Control Of Elements Of Waterfront Skylines Of Modern Cities By Using A Quantitative Visual Analysis

Waterfront skyline of the city demonstrates its main characteristics;therefore,its control is one of the key points in urban planning.The waterfront skyline of the modern city consists mainly of skyscrapers,which are different from the former ones not only in size and style but also its location.Earlier the world's tallest building center was located in the United States,but today leadership has moved to the developing countries of Asia,especially to China.There are many related types of research on the visual analysis of the city skyline.However,few types of research are devoted to the quantitative analysis of the design elements in the city skyline.Therefore,the main goal of the study is to find through quantitative research significant factors that have a positive impact on the image of the city skyline.In order to achieve the research goal,the author comprehensively reviewed the related literature sources in this field,clarified the main problems of the waterfront urban skyline,discovered the factors that affect the skyline perception but were neglected,summarized the qualitative and quantitative visual analysis methods,and analyzed existing domestic and foreign urban design guidelines and related research results.According to the literature review,the thesis identifies six factors for visual analysis,including greenery,gap,landmark,layering,angle,and coloring.These factors are relatively significant but have not been fully studied,therefore thorough research is necessary.The author developed two new methods of image generation based on a comparison of existing visual analysis methods and conducted two quantitative studies.The first study is an experimental one;the second is empirical research to verify the results of the first one.The experimental research uses images created from original photos of waterfront skylines but changed beyond recognition.The empirical research uses a half of original images and a half of slightly modified ones.Unlike existing methods,these new methods make it possible to produce images that are closer to the actual scene,especially the method of the empirical research.Although this method limits researchers' ability to manipulate the original image,the results of the research are more accurate because of the presence of more realistic test material.On this basis,based on mean,standard deviation,and standardized mean difference,the author conducted a similar statistical calculation of the two studies.The main conclusions of the thesis are:1)The author found that people prefer 30%of foreground greenery,relatively low landmarks(2.5 times of mean building height),1 or 2 building layers,and 2%width of gaps;2)In experimental and empirical studies,there is a contradiction between the test results of number of layers and percentage of gaps.The author argues that the reason is due to the interference of more significant silhouette factor;3)Existing problems of China's modern waterfront urban skylines include:lack of proper control of the building heights,lack of vegetation in the waterfront,high-density of urban development,ineffective protection of historical silhouette and lack of individuality;4)China's current urban design guidelines are still at a deficient stage,with difficulties in implementation,and with lack of public participation;5)China's urban skyline can be controlled by improving the current urban design guidelines.The author puts forward some suggestions based on the research results.Technical improvements include skyline control on the special district level and on the regulatory detail planning level:height of the landmark,green spaces,and gaps.Political improvements include encouraging of public participation and incorporation of urban design guidelines into the existing planning review system.The technical recommendations are developed to improve the skyline appearance,while the political ones were made to improve the process of design of urban design guidelines and put them into effect.The method of this thesis is designed to help researches evaluate the city skyline through quantitative analysis,and then generate more thoughtful conclusions.In addition,this thesis also enriches and expands the theoretical cognition of the research topics because of its quantitative analysis of series of elements that have not been fully studied.Similarly,this study proposes some suggestions not only to improve the skyline control in China's existing urban design guidelines but also to solve related issues in urban design guidelines in other countries.