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Effects of geometric design of forest road and roadside vegetation on traffic noise reduction

Journal of Forestry Research 2016年第2期27卷 463-468页

作者： Seyed Ata Ollah Hosseini Seyran Zandi Asghar Fallah Mehran Nasiri Department of Forestry and Forest Economics Faculty of Natural Resources University of Tehran Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources alborz road development and construction corporation Civil Engineers office

Geometric design of forest roads and design of their landscapes can reduce noise pollution and its harmful effects on human health. We investigated the effects of technical and biological parameters such as geometric road design and various roadside tree stands on reducing noise pollution according to the tree density and distance from roadway in Darabkola Forests, Sari, Iran. We recorded the noise generated by a car （Land Rover） relative to changes in longitudinal slope, horizontal curve radius and type of road pavement. We also measured noise levels according to roadside tree density and stand type （coniferous and hardwood） in 40 rectangular plots of three widths （25, 100 and 300 m） and 50 m length that were randomly demar- cated along forest roads. The changes in noise level were recorded using a decibel meter with an accuracy of q-1.5 dB and resolution of 0.1 dB. Noise levels were higher alongside unpaved roads than alongside paved roads. There was an inverse relationship between the measured noise level and horizontal curve radius. The rate of noise level on horizontal curve with a radius less than 30, 30-45 m and more than 45 m were 64.8, 70.8 and 75.9 dB, respectively. The noise level increased with the increasing longitudinal slope of the road. There was a significant difference between the noise level on slopes less than 3 % （67 dB） and 3-8 % （71.2 dB） in comparison with slopes greater than 8 % （77.8 dB）, （p 〈 0.05）. Pinus brutia L. reduced the noise level more （about 6 dB） in stands of 1/3 density of mixed hardwoods within 25 m from middle of the road. Careful design of geometric properties of forest roads as well as planting coniferous trees with hardwoods is a suitable solution for reducing noise pollution.

关键词： Forest road Noise pollution Noise level Vegetation Distribution

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Ripple-effect analysis for operational architecture of air defense systems with supernetwork modeling

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Journal of Systems Engineering and Electronics 2014年第2期25卷 249-264页

作者： Zhigang Zou Fuxian Liu Shiman Sun Lu Xia Chengli Fan School of Air and Missile Defense Air Force Engineering University Research & development Center China Airport Construction Group Corporation

In order to solve the problem that the ripple-effect analy- sis for the operational architecture of air defense systems （OAADS） is hardly described in quantity with previous modeling approaches, a supernetwork modeling approach for the OAADS is put for- ward by extending granular computing. Based on that operational units and links are equal to different information granularities, the supernetwork framework of the OAADS is constructed as a “four- network within two-layer” structure by forming dynamic operating coalitions, and measuring indexes of the ripple-effect analysis for the OAADS are given combining with Laplace spectral radius. In this framework, via analyzing multidimensional attributes which inherit relations between operational units in different granular scales, an extended granular computing is put forward integrating with a topological structure. Then the operation process within the supernetwork framework, including transformation relations be- tween two layers in the vertical view and mapping relations among functional networks in the horizontal view, is studied in quantity. As the application case shows, comparing with previous modeling approaches, the supernetwork model can validate and analyze the operation mechanism in the air defense architecture, and the ripple-effect analysis can be used to confirm the key operational unit with micro and macro viewpoints.

关键词： operational architecture air defense system super-network model Laplace spectral radius ripple-effect analysis.

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Thermal design for the high-power LED lamp

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Journal of Semiconductors 2011年第1期32卷 61-64页

作者：田晓改陈伟张继勇 NVC Lighting Technology corporation Research & development Center(Shanghai)

This paper summarizes different kinds of heat sinks on the market for high power LED lamps. Analysis is made on the thermal model of LED, PCB and heat sink separately with a simplified mode provided. Two examples of s... 详细信息

关键词： high power LED LED lamp lamp body (heat sink) thermal simulation

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Microstructures of brazing zone between titanium alloy and stainless steel using various filler metals

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中国有色金属学会会刊：英文版 2012年第S3期22卷 639-644页

