Technical Specifications | |
|---|---|
| Engine: | 149.2cc |
| Power: | 14.4ps@8500rpm |
| Torque: | 12.80nm@6500rpm |
| Weight: | 146.00 |
| Clearance: | 145.00 |
| Fuel Tank: | 12.40 |
| Wheelbase: | 1325.00 |
| Gears: | 5 Speed |
| Top Speed: | 120 |
| Brakes: | Disc |
| Fuel Economy: | 50 |
Features | |
| Fuel Guage: |  |
| Self Start: | |
| Tacho Meter: | |
| Trip Meter: | |
| Stand Alarm: |  |
| Alloys: | |
Need for Speed: ProStreet will take the Need for Speed series in a new direction of gameplay. Instead of an arcade style of gameplay which has dominated the series, ProStreet will focus much more on realism and move closer to, but not into, racing simulation, and still with options to use driving assistants to make driving easier and more arcade-like. Unlike its predecessors, all racing in ProStreet will take place on closed tracks, thus making it the first game in the series not animating illegal racing behaviour, hence there will not be any police in the game. Performance tuning will take up a large part of gameplay in a way that even a small adjustment of the shape of a car's body will impact its performance. Autosculpt is back from Carbon, but with much greater detail. According to an Electronic Arts employee, there will be thousands of aftermarket upgrades, visual and performance, from real performance brands.[3]
In ProStreet there will be several different game modes, including Drag, Grip, Speed, and Drift. Drag race is simply a 1-mile drag race, the first to cross the finish line wins. Grip race, which is a circuit race, you do whatever you need to do, to cross the finish line first. Block your opponent, ram them, or even smash them off the track. Speed challenge is all about speed and control, you need to pass the checkpoints with highest possible speed, and the racer with the highest total checkpoint speed wins. Drift, you just drift for points.
ProStreet will feature next-generation graphics aiming for a more photo-realistic feel, and more advanced physics. It will also be the first Need for Speed game to include damage modelling since 2000's Need for Speed: Porsche Unleashed. The new damage system is said to be very accurate, as a collision with any object in the game world may render a car damaged or even useless.[3]
Also, in accordance to the fact that Autosculpting any body parts will impact performance, these changes can be tested in an enclosed chamber marked as the "Wind Tunnel". Your car is placed in the Wind Tunnel and artificial winds are created, giving you your performance on the track. You can use this to tune your car to your liking.
The new ProStreet will also feature an advanced damage system, which will directly impact on your car's performance, unlike previous Need for Speed titles. This is especially significant in the Speed racing mode, as you can easily "total" your car.
As before, the game will feature an online mode. However, unlike previous Need for Speed titles, it will be much more integrated into the game; as long as a player is connected to the Internet and logged in, his/her in-game progress will be recorded for the purpose of online leaderboards. A player's custom-built cars can also be shared online via "blueprints", with the creator being given credit whenever their car setup is used for a leaderboard.[4]
Online modes will not be available in the PlayStation 2 version of the game.
The official title was leaked several months before the official announcement. Soft Club, the Russian distributor of the game, unveiled the name and release date of the game in February 2007.[5] EA had not until the official announcement on May 31, 2007, given any clue about the game's title.
There will be over 60 cars from around 26 manufactures included in ProStreet. Only eight of these are supercars, making them relatively rare, as in real life. The game will also feature the new Nissan GT-R PROTO.[6][7]
a. ABSORBABLE: Those that are absorbed or digested by the body cells and tissue fluids in which they are embedded during and after the healing processes.
SURGICAL GUT: The most commonly used absorbable suture material. Derived from the small intestine of healthy sheep. It is uniformly fine-grained and possesses great tensile strength and elasticity.
DEXON (POLYGLYCOLIC ACID): Widespread absorbable suture material of a synthetic, braided polymer. Dexon has low rate of reactivity and infection rate, and has excellent knot security and tensile strength. A drawback of Dexon is its high friction that binds and snags when wet.
