tsunami warning system (synofsis)

Tsunami Warning System
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M.Sc I yr (Computer Science) Semester I
1. INTRODUCTION
The word tsunami is derived from Japanese, denoting port or harbor (tsu) and sea wave
(nami) caused by seismic activity. Tsunami is a wave in the ocean or in a lake that is
created by geologic event characterized by a series of waves with extremely long wave
length and long wave period. These gigantic waves are probably one of the most
powerful and destructive forces of nature. Tsunami may occur by earthquakes, submarine
Landslides, Volcanic eruption and meteorites striking the earth. Cases include geological
factors such as the landslide happen underwater plate earthquake and coastal areas as the
cause of the tsunami in the sea and submarine volcanic activity, submarine landslide was
caused by falling meteorites into oceanic later in the past have been confirmed. Usually
due to undersea tectonic dislocations, such as in geological faults along the deep ocean
trenches providing its energy, a tsunami can travel hundreds of miles over the open sea
and cause extensive damage when it encounters land and also called as tidal waves,
where it impacts with varying degrees of severity.
Since earthquakes cannot be predicted, Tsunami also cannot be predicted. But we can
forecast tsunami arrival times and wave heights through the use of computer modeling
after a tsunamigenic earthquake has been recorded.
After grasping the fundamentals, more realistic conditions for models of the ocean-earth
conditions are considered. These are treated by numerical methods finite-difference or
finite-element.
A tsunami warning system (TWS) is used to detect tsunamis in advance and issue
warnings to prevent loss of life and damage. Tsunami Warning System are much more
complicated even then tsunamis themselves, because people and instruments are alsoinvolved.
Totally six Tsunami Warning System exists worldwide: French, Russian, Japanese, Hawaiian,
Aleutian and Pacific. The system as a whole from detecting the seismic event to disseminating
warnings to activating sirens or other local notification devices is designed to work efficiently
and quickly to ultimately help save lives. The Tsunami Early Warning System comprises a
real-time network of seismic stations, Bottom Pressure Recorders (BPR), tide gauges and
24 X 7 operational warning centre to detect tsunamigenic earthquakes, to monitor

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tsunamis and to provide timely advisories following the Standard Operating Procedure
(SOP), to vulnerable community by means of latest communication methods with back-
end support of a pre-run model scenario database and Decision Support System (DSS).
The Warning Centre is capable of issuing Tsunami bulletins in less than 10 minutes after
any major earthquake in the Ocean thus leaving us with a response/lead time of about 10
to 20 minutes for near source regions and a few hours in the case of mainland.
The Tsunami Early Warning System (TWS) consists of two equally important
components i.e. networks of sensors to detect tsunamis and communication infrastructure
to issue timely alarms to permit evacuation of coastal areas.
Network of seismic monitoring station at sea floor detects presence of earthquake.
Seismic monitoring station determines location and depth of earthquake having potential
to cause tsunami. Any resulting tsunami are verified by sea level monitoring station such
as DART buoys, tidal gauge. Communication infrastructure to issue timely alarms to
permit evacuation of coastal areas.
TWS
Network of sensors Communication Infrastructure

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There are two distinct types of Tsunami Warning System (TWS) presently exist in the
world. They are “International Warning System” and “National Warning System”.
International Warning System - uses both data like seismic and water level data from
coastal buoys. Tsunami travel at 500-1000 km/hr, while seismic wave travel at 14,400
km/hr. This give sufficient time for tsunami forecast to be made. It is commonly used in
Pacific Ocean and Indian Ocean
National Warning System - use seismic data about nearby recent earthquakes to
determine if there is a possible local threat of a tsunami. Such systems are capable of
issuing warnings to the general public (via public address systems and sirens) in less than
15 minutes. Although the epicenter and moment magnitude of an underwater quake and
the probable tsunami arrival times can be quickly calculated.
It is almost always impossible to know whether underwater ground shifts have occurred
which will result in tsunami waves. As a result, false alarms can occur with these
systems, but the disruption is small, which makes sense due to the highly localized nature
of these extremely quick warnings, in combination with how difficult it would be for a
false alarm to affect more than a small area of the system. Real tsunamis would affect
more than just a small portion
International Warning System National Warning System

