Spatial Process of Green Infrastructure Changes Associated with Rapid Urbanization in Shenzhen,China

Through a case study of Shenzhen City,China,this study focused on a quantitative method for analyzing the spatial processes involved in green infrastructure changes associated with rapid urbanization.Based on RS,GIS and SPSS statistics software,the approach includes selection of the square analysis units and representative landscape metrics,quantification of the change types of landscape metrics in all analysis units through two indices and hierarchical cluster analysis of the above analysis units with different landscape metric change types(i.e.spatial attributes).The analyses verify that there is a significant sequence of continuous changes in green infrastructure in Shenzhen.They are the perforation,the segmentation,the fragmentation,the evanescence and the filling-in processes,which have a good spatio-temporal correspondence with urbanization and reflect the synthetic influence of urban planning,government policies and landforms.Compared with other studies on quantifying the spatial pattern,this study provides an alternative probe into linking the spatial pattern to spatial processes and the corresponding ecological processes in the future.These spatio-temporal processes offer many opportunities for identifying,protecting and restoring key elements in an urban green infrastructure network for areas in the early stages of urbanization or for non-urbanized areas.

Quantitative Analysis of the Outdoor Thermal Comfort in the Hot and Humid Summertime of Shenzhen, China

Outdoor thermal comfort has always been a major issue due to its irreplaceable role in maintaining good health and energy use. Thus,quantitative analysis of outdoor thermal comfort and discussions on influential factors seem very necessary to achieve the climate-conscious urban design. Therefore,an outdoor thermal comfort questionnaire survey and the simultaneous field measurement were conducted in six different places during the hot and humid summertime in Shenzhen. The results show that the overall weather conditions during the investigation can be expressed with high temperature and high humidity with strong solar radiation. The micro-meteorological parameters of six test sites vary greatly due to their different regional spatial layouts.Moderate range of air temperature( Ta) is between 28 to 30 ℃ while that of relative humidity( RH) mainly concentrates in 60%-70% with the thermal sensation votes. The main influential factors impacting outdoor thermal comfort are obtained and Tahas the greatest effect. The overall thermal comfortable ranges in Shenzhen are expressed by the range of 28. 14-32. 83 ℃ of PET and 24. 74-30. 45 ℃ of SET*. With the correlation analysis between the characteristic parameters of regional spatial layout and thermal climate and thermal comfort,it reveals that increasing the coverage ratio of water and green space( S) helps lower Taand increase RH. The global solar radiation( G) has a significant negative correlation with the height of buildings( H) and a positive correlation with sky view factor( SVF). Overall,reasonable configuration of the regional spatial layout contributes to providing a thermal comfortable environment.

Layout Optimization of Riverside Residential Area Based on Thermal Comfort: A Case Study of Nanhua Village, Shenzhen

Based on the previous researches on building layout with thermal comfort, this paper Stud Shenzhen Nanhua Village to explore the way of using building layout to change thermal environment of riverfront residential areas. The results showed that a more comfortable outdoor thermal environment could be obtained by applying proper building layouts favorable for the thermal comfort of the Nanhua Village. It proves again that efficient and feasible building layout, which is suitable for a river microclimate, is important in improving thermal comfort of a riverside residential area. The study also provides a good example for the future architectural designs of a riverside residential area for obtaining thermal comfort.

Quantitative Analysis of Spatial Vitality of Urban Built-up Area: A Case Study of Shenzhen

As an important goal of urban design research,the evaluation of urban spatial vitality has been widely concerned.Taking Shenzhen as an example,the urban built-up area of Shenzhen was identifi ed using improved DENsi-Graph analysis,from the perspective of quantifi cation of urban spatial morphological features.The accessibility of urban streets,degree of construction and architectural form,and degree of functional mixing were quantitatively analyzed through space syntax,space matrix and mixeduse index(MXI),and the spatial vitality of urban built-up area was evaluated.Research results demonstrated that the improved Densi-Graph analysis could better identify the built-up area of Shenzhen,and the overall classifi cation accuracy was 0.810.The analysis results of spatial vitality showed that the urban spatial vitality in Shenzhen urban built-up area was well created.The street accessibility of Shenzhen generally hindered the creation of urban vitality;the spatial matrix value in the north of Shenzhen urban built-up area was lower;and the MXI of most areas within the study area was above the medium.

