COACH DIGNOSISE AND INFORMATION SYSTEM (CDIS)
IN SUPERVISION OF:-
SUBMITTED BY:-
ASHOK KUMAR
GAUTAM (CE)
PRABHAT KUMAR YADAV
CARRIAGE DIRECTORATE EC
DEPARTMENT RDSO
PSIT
LUCKNOW
KANPUR-208020
Abstract
Advanced high speed railroad system
requires absolute improvement of the reliability and safety of both the train
and passengers and increase in cost for system maintenance has been emerged as
another challenge. Thus it’s necessary to develop the technologies that will
satisfy the needs in two different aspects, dubbed as reliability & safety
and maintenance cost. To that end, development of intelligent railroad system
including rolling stock is more than important. Intellectualization of railroad
system is based on development of constant real-time detection technology which
requires Information Technology-integrated intelligent monitoring system. In
general, monitoring system is needed for constant monitoring which enables to
detect abnormal symptom of the system and take preventive measures or counter
measures before emergency situation. And to maintain such a constant
monitoring, it’s necessary to identify the symptom by analyzing the information
using the sensor which functions to convert the physical symptom into
electrical signal. However, existing railroad monitoring system usually adopts
wire sensor and the need for using monitoring system with wireless sensor that
enables to monitor the parts of the bogie or driving system or the system
inaccessible in the vehicle has been on the rise. Thus, this study was
researched the existing railroad monitoring system and, for using monitoring
system with wireless sensor, this study also was intended to identify the
applicability of energy harvesting technologies which is regarded the new and
renewable energy for monitoring the intelligent railroad system.
About RDSO
The Research
Design and Standards Organization (RDSO)
is an ISO 9001 research and development organization under the Ministry of
Railways of India, which functions as a
technical adviser and consultant to the Railway Board, the Zonal Railways, the Railway Production Units, RITES and IRCON International in respect of design and standardization of railway
equipment and problems related to railway construction, operation and
maintenance.
The RDSO is headed by a Director General who ranks
with a General Manager of a Zonal Railway. The Director General is assisted by
an Additional Director General and 23 Sr. Executive Directors and Executive
Directors, who are in charge of the 27 directorates: Bridges and Structures,
the Centre for Advanced Maintenance Technology (AMTECH), Carriage, Geotechnical
Engineering, Testing, Track Design, Medical, EMU & Power Supply, Engine
Development, Finance & Accounts, Telecommunication, Quality Assurance,
Personnel, Works, Psycho-Technical, Research, Signal, Wagon Design, Electric
Locomotive, Stores, Track Machines & Monitoring, Traction Installation,
Energy Management, Traffic, Metallurgical & Chemical, Motive Power and
Library & Publications. All the directorates except Defense Research are
located in Lucknow.
Introduction
The
LED DESTINATION DISPLAY BOARD WITH COACH DIAGNOSIS AND INFORMATION SYSTEM for monitoring of important parameter using
various sensors and processing technologies being used worldwide for railway
application and integrated LED destination board for providing important
information like train number, train
name, destination and starting station along with direction of
journey and coach
commercial abbreviation to
the passengers. This system uses quad
band GSM/GPRS or HSDPA/HSUPA modem for wireless internet connectivity to
the base station for remote accessibility and monitoring of important
parameters. The system is also equipped with GPS technology
for tracking / keeping record of the fault
locations of the coach and calculating kilometer run by the coach on per day /
month /year basis. This specification covers
the general, functional design requirements of such system
for
Indian Railway coaches.
This specification requires
the reference to the following specifications:
Specification
|
Description
|
RDSO/SPN/144
|
The Safety
and reliability
requirement
of electronic
signaling equipment.
|
IS: 9000
|
Basic environmental
testing procedures for electronic
and electrical items.
|
IEC: 60571
|
Electronic equipment
used on railway vehicles
|
IS: 60947-1
|
IP65 protection
|
Description
LED
DESTINATION DISPLAY BOARD WITH COACH DIAGNOSIS AND INFORMATION SYSTEM means "complete
system including all related equipments,
such as, CPU,
GSM/3G modem, GPS system, various sensors, LED display units for outside the coach,
IP65 Mechanical Casings (Frame), other
control units, suitable power
supply
unit and all associated accessories,
wires, fittings etc.
Each Coach
shall be equipped with following
separate units along with required connectors
and
wiring for communication & power
supply
as per wiring scheme.
a)
Main Processing Unit : one
unit per coach
Description of Main Processing
Unit shall be as per clause no. 19.1 of Part –II of this specification.
b)
Coach diagnosis and processing module (Optional ) : one unit per
coach
Description of Coach Diagnosis and processing
module shall be as per clause no. 19.2
of Part –II of this specification.
c)
Slave
Destination Board
Display
system: Two units per coach
Description of Slave Destination
Board Display system shall be as per clause no. 19.3 of Part –II of
this specification.
d)
Boxed enclosure
Power Supply unit : one unit
per coach
Description of Boxed enclosure Power Supply unit shall be as per clause no.
19.4 of Part –II of this specification.
e)
Cable junction box: one unit per coach
Cable junction box for all the
signals or power supply wires coming to CDIS unit or Main processing unit shall
be suitably labeled, numbered for easy identification and maintainability.
All the units Except Slave destination board may be
mounted in a standard 19” rack mountable enclosure unit and this integrated
unit shall be mounted at suitable location in the coach power panel or any
other suitable place.
At least 2 USB interface of Main Processing unit , LCD
touch screen, SIM slots for GSM / 3G modem,
on/off switch, power indicator shall be provided in front side of the
rack for easy accessibility.
f)
Base Monitoring Unit Two units at each Depot
g) Centralised Web Server
:
For hosting of online services for user
and supplier and hosting of required database of all the train routes, rake
formations of trains a web server ( server availability 99.9 % uptime round the
clock ) shall be hired by Indian Railway to serve the entire fleet of coaches
as well as prospectus users (Indian railway and system supplier users) of the
system.
The
scope of
the
supply includes acceptance testing, installation
and commissioning on the coaches, On-Site Replacement Warranty for one year and
commitment to undertake Comprehensive Annual Maintenance Contract after
warranty period.Scope of supply includes PC software for preparation of train
routes, uploading and downloading of route data and other information.The purchaser
can purchase any or all of the above sub systems based
on their requirements.
Functional and Design
Requirement
Ambient conditions:
The display unit
shall perform satisfactorily under the following climatic conditions
:i) Ambient
temperature :
-5oC to 55oC
ii)
Max. Sunlight temperature :
700C
ii) Altitude :
Sea level to 2500 m
iv) Relative
humidity : 40% to 98%
v) The
rainfall is fairly heavy.
Power Supply Availability
110V AC or DC supply
is available from coach circuits. This Supply varies from 70V DC to 150V DC
with 2% ripple.
Main Proccesing
Unit (MPU)
Main
processing unit shall consists of
built-in GSM/3G modem, GPS receiver, 7 to10 inch capacitive touch screen
interface along with suitable system software (Windows 6 or Windows 7
embedded), processing memory 1 GB
minimum and storage memory 32 GB on board. The system shall also have various
serial interface modules like USB,
RS485, RS232, the system shall also have wireless LAN / WAN module, IP65 protected mechanical enclosure unit with
provision of external antenna for GSM modem and GPS receiver.
The Main Processing unit shall support the
CDIS (Coach Diagnostic and Information System) whose role shall be to collate
information from the various devices fitted in the coach like Water Level
measurement system, hot bearing monitoring system, Temperature Level Monitoring
system etc. All such devices will be connected to Main Processing Unit over the
available communication channels like full duplex RS485 at 57600 bps baud rate,
WLAN / Ethernet network. Data-interchange between CDIS and the various devices
shall follow the industry standard protocol. Such information collated by the
CDIS shall be forwarded using the GSM modem / WLAN network of the Main
Processing Unit to a central server through Socket Programming. In case the
network is not available such data shall be queued in Main Processing Unit and
forwarded on availability of GSM connectivity. Up to 32 devices can be
connected to the MPU each being allocated a memory cache of 100KB in the MPU
for such store and forward functionality.
The MPU shall be capable of communicating
with at least 2 display panels connected outside the coach over half duplex
RS485 interface. It shall be possible to add more displays in future.
Base Monitoring Unit
Base
Monitoring Unit (BMU) is a standard workstation Personal Computer, which shall
work on latest windows® software. The BMU shall be connected to GSM/3G data
Modem, and also with wired broad band internet with fixed IP address for the
connectivity with the web server.
