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Determination of the ground vibration attenuation law from a singleblast: A particular case of trench blasting

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第5期13卷 1182-1192页

作者： rafael Rodríguez Laura García de Marina Marc Bascompta Cristóbal Lombardía Department of Mining Exploitation and Prospecting School of MiningEnergy and Materials EngineeringUniversity of OviedoIndependencia 13Oviedo33004Spain Department of Mining Industrial and ICT EngineeringPolytechnic University of Catalonia(UPC)ManresaAv.Bases de Manresa61-73Barcelona08242Spain Perforaciones Noroeste S.A Longoria Carbajal No.3Oviedo33004Spain

The general transmissivity law of ground vibrations was studied,and a user-friendly methodology for determining the behavior of vibrations generated in any rock mass is *** study was based on a single blast in a trench excavation,analyzing the vibration components recorded from two fixed *** attenuation law and the main variables according to the legal requirements,frequency and peak particle velocity(PPV),are defined with this novel method,achieving a high confidence level in a simple *** proposed approach can also have an important impact in terms of reducing the potential consequences of vibrations for the surrounding construction and achieving the required definition of rock *** the cost and time in many projects where blasting techniques are applied is particularly useful for the design of future blasts.

关键词： Empirical analysis Blasting Ground vibration Trenching Wave propagation

An assessment of African lion Panthera leo sociality via social network analysis： prerelease monitoring for an ex situ reintroduction program

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Current Zoology 2017年第3期63卷 301-311页

作者： Emma J. DUNSTON Jackie ABEL Rebecca E. DOYLE Jacqui KIRK Victoria B. HILLEY Andrew FORSYTH Emma JENKINS rafael FREIRE School of Animal and Veterinary Sciences Charles Sturt University Wagga Wagga NSW 2678 Australia Social and Conservation Psycology Coventry University Coventry CV1 5FB UK African Lion & Environmental Research Trust Melrose Farm Livingstone 23345 Zambia Animal Welfare Science Centre The University of Melbourne Parkville Victoria 3010 Australia African Lion & Environmental Research Trust Antelope Park Gweru Midlands Zimbabwe Siyafunda The Greater Makalali Private Game Reserve Harmony 27 Hoedspruit 0895 South Africa

The wild population of the African lion Panthera leo continues to decline, requiring alternate conservation programs to be considered. One such program is ex situ reintroduction. Prior to release, longterm monitoring and assessment of behavior is required to determine whether prides and coalitions behave naturally and are sufficiently adapted to a wild environment. Social network analysis （SNA） can be used to provide insight into how the pride as a whole and individuals within it, function. Our study was conducted upon 2 captive-origin prides who are part of an ex situ reintroduction program, and 1 wild pride of African lion. Social interactions were collected at all occurrence for each pride and categorized into greet, social grooming, play, and aggression. Betweenness centrality showed that offspring in each pride were central to the play network, whereas degree indicated that adults received （indegree） the greatest number of overall social interactions, and the adult males of each pride were least likely to initiate （outdegree） any interactions. Through the assessment of individual centrality and degree values, a social keystone adult female was identified for each pride. Social network results indicated that the 2 captive-origin prides had formed cohesive social units and possessed relationships and behaviors comparable with the wild pride for the studied behaviors. This study provided the first SNA comparison between captive-bred origin and a wild pride of lions, providing valuable information on individual and pride sociality, critical for determining the success of prides within an ex situ reintroduction program.

关键词： African lion Panthera leo conservation ex situ reintroduction social interactions.

Retention of eucalyptus harvest residues reduces soil compaction caused by deep subsoiling

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Journal of Forestry Research 2022年第2期33卷 643-651页

作者： Raphael Oliveira de Melo AymbiréAngeletti da Fonseca Nairam Félix de Barros Raphael Bragança Alves Fernandes rafael da Silva Teixeira Iago Nery Melo Ricardo Previdente Martins Soil Science Department Universidade Federal de ViçosaViçosaMinas GeraisBrazil BRACELL company AlagoinhasBahiaBrazil

