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We report on a method of measuring the stiffness in photophoretic force tweezers in air by using an experimental configuration with two counter-propagating hollow beams. By setting the optical traps of both beams in the same focal plane of the camera, we are able to record the flight procedure of a trapped particle into the other trap after the initial trapping beam is switched off. Then, the stiffness of optical trap can be obtained by fitting the relationship of particle position vs time during the flight procedure. It is found that the measurement is tolerant to the distance between the traps and laser power variation. In addition, the measured stiffness is demonstrated applicable in determining the size of aerosol particles. The reliable method provided in this work is not only useful in studying the physical behavior of signal particle under atmosphere condition but also meaningful in the applications of aerosol studies, such as in situ aerosol characterization and the local surrounding environment sensing. [ABSTRACT FROM AUTHOR]

As China transitions into a deeply aging society, the elderly population's growth has driven a rapid increase in elderly care institutions and facilities during the "13th Five-Year Plan" period, rising by over 235% compared to the "12th Five-Year Plan". The ongoing normalization of COVID-19 prevention measures has underscored the urgent need to improve natural ventilation in elderly care residential facilities. This study conducted empirical surveys to assess the current state of natural ventilation in typical elderly care facilities and analyzed the architectural elements influencing it. By examining the needs and preferences of the elderly for natural ventilation, two basic living space layout types were identified through typological analysis. Suitable CFD simulation software was then employed to model key elements, and effective methods to enhance ventilation were summarized. This study found that modifying the floor plan to reduce the depth of south-facing rooms to 8.4 m, relocating external openings to the center of the rooms, adjusting the ratio of ventilation openings to room area to greater than 1/12, and adding 0.5 m high windows facing internal traffic roads can significantly improve indoor ventilation while maintaining privacy. Furthermore, placing the main activity and resting areas of the elderly in well-ventilated zones with minimal drafts can enhance both comfort and ventilation effectiveness. The research provides a scientific basis and methodological guidance for the construction and renovation of elderly care residential facilities. [ABSTRACT FROM AUTHOR]

With the development of urban population aging in China, enhancing the quality of community living environments for the elderly has become crucial. Traditional residential planning focused on functionality, neglecting the elderly's active participation and mutual aid needs. This paper proposes the development of urban community environments promoting "living mutual aid" to improve elderly life quality and practice active aging. Using qualitative and quantitative methods, the study identifies key components of mutual aid, explores the relationship between mutual aid behaviors and spatial composition, and outlines strategies for designing community environments that support mutual aid. Based on "active aging" theory, the study qualitatively summarizes the concept of mutual aid among the elderly through literature and policy analysis. Surveys, interviews, and observations in Xi'an's typical communities were conducted, with results analyzed using factor and frequency analysis. The study categorizes mutual aid activities and behavior characteristics, and explores the relationship between behavior and spatial needs using environmental behavior theory. It identifies mutual aid space units and suggests types, paths, strategies, and methods for integrating these units into community environments. The findings provide scientific guidance for urban community planning and valuable references for creating elderly-friendly urban habitats. [ABSTRACT FROM AUTHOR]

Breast cancer is the most prevalent cancerous tumor in women, characterized by different subtypes and varying responses to treatment. The continued evolution of breast cancer diagnosis and management has resulted in a transition from a one‐size‐fits‐all approach to a new era of personalized treatment plans. Therefore, it is essential to accurately identify the biological characteristics of breast tissue in order to minimize unnecessary biopsies of benign lesions and improve the overall clinical process, leading to reduced expenses and complications associated with invasive biopsy procedures. Challenges for future research include finding ways to predict the response of breast cancer patients to adjuvant systemic treatment. Dual‐energy CT (DECT) is a new imaging technology integrating functional imaging and molecular imaging. Over the past decade, DECT has gained relevancy, especially in oncological radiology. This article proposed a literature review of the application and research status of DECT in breast cancer treatment strategy determination and prognosis prediction. [ABSTRACT FROM AUTHOR]

The supercritical CO2 Brayton cycle integrated with a solar power tower system has the advantages of high efficiency, compact cycle structure, strong scalability, and great power generation potential, which can positively deal with the energy crisis and global warming. The selection and optimization of design points are very important for actual operating situations. In this paper, the thermodynamic and economic models of the 10 MWe supercritical CO2 Brayton cycle for application in solar power tower system are established. Multi-objective optimizations of the simple recuperative cycle, reheating cycle, and recompression cycle at different compressor inlet temperature are completed. The thermal efficiency and the levelized energy cost are selected as the fitness functions. The ranges of the optimal compressor inlet pressure and reheating pressure on the Pareto frontier are analyzed. Finally, multiobjective optimizations and analysis of the supercritical CO2 Brayton cycle at different ambient temperature are carried out. This paper investigates the influence of the compressor inlet temperature and ambient temperature on the thermal efficiency and economic performance of the supercritical CO2 Brayton cycle.

In order to understand the data of crack of wall in houses as much as possible and ensure the safety of life and property of residents, a kind of crack detection system of wall in houses based on SCM was designed to detect the crack of wall in houses. In the system, the main work includes the design for data acquisition module of crack in the wall and data receiving and processing control module. For detailed, the work can be divided into selection of sensor detecting cracks, hardware design and software design of the system. The hardware design consists of the design of data acquisition module and data receiving and processing control module, and the software design consists of the design of data acquisition program and data receiving and processing control program and so on. Finally, the hardware and software of system designed were debugged and it proved that the desired effect was achieved for the design in practice.

AI is becoming increasingly important in promoting the energy revolution of carbon‐neutral to achieve sustainable development. Induced by the large implementation of renewable energy, the more complexities and uncertainties in the future carbon‐neutral energy systems make their designs hard accessible to the conventional methods, so machine learning (ML) especially the neural network becomes under focus. Here, we design a deep learning architecture based on convolutional neural networks (DL‐CNN) known for its powerful predicting ability, and first utilize it in a case study of performance prediction of supercritical CO2 Brayton cycle. The design paradigm of DL‐CNN architecture for performance prediction of power cycle is proposed. We also summarize the commonly used fully connected neural network (FC‐NN) in related studies of power cycle design. Through systematically comparing the prediction performance of DL‐CNN and FC‐NN, their respective advantages and application scenarios in energy system design are discussed. In addition, a multiobjective design approach based on DL‐CNN combined with random search is proposed and proved to be feasible by comparing with genetic algorithm. The results show that our proposed DL‐CNN model is much more competitive than FC‐NN model when the training data is sufficient and the prediction condition is complex, in which the prediction accuracy can achieve 99.6%. In the future, our deep learning model may help solve the complex design problems of hybrid carbon‐neutral energy systems. [ABSTRACT FROM AUTHOR]

Supercritical CO2 Brayton cycle has high efficiency, compactness, and excellent power generation potential. In the design of the cycle, some parameters, such as recuperator pinch point temperature difference (ΔTrec,pp), turbine inlet temperature (Ttur,in), and maximum cycle pressure (pmax), are often preset without optimization. Furthermore, different preferences on efficiency and cost tradeoff can significantly affect the optimal design of the cycle, and the influence of different parameters on the design condition and the optimum cycle configuration becomes unclear as the preference changes. In this study, different preferences on efficiency and cost tradeoff are considered, and the effects of cycle configuration and optimization parameter addition on the tradeoff are investigated. In addition, four configurations under different preferences on tradeoff are recommended. Results show that the design condition parameters ΔTrec,pp decrease and Ttur,in and pmax increase as the preference of thermal efficiency (Wth) increases. Different optimized parameters affect the results of the design point and cycle performance. In addition, the simple recuperative cycle and reheating cycle are recommended when low cycle initial cost dominates (Wth<0.598), and the recompression cycle and intercooling cycle are recommended when high cycle thermal efficiency dominates (Wth>0.701). The decision maker can select appropriate configuration according to specific preferences. [ABSTRACT FROM AUTHOR]