Cluster Mode Research Articles

Evaluation and analysis of leading position in hydrogen fuel cell vehicle innovation network and the influential factors: a case of patent citations in China.

Hydrogen fuel cell vehicle industry is of great significance for China to achieve carbon neutrality by 2060 and enhance the international competitiveness in the new energy vehicle industry. We propose a framework to evaluate the leading position in the innovation network of hydrogen fuel cell vehicles and analyze the influential factors of the leading position. First, we construct China's hydrogen fuel cell vehicle innovation network and its two sub-networks through 3528 patents registered in China and applied by 254 Chinese and foreign innovators. Second, the positions of Chinese and foreign innovators in the network are evaluated. Last, the influential factors of the leading position are tested through regression analysis. The main results show that (1) China has formed a hub-and-spoke mode of innovation cluster in hydrogen fuel cell vehicle innovation network, but the inter-provincial innovation cooperation has not been formed in the industrial chain. (2) Universities and research institutes are important innovators in China's hydrogen fuel cell vehicle innovation network. Firms obtain knowledge through collaboration with them, which form an industry-university-research cooperation mode. (3) The number of Chinese leaders in hydrogen fuel cell vehicle network is increasing. Foreign innovators occupy the leading position in fuel cell sub-network, while Chinese innovators are the leaders in hydrogen infrastructure sub-network. (4) The leading position of Chinese innovators in hydrogen infrastructure sub-network is promoted by the patent applications of the universities, the development of equipment manufacturing, the government subsidies, and the competition of electric vehicles, while they are hindered by the scale of traditional automobile industry.

Market Mechanisms and Trading in Microgrid Local Electricity Markets: A Comprehensive Review

Electricity generation using distributed renewable energy systems is becoming increasingly common due to the significant increase in energy demand and the high operation of conventional power systems with fossil fuels. The introduction of distributed renewable energy systems in the electric grid is crucial for delivering future zero-emissions energy systems and is cost-effective for promoting and facilitating large-scale generation for prosumers. However, these deployments are forcing changes in traditional energy markets, with growing attention given to transactive energy networks that enable energy trading between prosumers and consumers for more significant benefits in the cluster mode. This change raises operational and market challenges. In recent years, extensive research has been conducted on developing different local energy market models that enable energy trading and provide the opportunity to minimize the operational costs of the distributed energy resources by promoting localized market management. Local energy markets provide a stepping stone toward fully transactive energy systems that bring adequate flexibility by reducing users’ demand and reflecting the energy price in the grid. Designing a stable regulatory framework for local electricity markets is one of the major concerns in the electricity market regulation policies for the efficient and reliable delivery of electric power, maximizing social welfare, and decreasing electric infrastructure expenditure. This depends on the changing needs of the power system, objectives, and constraints. Generally, the optimal design of the local market requires both short-term efficiencies in the optimal operation of the distributed energy resources and long-term efficiency investment for high quality. In this paper, a comprehensive literature review of the main layers of microgrids is introduced, highlighting the role of the market layer. Critical aspects of the energy market are systematically presented and discussed, including market design, market mechanism, market player, and pricing mechanism. We also intend to investigate the role and application of distributed ledger technologies in energy trading. In the end, we illuminate the mathematical foundation of objective functions, optimization approaches, and constraints in the energy market, along with a brief overview of the solver tools to formulate and solve the optimization problem.

Ultra Short-Term Power Load Forecasting Based on Similar Day Clustering and Ensemble Empirical Mode Decomposition

With the increasing demand of the power industry for load forecasting, improving the accuracy of power load forecasting has become increasingly important. In this paper, we propose an ultra short-term power load forecasting method based on similar day clustering and EEMD (Ensemble Empirical Mode Decomposition). In detail, the K-means clustering algorithm was utilized to divide the historical data into different clusters. Through EEMD, the load data of each cluster were decomposed into several sub-sequences with different time scales. The LSTNet (Long- and Short-term Time-series Network) was adopted as the load forecasting model for these sub-sequences. The forecast results for different sub-sequences were combined as the expected result. The proposed method predicts the load in the next 4 h with an interval of 15 min. The experimental results show that the proposed method obtains higher prediction accuracy than other comparable forecasting models.

Tellurium Nanosphere/Hematite Hybrid Thin Films with Enhanced Light Absorption for Efficient Photocatalysis

As a semimetal, tellurium (Te) shows metallic and dielectric properties in the UV and visible ranges, respectively, and has potential as a broad-band light absorber. In this paper, plasmonic–semiconductor hybrid nanoscale films consisting of Fe2O3 thin films and Te nanospheres are designed and demonstrated. Te clusters are proved to have an enhancement of the electric near-field in a broad UV–vis–NIR spectrum, which facilitates light absorption and charge separation in photoelectrocatalysis. The thickness of Fe2O3 films is adjusted from 22 to 137 nm. The photocurrent density enhancement factor of Te-modified films is 13 times higher than that of 22 nm Fe2O3 films. Particularly, a Te-decorated Fe2O3 ultrathin film exhibits photoelectrochemical activity comparable to that of bulk Fe2O3, suggesting significant near-field enhancement from plasmon modes of the Te clusters. It is found that the Te cluster decoration led to a significant decrease of the charge transfer resistance, demonstrating that the Te clusters could boost the formation rate and suppress the recombination rate of electron–hole pairs. The hybridization of Te nanoparticles with nanoscale semiconductor films represents an efficient way to enhance the solar energy conversion efficiency.

Spatio-temporal agglomeration and morphological causes of Shanghai catering clusters

This study employed the Gaussian Mixture Model to identify the location evolution and two-dimensional morphology of catering clusters in Shanghai in 2016, 2018 and 2020. We used the two-way fixed model to analyze the relationship between the location and type change of catering clusters and the other five land use types (17 types of POIs). The findings revealed that although restaurants follow the agglomeration mode under the principle of cumulative attraction, it is inconsistent with the rolling diffusion mode of traditional industrial clusters. Large clusters with obvious indigenous scale advantages evolve into more clusters with relative scale advantages and agglomeration forms relying on one or more buildings and spreading along the street. While the former has a more substantial economic contribution, the latter has stronger spatial expansion. The spatial combination of urban ring road expansion and residential land, land for commercial services, land for entertainment, and scenic spots determines the location selection and structural differences of catering clusters. Our findings can help Shanghai alleviate the siphoning effect in the central urban area.

Optical Breakdown on Clusters of Gas Nanobubbles in Water; Possible Applications in Laser Ophthalmology

Here we studied the regimes of optical breakdown in water, stimulated by nanosecond and picosecond laser pulses at a wavelength of 1064 nm. A distinctive feature of our theoretical model, confirmed in experiment, is that in our case the optical breakdown develops on heterogeneous centers-clusters of gas nanobubbles. To the best of our knowledge, this is the first study of the role of clusters of gas nanobubbles in the optical breakdown of liquids that are transparent to pump radiation. In the experiment described in this paper, it was found that when initially degassed water is saturated with dissolved air, the breakdown threshold decreases. A theoretical model describing this phenomenon is suggested. This model includes the development of an electron avalanche inside individual nanobubbles, followed by the stimulated optical coalescence of a nanobubble cluster. According to our estimates, this regime occurs at laser radiation intensities of about 106–107 W/cm2. It is important that at such low intensities the breakdown flash (the basic endpoint of optical breakdown) does not appear due to the deficit of input laser energy. We provide an experimental proof of the coalescence regime, stimulated by a laser pulse in nanosecond range. The experimental threshold of stimulated coalescence is in good agreement with the theoretical estimates. Since the stimulated optical coalescence mode occurs at very low laser intensities, its excitation does not result in mechanical side effects in eye tissues, i.e., a shock wave should not be excited. Note that shock wave always occurs during optical breakdown, which is traditionally excited at intensities of 1012 W/cm2. In our experiment, the generation of a shock wave at such pump intensities was also observed. Since, according to the estimates given in the article, the volume number density of nanobubble clusters in the intraocular fluid can reach 108 cm−3, the excitation of the stimulated optical coalescence mode of nanobubble clusters can be used in ophthalmic surgery, such as laser iridotomy.

