A novel six-axis force/torque sensor (F/T sensor) for an Experimental Module Manipulator (EMM) in the Chinese Space Station (CSS) is developed in this paper. First, we designed the elastomer ...structure of the F/T sensor and used the analytical method and the finite element method to analyze the strain, in order to accomplish the strain gauges' layout. Then, the electrical system was designed, which mainly realizes the acquisition of force/torque information, temperature and serial communication with the end effector (EE). Following this, we analyzed and designed the adaptability of the F/T sensor to the space environment. After this, the manufacturing process of the sensor was introduced in detail, and the F/T sensor was calibrated by a pulley weight system. Finally, the sensor was tested on the space environment adaptability of mechanical vibration and thermal vacuum on the ground. The test results show that the developed sensor has the ability to accurately measure three-dimensional force and three-dimensional moment information on orbit, which provides necessary conditions for the on-orbit fine operation of EMM.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
How to make efficient data routing in energy constrained wireless sensor networks (WSNs) is one of the key points. In order to find the optimal path of data transmission in the WSNs, a new routing ...algorithm based on ant colony algorithm is proposed. Using the improved heuristic function and considering the node communication transmission distance, transmission direction, and residual energy, an optimal path from the source node to the destination node can be found. Thus, the network energy consumption is reduced and the network lifetime is prolonged. Simulation results show that new ant algorithm can effectively save the energy of nodes and prolong the network lifetime.
•Occupant behaviors are clustered for residential buildings energy consumption estimation.•Clustered occupancy schedules are distinctive to ASHRAE schedule.•Bottom-up and simulation models were ...utilized to validate the results.•Applied the reliable ATUS and RECS datasets.
In residential buildings, occupant behavior and occupancy status have a significant impact on energy consumption variation. Although the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) recommends a uniform occupancy schedule for building energy assessment, occupant behavior patterns and schedules could be different for each building due to occupants’ lifestyles, preferences, occupations, and other differences. Existing occupant behavior models focus on analyzing occupants’ sociodemographic characteristics to predict their energy consumption with statistical approaches. This paper proposes to identify and classify occupants’ behavior with direct energy consumption outcomes and energy time use data through unsupervised clustering. Based on the American Time Use Survey (ATUS), the proposed approach integrates k-modes clustering and demographic-based probability neural networks and identifies 10 distinctive behavior patterns. With the results of the behavior classification and simulation, a bottom-up engineering model reveals that the proposed behavior model offers a more accurate and reliable prediction than the ASHRAE standard schedule. With qualified and sufficient time use data, the model is capable of automatically estimating energy consumption on even larger geographic scales.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Emerging multidrug resistance (MDR) to chemotherapy is a major obstacle in successfully treating malignant diseases. Nanotechnology provides an innovative and promising alternative strategy compared ...to conventional small molecule chemotherapeutics to circumvent MDR. This review focuses on recent literature examples of nanotechnology applications to overcome MDR. The advantages and limitations of various nanotechnologies are discussed as well as possible approaches to overcome the limitations. Developing a practical nanotechnology-based drug delivery system requires further studies of the tumor microenvironment, the mechanisms of MDR to chemotherapy, the optimal dosage regimen of anticancer drugs and/or siRNA, the transport kinetics of nanocarriers in tumor stroma and the pharmacokinetics of drug-loaded nanocarriers within MDR tumor cells.
Schematic depiction of nanotechnologies used to overcome MDR in tumors (issues surrounding the sphere) and further knowledge needed in this field (corresponding label to the technology). Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Collaborations (e.g. renewable energy sharing) among nearly zero energy buildings can improve performances at cluster level. Demand response control is helpful to enable such collaborations. Existing ...studies have developed some dynamic pricing demand response control methods to reduce the nearly zero energy building cluster’ electricity bills and eliminate the power grid's undesirable peaks. However, in these controls the collaborations among buildings are not allowed/enabled, since each building interacts with the grid and there is no direct interaction among buildings. Meanwhile, for performance optimizations at building cluster level, the computation costs of these non-collaborative controls are excessively high especially as a number of buildings considered. Therefore, this study proposes a collaborative demand response of nearly zero energy buildings in response to dynamic pricing for cluster-level performance improvements. Considering the building cluster as one ‘lumped’ building, in which the renewable generations, energy demands and battery capacities of individual buildings are aggregated, the collaborative control first identifies the optimal performance at cluster level in response to the dynamic pricing. Then, based on the identified optimal performance, the proposed control coordinates individual buildings' operations using non-linear programming, thereby realizing the collaborations. For validation, the proposed collaborative demand response control is compared with a game-theory based non-collaborative demand response control. The developed control effectively reduces the cluster-level peak energy exchanges and electricity bills by 18% and 45.2%, respectively, with significant computational load reduction. This study will provide the decision makers a computation-efficient demand response control of nearly zero energy buildings which enables full collaborations and thus helps improve the performances.
