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实验室空气品质实测与分析
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作者 路欣豪 赵子健 +3 位作者 刘颖琪 余培滨 符蔚春 江海斌 《山东化工》 CAS 2024年第17期190-192,195,共4页
为了探究建环专业焓差法实验室、暖通空调实验室(一)、暖通空调实验室(二)、热工实验室、流体力学实验室、太阳能测试实验室等各个实验室的空气品质,在实验室做实验时,实验开始后30和50 min分别对各实验室的温度、相对湿度、风速、二氧... 为了探究建环专业焓差法实验室、暖通空调实验室(一)、暖通空调实验室(二)、热工实验室、流体力学实验室、太阳能测试实验室等各个实验室的空气品质,在实验室做实验时,实验开始后30和50 min分别对各实验室的温度、相对湿度、风速、二氧化碳浓度、噪声、甲醛、TVOC、PM_(2.5)以及PM_(10)等9个指标进行两次实测,并与相应规范进行比较和分析,提出改进建议。 展开更多
关键词 实验室 空气品质 测试
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基于视觉成像的生物安全金标试条检测仪
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作者 王慧敏 杨成文 赵友全 《光谱仪器与分析》 2009年第Z1期170-175,共6页
纳米胶体金试纸条广泛应用于生化战剂、食品药品、医学检验检疫等多个领域,具有现场检测、速度快、不受实验室条件限制等优点。本文研制了一种胶体金显色条纹识读的,基于图像识别技术的显色度分析仪,具备样品滴定、图像采集、身份识别... 纳米胶体金试纸条广泛应用于生化战剂、食品药品、医学检验检疫等多个领域,具有现场检测、速度快、不受实验室条件限制等优点。本文研制了一种胶体金显色条纹识读的,基于图像识别技术的显色度分析仪,具备样品滴定、图像采集、身份识别和定量分析等功能。实验验证了本文研制工作可望替代现有的光电扫描式阅读器。 展开更多
关键词 图像识别技术 胶体金试纸条 图像采集 胶体金检测 色条 检测仪器 试条 医学检验 生物安全 实验室环
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解决食品化学检验准确性偏差问题的对策 被引量:1
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作者 王娴婷 《化工管理》 2018年第24期195-196,共2页
在中国食品的发展进程中,有诸多因素会影响到其发展,食品化学检验的科学性则是一个关键的影响因素。所以,在食品化学检验工作的推进中,食品化学测验的科学程度还要不断地提升。文章首先对食品化学检验准确性产生影响的基本因素进行了分... 在中国食品的发展进程中,有诸多因素会影响到其发展,食品化学检验的科学性则是一个关键的影响因素。所以,在食品化学检验工作的推进中,食品化学测验的科学程度还要不断地提升。文章首先对食品化学检验准确性产生影响的基本因素进行了分析,然后对提高食品化学检验准确性的策略进行了讨论,提升了检验人才的水平,确保了我国的食品化学检验迈向可持续发展的道路。 展开更多
关键词 食品化学检验 实验室环 综合培训
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Dynamic surface control-backstepping based impedance control for 5-DOF flexible joint robots 被引量:5
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作者 熊根良 谢宗武 +3 位作者 黄剑斌 刘宏 蒋再男 孙奎 《Journal of Central South University》 SCIE EI CAS 2010年第4期807-815,共9页
A new impedance controller based on the dynamic surface control-backstepping technique to actualize the anticipant dynamic relationship between the motion of end-effector and the external torques was presented. Compar... A new impedance controller based on the dynamic surface control-backstepping technique to actualize the anticipant dynamic relationship between the motion of end-effector and the external torques was presented. Comparing with the traditional backstepping method that has "explosion of terms" problem, the new proposed control system is a combination of the dynamic surface control technique and the backstepping. The dynamic surface control (DSC) technique can resolve the "explosion of terms" problem that is caused by differential coefficient calculation in the model, and the problem can bring a complexity that will cause the backstepping method hardly to be applied to the practical application, especially to the multi-joint robot. Finally, the validity of the method was proved in the laboratory environment that was set up on the 5-DOF (degree of freedom) flexible joint robot. Tracking errors of DSC-backstepping impedance control that were 2.0 and 1.5 mm are better than those of backstepping impedance control which were 3.5 and 2.5 mm in directions X, Y in free space, respectively. And the anticipant Cartesian impedance behavior and compliant behavior were nchieved successfully as depicted theoretically. 展开更多
关键词 Cartesian impedance control dynamic surface control BACKSTEPPING PPSeCo flexible joint robots
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An Open Architecture for Converged Internet of Things 被引量:3
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作者 邹俊伟 吴岳辛 张晓莹 《China Communications》 SCIE CSCD 2011年第1期151-155,共5页
An open architecture for converged Internet of Things (IoT) is proposed in this paper.By using this model,the various and huge amount of data can be converted into converged data and then encapsulated as service packa... An open architecture for converged Internet of Things (IoT) is proposed in this paper.By using this model,the various and huge amount of data can be converted into converged data and then encapsulated as service packages.Moreover,a Representational State Transfer (REST) platform has been implemented in the lab environment.The merit of this architecture is the enhancement of data efficiency.Experimental results are provided to show the benefits of the proposed architecture. 展开更多
关键词 Internet of Things Representational State Transfer (REST) converged data