Factors Affecting the Rent of Shops in Commercial Complexes: A Case Study of Shenzhen Shekou Sea World

The rent of shops in commercial complex reflects consumers’ preferences to some extent, and provides references for urban planning and the construction and operation of commercial complex. In this paper, Sea World Commercial Complex in Nanshan District of Shenzhen City is taken as the research object, and correlation and variability analysis on 41 groups of shop data are conducted. It is found that rent of shops in the same commercial complex is affected by location, visibility and area of outdoor stall, while the influence of shop area on rent is not obvious. Additionally, there is no significant correlation between the accessibility to traffic stations and the rent of shops in pedestrian business district.

Urban Morphology of Urban Village: A Case Study of Dafen Oil Painting Village in Shenzhen

Dafen Oil Painting Village, the largest oil painting village in current China, takes cultural industries like creation and wholesale of oil paintings as the pillar. As one of the urban villages in Shenzhen, Dafen Village not only has the common characteristics of urban morphology as ordinary urban villages, but also has something unique. In this paper, study of the urban morphology of Dafen Oil Painting Village is mainly from 3 aspects: firstly, the formation of street space in Dafen Village; secondly, analysis of the status of urban morphology of Dafen Village; thirdly, the plane layout and public space of Dafen Village. In the end, this paper put forward some suggestions about the future development of urban morphology and space layout in Dafen Village.

Immigrant Urban Housing and Socio-spatial Structure and Its Formation Mechanism:A Case Study of Shenzhen

Urban housing and socio-spatial attribute indicators are selected to identify housing and socio-spatial structure and its formation mechanism of Shenzhen.The following are the main conclusions.①Principal factors influencing the social area of Shenzhen include housing facilities,highly educated immigrants,migrant population,family structure,housing area and economic income level.②The socio-spatial structure which composed by six types of social areas shows obvious differentiation based on population mobility,housing,educational level and economic income level,forming a typical dual pattern of "urban society_-migrant worker society".③The formation of socio-spatial structure in Shenzhen results from natural conditions,economic development and institutional factors like the establishment of special economic zone,land system reform and urban planning.

Measurement and Characteristics of Employment Centers in Shenzhen:A Study Using Enterprise Survey Data in 2017

In the formation process of megacities,urban population is constantly gathering from other cities to large and medium-sized cities,and from the periphery of the city to the center of the city,inducing traffic congestion,overload of main center,reduction of space efficiency,and other major urban diseases.Multi-center urban spatial structure is an effective way to solve the above negative externalities.It is helpful to evaluate the efficiency of the existing industrial distribution structure in the cities and make a reasonable estimate of the future enterprise growth by clarifying the interactive relationship between the development process of a city and the change of the employment center.Based on survey data of Shenzhen "Four Up-scale Enterprises" in 2017,threshold method is used to identify the existing employment centers of Shenzhen,and describe the characteristics of each employment center.Combining calculation of industry location entropy,below conclusions are obtained:①the double main centers (Futian-Luohu center and Nanshan center) in Shenzhen are obvious,and the weak multi-center has initially formed;②the development of the industry is relatively balanced in Futian-Luohu center,and Nanshan center has absolute advantage in information technology industry;③the employment centers outside the original special economic zone are mainly manufacturing industries,showing a highly specialized trend of industries,and cultivation of service industries is insufficient.

A carbon-intensity based carbon allowance allocation scheme among enterprises in Shenzhen

On October 29, 2011, a number of cities and provinces in China were chosen to host pilot locations for carbon emissions trading systems. Before a carbon trading market can be functional, carbon emission allowances need to be allocated. This makes the carbon emissions allowance allocation scheme crucially important as it goes a long way in deciding the effi ciency and fairness of the carbon cap-andtrade market. Although it has been proved that allocation by auction is the most effective way, Shenzhen city as one of the trading pilots will allocate carbon allowances free of charge at the initial stage. The European Union's(EU) free allocation system, a product-based benchmark scheme for the manufacturing industry implement in 2013, is not feasible for Shenzhen due to the lack of data at a product level. Therefore the target of this paper is to explore a new allocation scheme with the data at a fi rm level other than the grandfathering scheme to fi ll the gap. In this paper, a carbon intensity based allocation scheme is developed by using the Boltzmann distribution and Gail- Shapley game. In the fi nal part of the report, fi rm level data from 2010 to 2011 of fi rms in Shenzhen, China are used to verify the effect and fi tness of the allocation scheme.

Reference Research of the Public Housing Policies of the United States and Singapore for Improving the Diversification of Shenzhen's Security House Location

In recent years,Shenzhen's housing prices are very high,ranking top 3 in China,and the purchasing power of ordinary residents has been seriously insufficient,leading to increase in demand for security housing.At present,Shenzhen's security housing projects are concentrated in areas outside the former Special Economic Zones,such as Pingshan,Longgang and Longhua.The houses in Luohu,Futian and Nanshan districts,where obtaining housing is more difficult and the intention of living is the most concentrated are scarce.The community distance is too long for most commuters inside customs.In terms of spatial distribution,the structural contradiction between the supply and demand of security housing has become increasingly prominent.In this paper,the public housing policies in the United States and Singapore were studied,and their reference to the diversification of Shenzhen's security housing location was analyzed.In addition,a feasible housing policy was proposed for Shenzhen.

Design of the Three-Dimensional Transportation System in Commercial Districts Against the Background of Urban Renewal:A Case Study of Shangbu District in Shenzhen

In this paper,Shangbu district,Shenzhen was taken for example to study the design of the three-dimensional transportation system in commercial districts against the background of urban renewal,so as to provide references for solving serious traffic problems in old urban industrial areas.Shangbu district adopted a diversified development model to ensure the appropriate spatial scale and constructed a three-dimensional transportation system concerning the underground,ground,and overground planes to guarantee the coexistence of people,goods,and vehicles.

Andrias davidianus bone peptides alleviates hyperuricemia-induced kidney damage in vitro and in vivo

Hyperuricemia(HUA)is a vital risk factor for chronic kidney diseases(CKD)and development of functional foods capable of protecting CKD is of importance.This paper aimed to explore the amelioration effects and mechanism of Andrias davidianus bone peptides(ADBP)on HUA-induced kidney damage.In the present study,we generated the standard ADBP which contained high hydrophobic amino acid and low molecular peptide contents.In vitro results found that ADBP protected uric acid(UA)-induced HK-2 cells from damage by modulating urate transporters and antioxidant defense.In vivo results indicated that ADBP effectively ameliorated renal injury in HUA-induced CKD mice,evidenced by a remarkable decrease in serum UA,creatinine and blood urea nitrogen,improving kidney UA excretion,antioxidant defense and histological kidney deterioration.Metabolomic analysis highlighted 14 metabolites that could be selected as potential biomarkers and attributed to the amelioration effects of ADBP on CKD mice kidney dysfunction.Intriguingly,ADBP restored the gut microbiome homeostasis in CKD mice,especially with respect to the elevated helpful microbial abundance,and the decreased harmful bacterial abundance.This study demonstrated that ADBP displayed great nephroprotective effects,and has great promise as a food or functional food ingredient for the prevention and treatment of HUA-induced CKD.