Display Units
For Outside Coach
The
LED destination display unit shall be wall mounted with 1.6 mm thickness of
robust MS casing to IS:2062 grade Fe410WC of 1220mm X 220mm X 75mm size (with 5
mm oval amber colour Diffused LED display of 16x128 matrix) and 8 mm pitch.
Maximum allowed thickness of the enclosure unit is 75 mm, it may be in the range
of 50mm to 75 mm.
The
Display unit shall be used to display the following information:
1)The Train No.,
Coach commercial abbreviation in left right corner as shown in figure below in
fixed mode
1)
Train
Name -
[train name]
2)
Destination
of the train - [source
station] to [destination station]
3)
Train
route (via) -
Via [list of important station in route]
4)
Welcome
Message -
Indian Railways welcomes you
DESCRIPTION OF EQUIPMENTS
Each Coach
shall be equipped with following
separate units along with required connectors
and
wiring for communication & power
supply.
Main Processing Unit : - one unit per coach
Slave
Destination Board
Display
System: - Two units
per coach
Boxed
enclosure Power Supply unit : - one unit per coach
Base Monitoring Unit - Two units at each Depot
DATA
BASE
System
will have capability to generate any new Train No database and to store 100
train routes up & down data. However this data shall be provided by
coaching depot, as per their requirement in the following format in Hindi,
English and regional languages
Route No.
|
Train No.
|
Train Name
|
Starting Station Regional Language
|
Destination Station Regional Language
|
VIA (List of important station)
|
Ø This is the
area for which the strategies have been
developed .But there is need to explore the CDIS system .This area covers
sensing the coach status and simultaneously
reporting to main processing unit for further updation.
Main
Uncovered Scenarios
Main
uncovered scenarios are sensing the :
1.
Bearing temperature
2.
Air Pressure in air suspention tank
3.
Water level in water tank
4.
Vibration in wheels
These
scenarios will be sensed and information status will be send for further
updation.
1,Bearing Health Monitering:
Problem:
When train moves
then the bearing temperature get
increases due to rotation.Therefore the axel temperature gets increases because
of which the wheel temperature gets increases as a results wheel can get
deformed .
Fig 2 Subsequent
analysis of bearings show correct wheel and correct fault predicted
Vibration Analysis Technique
Four Stages of Bearing Failure
Stage 1. Earliest detectable indication of bearing failure using vibration analysis. Signals appear in the ultrasonic frequency bands around 250 KHz to 350 KHz. At this point, there is approximately 10 to 20 percent remaining bearing life.
Stage
2. Bearing failure begins to "ring" at its
natural frequency, (500 to 2,000 Hz) signal appears at the first harmonic
bearing frequency. Five to 10 percent remaining bearing life.
Stage
3. Bearing failure harmonics of the fundamental frequency
are now apparent. Defects in the inner and outer race are now apparent and
visible on vibration analysis of the noise signal. Temperature increase is now
apparent. One to five percent of remaining bearing life.
Stage 4. Bearing
failure is indicated by high vibration. The fundamental and harmonics begin to
actually decrease, random ultrasonic noise greatly increases, temperatures
increase quickly. Remaining life one hour to one percent.
Figure : The
acceleration sensor on the axle box
Temperature Analysise Technique:
The methodology involves the
following:
·
Temperature
sensors are attached in close proximity to all the bearings on a common shaft
or axle.
·
The sensors apply
input to a sensing unit that is self-contained and has wireless technology for
communication with warning devices.
·
The temperature
data of each unit is analyzed and compared electronically.
·
If any bearing
temperature varies more that 15°C, an alarm is transmitted and an LED indicator
will light.
·
The system is
self-powered by a small power supply which is actuated by the movement of the
equipment.
·
There is a
maximum allowable temperature in case all bearings are out of normal operating
range.
Acoustic Wave Senser for Monitoring of Bearing Temperature
Wärtsilä
has recently developed such technology, and an innovative wireless
temperature-sensing device is currently being promoted and installed by the
company. The operating principle of this system is to directly measure the
temperature of the connecting rod big end bearing using a temperature sensor
fitted as close as possible (within a few mm) to the bearing surface.
