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International Journal of Disaster Risk Science 2024年第5期15卷 673-687页

作者： Kristine Steen-Tveit Bj?rn Erik Munkvold Kjetil Rustenberg Department of Information Systems Centre for Integrated Emergency ManagementUniversity of Agder

This study investigated the crucial role of formulating and applying standard operating procedures(SOPs) in the context of emergency planning and response. The effective application of SOPs during operations is essential in order to address challenges that surpass individual organizational capacities. A specific focus on fostering efficient information sharing and executing specified actions maximizes the prospect of success. To explore the collective functionality of SOPs across organizations, we conducted a comprehensive tabletop exercise involving 10 organizations spanning tactical, operational,and strategic levels. Our analysis identified six key challenges, primarily related to the structures for information sharing,communication pathways, and the complex integration and application of common SOPs within these diverse organizational contexts. This research contributes insights into the use of SOPs in large-scale, cross-organizational scenarios.

关键词： Cross-organizational emergency management Standard operating procedures Tabletop exercise Team situational awareness

Nitrogen Mineralization in Soils Along a Vegetation Chronosequence in Hong Kong

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Pedosphere 2005年第2期15卷 181-188页

作者： L.M.MARAFA K.C.CHAU centre for Environmental Policy and Resource management Centre for Environmental Policy and Resource Management Department of Geography and Resource ManagementThe Chinese University of Hong KongShatinNew TerritoriesHong Kong (China)Department of Geography and Resource ManagementThe Chinese University of Hong KongShatinNew TerritoriesHong Kong (China)

This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the relationships between N mineralization and successional development of vegetation in the absence of fire. The sites including a newly burnt area (S1), short grassland (S2), tall grassland (S3), mixed tall grassland and shrubland (S4), and woodland (S5) were selected,and the in situ core incubation method was used to estimate nitrogen mineralization. Throughout the 60-day incubation in four periods, more nitrogen was mineralized at the S3 and S4 sites, the predominantly grassland sites, which contained the highest levels of soil organic matter (SOM) and total Kjeldahl nitrogen (TKN), than the S1 site, while immobilization occurred at the S2 and S5 sites. Leaching loss decreased with successional development of the vegetation, in the order of S1 ＞ S2 ＞ S3 ＞ S4 ＞ S5. The pattern of nitrogen uptake with ecological succession was less conspicuous, being complicated by the immediate effect of fire and possibly the ability of the woodland species to extract nitrogen from the deeper *** the absence of fire for 3 to 6 years, the build-up of SOM and TKN was accompanied by active mineralization, thus paving the way for the invasion of shrub and tree species. A close relationship existed between nitrogen mineralization and ecological succession with this vegetation gradient. Inherent mechanisms to preserve nitrogen in a fire-prone environment including immobilization and uptake and the practical relevance of nitrogen mineralization to reforestation are discussed.

关键词： fire impact immobilization nitrogen mineralization successional development vegetation chronosequence

Molecular characterization of DENV-3 circulating during the post-monsoon period of 2013–14 in Delhi, India

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Virologica Sinica 2015年第6期30卷 464-469页

作者： Pankaj Sharma Veena Mittal Mala Chhabra Roop Kumari Priyanka Singh Dipesh Bhattacharya Srinivas Venkatesh Arvind Rai Division of Zoonosis National Centre for Disease Control centre for Medical Entomology and Vector management National Centre for Disease Control Division of Biotechnology National Centre for Disease Control

Dear Editor,Dengue infection is one of the emerging concerns for public health on a global *** the past few years,dengue transmission has increased in the Americas,the western Pacific and southeast *** magnitude,distribution,and clinical severity of dengue outbreaks have been an alarming signal in the southeast Asia *** outbreaks have been reported in countries in

关键词： southeast dengue India circulating monsoon in Delhi severity sequenced Major emerging

Analysis of Differences in Productivity,Profitability and Soil Fertility Between Organic and Conventional Cropping Systems in the Tropics and Sub-tropics

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Journal of Integrative Agriculture 2014年第10期13卷 2299-2310页

作者： Te Pas C M Rees R M School of GeoSciences University of Edinburgh Carbon management centre Scotland's Rural College

Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conventional fanning because it ensures higher biodiversity, restricts environmental pollution, prevents land degradation and is easy to apply for smallholder and subsistence farmers. Although widely practiced and studied in temperate regions, little is known about the potential overall benefits of organic farming in the tropics and subtropics. This paper addresses this gap by undertaking an analysis of the differences between organic and conventional agriculture in the tropics and sub-tropics based on an extensive literature review including 88 papers with 458 data pairs. The comparison is based on three main indicators： yield, gross margin and soil organic carbon （SOC）. The differences between the organic and conventional systems for each of these main indicators is represented by the ratio of the value of the indicator in the organic system divided by the corresponding value in the conventional system. This was initially calculated for each data pair individually, and grouped by a variety of explanatory factors, such as precipitation, human development level, soil texture, crop type, organic input type, time after conversion and certification. The results demonstrate that under organic management, yields were on average 26% higher, gross margins 51% higher and soil organic carbon 53% higher than under conventional management. The highest yield increases in organic cropping systems were achieved in the least developed countries, in arid regions and on coarse soils. For gross margins, certification was the main reason for differences between organic and conventional systems. Certified farmers, mostly located in developed countries, receive significantly higher prices. Furthermore, organic farming in the driest regions results in higher profits than in other

关键词： organic farming conventional fanning tropics subtropics carbon sequestration yield soil quality soil organic carbon

Perceived Adverse Effects of Separating Government Institutions for Disaster Risk Reduction and Climate Change Adaptation Within the Southern African Development Community Member States

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International Journal of Disaster Risk Science 2021年第1期12卷 1-12页

作者： Livhuwani D.Nemakonde Dewald Van Niekerk Per Becker Sizwile Khoza African centre for Disaster Studies Unit for Environmental Sciences and ManagementNorth-West UniversityPotchefstroom 2522South Africa Lund University centre for Risk Assessment and management(LUCRAM) Lund University22100 LundSweden

Integration of disaster risk reduction(DRR)and climate change adaptation(CCA)is widely recognized as a solution for reducing the risk and impacts of ***,successful integration seems elusive,and the two goals continue to function in isolation and in *** article provides empirical insights into the perceived effects of separating government institutions for DRR and CCA within the Southern African Development Community member states.A mixed method research design was applied to the study.A total of 40 respondents from Botswana,Eswatini(until April 2018 Swaziland),Madagascar,Malawi,Namibia,South Africa,Tanzania,Zambia,and Zimbabwe participated in face-to-face interviews or an online *** major effects of separating the organizations for DRR and CCA that impede efforts to reduce disaster risk coherently were identified:duplication of services,polarization of interventions,incoherent policies,competition for the same resources,and territorial *** the continued fragmentation of institutions for DRR and CCA,highlighting these effects is important to emphasize the need for integrated approaches towards the reduction of disaster risk.

关键词： Climate change adaptation Disaster risk reduction Southern African Development Community Sustainable development

Identification and control of a small-scale helicopter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第12期11卷 978-985页

作者： Abdelhakim DEBOUCHA Zahari TAHA centre for Product Design and Manufacturing University of Malaya Faculty of Manufacturing Engineering and management Technology University Malaysia Pahang

Designing reliable flight control for an autonomous helicopter requires a high performance dynamics *** this paper,a nonlinear autoregressive with exogenous inputs (NLARX) model is selected as the mathematical structure for identifying and controlling the flight of a small-scale helicopter.A neural network learning algorithm is combined with the NLARX model to identify the dynamic component of the rotorcraft unmanned aerial vehicle (RUAV).This identification process is based on the well-known gradient descent learning *** a case study,the multiple-input multiple-output (MIMO) model predictive control (MPC) is applied to control the pitch motion of the *** of the neural network output model are closely match with the real flight *** MPC also shows good performance under various conditions.

关键词： Dynamics model System identification Black box Small-scale helicopter Neural networks (NNs) Control design

Impregnation of carbonaceous nanofibers into glassy polymer-based composite membrane for CO_2 separation

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2385-2390页

作者： Pannir Selvam Murugiah Pei Ching Oh Kok Keong Lau CO_2 Research centre Institute of Contaminant ManagementChemical Engineering DepartmentUniversiti Teknologi PETRONAS

