmful chemical or noise generated by a given source, e.g. a train
EMU Electric multiple unit (see MU)
EPB Earth Pressure Balance, an efficient TBM variation for soil that is soft but not too wet
ERTMS European Rail Traffic Management System (related to: ETCS, GSM-R)
ETCS European Train Control System (related to: PTC)
ETR-# High speed train model designation, FS (Italy)
EU European Union
Eurostar High speed train service, UK/France
Eurostar High speed train service, Italy
express Train that stops only at major stations along a given route, if any (regardless of route length)
F
FAA Federal Aviation Authority
four-quadrant operation Characteristic of power converter capable of operating an electric machine in both motor and generator modes, in both rotation directions
FONSI Finding of No Significant Impact (related to: CEQA)
FRA Federal Railroad Administration (part of USDOT)
FS National railway operator, Italy
FSSF Fast-slow-slow-fast (related to: track order)
FTA Federal Transit Authority (part of USDOT)
FUD Fear, uncertainty and doubt
FWIW For what it’s worth
FY Fiscal Year
FYI For Your Information
G
GO 26-D General Order 26-D governing rail station platform heights in California (related to CPUC)
GO bonds General obligation bonds sold by the state of California, serviced out of the General Fund (i.e. general state tax revenue). Voters must authorize the sale by passing a proposition by simple majority before the state legislature can actually appropriate some or all of the bonds in the context of a balanced budget, which it must pass with a 2/3 supermajority.
grade separation Civil engineering structure with cross traffic lanes and/or tracks at different vertical elevations at an intersection
gradient Tangent of the angle enclosed by the slope of a rail alignment and the horizontal plane. Must be corrected upward if the alignment is also curved.
GSM-R Highly reliable terrestrial wireless signaling technology, Europe
H
HBF Hauptbahnhof (German for main/central train station)
headway Time difference for the front ends of two consecutive trains passing a fixed location
hikari Limited stop train, Japan (related to: shinkansen, limited)
Hitachi Train and subsystem vendor, Japan
HMF Heavy maintenance facility
HNTB A US infrastructure planning and construction company
HSIPR High Speed Intercity Rail Program, run by the FRA
HSR High Speed Rail (over 110mph in the US, over 200 km/h elsewhere)
HSRA See CHSRA
HST High Speed Train (related to: HSR)
H.R. # House Resolution designation (federal bill)
HRT Heavy rail transit (high-capacity public transportation systems such as subways, commuter/regional rail and intercity rail, typically 4 or 5 seats abreast, often partially or fully grade separated in built-up areas)
HRV Heavy rail vehicle (complete train, trainset, locomotive or individual passenger/freight car)
Hwy # Highway designation
I
I-# Interstate freeway designation
ICE# High speed train model designation, Germany
IE Inland Empire (roughly, Ontario-San Bernardino-Riverside)
immission Sum total of harmful chemicals or noise received at a particular location from all sources
IMHO In my humble opinion
IMO In my opinion
induction motor Highly robust electric machine, relies on frequency differential between stator and rotor three-phase currents to produce torque, therefore less efficient than synchronous motors. Typically deployed with a fixed ratio final drive gear box to reduce motor size and weight in powered bogies.
intercity rail Passenger rail service, typically with routes over 100 miles long
inverter Solid-state electrical machine that uses variable PWM to convert DC current into approximately sinusoidal three-phase AC current of any desired frequency in a defined range. Used for continuously variable motor speed control.
ITS Institute for Transportation Studies, University of California at Berkeley
J
jackknifing Conventional rail cars rotating to extreme angles relative to the tracks after a derailment, leading to capsizing and/or crushing of the superstructure. Greatly increases the risk of injuries and casualties in passenger rail contexts.