作者： Taeshin CHUNG Jungsoo KIM Jeongseok BANG Byoungho RHEE Daegeun NAM Agency for Defense development Korea Institute of Industrial Technology Vitzotech corporation

Titanium alloy (Ti-Al-V alloy) substrate was brazed with stainless steel (STS304) using filler *** an optimized brazing condition,various filler metals were *** were observed at each *** metals were titanium based 40Ti-20Zr-20Cu-20Ni,silver based Ag 5Pd,and nickel based Ni-7Cr-3.1B-4.5Si-3Fe-0.06C (BNi2) and Ni-14Cr-10P-0.06C (BNi7).To select a good filler metal for brazing process,wetting test was performed at 880-1050 °*** was not brazed using silver based filler metals,but at the conditions using titanium and nickel based filler metals had brazed zone between titanium alloy and stainless ***,titanium alloy was eroded during brazing using titanium based filler *** based filler metal has a good brazed zone between titanium alloy and stainless steel among the filler metals.

关键词： brazing filler metal titanium alloy stainless steel

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Welding of SA213-T91 and SA213-T23 heat-resistant steels applied in ultra supercritical thermal power units

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China Welding 2011年第3期20卷 52-56页

作者：郑楷徐德生邵华周立霞马杰 College of construction Engineering Jilin University Changehun 130022 School of Materials Science and Engineering Jilin University Changchun 130025 Zhuhai Power Plant Zhuhai 519050 China Xinxing construction and development corporation Beijing100039

The marteasite SA213-191 and bainite SA213-T23 high-temperature resistant steels were applied to the heating surface of the ultra supercritical thermal power unit boiler. The weld metal microstructures and welded joint performance between the two kinds of dissimilar steels were analyzed. The main reasons of the welding defects such as hot crack, cold crack, brittleness and decrease in toughness were discussed during the welding of the dissimilar heat-resistant steels of SA213- 191 and SA213-T23 in boiler manufacturing and processing operation. The welding materials were chosen and welding procedure was made according to the base metals.

关键词： martensite SA213-T91 steel bainite SA213-T23 steel weldability welding procedure

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Exploration of Complicated Oil and Gas Fields

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 65-77页

作者： Zhang Xiangning China National Oil & Gas Exploration & development corporation, Beijing Liu Linqun China National Oil & Gas Exploration & development corporation Beijing

Complicated oil and gas fields occupy an important position in oil and gas exploration. In this paper, complicated oil and gas fields are grouped into four types: fault-block, lithologic, stratigraphic and fissure types. On the basis of the new theory of petroleum geological exploration in composite oil and gas accumulation areas within continental basins, a new exploration sequence suitable for complicated oil and gas fields has been established, which comprises four stages:(1) initial exploration;(2) preliminary exploration;(3) early step-by-step exploration and development: and(4) late step-by-step exploration and development. The idea of cybernetics has been taken to control various links of a systematic exploration project so as to fully, effectively and comprehensively utilize the new exploration techniques, eventually realizing the optimization of exploration with the aim of raising the efficiency of exploration of complicated oil and gas fields.

关键词： Pro test Exploration of Complicated Oil and Gas Fields

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Study on Rotational Frequency Noise in a Centrifugal Compressor for Automobile Turbochargers

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Journal of Thermal Science 2014年第1期23卷 53-59页

作者： Daichi Wakaki Yuta Sakuka Nobuhiko Yamasaki Akihiro Yamagata Department of Aeronautics and Astronautics Kyushu University Products development Center IHI Corporation

The rotational frequency noise(also known as the pulsation noise) due to the mistuning of impeller blade rows introduced at the manufacturing stage of the impellers is observed in the small-sized centrifugal compressor for automobile turbochargers. The present paper addresses the elucidation of the generating mechanism and parameter dependency such as the kind and degree of mistuning. In order to analyze numerically the rotational frequency noise due to mistuning, the unsteady computational fluid dynamics(CFD) of the whole compressor including volute is executed, and the resultant time history of the pressure is fed into the spectral analysis.