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A study on coupling technique and implementation of the wave-circulation coupled model 被引量:1
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作者 张志远 Liu Li +5 位作者 Zhou Yufeng Zhang Cheng Li Ruizhe Chen Yushu Song Guojie Yang Guangwen 《High Technology Letters》 EI CAS 2014年第1期82-87,共6页
The coupler is fundamental for a coupled model to realize complex interactions among component models.This paper focuses on the coupling process of Wave-Circulation(W-C) coupled model which consists of MASNUM(key labo... The coupler is fundamental for a coupled model to realize complex interactions among component models.This paper focuses on the coupling process of Wave-Circulation(W-C) coupled model which consists of MASNUM(key laboratory of marine science and numerical modeling wave model)and POM(Princeton Ocean Model).The current coupling module of this coupled model is based on the inefficient I/O file,which has already become a performance bottleneck especially when the coupled model utilizes a large number of processes.To improve the performance of the W-C model,a flexible coupling module based on the model coupling toolkit(MCT) is designed and implemented to replace the current I/O file coupling module in the coupled model.Empirical studies that we have carried out demonstrate that our online coupling module can dramatically improve the parallel performance of the coupled model.The online coupling module outperforms the I/O file coupling module.When processes increase to 96,the whole process of EXP-C takes only 695.8 seconds,which is only 58.8%of the execution time of EXP-F.Based on our experiments under 2D Parallel Decomposition(2DPD),we suggest setting parallel decomposition strategies automatically to component models in order to achieve high parallel efficiency. 展开更多
关键词 coupling technique model coupling toolkit (MCT) W-C coupled online cou-pling module 2D Parallel Decomposition (2DPD) parallel performance
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Determining the degree of saturation of rocks as a function of time:A case study from mountainous area of Turkey
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作者 Serhat DAG 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2307-2319,共13页
The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) sta... The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) standard in rocks is sufficient or not, and to examine how the degree of saturation of rocks may be determined as a function of time. For this purpose, samples from five different rock groups including igneous(andesite, granite, andesitic tuff) and sedimentary(limestone, sandstone) exposed in Gümü?hane city which is from mountainous area of north-eastern Turkey, have been compiled. Measurements were taken on the samples left for saturation under laboratory conditions as a result of which the degree of saturation values at the end of these time periods were determined. Similarly, at the end of 48 hours, the samples were left to dry under atmospheric conditions in the laboratory environment and their time dependent degree of saturation were also calculated at different times. The changes as a function of time in the degree of saturation were then examined mathematically using non-linear, exponential and logarithmic functions. Graphs and equations related with the acquired time-degree of saturation values and the correlation coefficient(r) values for these equalities have indicated a high accordance between time and degree of saturation for the studied rock groups. The applied methodology will be beneficial for determining the degree of saturation based on time for engineering studies that will be carried out in similar lithologies. 展开更多
关键词 Degree of saturation POROSITY TIME Correlation coefficient
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An Alternative Approach for the Determination of Soil Water Mobility
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作者 M.P.C.ENGLER R.CICHOTA +3 位作者 Q.DE JONG VAN LIER E.M.BLOEM G.SPAROVEK E.SCHNUG 《Pedosphere》 SCIE CAS CSCD 2008年第3期328-334,共7页
