car computation seminar report doc

8/18/2019 car computation seminar report doc

1/19

Seminar Report 2006-2007Car to Car Communication

1. INTRODUCTION

For intelligent transport systems, car communication systems, of which car navigation is

a typical example, are demanded to process advanced multimedia information and

communication functions for implementing various information services, such as providing

traffic information by means of the VICS (vehicle information and communication system)

service, providing tips about points of interests by means of Internet communication, distributing

music and video data by means of digital broadcasting, emergency call service, and !C

(electronic toll collection) service" In response to those demands for I!S car information

systems, #itachi, $td" has ta%en up the challenge of developing, in addition to car

communication technology, technology for cooperation between car navigation and multimedia

communication systems via Internet, technology for highly reliable car communication,

technology for highly&reliable electronic toll collection on&board e'uipment () in a vehicleenvironment, and human interface technology for in&vehicle use, such as voice recognition

technology with excellent noise tolerance characteristics that enables use in noisy vehicles, etc"

Department of Applied Electronics ModelPolytechnic Mattakkara

*


2/19


2. COMPLETE SYSTEM

ARCHIETECTURE

+ car communication system is an information processing system that is installed in a

vehicle for providing various types of information services to the driver through the exchange of information between systems inside and outside the vehicle via telecommunication and

broadcasting" !he car navigation system, which is representative of these systems, calculates the

vehicles location using -S (global positioning system) and displays that location onto

electronic maps, and guides the driver to the destination" +lso, the VICS (vehicle information

and communication system) service for providing traffic information by means of

telecommunication or broadcasting has been developed to a practical stage and is being

introduced into car navigation systems"


.


3/19


Fig.1.Complete ca comm!"icatio" #$#tem

!his system, which allows charging of highway tolls by communication between the toll

collection facility and the vehicle, is also expected to come into wide use" In future, we believe

that this system will develop toward a car communication system for the advanced processing of

information from inside and outside the vehicle, such as multimedia communication processing

functions for receiving points of interest information through communication with the Internet

and other such open systems outside the vehicle, downloading and doing the playbac% of music

and video data through high&speed data communication and digital broadcasting and vehicle

control cooperation processing functions for informing the driver of vehicle conditions and

ma%ing the emergency call automatically in cooperation with vehicle control systems, and so on"

#ere, we describe a basic configuration of the car communication system and its %ey

component of a highly&reliable car communication system that achieves compatibility of

multimedia communication processing, which re'uires open connectivity, and vehicle control

cooperation processing, which re'uires high reliability" /e also describe the !C terminal,

which has been one of the hot topics, and voice recognition technology that features excellenttolerance of noise, which is expected to serve as a means of comfortable system operation in the

vehicle car communication is an information processing e'uipment that is installed in a vehicle

and serves as a %ey component of the complete system" It consists of a C-0, a display and other

user interface devices, and has communication interfaces with other in&vehicle devices" !his car

communication is implemented at low cost as a single 12 bit -ower 3ac processor that has both

the open connectivity capability and the highly reliable real&time processing capability"

%. THE CAR COMMUNICATION

INTERFACES

!he basic interfacing of the I!S car communicating system and its car communication

are shown in Fig" ." !he car communication is an information processing e'uipment that is

installed in a vehicle and serves as a %ey component of the I!S car information system" It


4


4/19


consists of a C-0, a display and other user interface devices, and has communication interfaces

with other in&vehicle devices" !his car communication is implemented at low cost as a single

hardware processor that has both the open connectivity capability and the highly reliable real&

time processing capability"

Fig .2. I"te&aci"g o& ca comm!"icatio" #$#tem

%.1. OPEN CONNECTI'ITY AND HI(HLY)RELIA*LE

REAL TIME PROCESSIN( CHARACTERISTICS

!he I!S car communicating system is expected to provide various information services

to the driver via telecommunication and broadcasting channels" !he system is also expected to

inform the driver of the vehicle conditions, the proper guidance in case of an emergency and

roadside conditions in co&operation with in&vehicle control units" + car communication that is

e'uipped with many user interface functions, such as a display, is expected to play a central role

in that processing" !hus, the car communication must have the open connectivity needed for

open information provision services that allow rapid development of service content" !o provide

car navigation services and services that involve cooperation with other on&board devices such as

electronic control units, on the other hand, highly reliable real&time processing characteristics are


2


5/19


re'uired" !hat is to say, the car communication must offer both open connectivity and highly

reliable real&time processing characteristics at the same time"

In order to achieve open connectivity, a software download function for implementing

new services that are offered by information service centers is re'uired" #owever, the 'uality of

downloaded software and the correct processing of it by the car communication cannot be

verified at the time the car communication leaves the factory" +ccordingly, open connectivity

and highly reliable real&time processing characteristics can be said to be mutually opposing

issues" 5ual Ss Computer ne solution to the problems outlined above that can be considered

is to implement the car communication as two computers, one for implementing open

connectivity and the other for implementing highly reliable real&time processing" !hat approach,

however, increases system si6e and cost and involves many other problems, such as the sharing

of the display and other user interface devices"

/e therefore attempted to solve this problem by applying the 5+73+ software

technology*) of #itachi, $td" to the car communication, allowing two different Ss to run on a

single C-0 at the same time" !his car communication employs the 5+73+ technology to allow

an open S and high&reliability real&time S to run on the same hardware at the same time" In

that way, the open services provided by information service center can run under the open S

and car navigation and cooperative services with electronic control units that re'uire highly

reliable real&time processing characteristics can run under the high reliability real&time S (Fig"

.)" /ith the 5+73+ technology, the high&reliability S continues to operate and provide its

functions even if the open S free6es up for any reason" In this way, it is possible to implement a

compact and low&cost car computer that simultaneously satisfies the conditions of open

connectivity and highly reliable real&time processing" !he screen image of the I!S car

information system presented on page *8. shows the display of a prototype car communication

that was developed with 5+73+ technology in which 3- (3oving -icture xperts roup)

&2 video data is being presented via the open S while car navigation functions are being run on

the high&reliability real&time S side .)"

%.2. ETC ON)*OARD E+UIPMENT

!he !C on&board e'uipment () is expected to come into truly practical use in the

year .881" !he !C consists of a main unit that is installed in the vehicle and an IC card"


9


6/19


!he accomplishes cashless toll collection by conducting wireless communication with

roadside e'uipment (7S)" !he IC card that is inserted into the stores transaction

settlement information" Considering use within a vehicle, a car mounted device that is small,

easily installed, and easy to operate, as shown in Fig" 4, has been reali6ed" In addition, high

reliability operation in the car&mounted environment has been maintained" !he configuration of

the !C is shown in Fig" 4 (b)" ach component of the is described below"

,1- RADIO UNIT

!his component conducts communication with 7S by receiving 9": #6 radio signals,

demodulating them, and then sending the resulting digital signal to the communication controller

and by modulating the digital signal sent from the communication controller to a 9": #6 radio

signal and then transmitting that signal"

,2- COMMUNICATION CONTROLLER

!his unit provides lin% connection control, such as establishing and releasing lin%s with

7S, error control, and encoding and decoding abstract syntax code, etc"

,%- ETC PROCESSOR

!his unit performs !C application communication with 7S and #3I control, such as

charge notification output to a li'uid crystal display, etc"

,- SECURITY UNIT

!his component performs authentication by means of two&way communication with

7S using a specified authentication method"

,/- TEST FUNCTION UNIT

!his component performs connection testing according to inter&connectivity technologystandards for the purpose of guaranteeing the inter&connectivity of the wireless communication


1


7/19


functions" !he functions described above are used by the !C to implement cashless toll

collection by means of radio communication with 7S without stopping the vehicle"

. 'OICE RECO(NITION

Considering that more and more diverse automobile&oriented services will be offered, the

'uestion of how to implement a human&machine interface that is safe and easy to use in the

limited space inside an automobile while driving is an important issue" Voice recognition

technology holds promise as an in&vehicle #3I technology for that purpose" In the following

sections, we describe the expectations for voice recognition technology, voice recognition

principles, and the special features of speech recognition middleware products for

microprocessors" Voice recognition is an essential support technology for the human interface,

which serves as interfaces between human and machine" For the interior of a vehicle, in

particular, there are high expectations for voice recognition from the viewpoints of operability

and safety" !he understanding of naturally spo%en words is the ultimate goal of voice recognition

research" !he current practical state of the art, however, is recognition of a limited set of words"

.1. 'OICE RECO(NITION STA(ES

,1- 'OICE INPUT UNIT.

!he component performs the processing for converting the input analog speech signal to

a digital signal"

,2- SPEECH ANALY0ER.