关键词： Centrifugal compressor Impeller Diffuser Volute Pulsation noise Mistuning

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A nanofilter composed of carbon nanotube-silver composites for virus removal and antibacterial activity improvement

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Journal of Environmental Sciences 2016年第4期28卷 275-283页

作者： Jun Pyo Kim Jae Ha Kim Jieun Kim Soo No Lee Han-Oh Park Nano development Team Bioneer Corporation Daejeon 306-220 Republic of Korea

We have developed a new nanofilter using a carbon nanotube-silver composite material that is capable of efficiently removing waterborne viruses and *** nanofilter was subjected to plasma surface treatment to enhance its flow rate,which was improved by approximately 62%.Nanoscale pores were obtained by fabricating a carbon nanotube network and using nanoparticle fixation technology for the removal of *** pore size of the nanofilter was approximately 38 nm and the measured flow rate ranged from 21.0 to 97.2 L/（min·m^2）under a pressure of 1–6 kgf/cm^2 when the amount of loaded carbon nanotube-silver composite was 1.0 mg/cm^*** nanofilter was tested against Polio-,Noro-,and Coxsackie viruses using a sensitive real-time polymerase chain reaction assay to detect the presence of viral particles within the *** trace of viruses was found to flow through the nanofilter with carbon nanotube-silver composite loaded above 0.8 mg/cm^***,the surface of the filter has antibacterial properties to prevent bacterial clogging due to the presence of 20-nm silver nanoparticles,which were synthesized on the carbon nanotube surface.

关键词： Carbon nanotube Silver nanoparticle Virus removal Nanofilter Water purification

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THEORETICAL AND EXPERIMENTAL STUDIES OF STRESS DISTRIBUTION IN WEDGE-SHAPED GRANULAR HEAPS

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Acta Mechanica Solida Sinica 2014年第1期27卷 28-40页

作者： Thirapong Pipatpongsa Tadaki Matsushita Maho Tanaka Shinichi Kanazawa Katsuyuki Kawai Global Scientific Information and Computing Center Tokyo Institute of Technology Department of International development Engineering Tokyo Institute of Technology Maeda corporation Nishimatsu construction Co. Ltd Research Center for Urban Safety and Security Kobe University

The present work explains the statics of self-weight transmission restricted to a long prismatic heap inclined at an angle of repose and symmetrically formed on a rigid base. The closure of polarized principal axes with the mobilized state of stress along the slope surface is employed by imposing the orientation of principal stresses on the equilibrium equations. Comparisons were made with calculations based on the finite element method using an elastic model. Moreover, experiments on sand heaps deposited on a rectangular rigid base were conducted to validate the theoretical study. The measured pressure profile generally agreed well with theoretical results.

关键词： granular materials sand continuum medium analytical method finite element method experimental techniques

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Autothermal reforming of biogas over a monolithic catalyst

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Journal of Natural Gas Chemistry 2010年第5期19卷 477-481页

作者： Sadao Araki Naoe Hino Takuma Mori Susumu Hikazudani Hitachi Zosen corporation Business & Product Development HeadquartersTechnical Research Institute

This study focused on measurement of the autothermal reforming of biogas over a Ni based monolithic catalyst. The effects of the steam/CH4 （S/C） ratio, O2/CH4 （O2/C） ratio and temperature were investigated. The CH4 conversions were higher under all examined temperatures than the equilibrium conversion calculated using the blank outlet temperature, because the catalyst layer was heated by the exothermic catalytic partial oxidation reaction. The CH 4conversion increased with increasing O2/C ratio. Moreover, the CH4 conversion was higher than the equilibrium conversion calculated using the blank outlet temperature for O2/C〉0.42 and reached about 100% at O2/C=0.55. However, the hydrogen concentration decreased for O2/C〉0.45 because hydrogen was combusted to steam in the presence of excess oxygen. On the other hand, the hydrogen and CO2 concentrations increased and the CO concentration decreased with increasing SIC ratio. As a result, it was found that the highest hydrogen concentrations and CH4 conversions were attained at the O2/C ratios of 0.45-0.55 and the SIC ratios of 1.5-2.5. Moreover, the H2/CO ratio could also be controlled in the range from about 2 to 3.5 to give at least 90% CH4 conversion, by regulating the O2/C or S/C ratios.

关键词： autothermal reforming biogas hydrogen production monolithic catalyst Ni based catalyst

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