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There are two distinct types of National Warning System (NWS) exist. They are
“Tsunami Watches” and “Tsunami Warning”.
Tsunami Watches - a Tsunami Watch is automatically declared by the Tsunami
Warning Center (TWC) for any earthquake magnitude 7.5 or larger (7.0 or larger in the
Aleutian Islands) if the epicenter is in an area capable of generating a tsunami. Civil
Defense is notified, and the local media is provided with public announcements. TWC
then waits for data from tide gauge stations to confirm whether or not a tsunami has been
generated.
TWC also requests reports on wave activity from tide-gauge stations near the earthquake
epicenter. If the stations observe no tsunami activity, the Tsunami Watch is canceled. If
the stations report that a tsunami has been generated, a Tsunami Warning is issued. A
warning may be issued automatically if an earthquake powerful enough to create a
tsunami occurs nearby. The emergency broadcast system alerts the public of the danger,
and evacuation begins. Remember, tsunamis travel at 500 miles per hour; as soon as a
warning has been issued you should evacuate immediately.
Tsunami Warning - the objective of the Tsunami Warning System TWS is to detect,
locate, and determine the magnitude of potentially tsunamigenic earthquakes occurring in
the Ocean Basin or its immediate margins. Earthquake information is provided by various
seismic stations, National Earthquake Information Centre and international sources. If the
location and magnitude of an earthquake meet the known criteria for generation of a
tsunami, a tsunami warning is issued to warn of an imminent tsunami hazard. The
warning includes predicted tsunami arrival times at selected coastal communities within
National Warning System
Tsunami Watches Tsunami Warning

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the geographic area defined by the maximum distance the tsunami could travel in a few
hours.
If a significant tsunami is detected by sea-level monitoring instrumentation, the tsunami
warning is extended to the Ocean Basin. Sea-level (or tidal) information is provided by
NOAA's National Ocean Service, National Earthquake Information Centre, university
monitoring networks and other participating nations of the TWS. The International
Tsunami Information Centre, part of the Intergovernmental Oceanographic Commission,
monitors and evaluates the performance and effectiveness of the Tsunami Warning
System. This effort encourages the most effective data collection, data analysis, tsunami
impact assessment and warning dissemination to all TWS participants.

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2. OBJECTIVE
1. To detect tsunamis in advance and issue warnings to prevent loss of life and
property.
2. To help warn people about impending tsunami threats based on analysis of the
seismic event, or earthquake, and other data and models.
3. FEATURES
Features of tsunami are as follows:
All types of waves, including tsunami, have a wavelength, a wave height, amplitude, a
frequency or period, and a velocity. The physical characteristic of Tsunami is shown in
figure.
1. Wavelength: The distance between two identical points on a wave (i.e. between
wave crests or wave troughs) is called as wavelength. Normal ocean waves have
wavelengths of about 100 meters. Tsunami is usually having the longer wavelengths and
up to 500 kilometers.
2. Wave height: The distance between the trough of the wave and the crest or peak
of the wave is usually referred as wave height.

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3. Wave amplitude: The height of the wave above the still water line, usually this is
equals to 1/2 the wave height. Tsunami can have variable wave height and amplitude that
depends on water depth as we shall see in a moment.
4. Wave frequency: The amount of time it takes for one full wavelength to pass a
stationary point is called as wave frequency or wave period.
5. Wave velocity is the speed of the wave. Velocities of normal ocean waves are
about 90km/hr while tsunami have velocities up to 950 km/hr (about as fast as jet
airplanes), and thus move much more rapidly across ocean basins. The velocity of any
wave is equal to the wavelength divided by the wave period. V = λ/P
Features of Tsunami Warning System (TWS) are as follows:
1. Locate and characterize the earthquake’s source and its probability of creating a
tsunami via the collection of data from seismic networks.
2. Review automated earthquake analysis, and if necessary, modifies (by the duty
scientist or watch stander) the automated results.
3. Obtain continuous sea level data from tide gage sites, and where available, data
from Deep Ocean Assessment and Reporting of Tsunamis DART buoys, to verify the
existence of a tsunami and to calibrate models.
4. Prepare and disseminate information to appropriate emergency management
officials and others.

