基于ArcGIS Engine的风暴潮淹没适应气候变化策略辅助决策系统开发

本研究构建了基于ArcGIS Engine的风暴潮淹没适应气候变化策略辅助决策系统,将风暴潮淹没适应气候变化策略研究过程流程化和简单化,并提供7个面向用户开放的决策端口,辅助决策者做出科学的风暴潮淹没适应气候变化策略选择。以青岛市风暴潮淹没为例的系统应用,进一步验证了该系统能够切实提高研究过程的分析效率,为中国沿海地区的适应风暴潮灾害提供技术支持。

基于Google earth engine渭-库绿洲果园遥感提取

针对干旱区果园大面积遥感提取困难、识别精度低等问题,本研究基于GEE(Google earth engine)平台,综合应用Sentinel-1/Sentinel-2影像构建特征集。通过对比原始特征组合、Jeffries-Matusita(J-M)距离、属性重要度3种优化方式,结合随机森林(Random forest,RF)分类方法,对比得到最佳优化方式,探索果园最优分类特征集。结果表明:识别效果最好的方案为G17 JM,总体精度为91.25%,kappa系数为0.89,面积精度为82.55%。最优特征集为B8_asm、B8_ent、B8_idm、NDVI re3、B6、B7、a、e、b、EVI、B11、B8A、B8、VV。使用J-M距离进行特征集优化,有效降低数据量、提高计算效率,更有利于精确遥感识别果园种植面积。表明GEE快速、准确获取果园种植面积的可行性,为获取果园动态变化提供强有力的基础。

基于Google Earth Engine的八门湾红树林年际变化监测

该文基于Google Earth Engine(GEE)云平台,选择Landsat系列卫星数据,采用支持向量机(support vector machines,SVM)分类方法对八门湾地区进行地物类型分类,并基于分类结果监测该地区红树林年际变化。结果表明:红树林与陆地树木之间除红外波段外反射光谱曲线极其相似,利用红外波段特征指数并结合地形数据可进行有效区分,分类结果总体精度达到0.91;研究区红树林存在先减少后增加的变化趋势,在2009—2013年减少,2014—2016年基本保持不变,2017—2021年缓慢增加,红树林增加和坑塘减少时期是在“南红北柳”政策颁布之后,说明退塘还林政策成效显著;红树林主要是和坑塘相互变化转移,说明毁林造塘和退塘还林是影响该地区红树林变化的重要因素。红树林年际变化监测结果可以精细化分析红树林演变过程,并能精确量化红树林与其他土地类型的转化过程,从而在经济、政策上分析红树林演变因素,更有效地保护红树林。

基于ArcGIS Engine的乡镇区域洪灾应急路径规划和制图系统设计与实现

近年来,极端天气引起的洪涝灾害频繁发生,给人民生命财产安全造成巨大威胁。乡镇区域由于基础设施不够完善、应急救援信息化建设相对薄弱,是人员、经济损失最为严重的区域。针对上述问题,基于ArcGIS Engine设计并开发了乡镇区域洪灾应急路径规划和制图系统,通过设计灾区信息查询、道路更新、救援路径规划、应急地图制图和灾情统计等功能,优化救援路径规划方案,提高应急地图制图效率,为乡镇区域洪灾应急救援提供支持和服务。

基于ArcGIS Engine的梅岭国家森林公园旅游系统的设计与实现

随着人们生活质量的提升,旅游已经变为日常生活的重要组成部分,生态旅游已经成为新兴热门旅游项目。传统的旅游服务平台存在旅游信息资源零散、平台开发程度和服务质量低下等问题,不能满足公众生态旅游服务的需求。本文利用组件式GIS技术并结合C#编程语言,设计并实现了梅岭国家森林公园旅游系统。该系统面向生态旅游的游客,提供旅游信息查询检索、特色旅游路线展示、旅游路线规划、旅游地图设计和其他旅游辅助等功能,提高公园生态旅游服务水平,增强游客旅行体验。

