暂无摘要（点击查看原文获取完整内容）
暂无摘要（点击查看原文获取完整内容）
Abstract Digital map processing techniques have enabled new computational methods to extract geographic features from scanned map sources. These are mainly historical maps and are rich in spatiotemporal information which can be derived by descriptive metrics. River channel width is such a typical ecological metric used to calculate properties such as water discharge rates and, generally, often applied in hydrological and ecological monitoring. Measures of river channel width in previous ecological work have successfully measured width based on in situ measurements or remote sensing efforts, but poorly captured the variability in river width due to simplifications of the river network or due to sparse availability of in situ measurements. As river width can greatly vary and change over space and time, capturing its variability with modern geospatial processing techniques is a key interest in interdisciplinary fields studying spatiotemporal changes of riverine properties. This article proposes HydroWidth, a small‐scale approach to measure river width continuously along a channel, capable of capturing the variability in width in simple as well as complex river structures without the use of river masks. The small‐scale approach is compared to two conventional vector‐based discrete river width measurement techniques to test the robustness of the methods in terms of measuring river width and its variability. Furthermore, this article evaluates the adaptability of HydroWidth by performing three experiments measuring river width variability at rivers of different structure, length, and complexity. The methods are applied on rivers of historical map sources, allowing a novel perspective of applying algorithms measuring river width on non‐airborne data sources. Lastly, the computational performance results of the conventional and HydroWidth methods at each experimental site are presented and discussed.
Scientists used some of the most advanced plasma simulations ever created to uncover how the universe builds enormous magnetic fields out of turbulence。 The discovery could reshape our understanding of stars, black holes, neutron star collisions, and dangerous solar eruptions
A decades-old mystery about Saturn has finally been solved thanks to the James Webb Space Telescope。 Scientists discovered that Saturn’s changing “rotation rate” was never caused by the planet speeding up or slowing down, but by powerful winds high in its atmosphere。 Webb’s unprecedented observations revealed that Saturn’s northern lights actively
Scientists at the University of Houston have shattered a long-standing superconductivity record, creating a material that can conduct electricity with zero resistance at the highest temperature ever achieved under normal pressure conditions。 Their breakthrough pushes superconductivity to 151 Kelvin (minus 122°C), beating a record that stood for mor
Scientists have created a tiny chip that can generate, steer, and read light-based information all in one device, marking a major leap toward ultra-fast, energy-efficient computing。 The breakthrough uses atomically thin materials and nanoscale structures to control a unique quantum property of light called the “valley” degree of freedom, allowing i
Scientists at Lawrence Livermore National Laboratory recreated part of the intense chaos inside a nuclear fireball to better understand how radioactive fallout forms。 Their experiments revealed that the way vaporized materials cool can dramatically change the particles that eventually form, especially for volatile elements like cesium
Scientists have uncovered unexpected quantum complexity inside cobalt, a metal long thought to be fully understood。 Advanced measurements revealed a dense network of topological electronic states that remain robust at room temperature。 These states enable extremely fast electron behavior and can be switched or controlled using magnetism
Researchers have developed a compact quantum detector that makes terahertz radiation much easier to detect。 A specially designed metasurface funnels incoming energy into tiny active regions, greatly strengthening the electrical signal produced。 The approach boosted efficiency by roughly 20 times compared to earlier designs and could pave the way fo
Scientists say moons around rogue planets wandering through the galaxy could remain warm enough for life thanks to tidal heating and hydrogen-rich atmospheres。 These dark, starless worlds may have had stable oceans for billions of years — long enough for complex life to potentially emerge
Scientists have successfully tested an AI-designed universal coronavirus vaccine in humans for the first time, finding it to be safe and well tolerated。 The vaccine generated immune responses against multiple coronaviruses, including SARS-CoV-2, SARS, and related bat viruses with pandemic potential。 By targeting features shared across an entire vir
Researchers have finally resolved a key problem in a 100-year-old theory of color, showing that the qualities we perceive in colors are intrinsic to the mathematics of color space itself。 The discovery sharpens our understanding of human vision and could lead to more precise color technologies and visualizations
June's night sky delivers several must-see events, starting with a close encounter between Venus and Jupiter after sunset。 Mercury joins the pair to form a rare three-planet lineup, while the Moon puts on a special show by passing in front of Venus for viewers in parts of the Americas。 The month also marks the start of astronomical summer and the r
NASA’s Fermi telescope has detected what may be the first confirmed gamma-ray signal from a superluminous supernova — one of the most extreme explosions in the universe。 Scientists believe the blast was powered by a rapidly spinning magnetar, an exotic neutron star with unbelievably strong magnetic fields。 The event, called SN 2017egm, erupted 440
A breakthrough hydrogen-production method could make clean fuel far cheaper and easier to generate。 Researchers at the University of Birmingham developed a perovskite-based catalyst that splits water into hydrogen at much lower temperatures than existing technologies, potentially allowing factories, steel plants, cement works, and renewable energy
"We look forward to working with Roscosmos on a collaborative approach to address the leaks