!his component performs the processing for analy6ing the speech waveform to convert

the input to parameters that represent the speech features" !he speech analysis is basically a

matter of obtaining speech spectrum information" In short intervals of from *8 to .8 ms (frames),

the speech waveform is analy6ed and a series of speech parameters that represent the speech

spectrum is obtained"

,%- SPEECH DETECTOR.


;


8/19


!his component detects speech segments in the input speech" +dvanced technology is

re'uired for accurate speech segment detection in the presence of motor noise"

,- COMPARISON UNIT.

!his component compares the input speech with word models by calculating the degree

of similarity of the two expressed as a probability" !hat comparison is based on a lexicon of

word models that have been constructed as lin%ed phonemes on the basis of an acoustic model in

which the features of the basic sound units of speech, such as phonemes and syllables, are stored

in advance"

NA'I(ATION PROCEDURE

Car navigation systems guide a car driver through a complicated route

in road networ%s, while displaying geographical information along the

route" !oday, commercially available car navigation systems can provide

a 45 perspective view of a road networ% as well as its corresponding bird


9/19

Seminar Report 2006-2007Car to Car Communicationferred to as nonperspective projection" 3odeling such nonperspective

pro=ection is an important issue in computer graphics in general, because

it enriches the use of .5 pro=ections, the common visual mediafor conveying information about 45 scenes"

/hile a relatively small amount of wor% has been done on this sub=ect,

recent study has made progress in the techni'ues for distorting

perspective pro=ections" In particular, the latest methods have extendedthe expressive power of such pro=ections > not by distorting .5 perspectives

or bending sight rays directly > but by deforming the target45 ob=ects instead" #owever, these methods limit the degrees of freedom

in the deformation of the target ob=ects because they re'uire us to

design the associated distortion in .5 pro=ection indirectly by deforming

their 45 shapes" !his leads to a tedious trial&and&error process"

3oreover, animating such pro=ections with temporal coherence introduces

further difficulties to the methods"!his paper presents a method of animating nonperspective pro=ections"

!he application is a new type of car navigation system in which

a driving route remains visible without being occluded by surrounding

mountains and valleys" !he technical contribution of this paper

lies in formulating the nonperspective animation as an inverse problem

of finding a deformed 45 terrain surface from the .5 screen arrangementof its associated geographical landmar%s" Furthermore, the

present approach fully augments the visual realism of a 45 scene in

the locally distorted pro=ection by assigning appropriate textures and

shading effects on the terrain surface" !he method thus offers a perceptually

reasonable compromise between the perfect perspective andvisual clarity in the .5 pro=ection" Figure *(b) displays such an example

in which the route around the current position is more visible using

our nonperspective approach"

Conventional non&perspective pro=ections are assumed to include

rectangular ob=ects such as buildings, which help us perceive partial

perspective in the scenes" #owever, in that case, we can assign a differentviewpoint to each rectangular ob=ect, and then camouflage the

associated inconsistency between their perspectives on the flat ground"

7efer to ?*@ for an example" n the other hand, this study rather pursues

seamless change in perspective over the .5 pro=ection, and thusfocuses on depicting smooth terrain undulations such as mountain and

valleys, rather than city areas with rectangular buildings" Several routenavigations in mountain areas are also conducted to demonstrate the

effectiveness of the present approach"

Animation snapshots in navigating the Takeshi village, Nagano, with (a) ordinary perspective projection and (b) temporary coherentnonperspectiveprojection. The route (in red) is occluded by a mountain on the right in (a) while it is visible in (b).


A


10/19


Fig. . An e!ample o" a commercially available car navigation system. A #$ perspective view o" a road network (le"t) and its corresponding

bird%s&eye&view (right).

2 RELATED WORKCompared with photorealistic representations that pursue the physical

realism of optical properties, nonphotorealistic representations have

been studied rather by ta%ing account of human visual perception and

understanding" !hese representations give rise to a new approachcalled nonphotorealistic rendering (NPR) ?1, *:@" #owever, most nonphotorealistic

representations are limited to the rendering stage in the

graphics pipeline, and a relatively small number of such representations

have been applied to the pro=ection stage"

/hile several .5 image&based methods have been proposed to warp

ordinary perspective images, their ability to incorporate different viewpointsis limited" Seit6 et al" ?*9@ introduced a method called view

morphing , which simulates the motion of a virtual camera to interpolate

between photographs ta%en from different viewpoints" Borin et

al" ?.2@ presented approaches for correcting distortions that may exist

in ordinary perspective images such as photographs and pictures"

/e can also enrich the expressive power of perspective images bymodifying the pro=ection mechanism" Multiperspective panoramas by

/ood et al" ?.4@ allow us to merge local perspective images seamlessly

along a camera path for creating bac%ground images for cel

animation" +lthough this is the first to address multiple viewpoints

assigned to local features, it still cannot preserve the smoothness of a

45 scene everywhere in the final .5 images" +grawala et al" ?*@ presenteda method called artistic multiprojection rendering , where each

45 ob=ect is rendered as seen from its own vista point individually"

onetheless, the method is not suitable for our purpose because the

45 ob=ects must be disconnected"ending sight rays with various types of lenses enables magnification

of the specific features in the .5 pro=ection ?**@" ier et al" ?.@


*8


11/19

Seminar Report 2006-2007Car to Car Communicationintroduced a see&through interface e'uipped with a magnification lens

paradigm called magic lenses" Such magnification effects are very

useful especially when we want to highlight some specific features inthe context of information visuali6ation ?;, *1@" For volume rendering,

on the other hand, Cignoni et al" ?4@ introduced the magicsphere

paradigm that can apply different visuali6ation modalities to the target

datasets, and Dur6ion et al" ?:@ simulated 45 ob=ect deformations by bending the sight rays together with hardware&assisted 45 texturing"

3oreover, $a3ar et al" ?A@ and /ang et al" ?.*@ refined the effectsof such magnification lenses and accelerated the associated computation

with the help of contemporary hardware environments" #owever,

these approaches aim at simulating rather optimal properties of magnification

lenses, and thus have relatively little freedom in distorting

.5 perspectives"

7ecently, several models have been presented that distort .5 pro=ections by deforming the associated 45 ob=ects" 7ademacher ?*2@

introduced a concept of view-dependent geometry that encodes view

dependency during the phase of 45 ob=ect modeling, which leads to

several recent methods for controlling 45 shapes according to the camera

position" 3artin et al" ?*4@ proposed observer dependent deformations,

utili6ing user&defined non&linear functions relating the transformationof a 45 ob=ect with its orientation and distance from the

camera" Singh et al" ?*;@ presented a fresh perspective approach to

generate the mixture of perspective, parallel, and other pro=ections

by attaching camera constraints that impose perspective locally in .5

pro=ection" !his has been extended to a framewor% called RYN ?2@,which accommodates temporary coherent animations" !hey have also

developed an interactive interface that directly manipulates the .5 positions

of features on the screen for designing nonperspective pro=ec&

'esolving occlusions with geographical landmarks (a) the routeoccluded by the mountain, and (b) the route that avoids the mountain.

tions ?9@" !heir framewor%, however, aims at rather artistic representation

of the target scene, and assumes that the .5 positions of feature

constraints are provided manually by users" !a%ahashi et al" ?*A@ introduceda model of surperspective projection to simulate hand&drawn

illustrations such as mountain guide maps" /hile the method accomplishes

more freedom in the deformation of the target ob=ect, it is still

limited to static images and cannot provide enough degrees of freedom

for our purpose because it tries to find optimal arrangements of a small number of clustered mountain and valley regions in the scene,rather than local characteristic landmar%s such as mountain s%ylines


**


12/19

Seminar Report 2006-2007Car to Car Communicationand driving routes"

3.1 Fundamental settings in the systemur car navigation system stores elevation data on a regular grid at 98

meter intervals together with road networ%s in the database" !he terrain

surface on a grid is triangulated in advance to create a mesh representation"!he system then searches for the shortest route between the

given starting and end point" ext, the system simulates a drive on the

route around the current position by animating nonperspective views

of the real terrain surface from a car window"

In our implementation, the tilt angle of the camera is set to 48 degrees

and the distance of the camera from the current car position isfixed to be constant" /hile the tilt angle can usually range from .8 to

;8 degrees in commercially available navigation systems, the 48 degrees

was chosen in this paper because it is the best to show the effects

of occlusion elimination in the system" +s shown in Figure *, the current

position is represented by a green wedge&li%e ob=ect and the route

of interest is represented by red thic% linesE other roads are painted ingray" !he car position is fixed at the lower center of the .5 screen so

that the forthcoming route can be viewed as clearly as possible in theupper part of the screen, while the previous positions are also trac%ed

as light blue points" See also navigational snapshots of the system in

Figures ** and *."3.2 Calculating animated fames!he overall process of calculating animated frames in the navigation

system consists of the following four steps

*" xtracting geographical landmar%s such as mountain tops and

road features (Section 2)"

." Calculating an optimal arrangement of the geographical landmar%s

on the .5 screen (Section 9)"4" 5eforming the 45 terrain surface so that it satisfies the precomputed

arrangement of the landmar%s (Section 1)"

2" +nimating the resulting nonperspective image by retaining its

temporal coherence (Section ;)"ach step will be described in Sections 2 to ;, respectively"

eographical landmarks (a) terrain landmarks and (b) roadlandmarks.


*.


13/19


E!TRACT"#$ $EO$RA%&"CAL LA#D'ARK(!his section describes a method of extracting geographical landmar%sfrom terrain surfaces and road networ%s" !he geographical landmar%s

indicate positions on which .5 screen constraints are imposed, in order

to deform the target 45 terrain surface later"

).1 Classificati*n *f ge*ga+hical landma,sSince the aim of distorting perspective images is to avoid occlusions

of driving routes, geographical landmar%s should be extracted from regionsthat may cause such route occlusions" For example, Figure 4(a)

shows an ordinary perspective image in which a mountain hides a road"

!his implies that once we can extract geographical landmar%s such as

mountain s%ylines and road segments, we can resolve the route occlusion

by changing the relative positions of these landmar%s together

with an appropriate deformation of the terrain surface, as shown inFigure 4(b)"

In our approach, we classify the geographical landmar%s into two

groups terrain landmar%s and road landmar%s" !he following two

subsections describe how to extract these two types of landmar%s").2 Teain landma,s!errain landmar"s are defined as points on the silhouettes of mountains

and valleys" !he silhouettes correspond to border edges betweenvisible and invisible faces in the triangulated terrain surface ?*.@, and

may cause the occlusion of driving routes"

/hile such silhouette edges are necessary to resolve the route occlusion

problems, they still cause some problems in retaining temporal

coherence in animation because they are view&dependent features"

!his suggests the idea that edges on the triangulated terrain surface

should be extracted if they are on the silhouettes when seen from oneof all possible viewpoints, so that we can trac% the landmar%s consistently

with any viewpoints" In practice, we sample viewpoints on the

viewing hemisphere that covers the terrain surface, in order to detect

such terrain landmar%s when seen from each viewpoint sample as a

preprocessing step as shown in Figure 2(a)" /e then store the resultsin the system so that we can retrieve the extracted terrain landmar%s

immediately" ote that we apply a aussian&li%e filter ?.8@ in this preprocessing

step for finding globally smooth silhouette lines when pro=ecting

the terrain surface from viewpoint samples" Figure 9(a) shows

terrain landmar%s (in green) extracted in our system").3 R*ad landma,s+s shown in Figure 2(b), road landmar"s are defined as points of extrema

in curvature and inflection points where the signs of curvatures

change on the road, as well as its dead ends and =unction points" 3oreover,the method also extracts the connectivity of the road landmar%s

as edges to %eep the topology of the original road networ%s" !his is because

distortion around sharp curves on the road as well as the changein road connectivity can be easily perceived by the human eye" Since

these landmar%s are inherently view&independent features, they can

also be extracted beforehand along with their networ% connectivity in

the system" Figure 9(b) exhibits road landmar%s (in blue) extracted in

the system"


*4


14/19


*andmarks e!tracted "rom the terrain sur"ace and road networks(a) terrain landmarks (in green) and (b) road landmarks (in blue).

).) Resticting the aea f* landma, e-tacti*nSince our attention is limited to the neighborhood of the current car position,

the system retrieves terrain landmar%s only for local terrain areawithin the view frustum and some specified radius of the current position"

#ere, we consider the view frustum of the double&si6ed screen to

cope with drastic changes of view orientations along the driving route"

+s for the road landmar%s, attention is further restricted to landmar%son the driving route of interest" #owever, in this case, landmar%s on

other roads around the =unction points of the route were also collected

in order to maintain the original road shapes in the vicinity of the route

for later navigation phases" Figure 9(b) shows that this method also extracts

road landmar%s on other road (in gray) in addition to those on

the route (in red), around the =unction point at the center of the screen" O%T"'"/"#$ 2D ARRA#$E'E#T OF LA#D'ARK(!he extracted landmar%s serve as point&position constraints in deforming

the 45 terrain surface to generate nonperspective pro=ections"