CHROMIC SUTURE MATERIAL: Chromic suture materials have undergone various intensities of tanning with the salt of chromic acid to delay the tissue absorption time. Typical examples of chromic suture and absorption times are:
Type A: Plain, 10 days
Type B: Mild chromic, 20 days
Type C: Medium chromic, 30 days
Type D: Extra chromic, 40 days
b. NON-ABSORBABLE: Those suture materials that can not be absorbed by the body cells or fluids.
NYLON (ETHILON): Of all the non-absorbable suture materials, monofilament nylon is the most commonly used in surface closures. It has minimal tissue reactivity and resists inflections greater when compared to braided suture materials. It has a high tensile strength that ensures wound security. The disadvantage of nylon is the difficulty in achieving good knot security. Because of this at least 4-5 "throws" (knots) are required to achieve a secure knot.
PROLENE: Polymer polypropylene (Prolene) appears to be stronger then nylon and has better overall wound security. However, it has a greater memory (returns to its packaging shape) and is more difficult to work with.
BRAIDED: These include cotton, silk, braided nylon and multifilament Dacron. Until the advent of synthetic fibers, silk was the mainstay of wound closure. It is the most workable and has excellent knot security. Disadvantages: high reactivity and infection due to the absorption of body fluids by the braided fibers.
b. SUTURE SIZES: The size of suture material is measured by its width or diameter and is vital to proper wound closure. As a guide the following are specific areas of their usage:
1-0 and 2-0: Used for high stress areas requiring strong retention, i.e. - deep
fascia repair
3-0: Used in areas requiring good retention, i.e. - scalp, torso, and hands
4-0: Used in areas requiring minimal retention, i.e. – extremities. Is the most common size utilized for superficial wound closure.
5-0: Used for areas involving the face, nose, ears, eyebrows, and eyelids.
6-0: Used on areas requiring little or no retention. Primarily used for cosmetic effects.
c. SURGICAL NEEDLES: There are a variety of needles for wound closure. Curved needles have two basic configurations; tapered and cutting. For wound and laceration care, the reverse cutting needle is used almost exclusively. It is made in such a way that the outer edge is sharp so as to allow for smooth and atraumatic penetration of tough skin and fascia. Tapered needles are used on soft tissue, such as bowel and subcutaneous tissue, or when the smallest diameter hole is desired.
d. SURGICAL INSTRUMENTS: It is not necessary to have large numbers of instruments for emergency wound care. Wounds and lacerations can be managed with the following instruments:
NEEDLE HOLDERS: Needle holders come in various sizes and shapes, but for most lacerations a standard size 4" will complete the task. For larger, deeper wound closures a larger needle and needle holder may be required.
FORCEPS: Grasping and controlling tissue with forceps is essential to proper suture placement. However, whenever force is applied to skin or other tissues, inadvertent damage to cells can occur if an improper instrument or technique is used. Be gentle when grasping tissue, and never fully close the jaws on the skin.
SCISSORS: There are three types of scissors that are useful in minor wound care.
IRIS SCISSORS: Iris scissors are predominantly used to assist in wound debridement and revision. These scissors are very sharp and are appropriate in situations that require very fine control. They are very delicate and are not recommended for cutting sutures. However, when very small sutures require removal they can be use.
DISSECTION SCISSORS: Used for heavier tissue revision as necessary for wound undermining.
SUTURE REMOVAL SCISSORS: Standard 6-inch, single blunt-tip, suture scissors are most useful for cutting sutures, adhesive tape, and other dressing materials. Because of their size and bulk, these scissors are very durable and practical.
HEMOSTATS: Hemostats have three functions in minor wound care: clamping small blood vessels for hemorrhage control, grasping and securing facia during debridment, and are an excellent tool for exposing, exploring and visualizing deeper areas of the wound.
