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Purpose One of the development trends of robots is to enable robots to have the ability of anthropomorphic manipulation. Grasping is the first step of manipulation. For mobile manipulator robots, grasping a target during the movement process is extremely challenging, which requires the robots to make rapid motion planning for arms under uncertain dynamic disturbances. However, there are many situations require robots to grasp a target quickly while they move, such as emergency rescue. The purpose of this paper is to propose a method for target dynamic grasping during the movement of a robot. Design/methodology/approach An off-line learning from demonstrations method is applied to learn a basic reach model for arm and a motion model for fingers. An on-line dynamic adjustment method of arm speed for active and passive grasping mode is designed. Findings The experimental results of the robot movement on flat, slope and speed bumps ground show that the proposed method can effectively solve the problem of fast planning under uncertain disturbances caused by robot movement. The method performs well in the task of target dynamic grasping during the robot movement. Originality/value The main contribution of this paper is to propose a method to solve the problem of rapid motion planning of the robot arm under uncertain disturbances while the robot is grasping a target in the process of robot movement. The proposed method significantly improves the grasping efficiency of the robot in emergency situations. Experimental results show that the proposed method can effectively solve the problem.

Human activities during each phase of coal mine life cycle greatly affect groundwater environment. The groundwater environment destruction is not just only the destruction of underground structure but also the social problems caused by available groundwater resources reduction, as well as the environmental problems affecting ecosystem and human health. Moreover, the groundwater environmental risk of coal mining is complex, dynamic, and long-term. Therefore, a framework and quantitative method for groundwater environmental risk analysis at different phases of the mine life cycle was presented, which is composed of the groundwater system destruction risk (GSDR) and social-economic-ecological vulnerability (SEEV) assessment. The framework was applied in Hongshan abandoned coal mine, North China. Based on the aquifer structure destruction, groundwater flow field evolution, contamination, and social-economic influence analysis, 12 main controlling factors for the GSDR and 7 factors for the SEEV were determined and quantified separately. The results showed that the groundwater contamination of the Hongshan mine mainly occurred after closure, caused by the cross-strata pollution of mine water, which significantly reduced the groundwater available resources, which greatly affected local social-economy sustainable development and residents’ health. The Hongshan mine closure increased groundwater environmental risk, with the GSDR high-risk zone being 12.51 km2 larger than that during the mining phase and the SEEV was calculated at a high level. This framework promotes systematic integration of the groundwater environmental risk assessment in mine life cycle.

The interactions between groundwater and its environment was investigated in prairie mining area in this study, through the groundwater system evolutions in mining area before and after the mining actions (from 1973 to 2016) of Yimin coal mine. The results showed that (1) the mining activities of the open-pit coal changed the original reduction environment into the oxidizing environment in the mining area. The pyrite and sulfur-bearing coal in the stratum oxidized, produced acid and triggered a series of subsequent reactions, resulting in the decrease in the pH value of the groundwater in the mining area. The concentration of SO42-, Fe2+, Fe3+, Ca2+ and Mg2+ and the total hardness increased. The regional hydrochemical type evolved from HCO3-Na·Ca·Mg type before mining to the type of HCO3·SO4-Na·Ca·Mg after mining. (2) Coal mining strongly draining underground water accelerated the regional groundwater circulation, and then made the groundwater desalination. The concentrations of TDS, COD and Na++K+ in the mining area all showed a decreasing trend. (3) The coal mining activities made the calcite and dolomite in saturated state under the natural condition of underground water to be unsaturated again. The hydro-geochemical action evolves from double control (water-rock interaction and evaporation-concentration) to water-rock interaction control.

