The morphological evolution of high-rise residential building plan in Shanghai under urban social changes

High-rise residential buildings are not simply objective products of cities, which are influenced by urban social changes and national housing standards. Human-oriented design has been continuously paid attention to in the development of contemporary Chinese urban housing. However, the morphology of high-rise housing in China tends to be in a lack of variety. The paper made a summary of the types of high-rise residential building plan in Shanghai from the 1980s to the present, and explained the process of change from the perspective of urban social changes. The form of high-rise residential plan could be divided into three types: gallery apartment building, tower-type apartment building and combined apartment building under the influence of social economy and housing standard in different periods. From 1980 to 1990, the form of high-rise residential plan was diversified, such as gallery and tower-type apartment building. In 1990s, tower housing became mainstream. In 2000s, the type was dominated by tower-type and combined apartment. Since 2016, China has implemented the two-child policy. To meet the need of various families, the form of residential building plan should be more flexible. The evolution of high-rise residential form can partly reflect the changes of urban society. Research on residential morphology can provide a basis for the sustainable development of high-density cities in China

Novel Mechano-Luminescent Sensors Based on Piezoelectric/Electroluminescent Composites

A high-sensitivity mechano-luminescent sensor was fabricated on the basis of piezoelectric/electroluminescent composites. The working principle of this mechano-luminescent sensor was elucidated by analyzing the relationship between the piezoelectric-induced charges and the electroluminescent effects. When a stress is applied on the piezoelectric layer, electrical charges will be induced at both the top and bottom sides of the piezoelectric layer. The induced electrical charges will lead to a light output from the electroluminescent layer, thus producing a mechano-luminescence effect. By increasing the vibration strength or frequency applied, the mechano-luminescence output can be obviously enhanced. Mechano-luminescence sensors have potential in smart stress-to-light devices, such as foot-stress-distribution-diagnosis systems and dynamic-load-monitors for bridge hanging cables

Application of the improved dynamical–Statistical–Analog ensemble forecast model for landfalling typhoon precipitation in Fujian province

The forecasting performance of the Dynamical–Statistical–Analog Ensemble Forecast (DSAEF) model for Landfalling Typhoon [or tropical cyclone (TC)] Precipitation (DSAEF_LTP), with new values of two parameters (i.e., similarity region and ensemble method) for landfalling TC precipitation over Fujian Province, is tested in four experiments. Forty-two TCs with precipitation over 100 mm in Fujian Province during 2004–2020 are chosen as experimental samples. Thirty of them are training samples and twelve are independent samples. First, simulation experiments for the training samples are used to determine the best scheme of the DSAEF_LTP model. Then, the forecasting performance of this best scheme is evaluated through forecast experiments. In the forecast experiments, the TSsum (the sum of threat scores for predicting TC accumulated rainfall of ≥250 mm and ≥100 mm) of experiments DSAEF_A, B, C, D is 0.0974, 0.2615, 0.2496, and 0.4153, respectively. The results show that the DSAEF_LTP model performs best when both adding new values of the similarity region and ensemble method (DSAEF_D). At the same time, the TSsum of the best performer of numerical weather prediction (NWP) models is only 0.2403. The improved DSAEF_LTP model shows advantages compared to the NWP models. It is an important method to improve the predictability of the DSAEF_LTP model by adopting different schemes in different regions

CRAFTS for Fast Radio Bursts Extending the dispersion-fluence relation with new FRBs detected by FAST

We report three new FRBs discovered by the Five-hundred-meter Aperture Spherical radio Telescope (FAST), namely FRB 181017.J0036+11, FRB 181118 and FRB 181130, through the Commensal Radio Astronomy FAST Survey (CRAFTS). Together with FRB 181123 that was reported earlier, all four FAST-discovered FRBs share the same characteristics of low fluence ($\leq$0.2 Jy ms) and high dispersion measure (DM, $>1000$ \dmu), consistent with the anti-correlation between DM and fluence of the entire FRB population. FRB 181118 and FRB 181130 exhibit band-limited features. FRB 181130 is prominently scattered ($\tau_s\simeq8$ ms) at 1.25 GHz. FRB 181017.J0036+11 has full-bandwidth emission with a fluence of 0.042 Jy ms, which is one of the faintest FRB sources detected so far. CRAFTS starts to built a new sample of FRBs that fills the region for more distant and fainter FRBs in the fluence-$\rm DM_E$ diagram, previously out of reach of other surveys. The implied all sky event rate of FRBs is $1.24^{+1.94}_{-0.90} \times 10^5$ sky$^{-1}$ day$^{-1}$ at the $95\%$ confidence interval above 0.0146 Jy ms. We also demonstrate here that the probability density function of CRAFTS FRB detections is sensitive to the assumed intrinsic FRB luminosity function and cosmological evolution, which may be further constrained with more discoveries.Comment: 9 Pages, 4 Plots and 1 Table. The Astrophysical Journal Letter Accepte

A catastrophe identification method for rainfall time series coupled sequential Mann-Kendall algorithm and Bernaola Galvan algorithm: a case study of the Qinglong River watershed, China

The identification of rainfall catastrophe characteristics is important for rainfall consistency testing in hydrostatistical analysis. In this study, a new classification method (trend, mean and change-rate catastrophe) was proposed and applied to the Qinglong River watershed, Northern China. Two groups of algorithms were compared to obtain the optimal algorithm: the Cumulative-anomaly method and the Sequential Mann-Kendall (SQ-MK) algorithm, the Pettitt algorithm and the Bernaola-Galvan heuristic segmentation (B-G) algorithm. Its parameters were optimized and its robustness was tested. Results revealed that: (1) The SQ-MK algorithm was suitable for trend catastrophe and sensitive to the length of the time series. The most significant point of trend catastrophe in the Qinglong River watershed was in 2012. (2) The sensitivity of parameter P0 (Range value (R) = 4.333) in the B-G algorithm was greater than that of parameter l0 (R = 2.889). (3) The B-G algorithm was suitable for identifying mean catastrophes and insensitive to the length of the time series. In the Qinglong River watershed, mean catastrophe points were identified in 1997, 2002, 2004, 2006, 2009, 2012, and 2018. (4) There was no change-rate catastrophe point in the Qinglong River watershed. Trend catastrophe and mean catastrophe do not necessarily lead to change-rate catastrophe. HIGHLIGHTS The SQ-MK algorithm was suitable for trend catastrophe and sensitive to the length of the time series.; The sensitivity of parameter P0 in the B-G algorithm was greater than that of parameter l0.; The B-G algorithm was suitable for identifying mean catastrophes and insensitive to the length of the time series.; Trend catastrophe and mean catastrophe did not necessarily cause change-rate catastrophe.

A support system for civil aviation navigation equipment security management

Civil aviation navigation equipment system has many weaknesses, which easily causes serious problem to air transportation safety. This paper focuses on a support system for civil aviation navigation equipment security management. Firstly, a sustainability assessment platform was constructed to analysis and find out the weaknesses of equipment network. Next, one network expansion planning platform was built to improve the reliability and business continuity of the whole navigation system. Experiments were carried out based on these two platforms. Also, the equipment network of China's eastern part was expanded based on the business continuity assessment. Results proved that the network business continuity and node efficiencies of new equipment network can satisfy the lowest requirement of economic consumption. Finally, the optimal network expansion planning method has been achieved, proving the effectiveness of the civil aviation navigation equipment security management support system

Reliability Modeling for Humidity Sensors Subject to Multiple Dependent Competing Failure Processes with Self-Recovery

Recent developments in humidity sensors have heightened the need for reliability. Seeing as many products such as humidity sensors experience multiple dependent competing failure processes (MDCFPs) with self-recovery, this paper proposes a new general reliability model. Previous research into MDCFPs has primarily focused on the processes of degradation and random shocks, which are appropriate for most products. However, the existing reliability models for MDCFPs cannot fully characterize the failure processes of products such as humidity sensors with significant self-recovery, leading to an underestimation of reliability. In this paper, the effect of self-recovery on degradation was analyzed using a conditional probability. A reliability model for soft failure with self-recovery was obtained. Then, combined with the model of hard failure due to random shocks, a general reliability model with self-recovery was established. Finally, reliability tests of the humidity sensors were presented to verify the proposed reliability model. Reliability modeling for products subject to MDCFPs with considering self-recovery can provide a better understanding of the mechanism of failure and offer an alternative method to predict the reliability of products