This temperature monitoring system is based on patented, Surface
Acoustic Wave (SAW) radar technology, which has been proven to be the most
reliable technology for real-time wireless temperature monitoring. The Signal
Processing Unit (SPU) generates a radio wave pulse, which is picked up by the
stationary antenna. This
then converts the radio wave into an acoustic wave, and sends it to the rotating
sensor. This acoustic wave propagates along the surface of a SAW chip fitted
with multiple reflectors, thus permitting the sensor to reflect a pulse train;
the time delay between echoes depends on the temperature of the SAW chip.
Fig: acoustic
wave senser
Fig: A general GUI representation of bearing health
Fig: a windows based
GUI representation on screen for bearing health
Conclusion:
We can implement any of the technique either
temperature measurement or vibration measurement.
Wheel
Temperature Monitering
When in trains breaks
are applied then some times , breaks get
stick to the wheels and due to which the temperature of the wheels get increases and sometimes
wheels get red hot at about 600 degree centigrade which is very hazardeous. Hence
there is need to proper monitor the wheel condition.
For monitoring wheel
condition ,we require a sensor which is mounted on coachat at a proper place so that it can measure temperature without being
damaged.There is technology using infrared sensor shown in fig:
Air
Pressure in Suspension Tank
Almost
all railway vehicles use bogies (trucks in US parlance) to carry and guide the
body along the track. Bogie suspension design is a complex and difficult
science which has evolved over many years.
The pressure in air suspension tanks have to be
monitored so that if excess air collect in tanks then air pressure will increase and air suspension tank can
burst out, and if correctly monitored then the bursting of air suspension tanks
can be checked out.
There are various types of pressure sensor .
i.
Deflection type
ii.
Strain gauge type
iii.
Piezoelectric type
1 .Deflection Type
Pressure Sensor:
This sensor uses an
elastic material to convert pressure to displacement e.g. stainless steel,
brass. The displacement will be proportionate to the value of pressure
exerted. Suitable to be used in an
automatic control system. The main element used is in the shape of Bourdon
tube, bellow or diaphragm. The secondary element is the element that will
convert the displacement to electrical signals where the displacement can be
detected through resistivity change, inductance or capacitance.
Fig :Resistive
type pressure sensor
2. Strain Gauge type Sensor:
Strain gauge is a type of resistive
transduction. Pressure measurement is obtained from displacement of elastic
element. Pressure is measured through force that is exerted on the diaphragm
where the force will be detected by the strain gauge and resistance change will
be produced. Wheatstone Bridge circuit is used to detect the change in pressure
and an amplifier is used to amplify the small output signals.
3.
Pizoelectric type Sensor:
This sensor consists of a piezoelectric
crystal (made from quartz) which functions as a force-sensitive voltage source
where the piezoelectric will be in between two plates. Pressure exerted on the
crystal surface is proportionate to the voltage produced by the crystal. This
sensor does not require any voltage supply. This sensor is suitable for fast
changing pressure measurement.
Requirement:
We
need a sensor which can measure the air pressure in air suspension tank
continuously and report to the master unit wirelessly, as bogie will be always
moving and operated in jerks so wires can damage and signals can not be send.
Conclusion:
Therefore
,we will have to discard piezoelectric sensors and strain gauge sensor and have
to prefer the deflection type sensors.
It will suit our application as both of the two sensor need direct pressure on
there surface to give output , whereas deflection type sensor work using spring which can be easily
operated by air .
Water Level
Sensor
In trains ,water level of tanks which provide water in
toilets of bogies is to be measured. When
the tank get empty it should be filled , but sometimes it get not noticed by
workers .Therefore passengers have to face problem hence, proper monitoring of
water level of tank should be done so as to check the problem.
There are various type of water level sensor :
Ultrasonic Level sensor:
Ultrasonic level sensors are used for
non-contact level sensing of highly viscous liquids,as well as bulk solids.
They are also widely used in water treatment applications for pump control and
open channel flow measurement. The sensors emit high frequency (20 kHz to
200 kHz) acoustic waves that are reflected back to and detected by the
emitting transducer.
The
Electronic Approach :
Fluid levels can also be measured using electronic techniques. These include resistive, capacitive, optical, sonic and gravity.
Fluid levels can also be measured using electronic techniques. These include resistive, capacitive, optical, sonic and gravity.