Complex fracture propagation model and plugging timing optimization for temporary plugging fracturing in naturally fractured shale

In this paper, a viscoelasticity-plastic damage constitutive equation for naturally fractured shale is deduced, coupling nonlinear tensile-shear mixed fracture mode. Dynamic perforation-erosion on fluid re-distribution among multi-clusters are considered as well. DFN-FEM (discrete fracture network combined with finite element method) was developed to simulate the multi-cluster complex fractures propagation within temporary plugging fracturing (TPF). Numerical results are matched with field injection and micro-seismic monitoring data. Based on geomechanical characteristics of Weiyuan deep shale gas reservoir in Sichuan Basin, SW China, a multi-cluster complex fractures propagation model is built for TPF. To study complex fractures propagation and the permeability-enhanced region evolution, intersecting and competition mechanisms between the fractures before and after TPF treatment are revealed. Simulation results show that: fracture from middle cluster is restricted by the fractures from side-clusters, and side-clusters plugging is benefit for multi fractures propagation in uniformity; optimized TPF timing should be delayed within a higher density or strike of natural fractures; Within a reservoir-featured natural fractures distribution, optimized TPF timing for most clustered method is 2/3 of total fluid injection time as the optimal plugging time under different clustering modes.

Three-dimensional solid particle self-assembly in thermovibrational flow: The case with unidirectional temperature gradient and concurrent vibrations

As a follow-up to earlier work [Crewdson and Lappa, “Spatial and temporal evolution of three-dimensional thermovibrational convection in a cubic cavity with various thermal boundary conditions,” Phys. Fluids 34, 014108 (2022)], where the main focus was on the modes of convection in a three-dimensional cubic enclosure filled with a Pr = 7 liquid undergoing vibrations in a direction “parallel” to the imposed temperature gradient, the present study considers the modes of particle clustering, which occur when solid spheres, with density ratio ξ = 1.85 or 0.3 and Stokes number (St) between 0.5 and 3.5 × 10−5, are added to the fluid. Starting from a uniform distribution of solid particles and fluid in quiescent conditions, the governing equations for the involved phases are numerically solved in their complete, time-dependent, and non-linear form for a representative vibrational Rayleigh number (8.34 × 104), angular frequency Ω = 50, and non-dimensional acceleration amplitude (γ) spanning the interval 0.4 × 107 ≤ γ ≤ 3.4 × 107. It is shown that, while for relatively high values of St and/or γ, only degenerate states are obtained, where all particles collapse on planar structures, for intermediate values of such parameters, interesting (heretofore unseen) patterns are enabled. The hallmark of these phenomena is an endless squeezing and expansion of the particle formations along the direction of the temperature gradient. As confirmed by the numerical simulations, the underlying formation mechanisms rely on the combined action of the body force acting on particles due to their different densities with respect to the host fluid and the additional drag that is produced when the carrier thermovibrational flow enters a specific stage, known as “convective burst,” where the magnitude of the fluid velocity increases dramatically.

The management correlation between metabolic index, cardiovascular health, and diabetes combined with cardiovascular disease.

