INTER-NOISE 2007
28-31 AUGUST 2007
ISTANBUL, TURKEY

Availability of a newly developed social survey method on noiseusing the Internet and the geographic information system (GIS)a~cJiro Kakua and Takatoshi Yokotab, Seiichiro Nambac,
Seigou Ogatad, and Ichiro Yamadae

Kobayasi Institute of Physical Research, 3-20-41 Higashi-motomachi,
Kokubunji, Tokyo 185-0022, dTraffic Safety and Environment Laboratory 7-4227 Jindaiji-higasicho, Chofu, Tokyo, 182-0012, eAviation Environment ResearchCenter, AEIF, K5 Bldg. 1-6-5 Haneda-Kuhkou, Tokyo, 144-0041

JAPANABSTRACT
The brief overview of a newly developed social survey method and its availability arereported. This research system consists of the web-based questionnaire survey about theannoyance caused by traffic noises and the estimation of the noise exposure level at therespondents’ residences based on the geographic information system (GIS). By using the
web-based replying system, vast amounts of response data can be obtained from extensive
regions with relative ease, which has been difficult to acquire such data for traditional
survey methods. Not only the dose-response relationship but also the population
distribution exposed for different noise levels is possible to estimate by combining thepopulation census data with the GIS. The availability of the newly developed method is
confirmed by comparing the dose-response relationships with those obtained by the
traditional methods.
1 INTRODUCTION

To promote the national noise policy effectively, it is important to understand therelationships between the noise exposure and the residents’ annoyance, so-called doseresponse relationships. Up to now, two social survey methods have been mainly used to makeclear the adverse effect of noise in Japan. One is a face-to-face interview by investigators
who visit every household and the other is an indirect questionnaire survey via mails.
Additionally, the noise exposure levels of respondents have been estimated based on the dataobtained by field measurements. Needless to say, these methods are not sufficient to collect avast survey data from much wider areas.
In this research, assuming the questionnaire survey over the Internet, we have built a new
survey system which consists of the recruitment and the selection of applicants for survey,
the collection of survey results and respondents' location information, the management of thecollected data, and so on. On the other hand, we have built another system to estimate therespondents' noise exposure level from the predicted noise level and respondents' location
information using the GIS database. By building the population census data into this system,
we can easily estimate the population distributions of each sound source corresponding todifferent noise levels as well as the individual respondent's noise exposure level. Though thea

Email address: kaku@kobayasi-riken.or.jp
Email address: t-yokota@kobayasi-riken.or.jp
cEmail address: namba.seiichiro@nifty.com
d
Email address: ogata@ntsel.go.jp
eEmail address: i-yamada@center.aeif.or.jpbsocial survey method has not been completed yet, the systems developed so far are
summarized in this paper.
2 RESEARCH OUTLINEThis research system consists of a questionnaire survey on annoyance through the Internet
and an estimation of noise exposure level using the geographic information system (GIS) asshown in Figure 1.
Noise exposure estimation using GIS

Web-based questionnaire surveyImprovement of GIS databasesfor each traffic noise source

Respondent recruitment• Publishing on Website of• Road: Location and structure data…
• Rail: Location and structure data…
• Airport: Runway location data…

public offices etc.
• Distribution of recruitment

leaflet in restricted district
Collection of respondents’
responses and profiles

Analysis of environment
around noise source• Location information• Population census

data

Noise prediction

Confirmation of the existence ofnoise source near residence• Road: ASJ-RTN Model 2003
• Aircraft: INM Model (ICAO)• Rail: Newly developed• Land-use data…

• Road, railway<100m• Airport<1~10 km

Population distribution
around noise source

prediction modelSound exposure level
Sound exposure level of each
respondent for each noise source• Response data

Dose-response relationshipfor each noise source

Noise exposed population distribution
for each noise source

Figure 1: Research flow of the newly developed social survey method.
2.1 Web-based Questionnaire Survey

When adopting the web-based questionnaire survey to investigate the adverse effect ofnoise on residents, the recruitment of the survey applicants who are actually exposed to somesort of noise, the proper collection/management of the survey results and the confidentialityof respondents’ personal information are the significant issues to be considered.
a. Recruitment of survey applicants

A typical way for recruiting applicants is to post a recruitment guide on the web-sites
hosted by the official agencies such as the Ministry of the Environment and/or local
governments. However, this method may be difficult to pick up the applicants who live in thearea adjacent to a specific noise source such as road traffic or railway. To avoid this issue, wemade up a recruitment leaflet and distributed it only in the area adjacent to the objective noise
source as an insert of a life information journal, whose distribution area is precisely managedin each block number. The leaflet indicates the following:● How to access the dedicated URL● Purpose of the survey, which focuses on the living environment● Consideration for personal information protection● Reward for answer (1,000 yen)
The leaflet also includes an area code which varies depending on the distribution area andis required for answering the survey.
b. Collection of survey responses and respondents’ profiles

Applicants can access to the survey system from a personal computer or a cell phone. By
Keying in the area code provided in the recruitment leaflet, the personal information
protection policy is shown on the survey system. Only applicants who agree with this policy
can answer the survey questionnaire. We made up the questionnaire form based on the“Questionnaire on Living Environment (INCE/J-SSM-03)” which was prepared by INCE/J
under the request from the Ministry of the Environment of Japan [1]. The average time tocomplete the survey form is about 10 minuets.
2.2 Noise Exposure Estimation using GIS

We have built a system that can estimate the sound exposure level of respondents byintegrating both the results of noise prediction and the respondents’ location information on
the GIS database. The following summarizes the system for aircraft noise and conventional
railway noise which were the research targets in 2006.
a. Aircraft noise

The GIS database for airport was improved by incorporating the information on thelocation and the length of runaway, the location of respondent’s residence, the population
distribution obtained from the census data etc. into the database. The INM Ver.6.2 developedby FAA was used for the estimation of the sound exposure level of residents. The flight pathand operational conditions of aircrafts necessary for the calculation were obtained frompublic information and field investigations. In the calculation, a part of aircraft types wassummarized into a typical category, and the takeoff profile was adjusted to the standard
operation pattern provided in Japan. By overlaying the noise contour line on the GIS object,
we finally estimated the sound exposure level of respondents.
b. Conventional railway noise

The GIS database for conventional railway was also improved by incorporating theinformation on the location of railway line, the structure and the height of rail track, thelocation of respondent’s residence, the population distribution along the railway lines within
the area of 100 m both sides using the census data etc. into the database. The noise prediction
was carried out using a calculation formula introduced in 1999 [2] with some modifications.
Train types, number of cars for a train, operation speed, and operation schedule etc. necessary
for the calculation were also obtained from public information, paid data, field investigation,and so on.
In addition, the excess attenuation of noise caused by building cluster was calculated
based on the building parameters, such as average building height, porosity of building
cluster and building density between rail track and residents of respondents, derived from theGIS database.
3 RESULTS
3.1 Web-based Questionnaire Survey

In 2006, we conducted surveys on two international airports and five conventional
railways, collecting 2000 responses in total from the residents around the noise sources.

a. Application rate

The method of accessing the dedicated URL was corrected several times in the process ofproceeding with the survey, and was finally modified to allow applicants to connect to theURL via the Web site of Kobayasi Institute of Physical Research. As a result of thismodification, the rate of application with the recruitment leaflet increased from less than 1 %to 1.8 % on average. The ratio of the applications via PCs and cell phones was about 3 to 1.
Given that much more people must have cell phones than PCs, we speculate that the guard
against the phishing is a cause of the lower application of cell phones.
b. Respondent attribute

Table 1 shows the age distribution of the respondents by sex. The overall ratio of male tofemale is 1 to 2, however, the percentage of male increases with age. Although a large
number of respondents are in their thirties or forties, the distribution is more flat across theage than the interview survey conducted by INCE/J [1], in which 65 % of the respondents
were 50 years of age or older.
Table 1: Gender-segregated age distribution of respondents.

AgeSex
femalemaleTotal

18-2020s

30s

40s

50s

60s

>70

221133223
86309534
160
694

304
172
476

144
100
244

5666
122

1461
76

No
answer
31
1243

Total
1,322
668
1,996

c. Available data

Almost all responses were valid for the survey on the airports. On the other hand, many
responses in the railway noise survey are from the residents outside the target area, which
was within 100m from the railway. As a result, about 32 % of the responses were valid. In thecase of railway and road noise surveys in which the target residential area is limited, it isnecessary to carefully choose the way to distribute the recruitment leaflet, such as posting.
3.2 Sound Exposure Level

The accuracy of noise prediction models is validated by comparing the calculated values
with the measured values.
a. Aircraft noise

We used the field data measured by Civil Aviation Bureau of Japan at the Fukuoka
Airport in 2005 and Osaka Itami Airport in 2003. The measurements include the noise ofairplanes like B747-400 that are currently not in operation. The measured WECPNL, which isa noise index for aircraft noise in Japan, was converted to Lden using the empiricalrelationship ‘Lden=WECPNL-13’. The results of comparison are shown in Table 2. While thecalculated values are smaller at all points, the estimation can be practically used considering
the difference of airplane types between before 2005 and now.
Table 2: Comparison between predicted values and measured values in Lden.

Predicted
Measured

Fukuoka Airport
Point 1
Point 262.7 dB
66.2 dB
64.5 dB
70.0 dB

Point 167.8 dB
68.8 dB

Osaka Itami Airport
Point 2
Point 361.9 dB
56.9 dB
63.2dB
58.3 dB

Point 459.4 dB
63.7 dBb. Conventional railway noise

We conducted field measurements along the JR Chuo Line and the Hankyu Kobe Line.
Three areas were chosen for each line. In each area, the noise of running trains was measured
at six points from which the rail track can be directly seen. Table 3 shows the average andstandard deviation of the difference of sound exposure level between the calculation andmeasurement over all measuring points in each area. Although the trend of larger predictedvalues than measurements is observed, it can be concluded that the calculation method weused is feasible for practical noise prediction.
Table 3: Difference between predicted values and measured values in LAS,max.

Mean value andSD of differenceof LAS,max

Point 1

JR Chuo Line
Point 2
Point 3

Point 11.0 ± 1.3dB

2.7 ± 1.9dB

1.2 ± 1.1dB

1.7 ± 2.0
dB

Hankyu Kobe Line
Point 2
Point 30.8 ± 2.7
dB

-1.6 ± 1.8
dB

3.3 Dose-response Relationships

Figure 2 shows the dose-response relationships for aircraft noise and conventional
railway noise, which are derived by combining the results of both the questionnaire survey
and the noise exposure estimation. The horizontal axis is the LAeq during the daytime (6:00 –22:00), and the vertical axis is the percentage of the responses for “highly annoyed (5/5)” and“annoyed ((4+5)/5).” The clear trend of increase of annoyance with increasing noise level
implies that both the questionnaire survey and the exposure investigation were appropriatelyperformed respectively.

Total number of respondents – Aircraft: 588, conventional railway: 448.
Figure 2 – Annoyance vs. LAeq(Day) for aircraft and conventional railway noise.

Next, in order to verify the availability of the survey method, above dose-response
relationships were compared with those which were obtained by traditional survey methods
such as interviews and mailing. Figure 3 and 4 show the comparison of dose-response
relationships, where the results of social surveys carried out in 1999~2000 and 2002~2003 [3,4] are used as comparison data. It is obvious that the responses via Web-based survey are
more severe than the responses obtained by the traditional survey methods. In particular, thedifferences tend to increase in proportion to the increase of sound exposure level.

However, considering the discrepancies such as time and area of the survey, we cannot
conclude that these differences of responses originate in the difference of survey method. We
intend to examine this difference in more detail by conducting a questionnaire survey basedon a traditional method in the areas where we did the Web-based survey.

Total number of respondents – Web-based: 588, mail-based: 970.
Figure 3: Annoyance vs. Lden for aircraft noise.

Total number of respondents – Web-based: 448, interview-based: 662
Figure 4: Annoyance vs. LAeq(Day) for conventional railway noise.

3.4 Free Opinion of Respondents

In this Web-based questionnaire survey, we received a lot of opinions as a free answer
from respondents. The followings are examples of favorable opinion.
● Favorability of answering by own convenience (↔anxiety of receiving an investigator’svisit)● Simplicity of questionnaire and shortness of response time
● Appropriateness of reward
On the other hand, more following opinions with anxiety and distrust of this Web-based
survey were received.
● Reliability of research agency

● Leakage of private information● Opacity of survey purpose and usage of result

It is needless to say that these factors cause low application rate. Therefore, the futuretask for improving the application ratio includes to eliminate the distrust toward the research
agency and to arrange the environment in which the respondents can access to the survey
Web-site without anxiety.
4 CONCLUSIONSThe outline of a newly developed social survey method on traffic noise using the Internet
and the geographic information system (GIS) and its availability are briefly reported. We
have managed to accomplish the initial objective of collecting a large amount of effective
data relatively easy. However, the results of dose-response relationships suggest that we haveto entrust the validity of the method to the future examination. Moreover, considering the freeopinions from the respondents, it is urgently necessary to secure the reliability of the Webbased question survey method as well as research agencies. The newly revised survey method
will be used for future surveys soon and further modification will be made as necessary.
This study is supported by 2006 Subvention of the Ministry of the Environment on
promotion of environmental technological development.
5 REFERENCES[1] J. Kaku, et al., “Standardization of Social Survey Method in Japan,” Proceedings ofINTER-NOISE 02, 2002.
[2] T. Kitagawa, et al., “Estimation of Prediction Method for Narrow-gauge railways,”
Proceedings of the Meeting of ASJ 99, 1999. (in Japanese)[3] Narita Airport Regional Symbiosis Promotion Foundation, “Report of Investigation on
the Health Effects of Aircraft Noise,” March, 2003. (in Japanese)[4] The committee set up by INCE/J, “Comprehensive research on the evaluation of noiseeffects,” The report of the research sponsored by the Ministry of the Environment ofJapan, 2004. (in Japanese)