Review of Typical Municipal Solid Waste Disposal Status and Energy Technology

AbstractThe physical and chemical components of urban domestic waste, medical waste and electronic waste are introduced, the advantages and disadvantages of the existing processing methods are pointed out. Considering the higher content of organic and metal of these municipal solid wastes, pyrolysis technology is a suitable method to make them harmless, reduced, reusable and being available energy

Analysis on limitation of Using Solar Fraction Ratio as Solar Hot Water System Design and Evaluation Index

AbstractSolar fraction ratio is a key index and reference of solar hot water system design, andis also a key factor to evaluate solar hot water system according to Evaluation Standard for Application of Renewable Energy in Buildings in China. By analyzing relevant inspection data of actual projects, it was found that using solar fraction ratio to evaluate the actual running systems has certain limitation, which cannot reasonably reflect the actual supplementation of conventional energy, especially with the residential buildings applying central solar hot water system. Based on the total energy consumption control concept raised by government during the Twelfth Five-Year Plan period, the actual supplementation level of conventional energy should be used as a factor to evaluate solar hot water system. This study will analyze the limitation of solar fraction ratio in design and evaluation, and propose corresponding ideas of solution as references for relevant design and evaluation professionals

Exploring spatial association between residential and commercial urban spaces: A machine learning approach using taxi trajectory data

Human mobility datasets, such as traffic flow data, reveal the connections between urban spaces. A novel framework is proposed to explore the spatial association between urban commercial and residential spaces via consumption travel flows in Shanghai. A social network analysis and a community detection method are employed using taxi trajectory data during the daytime to validate the framework. The machine learning-based approach, such as the community detection method, can overcome the limitation regarding spatial uncertainty and spatial effects. The empirical findings suggest that people's commercial activities are sensitive to the power of accessible commercial centers and travel distances. The high-level commercial centers would contribute to the monocentric structure in the outer urban region based on consumption flows. In the central urban region, increasing the number of high-level commercial centers and making the powers of commercial centers hierarchical can contribute to a polycentric mobility pattern of people's consumption. This research contributes to the literature by providing a novel framework to model, analyze and visualize people's mobility based on the trajectory big data, which is promising in future urban research

Exploring spatial association between residential and commercial urban spaces: A machine learning approach using taxi trajectory data

Human mobility datasets, such as traffic flow data, reveal the connections between urban spaces. A novel framework is proposed to explore the spatial association between urban commercial and residential spaces via consumption travel flows in Shanghai. A social network analysis and a community detection method are employed using taxi trajectory data during the daytime to validate the framework. The machine learning-based approach, such as the community detection method, can overcome the limitation regarding spatial uncertainty and spatial effects. The empirical findings suggest that people's commercial activities are sensitive to the power of accessible commercial centers and travel distances. The high-level commercial centers would contribute to the monocentric structure in the outer urban region based on consumption flows. In the central urban region, increasing the number of high-level commercial centers and making the powers of commercial centers hierarchical can contribute to a polycentric mobility pattern of people's consumption. This research contributes to the literature by providing a novel framework to model, analyze and visualize people's mobility based on the trajectory big data, which is promising in future urban research

Study on Synthesis, Characterization and in Vitro Activity of Sweet Corncob Polysaccharide Nano-Silver

Silver nanoparticles (AgNPs) are widely used in the field of biomedicine. However, the synthesis of AgNPs by traditional physical and chemical methods has problems such as pollution, product toxicity, and time-consuming. Therefore, it is extremely important to explore the preparation of AgNPs. Silver nanoparticles (AgNPs) of sweet corncob polysaccharide (SCP-AgNPs) were successfully synthesized by green method using sweet corncob polysaccharide (SCP) as raw material and the reaction conditions were optimized. The generated AgNPs were characterized by transmission electron microscopy (TEM), X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, and their antioxidant and anti-diabetic abilities in vitro were investigated. The results showed that the optimum reaction conditions of SCP-AgNPs were as follows: The concentration of silver nitrate in the solution was 0.75×10−3 mol/L, the pH was 10.0, and the reaction time was 80 min. The prepared SCP-AgNPs were spherical with an average particle size of 13.5 nm. The structure showed a face-centered cubic crystal structure, and Ag was determined to be Ag0 state. The synthesized SCP-AgNPs had strong free radical scavenging effect in vitro. At the same time, SCP-AgNPs had a good inhibitory effect on the activity of α-glucosidase and α-amylase. SCP-AgNPs has a significant inhibitory effect on key enzymes of diabetes and has potential anti-diabetic activity. It is a nano-drug suitable for nano-biomedical applications and will be widely used in food processing, medicine and other fields in the future