Eucalyptus harvesting,forwarding and soil tillage operations are among the main causes for compaction of forest soils,with potential impacts on *** concern is especially important in areas with soils that are naturally compacted(fragipans and duripans).In these soils,tillage operations include the use of subsoilers that can reach depths of more than one meter and require heavy tractors that exert high pressure on the *** of the ways to try to minimize the effect of this compaction is by retaining harvest *** objective of this study was to evaluate the impacts of eucalyptus harvesting on soil physical attributes,as well as to determine the potential of different types of residue management to reduce compaction from the soil tillage *** experiments were conducted in the same area with a Yellow *** the first experiment,compaction caused by mechanized harvesting with harvester+forwarder was *** the second experiment,different managements of harvest residues were examined as potential modifiers of soil compaction during tillage for new *** this,three managements systems were tested:(1)retention of all harvest residues and litter from the previous rotation(HR+L),(2)retention of litter from the previous rotation(L),and(3)removal of harvest residues and litter from the previous rotation(WR).Before and after harvest,sampling was carried out in the planting rows and inter-rows,and after tillage,samples were collected in the traffic line of the subsoiler-tractor *** both experiments,undisturbed soil samples were collected from the center of the 0-10,10-20,20-40,40-60,and 60-100 cm layers to determine soil density and total *** each period and site of evaluation,mechanical resistance to penetration up to the 60-cm depth was also *** harvesting operation increased soil density at 0-10 and 60-100 cm depths only in the *** of harvest residues and litter(HR+L)after harvesting avoi

关键词： Soil penetration resistance Harvester+forwarder Soil tillage Soil density Cohesive soils

Considerations of Electricity Supply Quality in Spain

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Journal of Energy and Power Engineering 2012年第12期6卷 1976-1983页

作者： rafael Munoz SergioValero Demetrio Lopez Carolina Senabre Department of Infrastructure University of Alicante S. Vic. Raspeig Alicante c.p. 03690 Spain Department of Mechanical and Energy Engineering Area of Electrical Engineering University Miguel Hernfndez Elche c.p.03203 Spain Department of Electrical Engineering Alsanbo S.A. Company Elche 03202 Spain

The quality of supply in Spain is regulated by Act 54/1997 as the basic standard and further developed by Royal Decree 1955/2000, among others. Also this law （1997） introduces the division between generators, distribution companies and retailers. The aim of this paper is to provide an overview of the fundamental parameters to be taken into account when examining the status of national regulations in Spain on the quality of electricity supply, in addition to describing the various agents intervening in these. There are two more aspects to consider： the guarantee of supply and energy is provided at the lowest cost to consumers. The authors propose to include phase-shifting transformers at specific strategic points, in accordance with power flow control principles in parallel circuits. Finally, it can be concluded that Royal Decree 222/2008 needs reviewing and applying effectively, as do modifications to Royal Decree 1995/2000 providing remuneration that effectively induces electricity companies to invest in their networks, and ends with ＂a well-paid electricity company is obliged to invest in network improvements＂.

关键词： Power distribution power quality quality of supply.

Prediction of the Inductance in a Synchronous Linear Permanent Magnet Generator

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Journal of Electromagnetic Analysis and Applications 2011年第5期3卷 155-159页

作者： Boel Ekergard rafael Waters Mats Leijon The Division for Electricity Uppsala UniversityUppsalaSweden The Wave Energy Converter Department The Wave Energy Company Seabased Industry ABUppsalaSweden

This paper presents calculations of the varying inductances profile for a synchronous linear surface mounted permanent magnet generator in an ABC reference system. Calculations are performed by utilizing the reluctance term, known from analytic calculations and finite element method simulations. With the inductance term identified, the voltage difference between the generator’s no load and load voltage can be calculated and an external circuit can be designed for optimal use of the generator. Two different operation intervals of the linear generator are considered and the results are discussed. The result indicates that time costly finite element simulations can be replaced with simple analytical calculations for a surface mounted permanent magnet linear generator.

