The perturbation bound of the extended vertical linear complementarity problem

In this paper, we discuss the perturbation analysis of the extended vertical linear complementarity problem (EVLCP). Under the assumption of the row $\mathcal{W}$-property, several absolute and relative perturbation bounds of EVLCP are given, which can be reduced to some existing results. Some numerical examples are given to show the proposed bounds

Urban square dance in Haidian District of Beijing: Issues and suggestions

With the remarkable success of the 2008 Beijing Olympic Games, the country vigorously advocated the people to actively participate in fitness and exercising nationwide. People responded to the call of government by actively participating in Square Dances, pushing the development of square dance to a climax. Following the development of recent years, such mass culture has prospered among public. There are a lot of parks in Haidian District, Beijing, with a total of 24 parks located around the city center and countryside. The 8 parks mentioned in this paper have high green coverage rate, wide open spaces, and suitable environment for the public to conduct fitness activities. Since these parks are located near residential areas, citizens make them as their first choice to develop leisure and entertainment activities. It is not a rare to have square dance teams occupying the open spaces in the parks. These square dance teams have been established for 2 to 20 years, spontaneously made up by public with different genders, ages and professional background. This paper focuses on the development of square dances in the parks of Haidian District, Beijing and collects its first-hand data through field survey method, thus showing a more comprehensive grasp to the development of square dances in Haidian District. During the organization of such square dance activities, site disputations were occurred as the park was relatively small for the large participating crowd. The level of the square dance teams was uneven, because of lacking professional instructors. Aiming to create an organized and sustainable square dance environment in Haidian District, it is suggested that national and governmental systems and policies should make full use of the social resources available to improve outdoor fitness sites, increase professional square dance instructors and support volunteers, to create a harmonious environment for the society

Real Robot Challenge 2022: Learning Dexterous Manipulation from Offline Data in the Real World

Experimentation on real robots is demanding in terms of time and costs. For this reason, a large part of the reinforcement learning (RL) community uses simulators to develop and benchmark algorithms. However, insights gained in simulation do not necessarily translate to real robots, in particular for tasks involving complex interactions with the environment. The Real Robot Challenge 2022 therefore served as a bridge between the RL and robotics communities by allowing participants to experiment remotely with a real robot - as easily as in simulation. In the last years, offline reinforcement learning has matured into a promising paradigm for learning from pre-collected datasets, alleviating the reliance on expensive online interactions. We therefore asked the participants to learn two dexterous manipulation tasks involving pushing, grasping, and in-hand orientation from provided real-robot datasets. An extensive software documentation and an initial stage based on a simulation of the real set-up made the competition particularly accessible. By giving each team plenty of access budget to evaluate their offline-learned policies on a cluster of seven identical real TriFinger platforms, we organized an exciting competition for machine learners and roboticists alike. In this work we state the rules of the competition, present the methods used by the winning teams and compare their results with a benchmark of state-of-the-art offline RL algorithms on the challenge datasets

Can annual land use plan control and regulate construction land growth in China?

Annual land use plan (ALUP) stands for the quota allocation of land converted to non-agricultural use, which has been in place since 1987 in China. Although the ALUP has been implemented for more than 30 years and has played an important role in China’s non-agricultural land growth management, little has been done to assess the effect of its implementation. The purpose of this research is to evaluate the effect of the ALUP on controlling the growth of construction land in China. The province-level data on land use in China during the period of 2006–2013 were collected and then analyzed using panel data model. The results show that (1) the ALUP can effectively curb construction land growth, and the construction land decreased about 1721 ha with a 1% increment of the intensity of growth management. Construction land growth is closely related to the implementation intensity of the ALUP, which decreases 30,892 ha under strict implementation but increases an extra 181,451 ha with relaxed implementation; (2) the implementation effect of the ALUP shows significant differences between provinces, and the provinces of northwestern and eastern China show better performance than provinces from the southwest and central regions. National development strategy and region’s differentiation land policy may have contributed to this phenomenon; (3) taking both the goal achievement and effectiveness into account, the implementation of the ALUP is described as effective though not completely successful; and (4) for more efficiency and success, the study proposes some suggestions on improving policy implementation in the future

Experimental Study on the Influence of Aging on Mechanical Properties of Geogrids and Bearing Capacity of Reinforced Sand Cushion

Geogrids are widely used in foundation engineering for reinforcing foundations due to their light weight, high strength, and excellent performance. In this study, two kinds of polypropylene biaxial geogrids were used, and indoor thermal oxygen and photooxygen aging tests were carried out. The residual mechanical stability of the exposed materials was determined by tensile testing. The results of both accelerated test methods are discussed and compared in detail. After aging of the geogrid, the trend of tensile strength and fracture elongation change with aging time is obtained. The gray prediction model was used to predict the variation in the retention rate of tensile strength in the geogrid with photooxygen aging time. Model tests of cushions were carried out in a large geogroove to compare the load bearing characteristics of pure sand and the unaged and aged geogrid-reinforced sand cushions. The results show that ultraviolet radiation illuminance plays a decisive role in the aging degree of the polypropylene geogrid. The influence of photooxygen aging on the tensile strength and fracture elongation of a polypropylene biaxial geogrid is greater than that of thermal oxygen aging. Different types of polypropylene biaxial geogrids with photooxygen aging showed different retention rates of tensile strength, and the aging resistance of the geogrid with higher tensile strength was significantly higher than that of the geogrid with lower tensile strength. The tensile strength of the geogrid has an effect on the bearing capacity of reinforced sand cushions. Under proper elongation, the bearing capacity of the reinforced sand cushion is clearly improved compared with that of the unreinforced cushion. The aging behavior of the two geogrids reduces the load bearing capacity of the reinforced cushion by influencing the property of the interface between the geogrid and sand

Multifunctional Drugs-Loaded Carbomol Hydrogel Promotes Diabetic Wound Healing via Antimicrobial and Immunoregulation

Diabetic wound healing poses a significant clinical dilemma. Bacterial infection and immune dysregulation are the predominant reasons. However, conventional wound dressings with a single treatment approach often limit therapeutic efficacy and continue working with difficulty. These limitations cause high treatment failure for diabetic wounds. In this study, we developed a multiple drug-loaded carbomer hydrogel containing Que/Van/Rif (QVR-CBMG) for the simultaneous treatment of infection and immune dysregulation. Honeycomb-like QVR-CBMG hydrogel exhibits excellent abilities to eliminate bacterial infection and biofilms in vitro. Moreover, QVR-CBMG hydrogel possesses an immunomodulatory capacity via affecting the Sirt3/SOD2 signaling pathway to promote M2 macrophages. Furthermore, QVR-CBMG hydrogel effectively promotes wound healing in diabetic rats through several mechanisms. The multidrug-loaded wound dressing not only eliminates bacterial infection and facilitated angiogenesis but also promotes collagen deposition and remodulates the local immune microenvironment in the areas of wounds. In summary, this synthetic strategy to eliminate infection and regulate immune disorders has potential translational value for the prevention and management of diabetic wounds