The development of defect-free composite membrane(CM) is often challenging due to poor dispersion and distribution of filler particles in the polymer matrix. Despite the attractive physicochemical properties and gas separation performance of carbon nanotube(CNT) based CM, CNT displayed poor dispersion characteristics in most polymer matrix domain. Instead of incorporating CNT, a viable alternative, carbon nanofiber(CNF) which exhibits similar properties as CNT, but improved dispersion quality in the polymer matrix is found. In this work,CNF particles were incorporated in poly(2,6-dimethyl-1,4-phenylene oxide)(PPOdm) polymer continuous phase for CM development. The optimum gas separation performance of the PPOdm-CNF CM(11.25 at 197.02 barrer of CO_2 permeability) was obtained at 3 wt% of CNF loading. Compared to pristine PPOdmmembrane,CO_2 permeability and CO_2/CH_4 selectivity of PPOdm-3 wt% CNF CM were enhanced by 180% and 55%, *** 3 wt% CNF loading, the filler particles were dispersed and distributed more homogenously, in which no obvious CNF agglomeration was observed. In addition, the incorporation of CNF particles also enhanced the mechanical and thermal properties of the resultant CM.

关键词： Carbon nanofiber Composite membrane Carbon dioxide Gas separation

Performance study of selective encryption in comparison to full encryption for still visual images

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第6期15卷 435-444页

作者： Osama A.KHASHAN Abdullah M.ZIN Elankovan A.SUNDARARAJAN centre for Software Technology and management Faculty of Information Science and TechnologyNational University of Malaysia (UKM)

Securing digital images is becoming an important concern in today's information security due to the extensive use of secure images that are either transmitted over a network or stored on disks. Image encryption is the most effective way to fulfil confidentiality and protect the privacy of images. Nevertheless, owing to the large size and complex structure of digital images, the computational overhead and processing time needed to carry out full image encryption prove to be limiting factors that inhibit it of being used more heavily in real time. To solve this problem, many recent studies use the selective encryption approach to encrypt significant parts of images with a hope to reduce the encryption overhead. However, it is necessary to realistically evaluate its performance compared to full encryption. In this paper, we study the performance and efficiency of image segmentation methods used in the selective encryption approach, such as edges and face detection methods, in determining the most important parts of visual images. Experiments were performed to analyse the computational results obtained by selective image encryption compared to full image encryption using symmetric encryption algorithms. Experiment results have proven that the selective encryption approach based on edge and face detection can significantly reduce the time of encrypting still visual images as compared to full encryption. Thus, this approach can be considered a good alternative in the implementation of real-time applications that require adequate security levels.

关键词： Selective image encryption Edge detection Face detection

Knowledge discovery for geographical cellular automata

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Science China Earth Sciences 2005年第10期48卷 1758-1767页

作者： Anthony Gar-On Yeh centre of Urban Planning and Environmental management The University of Hong Kong Hong Kong SAR China

This paper proposes a new method for geographical simulation by applying data mining techniques to cellular automata. CA has strong capabilities in simulating complex systems. The core of CA is how to define transition rules. There are no good methods for defining these transition rules. They are usually defined by using heuristic methods and thus subject to uncer-tainties. Mathematical equations are used to represent transition rules implicitly and have limita-tions in capturing complex relationships. This paper demonstrates that the explicit transition rules of CA can be automatically reconstructed through the rule induction procedure of data mining. The proposed method can reduce the influences of individual knowledge and preferences in de-fining transition rules and generate more reliable simulation results. It can efficiently discover knowledge from a vast volume of spatial data.

关键词： knowledge discovery, cellular automata, geographical simulation, geographical information systems.

Fundamental definitions and calculation rules of grey mathematics: a review work

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1254-1267页

作者： Qiaoxing Li Sifeng Liu Jeffrey Yi-Lin Forrest School of management Guizhou University School of Economics and management Nanjing University of Aeronautics and Astronautics centre of Computational Intelligence De Montfort University School of Business Slippery Rock University

Grey mathematics is the mathematical foundation of the grey system theory. Recently, some important results have been achieved. In order to accelerate the development of grey mathematics, the results are summarized and redefined. This paper includes the fundamental definitions and calculation rules of the grey hazy set, grey number, grey matrix and grey function. Grey mathematics includes four types of operation, i.e. the grey operation, the whitened operation, the covered operation and the only potential true operation. According to its intrinsic quality, the covered operation, which differs from the interval one, is called as the whole-proximate calculation that means the proximate calculation spreads through the whole range of the covered set of every grey number, and we confirm that it may be a new branch of computational or applied mathematics. The overview should develop the grey system theory and grey mathematics.

关键词： grey mathematics grey hazy set grey number covered operation grey system theory.