KNIFE HANDLES AND BLADES: The knife handle holds the blade and is used in the debridment and excisions during wound revision. Common blades are the #10 blade (used for large excisions), #15 blade (small, versatile and well suited for precise debridement and wound revision), and the #11 blade (ideal for incision and drainage of superficial abscesses and the removal of very small sutures).
e. ANESTHETIC AGENTS: Prior to suturing of wounds a thorough understanding of the properties of anesthetic solutions and injection techniques is required. The choice of anesthetics and techniques are individualized for every patient in relationship to severity of wounds, location of wounds, and allergic reactions; which could lead to anaphylactic shock.
f. ANESTHETIC SOLUTIONS
1. LIDOCAINE (XYLOCAINE): Lidocaine is the most commonly used anesthetic solution. It has a rapid on-set in local infiltration. Duration of action is approximately 75 minutes; though some patients appear to metabolize Lidocaine very rapidly and require repeated injections.
STRENGTH: 0.5%, 1.0%, & 2.0%
DOSE: Maximum individual dose should not exceed 5mg/kg, not exceeding 300mg
2. LIDOCAINE (XYLOCAINE WITH EPINEPHRINE): The same as Lidocaine, but contains epinephrine, which provides vasoconstriction, decreased bleeding, and prolongs the duration of the anesthetic effect.
STRENGTH: 0.5% & 1.0%
DOSE: Maximum individual dose 7mg/kg not exceeding 500mg.
CAUTIONS: Due to its vasoconstriction properties never use Lidocaine with epinephrine on: EYES, EARS, NOSE, FINGERS, TOES, PENIS, or SCROTUM
3. MEPIVACAINE (CARBOCAINE): Widely used as an emergency wound anesthetic. It has a slower on-set then Lidocaine but the duration is 30 to 60 minutes longer than Lidocaine.
STRENGTH: 1%
DOSE: Maximum individual dose 5mg/kg
4. BUPIVACAINE (MARCAINE): Although it is a very effective anesthetic its chief drawback is that is has a slow onset of action (10 - 15 minutes). The main advantage of bupivacaine is its duration of action, which is considerably longer then Lidocaine and mepivacaine.
STRENGTH: 0.25%
DOSE: Maximum individual dose 3mg/kg
g. INJECTION TECHIQUES: There are a large variety of needles and syringes available to deliver local anesthetics. For local, direct, and parallel wound infiltration, a 25, 27, or 30-gauge needle can used. Depending upon the amount of anesthetic required a 6 or 10 cc syringe will suffice. A key principle in the use of local anesthetics is to always aspirate the syringe before injection to check for blood return. Other guidelines include:
Check for allergies
Insert the needle at the inner wound edge
Aspirate to ensure infusion does not take place in an artery or vein
Inject agent into tissue and slowly withdraw (forming a small wheel at wound edge)
Avoid high pressure injections as they damage and distort tissue
Test the site in approximately 10 minutes, by touching the area around the wound (ask patient if the sensation is "sharp or dull")
After anesthesia has taken effect, suturing may begin
h. SUTURING PROTOCOL: The attending Medical Officer (MO) is ultimately responsible for the evaluation, cleaning, suturing, dressing, and overall management of wounds and lacerations. Hospital corpsmen will suture only upon his/her direction and only when subject corpsmen has current suture certification training.
i. MEDICAL OFFICER: Prior to suturing, the MO will:
Inspect and evaluate wounds and lacerations
Dictate the nature of treatment to be rendered, to include
Type of suture material used, if any
Type of stitch
Type and amount of anesthesia used
Type of dressing applied
Determine the need for radiographic studies
Order tetanus prophylaxis
Provide orders and instruction regarding dressing changes, suture removal and further follow up care.
j. HOSPITAL CORPSMEN: Once inspected and evaluated the attending MO will issue orders and instructions to the corpsman regarding the nature of treatment, cleansing materials, type of stitch, anesthesia, and dressing. The following wounds will not be sutured by Hospital Corpsmen
Wounds or lacerations with nerve, tendon or major vessel involvement.
Wounds or lacerations of the eye, eyelids, bites, and other severely contaminated wounds.