A new laboratory method was proposed to establish an easily performed standard for the determination of mobile soil water close to real conditions during the infiltration and redistribution of water in a soil. It cons... A new laboratory method was proposed to establish an easily performed standard for the determination of mobile soil water close to real conditions during the infiltration and redistribution of water in a soil. It consisted of applying a water volume with a tracer ion on top of an undisturbed ring sample on a pressure plate under a known suction or pressure head. Afterwards, soil water mobility was determined by analyzing the tracer-ion concentration in the soil sample. Soil water mobility showed to be a function of the applied water volume. No relation between soil water mobility and applied pressure head could be established with data from the present cxperiment. A simple one- or two-parameter equation can be fitted to the experimental data to parameterize soil water mobility as a function of applied solute volume. Sandy soils showed higher mobility than loamy" soils at low values of applied solute volumes, and both sandy and loamy soils showed an almost complete mobility at high applied solute volumes. 展开更多
关键词 laboratory method mobile-immobile water pressure head soil texture
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Net-Zero Energy Building Enhancement for a Leadership in Energy and Environmental Design Platinum Educational Facility
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作者 Aydin Tabrizi Paola Sanguinetti 《Journal of Civil Engineering and Architecture》 2014年第8期963-972,共10页
In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university... In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university is 42 years with an EUI (energy use intensity) of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED (leadership in energy and environmental design) system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum's energy performance strategies include a double-skin facade to reduce energy consumption and PV (photovoltaic) panels to generate onsite energy. This study considers various scenarios to meet NZEB (net-zero energy building) criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for: (a) seasonal comparison; (b) facility occupancy; (c) PV panels' addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol (return on investment) and PV panel's efficiency for this specific educational building. 展开更多
关键词 NZEB double skin facade energy plus educational building PV panels LEED
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Ringlike failure experiment of thick-walled limestone cylinder specimens in triaxial unloading tests 被引量:2
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作者 Zhang Houquan He Yongnian Liu Honggang Han Lijun Shao Peng 《Mining Science and Technology》 EI CAS 2011年第3期445-450,共6页
In order to study the failure of surrounding rock under high in situ stress in deep underground engineering projects, disturbed by excavation unloading, we carried out triaxial unloading experiments using thickwalled ... In order to study the failure of surrounding rock under high in situ stress in deep underground engineering projects, disturbed by excavation unloading, we carried out triaxial unloading experiments using thickwalled cylinder specimens on a TATW-2000 rock servo-controlled triaxial testing machine in a laboratory. The specimens were made of limestone material, taken from Tongshan county, Xuzhou city, Jiangsu province, China. In our experiments, rock deformation and failure behavior was studied through loading and unloading of inner hole pressure of thick-walled cylinder specimens. At first, the axial stress, confining pressure and inner pressure were increased simultaneously to a specified designed state of stress. Then, keeping the axial stress and confining pressure stable, the pressure on the inner hole was decreased until the specimen was fractured. When the inner pressure was released completely but the specimen did not fracture, the confining pressure was decreased subsequently until complete failure occurred. Our experimental results suggest that traces of major circular ringlike fractures with a number of radial cracks often appear in thick cylinder walls. This type of ringlike failure phenomenon, similar to intermittent zonal fracturing characteristics of deep exploitation, has, so far, not been published. Our experimental results show that rock deformation and failure behavior of thick-walled limestone cylinders vary under different stress paths between loading and unloading. Tensile failure and orderly failure surfaces occur under unloading conditions while irregular damaged rock blocks are produced during loading failure. This type of triaxial unloading experiment provides for new research methodology and approach for thorough investigations on intermittent zonal fracturing in deep underground excavations. 展开更多