Cardiovascular disease (CVD) has become a major cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM). Although there is also evidence that multifactorial interventions to control blood glucose, blood pressure, and lipid profiles can reduce macrovascular complications and mortality in patients with T2DM, the link between these risk factors has not been established. On 10 December 2018, 1,920 people in four cities in Anhui Province were included. Latent category analysis (LCA) was used to explore the clustering mode of HRBs (health risk behaviors). The primary exposure was HRBs and exercise and diet interventions, and the primary outcome was CVD and other variables, including zMS, triglyceride-glucose index (TyG), TyG-WC (waist circumference), TyG-BMI, TG/HDL, and cardiovascular health (CVH). A multivariable logistic regression model was used to establish the relationship between HRBs, exercise, diet interventions, and CVD. Moderate analysis and mediation moderation analysis were employed by the PROCESS method to explore the relationship between these variables. Sensitivity analysis explored the robustness of the model. The mean age was 57.10 ± 10.0 years old. Overall, CVD affects approximately 19.9% of all persons with T2DM. Macrovascular complications of T2DM include coronary heart disease, myocardial infarction (MI), cardiac insufficiency, and cerebrovascular disease. Elderly age (χ 2 = 22.70), no occupation (χ 2 = 20.97), medium and high socioeconomic status (SES) (χ 2 = 19.92), higher level of TyG-WC (χ 2 = 6.60), and higher zMS (χ 2 = 7.59) were correlated with high CVD. Many metabolic indices have shown a connection with T2DM combined with CVD, and there was a dose-response relationship between HRB co-occurrence and clustering of HRBs and zMS; there was a dose-response relationship between multifactorial intervention and CVH. In the mediation moderation analysis, there was an association between HRB, gender, TyG, TyG-BMI, and CVD. From an intervention management perspective, exercise and no diet intervention were more significant with CVD; moreover, there was an association between intervention management, gender, zMS, TyG-WC, TyG-BMI, TG/HDL, and CVD. Finally, there was an association between sex, CVH, and CVD. Sensitivity analysis demonstrated that our results were robust. CVD is one of the common complications in patients with type 2 diabetes, and its long-term outcome will have more or less impact on patients. Our findings suggest the potential benefits of scaling up multifactorial and multifaceted interventions to prevent CVD in patients with T2DM.

Investigation of heat and mass transfer of flow structures generated by a pulsed surface arc discharge actuator in quiescent air

Pulsed Surface Arc Discharge (PSAD) actuators can improve the aerodynamic performance of aircraft due to their fast response speed and wide frequency band. Understanding the flow structure induced by arc discharge and its transfer process is the key to the sensible use of plasma excitation for flow control. This paper has investigated the dynamic heat and mass transfer process of charged particle clusters generated by arc discharge theoretically and experimentally. The results show that the clusters are composed of charged particles, and the thermal effect is the macroscopic manifestation of the thermal motion of charged particles. The heat and mass transfer processes of charged particle clusters can be expressed as a function of temperature. During heat and mass transfer, the transfer mode of the plasma cluster composed of charged particles will change. The plasma cluster will change from forced convection in the initial stage to natural convection in the final stage, and the Richardson number is different in different stages. The heat released by the gas discharge and the heat released by the plasma mass transfer will form accumulated heat in the space and change the temperature difference, thereby affecting the process of heat and mass transfer. This paper has constructed a model describing pulsed plasma clusters' dynamic heat and mass transfer. Furthermore, the dynamic mode decomposition results of the theoretical model function show that plasma clusters mainly conduct the mass transfer through low-frequency and heat transfer through high-frequency modes.

Pyrolysis of Schiff‐Base Manganese Clusters: Effect of Ligand Modulation on the Performance of Supercapacitor Electrodes

