基于环境修正的中国农业全要素生产率度量

环境的外部性使包含环境影响的生产率度量一直是个难题,而此类研究对推动我国农业可持续发展具有重要意义。本文提出了一种度量和评估包含环境影响的农业生产率方法,在本研究中,环境的外部性通过定义一个包含市场产出和污染产出的总产出而纳入分析框架,用总产出代替传统TFP计算中的产出,包含环境影响的全要素生产率公式得以建立。利用基于单元的综合调查评价法计算了1990-2008年我国主要农业污染物排放数量,并在此基础上度量了基于环境修正的我国农业全要素生产率。研究表明在1990-2008年间我国经环境调整后的农业生产率增长呈现减小趋势,农业环境污染使农业生产率增长降低0.09%-0.6%,且呈现较大的时期变化;依据不同环境污染价值损失评估法,环境对农业全要素生产率的修正会带来或高或低的结果。为了更准确地度量环境对农业全要素生产率的影响,需要进一步探索环境污染价值评估方法,完善我国农业环境监测体系。

侦察吊舱电磁环境复杂度定量研究及软件仿真

侦察吊舱电磁环境复杂度定量度量是构建逼真的战场环境的重要步骤,为解决侦察吊舱电磁环境复杂度难以定量度量问题,分析研究了侦察吊舱所处的电磁环境,从引起电磁环境复杂度的主要影响因素出发,结合环境复杂度因素的客观性及主观性,基于灰色层次分析法及组合理论得到环境因素复杂度计算方法,给出了一个解决定量度量电磁环境复杂度的算法。在此算法基础上提出了复杂度等价替换原理,进一步简便算法的计算难度。最终,通过典型的雷达电磁环境对算法进行验证,并通过LabWindows CVI将算法软件化,实验结果表明算法对于度量复杂电磁环境的复杂度具有一定的实用意义。

外贸隐含碳对环境影响的国际比较——基于五国(地区)面板数据的实证研究

伴随着国际货物贸易,CO2的排放也在进口国与出口国之间发生转移,从而对两国环境带来影响。根据中国、美国、欧盟、日本与韩国等国(地区)面板数据对这一碳转移现象及其环境影响进行了实证研究,对五大经济体在国际贸易中的碳交换特征进行了分析比较。结果表明,这五大经济体外贸隐含碳对他国环境的贡献均为反向,即其对外贸易没有对本国环境产生拖累,而是增加了其他国家的环境负担。因此,我们认为减少碳排放需要世界各国进行协调一致的努力,并走低碳绿色发展之路。

金沙江流域(云南段)人居自然环境质量时空分异研究

基于2010、2015、2020年3期遥感影像和其他多源数据,从自然环境的角度,选取地貌、土壤、植被覆盖等10个环境质量因子作为人居自然环境质量评估指标,将熵权法、欧式距离函数等多方法复合建立流域人居自然环境质量的综合度量模型,通过GIS趋势面、Moran's I指数及冷热点分析揭示流域人居自然环境质量的时空分异规律。结果表明:流域人居自然环境质量受坡度、地貌和植被覆盖度的影响较大,环境质量优异地区的空间分布与坡度平缓、地貌适宜且植被良好的区域具有较高的重叠性;流域三期人居自然环境质量的时空演变规律表现为:空间维上,南部>北部、中部>东部>西部,从南到北,环境质量下降,中下游优于上游;时间维上,呈现出先下降后回升的趋势,尤其是中游以南的滇中地区表现尤为明显;流域整体呈正相关集聚分布,置信度高的热点区以中下游以南的楚雄州及昆明地区为主;而置信度高的冷点区覆盖整个迪庆藏族自治州。研究得出的人居自然环境度量模型及空间异质性分析方法为开展类似研究提供参考,揭示的人居自然环境时空变异规律为区域进行灾害搬迁选址和环境保护治理提供科学依据。

海岛型旅游度假区旅游环境容量研究--以分界洲岛为例

指出了海南分界洲岛为典型的海岛型旅游度假区,以分界洲岛为例,探讨了分界洲岛的旅游环境容量情况,主要从该岛的生态环境容量、功能设施环境容量、旅游空间环境容量和旅游社会环境容量4个指标进行了测算和分析。结果表明:除旅游空间环境容量外,其余3项旅游生态环境容量、功能设施环境容量以及旅游社会环境容量均存在不同程度的超载。根据上述研究结果,提出了促进分界洲岛旅游环境容量建设的策略,并为分界洲岛旅游的开发和发展提供了一些措施和建议。

终端行为可信评估及其访问控制方法研究

针对开放网络环境下重要信息系统资源高安全等级的访问控制需求,提出一种基于环境度量和行为评估的访问控制模型,该模型基于环境信任度对终端计算环境进行安全分级,基于多实体贝叶斯网络综合用户行为的多种属性对用户行为实施动态评估,整合了环境可信度和行为模式、资源访问、系统运行状态等行为表现属性,能较全面地对用户行为进行评估;模型采用条件规则和授权规则相结合的安全规则,实现对资源访问行为动态的访问控制.与现有的模型相比,提出的访问控制模型能够更好地适应环境的多变性和用户行为的复杂性,信任评价方法更具有可计算性和合理性.

进出口贸易中隐含碳量对环境影响的度量及中美比较

国际贸易中,伴随着产品的流动,碳排放也发生了转移,对各贸易国的环境带来影响。对于这个问题,本文建立了外贸隐含碳对本国环境影响力的度量指标:外贸碳贡献度、外贸碳相关度、外贸碳损失度及外贸碳拖累度,来描述一国与世界的碳交换程度及对本国环境的影响。同时,根据这些指标对中美两国的国际贸易对本国环境的影响进行了实证研究,并分析比较了两国国际贸易中碳交换特征。最后针对我国的贸易碳的环境影响提出了政策建议。

Effect of Environmental Gradients on the Quantity and Quality of Fallen Logs in Tsuga longibracteata Forest in Tianbaoyan National Nature Reserve, Fujian Province,China

We investigated the quantity and quality 0f fallen l0gs in different Tsuga l0ngibracteata f0rest c0mmunities in the Tianba0yan Nati0nal Nature Reserve. We used redundancy analysis t0 determine the spatial distributi0n 0f fallen l0gs in the different f0rest c0mmunities and t0 analyze the relati0nships am0ng stand structure, t0p0graphic fact0rs and human disturbance. The v0lume, c0vered area, mean l0g length and number 0f fallen l0gs differed significantly am0ng f0rest types （P 〈 0.05）, but mean diameter at breast height sh0wed n0 significant difference （P 〉 0.05）. The l0g v0lume and c0vered area in different f0rest types sh0wed the f0ll0wing trend： T. l0ngibracteata pure f0rest 〈 T. l0ngibracteata ＋ Olig0staehyum scabrifl0rur 〈 T. l0ngibraeteata ＋ hardw00d 〈 Rh0d0dendr0n simiarum ＋ T. l0ngibraeteata 〈 T. l0ngibraeteata ＋ Phyll0stachys heter0cycla pubescens. The spatial distributi0n patterns 0f l0gs quantity and quality indicated that l0g v0lume and c0vered area were str0ngly affected by envir0nmental fact0rs in the f0ll0wing 0rder： human disturbance 〉 elevati0n 〉 sl0pe p0siti0n 〉 b0le height 〉 tree height 〉 sl0pe aspect 〉 density 〉 basal area 〉 sl0pe gradient. The relative c0ntributi0n 0f envir0nmental variables 0n the t0tal variance was t0p0graphy （76%） 〉 disturbance （42%） 〉 stand structure （35%）. T0p0graphy and disturbance c0mbined explained 8.2% 0f the variance. Fallen l0~s auantitv and aualitvwere negatively related t0 elevati0n and sl0pe p0siti0n, and p0sitively ass0ciated t0 human disturbance. The l0g v0lume decreased fr0m n0rthern t0 s0uthern sl0pes. Envir0nmental fact0rs had the highest impact 0n class I （slightly decayed）, and l0west impact 0n class V （highly decayed）.

Dynamics of Motorized Vehicle Flow under Mixed Traffic Circumstance

To study the dynamics of mixed traffic flow consisting of motorized and non-motorized vehicles, a carfollowing model based on the principle of collision free and cautious driving is proposed. Lateral friction and overlapping driving are introduced to describe the interactions between motorized vehicles and non-motorized vehicles. By numerical simulations, the flux-density relation, the temporal-spatial dynamics, and the velocity evolution are investigated in detail The results indicate non-motorized vehicles have a significant impact on the motorized vehicle flow and cause the maximum flux to decline by about 13%. Non-motorized vehicles can decrease the motorized vehicle velocity and cause velocity oscillation when the motorized vehicle density is low. Moreover, non-motorized vehicles show a significant damping effect on the oscillating velocity when the density is medium and high, and such an effect weakens as motorized vehicle density increases. The results also stress the necessity for separating motorized vehicles from non-motorized vehicles.

Grey associated analysis of the underground water quality effected by the leaching water of dumping area or hillock of coal mine

The underground water has been contaminated seriously by the leaching water of dumping area or hillock. To determine the pollution limits of underground water, author took samples in the study area, analyzed samples for water quality, assessed the water quality of each monitoring point by the grey associated analysis method, and gave out the classifications of the underground water quality of the study area. Comparing with fuzzy comprehensive appraisal method, it is demonstrated that grey associated analysis method is applied easily, because of its clear concept, simple and convenient calculation and excellently operation.