Wounds entering the thoracic or abdominal cavities.
k. WOUND EVALUATION: In most circumstances wounds penetrating the epidermis and dermis, with involvement of subcutaneous fat will require suturing. Before suturing take in to account the following factors:
Time of incident - most wounds will not be closed if 12 hours have past from time of injury.
Size of wound.
Depth of wound.
Tendon/nerve involvement.
Bleeding at site.
l. CONTRAINDICATIONS
If there is reddening and edema of the wound margins
Infection manifested by discharge or pus
Persistent fever or toxemia
Puncture wounds or animal bite
Tendon, verve, or vessel involvement
Any wound more than 12 hours old. With the exception of the face and hands
m. CLOSURE TYPES: There are three types of closure when determining wound repair: primary closure, secondary closure, and tertiary closure (delayed).
PRIMARY CLOSURE (PRIMARY INTENTION): Primary closure can only be done on lacerations that are relatively clean and minimally contaminated, with minimal tissue loss. Repair is usually necessary within 8-12 hours from the time of injury.
SECONDARY CLOSURE (SECONDARY INTENTION): Skin ulceration, abscess cavities, punctures, animal bites, and large tissue losses are often best left to heal by secondary intention. They are not primarily closed with sutures but are allowed to gradually heal by granulation of the epithelial tissues and then sutured as required.
TERTIARY CLOSURE (DELAYED PRIMARY CLOSURE): These are wounds that are too contaminated to close primarily. Wounds that fall into this category are often older, excessively contaminated with soil, feces (caused by human or animal bites), or the result of high-velocity missiles wounds. Once casuistry effects or infection have passed (4 to 5 days), normal closure can take place.
n. WOUND PREPARATION: Wound preparation is the most important step for reducing the risk of wound infection. It is essential that all contaminants and devitalized tissue be removed prior to wound closure. If not, the risk of infection and of a cosmetically poor scar are greatly increased.
o. PERSONNEL PRECAUTIONS: Because the process of preparing, cleaning, and suturing a wound brings personnel into contact with blood and other secretions, it is recommended that appropriate protective gloves and eyewear be worn at all times. The main infective agents that are of concern in these settings are hepatitis B and the human immunodeficiency virus (HIV). Refer to reference 4 (HM3 & 2) Chapter 5, for aseptic technique.
p. WOUND CLEANSING SOLUTION: Clean the wound area by using normal saline solution or other solutions such as Chlorhexidine or Hexachlorophene. Avoid betadine or alcohol.
q. WOUND SCRUBBING: Scrubbing the wound will assist in loosening debris and contaminates from the site.It is essential to be gentle and to start at the wound itself. The motion should be circular, with gradually larger circles away from the wound.
r. IRRIGATION: Wound irrigation is probably the most effective way to remove debris and contaminants. Method of irrigation is through an 18-gauge plastic catheter attached to a 30 to 50 cc syringe. Irrigate 1-2 inches from the wound refilling as necessary to achieve maximum reduction of wound contaminants.
s. DEBRIDEMENT: In spite efforts to cleanse and irrigate the wound, gross contaminants can still remain adhered to the injured tissues. If this occurs, sharp debridement should be carried out prior to closure. Removal of imbedded or adherent debris or dead tissue can be accomplished with tissue scissors or by scalpel excision.
t. BASIC LACERATION REPAIR - PRINCIPLES AND TECHNIQUES: Each wound and laceration has different technical requirements that have to be met in order to properly effect closure. During closure, every attempt is made to match each layer evenly and produce a wound edge that is evenly matched.
DEFINITION OF TERMS: Several techniques and maneuvers used in wound care are referred to by terms that can be confusing. These term are defined below:
BITE: The amount of tissue taken when placing the suture needle in the skin or fascia. The farther away from the wound edge that the needle is introduced into the epidermis, for example, the bigger the bite will be.
THROW: Each suture knot consists of a series of throws. In general you will need 3 or 4 throws per suture to ensure knot security. Some suture materials require more, such as nylon.
PERCUTANEOUS (DEEP) CLOSURE: Sutures, usually of a nonabsorbable material, that are placed in the skin with the knot on the surface.