Javelin High speed train service, UK
Jacobs bogie Bogie located in-between short rail cars to reduce the risk of jackknifing in the event of a derailment (related to: Alstom)
JR Collection of regional railway operators, Japan
K
Kawasaki Train and subsystem vendor, Japan
km/h Kilometers per hour (1 km/h = ~0.6 mph)
kodama Local train, Japan (related to: shinkansen, local)
KTX-# High speed train model designation, South Korea
kV Kilovolt
L
LA Los Angeles
LACMTA Los Angeles County Metropolitan Transportation Authority (see also: MTA)
LA Metro Local transit operator in the city and county of Los Angeles
LAUS Los Angeles Union Station
LAWA Los Angeles World Airports
LAX Los Angeles airport (related to: LAWA)
Leq Equivalent sound level, computed by averaging over a defined time interval and expressed in dB(A). Used to objectively assess noise immissions in the context of environmental reviews, relative to pre-defined thresholds.
lid Concrete slab covering a (section of a) trench (related to: cut-and-cover)
limited Train that stops at most stations along a given route (regardless of route length)
LGV Ligne à grande vitesse (dedicated high speed line, France)
local train that stops at all stations along a given route (regardless of route length)
LOSSAN Los Angeles-Anaheim-San Diego rail corridor along I-5
LPA Locally preferred alternative
LRT Light rail transit (urban/suburban trams, max. speed 55mph, typically 3 seats abreast and room for standees, typically electrified via OCS, may operate in streetcar mode if LRVs are short enough)
LRV Light rail vehicle (typically articulated to negotiate tight corners)
M
MB Mission Bay (San Francisco neighborhood adjacent to Caltrain’s 4th & King terminus)
Metrolink Regional passenger rail operator, southern California
MP Menlo Park
mph Miles per hour (1 mph = ~1.6 km/h)
MTA Metropolitan Transportation Authority, New York City (see also LACMTA)
MTC Metropolitan Transportation Commission for the San Francisco Bay Area
MU multiple unit (articulated passenger rail vehicle, typically self-propelled and with driver cabs at either end)
Muni Municipal transportation authority and operator, San Francisco
N
NB Northbound
NCTD North Coast Transportation Division (San Diego county)
NEC Northeast Corridor (USA)
NEPA National Environmental Policy Act
NIMBY Not In My Back Yard
Nippon Sharyo Train and subsystem vendor, Japan
NJT New Jersey Transit (related to: NEC)
NorCal Northern California
nozomi Express train, Japan (related to: shinkansen, express)
NPV Net Present Value, relates past or future sums to present day by accounting for inflation
NRPC National Railroad Passenger Corporation (Amtrak’s legal parent organization)
NTV Private HSR operator, Italy
O
OAC Oakland Airport Connector (related to: BART)
objective metric Reliably repeatable physical measurement using an inanimate device
OAK Oakland airport
OC Orange county (southern California)
OCTA Orange County Transportation Authority
OCS Overhead catenary system
ONT Ontario airport (related to: LAWA)
OT Off topic
overpass Grade separation in which a road crosses another road or rail alignment via an aerial
P
PA Palo Alto
pantograph Articulated mechanism that provides the electrical connection between a (moving) train and the stationary grid (related to: OCS)
PAMPA Palo Alto, Menlo Park and Atherton
passenger rail Transportation of humans, pets and personal belongings on a train. Typically a for-fee service, often subsidized by taxpayers to reduce road congestion and/or improve air quality.
PB See PBQD
PBQD Parsons, Brinckerhoff, Quade and Douglas
PCC Peninsula Cities Coalition (San Francisco peninsula)
PCJPB Peninsula Counties Joint Powers Board (related to: Caltrain)
Pendolino High speed train product family with active tilt (related to: Alstom)
platform height Vertical distance between top of rail and the edge of the platform
PMD Palmdale airport (related to: LAWA)
PMSM Permanent Magnet Synchronous Motor, based on rare-earth ferromagnetic materials and control coils to manage the magnetization level. Some designs can be attached directly to HSR wheelsets, without a final drive gear box.
power Physical quantity representing energy flow per unit of time. May be expressed as e.g. force times speed, torque times radial velocity, voltage times current.