Label-free in-vivo classi-cation and tracking of red blood cells and platelets using Dynamic-YOLOv4 network

In-vivo flow cytometry is a noninvasive real-time diagnostic technique that facilitates continuous monitoring of cells without perturbing their natural biological environment,which renders it a valuable tool for both scientific research and clinical applications.However,the conventional approach for improving classification accuracy often involves labeling cells with fluorescence,which can lead to potential phototoxicity.This study proposes a label-free in-vivo flow cytometry technique,called dynamic YOLOv4(D-YOLOv4),which improves classification accuracy by integrating absorption intensity fluctuation modulation(AIFM)into YOLOv4 to demodulate the temporal features of moving red blood cells(RBCs)and platelets.Using zebrafish as an experimental model,the D-YOLOv4 method achieved average precisions(APs)of 0.90 for RBCs and 0.64 for thrombocytes(similar to platelets in mammals),resulting in an overall AP of 0.77.These scores notably surpass those attained by alternative network models,thereby demonstrating that the combination of physical models with neural networks provides an innovative approach toward developing label-free in-vivoflow cytometry,which holds promise for diverse in-vivo cell classification applications.

Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity

Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system.

An aqueous magnesium-ion hybrid supercapacitor operated at-50℃

The recent advances in aqueous magnesium-ion hybrid supercapacitor(MHSC)have attracted great attention as it brings together the benefits of high energy density,high power density,and synchronously addresses cost and safety issues.However,the freeze of aqueous electrolytes discourages aqueous MHSC from operating at low-temperature conditions.Here,a low-concentration aqueous solution of 4 mol L^(-1) Mg(ClO_(4))_(2) is devised for its low freezing point(-67℃)and ultra-high ionic conductivity(3.37 mS cm^(-1) at-50℃).Both physical characterizations and computational simulations revealed that the Mg(ClO_(4))_(2) can effectively disrupt the original hydrogen bond network among water molecules via transmuting the electrolyte structure,thus yielding a low freezing point.Thus,the Mg(ClO_(4))_(2) electrolytes endue aqueous MHSC with a wider temperature operation range(-50℃–25℃)and a higher energy density of 103.9 Wh kg^(-1) at 3.68 kW kg^(-1) over commonly used magnesium salts(i.e.,MgSO_(4) and Mg(NO_(3))_(2))electrolytes.Furthermore,a quasi-solid-state MHSC based on polyacrylamide-based hydrogel electrolyte holds superior low-temperature performance,excellentflexibility,and high safety.This work pioneers a convenient,cheap,and eco-friendly tactic to procure low-temperature aqueous magnesium-ion energy storage device.

Audio-visual keyword transformer for unconstrained sentence-level keyword spotting

As one of the most effective methods to improve the accuracy and robustness of speech tasks,the audio-visual fusion approach has recently been introduced into the field of Keyword Spotting(KWS).However,existing audio-visual keyword spotting models are limited to detecting isolated words,while keyword spotting for unconstrained speech is still a challenging problem.To this end,an Audio-Visual Keyword Transformer(AVKT)network is proposed to spot keywords in unconstrained video clips.The authors present a transformer classifier with learnable CLS tokens to extract distinctive keyword features from the variable-length audio and visual inputs.The outputs of audio and visual branches are combined in a decision fusion module.As humans can easily notice whether a keyword appears in a sentence or not,our AVKT network can detect whether a video clip with a spoken sentence contains a pre-specified keyword.Moreover,the position of the keyword is localised in the attention map without additional position labels.Exper-imental results on the LRS2-KWS dataset and our newly collected PKU-KWS dataset show that the accuracy of AVKT exceeded 99%in clean scenes and 85%in extremely noisy conditions.The code is available at https://github.com/jialeren/AVKT.

Recent progress about transmission electron microscopy characterizations on lithium-ion batteries

With the rapid development of portable electronics,new energy vehicles,and smart grids,ion batteries are becoming one of the most widely used energy storage devices,while the safety concern of ion batteries has always been an urgent problem to be solved.To develop a safety-guaranteed battery,the characterization of the internal structure is indispensable,where electron microscopy plays a crucial role.Based on this,this paper summarizes the application of transmission electron microscopy(TEM)in battery safety,further concludes and analyzes the aspects of dendrite growth and solid electrolyte interface(SEI)formation that affect the safety of ion batteries,and emphasizes the importance of electron microscopy in battery safety research and the potential of these techniques to promote the future development of this field.These advanced electron microscopy techniques and their prospects are also discussed.

A large-scale cold plasma jet: generation mechanism and application effect

Atmospheric pressure cold plasma jets(APCPJs) typically exhibit a slender, conical structure,which imposes limitations on their application for surface modification due to the restricted treatment area. In this paper, we introduce a novel plasma jet morphology known as the large-scale cold plasma jet(LSCPJ), characterized by the presence of both a central conical plasma jet and a peripheral trumpet-like diffuse plasma jet. The experimental investigations have identified the factors influencing the conical and the trumpet-like diffuse plasma jet, and theoretical simulations have shed light on the role of the flow field and the electric field in shaping the formation of the LSCPJ. It is proved that, under conditions of elevated helium concentration, the distributions of impurity gas particles and the electric field jointly determine the plasma jet’s morphology. High-speed ICCD camera images confirm the dynamic behavior of plasma bullets in LSCPJ, which is consistent with the theoretical analysis. Finally, it is demonstrated that when applied to the surface treatment of silicone rubber, LSCPJ can achieve a treatment area over 28 times larger than that of APCPJ under equivalent conditions. This paper uncovers the crucial role of impurity gases and electric fields in shaping plasma jet morphology and opens up the possibility of efficiently diversifying plasma jet generation effects through external electromagnetic fields. These insights hold the promise of reducing the generation cost of plasma jets and expanding their applications across various industrial sectors.

Multiple-dimensioned defect engineering for graphite felt electrode of vanadium redox flow battery

The scarcity of wettability,insufficient active sites,and low surface area of graphite felt(GF)have long been suppressing the performance of vanadium redox flow batteries(VRFBs).Herein,an ultra-homogeneous multipledimensioned defect,including nano-scale etching and atomic-scale N,O codoping,was used to modify GF by the molten salt system.NH_(4)Cl and KClO_(3) were added simultaneously to the system to obtain porous N/O co-doped electrode(GF/ON),where KClO_(3) was used to ultra-homogeneously etch,and O-functionalize electrode,and NH4Cl was used as N dopant,respectively.GF/ON presents better electrochemical catalysis for VO_(2)+/VO_(2)+ and V3+/V2+ reactions than only O-functionalized electrodes(GF/O)and GF.The enhanced electrochemical properties are attributed to an increase in active sites,surface area,and wettability,as well as the synergistic effect of N and O,which is also supported by the density functional theory calculations.Further,the cell using GF/ON shows higher discharge capacity,energy efficiency,and stability for cycling performance than the pristine cell at 140 mA cm^(−2) for 200 cycles.Moreover,the energy efficiency of the modified cell is increased by 9.7% from 55.2% for the pristine cell at 260 mA cm^(−2).Such an ultra-homogeneous etching with N and O co-doping through“boiling”molten salt medium provides an effective and practical application potential way to prepare superior electrodes for VRFB.

Call for knowledge systematization:An example from lithium ion batteries recycling

Scientific research is one of the primary ways to drive human civilization forward.Countless research institutions and researchers worldwide are dedicated to exploring the unknown,resulting in a flood of research findings[1].For instance,Web of Science alone collects over 10,000 academic papers on a daily basis.While each research field typically has around 10%of review articles,these mainly focus on a limited portion of the subject,failing to provide a comprehensive and real-time updated overview.As a result,researchers or students in a particular field may spend several months,or even longer,comprehending the state of research that has developed over just a few years.The lack of systematic background often leads to redundant or similar studies,which is highly detrimental to the progress of science and technology.