•Develop a collaborative control for zero energy building cluster level performance improvements.•Consider two-way information exchanges between the power grid and end-use buildings.•Compare the developed control with a non-collaborative demand response control.•Analyze performance improvements in aspects of economic cost, grid friendliness and computation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Graft modified flocculants have recently received increasing attention in the field of water treatment as they have the combinative advantages of synthetic and natural polymeric flocculants. In this ...work, surface-active monomer benzyl(methacryloyloxyethyl)dimethylammonium chloride (BMDAC) was selected to graft on dextran (DX) with high molecular weight (10.3 × 106 g/mol) produced through enzyme-catalyzed process in order to remove dissolved dyes from wastewater. The flocculant (DAB) was fabricated by ultrasound initiated polymerization technique, and the structure characterization of FTIR, 1H/12C NMR, XRD and XPS spectrum confirmed the successful grafting. Then the Congo red (CR) removal efficiency by DAB was optimized based on the flocculation conditions, including wastewater initial pH, flocculant dosage and initial dye concentration. The effect of suspended solids on the removal of dyes was evaluated in kaolin-CR simulated wastewater. The results indicated that the optimal removal efficiency of CR was 68.1% and 88.2% in single CR and kaolin-CR flocculation system, respectively. The improvement of removal efficiency was attributed to the fact that partial CR molecules were adsorbed onto kaolin particles before flocculation, and were synergistically flocculated accompanied by kaolin particles. Finally, the flocculation mechanism was discussed by a detailed investigation of the zeta potentials, FTIR and XPS spectra of flocs, which can provide important reference for optimizing the flocculation conditions and designing novel high-performance flocculants.
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•A dextran-based flocculant DAB was designed and prepared by ultrasound initiated polymerization technique.•Flocculation of dye wastewater was studied.•The high flocculation performance of DAB is due to structural advantages.•The existence of suspended solids markedly improved the removal of dyes.•Zeta potentials, FTIR and XPS spectra of flocs were measured for mechanism study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Little study reviews the load shifting control using different facilities.•This study reviews load shifting control using building thermal mass.•This study reviews load shifting control using ...thermal energy storage systems.•This study reviews load shifting control using phase change material.•Efforts for developing more applicable load shifting control are addressed.
For decades, load shifting control, one of most effective peak demand management methods, has attracted increasing attentions from both researchers and engineers. Different load shifting control strategies have been developed when diverse cold thermal energy storage facilities are used in commercial buildings. The facilities include building thermal mass (BTM), thermal energy storage system (TES) and phase change material (PCM). Little study has systematically reviewed these load shifting control strategies and therefore this study presents a comprehensive review of peak load shifting control strategies using these thermal energy storage facilities in commercial buildings. The research and applications of the load shifting control strategies are presented and discussed. The further efforts needed for developing more applicable load shifting control strategies using the facilities are also addressed.
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GEOZS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK
Air pollution exposure is associated with a range of adverse health impacts. Knowledge of the chemical components and sources of air pollution most responsible for these health effects could lead to ...an improved understanding of the mechanisms of such effects and more targeted risk reduction strategies. We measured daily ambient fine particulate matter (<2.5 μm in aerodynamic diameter; PM2.5) for 2 months in peri-urban and central Beijing, and assessed the contribution of its chemical components to the oxidative potential of ambient air pollution using the dithiothreitol (DTT) assay. The composition data were applied to a multivariate source apportionment model to determine the PM contributions of six sources or factors: a zinc factor, an aluminum factor, a lead point factor, a secondary source (e.g., SO4 2–, NO3 2–), an iron source, and a soil dust source. Finally, we assessed the relationship between reactive oxygen species (ROS) activity-related PM sources and inflammatory responses in human bronchial epithelial cells. In peri-urban Beijing, the soil dust source accounted for the largest fraction (47%) of measured ROS variability. In central Beijing, a secondary source explained the greatest fraction (29%) of measured ROS variability. The ROS activities of PM collected in central Beijing were exponentially associated with in vivo inflammatory responses in epithelial cells (R 2 = 0.65–0.89). We also observed a high correlation between three ROS-related PM sources (a lead point factor, a zinc factor, and a secondary source) and expression of an inflammatory marker (r = 0.45–0.80). Our results suggest large differences in the contribution of different PM sources to ROS variability at the central versus peri-urban study sites in Beijing and that secondary sources may play an important role in PM2.5-related oxidative potential and inflammatory health impacts.
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IJS, KILJ, NUK, PNG, UL, UM
•Interactive building power demand management strategy for integrating commercial buildings into smart grid.•Quantify demand and demand alteration characteristics of commercial buildings to ...facilitate the smart grid optimization.•Building thermal storage model is developed for predicting power demand alteration potential.•Commercial buildings can contribute significantly and effectively in grid power demand management.
With increasing use and integration of renewable energies, power imbalance between supply and demand sides has become one of the most critical issues in developing smart grid. As the major power consumers at demand side, buildings can actually perform as distributed thermal storages to help relieving power imbalance of a grid. However, power demand alteration potentials of buildings and energy information of grids might not be effectively predicted and communicated for interaction and optimization. This paper presents an interactive building power demand management strategy for the interaction of commercial buildings with a smart grid and facilitating the grid optimization. A simplified building thermal storage model is developed for predicting and characterizing power demand alteration potentials of individual buildings together with a model for predicting the normal power demand profiles of buildings. The simulation test results show that commercial buildings can contribute significantly and effectively in power demand management or alterations with building power demand characteristics identified properly.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract The targeted delivery of anticancer agents is a promising field in anticancer therapy. Mesenchymal stem cells (MSCs) have inherent tumor-tropic and migratory properties, which allow them to ...serve as vehicles for targeted drug delivery systems for isolated tumors and metastatic diseases. MSCs have been successfully studied and discussed as a vehicle for cancer gene therapy. However, MSCs have not yet been discussed adequately as a potential vehicle for traditional anticancer drugs. In this review, we will examine the potential of MSCs as a targeted-delivery vehicle for anticancer drug-loaded nanoparticles (NPs), summarize various challenges, and discuss possible solutions for these challenges. From the Clinical Editor In this review, the feasibility of mesenchymal stem cell-based targeted delivery of anticancer agents is discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK