Photometric redshift estimation of galaxies in the DESI Legacy Imaging Surveys

The accurate estimation of photometric redshifts plays a crucial role in accomplishing science objectives of the large survey projects. The template-fitting and machine learning are the two main types of methods applied currently. Based on the training set obtained by cross-correlating the DESI Legacy Imaging Surveys DR9 galaxy catalogue and SDSS DR16 galaxy catalogue, the two kinds of methods are used and optimized, such as EAZY for template-fitting approach and CATBOOST for machine learning. Then the created models are tested by the cross-matched samples of the DESI Legacy Imaging SurveysDR9 galaxy catalogue with LAMOST DR7, GAMA DR3 and WiggleZ galaxy catalogues. Moreover three machine learning methods (CATBOOST, Multi-Layer Perceptron and Random Forest) are compared, CATBOOST shows its superiority for our case. By feature selection and optimization of model parameters, CATBOOST can obtain higher accuracy with optical and infrared photometric information, the best performance ($MSE=0.0032$, $\sigma_{NMAD}=0.0156$ and $O=0.88$ per cent) with $g \le 24.0$, $r \le 23.4$ and $z \le 22.5$ is achieved. But EAZY can provide more accurate photometric redshift estimation for high redshift galaxies, especially beyond the redhisft range of training sample. Finally, we finish the redshift estimation of all DESI DR9 galaxies with CATBOOST and EAZY, which will contribute to the further study of galaxies and their properties.Comment: Accepted for publication in MNRAS. 14 pages, 9 figures, 11 table

Narrative Representation in Architecture

49 pagesThis booklet explores the term "architectural narrative", which applies a mode of describing architectural events by representing, perceiving and organizing the spaces and signaling design intentions. The booklet discusses the relationship between narrative and architecture, and narrative thinking as a mode of architectural creation. The first part introduces how the methodology can be considered a form of representation, how it illustrates the relationship between storytelling and architecture, and how the two areas influence each other. The second part shows three categories of projects which explored architectural narrative to describe the space and events. In these projects, architectural narrative served the study of body movements, the life of an object, and virtual technology for the design of space

Significance of metro stations and their surroundings: Hong Kong in the anti-extradition protests

Social movements such as the yearlong anti-extradition protests in Hong Kong provide useful and precious materials for us to revisit and visualize social and political significance of metro and light rail stations and their surroundings. We used a mixed-methods approach to draw various useful information from police records, newspapers, social media, and/or site audits to compile a list of large-scale protests and sit-ins occurred in Hong Kong between June and August 2019. We attempt to show (1) in high-density and transit-reliant cities like Hong Kong, transit services play an important role in people\u27s daily mobility on both normal days and protest days; (2) on protest days, transit services, related facilities (e.g., entrances, lifts, and platforms) and surrounding areas can become the focuses/battlefields for both the government and the protesters; (3) we still know little about how protests and transit services/usage are related but smartcard data can help us fathom the issue

Developing metro-based accessibility: Three aspects of China’s Rail+Property practice

Populous Chinese cities have invested heavily in metro systems and planned proactively for transit-oriented development. Rail plus property (R+P) programs, where metro corporations engage in, and even orchestrate real estate development in or around rail station areas, have been recurrently reported among these cities. However, careful assessment of these programs is still rare in the existing literature. Built upon multiple R+P programs led by Shenzhen Metro Cooperation and/or Hong Kong Mass Transit Railway Cooperation, this article fathoms the rationale for R+P programs in Mainland China, the obstacles for oversea private investors’ participation and the balance between profit making and social goods supply. It finds that R+P programs serve as alternative funding sources for expensive metro projects. It decreases municipal governments’ cash flow contribution to those projects, which is mandated by the central government. In addition, local business environment for R+P projects has disadvantaged private sector participation, especially those private investors from overseas. Furthermore, public subsidy to local metro corporations is likely to persist as R+P programs have not been designed for economic value maximization; rather, they are in place because (1) they reduce the cash flow burden of the municipal government; (2) they are tasked by the municipal government to produce a considerable number of affordable public housing