Maneuvering Decision Making Based on Cloud Modeling Algorithm for UAV Evasion–Pursuit Game

When facing problems in the aerial pursuit game, most of the current unmanned aerial vehicles (UAVs) have good maneuverability performance, but it is difficult to utilize the overload maneuverability of UAVs properly; further, UAVs tend to be more costly, and it is often difficult to effectively prevent the enemy from reaching the tailgating position behind the UAV in the aerial pursuit game. Therefore, there is a pressing need for a maneuvering algorithm that can effectively allow a UAV to quickly protect itself in a disadvantageous position, stably and effectively select a maneuver with the maneuvering algorithm, and stably and effectively establish an advantage by moving to an advantageous position. Therefore, this paper establishes a cloud model-based UAV-maneuvering aerial pursuit decision-making model based on pursuit-and-evasion game positions. Based on the evaluation of the latter, when the UAV is at a disadvantage, we use the constructed defensive maneuver expert pool to abandon the disadvantageous position. When the UAV is at an advantage, we use cloud model-based pursuit-and-evasion game maneuvering decision making to establish an advantageous position. According to the results of the simulation examples, the maneuvering decision-making method designed in this paper confirms that the UAV can quickly abandon its position and establish an advantage in case of parity or disadvantage and that it can also stably establish a tail-chasing position in case of advantage

Inhibitory Effect of Selenium Sweet Corncob Polysaccharide on Non-Enzymatic Glycosylation

A selenized polysaccharide (Se-SCP) with selenium content of (7.19±0.067) mg/g was synthesized by imidazole-mediated method using sweet corncob polysaccharide (SCP) as raw material. In order to explore the inhibitory effect of Se-SCP on non-enzymatic glycosylation reaction, fructose and bovine serum albumin (BSA) were selected as substrates to establish albumin/fructose simulation system. Fructosamine→α-dicarbonyl compounds→advanced glycation end products (AGEs), the three characteristic products in the non-enzymatic glycosylation process, were determined and analyzed by transmission electron microscopy (TEM) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The effects of protopolysaccharides and selenium polysaccharides on the non-enzymatic glycosylation process were compared and analyzed in terms of microstructure. The results showed that Se-SCP had different degrees of inhibition on the three stages of protein non-enzymatic glycosylation process, and the inhibition rates of characteristic products in non-enzymatic glycosylation process reached 89.5%, 74.9% and 71.7%, respectively. In terms of inhibiting protein cross-linking structure, compared with the SCP group, the texture of Se-SCP was relatively clear, the structural density was small, and the inhibition effect was obvious. The results of SDS-PAGE showed that Se-SCP reduced the formation of high molecular weight cross-linked protein induced by fructose, and the effect of Se-SCP was better, which was similar to that of positive drug. In summary, Se-SCP has good anti-nonenzymatic glycation activity and has great potential in inhibiting diabetes and its complications

Study on Demand-side Design Parameters of Solar Domestic Hot Water System in Residential Buildings

AbstractSolar domestic hot water system is widely used and developing fast in recent years in China. However many problems occur at the same time, for example more energy consumption by circulation pump, water reheating, long investment payback period, and etc. Through analyzing the field-testing data of projects and investigating of different residential consumers, it was found that compared to actual hot water consumption the solar domestic hot water systems were generally designed too large in capacity, which means the designed hot water demand is much greater than actual user consumption. This study compared different specifications and recommended design parameters value of hot water related standards, and analyzed the calculation methodology and design parameter ofhot water quota. Finally problems in the system design are summarized and suggestions are proposed for designers and different stakeholders

Identify social and job disparities in the relationship between job‐housing balance and urban commuting using Baidu trajectory big data

Abstract The job‐housing relationship is a well‐documented topic in urban and economic geography literature, but the disparities in job‐housing relationships across workers' sociodemographic statuses have yet to be fully explored. This study utilizes a Baidu trajectory dataset and spatial analysis tools to examine job‐housing relationships in Zhuhai, China, taking into account disparities in workers' socioeconomic status and job types. Origin–destination analysis indicates that job‐housing relationships for commercial and public service sectors are balanced in the urban core, whereas, for the secondary sector, the relationship is more balanced in the suburban area compared to the central urban area. Network analysis further reveals the presence of self‐contained communities for the secondary sector in peripheral areas. We find that high‐income workers in the secondary sector experience longer commuting distances, in contrast to their counterparts in the commercial and public service sectors. These insights underscore the significance of considering workers' skills in urban and economic planning