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A Content Analysis Study Describing Information Regarding Female Genital Mutilation Present in US Medical Textbooks
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作者 Jennifer Ofoe 《Advances in Sexual Medicine》 2024年第3期31-47,共17页
This study examines the depth of information regarding Female Genital Mutilation (FGM)/Female Cutting (FC) present in US medical textbooks. According to Klein et al. (2018) [1], despite substantial attention regarding... This study examines the depth of information regarding Female Genital Mutilation (FGM)/Female Cutting (FC) present in US medical textbooks. According to Klein et al. (2018) [1], despite substantial attention regarding the effects of FGM, this practice is still ongoing all over the world. Healthcare providers are very important actors who need to understand FGM in order to provide care to girls and women subjected to it, but the small amount of existing work in this area shows a low level of knowledge and training about FGM/FC among U.S. physicians. The Center for Disease Control and Prevention (CDC) first published the estimated number of girls at risk of FGM/FC in the U.S. to be about 168,000 in 1997;that number had increased to 513,000 girls in the US by 2012 (according to Goldberg et al.) In this study, a small sample of medical textbooks were analyzed for the degree to which the textbooks include information regarding FGM/FC. The results of this study show that US medical textbooks do not include information regarding FGM/FC, suggesting that most medical providers don’t have knowledge and training about FGM/FC. The inadequate information on FGM/FC in medical textbooks reflects a culturally biased lack of recognition of the number of girls and women affected in the US. This maintains an ongoing pattern of silence that reinforces gender inequality. Considering the inadequate information covered in US medical textbooks on FGM/FC, and the concordant lack of provider training to provide advice and care to affected girls and women, incorrect and missed diagnoses may lead to harm to victims of FGM/FC. Providers would be better equipped to care for women and girls if their medical training included information regarding FGM/FC. 展开更多
关键词 Female Genital Mutilation Textbook Analysis
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基于遥感影像的峻河流域高寒灌丛决策树提取方法 被引量:2
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作者 王瑾 蔡演军 +1 位作者 梁福源 安芷生 《地球环境学报》 2010年第3期243-248,共6页
本文选择青海湖流域内一个具有代表性的小流域—峻河流域为研究对象,通过该区域IKNOS-2高分辨率影像的分析,发现该区域高寒灌丛的分布与海拔、坡度、坡向等因素密切相关。据此,将研究区1:5万DEM数据融入TM影像植被分类过程中,建立一种... 本文选择青海湖流域内一个具有代表性的小流域—峻河流域为研究对象,通过该区域IKNOS-2高分辨率影像的分析,发现该区域高寒灌丛的分布与海拔、坡度、坡向等因素密切相关。据此,将研究区1:5万DEM数据融入TM影像植被分类过程中,建立一种新的决策树分类方法,结果将分类总体精度提高到89.37%,Kappa系数提高到0.7875,达到一般分类结果的精度要求。这说明,加入多源数据,尤其是地形数据,能够显著提高高寒灌丛植被的分类精度。 展开更多
关键词 遥感影像 决策树 高寒灌丛 青海湖 峻河流域
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Mesoscale oceanic eddies in the South China Sea from 1992 to 2012:evolution processes and statistical analysis 被引量:3
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作者 DU Yunyan YI Jiawei +3 位作者 WU Di HE Zhigang WANG Dongxiao LIANG Fuyuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第11期36-47,共12页
Automated identification and tracking of mesoscale ocean eddies has recently become one research hotspot in physical oceanography. Several methods have been developed and applied to survey the general kinetic and geom... Automated identification and tracking of mesoscale ocean eddies has recently become one research hotspot in physical oceanography. Several methods have been developed and applied to survey the general kinetic and geometric characteristics of the ocean eddies in the South China Sea(SCS). However, very few studies attempt to examine eddies' internal evolution processes. In this study, we reported a hybrid method to trace eddies' propagation in the SCS based on their internal structures, which are characterized by eddy centers, footprint borders, and composite borders. Eddy identification and tracking results were represented by a GIS-based spatiotemporal model. Information on instant states, dynamic evolution processes, and events of disappearance, reappearance, split, and mergence is stored in a GIS database. Results were validated by comparing against the ten Dongsha Cyclonic Eddies(DCEs) and the three long-lived anticyclonic eddies(ACEs) in the northern SCS, which were reported in previous literature. Our study confirmed the development of these eddies. Furthermore, we found more DCE-like and ACE-like eddies in these areas from 2005 to 2012 in our database. Spatial distribution analysis of disappearing, reappearing, splitting, and merging activities shows that eddies in the SCS tend to cluster to the northwest of Luzon Island, southwest of Luzon Strait, and around the marginal sea of Vietnam. Kuroshio intrusions and the complex sea floor topography in these areas are the possible factors that lead to these spatial clusters. 展开更多
关键词 mesoscale eddies identification and tracking algorithms spatiotemporal model eddy splitting and merging South China Sea
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Synthesis of Niobium Doped ZnO Nanoparticles by Electrochemical Method: Characterization, Photodegradation of Indigo Carmine Dye and Antibacterial Study 被引量:1
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作者 Rakesh   Sannaiah Ananda +1 位作者 Netkal M. Made Gowda Kithanakere Ramesh Raksha 《Advances in Nanoparticles》 2014年第4期133-147,共15页
Niobium doped Zincoxide nanoparticles has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, IR Spectroscopy, SEM, XRD, ICPMS and EDAX data. The UV-Visible spectroscopy resul... Niobium doped Zincoxide nanoparticles has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, IR Spectroscopy, SEM, XRD, ICPMS and EDAX data. The UV-Visible spectroscopy result reveals that the band gap energy of ZnO/Nb2O5 nanoparticles to be 3.8 eV. The XRD results show that the crystallite size is to be 31.9 nm. The ICPMS data indicate the presence of 3,3461,328 counts of 93 Nb and 577,906,390 counts of 66 Zn. An improvement in the photocatalytic degradation of Indigocarmine dye (IC) in comparison to commercially available pure ZnO was observed. The photodegradation efficiency for ZnO/Nb2O5 and ZnO were found to be 97.4% and 52.1% respectively. The enhancement in photocatalytic activity of ZnO/ Nb2O5 was ascribed to the extended light absorption range and suppression of electron hole pair recombination upon Nb loading. The antibacterial activity of ZnO/Nb2O5 nanoparticles was investigated. These particles were shown to have an effective bactericide. 展开更多
关键词 ZnO/Nb2O5 NANOPARTICLES Electrochemical Method NIOBIUM Coated Platinum Electrode (Pt/Nb) INDIGO CARMINE DYE (IC) E. coli
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Office Information Systems: A Retrospective and a Call to Arms 被引量:1
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作者 Chandra S. Amaravadi 《Journal of Software Engineering and Applications》 2014年第8期700-712,共13页
Office Information Systems is a field of computer science concerned with studying offices and developing technologies to support office workers. The field initiated in 1982 suffered a gradual demise by 2004. However, ... Office Information Systems is a field of computer science concerned with studying offices and developing technologies to support office workers. The field initiated in 1982 suffered a gradual demise by 2004. However, many of the themes and issues that motivated the discipline continue to exist today. Office workers continue to struggle with routine tasks that do not have adequate IT support and the problem is worse for mobile employees. In this paper we provide a retrospective on OIS technologies with the hope of stimulating interest in the discipline and addressing the needs of office workers worldwide. The evolution of office technologies and a detailed discussion of past research are provided. The discussion shows that technology support for office workers is still inadequate. The paper suggests a technology vision and architecture to motivate researchers and identifies challenges for future research. 展开更多
关键词 OIS OFFICE Information SYSTEMS OFFICE SYSTEMS OFFICE Automation WORKFLOW EVOLUTION of OFFICE SYSTEMS EVOLUTION of OIS OFFICE PROCEDURES OFFICE Processes OFFICE Technologies
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ANALYSIS AND IMPROVEMENT OF LEAD TIME FOR JOB SHOP UNDER MIXED PRODUCTION SYSTEM 被引量:1
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作者 CHE Jianguo HE Zhen EDWARD M Knod 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期487-491,共5页
Firstly an overview of the potential impact on work-in-process (WIP) and lead time is provided when transfer lot sizes are undifferentiated from processing lot sizes. Simple performance examples are compared to thos... Firstly an overview of the potential impact on work-in-process (WIP) and lead time is provided when transfer lot sizes are undifferentiated from processing lot sizes. Simple performance examples are compared to those from a shop with one-piece transfer lots. Next, a mathematical programming model for minimizing lead time in the mixed-model job shop is presented, in which one-piece transfer lots are used. Key factors affecting lead time are found by analyzing the sum of the longest setup time of individual items among the shared processes (SLST) and the longest processing time of individual items among processes (LPT). And lead time can be minimized by cutting down the SLST and LPT. Reduction of the SLST is described as a traveling salesman problem (TSP), and the minimum of the SLST is solved through job shop scheduling. Removing the bottleneck and leveling the production line optimize the LPT. If the number of items produced is small, the routings are relatively short, and items and facilities are changed infrequently, the optimal schedule will remain valid. Finally a brief example serves to illustrate the method. 展开更多
关键词 Lead time Work-in-process(WIP) Mixed production system Job shop scheduling problem Traveling salesman problem(TSP)
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Synthesis of Chromium(III) Oxide Nanoparticles by Electrochemical Method and Mukia Maderaspatana Plant Extract, Characterization, KMnO<sub>4 </sub>Decomposition and Antibacterial Study 被引量:1
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作者 Rakesh   S. Ananda Netkal M. Made Gowda 《Modern Research in Catalysis》 2013年第4期127-135,共9页
Chromium oxide nanoparticles were synthesized by the reduction of potassium dichromate solution with Mukia Maderaspatana plant extract. In electrochemical methods, Cr2O3 nanoparticles were synthesized by two ways, usi... Chromium oxide nanoparticles were synthesized by the reduction of potassium dichromate solution with Mukia Maderaspatana plant extract. In electrochemical methods, Cr2O3 nanoparticles were synthesized by two ways, using platinum (Pt) electrodes and K2Cr2O7 solution with H2SO4 as medium in the first case. And chromium doped platinum electrode (Pt/Cr) in presence of NaHCO3 solution in second case. The resulting Cr2O3 nanoparticles were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV-VIS absorption and Fourier-transform infrared (FTIR) spectroscopy. The enhancing influence of Cr2O3 nanoparticles as a catalyst for the decomposition of KMnO4 has been studied. The antibacterial effect of Cr2O3 nanoparticles against E. coli was investigated. These particles were shown to have an effective bactericide. 展开更多
关键词 Potassium DICHROMATE Solution CR2O3 Nanoparticles CHROMIUM Doped Platinum Electrode (Pt/Cr) E. coli
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Moderating variables in the relationship between mental toughness and performance in basketball
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作者 Aubrey Newland Maria Newton +2 位作者 Laura Finch Colin R.Harbke Leslie Podlog 《Journal of Sport and Health Science》 SCIE 2013年第3期184-192,共9页
Purpose: This study explored the relationship between mental toughness and college basketball performance, specifically examining possible moderating variables (gender and starting status). Methods: Male and fema... Purpose: This study explored the relationship between mental toughness and college basketball performance, specifically examining possible moderating variables (gender and starting status). Methods: Male and female (n = 197) college basketball players completed the Psychological Performance Inventory-Alternative (PPI-A), a measure of characteristics and skills consistent with mental toughness, and the PERK an objective measure of basketball performance. Results: Findings suggest that basketball performance can be partially predicted by mental toughness and starting status. Males reported greater mental toughness than females. Starters and nonstarters did not differ in mental toughness. Moderated hierarchical regression analysis indicated that mental toughness was related to performance for male players as both a main effect and interaction with starter status. For female players, in contrast, starter status was the only significant predictor of performance. Practitioners are encouraged to foster the psychological skills associated with mental toughness in females and non-starters in basketball. Conclusion: Discussion of the PPI-A as a measure of mental toughness and suggestions for its improvement are explored. A need exists for additional research on mental toughness and objective performance, as performance enhancement is a major impetus for research on mental toughness. Copyright @ 2012, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved. 展开更多
关键词 BASKETBALL Mental toughness Moderating variables PERFORMANCE Psychological Performance Inventory-Alternative Psychological skills
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Synthesis of Iron-Pyridoxine Complex by Solvothermal Process, Its Structural Characterization and Antioxidant Activity Evaluation
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作者 Girigowda Chaitanya Lakshmi Sannaiah Ananda Netkal Made Gowda Made Gowda 《Journal of Chemistry and Chemical Engineering》 2010年第12期33-37,共5页
Hydroxyl radicals, superoxide anions and nitricoxide radicals are reactive species that can attack biomolecules such as DNA, lipids and proteins to cause many lifestyle-related diseases including hypertension and phot... Hydroxyl radicals, superoxide anions and nitricoxide radicals are reactive species that can attack biomolecules such as DNA, lipids and proteins to cause many lifestyle-related diseases including hypertension and photoaging. This study reports the synthesis of new copper-pyridoxine and iron-pyridoxine complexes. The complexes have been synthesized and characterized by molar conductances, IR, UV-Visible, mass spectrometry, melting points and magnetic moment datas. The molecular formula of the complex is found to be Fe(py ^-)2Cl.H2O. The pyH/pyligand is coordinated to copper and iron through N atom of the pyridine ring and O atom of 5'-CH2OH group. The Fe(III) complex is found to be paramagnetic with one unpaired electron. The antioxidant activities of the free ligand and its complexes were determined in vitro. 展开更多
关键词 Pyridoxine-metal complexes PYRIDOXINE transition metals antioxidant activity mass spectrometry.
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Nano-Microencapsulation and Controlled Release of Linoleic Acid in Biopolymer Matrices: Effects of the Physical State, Water Activity, and Quercetin on Oxidative Stability
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作者 Gilles K. Kouassi Vinod K. Teriveedhi +4 位作者 Christopher L. Milby Tarab Ahmad Mark S. Boley Netkal M. Gowda Ronald J. Terry 《Journal of Encapsulation and Adsorption Sciences》 2012年第1期1-10,共10页
In this study, linoleic acid (LA) was encapsulated in the presence or absence of quercetin into a dual polymer system of whey protein and kappa-carrageenan using power ultrasound. Atomic Force Microscopy (AFM) and Flo... In this study, linoleic acid (LA) was encapsulated in the presence or absence of quercetin into a dual polymer system of whey protein and kappa-carrageenan using power ultrasound. Atomic Force Microscopy (AFM) and FlowCam imaging technology were used for imaging and size determination of nano-and micro-capsules. Differential scanning calorimeter (DSC) was used to determine the glass transition temperature (Tg) of the freeze-dried nanocapsules. In order to examine the effect of water activity (aw) on the release profile of the encapsulated LA, the nanocapsules were equilibrated over saturated salt solution conditions corresponding to the range of aw between 0.333 and 0.769 in evacuated desiccators at room temperature. Gravimetric measurements of the steady state linoleic acid (LA) contents were conducted. The anti-oxidant activity of quercetin and the stability of encapsulated LA toward long term and thermally induced rancidity was investigated. The capsules were in the nanosize regime and 83% of the LA was effectively encapsulated. Furthermore, at aw of 0.764, the highest percentage of LA (74%) was released from the expelling nanocapsules. Quercetin was found to exhibit protective antioxidant effect against time-dependent oxidation and thermally induced rancidity of LA. Water activity values of 0.662 and 0.764 provided ideal humidity and pressure conditions for sustained release of nanoencapsulated LA at room temperature. 展开更多
关键词 NANOENCAPSULATION MICROENCAPSULATION KAPPA-CARRAGEENAN QUERCETIN RANCIDITY ANTIOXIDANT
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Kinetic and Mechanistic Study of Oxidation of Piperazines by Bromamine-T in Acidic Medium
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作者 Chandrashekar   B. M. Venkatesha +1 位作者 S. Ananda Netkal M. Made Gowda 《Modern Research in Catalysis》 2013年第4期157-163,共7页
Oxidations of piperazine, 1-methylpiperazine and 1-ethylpiperazine by bromamine-T (BAT) in buffered acidic medium have been kinetically studied at 303 K. The reaction shows a first-order dependence of the rate each on... Oxidations of piperazine, 1-methylpiperazine and 1-ethylpiperazine by bromamine-T (BAT) in buffered acidic medium have been kinetically studied at 303 K. The reaction shows a first-order dependence of the rate each on [BAT]0 and [piperazine]0, and an inverse fractional-order dependence on [H+]. The additions of halide ions and the reduction product of BAT, p-toluenesulfonamide, have no effect on the reaction rate. The variation of ionic strength of the solvent medium has no influence on the rate. Activation parameters have been evaluated from the Arrhenius and Eyring plots. A common mechanism consistent with the kinetic data has been proposed for all piperazines. The protonation constants of substrates have been evaluated. The Hammett linear free-energy relationship has been observed for the reaction with ρ = ?0.5 indicating that the electron-donating groups enhance the reaction rate by stabilizing the transition state. An isokinetic relationship observed shows β = 368 K indicating the dominance of enthalpy factors on the reaction rate. 展开更多
关键词 PIPERAZINES OXIDATION KINETICS MECHANISM Bromamine-T BUFFER
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The Grand Challenges in Information Systems
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作者 Chandra Amaravadi 《Journal of Software Engineering and Applications》 2022年第4期103-115,共13页
The field of information systems has historically suffered from a pre-dominance of behavioral approaches. As a result, it is not surprising that in spite of decades of research, dozens of conferences and journals and ... The field of information systems has historically suffered from a pre-dominance of behavioral approaches. As a result, it is not surprising that in spite of decades of research, dozens of conferences and journals and thousands of researchers, very few breakthroughs have been achieved. This paper advocates a technical approach that focuses on improving existing systems in organizations by viewing them from the point of roles i.e. functions fulfilled by IS in organizations. These are understood as: 1) supporting operations, 2) providing information, 3) supporting decision making, 4) providing knowledge, 5) supporting knowledge and clerical work, and 6) supporting organizational design. It is generally agreed that the field’s understanding of fulfilling roles “1”, “2”, “3” and “6” is mature while understanding of areas “3” (for unstructured decisions), “4”, and “5” are still incomplete. The challenges in these areas are difficult problems that we refer to as grand challenges and discuss in this paper. 展开更多
关键词 Challenges in Information Systems Information Systems Challenges Research in IS IS Research Technology Support
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Hacked by Bits and Pieces: What Can We Learn from an Example of Corporate Espionage?
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作者 Jack Schafer Marvin Karlins 《Journal of Information Security》 2021年第3期224-231,共8页
Information security often involves the development and application of so</span><span style="font-family:Verdana;">phisticated software to protect sensitive information stored in corporate</sp... Information security often involves the development and application of so</span><span style="font-family:Verdana;">phisticated software to protect sensitive information stored in corporate</span><span style="font-family:Verdana;"> computers. Yet, in this example of corporate espionage, a clever person, a cellphone and some readily available software were all it took to crack through one company’s advanced security barriers. By reading this article it is hoped that employees at all levels of an organization’s hierarchy will become more aware of—and recognize—how: 1) bits and pieces of seemingly harmless and easy-to-acquire information can be used for sinister purposes;2) building rapport and trust with a person can make them more likely to become unknowing co-conspirators in a devious undertaking;and 3) how one must be constantly alert not to give out information without carefully considering the authenticity and justification of the source requesting it. 展开更多
关键词 Cyber Security HACKING Social Engineering Scams Corporate Espionage
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Developing New Applications Based on Laser Additive Manufacturing of WC Cermets and WC Forming Alloys (Invited Paper) 被引量:3
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作者 James W.Sears 《中国激光》 EI CAS CSCD 北大核心 2009年第12期3245-3250,共6页
Laser additive manufacturing(LAM) of tungsten carbide metal matrix composites(MMCs) has been evaluated for surface modification of hot die forming tools,cutting edges,glass tooling,extrusion mandrels,and other abrasiv... Laser additive manufacturing(LAM) of tungsten carbide metal matrix composites(MMCs) has been evaluated for surface modification of hot die forming tools,cutting edges,glass tooling,extrusion mandrels,and other abrasive wear applications.This work focuses on transitions from tool steels to MMCs through a single pass laser powder deposition operation.Issues related to the application of various metal powders and carbides used include surface hardness,porosity,cracking,and dilution.These issues along with factory results that were obtained during this project are discussed. 展开更多
关键词 激光添加剂 碳化钨 工具钢 金属基复合材料
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A Review on Self-healing in Modern Power Distribution Systems 被引量:2
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作者 Seyed Ali Arefifar Md Shahin Alam Abdullah Hamadi 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2023年第6期1719-1733,共15页
The ever-increasing dependence on electrical power has posed more challenges to power system engineers to deliver secure, stable, and sustained energy to electricity consumers. Due to the increasing occurrence of shor... The ever-increasing dependence on electrical power has posed more challenges to power system engineers to deliver secure, stable, and sustained energy to electricity consumers. Due to the increasing occurrence of short-and long-term power interruptions in the power system, the need for a systematic approach to mitigate the negative impacts of such events is further manifested. Self-healing and its control strategies are generally accepted as a solution for this concern. Due to the importance of self-healing subject in power distribution systems, this paper conducts a comprehensive literature review on self-healing from existing published papers. The concept of self-healing is briefly described, and the published papers in this area are categorized based on key factors such as self-healing optimization goals, available control actions, and solution methods. Some proficient techniques adopted for self-healing improvements are also classified to have a better comparison and selection of methods for new investigators. Moreover, future research directions that need to be explored to improve self-healing operations in modern power distribution systems are investigated and described at the end of this paper. 展开更多
关键词 SELF-HEALING distributed generator renewable energy source MICROGRID OPTIMIZATION RECONFIGURATION service restoration automation system
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Human’s digital footprints on the Qinghai-Tibet Plateau:Variations during festivals and impacts on nature reserves 被引量:1
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作者 DU Yunyan TU Wenna +1 位作者 LIANG Fuyuan YI Jiawei 《Journal of Geographical Sciences》 SCIE CSCD 2021年第2期179-194,共16页
Mobile internet and wireless communication technologies have produced unprecedented location-aware data.Such big geospatial data can be used as a proxy measure of the‘digital footprints’left by us on the planet and ... Mobile internet and wireless communication technologies have produced unprecedented location-aware data.Such big geospatial data can be used as a proxy measure of the‘digital footprints’left by us on the planet and provide a valuable opportunity to understand the dynamic and short-term human disturbance on the nature at fine scales.This study investigated the spatiotemporal variations of human’s digital footprints on the Qinghai-Tibet Plateau using smartphone-users-generated Tencent’s location request data.The results showed that human’s digital footprints cover less than 5%of Qinghai and Tibet,exhibiting either a U-shaped or an N-shaped temporal change pattern during the major festivals.Spatial changes of the digital footprints manifested a transition process from dispersion to concentration in Xining and Lhasa.Human disturbance assessment of seven large nature reserves on the plateau showed that the Qinghai Lake is the most disturbed one as shown by 14.6%of its area is stained with human digital footprints and the areal average of footprint intensity is 1.59,and the disturbance was significantly escalated during the National Day holiday.By contrast,the Qangtang and Hoh Xil are the least affected nature reserves with the two indices less than 1%and 0.1,respectively. 展开更多
关键词 digital footprint space-time variations human impact nature reserve location request
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A quantitative morphometric comparison of cockpit and doline karst landforms 被引量:4
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作者 LIANG Fuyuan DU Yunyan +1 位作者 GE Yong LI Ce 《Journal of Geographical Sciences》 SCIE CSCD 2014年第6期1069-1082,共14页
This study presented a quantitative comparison of cockpit and doline karst by examining the numbers and characteristics of typical types of landform entities that are developed in Guilin(Guangxi, China), La Alianza... This study presented a quantitative comparison of cockpit and doline karst by examining the numbers and characteristics of typical types of landform entities that are developed in Guilin(Guangxi, China), La Alianza(PR, USA), Avalton(KY, USA), and Oolitic(IN, USA). Five types of landform entities were defined: isolated hill(IH), clustered hills(CHs), isolated sinkhole(IS), clustered sinkholes(CSs), and clustered hills with sinkholes(CHSs). An algorithm was developed to automatically identify these types of landform entities by examining the contour lines on topographic maps of two cockpit karst areas(Guilin and La Alianza) and two doline karst areas(Oolitic and Avalton). Within each specific study area, the CHSs is the least developed type yet with a larger size and higher relief. The IH and IS entities are smaller in size, lower in relief, and outnumber their clustered counterparts. The total numbers of these types of entities are quite different in cockpit and doline karst areas. Doline karst is characterized by more negative(IS and CSs) than positive(IH and IHs) landforms and vice versa for cockpit karst. For example, the Guilin study area has 1192 positive landform entities in total, which occupy 9.81% of the total study area. It has only 622 negative landform entities occupying only 3.91% of the total study area. By contrast, the doline karst in Oolitic has 130 negative while only 10 positive landform entities. The positive and negative landforms in Oolitic occupy 12.68% and 2.61% of the total study area, respectively. Furthermore, average relief and slope of the landform entities are much higher and steeper in the cockpit karst than the doline karst areas. For instance, the average slope of CHs in Alvaton is 3.90 degrees while it is 19.78 degrees in La Alianza. The average relief of CSs is 4.07 m and 34.29 m in Oolitic and Guilin respectively. Such a difference within a specific area or between the cockpit and doline karst may reveal different controls on the development of karst landscape. 展开更多
关键词 cockpit doline contours morphometric characteristics topographic map karst
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Quantitative estimates of collective geo-tagged human activities in response to typhoon Hato using location-aware big data 被引量:1
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作者 Zhang Liu Yunyan Du +3 位作者 Jiawei Yi Fuyuan Liang Ting Ma Tao Pei 《International Journal of Digital Earth》 SCIE 2020年第9期1072-1092,共21页
Location-aware big data from social media have been widely used to quantitatively characterize natural disasters and disaster-induced losses.It is not clear how human activities collectively respond to a disaster.In t... Location-aware big data from social media have been widely used to quantitatively characterize natural disasters and disaster-induced losses.It is not clear how human activities collectively respond to a disaster.In this study,we examined the collective human activities in response to Typhoon Hato at multi spatial scales using aggregated location request data.We proposed a Multilevel Abrupt Changes Detection(MACD)methodological framework to detect and characterize the abrupt changes in location requests in response to Typhoon Hato.Results show that,at the grid level,most anomaly grids were located within a radius of 53 km around the typhoon trajectory.At the city level,there are significant spatial difference in terms of the human activity recovery duration(230 h on average).At the subnational level,the absolute magnitude of abrupt location request changes is strongly correlated with the typhoon-induced economic losses and the population affected. 展开更多
关键词 Human response TYPHOON natural disaster locationaware data rapid disaster assessment
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Stochastic SIS metapopulation models for the spread of disease among species in a fragmented landscape
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作者 Amy J. Ekanayake 《International Journal of Biomathematics》 2016年第4期97-119,共23页
Two stochastic models are derived for a susceptible-infectious-susceptible epidemic spreading through a metapopulation: a continuous time Markov chain (CTMC) model and an It6 stochastic differential equation (SDE... Two stochastic models are derived for a susceptible-infectious-susceptible epidemic spreading through a metapopulation: a continuous time Markov chain (CTMC) model and an It6 stochastic differential equation (SDE) model. The stochastic models are numerically compared. Close agreement suggests that computationally intense CTMC simulations can be approximated by simpler SDE simulations. Differential equations for the moments of the SDE probability distribution are also derived, the steady states are solved numerically using a moment closure technique, and these results are compared to simulations. The moment closure technique only coarsely approximates simulation results. The effect of model parameters on stability of the disease-free equilibrium is also numerically investigated. 展开更多
关键词 EPIDEMIC METAPOPULATION Ito stochastic differential equation Markov chain moment closure.
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