关键词： Wave Power Synchronous Linear Permanent Magnet Generator Varying Inductance ABC of Frame Reference

Energy Audit in the Meat Processing Industry—A Case Study in Hermosillo,Sonora Mexico

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Journal of Environmental Protection 2016年第1期7卷 14-26页

作者： Nora Munguia Luis Velazquez Tania Poom Bustamante rafael Perez Johannes Winter Markus Will Bernd Delakowitz Sustainability Graduate Program Industrial Engineering Department University of Sonora Hermosillo Mexico Work Environment Department University of Massachusetts Lowell Lowell MA USA Faculty of Mathematics and Natural Sciences University of Applied Sciences Zittau/Gorlitz Zittau Germany

The meat processing industry, due to its high energy consumption, needs to be assessed in an energy usage basis. This paper reports the results and implications of an energy audit in a meat processing industry. In addition, this work provides a comprehensive and practical approach to energy saving measures in the assessed company to recognize factors that can determine a possible transition to sustainable patterns of electricity consumption. The paper described the application to energy auditing, developed by AFNOR (2014) for efficient energy management along with ISO 50001 (energy management systems). For a more specific energy auditing the guide described by Dall “O” (2013) was used. In this case, a study of an integrative characterization of the company’s energy consumption is made. The research has been divided in two main sections: the first includes an analysis about the characterization of the energy consumption within a meat processing company in the three sustainable approaches such as economical, societal and mainly environmental implications;second, a proposal for strategic energy management measures focusing on high consumer types of facilities. The results obtained allow the identification of main processes with significant correlations in terms of energy consumption within the company. This data has the potential for energy savings. The data acquisition process prompts the development of practical and accessible energy efficiency measures. In addition, a benchmarking analysis with several tools is performed. Altogether, this work gives guidance on the implementation of energy auditing in industries within its geographical and industrial sector limitations.

关键词： Energy Efficiency Energy Audits Energy Consumption Industrial Buildings

A Review of the Production Cycle of Titanium Dioxide Pigment

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Materials Sciences and Applications 2014年第7期5卷 441-458页

作者： Manuel Jesús Gázquez Juan Pedro Bolívar rafael Garcia-Tenorio Federico Vaca Departamento de Física Aplicada Universidad de HuelvaHuelvaEspana Departamento de Química Proyecto PrometeoUniversidad Técnicas Particular de Loja(UTPL)LojaEcuador Departamento de Física Aplicada II Universidad de SevillaSevillaEspaña

Titanium is a very important element for several industrial applications, being one of the ninth most abundant elements in the Earth’s crust (0.63% wt). In this work it will discuss the different mining and industrial activities involved in the production of titanium dioxide. The first step analyzed will treat about the beneficiation mining process of titanium mineral, and secondly, it will discuss the two main processes of the TiO2 manufacturing (sulphate and chloride routes). In addition, we will show different uses of the titanium dioxide pigment as filler in paper, plastics and rubber industries and as flux in glass manufacture, etc. Finally, we will show that the old wastes are currently called co-products since they were valorized, being commercialized by the Spanish industry of TiO2 production in different fields such as agriculture, civil engineering, or cement manufacturing.

关键词： Titanium Minerals Titanium Dioxide Pigment Properties and Uses of Tio2 Valorization of Co-Products

A Parallel Approach for Real-Time Power Flow in Distribution Networks

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Journal of Energy and Power Engineering 2013年第3期7卷 589-595页

作者： rafael G. Milbradt Luciane N. Canha Pedro B. Zorrilla Alzenira R. Abaide Paulo R. Pereira Sandro R.Schmaedecke Centre of Studies in Energy and Power Systems Federal University of Santa Maria Santa Maria 97105-900 Brazil State company of Electric Power Distribution of Rio Grande do Sul Porto Alegre 91410-900 Brazil

The new reality of smart distribution systems with use of generation sources of small and medium sizes brings new challenges for the operation of these systems. The complexity and the large number of nodes requires use of methods which can reduce the processing time of algorithms such as power flow, allowing its use in real time. This paper presents a known methodology for calculating the power flow in three phases using backward/forward sweep method, and also considering other network elements such as voltage regulators, shunt capacitors and sources of dispersed generation of types PV （active power and voltage） and PQ （active and reactive power）. After that, new elements are introduced that allow the parallelization of this algorithm and an adequate distribution of work between the available processors. The algorithm was implemented using a multi-tiered architecture; the processing times were measured in many network configurations and compared with the same algorithm in the serial version.

关键词： Distribution power flow real-time power flow distribution automation dispersed generation parallel algorithm.