关键词 Thick-walled cylinder specimens Triaxial tests Unloading Ringlike failure
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Effects of temperature,algae biomass and ambient nutrient on the absorption of dissolved nitrogen and phosphate by Rhodophyte Gracilaria asiatica 被引量:2
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作者 杜荣斌 刘立明 +1 位作者 王爱敏 王勇强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期353-365,共13页
Gracilaria asiatica, being highly efficient in nutrient absorption, is cultivated in sea cucumber ponds to remove nutrients such as nitrogen and phosphate. It was cultured in a laboratory simulating field conditions, ... Gracilaria asiatica, being highly efficient in nutrient absorption, is cultivated in sea cucumber ponds to remove nutrients such as nitrogen and phosphate. It was cultured in a laboratory simulating field conditions, and its nutrient absorption was measured to evaluate effects of environmental conditions. Ammonia nitrogen (AN), nitrate nitrogen (NN), total inorganic nitrogen (TIN), and soluble reactive phosphorus (SRP) uptake rate and removal efficiency were determined in a 4~2 factorial design experiment in water temperatures (T) at 15~C and 25~C, algae biomass (AB) at 0.5 g/L and 1.0 g/L, total inorganic nitrogen (TIN) at 30 ~tmol/L and 60 ~tmol/L, and soluble reactive phosphorus (SRP) at 3 and 6 ~tmol/L. AB and ambient TIN or SRP levels significantly affected uptake rate and removal efficiency of AN, NN, TIN, and SRP (P〈0.001). G. asiatica in AB of 0.5 g/L showed higher uptake rate and lower removal efficiency relative to that with AB of 1.0 g/L. Nitrogen and phosphorus uptake rate rose with increasing ambient nutrient concentrations; nutrient removal efficiency decreased at higher environmental nutrient concentrations. The algae preferred to absorb AN to NN. Uptake rates of AN, NN, and SRP were significantly affected by temperature (P〈0.001); uptake rate was higher for the 25~C group than for the 15~C group at the initial experiment stage. Only the removal efficiency of AN and SRP showed a significant difference between the two temperature groups (P〈0.01). The four factors had significant interactive effects on absorption of N and P, implying that G. asiatica has great bioremedial potential in sea cucumber culture ponds. 展开更多
关键词 ALGAE Gracilaria asiatica Chang et Xia nutrient removal NITROGEN soluble reactive phosphate
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Industrial Fault Signals Propagation and Current Signature Analysis
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作者 Alireza Gheitasi Adnan AI-Anbuky 《Journal of Energy and Power Engineering》 2013年第2期361-369,共9页
Motor current signature analysis provides good results in laboratory environment. In real life situation, electrical machines usually share voltage and current from common terminals and would easily influence each oth... Motor current signature analysis provides good results in laboratory environment. In real life situation, electrical machines usually share voltage and current from common terminals and would easily influence each other. This will result in considerable amount of interferences among motors and doubt in identity of fault signals. Therefore, estimating the mutual influence of motors will help identifying the original signal from the environmental noise. This research aims at modelling the propagation of signals that are caused by faults of induction motors in power networks. Estimating the propagation pattern of fault signal leads to a method to discriminate and identify the original source of major events in industrial networks. Simulation results show that source of fault could be identified using this approach with a higher certainty than anticipated output coming of any individual diagnosis. 展开更多
关键词 Motor current signature analysis signal interference decision making signal propagation.