DERMAL CLOSURE: Sutures, usually of an absorbable material, that are placed in the superficial (subcutaneous) fascia and dermis with the knot buried in the wound.
INTERRUPTED CLOSURE: Single sutures, tied separately, whether deep or percutaneous. For lab procedures and training, you will be using this type of closure.
CONTINUOUS CLOSURE (RUNNING SUTURES): A wound closure effected by taking several bites that are the full length of the wound, without tying individual knots. Knots are tied only at the beginning and end of the closure to secure the material.
SUTURE TECHNIQUES:
Wound layers should be placed in close approximation.
Minimal amount of tension across the suture line.
Wound edges should be slightly everted.
Equal bites, horizontally and vertically are important for wound position and healing.
Debride devitalized tissue.
3. SUTURE PROCEDURES
Apply the needle to the needle driver approximately one quarter the distance from the blunt end of the needle.
The needle should enter the skin with a 1/4-inch bite from the wound edge at a 90-degree angle.
Release the needle from the needle driver and reach into the wound and grasp the needle with the needle driver and pull it free so that you have enough suture material to enter the opposite side of the wound.
Use the forceps and lightly grasp the skin edge and arc the needle through the opposite edge inside the wound edge taking equal bites.
Release the needle and grasp the portion of the needle protruding from the skin with the needle driver. Pull the needle through the skin until you have approximately 1 to 1/2-inch suture strand protruding form the bites site.
Release the needle from the needle driver and wrap the suture around the needle driver two times.
Grasp the end of the suture material with the needle driver and pull the two lines across the wound site in opposite direction (this is one throw).
Do not position the knot directly over the wound edge.
Repeat 3-4 throws to ensuring knot security. On each throw reverse the order of wrap.
Cut the ends of the suture 1/4-inch from the knot.
The remaining sutures are inserted in the same manner.
4. FOLLOW-UP CARE
Following the placement of the sutures cleanse the suture site with normal saline.
Apply a small amount of Bacitracin and cover with an appropriate size sterile non-adherent dressing.
Depending on nature and extent of the wound, antibiotic therapy or Tetanus Toxoid way be indicated.
Attending MO will provide orders and instructions regarding dressing changes, suture removal, and further follow-up care.
Inform the patient theta the suture site needs to be checked in approximately 24 hours for signs of infection or complications.
5. SUTURE REMOVAL
TIME FRAME FOR REMOVING SUTURES: Times will vary according to the location and depth of the wound. However, the average time frame is 7-10 days after application. The following general rules can be sued in deciding when to remove sutures:
FACE: 4-5 days.
BODY & SCALP: 7 days.
SOLES, PALMS, BACK OR OVER JOINTS: 10 days
Any suture with pus or signs of infections should be removed immediately.
Once MO determines that the sutures should be removed, a suture removal kit, consisting of scissors and a pair of tweezers is utilized to remove the sutures.
Using the tweezers, grasp the knot and snip the suture below the knot with the scissors as close as possible to the skin.
Pull the suture line through the tissue and place on a 4x4.
Once all sutures have been removed count the sutures.
The number of sutures needs to match the number indicated in the patient's health record.
The new version of the Cedia will be called Cedia Select. The dual fuel car is powered by petrol and LPG.
The fifth largest automaker in Japan, Mitsubishi Motors Corporation stands thirteenth globally. Founded in April, 1970, the company has its headquarters in Tokyo, Japan. Strategic alliances saw the company perform strongly in the 1970s and the '80s during which period it increased its production capacity to over 1.5 million units. In a JV with HM, the company's Indian endeavour began with the Lancer which sold well and also posed quite a challenge to the Honda City. This led the company to introduce models like the globally successful SUV, the Pajero and later the Cedia and Montero. Mitsubishi in India has been unable to mirror the success of the Lancer and finds itself in a tough situation today since even the service costs are higher compared to its direct rivals. Having seen its premium sedan and the SUVs not performing as per expectations, maybe a good small car could turn the tables around for them.