power converter Solid-state electrical machine combining a rectifier and an inverter
power diode Special large semiconductors designed to permit high currents to flow in one direction only. Require forced cooling. (related to: rectifier)
power transistor Special large semiconductors designed to switch high voltages and/or currents at various frequencies. Require forced cooling. (related to: inverter)
PPP Public-Private Partnership, a funding mechanism
PRIIA Passenger Rail Investment and Improvement Act (H.R.2095-110th)
PRP Peninsula Rail Program, planning body for the SF peninsula staffed jointly by Caltrain and CHSRA
prop (California) ballot proposition
PS Pacific Surfliner (Amtrak California route)
psychoacoustics Scientific study of how sounds are perceived by the human brain. Generally not used for environmental impact assessments as perception is based on subjective metrics.
PTC Positive Train Control, a combination of fixed and in-cab technology that can override driver control to ensure trains cannot exceed speed limits or run red lights (related to: PRIIA)
PUC See CPUC
PWG Policy Working Group, part of PRP
PWM Pulse Width Modulation, a method of controlling electrical current amplitude by using power transistors to interrupt the circuit for a defined fraction of a recurring very short interval
Q
Quantm Alignment optimization software, Trimble Corporation
R
railroad tie Wooden, concrete or steel element installed perpendicular to the rails to maintain the gauge and distribute the load as a train passes the location
rail yard Facility at which locomotives and/or rolling stock are stabled (parked), maintained and/or assembled into trains
RC Reverse condemnation (related to: ED)
rectifier Solid-state electrical machine that generates approximately DC current from AC current of any frequency. Used to supply inverters.
recuperative braking Primary brake mechanism for electric trains. Motors are operated in generator mode and the power fed back into the grid, provided it can immediately be used for the propulsion of some other train on the same electrical segment. Works best on busy lines.
RENFE National railway operator, Spain
retained fill embankment Embankment with straight sides contained within concrete walls to reduce lateral footprint
reverse split grade Grade separation in which a road crosses a moderately depressed road or rail alignment via a low overpass
RFF National rail grid operator, France
rheostat Secondary brake system on HSR trains. Essentially, giant force-cooled ohmic resistors, typically mounted on the roof of the vehicle. Only used if the OCS cannot accept (all of) the electricity produced by the electric motors in generator mode.
ROD Record of decision (endorsement of EIS by authorized federal agency)
ROTEM Train and subsystem vendor, South Korea
route Rough (lateral) specification of where rails will run, e.g. which cities will be connected
ROW Right of way
RR Railroad (generic)
RT Sacramento Regional Transit
ruling gradient The largest gradient on a given route (see gradient)
RWC Redwood City
S
S. # US senate bill designation
Sac Sacramento
SAN San Diego airport (Lindbergh Field)
SANDAG San Diego Association of Governments
San Diego trolley Local transit operator in the city and county of San Diego
Sapsan High speed train service, Russia (related to: Velaro)
SB California senate bill
SB San Bernardino
SB Southbound
SCAG Southern California Association of Governments
SCRRA Southern California Regional Railway Authority (related to: Metrolink)
SDMTS San Diego Metropolitan Transity System
SEPTA Southeastern Pennsylvania Transportation Authority (related to: NEC)
SF San Francisco
SFFS Slow-fast-fast-slow (related to: track order)
SFO San Francisco airport
SFTT See TTC
shinkansen Dedicated high speed line or train, Japan
Siemens Train and systems vendor, Germany
SJ San Jose
SJ San Joaquin (Amtrak California route)
SJ National railway operator, Sweden
SJC San Jose airport
sleeper See railroad tie
SMART Sonoma-Marin Train
SMCTA San Mateo County Transportation Authority
SMF Sacramento International Airport
SNCF National railway operator, France
SoCal Southern California
SP Southern Pacific (related to: UPRR)
split grade Grade separation in which a road crosses a moderately elevated road or rail alignment via a shallow underpass
S.R.-# State Route designation
stabling yard Parking lot for locomotives and/or rolling stock (related to: rail yard)
standard speed Trains and/or rail corridors operating at speeds below HSR levels (see HSR for thresholds)
starter line Initial route of a planned rail network. For California HSR, AB3034 defines this as “San Francisco Transbay Terminal to Los Angeles and Anaheim”.
