Non-stationary statistical modeling of extreme wind speed series with exposure correction

Mingfeng Huang,Qiang Li,Haiwei Xu,Wenjuan Lou,Ning Lin 한국풍공학회 2018 Wind and Structures, An International Journal (WAS Vol.26 No.3

Extreme wind speed analysis has been carried out conventionally by assuming the extreme series data is stationary. However, time-varying trends of the extreme wind speed series could be detected at many surface meteorological stations in China. Two main reasons, exposure change and climate change, were provided to explain the temporal trends of daily maximum wind speed and annual maximum wind speed series data, recorded at Hangzhou (China) meteorological station. After making a correction on wind speed series for time varying exposure, it is necessary to perform non-stationary statistical modeling on the corrected extreme wind speed data series in addition to the classical extreme value analysis. The generalized extreme value (GEV) distribution with time-dependent location and scale parameters was selected as a non-stationary model to describe the corrected extreme wind speed series. The obtained non-stationary extreme value models were then used to estimate the non-stationary extreme wind speed quantiles with various mean recurrence intervals (MRIs) considering changing climate, and compared to the corresponding stationary ones with various MRIs for the Hangzhou area in China. The results indicate that the non-stationary property or dependence of extreme wind speed data should be carefully evaluated and reflected in the determination of design wind speeds.

Non-stationary statistical modeling of extreme wind speed series with exposure correction

Huang, Mingfeng,Li, Qiang,Xu, Haiwei,Lou, Wenjuan,Lin, Ning Techno-Press 2018 Wind and Structures, An International Journal (WAS Vol.26 No.3

Extreme wind speed analysis has been carried out conventionally by assuming the extreme series data is stationary. However, time-varying trends of the extreme wind speed series could be detected at many surface meteorological stations in China. Two main reasons, exposure change and climate change, were provided to explain the temporal trends of daily maximum wind speed and annual maximum wind speed series data, recorded at Hangzhou (China) meteorological station. After making a correction on wind speed series for time varying exposure, it is necessary to perform non-stationary statistical modeling on the corrected extreme wind speed data series in addition to the classical extreme value analysis. The generalized extreme value (GEV) distribution with time-dependent location and scale parameters was selected as a non-stationary model to describe the corrected extreme wind speed series. The obtained non-stationary extreme value models were then used to estimate the non-stationary extreme wind speed quantiles with various mean recurrence intervals (MRIs) considering changing climate, and compared to the corresponding stationary ones with various MRIs for the Hangzhou area in China. The results indicate that the non-stationary property or dependence of extreme wind speed data should be carefully evaluated and reflected in the determination of design wind speeds.

MiR-340 regulates the growth and metabolism of renal cell carcinoma cells by targeting frizzled class receptor 3

Mingfeng Xiang,Yanqun Huang,Changjun Dai,Gaode Zou 대한약학회 2021 Archives of Pharmacal Research Vol.44 No.2

MicroRNA(miR)-340 is known as a multifunctionalmiRNA related to various types of cancer while itsrole in renal cell carcinoma (RCC) remains to be furtherinvestigated. In the present study, an apparent increase inmiR-340 expression was observed in both clear cell RCCtissues and RCC cell line 786-O and Caki-1. Functionally,the overexpression of miR-340 promoted cell proliferation,migration, invasion, extracellular alanine (Ala) level, andglycolysis level in 786-O cells. Then, frizzled class receptor3 (FZD3) was determined as the target gene of miR-340 andits expression level was negatively regulated by miR-340. The FZD3 silencing abrogated the inhibitory eff ect of miR-340 knockdown on cell proliferation, migration, invasion,Ala level, and glycolysis level in 786-O cells. In conclusion,miR-340 promotes proliferation, migration, and invasion ofRCC cells via suppressing FZD3 expression, and the promotioneff ect of miR-340 on RCC progression may be due to itsregulatory eff ect on glycolysis and Ala level.

Wind field generation for performance-based structural design of transmission lines in a mountainous area

Wenjuan Lou,Hang Bai,Mingfeng Huang,Zhiyong Duan,Rong Bian 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.31 No.2

The first step of performance-based design for transmission lines is the determination of wind fields as well as wind loads, which are largely depending on local wind climate and the surrounding terrain. Wind fields in a mountainous area are very different with that in a flat terrain. This paper firstly investigated both mean and fluctuating wind characteristics of a typical mountainous wind field by wind tunnel tests and computational fluid dynamics (CFD). The speedup effects of mean wind and specific turbulence properties, i.e., turbulence intensity, power spectral density (PSD) and coherence function, are highlighted. Then a hybrid simulation framework for generating three dimensional (3D) wind velocity field in the mountainous area was proposed by combining the CFD and proper orthogonal decomposition (POD) method given the properties of the target turbulence field. Finally, a practical 220 kV transmission line was employed to demonstrate the effectiveness of the proposed wind field generation framework and its role in the performance-based design. It was found that the terrain-induce turbulence effects dominate the performance-based structural design of transmission lines running through the mountainous area.

Numerical simulation of infill CACB wall cracking subjected to wind loads

Ruige Li,Yu Gao,Hongjian Lin,Mingfeng Huang,Chenghui Wang,Zhongzhi Hu,Lingyi Jin 국제구조공학회 2024 Structural Engineering and Mechanics, An Int'l Jou Vol.89 No.5

The cracking mechanism in ceramsite aerated concrete block (CACB) infill walls were studied in low seismic fortification intensity coastal areas with frequent occurrence of typhoons. The inter-story drifts of an eight-story residential building under wind loads and a seismic fortification intensity of six degrees were analyzed by using the PKPM software. The maximum inter-story drift ratio of the structure in wind load was found to be comparable to that under the seismic fortification intensity of six degrees. However, when accounting for the large gust wind speed of typhoon, the maximum inter-story drift ratio was much larger than that obtained under reference wind load. In addition, the finite element models of RC frames were employed by displacement loading to simulate two scenarios with and without window hole in the CACB infill walls, respectively. The simulation results show no signs of cracking in both the infill walls with window hole and those without window for the inter-story drift caused by seismic loads and the reference wind load. However, both types of infill walls experienced structural creaking when assessing the gust wind pressure recorded from previous typhoon monitoring. It is concluded that an underestimate of wind loads may contribute substantially to the cracking of frame CACB infill walls in low seismic fortification intensity coastal areas. Consequently, it is imperative to adopt wind pressure values derived from gust wind speeds in the design of CACB infill walls within frame structures. Finally, the future research directions of avoiding cracks in CACB filled walls were proposed. They were the material performance improving and building structure optimizing.

Genomic Characteristics and the Potential Clinical Implications in Oligometastatic Non–Small Cell Lung Cancer

Rongxin Liao,Kehong Chen,Jinjin Li,Hengqiu He,Guangming Yi,Mingfeng Huang,Rongrong Chen,Lu Shen,Xiaoyue Zhang,Zaicheng Xu,Zhenzhou Yang,Yuan Peng 대한암학회 2023 Cancer Research and Treatment Vol.55 No.3

Purpose Oligometastatic non–small cell lung cancer (NSCLC) patients have been increasingly regarded as a distinct group that could benefit from local treatment to achieve a better clinical outcome. However, current definitions of oligometastasis are solely numerical, which are imprecise because of ignoring the biological heterogeneity caused by genomic characteristics. Our study aimed to profile the molecular alterations of oligometastatic NSCLC and elucidate its potential difference from polymetastasis. Materials and Methods We performed next-generation sequencing to analyze tumors and paired peripheral blood from 77 oligometastatic and 21 polymetastatic NSCLC patients to reveal their genomic characteristics and assess the genetic heterogeneity. Results We found ERBB2, ALK, MLL4, PIK3CB, and TOP2A were mutated at a significantly lower frequency in oligometastasis compared with polymetastasis. EGFR and KEAP1 alterations were mutually exclusive in oligometastatic group. More importantly, oligometastasis has a unique significant enrichment of apoptosis signaling pathway. In contrast to polymetastasis, a highly enriched COSMIC signature 4 and a special mutational process, COSMIC signature 14, were observed in the oligometastatic cohort. According to OncoKB database, 74.03% of oligometastatic NSCLC patients harbored at least one actionable alteration. The median tumor mutation burden of oligometastasis was 5.00 mutations/Mb, which was significantly associated with smoking, DNA damage repair genes, TP53 mutation, SMARCA4 mutation, LRP1B mutation, ABL1 mutation. Conclusion Our results shall help redefine oligometastasis beyond simple lesion enumeration that will ultimately improve the selection of patients with real oligometastatic state and optimize personalized cancer therapy for oligometastatic NSCLC.