1 Introduction
With the rapid development of the country's urbanization process, the city's appearance is also changing with each passing day. As an important part of urban construction, the construction of urban night light environment has become an important window to show the city's appearance and show the achievements of urban development. Compared with the more mature light environment such as urban commercial area and public open space, the research on outdoor light environment in urban residential areas is slow. There are few studies on outdoor light environment assessment in residential areas at home and abroad. The existing research results are mostly oriented to objective factors such as road traffic and night safety, and lack of other higher-level requirements including residents' health, convenience, comfort and sustainability. .
In particular, it has not been more appropriate to establish a comprehensive and objective assessment tool for the characteristics of domestic residential areas. In the design, construction and evaluation of outdoor lighting in residential areas, it mainly refers to foreign standards and domestic standards, such as the publication of the International Lighting Association (C IE) No. 92 publication, "City Lighting Guide", Ministry of Construction of the People's Republic of China Urban Road Lighting Design Standards (C JJ 45-2006), etc., lacks technical standards and norms that are more in line with the actual needs of lighting construction in residential areas in China.
Therefore, based on the theoretical research in the field of urban environmental assessment at home and abroad, this paper collects assessment opinions from experts based on the subjective needs of residents. After statistical analysis, it summarizes the evaluation indicators and evaluation indicators related to the outdoor light environment assessment in residential areas. And in-depth discussion of the interrelationship between the various evaluation indicators. It is expected to be used as the basis for establishing the outdoor light environment assessment system architecture of residential areas in China, and can provide reference for policy research and implementation in related areas.
2 Light and environmental related results in residential areas at home and abroad
Compare and widely collect research results related to “light environment in residential areas†at home and abroad, especially the specifications, standards and guidelines currently in use, and analyze and contrast the contents of “light environment in residential areasâ€.
According to the analysis, these specifications can be divided into two categories: “urban area lighting†and “road function lighting†according to the research content. Then, the research content is divided into 16 individual items such as night road safety, road lighting energy consumption, installation and maintenance of lamps, energy-saving control, etc., and these individual items are analyzed correspondingly with each specification. The specific results can be seen in Table 1.
3 Evaluation indicator group establishment
Through the expert interview and comparative analysis, the 16 individual indicators obtained from the preliminary analysis were further reclassified. A total of 12 interview experts, according to their research areas can be divided into: 3 buildings, 2 urban planning, 2 landscape ecology, 5 urban lighting. Based on the expert opinion, the above individual indicators are divided into five categories: “safetyâ€, “healthâ€, “convenienceâ€, “comfort†and “sustainability†[2], where “security†can be decomposed into “Traffic safetyâ€, “life safety†and “night safety precautionâ€; “health†can be decomposed into “indoor living health†and “outdoor activity healthâ€; “convenience†can be decomposed into “convenient transportation†and “service facilities†"Convenience"; "comfort" can be decomposed into "community comfort", "beauty comfort" and "resident privacy"; "sustainability" can be decomposed into "economic sustainability" and "environmental Persistence", as shown in Figure 1 [3-12].
4 evaluation factor selection
According to the sub-items obtained by the decomposition index group, the specifications are again integrated, and 43 evaluation indicators related to each sub-item are obtained, as shown in Table 2. Among them: 14 safety, 4 health, 7 convenience, 12 comfort, and 6 sustainability [13-19].
5 fuzzy Delphi method screening evaluation indicators
Fuzzy De lph iM ethod is an important statistical forecasting method in group decision-making process. It mainly integrates the opinions into the fuzzy number by obtaining the consensus of the relevant personnel on the questionnaire response and using the concept of cumulative number and fuzzy integral. To seek a determination of the consensus opinion of a particular forecasting object. This time, the “simple center of gravity method†was used instead of “average numberâ€. As an indicator to judge the consensus of the questionnaire, the evaluation indicators were screened.
A total of 60 questionnaires for evaluation indicators were distributed and 48 valid questionnaires were collected, with an effective rate of 80%. There were 20 “academic researchers†and 28 “residents†in the valid questionnaire.
1 Questionnaire reliability and validity analysis
1) Reliability analysis [20]
Reliability refers to whether the results obtained in this survey are consistent. This time, the “KS verification method†is mainly used as the verification statistical method for reliability analysis. The results of the analysis show that, under the confidence level of 93%, except for “a-8 game area lightingâ€, the D value is 0.189 (the significant level threshold is 0.220), and the “-j 2 indoor activity†D value is 0.205 (its significant level) The critical value is 0.235), the "s-5 background light comfort" D value is 0.212 (the significant level threshold is 0.243), and the "k-5 test and engineering acceptance" D value is 0.209 (the significant level threshold is 0.33) In addition, 90.2% of the evaluation indicators have D values ​​greater than their significant level thresholds, indicating that the results of this survey are consistent and consistent with the normal distribution.
2) Validity analysis [ 21]
Validity refers to whether the questionnaire can truly measure the problem to be studied and whether the results are “authenticâ€. This time, the “experience method†was used to determine the concentration trend, with 68% of the results falling on the average (a) plus or minus one standard deviation (a) as the standard. The results show: In addition to "a-8 game area lighting", "a-11 action recognition", "s-5 background light comfort", "s-7 flower bed landscape lighting", "k-5 inspection and engineering acceptance In addition to failing to meet the standards, the remaining 87.8% of the evaluation indicators can meet the concentration trend.
Through the above reliability and validity analysis, it can be seen that the individual samples in this questionnaire have consistency and authenticity in the evaluation indicators, and the questionnaire has the use value.