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In this work, we demonstrate the performance of a silicon-compatible high-performance self-powered photodetector.A wide detection range from visible (405 nm) to near-infrared (1550 nm) light was enabled by the vertical p-n heterojunction between the p-type antimony telluride (Sb2Te3) thin film and the n-type silicon (Si) substrates. A Sb2Te3 film with a good crystal quality, low density of extended defects, proper stoichiometry, p-type nature, and excellent uniformity across a 4-inch wafer was achieved by atomic layer deposition at 80 {\deg}C using (Et3Si)2Te and SbCl3 as precursors. The processed photodetectors have a low dark current (~20 pA), a high responsivity of (~4.3 Ampere per Watt at 405 nm and ~150 milli-Ampere per Watt at ~1550 nm), a peak detectivity of ~1.65*10^14 Jones, and a quick rise time of ~98 us under zero bias voltage. Density functional theory calculations reveal a narrow, near-direct, type-II bandgap at the heterointerface that supports a strong built-in electric field leading to efficient separation of the photogenerated carriers. The devices have long-term air stability and efficient switching behavior even at elevated temperatures. These high-performance self-powered p-Sb2Te3/n-Si heterojunction photodetectors have immense potential to become reliable technological building blocks for a plethora of innovative applications in next-generation optoelectronics, silicon-photonics, chip-level sensing, and detection., Comment: 11 pages, 1 Table, 5 Figures, Supporting Information

One of the most common forms of data release by National Statistical Institutes (NSIs) are frequency tables arising from censuses and surveys and these have been the focus of statistical disclosure limitation (SDL) techniques for decades. With the need to modernize dissemination strategies, NSIs are considering web-based flexible table builders where users can generate their own tables of interest without the need for human intervention. This has led to a shift in traditional disclosure risks of concern and a move towards inferential disclosure risk where statistical data can be manipulated and combined with other data sources to reveal sensitive information with a high degree of certainty. To protect against inferential disclosure risk, perturbative methods with more formal privacy guarantees are necessary. We examine three post-tabular confidentiality protection methods of additive random noise that can easily be applied ‘on-the-fly’ in a flexible table builder for generating survey weighted frequency tables: the computer science approach guaranteeing a formal privacy model called differential privacy and two SDL approaches of post-randomization and a new technique called drop/add-up-to-q. We demonstrate and compare their application in a simulation study based on survey weighted counts in tables.

The decrease of runoff in the Luanhe river basin, which caused water crisis in Tianjin for several times, was investigated using discharge data covering the period 1956–2002. The data from the differential integral curves of the annual runoff indicate that the decreasing point began in 1979 in the six sub-basins. The decrease of runoff in the Luanhe river basin resulted from the combination of climate effects and human activities, in which the latter plays an important role. This can be illustrated by noting that after 1979 the runoff generated by similar precipitation decreased under the condition that the total precipitation did not decrease in the entire basin. As a result, the annual runoff of the Luanhe river basin after 1979 decreased by about 6.46 × 108 m3 each year. To analyze the runoff characteristics, it is inadequate to seek the runoff trends only and the identification of cyclical component of the runoff as accurate as possible is necessary. From the natural annual runoff discharge time series, we can see the annual runoff fluctuates around the long-term average. Analyzed by VRL (Variable Record Length) method, the main periods of 3, 5–6, 7, 9, 16–20 and 37–39 years were found. The last decade causing water crisis was the driest period in the history, and this condition will last several years from trend analysis and power spectrum analysis. So finding new water sources is urgent to solve water crisis in Tianjin city, and the South-North Water Transfer is a feasible option.