AbstractLigand modulation on metal organic clusters endow them with different physical and chemical properties, while how ligand modulation further affects the electrochemical behavior of pyrolytic derivatives is still unclear. Herein, we constructed two trinuclear manganese clusters 1‐Mn3 [Mn3L12(Cl)2] [L1=N1,N3‐bis(3‐methoxysalicylidene) diethylenetriamine] and 2‐Mn3 [Mn3L22(C7H4O2)2] [L2=N1,N3‐bis(3‐salicylidene) diethylenetriamine] based on nitrogen‐rich Schiff‐base pentadentate ligands. The introduction of TG‐MS (thermogravimetry associated with mass spectroscopy) explores the difference and universality of the pyrolysis mechanism of two trinuclear manganese clusters, and divides the pyrolysis process into three Areas (Area I/II/III) according to temperature. Combined with other characterization techniques, the materials in these three areas were analyzed to explain the effect of ligand modification on the electrochemical properties of cluster pyrolysis derivatives. It is found that the Area III derivatives have the best capacitance performance, when the current density is 1 A g−1, the specific capacitance of 1‐900 is 1717 F g−1, and 2‐900 is 350 F g−1. By comparison of the phase evolution process and electrochemical performance of the two manganese clusters, it is proposed that the crumbling of the molecular structure and stacking mode of trinuclear manganese clusters during pyrolysis will affect the capacitive properties of the derivatives. This work provides a guidance for the differences of the properties of pyrolytic derivatives under ligand modulation.

Graph Ranked Clustering Based Biomedical Text Summarization Using Top k Similarity

Text Summarization models facilitate biomedical clinicians and researchers in acquiring informative data from enormous domain-specific literature within less time and effort. Evaluating and selecting the most informative sentences from biomedical articles is always challenging. This study aims to develop a dual-mode biomedical text summarization model to achieve enhanced coverage and information. The research also includes checking the fitment of appropriate graph ranking techniques for improved performance of the summarization model. The input biomedical text is mapped as a graph where meaningful sentences are evaluated as the central node and the critical associations between them. The proposed framework utilizes the top k similarity technique in a combination of UMLS and a sampled probability-based clustering method which aids in unearthing relevant meanings of the biomedical domain-specific word vectors and finding the best possible associations between crucial sentences. The quality of the framework is assessed via different parameters like information retention, coverage, readability, cohesion, and ROUGE scores in clustering and non-clustering modes. The significant benefits of the suggested technique are capturing crucial biomedical information with increased coverage and reasonable memory consumption. The configurable settings of combined parameters reduce execution time, enhance memory utilization, and extract relevant information outperforming other biomedical baseline models. An improvement of 17% is achieved when the proposed model is checked against similar biomedical text summarizers.

Competitive coordination and Lewis-base interactions of amines in supertetrahedral cluster-based materials by a controllable naked T3-InS precursor method: from isolated clusters with various substituted ligands, chains to 3-D open frameworks

The regulation of amines can convert ligand-free T3-InS clusters into a variety of products. These results indicate that the coordination ability N atoms of amines has an important influence on the formation and assembly mode of clusters.

Analysis of spatial-temporal distribution characteristics and natural infection status of SFTS cases in Hefei from 2015 to 2021.

To analyze the prevalence and spatial-temporal characteristics of severe fever with thrombocytopenia syndrome (SFTS), clustering mode of transmission, and the serological dynamic detection results in multiple areas in Hefei from 2015 to 2021, and to provide the basis for SFTS prevention and control. Case data were obtained from the Chinese Disease Control and Prevention Information System. Information on the clustering outbreak was obtained from the outbreak investigation and disposal report. Population latent infection rate information was obtained from field sampling in multiple-incidence counties in 2016 and 2021 by multi-stage random sampling. Epi data3.2 and SPSS 16.0 softwares were used to perform a statistical analysis of the data on SFTS cases, and QGIS 3.26 software was used to draw the incidence map with township (street) as unit. The an average annual reported incidence rate of SFTS in Hefei from 2015 to 2021 was 0.65/100,000, and the case fatality rate was 9.73%. The overall prevalence of SFTS epidemics in Hefei City showed a fluctuating upward trend from 2015 to 2021 (χ2trends = 103.353, P < 0.001). Chaohu City, Feixi County, Feidong County and Lujiang County ranked the top 4 in the city in terms of average annual incidence rate. The number of epidemic-involved towns (streets) kept increasing ((χ2trend = 47.640, P = 0.000)). Co-exposure to ticks accounted for the majority of clustered outbreaks and also human-to-human outbreaks. Population-based latent infection rate surveys were conducted in four SFTS multi-incidence counties, with 385 people surveyed in 2016 and 403 people surveyed in 2021, increasing the population-based latent infection rate from 6.75% to 10.91%, just as the incidence rate increased. The incidence rate of SFTS in Hefei is obviously regional, with an expanding trend in the extent of the epidemic involved. Co-exposure to ticks accounted for the majority of clustered outbreaks and the latent infection rate cannot be ignored.

Investigation of Energy Efficient Clustering Algorithms in WSNs: A Review

In recent years, Wireless Sensor Networks (WSNs) are attracting more attention in many fields as they are extensively used in a wide range of applications, such as environment monitoring, the Internet of Things, industrial operation control, electric distribution, and the oil industry. One of the major concerns in these networks is the limited energy sources. Clustering and routing algorithms represent one of the critical issues that directly contribute to power consumption in WSNs. Therefore, optimization techniques and routing protocols for such networks have to be studied and developed. This paper focuses on the most recent studies and algorithms that handle energy-efficiency clustering and routing in WSNs. In addition, the prime issues in these networks are discussed and summarized using comparison tables, including the main features, limitations, and the kind of simulation toolbox. Energy efficiency is compared between some techniques and showed that according to clustering mode “Distributed” and CH distribution “Uniform”, HEED and EECS are best, while in the non-uniform clustering, both DDAR and THC are efficient. According to clustering mode “Centralized” and CH distribution “Uniform”, the LEACH-C protocol is more effective.

Viscoelastic behavior and fragility of Se-deficient chalcogenide liquids in As-P-Se system

The viscoelastic behavior of supercooled Se-deficient liquids in the series As x Se 100-x (40 ≤ x ≤ 60) and P x As 4–x Se 3 (0 ≤ x ≤ 2.8) are studied using parallel plate rheometry. The compositional variations in the viscosity and fragility of these liquids are shown to be consistent with the corresponding structural evolution. While the shear relaxation of As x Se 100-x liquids with 40 ≤ x ≤ 50 is associated with the dynamics of As Se bond scission/renewal, the As-rich liquids with x ≥ 55 are found to display an additional low-frequency process, which is related to a cooperative interconversion between molecular and network structural moieties. A similar behavior is also exhibited by the As-rich liquids in the P x As 4–x Se 3 series. In contrast, the P-rich liquids characterized by high molecule content display a power-law relaxation behavior resulting from a rather broad distribution of relaxation timescales associated with various dynamical modes of single molecules and molecular clusters.

Power Generation Scheduling for a Hydro-Wind-Solar Hybrid System: A Systematic Survey and Prospect

In the past two decades, clean energy such as hydro, wind, and solar power has achieved significant development under the “green recovery” global goal, and it may become the key method for countries to realize a low-carbon energy system. Here, the development of renewable energy power generation, the typical hydro-wind-photovoltaic complementary practical project, is summarized, and some key problems in complementary systems such as the description and prediction of the power generation law in large-scale stations, risk management, and coordinated operation are analyzed. In terms of these problems, this paper systematically summarizes the research methods and characteristics of a hydro-wind-solar hybrid system and expounds upon the technical realization process from the prediction and description of wind and solar power station cluster output, the risks brought about by large-scale renewable energy grid-connected operation, and the long-term and short-term coordination modeling and resolution thoughts on the hydro-wind-solar hybrid system in cluster mode. Finally, based on the aforementioned analysis, the existing research gaps are discussed from the standpoints of generation forecast, risk management, and cluster scheduling, and the future work outlook is presented accordingly. A hybrid system that combines hydro, wind, and solar energy is emerging as a way to make up for each other’s shortcomings and will be a fruitful area of study in the future.

