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Impacts of LUCC processes on potential land productivity.in China in the 1990s

Science China Earth Sciences 2005年第8期48卷 1259-1269页

作者： LIU Jiyuan XU Xinliang ZHUANG Dafang GAO Zhiqiang Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Using meteorological data and RS dynamic land-use observation data set, the po-tential land productivity.that is limited by solar radiation and temperature is estimated and the impacts of recent LUCC processes on it are analyzed in this paper. The results show that the influence of LUCC processes on potential land productivity.change has extensive and unbal-anced characteristics. It generally reduces the productivity.in South China and increases it in North China, and the overall effect is increasing the total productivity.by 26.22 million tons. The farmland reclamation and original farmlands losses are the primary causes that led potential land productivity.to change. The reclamation mostly distributed in arable-pasture and arable-forest transitional zones and oasises in northwestern China has made total productivity.increase by 83.35 million tons, accounting for 3.50% of the overall output. The losses of original farmlands driven by built-up areas invading and occupying arable land are mostly distributed in the regions which have rapid economic development, e.g. Huang-Huai-Hai plain, Yangtze River delta, Zhu-jiang delta, central part of Gansu, southeast coastal region, southeast of Sichuan Basin and Urumqi-Shihezi. It has led the total productivity.to decrease 57.13 million tons, which is 2.40% of the overall output.

关键词： land-use change, potential land productivity. photosynthetic productivity. photosynthetic thermal pro-ductivity, total photosynthetic thermal productivity.

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Perceived Indoor Discomfort, Performance and productivity

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Journal of Civil Engineering and Architecture 2012年第11期6卷 1514-1522页

作者： Ingrid Senitkova Miroslav Badida Faculty of Mechanical Engineering Technical University of Kosice Kosice 042 00 Slovakia

Even all indoor environmental standards are met the users are usually not satisfied and perceived discomfort is occurred in the smart office buildings. The most frequently cause of discomfort in smart buildings is overrun of intelligence. There are physical and psychological factors that influenced building users＇ comfort. An indoor air quality seems to be one of the main problems of smart office buildings. In Slovakia the office buildings relating to indoor environment European standard are mostly evaluated as the non-low polluting buildings. The pollution from building as well as the pollution from occupancy and using was respected. The odor intensity and indoor air acceptability were assessed by a sensory panel. The concentrations of total volatile organic compounds and carbon dioxide were measured. The odors from building materials studied under different air change rate are presented in this paper. The case study of indoor air acceptability concerning to indoor odors under occupancy and its affect on perceived air quality influenced by air change rate are also presented in this paper.

关键词： Office buildings perceived discomfort air quality work performance productivity.

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The Study of Alfalfa-Sinorhizobium meliloti Symbiosis productivity.under Different Water Conditions and the Influence of the Legume Seeds Lectin

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Journal of Agricultural Science and Technology(B) 2011年第3期1卷 454-457页

作者： S. Ya. Kots L. M. Mykhalkiv P. M. Mamenko M. V. Volkogon Department of Symbiotic Nitrogen Fixation Institute of Plant Physiology and Genetics NAS of Ukraine 31/17 Vasylkivska str. Kyiv 03022. Ukraine

The paper studies the effect of incubation of rhizobia with soybean seeds lectin on formation and functioning of alfalafa-Sinorhizobium meliloti symbiosis under the optimal water supply and drought conditions. It was shown that the addition of lectin to the inoculation compositions intensifies physiological processes in alfalfa plants： increases nitrogen fixing activity of symbiosis, nodule number on roots, as well as chlorophyll and carotenoid content in leaves, enhances plant growth during budding-fruiting period and reduces the negative effect of drought on alfalfa productivity.

关键词： Symbiosis alfalfa soybean seeds lectin drought productivity.

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Enhance Mining System Reliability through System Integration Approach

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Journal of Mechanics Engineering and Automation 2013年第11期3卷 694-701页

作者： Yong Sun Xingsheng Li Hua Guo CSIRO Earth Science and Resource Engineering Kenmore QLD 4069 Australia

The reliability of mining systems is generally low due to their harsh working conditions. Currently, efforts for improving mining system reliability are often made in isolation. This practice could substantially limit the effectiveness of the efforts on overall reliability improvement of the mining system. To enhance the overall reliability of mining systems, an integrated improvement approach is necessary. In this paper, we developed a framework for integrated mining system reliability improvement to address this issue. In this framework, there are five major components including data integration, business process integration, hardware integration, software integration and analysis/decision integration, but we only focus on the integrated reliability analysis which is important to the analysis/decision integration. The reliability analysis considers the interactions between machines, and the impacts of design, operation, maintenance, automation and working environment on the overall system reliability. These multiple interactions present a big challenge to accurate reliability prediction. In this paper, we for the first time systematically investigated integrated reliability analysis approaches for dealing with this challenge using novel models and methods, including covariate hazard models, intelligent reliability prediction approach and complex system modeling methods. While these models and methods have found some successful applications in other industries, they in general have not been effectively used for the reliability analysis of mining systems. Our study results show that the system integration approach is applicable to mining systems and can be used for developing a computer aided integration system for the implementation of the integrated reliability improvement approach.

关键词： Reliability mining system integration failure rate safety productivity.

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Corn Water Variables Assessments from Earth Observation Data in the Sao Paulo State, Southeast Brazil

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Journal of Hydraulic Engineering 2015年第1期1卷 1-11页

作者： Antonio Heriberto de Castro Teixeira Femando Braz Tangerino Hemandez Ricardo Guimaraes Andrade Janice Freitas Leivas Daniel de Castro Victoria Edson Luis Bolfe Department of Geosciences Embrapa Satellite Monitoring Campinas Sao Paulo 13070-115 Brazil Department of Hydrology Sao Paulo State University llha Solteira Sao Paulo 15.385-000 Sao Paulo Brazil

Landsat satellite images and agrometeorological data were used together for modelling the crop coefficient （Kc） in irrigation pivots composed by a mixture of corn hybrids from a commercial farm for grains and silage, located at the northwestern side of Sao Paulo state, Brazil. After developing relationships between Kc and the accumulated degree-days （DDac） and having yield data for 2012 available, they were applied in the whole state, to upscale the crop water variables, during the GS （growing seasons） of a second-harvest crop from March to August. Spatial thermohydrological differences among the main corn growing regions were clear. The largest CWP （crop water productivity. values and SD （standard deviations） were for Itapetininga with an average value of 1.60 ± 0.43 kg m-3, while the lowest ones were for Presidente Prudente （0.81±0.21 kg m-3）. As corn is important for these growing regions, being inside of the priorities from the Brazilian Ministry of Agriculture, these results should be considered for a rational exploration, including both, irrigation and rainfed conditions, as the actual water scarcity can bring much competition with other non-agricultural sectors.

关键词： Crop coefficient, degree-days, WI (water indicator), crop water productivity.

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Performance Evaluation of Bioethanol Production through Continuous Fermentation with a Settling Unit

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Journal of Energy and Power Engineering 2013年第11期7卷 2083-2088页

作者： Mark Ian Nelson Norhayati Hamzah School of Mathematics and Applied Statistics University of Wollongong Wollongong 2522 NSW Australia Department of Mathematics University Brunei Darussalam Bandar Seri Begawan BE 1410 Brunei

This paper analyses a model for the production of bioethanol that has been calibrated against laboratory data by previous researchers. The authors investigate the improvement in productivity.that can be obtained when a centrifuge is used to recycle cells that would otherwise leave the reactor system in the efficient stream. The authors compare the performance of a double reactor cascade, possible employing a settling unit, against that of a single reactor. For the former case, this paper considers the reactor configuration in which the settling unit recycles from the effluent stream of a reactor back in the influent of the same reactor.

关键词： Bioethanol mathematical modelling productivity.

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Effect of Rust Disease on Photosynthetic Rate of Wheat Plant

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Journal of Agricultural Science and Technology(B) 2015年第7期5卷 486-490页

作者： Sevda Abdulbagiyeva Atif Zamanov Javanshir Talai Tofig Allahverdiyev Research Institute of Crop Husbandry Pirshaqi Settlemen Sovkhoz-2 Baku AZ1098 Azerbaijan

The purpose of this research was to study the influence of rust diseases on photosynthetic rate of the created local varieties and introduced variety samples of wheat. Experiment was carried out with two variants-control and 25% Tilt treatment. The 25% solution of Tilt was used to prevent disease infection. The photosynthetic rate was measured by T-type URAS-2 infrared gas analyzer （made＇ in Germany）. Disease infection rate was determined based on the Cobby balling scale. Ontogenetic and daily rate of photosynthesis by effect of the disease were decreased. The amount of assimilated CO2 during the day and vegetation period linearly depends on the disease infection degree. At the same time, the activation of non-infected parts＇ photosynthetic rate of some varieties was observed. The difference reaches up to 87% between the variants as a result of the rapid aging of photosynthesis apparatus.

关键词： Wheat plant breeding photosynthesis productivity.

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Strategies for farmers and policy makers to control nitro-gen losses whilst maintaining crop production

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Science China(Life Sciences) 2005年第Z2期48卷 710-719页

作者： Keith W.T.Goulding Agriculture and the Environment Division Rothamsted Research HarpendenHertfordshireAL5 2JQUK

The nitrogen (N) cycle is essentially 'leaky'. The losses of small amounts of nitrate to waters and of ammonia and nitrous oxide to the atmosphere are a part of the global biogeo-chemical N cycle. However, intensive agricultural production, industry and vehicle use have more than doubled the amount of 'reactive' N in the environment, resulting in eutrophication, ecosystem change and health concerns. Research has identified agricultural practices that cause large losses of N and, in some cases, developed solutions. This paper discusses the problems of maintaining productivity.while reducing N losses, compares conventional with low input (integrated) and organic farming systems, and discusses wider options. It also looks at the need to integrate studies on N with other environmental impacts, set in the context of the whole farm system, to provide truly sustainable agricultural systems.

关键词： Nitrogen cycle, farm systems, best management, environmental impact, productivity.

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Density of Standing of Plants at Cultivation of Cauliflower Seeds in Uzbekistan

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Journal of Agricultural Science and Technology 2011年第1期5卷 81-84页

作者： Sh. I. Asatov Department of Vegetable Growing Tashkent State Agrarian University Tashkent 100140 Uzbekistan

The results of researches aimed to establish the optimum growing space and density of standing of plants at cultivation of cauliflower seeds in Uzbekistan are stated in the article. Researches were spent in the suburb of Tashkent with a mid-early grade ＂Domestic＂. In experiences were compared 5 densities of standing （31746, 35714, 40806, 47620 and 57142 pieces/hectare） received at planting of sprouts with row-spacing of 70 sm and distance between plants in a row 25, 30, 35, 40 and 45 sm. Experiences were pawned in quadruple frequency with the area of an allotment 10 M2. 60-65 day sprouts were planted under film tunnel shelters on February 11-12. Film shelters were kept over plants till the end of March. Seed plants were grown up without formation. Experiences were accompanied by phonological control, calculation of leaves quantity, an establishment of average weight of a head, definition of quantity of the plants, which have given seeds, the account of a crop of seeds from a bush and of a unit of area. It has been defined that reception of seeds of a cauliflower at cultivation under film tunnels is quite possible in Uzbekistan. It is established that with representation of the big growing space the plants form more leaves, earlier and larger form the heads, develop the testicles acceleration and increase their seed efficiency. It has been revealed that the more plants thickness is, the bigger share of them does not give seeds. In this connection the greatest crop of seeds has been received at growing space 70x45 sm at which 31.7 thousand Pl/ha had been planted. It is proved that in the conditions of Uzbekistan it is possible to cultivate high-grade seeds of cauliflower with productivity.of 127-147 kg/ha.

关键词： Cauliflower density of standing growing space leaves heads flower-bearing shoots seed efficiency productivity.

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制度变迁与中国农业生产率的提高

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农业经济研究 2019年第12期

作者：张洪亮李心雅

以诺斯为代表的制度经济学家认为，一个国家的制度是决定其经济增长的关键性因素。一个国家的长期经济增长取决于生产能力的不断增长，农业发展也是如此。农业增长可以分解为两部分，一是生产要素投入水平的提高，二是生产要素生产率的... 详细信息

以诺斯为代表的制度经济学家认为，一个国家的制度是决定其经济增长的关键性因素。一个国家的长期经济增长取决于生产能力的不断增长，农业发展也是如此。农业增长可以分解为两部分，一是生产要素投入水平的提高，二是生产要素生产率的提高。长期来看，不论是整体经济的增长，还是工业或农业某个单独部门的增长，都不可能仅仅依赖要素投入的不断增加，而要以生产率的提高为增长的核心驱动力量。那么究竟是哪些因素推动了生产率的增长呢?正如Acemoglu在一系列文章中指出的，技术进步固然是推动经济增长的关键因素，但这只是经济增长的间接原因(approximate causes)，而制度才是经济增长的根本原因(fundamental causes)。自新中国成立以来，农业经济领域取得了显著的成就，也经历过生产率和产量增长的倒退，相比其他发达经济体，中国农业经济仍有巨大的潜力等待挖掘，这一切变化都伴随着制度的巨大变化。中国农业发展中出现的教训、取得的成就以及面临的挑战，为我们理解制度变迁与生产率变化之间的关系提供了一个鲜活的案例，对这个案例的深入分析不仅可以为提高农业生产率注入一定的“无形资本”，同时也可以丰富新制度经济学的内容。

关键词：制度农业生产率 Institution Agriculture productivity.

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