Mitsubishi's Cedia never exactly set fire to the charts in India. Sure it is a popular car abroad, but with a more powerful engine. The detuned Cedia has been a rare sight on Indian roads, quite unlike its older sibling the Lancer. Mitsubishi know plans to change all that with the launch of the dual fuel Cedia Select.
In milieage-conscious India, diesels and dual-fuel cars have seen reasonable success, the diesel versions often cannibalising the original petrol variants. In the recent past, Maruti offered a dual-fuel Wagon R.
The company said today that the duel-fuel kits in the Cedia Select will be factory fitted, utilise the sequent-type technology for effective performance on LPG fuel and will have a 32-bit microprocessor. The Cedia Select cars would be priced at rs 8.6 lakh, ex-showroom
Dimensions & Weights
Overall Length 3520 mm
Overall Width 1475 mm
Overall Height 1660 mm
Wheel Base 2360 mm
Ground Clearance 165 mm
Front Track 1295 mm
Rear Track 1290 mm
Front Headroom 1040 mm
Front Legroom 985 mm
Rear Legroom 890 mm
Rear Shoulder 1200 mm
Boot Space liter
Kerb Weight 885 kg
Gross Vehicle Weight 1250 kg
No of Doors 5 door
Capacity
Seating Capacity 4 person
Fuel Tank Capacity 35 liter
Fuel Efficiency
Mileage (Highway) 17 km/liter
Mileage (City) 11.9 km/liter
Mileage (Overall) 12.9 km/liter
Performance
Maximum Speed 145 Km/Hour
0-100kmph 17.4 seconds
1/4 Mile 21.2 seconds
100kmph-0 (Braking) 72.3 meters
80kmph-0 (Braking) 55.2 meters
Engine
Engine Type/Model FC Engine
Displacement 1061 cc
Power 67 PS @ 6200 rpm
Torque 84 Nm @ 3500 rpm
Valve Mechanism
Bore 68.5 mm
Stroke 72 mm
Compression Ratio 9:1
No of Cylinders 4 cylinder
Cylinder Configuration Inline
Valves per Cylender 4 valve
Ignition Type
Engine Block Material
Block Head Material
Fuel Type LPG
Fuel System MPFI
Transmission
Transmission Type Manual
Gears/Speeds 5 Gears
Clutch Type
Final Reduction Gear Ratio
Suspensions
Front Suspension McPherson Strut with torsion type roll control device
Rear Suspension Coil spring, gas-filled shock absorbers with three link rigid axle and isolated trailing arms
Steering
Steering Type Electronic Power Steering
Power Assisted Standard
Minimum Turning Radius 4.6 meter
Brakes
Brake Type 8" Booster-assisted
Front Brakes Disc
Rear Brakes Drum
Wheels & Tyres
Wheel Type steel
Wheel Size 13 inch
Tyres 155/80 R13
Comfort
* Air Conditioner with Heater
* Rotary AC Controls
* 3-Spoke Steering Wheel
* Electronic Power Steering
* Smart Gear Knob
* Full Flat Front Seat
* Folding Rear Seat
* Remote Fuel Lid Opener
* Central Door Locking (4 doors)
* Provision for Parcel Shelf
* Key FOB with S Badging
* Remote Tail Gate Opener
Exterior
* Swept-back Headlamps
* Sporty Tail Lamps
* Aggressive Grille
* Attractive Bonnet
* Wide Bumpers
* Provision for Fog Lamps (Front)
* Flared Fenders
* Clear Side Indicators
* Stylish Tail Gate & Glass
* Outside Rear View Mirror (R,L) both
* Tinted Glass
* Wheel Hub Cap
* Front Wiper (2 speed + Intermittent)
* Radial Tyres
* Roof Rails
* Vibrant New Colours
* Bold New Badging
Interior
* Moulded Roof Lining
* Moulded Floor Carpet
* Luggage Compartment Carpet
* Door Trim Fabric
* Front Door Arm Rest
* Cabin Lamps (3 positions)
* Lower Console Box
* Assist Grip (3 nos.)