Net zero energy buildings (NZEBs) are energy efficient buildings that incorporate renewable energy generation systems so as to produce sufficient renewable energy to at least offset the total amount of non-renewable energy used by the building on an annual basis. NZEB technologies have widespread commercial and residential application, but their feasibility and efficacy in the livestock sector in support of sustainable intensification have received little attention. This study quantifies the potential for such technologies to improve sustainability outcomes in the livestock sector based on an ISO 14044-compliant life cycle assessment of a pilot net zero energy laying hen facility in Alberta, Canada compared to a conventional facility. It was found that direct energy inputs account for 6.47% and 31.64% of the life cycle cumulative energy use of egg production in NZE and non-NZE hen housing, respectively. Average infrastructure-related contributions to the life cycle impacts of egg production are only 4.34% and 1.94% for the NZE and non-NZE barns, but NZE technologies reduce the net impacts of egg production by 0.89–64.82%. The environmental impact payback time for the NZE barn (30-year lifespan) ranges from 1.38 to 20.66 years, considering the largely fossil fuel-based electricity grid in Alberta, which indicates that non-trivial environmental benefits would accrue across impact categories considered. However, this could vary considerably elsewhere depending on the types and amounts of green energy utilized in regional grid mixes. The type and availability of renewable energy resources that are integrated into NZE barns will similarly be important in determining the potential of such technologies to support sustainable intensification in this sector.

Design of highly efficient electromagnetic wave (EMW) absorbing materials with continuous dual-absorption peaks is a hot topic but a challenge in anti-electromagnetic interference and pollution fields. Herein, we developed an interfacial modulation strategy to achieve this goal in dielectric nanocomposite and clarified the interface function and relevant mechanism. Experimentally, CuS/Ag 2 S composite with tunable heterointerface was fabricated by decorating Ag 2 S nanoparticles on CuS flakes via cation-exchange reaction. By changing the Ag 2 S loading, the heterointerface between Ag 2 S and CuS induced strong dielectric resonant peak and improved impedance matching, which resulted in the significant enhancement of EMW absorption and the appearance of continuous dual-absorption peaks in CuS/Ag 2 S composite. With a rather low filler loading of 20 wt% and a thin layer thickness of 2.89 mm, the optimized CuS/Ag 2 S composite exhibited continuous dual-absorption peaks with reflection losses of −47.2 and −20.6 dB, respectively. The proposed interfacial modulation strategy may potentially be used to fabricate other highly efficient dual-absorption absorbers.

Energy retrofits are significant in improving the energy efficiency of existing residential buildings (ERB) and mitigating greenhouse gas emissions. While many countries have introduced relevant retrofit policy instruments (RPIs), retrofit rates are still relatively low due to various complications in practical implementation. This study aims to organize the scattered information related to RPIs and their implementation, success, and obstacles across different countries and provide valuable references for retrofit strategy development. This article examined various RPIs for ERB in 11 selected countries. The investigated RPIs were grouped into four categories: direction and command, assessment and disclosure, research and service, and financial incentives. The RPIs implementation approaches in the surveyed countries were summarized and compared. Furthermore, obstacles to the uptake of retrofit schemes were identified. Finally, policy recommendations to overcome the obstacles and improve the penetration of retrofit schemes were proposed. This study can assist policy makers and other stakeholders in gaining a holistic view of RPIs and their implementation in the residential buildings, understanding the barriers to the uptake of retrofit schemes, and developing more efficient RPIs in the future.

Two-wheeled robots have many advantages over other mobile robots, but they are difficult to self-balance compared with other wheeled robots. Reinforcement learning (RL) is a general framework for sequential decision-making problems. So far, there are many applications of reinforcement learning to solve robot control problems, but most of them are used in simulators because of the large amount of data required. In addition, due to the reality gap, the policy learned in a simulation environment cannot be transferred directly to a real robot. Real robot data often expensive due to the potential damage to the robot. Model-based methods require far fewer robot data than model-free methods, but these methods have the problem of model bias. In this paper, we use a model-based reinforcement learning method to achieve self-balance of a two-wheeled robot. We present a model learning method that can reduce the problem of model bias. Our method combines the simulator and a few real robot data to learn a probabilistic dynamics model of the robot through an iterative way, which requires no expertise and can learn from scratch. Then the control policy is optimized based on the learned model.

As the robot gradually develops from indoor to outdoor, multi-sensor fusion is increasingly being applied to the field of robot perception. Among them, LiDAR and binocular sensors are most widely used. Robots use the complementary and redundant data they provide to perform environmental perception and implement certain functions of the robot, such as SLAM, autonomous obstacle avoidance and so on. However, the data obtained by each sensor are relative to its own coordinate system. Data must be converted to a unified coordinate system before data fusion. Therefore, the calibration of the transformation among sensors is the first problem to be solved in data fusion. Moreover, the accuracy of calibration is directly related to the effect of data fusion. Therefore the calibration between sensors is very important and necessary. In this paper, we propose a novel method to find accurate rigid-body transformation for the extrinsic calibration of a 3D LiDAR and a stereo cameras, using two Aruco calibration boards. Also the validity of the algorithm is demonstrated by some experiments.

Vision-based solution is a popular research for 6-DOF state estimation in recent years. All of these algorithms are based on the assumption that surrounding is static. Actually, in a highly dynamic environment, estimated state is mixed, including robot and dynamic objects. To this end, an approach for detecting dynamic objects based on the velocity of feature points is proposed in this paper. Our approach establishes the model of the velocity of feature points and separates dynamic objects motion from the mixed motion by comparing the velocity of IMU (inertial measurement unit) and feature points. Finally, the detection results of dynamic feature points on the left and right cameras’ front and rear frames are fused and verified to eliminate the influence of noise and mismatching. Experimental results prove that our approach can get more accurate state estimation, which shows that this method is effective in high dynamic environments.

A novel visible-light-responding InVO4-Cu2O-TiO2 ternary nanoheterostructure was designed on the basis of the strategy of energy gap engineering and prepared through ordinary wet chemistry methods. The as-prepared nanoheterostructure was characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and diffuse reflectance ultraviolet-visible spectroscopy (UV-vis/DRS). The TEM and HRTEM images of 10%InVO4-40%Cu2O-50%TiO2 confirm the formation of nanoheterostructures resulting from contact of the nanosized TiO2, Cu2O and InVO4 in the size of 5–20 nm in diameter. The InVO4-Cu2O-TiO2 nanoheterostructure, when compared with TiO2, Cu2O, InVO4, InVO4-TiO2 and Cu2O-TiO2, shows significant enhancement in the photocatalytic performance for the degradation of methyl orange (MO) under visible-light irradiation. With a 9 W energy-saving fluorescent lamp as the visible-light source, the MO degradation rate of 10%InVO4-40%Cu2O-50%TiO2 reaches close to 90% during 5 h, and the photocatalytic efficiency is maintained at over 90% after six cycles. This may be mainly ascribed to the matched bandgap configurations of TiO2, Cu2O and InVO4, and the formations of two p-n junctions by the p-type semiconductor Cu2O with the n-type semiconductors TiO2 and InVO4, all of which favor spatial photogenerated charge carrier separation. The X-ray photoelectron spectroscopy (XPS) characterization for the used 10%InVO4-40%Cu2O-50%TiO2 reveals that only a small shakeup satellite peak appears for Cu(II) species, implying bearable photocorrosion of Cu2O. This work could provide new insight into the design and preparation of novel visible-light-responding semiconductor composites.

With the rapid development of urbanization worldwide, there is a large volume of neighborhoods that need to be renewed with various problems such as poor building performance, few public facilities, congested road traffic, unequal living standards, disappearing community culture, and deprived environments. Performance evaluations are considered to be useful tools for ensuring the outcomes of sustainable renewal. Although many research works have assessed the performances of urban renewal projects, evaluations, especially for neighborhood renewal projects, are often overlooked. Besides, it is also hard to find a general standard that is suitable for evaluating the performance of any neighborhood renewal project with a lack of related regulations or codes. Thus, this paper intends to build a framework to assess the relative performances of multiple neighborhood renewal projects through a hybrid AHP-TOPSIS method. A case study in Nanjing, China, is used to show how this framework could be applied to decision-making in order to pursue sustainable neighborhood renewal. The results are expected to provide references for sustainable renewal in each neighborhood. Suggestions related to the findings are proposed to further improve the performances of neighborhood renewal projects, such as establishing a multiple principle&ndash, agent framework, providing a sustainable funding system from both the public and private sector, and implementing multiprogram management measures.

High-tech minerals (HTMs) used for manufacturing mobile phones are indispensable raw materials for emerging Chinese national strategic industries. China is the world’s largest mobile phone market, and increasing amounts of HTMs are found in the country’s excessive mobile phone waste. Thus, it is important to investigate the life cycle cost (LCC) of recycling HTMs from waste mobile phones. In this study, material flow analysis (MFA) and LCC assessment were conducted to analyze the recycling of waste mobile phones and the contained HTMs. The LCCs of recycling two types of mobile phones, i.e., feature phones and smartphones, were investigated. The results show that the LCCs of recycling one waste feature phone and one waste smartphone are approximately US$ 2.34 and US$ 6.60, respectively. The LCCs of extracting HTMs from one waste feature phone are US$ 6.035 for 1 g of cobalt and US$ 0.014 for 1 g of palladium, while the LCCs of extracting 1 g of cobalt, palladium, antimony, beryllium, neodymium, praseodymium and platinum from one waste smartphone are US$ 10.106, US$ 0.024, US$ 0.135, US$ 0.005, US$ 0.08, US$ 0.016 and US$ 0.006, respectively. Based on the LCC results, constructive suggestions and policy implications are provided for future mobile phone management in China.

This paper investigates the requirements of Chinese and ASHRAE HVAC design manuals and codes for various types of buildings within the power plants. By analysing the characteristics of HVAC basic design criteria for different building areas, the summary of similarities and differences between these two design systems are found. This paper studies the applicability and adaptability of Chinese HVAC design system as an auxiliary design basis in foreign power plant project, aiming to provide the basis for the selection of HVACdesignfor foreign design of power plant projects.

Green roofs are well-known as a sustainable construction practice. Economical benefits of green roofs have been widely discussed by many researchers. This chapter starts with an extensive literature review on the benefits and costs of green roofs. The quantitative estimates of individual and public benefits of green roofs were conducted, and lifecycle costs of green roofs from cradle to grave were analyzed. The net present values per unit area of a green roof were accessed by considering the individual benefits, public benefits, and lifecycle costs. A comparable assessment was performed to evaluate the payback period of green roofs in different markets. The analysis demonstrated that the lifecycle cost of green roofs can be paid back by individual benefits in a mature market. If the public benefits are added into the assessment, the lifecycle cost of green roofs can be retrieved in most of the markets.

Sustainable building practices can considerably reduce building's environmental impact in energy consumption. Covering a building envelope with green vegetation, such as green roof and green wall, is considered a sustainable construction practice, as green vegetation has a positive performance in energy savings. It reduces heat flux and solar reflectivity, generates evaporative cooling, increases thermal performance of the building envelope, and blocks the wind effect on the building. This paper analyses the energy performance of green vegetation in a high occupancy LEED Gold standard building in Canada. DesignBuilder software was used to model the energy consumption for heating and cooling, and EnergyPlus software was used to perform the detailed energy simulations. The developed simulation model was validated with the actual energy consumptions of the selected building. Three different scenarios of green vegetation were simulated and the results show that green vegetation could considerably reduce the negative heat transfer through the building facade in summer and winter months. However, the analysis demonstrated that the green vegetation is not cost-effective in winter months or cold climatic regions due to the low energy savings performance. The paper concludes with recommendations to improve the overall energy performance in green buildings.

Covering a building envelope with green walls is considered a sustainable construction practice. Green walls can be classified as green facades or living walls based on their purpose and characteristics. Living walls are built with different layers and variable planting styles depending on the geographic location, function, and weather conditions. This paper discusses a comparative lifecycle assessment (LCA) of three living wall systems: trellis system, planter box system, and felt layer system. Chemical emissions and energy consumption of the living wall materials are evaluated in the whole lifecycle, and compared with the chemical absorption and energy savings of operational living walls. The results demonstrated that the felt layer system is not environmentally sustainable in air cleaning and energy saving compared to the trellis system and modular panel system. The environmental performance of living walls is influenced by the types of materials and plants chosen for the systems, as well as the external factors, such as climate and building type. The LCA indicates the need of environmental friendly materials for sustainable living walls.