Temperature-sensitive contacts in disordered loops tune enzyme I activity

Homologous enzymes with identical folds often exhibit different thermal and kinetic behaviors. Understanding how an enzyme sequence encodes catalytic activity at functionally optimal temperatures is a fundamental problem in biophysics. Recently it was shown that the residues that tune catalytic activities of thermophilic/mesophilic variants of the C-terminal domain of bacterial enzyme I (EIC) are largely localized within disordered loops, offering a model system with which to investigate this phenomenon. In this work, we use molecular dynamics simulations and mutagenesis experiments to reveal a mechanism of sequence-dependent activity tuning of EIC homologs. We find that a network of contacts in the catalytic loops is particularly sensitive to changes in temperature, with some contacts exhibiting distinct linear or nonlinear temperature-dependent trends. Moreover, these trends define structurally clustered dynamical modes and can distinguish regions that tend toward order or disorder at higher temperatures. Assaying several thermophilic EIC mutants, we show that complementary mesophilic mutations to the most temperature-sensitive positions exhibit the most enhanced activity, while mutations to relatively temperature insensitive positions exhibit the least enhanced activities. These results provide a mechanistic explanation of sequence-dependent temperature tuning and offer a computational method for rational enzyme modification.

Outdoor ventilation evaluation and optimization based on spatial morphology analysis in Macau

Owing to Macau's high urban development intensity, outdoor ventilation is important to enhance human comfort. In this study, four morphological indices as frontal area index (FAI), site coverage (SC), building height (BH) and floor area ratio (FAR) were mapped and analyzed by establishing a refined three-dimensional urban digital model. Then indicator analysis, numerical simulation and LST retrieval were comprehensively used to assess the present outdoor ventilation conditions of Macau. The results showed that Macau's overall spatial morphology was not conducive to ventilation. In hot season, the cool sea breeze was obstructed by high-rise buildings in coastal area of the northern peninsula and difficult to infiltrate into the inner city. In cold season, the high pedestrian level wind speed of urban blocks in coastal areas of southern island was not good for wind protection. In Macau's northern peninsula, three potential wind corridors that connecting several existing open spaces are suggested. In southern island, a clustered urban development mode is proposed to create a wind corridor network. In addition, the existing heat islands in the windward side of wind corridors can be reduced by optimizing land surface. For pedestrian-level ventilation, the wind speed of traditional neighborhoods can be enhanced by reducing site coverage and introducing high-rise buildings during urban renewal. Wind protection methods should be considered in existing coastal urban areas, and low-rise high-density development mode is recommended for coastal new town planning in southern island. This research presents an opportunity to assist urban planners and researchers in developing a comprehensive understanding of Macau's ventilation condition, and provides theoretical support for planning practices for Macau and cities with comparable conditions.

Role of wettability contrast on nanoscale condensation over hybrid wetting surface with gradient and patterned wetting configuration at various philic-phobic content

This study aims to explore the effect of the relative philic-phobic strength on nanoscale condensation over hybrid wetting surfaces at various philic-phobic contents through molecular dynamics simulation. The molecular system under consideration essentially consists of argon atoms (liquid and vapor) bound by two platinum substrates. Following equilibration of the simulated system at 90 K, the temperature of the lower substrate is raised to induce evaporation of the adjacent liquid argon, which eventually condenses on the upper wall, maintained at equilibration temperature. Two different hybrid wetting configurations of the upper wall have been considered, namely: functional gradient wetting (FGW) and (b) patterned wetting. The relative strength as well as the content of philic-phobic segments for both hybrid wetting configurations have been altered to explore key metrics of nanoscale condensation process such as onset of nucleation cluster, coalescence and subsequent condensate growth mode, transient as well as time averaged condensation rate and heat transfer at the condensing wall. Results obtained in the present study indicate that combining strong hydrophilic segments with weak hydrophobic segments improves the performance of a hybrid wetting surface. Nonetheless, the difference between gradient wetting and patterned wetting distribution has been found to be small for higher philic content of the condensing wall. Also findings of the present atomistic study have been found consistent with classical theories in context to heterogeneous condensate nucleation, coalescence and subsequent growth.