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The constant interplay between top‐down authority and bottom‐up agency in the production of urban space has invigorated much scholarly debate in urban studies. China, with its astonishingly rapid urban change, offers a fruitful context for empirical investigations. In this article, we seize the opportunity of Shanghai's recent waterfront development to unpack the process by which the local state in Shanghai planned, designed, delivered and governed the city's much‐storied waterfront. Ostensibly framed as an initiative for the people, the development of Shanghai's waterfront was decidedly not by the people. Powerful state actors and their affiliates in universities and architectural firms collaboratively pursued an urban developmental process that paradoxically enhanced residents’ right to urban space and denied citizens’ right to participation. The local state reconciled this apparent paradox by articulating a ‘quality people’ it sought to serve, fabricating an entire profile of their supposed aesthetic values, leisure habits, spatial preferences and luxurious lifestyles. In its essence, this ‘people’ framing represents an extraordinarily cunning approach to state hegemony, enabling the local state to pursue heavy‐handed interventions while upholding a gentle, humanistic ‘for the people’ discourse.

Urban heritage sites in central cities are most difficult to protect during rapid and large scale urban (re)development. Rising land values from property development conflict with and constrain heritage preservation. Compared with many cities in developed and developing countries, large Chinese cities have experienced a stronger redevelopment imperative, faster population growth, and a weaker concern for urban heritages over the last three decades. We use Shanghai to examine the contested evolution of heritage preservation against massive urban redevelopment through three stages from 1990 to the present. Using three heritage projects (Xintiandi, Tianzifang, Bugaoli), we focus on: 1) how each project was implemented and the economic and spatial outcomes each has produced; 2) how the mode of each project’s development interacted with the shifting official policies for heritage preservation; and 3) the implications of the findings, theoretical and practical, for more effective urban preservation.

Since the 1990s, Shanghai has experienced massive urban development and renewal as ways to respond to its demographic, economic, and living space needs. Previous policies have led to the demolishment of many historical communities and valuable heritage housing. The existing ones continue to face extreme threats, such as bad physical conditions and the marginalization of communities. Yet there is a recent trend that emphasizes sustainable urban renewal named microregeneration (微更新), launched by municipal and local states since 2016. One of the main approaches of the initiative was to form new urban coalitions to focus on collaborative governance that helps integrate different agents’ expertise and values for more sustainable urban developments and renewals. This paper explores two cases on how this concept has emerged. The first case is An Shan Si Cun (鞍山四村). This housing block was built in the 1950s for employees of some state-owned enterprises. The second case is Jing Lao Cun (敬老邨). This alley house neighborhood was built in 1930s for migrants who came to Shanghai. Furthermore, this paper is to explore and compare their approaches to sustainable urban renewal, which attempts to preserve these communities that represent cultural and built heritage in Shanghai. Specifically, this paper examines the challenges and accomplishments of these experiments, and discusses policy implications for future tactics of sustainable urban renewal.

Recently, robotic sensor systems have gained more attention annually in complex system sense strategies. The robotic sensors sense the information from itself and the environment, and fuse information for the use of perception, decision, planning, and control. As an important supplement to traditional industrial robots, co-bots (short for co-working robots) play an increasingly vital role in helping small and medium-sized enterprises realize intelligent manufacturing. They have high flexibility and safety so that they can assist humans to complete highly repetitive and high-precision work. In order to maintain robot safe operation in the increasing complex working environment and human–computer intelligent interactive control, this paper is concerned with the problem of applicant accuracy analysis and singularity avoidance for co-bots. Based on the dynamic model with load and torque sensors, which is used to detect the external force at the end of the robot, this paper systematically analyzes the causes of singularity phenomenon in the robot motion control. The inverse solution is obtained by analytical method and numerical method, respectively. In order to ensure the smooth and safe operation in the whole workspace, it is necessary for a robot to avoid singularity. Singularity avoidance schemes are utilized for different control tasks, including point-to-point control and continuous path control. Corresponding simulation experiments are designed to verify the effectiveness of different evasion schemes, in which the advantages and disadvantages are compared and analyzed.

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Gear fault vibration signals are commonly non-stationary, and useful fault information is often buried in heavy noise, which makes it difficult to extract gear fault features. How to select the suitable fault frequency bands is the key to gear fault diagnosis. To address the above problems, a method combining the improved minimum entropy deconvolution (MED) and accugram, named IMEDA, is proposed for extracting gear fault features. Firstly, a selection index based on permutation entropy (PE) and correlation coefficient is defined. Then, the optimal filter length can be effectively selected by the step-length searching method using the proposed index as objective function, and the improved MED is employed to preprocess the gear vibration signals. Finally, the accugram analysis is performed for the preprocessed signals to obtain the optimal frequency band, and the fault characteristic frequencies are extracted from the square envelope spectrum of the signals in the optimal band. The method is validated by gear experimental data with gear wear-out failure. The analysis results demonstrate that the proposed method owns superior effect by comparing with the fast kurtogram (FK), MED combined with FK (MED-FK), accugram and infogram.

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