Smart city is originally aimed at dealing with various urban problems due to rapid urbanization, like energy shortage, congestion, and environmental pollution. The Chinese government has been devoting to the promotion of smart cities for many years. However, it is unconfirmed whether the city is more resilient with all the modern technologies provided when unexpected predicaments like climate changes or disasters occur. Therefore, it is urgent to consider resilience in the smart city. This paper provides a MCDM approach to assess and rank the resilience of 187 smart cities in China. The results demonstrate that the overall resilience of smart cities is at a relatively low level. There is also a significant unbalance of resilience between smart cities due to different infrastructural, economic, social, institutional, and environmental conditions. The potential links between urban smartness and resilience were also explored, and the results showed significant positive relationship between the smartness of a city and its resilience. Evidence also proved that developing smartness is more or less useful for improving urban resilience. Suggestions such as strengthening the development of infrastructure and economy, and enhancing the multi-stakeholders’ cooperation are proposed to further promote the smart and resilient development in China.

As the unsatisfied environment of the fossil fired power plant become more controversial and disputable, the current tendency of enclosed coal yard which helps to decrease air pollution gains more application than those open ones. In order to improve the indoor environment and ventilation effect as well as to achieve good energy conservation at the same time, this paper investigates the ventilation effect of the roof vortex flow natural ventilator. By using multivariate nonlinear regression analysis and the theoretical calculation of natural ventilation, this paper proposes an instructive natural ventilation model and calculation method of enclosed coal yard based on the indoor pollutants concentration control, which is highly recommended as a good design application in similar enclosed coal yard buildings.

Laparo-endoscopic single-site surgery (LESS) with its unique advantages has become the focus in the minimally invasive surgery. However, the existing LESS robots are mostly given open loop control for its arm, which is difficult for the doctor to handle the surgical instruments. In this paper, A magnetic anchor robot for LESS was designed, which can be inserted into peritoneal cavity through just one incision. We use master-slave control system based on visual feedback to achieve closed-loop control for the robot arm. To extract image feature information, we used a pin-hole camera geometry and made mark points on the robotic arm and proposed a marker point coordinate algorithm to realize the real-time stability control of the robot arm. The equivalent model of robotic platform is established and the master-slave control program based on visual feedback is verified by experiment to be feasible.

The aim of this study was to investigate whether phosphorylated Radix Cyathulae officinalis Kuan polysaccharides (pRCPS) used as adjuvant with foot-and-mouth disease vaccine (FMDV) can stimulate specific humoral and cellular immune responses in ICR mice. The results demonstrated that pRCPS significantly up-regulated FMDV-specific IgG, IgG1, IgG2b and IgG2a antibody levels and splenocyte proliferation. pRCPS also promoted the killing activities of cytotoxic T lymphocytes (CTL) and natural killer cells (NK). In addition, pRCPS enhanced the expression levels of IL-2, IL-4, and IFN-γ in CD4+ T cells and the level of IFN-γ in CD8+ T cells. Importantly, pRCPS enhanced the expression of MHCII, CD40+, CD86+, and CD80+ in dendritic cells (DCs). This study indicated that phosphorylation modification could increase immune-enhancing activities of RCPS, and pRCPS could promote humoral and cellular immune responses through facilitating DC maturation.

Automation design is of great significance to promote design quality and reduce design cycle for pipeline system design. But high complexity and strong design interference are two main problems in automation design process of pipeline system. Thus, this study proposes a novel layout space model to reduce high complexity and design interference in automation design of pipeline system. The proposed model uses grid methods to provide candidate layout space. The candidate layout space adopts random sampling to meet requirements of reducing complexity and design interference. Test experiment is provided to show that the proposed model is effective.