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Nutrient-controlled growth of Skeletonema costatum : an applied model
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作者 孙科 丘仲锋 +1 位作者 何宜军 尹宝树 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期608-625,共18页
To model Skeletonema costatum blooms and their relationship with environmental parameters in situ, a S. costatum-specific zero-dimensional box model based on the mechanistic model Eco3M was established using physiolog... To model Skeletonema costatum blooms and their relationship with environmental parameters in situ, a S. costatum-specific zero-dimensional box model based on the mechanistic model Eco3M was established using physiological features. The parameters were calibrated using experimental counterparts, and simulations were compared with published laboratory findings. The resulting normalized objective function (NOF) values are less than 1.0 (and in most cases less than 0.58) and the values for the slope y (between 0.656 7-1.127 4) and R2 (between 0.806 8-0.971) are close to 1.0 for most of the sub-figures. This indicates good agreement between simulated and measured data and suggests that the model reproduces the general characteristics of S. costatum growth and use of nutrients under different N- or P-limiting conditions. The model is appropriate for further applications and can be used to test more scenarios using other nutrients. 展开更多
关键词 Skeletonema costatum red tide algal bloom MODELING GROWTH China Sea
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Conversion of Fuel-N to N2O and NOx during Coal Combustion in Combustors of Different Scale 被引量:3
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作者 周昊 黄燕 +2 位作者 莫桂源 廖子昱 岑可法 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期999-1006,共8页
With focus on investigating the effect of combustor scale on the conversion of fuel-N to NOx and N20, experiments are carried out in three combustors, including single coal particle combustion test rig, laboratory sca... With focus on investigating the effect of combustor scale on the conversion of fuel-N to NOx and N20, experiments are carried out in three combustors, including single coal particle combustion test rig, laboratory scale circulating fluidized-bed boiler (CFB) and full scale CFB in this work. For single coal particle combustion, the majority of f-uel-N (65%-82%) is released as NOx, while only a little (less than 8%) fuel-N yields N20. But in labora- tory scale CFB, the conversion of fuel-N to N20 is increases, but the conversion of fuel-N to NOx is quite less than that of single coal particle combustion. This is because much char in CFB can promote the NOx reduction by in- creasing N20 formation. In full scale CFB, both of the conversion of fuel-N to NOx and the conversion of fuel-N to N20 are smaller than laboratory scale CFB. 展开更多
关键词 fuel-N N2O NOx COAL fluidized bed
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Effect of galvanic contact on the flotability of galena in the presence and absence of a collector 被引量:2
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作者 M.B.Eslami Andargoli S.Jannesar Malakooti +1 位作者 F.Doulati Ardejani H.Abdollahi 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期629-632,共4页
In this paper,the effect of various electrochemical environments in the galena flotation is investigated.The electrochemical environments consisted of a ball mill for grinding of galena ore and a Denver flotation cell... In this paper,the effect of various electrochemical environments in the galena flotation is investigated.The electrochemical environments consisted of a ball mill for grinding of galena ore and a Denver flotation cell for flotation of galena in the laboratory scale.In order to achieve the maximum recovery with sodium hyposulfite,the concentrations of 0.06 and 0.12 M of air and nitrogen gases have been used to control the pulp potential in the Denver flotation cell.The galena sample was from the ''Era mine'' which is located in the Kiyasar area,north of Iran.This mine contains:Galena(PbS) at least 22%,Fluorite(CaF 2) 73.37%,Quartz(SiO 2) 2.54% and other minerals such as Cerussite(PbCO 3) and Kaolinite(Al 2 Si 2 O 5(OH) 4).Flotation of Galena was conducted in a 0.12 M of sodium hyposulfite solution.It was found that the amount of recovery by this process was 85% and 63% in the presence and absence of potassium amyl xanthate(KAX) and at an estimated potential of 280 to 350 mV respectively while the recovery was 70% and 52% at an approximate potential of 175 to 210 mV in water in the presence and absence of collector(KAX). 展开更多
关键词 Flotation Collector Galena Electrochemical Galvanic interactions
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Effect of temperature and photoperiod on maturation of Cephalothrix hongkongiensis(Nemertea: Palaeonemertea)
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作者 李应东 宋肖跃 +2 位作者 张珊珊 朱林 孙世春 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期764-772,共9页
The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few sp... The limited knowledge about the relationships between environmental factors and the maturation and reproductive seasonality of nemerteans is mostly obtained from field studies, and in many cases is conjectural. Few species have been studied under well-controlled laboratory conditions. In this work, the effects of temperature and photoperiod on gonad development and spawning of Cephalothrix hongkongiensis were observed by rearing worms under different temperatures and photoperiods. Worms reared at 4~C and 6~C showed no growth or gonadal development, and all died within 109 days. At 8~C and 12~C, gonads could be seen from 90 days to the termination of the 360-day experiment, but no spawning was observed. Worms maintained at 16, 24, and 28~C showed both gonadal development and spawning, and matured faster at higher temperatures. Under a fixed temperature (16℃), photoperiod did not have any significant impact on maturation and spawning. It is likely that temperature plays a major role in regulating the maturation and reproductive cycle of C. hongkongiensis. 展开更多
关键词 TEMPERATURE PHOTOPERIOD gonad development REPRODUCTION Cephalothrix hongkongiensis NEMERTEA
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An Environmental Wind Tunnel Laboratory of SP
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作者 姚增权 《Electricity》 2002年第2期38-42,共5页
This paper briefs the background and process of setting-up andupdating of Environmental Wind Tunnel Laboratory of State Power Corporation,details the environmental wind tunnel, completed measuring instruments andequip... This paper briefs the background and process of setting-up andupdating of Environmental Wind Tunnel Laboratory of State Power Corporation,details the environmental wind tunnel, completed measuring instruments andequipment of the laboratory, and also describes the experimental projects thePower Environmental Protection Research Institute has completed, theexperiences gained and the services the Institute can provide in the future.[ 展开更多
关键词 environmental wind tunnel LABORATORY physical simulation
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The International Research Group in Geophysics Europe Africa: A Laboratory without Borders in the Earth Science and Environment
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作者 Christine Amory-Mazaudier 《Journal of Life Sciences》 2012年第3期335-341,共7页
It was in 1995 that, at the end of the international project IEEY (International Equatorial Electrojet Year), African and European scientists decided to create the IRGGEA (International Group in Geophysics Europe A... It was in 1995 that, at the end of the international project IEEY (International Equatorial Electrojet Year), African and European scientists decided to create the IRGGEA (International Group in Geophysics Europe Africa) in order to pursue the scientific work started during the IEEY project, The main objective of IRGGEA was to introduce new fields of research in Africa and built teams of African scientists recognized at an international level in these new fields. To reach this goal, we developed days after days methods to manage smoothly a large network of scientists from developed and developing countries. After a short introduction on the field of research developed in the IRGGEA, we present the organization of the work based on sharing practices and the results obtained in terms of scientific publications and socio-cultural aspects as the increase of the number of women and positions for students in their countries. Such an experience is easy to reproduce. 展开更多
关键词 Scientific network ethical rules GEOPHYSICS sustainable research Africa.
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Solving the Perennial Problems of Inadequate Physical Laboratories in Africa Through the Use of Virtual Reality Technology and Tools
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作者 Moses Okechukwu Onyesolu 《Computer Technology and Application》 2011年第1期67-74,共8页
The major restriction for learning in science and engineering education in Africa is the absence of equipped laboratories. Where laboratory is available, there is the problem of obsolete and antiquated materials, whic... The major restriction for learning in science and engineering education in Africa is the absence of equipped laboratories. Where laboratory is available, there is the problem of obsolete and antiquated materials, which are seldom available for use. In most Universities in Africa, there is inadequate supply of laboratory space and laboratory materials. The laboratories only have the items of equipment that were provided when the universities were established, this has hampered learning. An alternative educational approach is required to address the aforementioned problems and provide a cost-effective solution for education as well as a valuable complementary or learning tool for university students. The alternative approach is the use of Virtual Reality (VR) technology to simulate virtual learning environments such as virtual reality laboratories. This is a one solution to inadequate physical laboratories in Africa. 展开更多
关键词 Virtual reality (VR) simulation laboratory second-life.
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Arctic Oscillation Responses to Black Carbon Aerosols Emitted from Major Regions
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作者 WAN Jiang-Hua LI Shuanglin 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第4期226-232,共7页
The responses of the Arctic Oscillation(AO) to global black carbon(BC) and BC emitted from major regions were compared using the atmospheric general circulation model Geophysical Fluid Dynamics Laboratory(GFDL) atmosp... The responses of the Arctic Oscillation(AO) to global black carbon(BC) and BC emitted from major regions were compared using the atmospheric general circulation model Geophysical Fluid Dynamics Laboratory(GFDL) atmospheric general circulation model(AGCM) Atmospheric Model version 2.1(AM2.1). The results indicated that global BC could induce positive-phase AO responses, characterized by negative responses over the polar cap on 500 h Pa height fields, and zonal mean sea level pressure(SLP) decreasing while zonal wind increasing at 60°, with the opposite responses over midlatitudes. The AO indices distribution also shifted towards positive values. East Asian BC had similar impacts to that of global BC, while the responses to European BC were of opposite sign. South Asian BC and North American BC did not affect the AO significantly. Based on a simple linear assumption, we roughly estimated that the global BC emission increase could explain approximately 5% of the observed positive AO trend of +0.32 per decade during 1960 to 2000. 展开更多
关键词 black carbon Arctic Oscillation linear trend
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