DEVELOPMENT OF PRACTICAL SCENARIO SIMULATORFOR DISSEMINATION OF DISASTER INFORMATION
Toshitaka KATADA1), Junsaku ASADA2)，Noriyuki KUWASAWA 3) and Yasushi OIKAWA3)
Abstract: Until now, for studying the efficiency of dissemination of disaster information, we have beendeveloping the simulation model. Based on the simulation model, we built the general-purpose systemthat has made it possible for users to efficiently study dissemination of disaster information the processused, and the scenario for transmitting information. This simulation system makes it possible to express
the situation in which information is transmitted using various media. This system uses GUI to simplify
operations for general users. And updating and adding new features to this system is very easy.
Keywords：Dissemination of disaster information，Support of disaster prevention plan,
Scenario Simulator，The research planning support system，Object Oriented

1. INTRODUCTION
At the time of a disaster originating, from theviewpoint of minimization of death and injury, it is very
important to transmit disaster information such as anevacuation order, promptly and efficiently to residents. In
order to transmit information promptly and efficiently
before the disaster occurs, these points become important;performing decision making of information transfer
quickly by collecting information quickly and transmitting
information during an organization, efficiently, andperforming information transfer quickly and correctly to
all residents by sending disaster information in a timely
fashion. That is, in order to satisfy these criteria, it isnecessary to fulfill the three requirements of thecompleteness, speed and the accuracy of the transfer ofdisaster information, by fixing organization for the
information transfer at the time of a disaster.
With regard to the problem of the increase in efficiency
of organization of the information transfer at the time of adisaster, Monma et al.(1997), Shiiba et al.(1998), etc.
explore the method of examination by the simulation. In
these studies emphasis is put on parallel correspondence
between disaster-prevention organizations, the decisionmaking in a disaster-prevention organization and theinformation transfer between organizations. In these studies,
the examination of the process of information transfer
between an organization and residents and the process of
the information transfer between residents is insufficient.
However, if based on the assumption that the final purposeof transmitting disaster information is to guide suitableaction of the residents who receive that information, it will
become evident that the importance of examination of theprocess, by which disaster information is acquired, is great.
From this point of view, we gained an understandingof information transfer action of the residents at the timeof a disaster by investigation, and studied the method of
evaluating the efficiency of information transfer bymodeling it. In the study, we examined the following
matters; Firstly how to express information transfer
action of residents as a simulation model reflecting theproperty of information transfer action of the residents as
it changes with damage grades. Secondly, how to build
disaster prevention administration radio systems into amodel. Thirdly, basic technology, which is based on theabove, and carries out the simulation of the informationtransfer to residents on a computer.
Then in this study, we developed a simulation
system that expresses the information transfer ofresidents and information transfer performed by various
media based on the knowledge obtained from thestudies so far. The system developed by this research
has the following features. It is processes developmentof various situations, which change in real time, and it
makes it possible to summarize the situation of
information acquisition and the operational situation of
the information transfer media as it changes moment tomoment. Secondly, it is structured such that functional
extension by adding other transfer media can be
performed easily. Thirdly, by giving an operation

1) Regular Member of JSCE, Dr.Eng., Associate Professor, Gunma University,(1-5-1 Tenjin-tyo Kiryu 376-8515 JAPAN)
2) Regular Member of JSCE, Graduate School of Engineering, Gunma University,(1-5-1 Tenjin-tyo Kiryu 376-8515 JAPAN)
3) Student Member of JSCE, Graduate School of Engineering, Gunma University,(1-5-1 Tenjin-tyo Kiryu 376-8515 JAPAN)

function equivalent to general computer software, thecommon user who does not have specific knowledge ofthe system is able to perform a simulation easily.
Since the disaster information transfer simulation
system developed by this study has the above functions,
it can be used in a wide variety of situations as a scenario
simulator for performing examination of the maintenanceplan of information transfer media. Such as thearrangement plan of a disaster-prevention administration
radio system, the official-announcement timing of theevacuation order in response with the development of adisaster scenario and so on.
2. DISASTER INFORMATION TRANSFERSIMULATION MODEL
2.1 The Outline of the Simulation Model