* Front Seat Back Pocket (Driver's Side)
* Racy Speedometer
* Electronic Trip Meter
* Ergonomic Seat Design
* Single Rear Seat
* Front Seat Head Rest
* Stylish Rear Seat Head Rest
* Reclining and Sliding Front Seats
* Plush Upholstery
* Front Ashtray
* Front and Rear Door Pocket
* Cup Holder
Safety
* Side-Impact Beams
* Collapsible Steering Column
* 8" Booster-assisted Brakes
* Child-proof Rear Door Locks
* Halogen Headlamps
* Front & Rear Seat Belt (3 point ELR)
* Ability to Diagnose Breakdown
* Unique High Mount Stop Lamp
* Headlamp Leveling Device
Bajaj auto is quite sense able on safety issues, thats why Bajaj auto install safety features fir LPG bikes which take care the leakage of gas or cylinder overheating. Bajaj will test platina LPG version before launch, currently 50units of the platina LPG are under test condition which will run on both LPG and petrol. Platina LPG version drops power approximately 20% which is huge hurdle and effect performance hardly. The performance loss will be reduced by adding additives which increase octane number and enhance performance of bike.
The normal petrol Bajaj Platina cost Rs 35,344 and platina LPG cost Rs5000 more,but running cost will be lower by 35-40 per cent than normal petrol Bajaj Platina and this saving will cover extra cost of bike.
TSUNAMI
A tsunami (IPA: /(t)sʊˈnɑːmi/) is a series of waves created when a body of water, such as an ocean, is rapidly displaced. Earthquakes, mass movements above or below water, volcanic eruptions and other underwater explosions, landslides, large meteorite impacts and testing with nuclear weapons at sea all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable to devastating. The term tsunami comes from the Japanese words (津波、つなみ) meaning harbor ("tsu", 津) and wave ("nami", 波). [a. Jap. tsunami, tunami, f. tsu harbour + nami waves. - Oxford English Dictionary]. For the plural, one can either follow ordinary English practice and add an s, or use an invariable plural as in Japanese. The term was created by fishermen who returned to port to find the area surrounding their harbor devastated, although they had not been aware of any wave in the open water. Tsunamis are common throughout Japanese history; approximately 195 events in Japan have been recorded.
A tsunami has a much smaller amplitude (wave height) offshore, and a very long wavelength (often hundreds of kilometers long), which is why they generally pass unnoticed at sea, forming only a passing "hump" in the ocean. Tsunami have been historically referred to as tidal waves because as they approach land, they take on the characteristics of a violent onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean (with which people are more familiar). Since they are not actually related to tides the term is considered misleading and its usage is discouraged by oceanographers.
Causes
Generation of a tsunami
A tsunami can be generated when the plate boundaries abruptly deform and vertically displace the overlying water. Such large vertical movements of the Earth’s crust can occur at plate boundaries. Subduction earthquakes are particularly effective in generating tsunami. Also, one tsunami in the 1940's in Hilo, Hawaii, was actually caused by an earthquake on one of the Aleutian Islands in Alaska. That earthquake was 7.8 on the Richter Scale.
Tsunami are formed as the displaced water mass moves under the influence of gravity and radiates across the ocean like ripples on a pond.
In the 1950s it was discovered that larger tsunami than previously believed possible could be caused by landslides, explosive volcanic action, and impact events when they contact water. These phenomena rapidly displace large volumes of water, as energy from falling debris or expansion is transferred to the water into which the debris falls. Tsunami caused by these mechanisms, unlike the ocean-wide tsunami caused by some earthquakes, generally dissipate quickly and rarely affect coastlines distant from the source due to the small area of sea affected. These events can give rise to much larger local shock waves (solitons), such as the landslide at the head of Lituya Bay which produced a water wave estimated at 50 – 150 m and reached 524 m up local mountains. However, an extremely large landslide could generate a “megatsunami” that might have ocean-wide impacts.
The geological record tells us that there have been massive tsunami in Earth's past.