streetcar mode Train running on track section embedded in a road lane. Only permitted for LRT in new construction in the US.
subjective metric Physical measurement based on the average assessment of a group of specially trained persons
subway Urban/suburban HRT, fully grade separated, typically even against other lines on the same network
subway tunnel See cut-and-cover
superelevation See cant
switching power supply Solid-state electrical device combining power semiconductors and a transformer operating at very high frequency. Slightly less efficient than a regular transformer but light and compact enough to permit passenger seating in all cars of an HSR trainset.
synchronous motor Highly efficient electric machine featuring stator and rotor three-phase currents of the exact same frequency
T
TALGO Train and equipment vendor, Spain
TBD To be determined
TBM Tunnel boring machine
TBT See TTC
tilt Mechanism for improving lateral acceleration comfort for passengers and hence, feasible speed, in relatively tight curves with insufficient physical cant. Passive for TALGO, otherwise active.
timetable Schedule detailing when and where trains are supposed to stop at stations along a given route
TGV Train à grande vitesse (high speed train in France, usually made by Alstom)
Thalys High speed train service, France/Belgium/Netherlands
third rail Electrical power supply installed at rail level. Cheaper and more compact than OCS, but grade separation required for pedestrian safety. Modest maximum voltage and hence power. Commonly used for subway systems.
THSR Taiwan High Speed Rail
TJPA Transbay Joint Powers Authority (San Francisco)
TOD Transit-oriented development
top of rail Reference elevation for equipment and platform design
track order Track assignment for fast HSR/express commuter and slower local commuter/freight services in a quad track context
trainset Aerodynamically optimized high speed multiple unit (see MU)
transformer Solid-state electrical device for converting between AC voltages
transit Local public transportation, typically subsidized by taxpayers and based on a combination of fixed-route buses, LRT and HRT with transfer stations
trench Excavated ditch containing a road or rail alignment. May feature sloping earthen sides or concrete side walls. May be covered with lids.
trolley See LRT
truck See bogie
TT See TTC
TTC Transbay Terminal Center (related to: TJPA)
TTT See TTC
tunnel Underground road or rail alignment, enclosed on all sides
tunnel boom Acoustic funnel effect at tunnel portals, increasing both volume and duration of environmental sound events
tunnel portal Structure terminating a tunnel where it emerges back above ground
TVM-430 PTC implementation, France
TWG Technical Working Group, part of PRP or CHSRA planning effort
U
underpass Grade separation in which a road crosses another road or rail alignment in a very short tunnel
UP See UPRR
UPRR Union Pacific Railroad
US-# Federally funded freeway designation (related to: I-#)
USDOT US Department of Transportation
V
Velaro High speed train product family, Siemens
VHSR Very High Speed Rail (over 300 km/h = 186 mph)
viaduct Elevated road or rail alignment supported by concrete pillars for the purpose of maintaining grade across a depression or valley in the topography (related to: aerial)
VTA Valley Transportation Authority for Santa Clara county
W
WB Westbound
WB World Bank
WETA Water Emergency Transportation Authority (SF Bay ferries)
wheelset Rigid assembly of two steel railroad wheels and an axle
wheelset Assembly of a U-shaped frame and two individual unpowered steel railroad wheels and axles (TALGO only)
WiFi Family of wireless local area network standards (IEEE 802.11)
WSX Warm Springs Extension (project to extend BART to Alameda county border in Fremont)
X
X-2000 High speed train service on heavy freight lines, Sweden
Y
yard See rail yard
YOE Year of Expenditure
Z
Zefiro High speed train product family, Bombardier

Jump to: A B C D E F G H I J K L M N O P Q R S T U V W X Z

Comments are closed.