Most damaged reinforced concrete (RC) frame structures still can be used after earthquake, it is important to assess the residual performance of damaged structures. However, quantitatively evaluate ...the residual performance of damaged structures still presents difficulties due to the lack of suitable indicators. For studying and estimating the residual bending bearing capacity (RBC) of RC columns under cyclic loading properly, a new method is proposed, which is characterized based on fiber-beam element damage in section. Firstly, two quantitative indexes, fiber damage index (FDI) and section damage index (SDI) based on fiber-beam elements, are suggested. Weak section (the most damaged part on column) of RC column can be determined utilizing the SDI. Moreover, based on comparison between test and calculation, the section damage status of RC column can be described by FDI. And then a procedure for obtaining RBC considering the damage of the RC column is also introduced, and taking a RC column specimen as an example to realize and examine the whole calculation procedure proposed. Furthermore, for determining RBC of testing specimen, a rule for determining the failure point of RC columns under cyclic loading is proposed and verified. By comparing the RBC determined by the experiment and the calculation of 21 RC columns in the Pacific Earthquake Engineering Research Center structural performance database(PEERSPD), our suggested method of computing the RBC is verified too, which proves that new method can quantitatively assess the performance of the members under cyclic loading.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
An increasing body of research has demonstrated that appropriate stimulation of the meridians and acupoints in the human body can play a preventative and therapeutic role in diseases. This study ...combines the use of infrared thermography with intelligent electrophysiological diagnostic system (iEDS) to accurately diagnose and apply transdermal low-frequency electrical stimulation to treat abnormal meridians in patients with erectile dysfunction (ED). The treatment protocol included 6 treatments (each lasting 30 min and performed twice a week). The International Index of Erectile Function-5 (IIEF-5), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Erection Hardness Scale were used to assess treatment results. A total of 62 patients were included in this study, with 31 patients in the treatment group and 31 patients in the sham therapy group. After six treatments, the treatment group improved significantly in IIEF-5 (15.52 ± 2.06 vs. 18.84 ± 2.67, p < 0.001), PHQ-9 (8.32 ± 6.33 vs. 4.87 ± 4.41, p < 0.001), GAD-7 (5.32 ± 5.08 vs. 2.94 ± 3.31, p = 0.003), and EHS (2.48 (2.00, 3.00) vs. 2.90 (2.00, 3.00), p = 0.007). After six sham treatment sessions, no improvements in any of the scores were reported in the sham therapy group. Following that, this group had an additional six treatments of regular therapy, which resulted in statistically significant improvements in IIEF-5 (16.65 ± 1.96 VS. 19.16 ± 2.40, p < 0.001), PHQ-9 (8.81 ± 6.25 VS. 4.97 ± 4.36, p < 0.001), GAD-7 (5.74 ± 5.18 VS. 3.68 ± 3.42, p < 0.001), and EHS (2.61 (2.00, 3.00) VS. 3.03 (2.00, 4.00), p = 0.003). No adverse events were reported regarding penile discomfort, pain, injury, or deformity. CLINICAL TRIALS: The study protocol is registered in the Clinical Trials Registry with the identification number ChiCTR2300070262.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
There is a common way to enhance the collapse safety of residential houses using extra tilted poles supporting poor structures from the outside before and/or after earthquakes in seismic regions, ...especially in rural areas. But, almost all of these supporting measures are still weak and lack of scientific design and evaluation. This study takes a poorly designed two-bay and three-story RC frame building as an object to explore the effect of this kind of support measures on structural seismic resistance by comparing with a standard-designed RC frame structure model as a contrastive case. The results obtained by performance-based methods indicate that extra poles can improve the seismic collapse safety and reduce structural seismic damage of the poorly designed structure (PDS) effectively. The median collapse capacity parameter θ increases from 1.31 g to the range of 1.92∼2.39 g, and SaT1;10% (spectral acceleration at the first-mode period which causes 10% probability of structural collapse) also increases from 0.57 g to the range of 0.75∼1.08 g. Study of dynamic structural damage shows a great damage reduction of PDS under seismic loads, especially SaT1 = 0.2 g. This study proves that this simple measure can improve the seismic resistance of PDS into an acceptable level by taking our suggested practical and efficient supporting schemes.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Emergency remote sensing mapping can provide support for decision making in disaster assessment or disaster relief, and therefore plays an important role in disaster response. Traditional emergency ...remote sensing mapping methods use decryption algorithms based on manual retrieval and image editing tools when processing sensitive targets. Although these traditional methods can achieve target recognition, they are inefficient and cannot meet the high time efficiency requirements of disaster relief. In this paper, we combined an object detection model with a generative adversarial network model to build a two-stage deep learning model for sensitive target detection and hiding in remote sensing images, and we verified the model performance on the aircraft object processing problem in remote sensing mapping. To improve the experimental protocol, we introduced a modification to the reconstruction loss function, candidate frame optimization in the region proposal network, the PointRend algorithm, and a modified attention mechanism based on the characteristics of aircraft objects. Experiments revealed that our method is more efficient than traditional manual processing; the precision is 94.87%, the recall is 84.75% higher than that of the original mask R-CNN model, and the F1-score is 44% higher than that of the original model. In addition, our method can quickly and intelligently detect and hide sensitive targets in remote sensing images, thereby shortening the time needed for emergency mapping.
Grid-connected converter with LCL filter plays an important role in renewable power generation systems. However, existing control techniques face several challenges in practice (e.g., difficulty in ...parameter design, slow dynamic response, and poor robustness under slowly time-varying filter parameter, deadtime of power devices, and external disturbances). To solve these difficulties, a passivity-based fractional-order sliding-mode control (PBC-FOSMC) hybrid controller, which combines the merits of passivity-based control (PBC) and FOSMC, is proposed, where the inputs of the passive controller are the outputs of the FOSMC controller. First, a passive current controller is designed based on the Euler-Lagrange model established by damping injection according to the PBC theory, which can make the system automatically converge to meet the energy dissipation law. Second, an FOSMC controller is designed to further enhance the system robustness to counter disturbances and compensate the reference current accuracy of PBC. The introduced fractional order can successfully suppress the undesired chattering due to the switching behaviors in conventional sliding-mode control. Third, the hybrid PBC-FOSMC controller is derived and system stability is analyzed. Finally, experimental results under 10-kW prototype validate the excellent performance of the proposed method in terms of robustness, dynamic performance, strong perturbation rejection ability, etc., and the desired control targets are achieved.
This paper proposes a discrete-time fuzzy fractional-order sliding-mode control (Fuzzy-FOSMC) dual loop current controller for a three-phase LCL-type grid-connected converter (GCC) with reduced ...order. Conventional sliding-mode control (SMC) has been widely used in GCC due to its robustness to disturbances. However, the chattering in SMC may reduce the tracking performance of the controller, and even lead to system instability. To solve this problem, a Fuzzy-FOSMC controller is proposed in this paper. The introduced fractional-order term can suppress the chattering, and the fractional-order of FOSMC is further adjusted by the fuzzy controller to improve the overall system performance. In addition, the inner loop is implemented by a Fuzzy-FOSMC controller to ensure the tracking of the converter-side current, making the LCL-GCC converter behave like a controllable current source converter with a capacitive-inductive filter, the grid current control problem falls from a third-order to a reduced order system, which solves some difficulties on the design of most controller types. The stability of the two-stage PV system is analyzed. Finally, the effectiveness of the proposed controller is verified by experiments.
•A FOSMC controller is proposed for converter-side current tracking control, which makes the converter to behave like a current source inverter with a CL filter. Compared with existing methods, it exhibits great advantages in current convergence speed, steady-state tracking error, robustness to filter parameter variations and dc-bus voltage changes.•To increase the system robustness, based on the fixed parameters of the FOSMC, a fuzzy controller is designed to adjust the fractional order of FOSMC, which could greatly suppress the chattering in conventional SMC.•By establishing the small signal model of the PV LCL grid connected inverter, the matrix of the overall linear state equation of the PV system including MPPT is obtained, and the stability analysis of the PV system is realized.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Karayaylak Glacier surge initiated from May 2014 and terminated on October 2015.•In the active period, the maximum velocity reached 20.1 m d−1.•The receiving zone experienced an average surface ...elevation gain of 36.8 ± 1.5 m.•Landsat, Gaofen-1 and Ziyuan-3 images were used to monitor glacier surging.•Karayaylak Glacier surge was controlled by hydrology.
