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Dynamic traction load classification and cluster analysis play an important guiding role in high-speed rail load forecasting. This study classifies numerous measured traction load data after analyzing the dynamic characteristics of the load during typical operation to predict the dynamic load of high-speed rail traction substations accurately. The K-means clustering method is affected by the location of the initial clustering center, which is prone to cause the problem of inaccurate clustering results. The study proposes a sine cosine-K-means (SCA-K) hybrid algorithm for dynamic traction load classification. The sine cosine algorithm (SCA) can dynamically search for the optimal global solution by simulating the outward fluctuation of the sine and cosine functions interactively. The SCA is adopted to optimize the initial classification status. The K-means algorithm is simple in structure, clear in meaning and fast in computation. A combination of the above two algorithms is applied to perform dynamic traction load classification. The case study is to classify the dynamic traction load of a traction substation and compare the classification effect with the other four algorithms. The simulation results show the silhouette coefficient, cluster center, running time, and other results of the SCA-K and the other four algorithms. The proposed SCA-K has a 1.24% higher silhouette coefficient than the best of other compared methods. Compared with the other four algorithms, SCA-K has a superior clustering effect and operational stability and can improve the classification accuracy of traction load. [ABSTRACT FROM AUTHOR]

A fractional-order proportional-integral-derivative (FO-PID) with two more fractional-order operations can achieve higher control performance than a proportional-integral-derivative (PID). Besides, an active disturbance rejection controller (ADRC) and a fractional-order active disturbance rejection controller (FO-ADRC) with more input information can obtain higher control performance than a PID, an FO-PID. To obtain higher control performance with more information and more fractional-order operations, this paper proposes a high-dimensional multiple fractional-order controller (HDMFOC). The HDMFOC cascades multiple high-dimensional controllers with fractional-order for a controller. The numerical simulations of an automatic generation control (AGC) system and an automatic voltage regulation (AVR) system compare the proposed approach with four other algorithms, i.e., the PID, FO-PID, ADRC, and FO-ADRC. Then, the HDMFOC achieves the highest control performances for AGC and AVR of power systems through multiple dimensional information and multiple fractional-order operations. [ABSTRACT FROM AUTHOR]

With the requirements of an increasingly complex power grid environment and rapidly increasing wind power grid-connected capacity, high rate utilization of wind power can reduce greenhouse gas emissions and alleviate dependence on fossil fuels. Conventional controllers could not achieve accurate control action for doubly-fed wind power systems with high-order, multivariable, strong-coupled, nonlinear characteristics. This paper proposes high-dimensional multiple fractional-order controllers (HDMFOCs) to track the maximum power point of doubly-fed induction generators (DFIGs). The HDMFOC introduces the fractional-order, which extends the integer-order domain to the fractional-order domain, expands the dynamic regulation range, introduces multi-level information, and adds proper adjustable parameters, enhancing robustness and anti-jamming performance of the controller. Case study results show that the HDMFOC has higher control performance than proportional-integral-derivative, fractional-order proportional-integral-derivative, and active disturbance rejection controller. Numerical simulations verify the feasibility and effectiveness of the HDMFOC for DFIG-based wind turbines. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor receptor 1 (TNFR1) is overexpressed in several varieties of carcinoma, including breast cancer. WH701 (Ala-Thr-Ala-Gln-Ser-Ala-Tyr-Gly), which was identified by phage display, can specifically bind to TNFR1. In this study, we labeled WH701 with 18F and investigated its tumor diagnostic value. WH701 was synthesized by standard Fmoc-solid phase synthetic protocols and conjugated by NOTA-NHS. NOTA-WH701 was radiolabeled with 18F using NOTA-AlF chelation reaction. The tumor target properties were evaluated in vitro and in vivo using MCF-7 xenografts and inflammation models. [18F]AlF-NOTA-WH701 was labeled in 25 min with a decay-corrected yield of 38.1 ± 4.8% (n = 5) and a specific activity of 10.4-13.0 GBq/μmol. WH701 had relatively high affinity for MCF-7 cells in vitro and [18F]AlF-NOTA-WH701 displayed relatively high tumor uptake in vivo. The tumor to muscle ratio was 4.25 ± 0.56 at 30 min post-injection (p.i.); further, there was a significant difference between the tumor/muscle and inflammation/muscle (3.22 ± 0.56) ratio, which could differentiate the tumor and inflammation. The tumor uptake of [18F]AlF-NOTA-WH701 could be inhibited by 71.1% by unlabeled WH701 at 30 min p.i. We have developed a promising PET tracer [18F]AlF-NOTA-WH701 for the noninvasive detection of breast cancer in vivo. [ABSTRACT FROM AUTHOR]