Resistive
Level Sensors
Resistive is the
simplest technique and is reliable when using a consistent liquid with a
relatively small variation of resistance. With this approach, electronics can
more easily deal with the replication of individual sensors to provide level
information and limits, as
A capacitive type of sensor can be an array of sensors that
creates a piecewise linear step detector. But capacitive sensing techniques can
also operate as a pure linear function. This means a single sensor can sense
empty, full or anywhere in between.
The capacitive sensor creates or changes a time constant that controls an oscillator or pulse generator. Because current can be controlled or fixed at a set limit, the frequency of an oscillator directly reflects the relative level of the liquid.
The capacitive sensor creates or changes a time constant that controls an oscillator or pulse generator. Because current can be controlled or fixed at a set limit, the frequency of an oscillator directly reflects the relative level of the liquid.
Hydrostatic
Pressure:
Hydrostatic pressure
level sensors are submersible or externally mounted pressure sensors suitable
for measuring the level of corrosive liquids in deep tanks or water in
reservoirs. Sensors are commercially available from 10mbar to 1000bar. Where the sensor cannot be mounted to the
bottom of the tank or pipe thereof, a special version of the hydrostatic
pressure level sensor can be suspended from a cable into the tank to the bottom
point that is to be measured. The sensor must be specially designed to seal the
electronics from the liquid environment.
Requirement :
We need a wireless
sensor which can measure level of liquid in the tank and send the
status to the main processing unit
continuously.
Conclusion:
As the bogie will be moving and will be
operated by every type of people therefore the sensors which will be implemented must be rugged .As Ultrasonic level sensors are also affected
by the changing speed of sound due to moisture, temperature, and
pressures. Hence correction factors have to be applied to the level measurement
to improve the accuracy of measurement. Resistive type will be discarded as it
is depended on every connection of resister so as if any resister fails ,then
system can fails .Capacitive type can be preferred but it will need a
connections of wires either inside the
tank or from outside one more problem is of dielectric constant of water can change if it get contaminated by any means. So, in my opinion we should prefer pressure sensor which
will work on pressure exerted by water and can not be effected by any environmental
problems, also ,it can be mounted
outside the tank anywhere safely and easily.
Energy
Harvesting Technique
Portable devices and wireless sensors are conventionally powered
by chemical batteries. The use of batteries not only leads to their costly
replacement especially for sensors at inaccessible locations, but also causes
pollution to the environment. Besides, batteries also place limitation on the
miniaturization of micro- or nano- electromechanical systems.
Major Problem:
In our train application , we do not need wires as our bogie will be
always in moving condition hence wires can be damaged .Therefore if we are
using wireless sensor then to provide
the power supply we need a technology
By which we can provide power supply
without having power supply from main supply of bogie. This grows need of a harvesting technique which can provide
supply in efficient manner .
Benefits of Energy Harvesting
•
Long lasting operability
•
No chemical disposal
•
Cost saving
•
Safety
•
Maintenance free
•
No charging points
•
Inaccessible sites operability
•
Flexibility
We
have so many harvesting technique such as :
1) Solar Harvesting technique
2) Wind Harvesting technique
3) Vibration harvesting technique
1.Solar Harvesting Technique:
Sun
is a good source of energy .Solar energy can be used for providing power supply to the sensors. This include a
solar panel which generate energy using
sun rays and gives output as electric energy which can be used by the sensors.
Solar panels convert heat energy into electric energy.
2.Wind Harvesting technique :
The wind energy-harvesting device
that was explored for the energy harvesting application was a mini-wind
turbine. The wind turbine functions by converting mechanical energy from the
moving fan blades through a generator into electrical energy. The mini wind
turbine produces alternating current (AC). To convert from AC to DC (direct
current), a full wave rectifier is implemented to create usable power. The energy is sent through a power management circuit to
charge a super capacitor and output a constant 3.3 volts.
3.Vibration harvesting Technique:
The vibration energy harvester is composed of two piezo
wafers that generate power from the train’s harmonic vibrations. This product
requires no maintenance and is able to absorb low vibration frequencies. It has
a completely sealed enclosure to provide electrical insulation and protect its
components against the elements.
Conclusion :
In above three techniques, as per the requirement of train solar method can not be implemented
because for implementing this system we need a proper space for attaching the
solar panel which is too difficult and has certain limitation of environmental
conditions also.
Wind Harvesting technique cannot be
implemented because of the fan as the energy will be only generated if fan
rotates but it’s rotation decrease as time passes for which we should have to be concern about the
proper oiling and maintenance of the system but since we apply large number of
sensor in bogie so the maintenance of
such a huge number of fan is a
big task for INDIAN RAILWAYS .So
there is a problem of durability.
So,
we should prefer vibration technology
because in trains, during motion there are large number of movements, jerks and vibration hence, this
technology suits the train application
as we are converting disadvantage into advantage .
METHODS FOR WIRELESS
SENSORS COMMUNICATION
Bluetooth (over IEEE 802.15.1),
ZigBee (over IEEE 802.15.4), ANT and Wi-Fi (over IEEE 802.11) are three protocol
standards for short range wireless communications with low power consumption.
1.
ZIGBEE:
ZigBee is a technological
standard, based on IEEE 802.15.4 standard, which was created specifically for
control and sensor networks. ZigBee has been
designed to transmit slowly. It has a data rate of 250kbps (kilobits per
second)
.It is intended for 2.45 Ghz , 868 Mhz
and 915 Mhz Band. It is low in cost ,complexity & power consumption as compared
to competing technologies. It is intended to network inexpensive devices .Data rates
touch 250Kbps for 2.45Ghz ,40 Kbps 915Mhz and 20Kbps for 868Mhz band.
2.WI- FI:
Wireless-fidelity (Wi-Fi)
IEEE 802.11 wireless networking standard, which may be able to reduce its power
consumption: 802.11v and proprietary. Although Wi-Fi is a very efficient
wireless technology, it is optimized for large data transfer using high speed
throughput and not really suitable for coin cell operation. Some companies are
attempting to use Wi-Fi for HID devices, however special proprietary driver
software is required and only limited functionality can be achieved [10].
3.ANT:
ANT
is a low power proprietary wireless technology which operates in the 2.4GHz
spectrum. It was established in 2004 [3] by the sensor company Dynastream.
Typically, the ANT transceiver device is treated as a black box [4] and
shouldn’t require much design effort to implement a network. Its primary goal
is to allow sports and fitness sensors to communicate with a display unit, for
example a watch or cycle computer. It also typically operates from a coin cell.
ANT+ has taken the ANT protocol and made the devices interoperable in a managed
network, thereby guaranteeing all ANT+ branded devices work seamlessly [5].
Similar to LE, ANT devices may operate for years on a coin cell.
4.Bluetooth:
The aim of this technology is
to enable power sensitive devices to be permanently connected to the Internet.
LE sensor devices are typically required to operate for many years without
needing a new battery. They commonly us
e a coin cell , for example the popular CR2032.
We require a communication method in between sensors
and main processing unit.
Conclusion
:
ANT
is susceptible to bursting and continuous interference on its assigned channel
and with the Wi-Fi or household mobile
phones . ZigBee is easy to block
with a Wi-Fi access point [9] and networks must be planned to avoid placing the
two technologies together ANT is a good example of a technology that is already
in mass production and has begun to establish itself as the “sports and fitness”
technology.. Wi-Fi is normally intended for bulk traffic transfer at high
speed. ZigBee is power hungry compared
with the other radio technologies. So ,there are merits and demerits of each
technology therefore we can prefer any of the above technology.
Conclusion
I have given this report and
some suggestions for the technologies as per my study . I hope this report will
give a small help in the CDIS .CDIS is a intelligent system which will reduce man
power, hazardous accidents , and at the same instant will provide a sound information to passengers and to the
INDIAN RAILWAYS staff to be updated
.This system will definitely change the face of INDIAN RAILWAYS in the mind of people of India.
I hope , in the future, more parts of the coach and the engine will be added to this diagnosis system to get
more closer to the train environment . 
Ø NAME: PRABHAT KUMAR YADAV
EC DEPARTMENT (3rd
year)
Ø BLOG: prabhatpsit.blogspot.com
Ø PHONE NO. :8005176076 ,8563003215
Ø ADDERESS:28, PINK CITY COLONEY
MOHAAN
ROAD
LUCKNOW-226017
Ø COLLEGE: PRANVEER SINGH INSTITUTE OF TECHNOLOGY
BHAUNTI,
KANPUR
-208020
Many-Many Thanks to Gautam Sir, for his Support and Co- orperation.
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