Recent advances in engineering characteristics of near-fault ground motions and seismic effects of building structures

Severe damages of civil infrastructures under near-fault ground motions have impelled the community of earthquake engineering to pay intensive attention and investigation to their engineering characteristics and structural seismic effects. This paper reviews the recent research advances of authors in the engineering characteristics of near-fault ground motions and seismic responses and base-isolated performance analysis of building structures. Firstly, two non-structure-specific intensity measures, such as improved effective peak acceleration and velocity (IEPA, IEPV) were proposed. Two frequency content parameters were also suggested, namely the mean period of Hilbert marginal spectrum Tmh, and coefficient of variance of dominant instantaneous frequency of Hilbert spectrum Hcov which reflects the frequency nonstationary degree of ground motions. Meanwhile, a new stochastic model to synthesize near-fault impulsive ground motions with the feature of the strongest pulse was established. Then, the chaotic and fractal/multifractal characteristics of strong earthquake ground motions were analyzed deeply to explore their complexity from a novel perspective of nonlinear dynamics, and the inherent relation between fractal dimensions and period parameters of near-fault motions was exposed. Moreover, the mechanism of interstory deformation of tall building was illustrated based on engineering properties of pulse-like ground motions and generalized drift spectral analysis. Finally, the influence of ground motion properties on the seismic responses and performance of tall structures and base isolated buildings was revealed

Analysis on the Significance of Effects from Operational Conditions on the Performances of Ultrasonic Atomization Dehumidifier with Liquid Desiccant

AbstractIn this work, simulations were carried out based on a L18×L8 cross-product orthogonal array to investigate the significance of the effects from inlet operational conditions on the performances of the ultrasonic atomization liquid desiccant dehumidification system (UADS), where dehumidification effectiveness was adopted as the performance indicator. Taguchi method was employed to analyze the results. It was found that though all of the inlet operational parameters revealed direct effects on the performances of UADS, the significance of their effects was quite different among which, the desiccant flow rate was the most sensible factor in improving DE while air humidity ratio exhibited the least significance. The results presented in this work may help in achieving the optimal running of the liquid desiccant dehumidification system

Improved Data Transmission Scheme of Network Coding Based on Access Point Optimization in VANET

VANET is a hot spot of intelligent transportation researches. For vehicle users, the file sharing and content distribution through roadside access points (AP) as well as the vehicular ad hoc networks (VANET) have been an important complement to that cellular network. So the AP deployment is one of the key issues to improve the communication performance of VANET. In this paper, an access point optimization method is proposed based on particle swarm optimization algorithm. The transmission performances of the routing protocol with random linear network coding before and after the access point optimization are analyzed. The simulation results show the optimization model greatly affects the VANET transmission performances based on network coding, and it can enhance the delivery rate by 25% and 14% and reduce the average delay of transmission by 38% and 33%

Different yellowing degrees and the industrial utilization of flue-cured tobacco leaves

Yellowing is a key stage in the curing of flue-cured tobacco (Nicotiana tobacum L.) as much of the chemical transformation occurs during this period. This study examined the effect of different yellowing degrees on the value of flue-cured tobacco leaves at the farm level for both processing and manufacturing. The study was conducted in the counties of Chuxiong, Dali, and Yuxi in Yunnan, China over two years. Yellowing treatments have been designed to have either a mild or a regular yellowing degree. Yield, value, appearance, suction property, smoking characteristics, and physical resistance to further processing were investigated to evaluate the effect of degree of yellowing on the industrial utilization of flue-cured tobacco leaves. The regular yellowing degree enhanced yield, value, and appearance compared to the mild yellowing degree, regardless of cultivar or location; however, physical resistance to further processing and the suction property of the mild yellowing degree treatment were better than with the regular yellowing degree regardless of cultivar or location. Furthermore, although the regular yellowing degree recorded higher smoking characteristic scores than the mild yellowing degree immediately after flue-curing, the scores of mild yellowing degree leaves could be further augmented by increasing intensity in the re-drying stage. The smoking characteristic score in the regular yellowing degree can only be increased by low intensity re-drying, and significantly decreased by mild and high intensity re-drying. Therefore, in terms of industrial utilization, mild yellowing is the better choice for flue-curing tobacco. This study also suggested that the current regular yellowing stage in Yunnan should be shortened to meet the demands of the traditional tobacco industry