Estimating the Operation Status of Steam Cracking Furnace Using Numerical Simulation with Combustion Models

An accurate and complete geometric model was constructed to simulate the combustion, flow and temperature environment in the radiant section of the steam cracking furnace. Simulation of flow and radiation status has utilized the standard k-ε model and P1 model. The finite-rate/eddy-dissipation (finite-rate/ED) combustion model and non-premixed combustion model were both used to simulate accurately the combustion and the operation status of the steam cracking furnace. Three different surfaces of the steam cracking furnace were obtained from the simulation, namely:the flue gas temperature field of the entrance surface in long flame burners, the central surface location of tubes, and the crossover section surface. Detailed information on the flue gas temperature and the mass concentration fraction of these different surfaces in the steam cracking furnace can also be obtained by the simulation. This paper analyzed and compared the simulation results with the two combustion models, estimated the operation status of the steam cracking furnace, and reported that the finite-rate/ED model is appropriate to simulate the steam cracking furnace by comparing key simulation data with actual test data. This work has also provided a theoretical basis for simulating and operating the steam cracking furnace.

Firework Induced Large Increase in Trace Gases and Black Carbon at Dibrugarh, India

Religious, occasional and annual fire work festivals worldwide are found to introduce high concentrations of pollutant gases and particulate matter into the atmosphere. These in turn alters the air quality of a region in the short and long time scales and affect human health adversely. The effect of fireworks on short-term variation in air quality of an urban location Dibrugarh, set amidst the rural environment of north-east India, was assessed from the ambient concentrations of 03, SO2, NOx, CO and BC （black carbon） during the Diwali festival during Nov. 13-14, 2012. The firework activity in general peaks during evening to midnight hours. Substantial increase in concentrations of O3, SO2, NOx, CO and BC was observed during the peak hours of firework activity （16：00 h to 22：00 h） in the Day 1 and Day 2 of the Diwali festival. However, the increase in concentrations from the background level was found to be highest on the post-Diwali day due to their accumulation in the atmosphere. The firework activity has not affected the regular diurnal pattern of the measured species during this episode.

Temperature Tolerance of Large Yellow Croaker,Pseudosciaena Crocea(Richardson)Associated with Summer Season

L ethal temperature tolerance was determined for about 8 cm, age 0 Pseudosciaena crocea using both slow heating and rapid transfer protocol. The acclimatization temperature was 28 ℃ with summer season, lethal temperature ( LT50 value ) of slow heating protocol ( CTMax ) was 35.0 ℃, and the upper and lower incipient lethal temperatures of rapid transfer protocol were 34.2 ℃ and 17.5 ℃ respectively.

The Relationship between Major Components of PM2.5 and Meteorological Factors in Urban Tokyo, Japan

In this research, the main purpose is to estimate the variation of PM2.5 mass concentration and study the influence of meteorological characteristics on major components of PM2.5 concentrations in urban Tokyo, Japan. The results shown that the annual mean mass concentration of PM2.5 in urban Tokyo was higher than JEQS （Japanese Environmental Quality Standard） of the MOEJ （Ministry of the Environment Japan） （15 μg/m^3）, and 41.1% of the daily PM2.5 mass concentration exceeded the annual JEQS concentration during observation period. The major components of PM2.5 including SO4^2-, NO3^-, NH4^＋, OC and EC were tightly related to the meteorological conditions, the correlations results shown that the wind speed and relative humidity had significant correlations with major components of PM2.5 than the other meteorological factors. Higher relative humidity, windless and less rainfall conditions were favorable for elimination of PM2.5 concentration. Higher temperature was beneficial to the formation of SO42＂, but higher temperature and stronger sunshine duration were not conducive to the formation of NO3^-.

Changing Wetland Environment Based on Water and Soil Quality Analysis of Selected Wetlands, Assam, India

Wetland environment of Assam is fast changing due to encroachments, dumping of solid and liquid wastes, excessive use of wetland water, over exploitation of wetland resources, overgrazing, over fishing, hunting, poaching, unscientific construction of engineering structures across and along the wetlands, unscientific land use in surrounding areas and various human interferences. On the other hand wetlands play an important role in charging ground water table, sinking of carbon, providing livelihood to thousands of people through fishing, collecting edible plants, agriculture, irrigation and commercial fisheries, besides enrich biodiversity and maintaining environmental quality of a region. The life of wetlands depends on the quantity and quality of water. Any change in water quality and quantity affect the biotic regime of the wetlands. Fish and other aquatic animals and plants found in all levels （floating, rooted, submergent and emergent etc.） are affected by the changes, which are taking place in wetland water. The present study concerns in understanding the environmental quality of the wetlands in Dimoria region of Kamrup （Metro） district, Assam based primarily on the water and soil quality of selected wetlands viz. Jiong, Parkhali, Bomani and Duani.

A review of chemical absorption of carbon dioxide for biogas upgrading

Significant attention has been given to biogas production, purification and upgrading as a renewable and clean fuel supplement. Biogas is a product of an anaerobic digestion process comprising methane, carbon dioxide,and trace amounts of other gases. Biogas purification removes trace gases in biogas for safe utilisation. Biogas upgrading produces methane-rich biogas by removing bulk carbon dioxide from the gas mixture. Several carbon dioxide removal techniques can be applied for biogas upgrading. However, chemical absorption of carbon dioxide for biogas upgrading is of special significance due to its operation at ambient or near ambient temperature and pressure, thus reducing energy consumption. This paper reviews the chemical absorption of carbon dioxide using amine scrubbing, caustic solvent scrubbing, and amino acid salt solution scrubbing. Each of these techniques for biogas upgrading is discussed. The paper concludes that an optimised implementation of the chemical absorption techniques for biogas upgrading requires further research.

Impact of Workspace Design in Indian Context on Occupant＇s Behavior, to Enhance Efficiency and Comfort

The environmental psychology ofa workspace is a rich and diverse field of study that is growing fast and gaining popularity. The indoor environmental factors in workspaces should follow functional as well as behavioral requirements as the spaces are designed as per the user＇s requirements, needs and aspirations. These play a major role in achieving behavioral impact on the user, as sense of well-being in the environment and physical comfort in the space enhances the productivity and efficiency of the user of the space. The slow and gradual importance of this issue in workspace design with Indian context, post occupancy evaluation can be adjudged as a permanent tool for improving indoor environment in buildings. Occupants should be used as a benchmark of evaluation, showing correlation of physical measurements and subjective parameters. It also suggests recommendations to improve quality of indoor environment in office buildings with analytical study, an important step in post occupancy evaluation. The objective of the paper is to inquire how people experience environmental psychology of the workspace as the determinants are efficiency, productivity and comfort. The success of any design depends upon the degree to which it creates an interface between the user and the environment.

Environmental life cycle assessment of Indian coal-fired power plants

Coal is the backbone of the Indian power sector. The coal-fired power plants remain the largest emitters of carbon dioxide, sulfur dioxide and substantial amounts of nitrogen oxides, which are associated with climate and health impacts. Various CO2 mitigation technologies （carbon capture and storage--CCS） and SO2/NOx mitigation technologies （flue gas desulfurization and selective catalytic reduction） have been employed to reduce the environmental impacts of the coal-fired power plants. Therefore, it is imperative to understand the feasibility of various mitigation technologies employed. This paper attempts to perform environmental life cycle assessment （LCA） of Indian coal-fired power plant with and without CO2, SO2 and NOx mitigation controls. The study develops new normalization factors for India in various damage categories, using the Indian emissions and energy consumption data, coupled with the emissions and particulate emission to come up with a final environmental impact of coal-fired electricity. The results show a large degree of dependence on the perspective of assessment used. The impact of sensitivities of individual substances and the effect of plant efficiency on the final LCA results is also studied.

Influencing factors of infrared surveying in roadway

The main factors that affect infrared surveying in roadway include that property of rock, electromechanical equipments running, environmental temperature, hydrogeology and support material etc. This paper sums up the expression features of these disturbing factor through theoretical analysis and actual measurement contrasts and considers that some tunnel section does not suit to go on infrared survey, for instance, soft rock meets water to expanse, and surround rock has obviously pouring water. The basic methods had made evading disturbing of electromechanical equipments, environmental temperature and protect material etc to become possible. It is helpful that offers infrared surveying technical service for production safety better in roadway.

Verification of the stomatal conductance of Nebbiolo grapevine

Wine is one of the most important Italian export products,and Nebbiolo is one of the most respected Italian grapes. In the summer of 2007,a measurement campaign was carried out in a Nebbiolo vineyard located in Vezza d’Alba,near Cuneo,Italy. Using a gauge of trade gases and some other instruments,we recorded the stomatal conductance and also some physiological parameters useful for estimating the dependence of stomatal conductance on environmental variables. The goal of this experiment was improving the parameterization of grapevine evapotranspiration through the assessment of the stomatal conductance and,in particular,of the functional dependence of the stomatal conductance on the following variables:the photosynthetically active radiation,the atmospheric temperature,the atmospheric moisture deficit,and the carbon dioxide concentration. The observations allowed us to check and,in some cases,to adapt the existing general parameterizations found in literature. The results showed some significant differences with the existing parameterizations concerning the atmospheric temperature,the atmospheric moisture deficit,and the carbon dioxide concentration. The parameterizations obtained in this experiment,although referring to a specific plant and site(namely the Nebbiolo at Vezza d’Alba),could allow assessment of the best environmental conditions under which the Nebbiolo grapevine production is the best,and in future could be tested for other grapevines or climates.