基于Google Earth Engine的洱海流域建成区范围及生态质量变化分析

以洱海流域为研究区,借助Google Earth Engine云平台,利用Landsat 8 OLI系列影像,合成研究区域的增强的指数型建筑指数(EIBI)并对洱海流域建成区进行提取,再对研究区域遥感生态指数进行合成,通过对建成区范围与流域范围内遥感生态指数进行空间相关分析,从而对2014—2021年洱海流域及其建成区进行生态评估。结果表明,EIBI可有效增强建筑信息,使用EIBI可有效、准确地提取研究区域建成区,经过EIBI提取,洱海流域2014—2021年建成区扩张面积共14.712 km2;2014—2021年洱海流域生态明显改善,遥感生态指数增加0.008,其上升速率为0.001/年,流域内超过65%的区域生态得到改善;洱海流域建成区与生态未得到改善区域大致匹配,建成区经过生态修复后生态质量未见显著提升,且建成区生态质量呈逐年下降趋势,说明建成区对环境改善具有阻力。

基于Unreal Engine的虚拟现实技术在元宇宙图书馆中的应用

以虚拟现实技术作为研究切入点,探索元宇宙图书馆建设的技术实现路径。通过文献调研对比分析现有的虚拟现实技术,寻找一种适合高校图书馆自主研发的技术实现方法,并通过具体案例验证该方法的现实可行性。研究发现基于Unreal Engine的虚拟现实技术具有低成本、低代码量、可扩展等优点,适合经费少、计算机人才短缺的高校图书馆。对高校图书馆推进元宇宙图书馆建设具有一定的参考价值。

Research on the Development of Fibroin and Nano-Fiber from Silk Cocoons for Regenerated Tissue Engineering Applications by Electro-Spinning

In this paper, the main goal is to prepare silk fibroin nano-fiber, which is used for regenerated tissue applications. Silk scaffold nano-fibers made by electro-spinning technology can be used in regenerated tissue applications. The purpose of the research is to prepare a silk-fibroin nano-fiber solution for potential applications in tissue engineering. Using a degumming process, pure silk fibroin protein is extracted from silk cocoons. The protein solution for fibroin is purified, and the protein content is determined. The precise chemical composition, exact temperature, time, voltage, distance, ratio, and humidity all have a huge impact on degumming, solubility, and electro-spinning nano-fibers. The SEM investigates the morphology of silk fibroin nano-fibres at different magnifications. It also reveals the surface condition, fiber orientation, and fiber thickness of the silk fibroin nano-fiber. The results show that regenerated silk fibroin and nano-fiber can be used in silk fibroin scaffolds for various tissue engineering applications.

A brief review on the recent development of phonon engineering and manipulation at nanoscales

Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat fow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting task.This work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices,and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.

Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications

Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.

基于Google Earth Engine遥感大数据云平台的盐城盐沼植被精细分类研究

江苏省自1982年开始引种互花米草以来,滨海盐沼植被景观格局发生了巨大变化,芦苇和互花米草面积不断增长,挤占了碱蓬生态位,破坏了生态系统平衡。滨海盐沼湿地是三大蓝碳生态系统之一,具有高固碳和缓解温室效应的生态功能。利用遥感云平台手段监测滨海盐沼植被时空动态变化规律,可为滨海盐沼湿地生态系统保护以及修复提供科学支撑。本文选取植被类型丰富的江苏沿海地区为研究区,基于Google Earth Engine(GEE)平台,选取2000-2020年的Landsat 5、Landsat 7、Landsat 8以及Sentinel-2影像,提出了一种湿地植被提取方法。首先,构建盐城盐沼湿地地表覆盖分类体系,选取样本点,计算特征指数,进行地物分类;然后,利用时间谐波分析法对盐沼植被归一化植被指数(NDVI)变化特征进行分析,确定三类盐沼植被的物候差异;最后,基于物候特征,利用随机森林(Random Forest,RF)分类法提取盐城滨海湿地盐沼植被地表覆盖信息。结果表明:(1)相较传统监测方法,本文所构建的滨海盐沼植被精细化提取方法能够对滨海盐沼植被进行有效细分和监测;(2)2000-2020年,芦苇和互花米草面积呈扩张趋势,碱蓬面积不断缩减;(3)盐城三种典型盐沼植被NDVI值呈现不同变化特征;(4)降水对盐沼植被生长的影响较为显著,气温对盐沼植被生长的直接影响较小。研究结果可为盐城盐沼湿地自然遗产保护以及湿地生态可持续发展提供科学支撑。