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4. WORKING
There are three ways for detecting the Tsunami.
1. Seismometers.
2. Coast Tidal Gauges.
3. DART Buoys .
1. A seismograph, or seismometer, is an instrument used to detect and record
seismic waves. Seismic waves are propagating vibrations that carry energy from the
source of an earthquake outward in all directions. They travel through the interior of the
Earth and can be measured with sensitive detectors called seismographs. Scientists have
seismographs set up all over the world to track the movement of the Earth’s crust.
Seismic waves are divided into two types: Body Waves and Surface Waves.
Body waves include P (compressional or primary) waves and S (transverse or secondary)
waves. An earthquake radiates P and S waves in all directions and the interaction of the P
and S waves with the Earth's surface and shallow structure produces.
Surface waves. Near an earthquake, the shaking is large and dominated by shear-waves
and short-period surface waves. These are the waves that do the most damage to our
buildings, highways, etc.
At farther distances the amplitude of the seismic wave’s decreases as the energy released
by the earthquake spreads throughout a larger volume of Earth. Also with increasing
Detecting the Tsunami
Seismometers Coastal tidal guage DART buoys

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distance from the earthquake, the waves are separated apart in time and dispersed because
P, S, and surface waves travel at different speeds.
Love waves and Rayleigh waves are surface waves.
Love waves are transverse waves that vibrate the ground in the horizontal direction
perpendicular to the direction that the waves are travelling. They are recorded on
seismometers that measure the horizontal ground motion.
Rayleigh waves are the slowest of all the seismic wave types and in some ways the most
complicated. Like Love waves they are dispersive so the particular speed at which they
travel depends on the wave period and the near-surface geologic structure, and they also
decrease in amplitude with depth. Typical speeds for Rayleigh waves are on the order of
1 to 5 km/s.
Generally, a seismograph consists of a mass attached to a fixed base. During an
earthquake, the base moves and the mass do not. The motion of the base with respect to
the mass is commonly transformed into an electrical voltage. The electrical voltage is
recorded on paper, magnetic tape, or another recording medium. The record written by a

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seismograph in response to ground motions produced by an earthquake or other ground-
motion sources is called seismogram.
Seismographs record a zig-zag trace that shows the varying amplitude of ground
oscillations beneath the instrument. This record is proportional to the motion of the
seismometer mass relative to the earth, but it can be mathematically converted to a record
of the absolute motion of the ground.
 Information available about source of tsunami is based on seismic information.
 Earthquake are measured based on its magnitude recorded by its seismograph.
When a tsunami event occurs, the first information available about the source of the
tsunami is based only on the available seismic information. Earthquake are measured
based on its magnitude recorded by a seismograph.
2. Coastal Tidal gauge
Tide gauge is a device for measuring sea level and detecting tsunami. Tide gauges that
are close to the earthquake would be able to detect the rise in the sea level that a tsunami
would produce.
There are fundamentally four types of sea level measuring technology in common use:
1. Stilling well and float: in which the filtering of the waves is done through the
mechanical design of the well.
2. Pressure systems: in which sub-surface pressure is monitored and converted to
height based on knowledge of the water density and local acceleration due to gravity.
Such systems have additional specific application to ocean circulation studies in which
pressure differences are more relevant than height differences.
3. Acoustic systems: in which the transit time of a sonic pulse is used to compute
distance to the sea surface.
4. Radar systems: similar to acoustic transmission, but using radar frequencies.

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Importance:
In order to confirm the tsunami waves following an earthquake, to monitor the progress
of tsunami and later for cancellation of warning, it is essential to monitor the coastal sea
level changes. A network of tide gauges may be the only way of detecting a Tsunami in
cases where seismic data is not available or when the Tsunami is triggered by events
other than an earthquake.
Each field station is equipped with two types of sensors in the tide gauge system:
Pressure sensors and acoustic sensors, to measure tide levels.
The pressure sensors can be fixed directly in the sea to monitor sub-surface pressure.
The sensor is connected by a cable that carries power and signal lines to an onshore
control and logging unit. The sensor is usually contained within a copper or titanium
housing with the cable entering through a watertight gland. Material used for the housing
is chosen to limit marine growth.

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The acoustic tide gauges depend on measuring the travel time of acoustic pulses
reflected vertically from the sea surface. This measurement is made with the acoustic
transducer mounted vertically above the sea surface, located inside a tube that provides
some degree of surface stilling and protects the equipment.
Each tide gauge measures the sea level by sampling for every one minute and transmits it
for every 5 minutes. The filed stations are equipped with necessary power and
communication facilities. The real time data from field stations is transmitted
simultaneously to the central receiving stations.
3. DART (Deep Ocean Assessment & Reporting Of Tsunami)
Each DART station consists of a surface buoy and a seafloor bottom pressure
recording (BPR) package that detects pressure changes caused by tsunamis. The surface
buoy receives transmitted information from the BPR via an acoustic link and then
transmits data to a satellite, which retransmits the data to ground stations for immediate
dissemination to NOAA's Tsunami Warning Centers, NOAA's National Data Buoy
Center, and NOAA's Pacific Marine Environmental Laboratory (PMEL).
When on-board software identifies a possible tsunami, the station leaves standard mode
and begins transmitting in event mode. In standard mode, the station reports water
temperature and pressure (which are converted to sea-surface height) every 15
minutes. At the start of event mode, the buoy reports measurements every 15 seconds for
several minutes, followed by 1-minute averages for 4 hours.
There are two types of DART system:
The first-generation DART I stations had one-way communication ability, and relied
solely on the software's ability to detect a tsunami to trigger event mode and rapid data
transmission. In order to avoid false positives, the detection threshold was set relatively
high, presenting the possibility that a tsunami with low amplitude could fail to trigger the
station.
The second-generation DART II is equipped for two-way communication, allowing
tsunami forecasters to place the station in event mode in anticipation of a tsunami's
arrival.

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Hardware Description
 Microcontroller
In this work, the pressure is induced using piston pump. The pressure is sensed using
capacitive proximity sensor and the raise in the pressure which is above the threshold
value is send as signal to the transmitter side microcontroller. Microcontroller used in this
work is AT89C2051. It is a 20 pin DIP. The AT89C2051 is a low voltage, high
performance CMOS 8-bit microcomputer with 2K bytes flash programmable and erasable
read only memory (PEROM). By combining a versatile 8-bit CPU with flash on a
monolithic chip, the Atmel AT89C2051 is a powerful microcomputer which provides a
highly flexible and cost-effective solution to many embedded control applications. The
AT89C2051 provides the following standard features: 2K bytes of flash, 18 bytes of
RAM, 15 I/O lines, two 16 bit timer/counters, and five vector low levels interrupt
architecture, a full duplex serial port, a precision analog comparator, on-chip oscillator
and clock circuitry. In addition, the AT89C2051 is designed with static logic for
operation down to zero frequency and supports two software selectable power saving
modes. The idle mode stops the CPU while allowing the RAM, timer/counters, serial port
and interrupt system to continue functioning. The power down mode saves the RAM
content but disables all other chip functions until the next hardware reset.
 Transmitter
The light source LED produces a light beam across the bottom of the coil. IR (infrared)
rays are chosen because there is less noise and ambient light than at normal optical
wavelengths. LED is used as transmitter and it uses Infrared rays to transmit the signals.
The transmitter module diagram

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Fig: Transmitter Module Diagram Fig: Receiver Module Diagram
In the transmitter module, the capacitive sensor senses the change in capacitance. If the
actual value exceeds the target value then it considers that there is some abnormal
condition. The value is given as interrupt signal on the port P3.2 of AT89C2051
microcontroller. As a result, the data signal and carrier signal are generated by the
microcontroller. Data signal is pulse code modulated with the carrier wave. Negative
pulse code modulation is performed. The signal is passed to receiver in the form of IR
rays with the help of LED.
 Receiver
TSOP 1738 is the receiver used in this study which has the capability to receive
frequency with the range of 38 kHz. TSOP 1738 is the standard IR remote control
receiver series, supporting all major transmission codes. The receiver module diagram is
shown in figure 5. In the receiver module, TSOP1738 receives the signal in the input pin.
This is given as input to another AT89C2051 microcontroller on the interrupt pin P3.2.
The PC is interfaced with the microcontroller through MAX-232 level converter, in order
to convert TTL logic to RS logic. In MAX-232 11th pin takes the microcontroller TTL
logic and process it and then gives the RS logic output on the 14th pin. The buzzer is
interfaced with the microcontroller on the port P1.5.
 Capacitive Sensor
Proximity capacitive sensor is used in this study. This sensor contains a dielectric
material separated by an electric plate and comparator. When there is any variation in

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capacitance value, the comparator compares the actual value with the target value. Based
on this principle, capacitive sensor gets operated.
 MAX-232 Level Converter
The MAX-232 level converter is a 16 pin DIP. It contains dual charge pump DC-DC
voltage converters, RS 232 drivers, RS 232 receivers and receiver and transmitter enable
control inputs.
 RS232
RS232 devices can be plugged straight into the computers serial port. This is referred to
as COM port. The data acquisition device used here is capacitive sensors. Its output is fed
through microcontroller. In warning phase mobile is connected to PC through the RS232
port.
Software Description
 Keilμvision2
This is used to compile the code written for the microcontroller. The microcontroller code
is written using embedded C. It encapsulates the following components:
• A project manager.
• A make facility.
• Tool configuration.
• Editor.
• A powerful debugger.
 Project Manager
A project is composed of all source files, development, tool options and directions
necessary to create a program. A single μVISION2 project can generate one or more
target programs. The source files used to create a target are organized into groups. The
development tools can be set at target, group, or file level.
 Integrated Utilities
The tools menu is used to start the user utilities within the μVISION2 IDE. A
configurable interface provides access to version control systems.
 Editor

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The μVISION2 editor includes all the editing features, color syntax, highlighting and text
indentation for the C source code. The editor is available while debugging the program
and this gives a natural debugging environment that lets to quickly test the application.
 Debugger
The debugging is performed through breakpoints. Its sets program breakpoints while
editing. Breakpoints are activated while starting the debugger. It may be set on
conditional expressions, International Journal of Embedded Systems and Applications
(IJESA) Vol.1, No.2, December 2011 72 or variable and memory access. Debug
functions can be executed when the breakpoints are triggered.
 PROGRAMING MICROCONTROLLER IN KEIL
The complex problems faced by the embedded software developers are solved by the keil
developing tools.
 When starting a new project, microcontroller to be used from the device database
should be selected and the μVISION IDE sets all compiler, assembler, linker and memory
options.
 The keil μVISION debugger accurately simulates on chip peripherals.
 To test the software with target hardware some adapter are used to download and
test program code on the target system.
 Cross Assembling
On writing programs for microcontrollers, cross assembler or cross compilers are used. A
cross assembler is an assembler that runs on the host system, but produces binary
instructions which is suitable for the target system. And a cross compiler works similar to
the cross assembler.
 VB .NET
VB.NET is the most productive tool for creating .NET applications. It provides the
following features:
• Common Language Runtime.
• Language Interoperability.
• Enhanced security.
• Simplified deployment.

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• Improved versioning support.
The controls used in this project include,
1. Microsoft Communication Control
2. Oxygen Mobile SMS Control
 Microsoft Communication Control
The Microsoft communication control provides serial communications for the application
by allowing the transmission and reception of data through a serial port. The Microsoft
communication control provides the following two ways for handling communications:
 Event Driven
Event driven communication is a very powerful method for handling serial port
interaction. When a character arrives or a change occurs in the Carrier Detect (CD) or
Request to Send (RTS) lines then they are notified immediately. In such cases, the
Microsoft communication International Journal of Embedded Systems and Applications
(IJESA) Vol.1, control’s On Communication events are used to trap and handle these
communication events. The On Communication event also detects and handles
communications errors.
 Polling for Events
Polling for events and errors are done by checking the value of the COM Event property
after each critical function of the program. This may be preferable if the application is
small and self-contained.
 Oxygen Mobile SMS ActiveX control
This project uses the oxygen mobile SMS control OCX to send SMS to the destination
user via Simple Message Service. Oxygen Mobile ActiveX Control is designed to give an
access to various Nokia phone capabilities from a Windows program. Oxygen Mobile
ActiveX Control has modules messaging and are independent to each other and can be
used together or separately from each other. Each module or their combination has
methods for establishing phone connection and retrieving basic phone parameters like
model internal name, software and hardware versions, and signal and battery levels of the
phone. To work with Oxygen Mobile ActiveX Control Com Number should be set and
Connection Mode properties, call Open method should also be specified. When

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connection is established phone is ready to work. To close connection to the phone, call
Close method must be used. The following flowcharts illustrate the Tsunami warning
system.
Transmitter Side Flow during Detection Receiver Side Flow during Detection
Fig: basic steps followed during initiation Fig: Update Settings “command button

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Fig: operations performed during form load
The microcontroller is programmed with embedded C language, compiled using keil
compiler and the verified program was fused into microcontroller using the
microcontroller burner. Then the pressure variations are sensed using capacitive
proximity sensor and then providing warnings using mobile by means of oxygen Mobile
SMS Control. Based on the pressure changes under the sea, Tsunami could be detected in
advance
5. ADVANTAGES
 Deep water pressure produce low false reading
 Multiple sensors can detect wave propagation.
 Good advance warning system.
DISADVANTAGE
 Expensive equipments.
 High maintenance cost.
 Require multiple communication links: SONAR. Satellite Uplink.
Satellite Downlink. Notification to authorities. Authorities notify coastal
dwellers.

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6. CONCLUSION
The phenomena of tsunamis, their origin, generation, travel, and terminal effects have
been described. As these life-threatening oceanic processes are being better understood,
so precautionary methods and warning systems are being developed. There still remains a
great deal of uncertainty as to whether any major tsunami would result from a large
earthquake near the coast. The possible arrival time at distant locations can readily be
predicted, whereas the degree of danger it might present would not be predictable with
certainty.
In efforts to provide timely warnings, quite often the very effects warned against might
not happen at all. This, coupled with the unpredictability of major earthquakes, has led
the public to distrust and even be callous toward tsunami-warning systems. Nevertheless,
these phenomena do occur, creating intensive widespread damage, and inhabitants of
exposed coastal regions can never be totally immune to tsunami attack. For this reason,
time and money devoted to developing and maintaining global tsunami-warning systems
are to be considered well spent.
7. FUTURE SCOPE
In future Tsunami occurrence can be decided and alarm can be raised only after checking
many criteria. Four criteria to be checked out are as follows:
• Pressure inside the sea bed.
• Tide level.
• Biological changes in the marine living organisms.
• Sea shore level.
If all these four criteria get detected then it can be concluded that there is some
occurrence of natural disaster (Tsunami).

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8. REFERANCE
 http://en.wikipedia.org/wiki/Tsunami_warning_system
 http://seminarprojects.net/t-tsunami-warning-system
 http://www.authorstream.com/Presentation/aSGuest132268-1389817-ppt-for-seminar-
tsunami-alarm
 http://www.tsunamiterror.info/future_proposed.html
 http://geography.about.com/od/physicalgeography/a/tsunami_2.html
 https://en.wikipedia.org/wiki/Seismometer
 http://www.hilo.hawaii.edu/~nat_haz/tsunamis/watchvwarning.php
 http://www.sms-tsunami-warning.com/pages/seismograph#.VeNe4iWqqkq
 https://en.wikipedia.org/wiki/Tide_gauge
 https://en.wikipedia.org/wiki/Deep-ocean_Assessment_and_Reporting_of_Tsunamis
 http://earthweb.ess.washington.edu/tsunami/general/warning/warning.html
 http://www.slideshare.net/2507052220/tsunami-warning-system-
31764975?qid=59f7a842-665f-4d79-8cb2-56fd8f84b1bb&v=qf1&b=&from_search=1
 http://www.slideshare.net/sasidevi984/tsunami-warning-system-46599481?qid=f17cefab-
e63a-433d-a1a4-1fcbed0b4bd0&v=default&b=&from_search=9
 http://airccse.org/journal/ijesa/papers/1211ijesa06.pdf
a

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