This model has the following features.
1. The information transfer in realistic space isreproduced by arranging an individual's position to an
x-y-z coordinate system.
2. Since the properties of various transfer media (such as
the information transfer action of an individual anddisaster prevention administration radio) are incorporated
as parameters it is possible to set up various scenarios
about the function of media by operating these parameters.
3. It is possible to set up the scenario about thegenerating time of a disaster the dispatch timing ofdisaster information, etc. by having improved the model
which we developed until now, as a system in which time
control is possible.
2.2 Information Transfer among Residents

Modeling of the information transfer among residents
involves modeling of the oral communication and theinformation transfer by telephone among residents. The
oral communication among residents is expressed bymodeling the process of oral communication of theinformation starting from the arbitrary residents who
acquired information by a certain means as a network
generating process. Basic structure of the simulation
model is constituted according to Biased Net Model,
which is the human network formation theory inmathematical sociology. Biased Net Model is theprobability-theory-network generation model developedby imitating the information transfer structure of a nerve
cell. Biased Net Model is applied to the research for afriend selection problem by Fararo,T.J.(1981),

Skvoretz,J.(1985), etc. in social science.
Fundamentally, the network of the informationtransfer among the residents in this model is expressedby the random selection of partner expressed in theposition by x-y-z coordinate system. On the basis of thisnetwork, the process of the information transfer among
the residents reflecting the grades of damage is expressedby operating the parameter expressing the property of
information transfer action of the residents who changewith the grades of damage. In this study, the property oforal communication of residents is caught from three
viewpoints (the number of partners per informationtransfer, the distance to the partner for informationtransfer, and the relation of selection between theresidents with some biases). The time property for oral
communication of residents is expressed from two
viewpoints; the time of the standby required by thetransmission action, and the time required to transfer. In
order to express the above viewpoints in a simulation
model, the following parameters are defined.
(1) The parameters expressing the property of oral
communication of residentsa) The number of partners for information transfer
This parameter signifies number chosen as a partner
for information transfer of one household. A distributionof the value of this parameter is based on a distribution of
the number of partners for information transfer found byinvestigation conducted in the object area of a simulation.
b) The distance to the partner for information transfer
This parameter signifies a distribution of the distanceto partner for information transfer that the householdchose. A distribution of the value of this parameter isbased on a distribution of the distance to partner for
information transfer grasped by investigation that
conducted in the object area of a simulation. By
introducing this parameter into a model, we can grasp
influences of the spatial spread of the area and therelation of the position of the residents on a spread of the
network of information transmission among residents.
c) The relation of selection between the residents
This parameter signifies probability that bias occurs
at the time of choosing the partner for informationtransfer between residents. Generally if a selection oftransfer partners was not performed at random, between
some persons who were chosen by the same partner, it
can be considered that they are biased toward choosing
each other. This parameter expresses the generation
probability of the selection of partner involves such bias.