Engineering of ovarian tissue for ovarian dysfunctions:A review

This review explores tissue engineering as a potential solution for reproductive health issues in women caused by genetic or acquired diseases,such as premature ovarian failure or oophorectomy.The loss of ovarian function can lead to infertility,osteoporosis,and cardiovascular disease.Hormone replacement therapy is a common treatment,but it has limitations and risks.The review focuses on two main approaches in tissue engineering:scaffold-based(3D printing,electrospinning,decellularization)and scaffold-free(stem cell transplantation,organoid cultivation).Both approaches show promise in preclinical studies for creating functional ovarian tissue.Challenges include vascularization,innervation,long-term function,and safety.Despite these challenges,tissue engineering offers a potential avenue for restoring fertility and hormone balance in women with ovarian dysfunction.

A Review on Silk Fibroin as a Biomaterial in Tissue Engineering

Regenerative medicine progress is based on the development of cell and tissue bioengineering. One of the aims of tissue engineering is the development of scaffolds, which should substitute the functions of the replaced organ after their implantation into the body. The tissue engineering material must meet a range of requirements, including biocompatibility, mechanical strength, and elasticity. Furthermore, the materials have to be attractive for cell growth: stimulate cell adhesion, migration, proliferation and differentiation. One of the natural biomaterials is silk and its component (silk fibroin). An increasing number of scientists in the world are studying silk and silk fibroin. The purpose of this review article is to provide information about the properties of natural silk (silk fibroin), as well as its manufacture and clinical application of each configuration of silk fibroin in medicine. Materials and research methods. Actual publications of foreign authors on resources PubMed, Medline, E-library have been analyzed. The selection criteria were materials containing information about the structure and components of silk, methods of its production in nature. This article placed strong emphasis on silk fibroin, the ways of artificial modification of it for use in various sphere of medicine.

Phase engineering of Ni-Mn binary layered oxide cathodes for sodiumion batteries

Nickel-manganese binary layered oxides with high working potential and low cost are potential candidates for sodium-ion batteries,but their electrochemical properties are highly related to compositional diversity.Diverse composite materials with various phase structures of P3,P2/P3,P2,P2/O3,and P2/P3/O3 were synthesized by manipulating the sodium content and calcination conditions,leading to the construction of a synthetic phase diagram for Na_(x)Ni_(0.25)Mn_(0.75)O_(2)(0.45≤x≤1.1).Then,we compared the electrochemical characteristics and structural evolution during the desodiation/sodiation process of P2,P2/P3,P2/03,and P2/P3/O3-Na_(x)Ni_(0.25)Mn_(0.75)O_(2).Among them,P2/P3-Na0.75Ni0.25Mn0.75O2exhibits the best rate capability of 90.9 mA h g^(-1)at 5 C,with an initial discharge capacity of 142.62 mA h g^(-1)at 0.1 C and a capacity retention rate of 78.25%after 100 cycles at 1 C in the voltage range of 2-4.3 V.The observed superior sodium storage performance of P2/P3 hybrids compared to other composite phases can be attributed to the enhanced Na^(+)transfer dynamic,reduction of the Jahn-teller effect,and improved reaction reversibility induced by the synergistic effect of P2 and P3 phases.The systematic research and exploration of phases in Na_(x)Ni_(0.25)Mn_(0.75)O_(2)provide new sights into high-performance nickel-manganese binary layered oxide for sodium-ion batteries.

Vulnerability assessment of UAV engine to laser based on improved shotline method

Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a variety of analysis programs for battlefield targets to traditional weapons have been developed,but a comprehensive assessment methodology for targets'vulnerability to laser is still missing.Based on the shotline method,this paper proposes a method that equates laser beam to shotline array,an efficient vulnerability analysis program of target to laser is established by this method,and the program includes the circuit board and the wire into the vulnerability analysis category,which improves the precision of the vulnerability analysis.Taking the UAV engine part as the target of vulnerability analysis,combine with the"life-death unit method"to calculate the laser penetration rate of various materials of the UAV,and the influence of laser weapon system parameters and striking orientation on the killing probability is quantified after introducing the penetration rate into the vulnerability analysis program.The quantitative analysis method proposed in this paper has certain general expansibility,which can provide a fresh idea for the vulnerability analysis of other targets to laser.