The Bohai Bay Basin (BBB) is the largest Cenozoic rifted basin in eastern China, which exhibited a multi-episodic behavior. A 2D multi-episodic finite extension model is employed to estimate the stretching factor and strain rate for each rift episode along six seismic profiles. The modeling is based on a reconstruction of pre-rift crustal and lithospheric thicknesses, and is calibrated with the present-day heat flow and Moho depth. The pre-rift thicknesses of the crust and lithosphere are determined to be 34-39 and 80-105 km. The stretching factors range from 1.28 to 1.97, with a peak in the middle-to-late Eocene during which the average strain rate reached 1.1 × 10 s. Our analyses show that the centers of stretching migrated generally from south to north and from west to east during the Cenozoic. The results also indicate an inverse relationship between variations of the average strain rate and the relative motion rate between Pacific plate and Eurasian plate. Combining the results of the previous studies with ours, we infer that the changing subduction rate of the Pacific plate accompanied by episodic eastward retreat of the subduction zone plays important roles in the episodic extension of the BBB and eastward migration of the centers of stretching. [ABSTRACT FROM AUTHOR]

Following the Lushan M7.0 earthquake on 20 April 2013, a topic of much concern is whether events of M7 or greater could occur again on the southern segment of the Longmenshan fault zone. In providing evidence to answer this question, this work analyzes the tectonic relationship between the Lushan event and the 2008 Wenchuan earthquake and the rupture history of the southern segment of the Longmenshan fault zone, through field investigations of active tectonics and paleoearthquake research, and our preliminary conclusions are as follows. The activity of the southern segment of the Longmenshan fault zone is much different to that of its central section, and the late Quaternary activity has propagated forward to the basin in the east. The seismogenic structure of the 2008 Wenchuan earthquake is the central-fore-range fault system, whereas that of the 2013 Lushan event is attributed to the fore-range-range-front fault system, rather than the central fault. The southern segment of the Longmenshan fault zone becomes wider towards the south with an increasing number of secondary faults, of which the individual faults exhibit much weaker surface activity. Therefore, this section is not as capable of generating a major earthquake as is the central segment. It is most likely that the 2013 earthquake fills the seismic gap around Lushan on the southern segment of the Longmenshan fault zone. [ABSTRACT FROM AUTHOR]

Trenching is a primary technique on paleoseismology to reveal evidence of surface deformation produced by large earthquakes. A good trenching site requires completeness of geologic recording on paleoseismic events and corresponding reliable dating from radiocarbon samples. Based on three-dimension trenching, we show a structure of a small triangular pull-apart basin at the Daqingliangzi section on the Zemuhe fault, then explore interrelation between paleoseismic surface rupturing and evolution of the pull-apart basin, and give a corresponding identification model. Sedimentary boundary of the pull-apart basin is tightly bounded by two branch faults, which produced multiple paleoseismic events with deformation of some large fissures in sequence. Strata are thinner at north of the pull-apart basin, however thicker at south. These above characteristics show that evolution of the pull-apart basin is a continuous sedimentation process accompanying extensional deformation produced by multiple paleoseismic events. Small pull-apart basins are favorable sites for trenching and paleoseismic study on active strike-slip faults. [ABSTRACT FROM AUTHOR]

As revealed by field investigations, the co-seismic surface rupture zone of the 2010 MS7.1 Yushu earthquake, Qinghai is a characteristic sinistral strike-slip feature consisting of three distinct sinistral primary ruptures, with an overall strike of 310°--320° and a total length of 31 km. In addition, an approximately 2-km-long en-echelon tensile fissure zone was found east of Longbao Town; if this site is taken as the north end of the rupture zone, then the rupture had a total length of ~51 km. The surface rupture zone is composed of a series of fissures arranged in an en-echelon or alternating relationship between compressive bulges and tensile fissures, with a measured maximum horizontal displacement of 1.8 m. The surface rupture zone extends along the mapped Garzê-Yushu Fault, which implicates it as the seismogenic fault for this earthquake. Historically, a few earthquakes with a magnitude of about 7 have occurred along the fault, and additionally traces of paleoearthquakes are evident that characterize the short-period recurrence interval of large earthquakes here. Similar to the seismogenic process of the 2008 Wenchuan earthquake, the Yushu earthquake is also due to the stress accumulation and release on the block boundaries resulting from the eastward expansion of Qinghai-Tibet Plateau. However, in contrast with the Wenchuan earthquake, the Yushu earthquake had a sinistral strike-slip mechanism resulting from the uneven eastward extrusion of the Baryan Har and Sichuan-Yunnan fault blocks. [ABSTRACT FROM AUTHOR]

The Anninghe fault is an important active fault along the eastern boundary of Sichuan-Yunnan active tectonic block, and the study of its surface deformation and rupture behavior during strong earthquake in the late Quaternary is of fundamental importance for understanding the future seismic risk of the fault zone or even the entire western Sichuan region. Using the methods of detailed geomorphic and geological survey, digital image analysis, total station instrument survey, excavation of combined trench and dating, we analyze the geomorphologic sequences of the offset strata at several sites where the late Quaternary deformation remnants are fairly well preserved and obtain some new results as follows: Strong earthquake events with left-lateral displacements of about 3 m occurred at the two sites of Zimakua and Yejitong at 1634–1811, 1030–1050 and 280–550 a BP, respectively, and the recurrence interval is 520–660 a; The youngest event in the area of Dahaizi-Ganhaizi should be the earthquake of 1536, other events are at 1768–1826, 2755–4108 and 4108–6593 a BP, respectively, with a recurrence interval of 1300–1900 a. The strong earthquake activity shows a clustering character. The possibility of occurrence of a strong earthquake exists on the north segment of the Anninghe fault sometime in the future. [ABSTRACT FROM AUTHOR]

Tectonically, the large-scale right-lateral strike-slip movement along the Red River fault zone is characterized at its late phase with the southeastward extension and deformation of the Northwestern Yunnan normal fault depression on its northern segment, and the dextral shear displacement on its central-southern segment. Research of the relations between stratum deformation and fault movement on the typical fault segments, such as Jianchuan, southeast Midu, Yuanjiang River, Yuanyang, etc. since the Miocene Epoch shows that there are two times dextral faulting dominated by normal shearing occurring along the Red River fault zone since the Miocene Epoch. The fission track dating (abbreviated to FT dating, the same below) is conducted on apatite samples collected from the above fault segments and relating to these movements. Based on the measured single grain’s age and the confined track length, we choose the Laslet annealing model to retrieve the thermal history of the samples, and the results show that the fault zone experienced two times obvious shear displacement, one in 5.5 ± 1.5 MaBP and the other in 2.1 ± 0.8 MaBP. The central-southern segment sees two intensive uplifts of mountain mass in the Yuanjiang River-Yuanyang region at 3.6–3.8 MaBP and 1.6–2.3 MaBP, which correspond to the above-mentioned two dextral normal displacement events since the late Miocene Epoch. [ABSTRACT FROM AUTHOR]

The Kalpin nappe structure is a strongest thrust and fold deformation belt in front of the Tianshan Mountains since the Cenozoic time. The tectonic deformation occurred in 5–6 striking Mesozoic-Cenozoic fold zones, and some renascent folds formed on the recent alluvial-proluvial fans in front of the folded mountains. We used the total station to measure gully terraces along the longitudinal topographic profile in the renascent fold zones and collected samples from terrace deposits for age determination. Using the obtained formation time and shortening amount of the deformed terraces, we calculated the shortening rate of 4 renascent folds to be 0.1±0.03 mm/a, 0.12±0.04 mm/a, 0.59±0.18 mm/a, and 0.26±0.08 mm/a, respectively. The formation time of the renascent folds is some later than the major tectonic uplift event of the Qinghai-Tibet Plateau 0.14 Ma ago. It may be the long-distance effect of this tectonic event on the Tianshan piedmont fold belt. [ABSTRACT FROM AUTHOR]

The active North China block consists of three second-order blocks: Ordos, North China Plain, and East Shandong-Huanghai Sea blocks. Two active tectonic zones, the Anyang-Heze-Linyi and Tangshan-Cixian zones, exist in the active North China Plain block and have separated the active block into 3 third-order active blocks, Taihangshan, Hebei-Shandong, and Henan-Huai blocks. The 3 third-order active blocks are characterized by their entire motion and are clearly different in their Cenozoic structures and deep structures. The active boundary tectonic zones between the third-order active blocks are less than those between the first- and second-order active blocks in their movement strength, extent, and seismic activity. The density of M· ·6 earthquakes in the boundary zones between active blocks is higher than that within the blocks by 9–22 times in the North China region, up to one order of magnitude on average. M· · 7 earthquakes occurred basically in the boundary zones between active blocks. The difference is not occasional, but reflects the nature of intraplate movement and the characteristics of strong seismic activity and is the powerful evidence for hypothesis of active blocks. [ABSTRACT FROM AUTHOR]

Through study on trenches, analysis of recurrence characteristics and recurrence interval cluster/gap of strong earthquakes along the major active faults on the northern border of Ordos block, we found 62 paleoearthquakes that occurred in the late Quaternary, including 33 earthquakes occurring in the Holocene. The recurrence characteristics of the paleoearthquakes are different at three levels, segments, faults, and fault zones. The strong seismic sequence on the independent segments is mostly characterized by long- and short-interval recurrences, while that on the faults and in fault zone is characterized clearly by random and cluster recurrences. Results of the moving window test indicate that the probabilities of “temporal cluster or gap”, caused by random coincidence as opposed to intersegment contagion, are 64% and 70% for the Serteng piedmont fault and for the south-border fault of Wula Mountains, respectively, no clear interaction among the segments of each fault; while the probability is 26.8% for the whole fault zone, suggesting a clear interaction among the faults of this fault zone. These recurrence characteristics may imply an effect of the entire block motion on the recurrence of strong earthquakes. Moreover, the elapsed time for the Wujumeng Pass-Dongfeng Village segment of Serteng piedmont fault and the Tuzuo Banner-Wusutu and the Hohhot segments of Daqingshan piedmont fault has exceeded the average recurrence interval, hence these three segments may be the possible places for future strong earthquakes. [ABSTRACT FROM AUTHOR]