(2) The parameter expressing the time property of oral
communication.
a) The standby time required by the transmission action
This parameter signifies the time from initialacquisition of information to coming out of a house.
With regard to information transfer action while
performing refuge preparation action of residents, it was
found by investigating whether information transfer
action is performed while performing refuge preparation
action. With regard to information transfer action while
performing refuge action, it is expressed with reference
to the timing of coming out of a house for refuge.
A distribution of the value of this parameter is foundby investigation conducted in the object area of asimulation, too.
b) The time required to transfer
This parameter signifies the time required fromcoming out of a house to the timing of transmission. A
walking speed and a distance to partner for informationtransmission are used to calculate the distribution of thevalue of this parameter. Transfer action using telephone
is modeled by a similar method to that used in modelingof oral communication. Although it is not necessary totake into consideration the distance to the partner for
information transfer and the time required to transfer, it
is required to take into consideration the probability of
telephone convergence and a distribution of the timerequired to convergence, because of the properties oftelephone. For these reasons, the model is createdintroducing these parameters expressing these properties.
2.3 Expression of MediaThe situations at the time of an actual disaster are
varied. It is assumed that disaster information istransmitted in varying situations, too, such as thesituation where two or more pieces of information aretransmitted with time lag to residents by two or moremeans of communication. For this reason, various media
for disaster information, which function simultaneouslywith an information transfer among residents at the timeof a disaster, can be included in this model. So, it ispossible to evaluate the efficiency of the informationtransfer attained by their cooperation in this model.
The media in this model are included in theformation process of a network and are expressed so thatthe property of each medium may be reflected. For
example, the property of the outdoors loudspeaker (while
it has advantage that the information from thedisaster-prevention organization of an area can be
simultaneously transmitted to many surrounding
residents) is problematic in that the probability that it canbe heard tends to be influenced by the weather. In thismodel, in order to express such a property of transfer, theparameter "the range of voice attainment" which means
the range with in which the resident can hear an outdoors
loudspeaker and the parameter "the rate of listening"which means the rate by which households can actuallyobtain information from an outdoors loudspeaker in thearea. With regard to the time which transfer takes, thetiming of an outdoors loudspeaker running is given basedon the set scenario. A transmission of the information by
the outdoors loudspeaker that starts from that time isadded to a network.
As mentioned above, for the outdoors loudspeaker, it
is possible to set up the scenario of arrangement position,
the range of voice attainment, the rate of listening, andrunning timing. Based on the scenario, the network of
information transfer is performed under the cooperation
with the information transfer among residents and media.
2.4 The valuation basis of the efficiency of

information transmission
In this study, we consider the efficiency of informationtransfer from the three viewpoints completeness, speed,
and the accuracy, and define the following three indicesof the rate of information acquisition, the time of
information acquisition, and the number of transfer steps,
in order to evaluate the efficiency of informationtransmission based on the situation of informationtransfer to the residents expressed.
(1) The rate of information acquisition
This index signifies the rate by which the residents
who have acquired information recount it to all theresidents in the object area of information transfer. It isshown that when spread of information is small that thisvalue is small, and conversely that when spread of
information is large that this value is also large. The
standard deviation of the rate of information acquisition
computed when performing a simulation two or moretimes under the same conditions estimates the stability ofacquisition of information. It is shown that when
information is circulated stably this value is small.
(2) The time of information acquisition
This index signifies the time required for eachresident to acquire information. An average and amaximum of this index are calculated.

(3) The number of transfer steps
This index signifies the number of the transfer
processes required by the time residents acquire
information. This index is posited as a substitute index of
the accuracy of information transfer. Because it can beassumed that the qualitative change of information
depends on the number of times the information istransferred.
3. EXPRESSION BY THE PROGRAM OF A
SIMULATION MODEL
3.1 The Design Object of a Program

We expressed a disaster information transfer
simulation model by programming language with thefollowing objects.
1. This simulation model must express the situation
wherein various information transfer media transmit two
or more information such that the contents differ withtime difference. Therefore by positioning timeprocessing in the nucleus of a program, processing of thetiming in a simulation is expressed succinctly. This timeprocessing has synchronous processing of the timing at
which each medium starts information transfer etc.
2. The program enables the introduction of new
information transfer media into a simulation easily, as
there is room for expansion.
In order to realize the above object, we used theobject-oriented technique in programming. Using thistechnique, in order to express information transfer
media, the program is described for every function,
which media have. And in order to express new
media, the existing media can be used, describing
only a new function. This enabled it to perform an
addition and management of information transfer
media easily. Moreover, the program was built
according to event drive type processing structure.
This processing structure describes every event,which generates a program within a simulation. It
was able to carry out coding of the processing
expressing time briefly by exchange of the message
used as the cause of this event combined with time
progress, and was controlled.
3.2 Program Structure

The class structure of a program is as follows(figure-1 reference). The base class of the best layer isMedia Base Class

Transmitted to thecircumfrence

Laudspeaker

Resident

City Hall

DisasterFigure-1 The class structure

equipped with the procedure used as the receiving
window of the message transmitted between an object
and fundamental data attributes common to informationtransfer media. The media base class, which is in the low
rank and collects the features common to each medium.
The media class which is in the lowest rank andexpresses actual information transfer media. This
program expresses information transfer action of area
residents and the function of information transfer media
by making the object take charge of the process of
exchange of the message of each class object and theevent corresponding to the message.
This program is expressing the situation where "acity office makes an outdoors loudspeaker start
information transfer" and "certain residents tell otherresidents information", by exchange of the demand
message of objects. Moreover, this program is expressing
the situation " When residents get information, determine
to take refuge after five minutes", by the demand
message send to itself.
Furthermore, a program must be expressed (whenthere is time lag after an object transmits a message)
before actually being transmitted. For this reason, thisprogram has introduced the management class, whichtakes charge of the processing of time in a simulation.
This management class has the function of managing an
exchange of the message between objects on the basis of
the time within a simulation. When a certain object
transmits a message to other objects, the object registers
the time lag until it is actually transmitted and atransmitting partner's recognition number transmits themessage to a management class. A management classconfirms whether the message, which must betransmitted at the present time, exists. And when themessage, which should transmit, stops existing, it is time
1 unit forward. A management class advances asimulation by performing the above processing (figure-2
reference).

StartForward timeNo

Does the message whichshould be issued now exist?

Registration of an area

Yes
Establishment of parameters

Issue the message

Yes

Execution of the simulation

Does the message notpublished exist?

No
End

Expression of the result

Figure-3 System Flow

Figure-4 Area Registration Wizard

Figure-2 Management Class Flow

Table-1 Parameters
Items

4. The outline of a system, and structure of the function
4.1 The outline of the system

On the system developed by this research, that thedisaster-prevention person in charge of an area can easily
perform examination of the increase in efficiency of adisseminate of disaster information has set in mind. For
that, consider the following. First, the creation and input
of area data must be able to be performed simply.
Secondly, it must be possible to simply perform a setupof the scenario of a simulation. Finally, there must be an
intelligible display of a simulation result.
In this research, the interface, which supports thegeneral work for performing a simulation, was also
developed. The development of the system is premisedon a user not having the special knowledge about acomputer, so that it might become a user-friendly system.
For example, the display uses the dialog form by the GUI
for a parameter setup of a simulation, the value to set up,
and the output result of a simulation in graphical form.
4.2 Composition of a function

In this system, a series of work, which the simulation
performs regarding the dissemination of disaster
information, is shown in figure-3.
(1) Registration of an area
This involves registering data of the area of theobject of a simulation. In order to do this, "arearegistration wizard" is selected from a menu. After
selection data (area name, explanation of an area, the filename of household coordinates data, the scale ofcoordinates data, and so on), which should be set on eachpage displayed, are input. Since the technology withParameters
Occurrence of random numbers, A sort of random
The sort of random numbers
The characteristic of the information transfer
A characteristic the
The time of preparing evacuation
household
The timing of the information transfer
The distribution of partners for information transfer
Oral communications The distribution of the distance to partner for
information transfer
A walk speed
A distribution of partners for information transfer
The informationtransfer using
The rate of the teｌephone convergencetelephone
The distribution of the telephone convergence time
The range of the voice attainment
The rate of listening
Outdoors loudspeakers The installation place of outdoors speakers
The number of setting up outdoors speakers
Running timing
The audience rating
Television and radio
The broadcast timing
The place
The city hall
The determination timing of their intentions
The place of the generating calamity
The number of generating calamity points
The rate of finding to generate the calamity
The point of thegenerating calamity
The range of being possible to find the calamity
The timing of the generating calamity
The rate of reports
Random numbers

which map data is read has been improving remarkably
in recent years, household coordinates data was madeusing a file different from the system.
(2) Establishment of parameters
A dissemination-of-disaster-information simulation
model can change the characteristic function which
various information transfer media have, and thecharacteristic of action by area residents, by operating aparameter. Moreover, a dissemination of disaster
information simulation model can also perform various
scenario setup by setting up the timing to which eachmedium operates. The parameter, which can be set up, isin this system as displayed in table-1. These parameters
are set up in the first stage as a standard value, whichcalculated from the actual investigation result, and they arefreely changed in wizard form. For example, in theparameter which expresses origination of a calamity on asimulation, there are the number of happening points, arange which can be discovered, discovery probability,
coordinate values which show the position of eachhappening point, happening time, and so on. A setup of
the parameter by the parameter wizard of this system isperformed by inputting a numerical value into a dialog asshown in figure-5. Moreover, specification of places, suchas a happening part, can also be set up by clicking thedisplayed area screen and once set up, it is possible tochange a happening part by dragging the icon of thehappening point currently displayed on the specified map.
Timing of a happening can also be changed by
dragging the happening point icon currently displayed on
the timing window on a screen (figure-6 upper part). The
timing window is an icon showing the starting time of ahappening point or various information transfer media
are arranged on the numerical-value axis showing thelapsed time which made simulation start time zero. These
icons can be moved with a mouse drag, and in
conjunction with this, the operation parameter of eachtransfer media is also changed. Using this window, it ispossible to perform a scenario setup, finding the time
relation of each transfer media visually.
(3) Execution of a simulation
If execution of a simulation is chosen from a menu ora tool bar, the simulation based on the scenario setup is
performed. During execution of a simulation, the scroll
display of the timing window is carried out with time
progress within a simulation. When events, such as
generating of a disaster, occur on a simulation, thecontents of an event are displayed on an event window(figure -6 lower part). Inside a system, by supervising the
motion of each object within a simulation, the householdthat acquired information is recognized, the position of
the household is displayed each time, each index such as
the rate of information acquisition each time, informationacquisition time, and the average and the maximum of
information acquisition steps and maximum, arecalculated in real time, and output display on a screen
and updating are performed. By checking these screen
displays, a user can grasp the effect of informationtransfer media, and the situation inhabitants' informationacquisition by animation.
(4) Expression of the result of a simulation
When a simulation is completed, the value of each
evaluation index of information transfer efficiency will
total automatically and the change with the result display
mode is performed on a system. In the result display
mode, the result which expresses each index of

Figure-5 Establishment of parameters on
Area Registration Wizard

Figure-6 Timing Window and Event Window

information transfer efficiency, such as the final rate of
information acquisition of an area, mean informationacquisition time, and the number of mean informationacquisition steps, is displayed in the result display mode.
On the map of the area currently displayed on thewindow, a distribution of the information acquisition
result of each household classified by introductory notesby color is displayed. And it is possible to display andprint various results, such as the rate change of
information acquisition for every time and the transfer
number of cases by medium. On saving these results, one
can perform easily comparison and examination of thesimulation result obtained from each scenario.
5. The Application Example of a System
As an application example of this system, thischapter examines the effect by having introduced thedisaster-prevention speaker as disaster-prevention
administration radio in the area between Watarase Riverand the Kiryu River in Kiryu city, Gunma pref.
The number of households in this region is 8,260,
and this area was heavily damaged by typhoon Kathleen
in Showa 22 (1947). At present, disaster-preventionspeakers are not installed in this area.
The scenario setup in the application example of thissystem is represented by the following two cases. Case 1:
A disaster-prevention speaker does not exist in an area,
but information transfer is performed only by the oraltransfer between inhabitants. Case 2: When 17 disasterprevention speakers have been arranged in the area (theinstallation points are shown in figure-7). We examine
the introductory effect of a disaster-prevention speakerby comparison of both cases. The difference between
both cases is solely the existence of installation ofdisaster-prevention speakers.
Setup of the scenario common to both cases is as follows.
1. Information transfer media other than disasterprevention speakers do not function.
2. Let the happening point be the levee breach of
Watarase River at the Kathleen typhoon.
Disaster information is sent 1 hour before levee
breach. Other conditions are as shown in table-2 andtable-3 and trial of a simulation is 100 times.
The example of a screen display as a result of asimulation is shown in figure-7 and figure-8 and collectionof a simulation result is shown in table-4. Figure-7 is afigure over which the information acquisition situation ofeach household; in the case of having arranged theTable-2 Establishment of Conditions of the Simulation
Items
Information transfer
among inhabitants