DreamLLM: Synergistic Multimodal Comprehension and Creation

This paper presents DreamLLM, a learning framework that first achieves versatile Multimodal Large Language Models (MLLMs) empowered with frequently overlooked synergy between multimodal comprehension and creation. DreamLLM operates on two fundamental principles. The first focuses on the generative modeling of both language and image posteriors by direct sampling in the raw multimodal space. This approach circumvents the limitations and information loss inherent to external feature extractors like CLIP, and a more thorough multimodal understanding is obtained. Second, DreamLLM fosters the generation of raw, interleaved documents, modeling both text and image contents, along with unstructured layouts. This allows DreamLLM to learn all conditional, marginal, and joint multimodal distributions effectively. As a result, DreamLLM is the first MLLM capable of generating free-form interleaved content. Comprehensive experiments highlight DreamLLM's superior performance as a zero-shot multimodal generalist, reaping from the enhanced learning synergy.Comment: see project page at https://dreamllm.github.io

Percutaneous transthoracic catheter drainage prior to surgery in treating neonates with congenital macrocystic lung malformation presenting with respiratory distress

BackgoundIt is rarely seen that neonates with congenital macrocystic lung malformation (CMLM) presenting with respiratory distress require emergency intervention. No consensus has been achieved concerning the best policy facing such condition. This study aims to evaluate the efficacy and safety of our strategies in treating neonates with CMLM presenting with respiratory distress.MethodsWe retrospectively reviewed the data of six neonates with CMLM presenting with respiratory distress from April 2020 to October 2022 for whom drainage-prior-to-surgery strategy were adopted and favorable outcomes were obtained. The relevant data was reviewed and analyzed.ResultsAll the patients were prenatally diagnosed with congenital lung malformation and postnatally as congenital macrocystic lung malformation via CT scan. Each neonate accepted percutaneous thoracic catheter drainage prior to surgery. The first and fifth neonates with macrocystic lung mass experienced prompt open lobectomy and delayed thoracoscopic surgery due to failure of air drainage, respectively. The other four patients obtained good drainage of the large air-filled cyst, thus gaining the opportunity for elective thoracoscopic surgery within median 45 days.ConclusionsFor neonates with macrocystic lung malformation presenting with respiratory distress due to mediastinal compression, percutaneous thoracic catheter drainage is worth a shot for elective thoracoscopic surgery due to its feasibility and safety

Highly stable Zn anodes realized by 3D zincophilic and hydrophobic interphase buffer layer

Aqueous zinc-ion batteries (AZIBs) are promising contenders for energy storage systems owing to their low cost and high safety. However, their practical application is hindered by uncontrolled Zn dendrites and other side reactions. Here, the three-dimensional (3D) TiO2/Cu2Se/C heterostructure layer derived from MXene/Cu-MOF is constructed on the Zn anode to control the deposition/dissolution behavior, which has numerous active sites, better electrical conductivity and excellent structural stability. Based on DFT calculation, the built-in electric field (BIEF) formed of TiO2/Cu2Se/C can enhance charge transfer and ionic diffusion to inhibit the dendrites. Furthermore, hydrophobic coating has the ability to impede the corrosion and hydrogen evolution reaction (HER) of zinc anode. Thus, TiO2/Cu2Se/C@Zn enable the stable and reversible Zn plating/stripping process with the outstanding lifetime of 1100 h at 2 mA·cm–2 and even 650 h at 10 mA·cm–2. The batteries constructed with commercial MnO2 cathodes demonstrate the remarkable capacity (248.7 mAh·g−1 at 0.1 A·g−1) and impressive cycle stability (with 71.3% capacity retention after 300 cycles). As well as extending the life of AZIBs, this study is also motivating for other metal anode based secondary batteries

INDOOR AIR QUALITY IN A HAIR SALON

Bachelor'sBACHELOR OF SCIENCE (PROJECT AND FACILITIES MANAGEMENT