Engineering the spectra of photon triplets generated from micro/nanofiber

Quantum light sources are the core resources for photonics-based quantum information processing.We investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversion in micro/nanofiber.The phase mismatching at one-third pump frequency gives rise to non-degenerate photon triplets,the joint spectral intensity of which has an elliptical locus with a fixed eccentricity of√6/3.Therefore,we propose a frequency-division scheme to separate non-degenerate photon triplets into three channels with high heralding efficiency for the first time.Choosing an appropriate pump wavelength can compensate for the fabrication errors of micro/nanofiber and also generate narrowband,non-degenerate photon triplet sources with a high signal-to-noise ratio.Furthermore,the long-period micro/nanofiber grating introduces a new controllable degree of freedom to tailor phase matching,resulting from the periodic oscillation of dispersion.In this scheme,the wavelength of photon triplets can be flexibly tuned using quasi-phase matching.We study the generation of photon triplets from this novel perspective of spectrum engineering,and we believe that this work will accelerate the practical implementation of photon triplets in quantum information processing.

Asbestos Exposure during Gasket Removal from Aircraft Engine

We have previously evaluated asbestos exposure associated with various maintenance procedures on light aircraft. The purpose of this study was to evaluate asbestos exposure during engine maintenance on light aircraft. This test was designed to evaluate the potential for asbestos exposure to mechanics and others who remove asbestos-containing engine gaskets from reciprocating style aircraft engines. Utilized in this test was an air cooled, horizontally opposed, aviation gasoline burning engine, assembled during 1986 and operated intermittently up into 2015, having accumulated 1680 hours run time. Nearly 75% of the asbestos-containing gaskets installed during 1986 were still in place at the time of testing. Chrysotile asbestos contents of such gaskets ranged from 55% to 60% by area, for those of sheet style and 5% by area, for the spiral wound metal/asbestos style. Despite the levels of effort required to effect gasket removals, the professional aircraft mechanic was not exposed to airborne asbestos fibers at the lower limits of sampling and analytical detection achieved;all of which were substantially less than the current Occupational Safety and Health Administration Permissible Exposure Limits for asbestos. The results of this testing indicate an absence of gasket related asbestos exposure risk to mechanics who work with light aircraft engines, including those having asbestos-containing gaskets. These results are consistent with the findings of Mlyarek and Van Orden who studied the asbestos exposure risk occasioned during overhaul of larger radial style reciprocating aircraft engines [1].

Solvation Engineering via Fluorosurfactant Additive Toward Boosted Lithium-Ion Thermoelectrochemical Cells

Lithium-ion thermoelectrochemical cell(LTEC), featuring simultaneous energy conversion and storage, has emerged as promising candidate for low-grade heat harvesting. However, relatively poor thermosensitivity and heat-to-current behavior limit the application of LTECs using LiPF_6 electrolyte. Introducing additives into bulk electrolyte is a reasonable strategy to solve such problem by modifying the solvation structure of electrolyte ions. In this work, we develop a dual-salt electrolyte with fluorosurfactant(FS) additive to achieve high thermopower and durability of LTECs during the conversion of low-grade heat into electricity. The addition of FS induces a unique Li~+ solvation with the aggregated double anions through a crowded electrolyte environment,resulting in an enhanced mobility kinetics of Li~+ as well as boosted thermoelectrochemical performances. By coupling optimized electrolyte with graphite electrode, a high thermopower of 13.8 mV K^(-1) and a normalized output power density of 3.99 mW m^(–2) K^(–2) as well as an outstanding output energy density of 607.96 J m^(-2) can be obtained.These results demonstrate that the optimization of electrolyte by regulating solvation structure will inject new vitality into the construction of thermoelectrochemical devices with attractive properties.

Constructing a biofunctionalized 3D-printed gelatin/sodium alginate/chitosan tri-polymer complex scaffold with improvised biological andmechanical properties for bone-tissue engineering

Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue regeneration.We experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and differentiation.The resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)printing.Morphological studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural stability.The scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue engineering.The tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of gelatin.The enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue regeneration.In vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold surface.In addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its potential for use in bone-tissue engineering.

Ionization Engineering of Hydrogels Enables Highly Efficient Salt‑Impeded Solar Evaporation and Night‑Time Electricity Harvesting

Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar evaporation.However,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread application.Herein,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in brine.The sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar absorbers.The hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported literature.More notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous operation.Meantime,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity.