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SCHEME DESIGN AND ECONOMIC ANALYSIS ON small-scale BIOGAS LIQUEFACTION CYCLE

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SCHEME DESIGN AND ECONOMIC ANALYSIS ON SMALL-SCALE BIOGAS LI...

Factors that affect the assembly of ground-dwelling beetles at small scales in primary mixed broadleaved-Korean pine forests in north-east China

生物质能源技术国际会议

作者： Qing-hu FAN,Hong-yan LI,Quan-sen YIN,Jie-shi CUI,Lin-xiangJIA (Institute of Cryogenics and Superconductivity Technology,Harbin Institute of Technology, Harbin,150080,Heilongjiang,China)

The biogas has important practical significance in solving the energy crisis as a kind of clean,renewable biological energy of *** the large-scale concentratedness of the biogas is produced,the liquefaction of the biogas is extremely urgent in technical research in *** to the characteristic of the biogas,on the basis of mature natural gas purification and liquefaction technology,this paper discussed the small-scale biogas liquefaction system of the double purposes to purification,liquefaction and recovery of liquefied *** paper provides the liquefaction biogas plant process chart,and system analysis,and the effects on the key ***,the thermal parameters of the liquefaction cycle are ***,the economic investment of 5000Nm·d small-scale biogas liquefaction cycle is emphatically analyzed,and the conclusion is that the payback period of the investment on the biogas liquefaction equipments is only 2.3 *** result provides guidelines for the project feasibility analysis and design of the small-scale biogas liquefaction device.

关键词： small scale Biogas Liquefaction Design Economic Analysis Nitrogen Expander Cycle

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Soil Ecology Letters 2020年第1期2卷 47-60页

作者： Meixiang Gao Zhihong Qiao Hongyu Hou Guangze Jin Donghui Wu College of Geographical Sciences Harbin Normal UniversityHarbin 150025China Heilongjiang Province Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Regions Harbin Normal UniversityHarbin 150025China Center for Ecological Research Northeast Forestry UniversityHarbin 150040China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130012China Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchun 130117China

Disentangling the relative roles of environmental and spatial processes in community assembly is a major task of community *** is necessary to uncover this question at multiple spatial scales;however,the relative importance of spatial and environmental processes on ground-dwelling beetle assembly at a small scale is still *** on two permanent plots(each 300 m)located in primary mixed broadleaved-Korean pine forests,the topographic,soil,and plant factors were collected,and the spatial variables(MEMs,distancebased Moran’s eigenvector maps)were calculated.A redundancy analysis(RDA)was used to evaluate the influence of topographic,soil,and plant variables on ground-dwelling beetle compositions.A variation partitioning analysis was used to quantify the relative contributions of environmental and spatial processes on the assembly of ground-dwelling *** results of the RDA reported that the soil,plant,and topographic variables affected Staphylinidae and Silphidae beetle compositions in both *** to the results of variation partitioning,pure soil and plant variables were important for the assembly of Silphidae beetles in the LS *** contributions of pure topographic,soil,and plant variables were significantly lower than those of pure spatial *** contributions of pure spatial variables were significant for the assembly of Staphylinidae and Silphidae beetles in both *** addition,the relative importance of environmental and spatial processes was not significantly changed after including more environmental variables and the unexplained ***,this study suggests that both spatial and environmental variables are important for the assembly of ground-dwelling beetle communities,while pure spatial variables are more important than pure environmental variables at a small scale(300 m).

关键词： Spatial variables Environmental variables small scale Staphylinidae beetles Silphidae beetles

Vibration of quadrilateral embedded multilayered graphene sheets based on nonlocal continuum models using the Galerkin method

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Acta Mechanica Sinica 2011年第6期27卷 967-976页

作者： H.Babaei A.R.Shahidi Department of Mechanical Engineering Isfahan University of Technology

Free vibration analysis of quadrilateral multilayered graphene sheets（MLGS） embedded in polymer matrix is carried out employing nonlocal continuum *** principle of virtual work is employed to derive the equations of *** Galerkin method in conjunction with the natural coordinates of the nanoplate is used as a basis for the *** dependence of small scale effect on thickness,elastic modulus,polymer matrix stiffness and interaction coefficient between two adjacent sheets is *** non-dimensional natural frequencies of skew,rhombic,trapezoidal and rectangular MLGS are obtained with various geometrical parameters and mode numbers taken into account,and for each case the effects of the small length scale are investigated.

关键词： small scale Free vibration. Quadrilateral multilayered graphene sheet. Polymer matrix. Nonlocal elasticity theory

Relationship between plant species diversity and patch characteristics in a marsh in the Sangjiang Plain,China—Using Yaluhe farm as an example

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Progress in Natural Science:Materials International 2007年第6期17卷 664-669页

作者： Sun Zhonglin1, Xing Fu1,2, Lu Xianguo2, Xu Kun1, Yu Lili1 and Ni Hongwei3(1. Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun 130024, China 2. Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012, China 3. Natural Resources Instute of Heilongjiang Academy of Sciences, Harbin 150040, China) [a]Key Laboratory of Vegetation Ecology Ministry of Education Changchun China [b]Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchum China [c]Natural Resources Instute of Heilongjiang Academy of Sciences Harbin China

Based on Quick Bird satellite image data, the present study examined small-scale herbaceous community patches in the marsh of the Sanjiang Plain and measured patch characteristics such as the area, perimeter and shape by GPS. The coenological characteristics of the patches were investigated using quadrat method, and the vascular plant species were recorded using transect method. A total of 219 plant species were recorded, which represents 12.2% of the vascular flora in Heilongjiang Province. Our results showed that species number S correlated with patch area and perimeter; richness index (R) correlated with patch perimeter; Simpson index (D) correlated with patch area and perimeter/area; Shannon-Wiener index (H′) correlated with patch area, perimeter and perimeter/area; Evenness index (Jsw) correlated with perimeter/area. Both S and R have significant difference between different size of patches. Plant diversity in the small-scale herbaceous communities tended to increase with the patch area and perimeter. We concluded that edge effects and the habitat heterogeneity of the patches are important in determining the number of species. The relative smoothness of the patch edges also affects the plant diversity of the patches. The richness of plant species in the marsh in the Sanjiang Plain is highly sensitive to the small-scale patches, which continues to play an important role in preserving plant diversity in the local area.

关键词： marsh in Sanjiang Plain plant diversity community patch habitat fragmentation small scale edge effect.

Cooperative localization for next-generation converged networks with closed-form solution

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 56-61页

作者： ZHANG Yi-heng CUI Qi-mei ZHANG Ping TAO Xiao-feng Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Research Institute of Highway (RIOH) Transport Consulats Ltd Beijing 100088 China

In this article, a novel cooperative wireless localization scheme based on information fusion is proposed. The scheme combines large-scale arrival time and small-scale distance measurements obtained from the next-generation converged networks. The maximum likelihood （ML） estimate of the terminal＇s position is derived with closed-form solution, and the Cramer-Rao lower bound （CRLB） of the estimate error is investigated. Both theoretical analysis and simulation results verify that the proposed localization scheme can significantly enhance the location precision. Moreover, the mean square error of position estimate approximates the CRLB when the number of reference stations increases, which indicates that the proposed ML estimator is asymptotically efficient.

关键词： cooperative localization time of arrival (TOA) next-generation converged network large scale small scale

Relative Contributions of Spatial and Environmental Processes and Biotic Interactions in a Soil Collembolan Community

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Chinese Geographical Science 2015年第5期25卷 582-590页

作者： SHA Di GAO Meixiang SUN Xin WU Donghui ZHANG Xueping Key Laboratory of Remote Sensing Monitoring of Geographic Environment College of Heilongjiang Province Harbin Normal University College of Geographical Science Harbin Normal University Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Understanding the underlying processes of how communities are structured remains a central question in community ecology. However, the mechanisms of the soil animal community are still unclear, especially for communities on a small scale. To evaluate the relative roles of biotic interactions and environmental and spatial processes in a soil collembolan community, a field experiment was carried out on a small scale(50 m) in the farmland ecosystem of the Sanjiang Plain, Northeast China. In August and October, 2011, we took 100 samples each month in a 50 m × 50 m plot using a spatially delimited sampling design. Variation partitioning was used to quantify the relative contributions of the spatial and environmental variables. A null model was selected to test for the non-randomness pattern of species co-occurrence and body size in assemblages of collembolans and to test whether the pattern observed was the result of environmental or biotic processes that structured the community on a small scale. The results showed that large variance was accounted for by spatial variables(18.99% in August and 21.83% in October, both were significant). There were relatively lower effects of environmental variation(3.56% in August and 1.45% in October, neither was significant), while the soil water content, soil p H and soybean height explained a significant portion of the variance that was observed in the spatial pattern of the collembolan community. Furthermore, the null model revealed more co-occurrence than expected by chance, suggesting that collembolan communities had a non-random co-occurrence pattern in both August and October. Additionally, environmental niche overlap and the body size ratio of co-occurrence showed that interspecific competition was not influential in collembolan community structuring. Considering all of the results together, the contributions of spatial and environmental processes were stronger than biotic interactions in the small-scale structuring of a soil c

关键词： spatial process environmental filtering biotic interactions variation partitioning small scale collembolan community

Are China＇s Farms Growing？

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China & World Economy 2016年第1期24卷 41-62页

作者： Xianqing Ji Tianjin Normal University Tianjin China

China＇s agricultural sector faces challenges because most farms are still small scale. China＇s policy is to encourage the consolidation o f farms and promote farms that are larger in scale. A question that arises is： Are China＇s farms growing？ The goal of the present paper is to determine whether large farms in China have emerged or iffarms remain small. To meet this goal, we systematically document the trends in the operational sizes of China＇s farms and measure the determinants of changes in farm size. Using a nationally representative dataset, the study shows that in 2013 China＇s farming sector was still mostly characterized by small-scale farms. However, at the same time, there is an emerging class of middle-sized and larger-sized farms. Most large farms are being run by households but there is a set of large farms that are companylcooperative-run. Today, farmers on larger farms are younger and better educated than the average farmer.

关键词： emergence large scale operational farm size rural China small scale

Effect of Physical Environment on the Behaviors of Residents with Dementia： A Comparison between a small-Group Unit and a Traditional Care Unit

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Journal of Civil Engineering and Architecture 2014年第11期8卷 1353-1363页

作者： Sookyoung Lee Habib Chaudhury Soojin Lee Department of Environmental Design for the Elderly Research Center Design & Health Stockholm 16966 Sweden Department of Gerontology Simon Fraser University Vancouver BC V6B 5K3 Canada Symbiotic Life-Tech Research Center Yonsei University Seoul 120-749 Korea

This is a comparative study examining the influence of a small-scale dementia unit and a traditional dementia unit on behaviors of the residents. The small-scale unit and the traditional unit were selected through two phases in Vancouver, Canada. Seven residents from each facility completed the study. Physical environmental assessments were performed using two tools： PEAP （professional environmental assessment protocol） and TESS-NH （therapeutic environment screening survey for nursing homes）. For the assessment of residents＇ behaviors, three assessment tools were used： MOSES （multidimensional observation scale for elderly subjects）, MDS （minimum data set） and DCM （dementia care mapping）. The study found that the residents living in a small-scale environment were more engaged in activities and more likely to respond in understanding their fellow residents. Residents living in a traditional long-term care exhibited fewer signs of social interaction. The findings suggest that a small-scale homelike environment could positively influence people with dementia to be more engaged in social exchanges and activities, and consequently help in reducing their withdrawn behavior.

关键词： Dementia small scale dementia unit homelike environment long-term care.

Establishment of small Centralized Collection Processing Service System of Scattered Farming Waste

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Meteorological and Environmental Research 2015年第4期6卷 14-17页

作者： Bai Yanfei Wang Zichen Wu Hao Wang Haiqin Shen Jianning Wu Tianxiang Guan Yongxiang Liang Yonghong Jiangsu Station of Agro-Ecological Monitoring and Protection Circular Agricultural Research Center Jiangsu Academy of Agricultural Sciences

In order to advance pollution control and promote agricultural source pollution reduction of Jiangsu Province, based on the practical expe- rience of Lijia Livestock and Poultry Manure Processing Center in Wujin District, Changzhou City, Jiangsu Province, new ways of controlling small scattered livestock and poultry breeding pollution, with characteristics of ＂ unified collection, centralized processing, social services, and compre- hensive utilization＂, were discussed through establishing the collection processing service system, innovating operation system and mechanism, and transforming the mode of government supervision and management.

关键词： small scale Livestock and poultry breeding Collection System Comprehensive utilization China