The point of thegenerating calamity

Parameters

The value

The walk speed

80m/min

Using telephonenothing

Bias parameter

0.2

The range of being possible
to find the calamity

300m

The rate of finding to
generate the calamity

50%

The timing of thegenerating calamity

1 hour later

Table-3 Establishment of Conditions of the Outdoors
LoudspeakerItems
The city hallOutdoors loudspeakers

Parameters

The value

The determination timingof their intentions

Immediately after
beginning of thesimulation

The number of setting up

17 points

The range of the voice
attainment

250m

The rate of listening

15%

disaster-prevention speaker-was classified by color, andwas distributed for every acquisition time. Figure-8 shows
the information transfer number of cases for every timezone in the case of not arranging a disaster-prevention
speaker and the rate of information acquisition. Thesefigures display visually the result of table-4 showing thelast result of a simulation numerically, and they examine a

Figure-7 The Example of a Screen Display as a Result of a Simulation (1)can be easily performed with many items, so we consider
that this system is useful also in the business of thedisaster-prevention administration of the region.
6. Conclusion

Figure-8 The Example of a Screen Display as a Result of a
Simulation (2)Table-4 A Numerical Results of a Simulation
Outdoors loudspeakers

nothing

17 points

The average of informationacquisition

71.22%

93.76%The maximum of informationacquisition

14 hours

3hours and
14 minutes

The number of average steps

60.57 step

3.91 step

The number of maximum steps

140.24 step

25.50 step

simulation result as these figures represent time local
information transfer situation and the information transfer
situation one time.
From the result of table-4, when we examine theeffect by having introduced the disaster-prevention
speaker, the following observations can be made.
1. Since the rate of information acquisition is increases
by introduction of a disaster-prevention speaker, and thezone where information is not given decreases, theimprovement in completeness is achieved.
2. Since the maximum information acquisition time is asremarkable as 3 hours and 14 minutes and means
information acquisition time is shortened by 19 minutes,
the speed of transmission improves greatly.
3. Since the number of mean steps and maximum steps
also decrease sharply, the number of repetitions transfer
process of the information which inhabitants acquire
becomes fewer, and it comes to the situation that an
informational accuracy is also easily secured.
These observations make it expedient to be
introduced for this system. So, if examining the
introductory effect of a disaster-prevention speaker, itneeds to be repeated many times using this model in amore realistic scenario.
In these circumstances, this system can perform
evaluation of information transfer organization inadvance from various viewpoints since a scenario setup

The ideal method of the information transfer in theevent of a disaster is an important problem, which
influences the scale of death and injury. Recently, theway that should be of a dissemination of disaster
information argues here and there. Many cases where
correspondence is performed in connection with thedissemination of disaster information, (that is, thedisaster-prevention person in charge of a local
self-governing body performs maintenance of thetransfer media including a disaster-prevention
administration radio system and the prior consultation
with a report organization), are also seen.
The value of the scenario simulator of disseminationof disaster information developed by this research isgreat since it can examine in advance the state of theinformation transfer during a disaster by various scenario
set ups. However, it is considered that disaster
information has a big difference in the situation inconnection with informational transfer since the contents
are different from development and form of a disaster. In
the simulator developed by this research, there is aproblem in that a scenario other than the place of thedisaster cannot be set up.
The subject which should be examined in the futureof this research is improving practicality by making it
operate as a part of GIS, which can be used to deal with adisaster as it progresses.
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