#owever, in the present approach, we calculate the 45 positions of thelandmar%s not directly, but indirectly by first calculating the optimal

arrangement of the landmar%s on the .5 screen and then finding the associateddeformation of the terrain surface" !his strategy is our ma=or

technical contribution because it can fully respect the .5 arrangement

of geographical landmar%s and thus ma%es it possible to exclude unexpected

occlusion of the driving route while smoothly interpolating the

associated perspective over the .5 screen" !his section describes an

algorithm for automatically finding such optimal arrangement of theextracted landmar%s


*2


15/19


16/19


1. GPS NAVIGATION

Setting up -S avigation is easy" 0se armin or any -S receiver with 0S interfaceyou can set up a -S avigation system in your car" For -S software, there are many that may

suit your re'uirement"

2. MUSIC

/ith your car communication, you can listen to any type of digital music format" utput

from our Car Front 0nit is a 4"9mm stereo =ac% which is compatible with many auto C5 player

in your car" r you may use a F3 transmitter to do without wiring &turn on your car radio and

tune to a particular channel to receive from the F3 transmitter"

3. MOVIE

/ith your car communication, you can watch any type of digital movie format" 3ovie

files can be stored onto hard dis% so you can have .8&28 movies on your computer ready to play"

4. INTERNET

ur car communication is built&in with luetooth" !hat mean you may use any luetooth

compatible cellular phone to connect to the Internet while on the move" ever lose an important

email or chec%ing on the stoc% mar%et is as easy as in your office" roadband /i&Fi access is

also popular in many places" -ar% your car near a #otspot and you can browse the Internet at full

speed"

5. PHOTOALBUM

!ravelers are having hard time when their digital camera run out of memory card space"

ever worryE with car communication you can download all the photo files to its hard dis%" Save

your memory card for more photos" -lug in C5"

6. OFFICE


*1


17/19


/hen you have your laptop with you" Gou can synchroni6e files and emails with your car

computer"

. SATELLITE RADIO

-lug in a satellite radio receiverE you can immediate access hundreds of radio channel no

matter where you are on earth"

8. DIGITAL TV BROADCAST

5igital !V is becoming popular in urope and 0S+" #aving installed a 5igital !Vreceiver (0S type) you can watch news programs and your favour episode in car"

3. ENTERTAINMENT

Computer games are popular for younger ages" Children can play computer games in car

for entertainment"

. CONCLUSION

+mong the technologies related to the I!S car communication system, for which iverse

information services for automobiles are expected to be developed in future, we have described

the basic configuration and a car communication, the !C , which is expected to come into

actual practical use in .881, and voice recognition technology, which hold promise as a human&

machine interface in the limited operating environment of a vehicle interior" In future wor%, we

intend to proceed with the development of devices that are even more useful and highly reliable

for the field of information services for automobiles, which are expected to continue to advance


*;


18/19


4. REFERENCE.

(*) Saitoh et al", H5evelopment of the 5+73+ 5ual Ss xecution nvironment, 9Ath

ational Conference of the Information -rocessing Society of Japan, 2&4 (Sept" .88*)"

(.) %ude et al", H+ Study of the ext&generation Car -latform, 7esearch 7eport of the

+dvanced #ighway !raffic System 7esearch roup of the Information -rocessing Society of

Japan, AA, I!S&2 (3ar" .882)"


*:


19/19


(4) #orie et al", HSecurity System for Supporting the !C (lectronic !oll Collection)

System, #itachi #yoron 42, .*A&... (3ar" .882) in Japanese"

(2) #atao%a et al", HVoice 3iddleware for the Super# 3icroprocessor, #itachi #yoron

45, 9.;&94. (3ar" .88*) in Japanese"

6E*SITES

(9) www"hitachiautoc"com"

(1) www"howstufwor%sKel"com

(;) www"darmadualKcar"com


*A
http://www.hitachiautoc.com/http://www.howstufworks/el.comhttp://www.darmadual/car.comhttp://www.hitachiautoc.com/http://www.howstufworks/el.comhttp://www.darmadual/car.com

car computation seminar report doc

Documents

Transcript of car computation seminar report doc