Signs of an approaching tsunami
There is often no advance warning of an approaching tsunami. However, since earthquakes are often a cause of tsunami, an earthquake felt near a body of water may be considered an indication that a tsunami will shortly follow.
When the first part of a tsunami to reach land is a trough rather than a crest of the wave, the water along the shoreline may recede dramatically, exposing areas that are normally always submerged. This can serve as an advance warning of the approaching crest of the tsunami, although the warning arrives only a very short time before the crest, which typically arrives seconds to minutes later. [2] In the 2004 tsunami that occurred in the Indian Ocean the sea receding was not reported on the African coast or any other western coasts it hit, when the tsunami approached from the east.
Tsunamis occur most frequently in the Pacific Ocean, but are a global phenomenon; they are possible wherever large bodies of water are found, including inland lakes, where they can be caused by landslides. Very small tsunami's, non-destructive and undetectable without specialized equipment, occur frequently as a result of minor earthquakes and other event
WARNING AND PREVENTION
A tsunami cannot be prevented or precisely predicted, but there are some warning signs of an impending tsunami, and there are many systems being developed and in use to reduce the damage from tsunami.
In instances where the leading edge of the tsunami wave is its trough, the sea will recede from the coast half of the wave's period before the wave's arrival. If the slope is shallow, this recession can exceed many hundreds of meters. People unaware of the danger may remain at the shore due to curiosity, or for collecting fish from the exposed seabed.
aakash with a high risk of tsunami may use tsunami warning systems to detect tsunami and warn the general population before the wave reaches land. In some communities on the west coast of the United States, which is prone to Pacific Ocean tsunami, warning signs advise people where to run in the event of an incoming tsunami. Computer models can roughly predict tsunami arrival and impact based on information about the event that triggered it and the shape of the seafloor (bathymetry) and coastal land (topography). [3]
One of the early warnings comes from nearby animals. Many animals sense danger and flee to higher ground before the water arrives. The Lisbon quake is the first documented case of such a phenomenon in Europe. The phenomenon was also noted in Sri Lanka in the 2004 Indian Ocean earthquake. [4] Some scientists speculate that animals may have an ability to sense subsonic Rayleigh waves from an earthquake minutes or hours before a tsunami strikes shore (Kenneally, [5]). More likely, though, is that the certain large animals (e.g., elephants) heard the sounds of the tsunami as it approached the coast. The elephants reactions were to go in the direction opposite of the noise, and thus go inland. Humans, on the other hand, head down to the shore to investigate.
While it is not possible to prevent a tsunami, in some particularly tsunami-prone countries some measures have been taken to reduce the damage caused on shore. Japan has implemented an extensive programme of building tsunami walls of up to 4.5 m (13.5 ft) high in front of populated coastal areas. Other localities have built floodgates and channels to redirect the water from incoming tsunami. However, their effectiveness has been questioned, as tsunami are often higher than the barriers. For instance, the tsunami which struck the island of Hokkaidō on July 12, 1993 created waves as much as 30 m (100 ft) tall - as high as a 10-story building. The port town of Aonae was completely surrounded by a tsunami wall, but the waves washed right over the wall and destroyed all the wood-framed structures in the area. The wall may have succeeded in slowing down and moderating the height of the tsunami, but it did not prevent major destruction and loss of life.
The effects of a tsunami can be mitigated by natural factors such as tree cover on the shoreline. Some locations in the path of the 2004 Indian Ocean tsunami escaped almost unscathed as a result of the tsunami’s energy being sapped by a belt of trees such as coconut palms and mangroves. In one striking example, the village of Naluvedapathy in India's Tamil Nadu region suffered minimal damage and few deaths as the wave broke up on a forest of 80,244 trees planted along the shoreline in 2002 in a bid to enter the Guinness Book of Records. [6] Environmentalists have suggested tree planting along stretches of seacoast which are prone to tsunami risks. While it would take some years for the trees to grow to a useful size, such plantations could offer a much cheaper and longer-lasting means of tsunami mitigation than the costly and environmentally destructive method of erecting artificial barriers.