Glacier surges in the Pamir have been widely documented, but the surge mechanism remains poorly known. The Karayaylak Glacier is the first reported surging glacier in eastern Pamir but different dates and possible triggers were published. In this research, the Karayaylak Glacier was studied using an extensive Landsat and Ziyuan-3 (ZY-3) satellite image set. The active phase initiated in May to June 2014, and experienced a peak velocity of 20.1 ± 0.7 m d−1 in May 2015, terminating in October 2015. During 2014–2015, the reservoir zone experienced an average surface elevation reduction of 33.1 ± 1.5 m, and the receiving zone experienced an average surface elevation gain of 36.8 ± 1.5 m. The large basal sliding during the active phase (2014–2015) was likely driven by high water pressure at the bed in an inefficient drainage system. A large volume of water released at the end of the active phase indicated the drainage at the glacier base became more efficient. The abrupt peak velocity, the short active phase and the changes in drainage suggest that the Karayaylak Glacier surge was controlled by hydrology. The behaviour of the Karayaylak Glacier was similar to that of the Kyagar Glacier and Shispare Glacier in the Karakoram.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In recent years, the acyl-Coenzyme A thioester hydrolase family (ACOTs) has received wide attention as a key link in lipid metabolism. This family is a class of enzymes that catalyze the hydrolysis ...of fatty acyl-Coenzyme A, disrupting the thioester bond present within acyl-CoA ester molecules to produce free fatty acids (FFA) and the corresponding coenzyme A (CoA). Such enzymes play a very important role in lipid metabolism through maintaining appropriate levels of intracellular FFA and fatty acyl-CoA as well as CoA. It is broadly divided into two distinct subgroups, the type-I α/β-hydrolase fold enzyme superfamily and the type-II 'hot dog' fold superfamily. There are currently four human type-I genes and eight human type-II genes. Although the two subgroups catalyze the same reaction, they are not structurally similar, do not share the same sequence homology, and differ greatly in protein executive functions. This review summarizes the classification of the acyl-CoA thioester hydrolase family, an overview of the structural sequences, and advances in digestive, respiratory, and urinary systemic tumors. In order to explore potential specific drug targets and effective interventions, to provide new strategies for tumor prevention and treatment.
This study focuses on the Yongqiao District in Suzhou City, Anhui Province, China, aiming to analyze the current situation of ground settlement and its influencing factors in the area. The selected ...risk indices include settlement rate, cumulative settlement amount, groundwater level drop funnel, thickness of loose sediment layer, thickness of soft soil layer, and the number of groundwater extraction layers. Additionally, vulnerability indices such as population density, building density, road traffic, and functional zoning are considered. An evaluation index system for assessing land Subsidence risk was established. The risk evaluation of land Subsidence was conducted using the Hierarchical analysis-composite index method and ArcGIS spatial analysis, The evaluation results show that the area of higher risk area is about 2.82 km
, accounting for 0.96% of the total area, mainly distributed in the area of Jiuli village, Sanba Street. The middle risk area is distributed around the higher area, with an area of about 9.18 km
, accounting for 3.13% of the total area. The lower risk areas were distributed in most of the study area, covering an area of 222.24 km
, accounting for 75.82% of the total area. The low risk assessment area is mainly distributed in Bianhe Street and part of Zhuxianzhuang Town, with an area of about 58.88 km
, accounting for 20.09% of the total area. The findings of this study are not only crucial for informing local policies and practices related to land use planning, infrastructure development, and emergency response but also enhance our understanding of the complexities of land Subsidence processes and their interactions with human activities, informing future research and practice in environmental risk assessment and management.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Currently, photovoltaic/electroluminescent (PV/EL) perovskite bifunctional devices (PBDs) exhibit poor performance due to defects and interfacial misalignment of the energy band. Interfacial ...energy‐band engineering between the perovskite and hole‐transport layer (HTL) is introduced to reduce energy loss, through adding corrosion‐free 3,3′‐(2,7‐dibromo‐9H‐fluorene‐9,9‐diyl) bis(n,n‐dimethylpropan‐1‐amine) (FN‐Br) into a HTL free of lithium salt. This strategy can turn the n‐type surface of perovskite into p‐type and thus correct the misalignment to form a well‐defined N–I–P heterojunction. The tailored PBD achieves a high PV efficiency of up to 21.54% (certified 20.24%) and 4.3% EL external quantum efficiency. Free of destructive additives, the unencapsulated devices maintain >92% of their initial PV performance for 500 h at maximum power point under standard air mass 1.5G illumination. This strategy can serve as a general guideline to enhance PV and EL performance of perovskite devices while ensuring excellent stability.
A type of perovskite bifunctional device (PBD) with high photovoltaic (PV) and electroluminescence (EL) performance is developed. Interfacial energy‐band engineering between the perovskite and hole‐transport layer (HTL) is performed to turn the n‐type surface of the perovskite into p‐type and also correct the misalignment to form a well‐defined n–i–p heterojunction.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK