Art history and theory department

The use of high-density remote sensing buoys and ship-based observations play an increasingly crucial role in the operational assimilation and forecast of oceans. With the recent release of several high-resolution observation datasets, such as the Global Ocean Data Assimilation Experiment (GODAE) high-resolution SST (GHRSST) datasets, the development of observation-thinning schemes becomes important in the process of data assimilation because the huge quantity and dense spatial-temporal distributions of these datasets might make it expensive to assimilate the full dataset into ocean models or even decay the assimilation result. In this paper, an objective model simulation ensemble-based observation-thinning scheme is proposed and applied to a Chinese shelf-coastal seas eddy-resolving model. A successful thinning scheme should select a subset of observations yielding a small analysis error variance (AEV) while keeping the number of observations to as few as possible. In this study, the background error covariance (BEC) is estimated using the historical ensemble and then the subset of observations to minimize the AEV is selected, which is estimated from the Kalman theory. The authors used this method in the GHRSST product to cover the shelf and coastal seas around China and then verified the result with an estimation function and assimilation-forecast systems.

Proper orthogonal decomposition (POD) and singular value decomposition (SVD) methods are used to study a finite difference discretization scheme (FDS) for the tropical Pacific Ocean reduced gravity model. Ensembles of data are compiled from transient solutions computed from the discrete equation system derived by FDS for the tropical Pacific Ocean reduced gravity model. The optimal orthogonal bases are used to reconstruct the elements of the ensemble with POD and SVD. Combining the above approach with a Galerkin projection procedure yields a new optimizing FDS model of lower dimensions and high accuracy for the tropical Pacific Ocean reduced gravity model. An error estimate of the new reduced order optimizing FDS model is then derived. Numerical examples are presented illustrating that the error between the POD approximate solution and the full FDS solution is consistent with previously obtained theoretical results, thus validating the feasibility and efficiency of POD method.

In this paper, the tropical Pacific Ocean reduced gravity model is studied using the proper orthogonal decomposition (POD) technique of mixed finite element (MFE) method and an error estimate of POD approximate solution based on MFE method is derived. POD is a model reduction technique for the simulation of physical processes governed by partial differential equations, e.g., fluid flows or other complex flow phenomena. It is shown by numerical examples that the error between POD approximate solution and reference solution is consistent with theoretical results, thus validating the feasibility and efficiency of POD method.

The "equation-free" (EF) method is based on a procedure, which is often used in complex, multi-scale problems, given an initial macroscopic variable, by lifting, evolve in Direct Numerical Simulations (DNS), restriction, and projective integration. In this paper, we apply the Equation-free method to the reduced modeling of a large-scale upper ocean circulation in the tropic Pacific domain. We carry out a series of experiments to discuss its convergence and error, and we also discuss some factors that affect the results, such as the number of snapshots and basis functions based on proper orthogonal decomposition (POD) mode, large-scale time step, short time step and the number of iterations during the course of the DNS running in a large-scale time step. Compared with POD method, we do not need availability of explicit equation or right-hand-side (RHS), and we may obtain better results for horizontal velocity components of depth-averaged currents than those obtained in POD case. The results from the equation-free based on different POD modes are compared with results of POD and DNS. We also illustrate the convergence and error of the EF method. The main findings are: we reduce the computation work enormously in contrast to DNS, for instance, the computational cost of the equation-free POD-assisted method is less than 10% of that for DNS. The method can capture the main variability by a low dimensional system based on equation-free POD mode. We also attained a RMS error for the upper ocean layer thickness that is less than 1m i.e. less than 1% of the average thickness and the correlations between the upper layer thickness are around 0.99 based on equation-free POD method, while the convergence and the error are illustrated through numerical experiments. (I.M. Navon).

Editor. "Inside the White Cube" is a Chinese-language anthology of texts first published in Artforum International Magazine. For the first time, these essential art historical milestones are made available to Chinese audiences.

The table of contents and editor's introduction (Chinese only) are available here for download.

Editor, author, translator. Bilingual catalogue raisonné for He An. Includes curatorial essay, artist's writing in Chinese and with English translation. (For download, see below.)

Published on the occasion of He An's solo exhibition "Jade Branch," at Tang Contemporary Art, Beijing, December 2019–February 2020.

This introduction situates the conversation between Hsieh Teh-Ching, Ai Weiwei and Xu Bing within a larger historic and socio-cultural framework, as well as elaborates a brief history of the publication in which the conversation was first published, The Black Cover Book. The text also elaborates on the unarticulated issues informing their discussion, such as their émigré status, and briefly outlines a history of the artists' work at the time of the conversation. The work of other avant-garde artists in the Chinese diaspora whose work was published in The Black Cover Book is also touched upon briefly. This introduction reclaims some of the history behind the publication and argues for understanding the act of self-publication as not only a new conduit for artistic interaction but also a political act. Furthermore, it argues that it not only congealed an emerging art movement on Mainland China, but that this avant-garde and conceptual art movement was, at its very core, defined by...

This thesis compares Art Movement (New Wave Art) in China with that in Korea in 1980s. Although both of them arise around the same time, there are huge differences between them in that Abstract Expressionism and Realism, and a ideological emancipation and a pro-democracy movement. 
  Art movements of the two countries reflect reality and oppose to existing traditional art. Comparing character, space and time in work of a Chinese artist whose name is Wang Guangyi, Frozen North Pole No.1 and work of a Korean artist whose name is
Min Junggi, Conversation, it turns out that they have western surrealism language in common.
Surrealism language which is represented by Giorgio De Chirico, Rene Magritte and Salvador Dali is manifested by artists of China and Korea not only in expressions of character and space-time but also in application of collage. Focusing on this point, this paper deals with how surrealism could be absorbed and presented in painting of China and Korea, what the similarities and differences are and what roles of the times and surrealism language.
Artists of China and Korea intend to show the reality that is being faced by using surrealism language. They express their thought about reality, either directly or indirectly. Although aspect of visual language has changed, it is the result of following the stream of times. Artists who reflect reality into their works contribute to establish a basis of modernity of contemporary art.
This study examines whether the common denominator which is found in Art Movements of both countries in 1980s is certainly surrealism language, and finally ruminates on the  modern  essence of contemporary art through painting of Art Movement.