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Identifying the critical phosphorus balance for optimizing phosphorus input and regulating soil phosphorus effectiveness in a typical winter wheat-summer maize rotation system in North China
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作者 XU Meng-ze WANG Yu-hong +6 位作者 NIE Cai-e SONG Gui-pei XIN Su-ning LU Yan-li BAI You-lu ZHANG Yin-jie WANG Lei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3769-3782,共14页
Phosphorus(P)is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield.Excessive P fertilizer application is widespread in agricultural production,which no... Phosphorus(P)is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield.Excessive P fertilizer application is widespread in agricultural production,which not only wastes phosphate resources but also causes P accumulation and groundwater pollution.Here,we hypothesized that the apparent P balance of a crop system could be used as an indicator for identifying the critical P input in order to obtain a high yield with high phosphorus use efficiency(PUE).A 12-year field experiment with P fertilization rates of 0,45,90,135,180,and 225 kg P_(2)O_(5)ha^(-1)was conducted to determine the crop yield,PUE,and soil Olsen-P value response to P balance,and to optimize the P input.Annual yield stagnation occurred when the P fertilizer application exceeded a certain level,and high yield and PUE levels were achieved with annual P fertilizer application rates of 90-135 kg P_(2)O_(5)ha^(-1).A critical P balance range of 2.15-4.45 kg P ha^(-1)was recommended to achieve optimum yield with minimal environmental risk.The critical P input range estimated from the P balance was 95.7-101 kg P_(2)O_(5)ha^(-1),which improved relative yield(>90%)and PUE(90.0-94.9%).In addition,the P input-output balance helps in assessing future changes in Olsen-P values,which increased by 4.07 mg kg^(-1)of P for every 100 kg of P surplus.Overall,the P balance can be used as a critical indicator for P management in agriculture,providing a robust reference for limiting P excess and developing a more productive,efficient and environmentally friendly P fertilizer management strategy. 展开更多
关键词 yield of winter wheat and summer maize phosphorus balance phosphorus use efficiency OLSEN-P critical phosphorus application rate
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Balanced Scorecard and Efficiency: Design and Empirical Validation of a Strategic Map in the University by Means of DEA 被引量:1
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作者 Teresa García Valderrama Vanesa Rodríguez Cornejo Daniel Revuelta Bordoy 《American Journal of Operations Research》 2013年第1期30-52,共23页
The principal objective of the research reported in this article is to validate a Balanced Scorecard (BSC) model and a Strategic Map for the University by studying the relationships of efficiency between its dimension... The principal objective of the research reported in this article is to validate a Balanced Scorecard (BSC) model and a Strategic Map for the University by studying the relationships of efficiency between its dimensions. Subsequently, the validation is completed by establishing hypotheses of efficiency relationships between the perspectives proposed, employing Data Envelopment Analysis (DEA). Empirical evidence has been obtained on the validity of the proposed BSC for a unit of academic management in the university. The first contribution of this work is the establishment of a framework of analysis of the hypothetical cause-effect relationships in the BSC in university institutions. The second contribution is to obtain the determining factors of the performance in this type of institution and, therefore, the Strategic Map. Specifically, these factors are: the participation of teaching staff in innovation activities;the number of doctorate-level staff;the academic subjects and credits in the Virtual Campus;and the scores in the surveys of student satisfaction. With respect to research, the determining factors of the performance are: the research sexennials;the funding obtained from contracts with companies;the number of research projects obtained;their financing;and the participation of teachers in these projects. 展开更多
关键词 balanceD SCORECARD efficiency Data Envelopment Analysis UNIVERSITY
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Balanced Fertilization and the Effect of Fertilization on Water Use Efficiency of Upland Winter Wheat in Western Henan, China
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作者 LI GUIBAO LIU CHUNMING +4 位作者 SUN KEGANG BAO DEJUN ZHANG GUILAN LEI QUANKUI YAO YUQING and BU LIJIE (Soil and Fertilizer Institute, Henan Academy of Agricultural Sciences, Zhengzhou 450002 China)(Luoyang Institute of Agricultural Sciencea, Luoyang 471022 Ch 《Pedosphere》 SCIE CAS CSCD 1998年第4期361-366,共6页
A study on balanced fertilization was conducted by means of long-term field experiments, and a convenient table for balanced fertilization was compiled. The experimental results about the effect of fertilization on wa... A study on balanced fertilization was conducted by means of long-term field experiments, and a convenient table for balanced fertilization was compiled. The experimental results about the effect of fertilization on water use efficiency of upland wheat showed that the input of inorganic fertilizer should be reduced in dry years. 展开更多
关键词 施肥 水分利用效率 冬小麦 河南 平衡施肥 丘陵地区 营养平衡
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A Multi-Object Genetic Algorithm for the Assembly Line Balance Optimization in Garment Flexible Job Shop Scheduling
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作者 Junru Liu Yonggui Lv 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2421-2439,共19页
Numerous clothing enterprises in the market have a relatively low efficiency of assembly line planning due to insufficient optimization of bottleneck stations.As a result,the production efficiency of the enterprise is... Numerous clothing enterprises in the market have a relatively low efficiency of assembly line planning due to insufficient optimization of bottleneck stations.As a result,the production efficiency of the enterprise is not high,and the production organization is not up to expectations.Aiming at the problem of flexible process route planning in garment workshops,a multi-object genetic algorithm is proposed to solve the assembly line bal-ance optimization problem and minimize the machine adjustment path.The encoding method adopts the object-oriented path representation method,and the initial population is generated by random topology sorting based on an in-degree selection mechanism.The multi-object genetic algorithm improves the mutation and crossover operations according to the characteristics of the clothing process to avoid the generation of invalid offspring.In the iterative process,the bottleneck station is optimized by reasonable process splitting,and process allocation conforms to the strict limit of the station on the number of machines in order to improve the compilation efficiency.The effectiveness and feasibility of the multi-object genetic algorithm are proven by the analysis of clothing cases.Compared with the artificial allocation process,the compilation efficiency of MOGA is increased by more than 15%and completes the optimization of the minimum machine adjustment path.The results are in line with the expected optimization effect. 展开更多
关键词 Assembly line balance topological order genetic algorithm compilation efficiency pre-production scheduling
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An Analysis on Efficiency and Equity of Fixed-Time Ramp Metering 被引量:1
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作者 Ali Sercan Kesten Murat Ergün Tetsuo Yai 《Journal of Transportation Technologies》 2013年第2期48-56,共9页
Various traffic management strategies have been developed to alleviate the congestion on freeways. The equity issue has been considered as one of the major challenges for the implementation of some traffic control str... Various traffic management strategies have been developed to alleviate the congestion on freeways. The equity issue has been considered as one of the major challenges for the implementation of some traffic control strategies, especially ramp metering. This paper presents a comparative evaluation of the efficiency and equity performance of a traffic control strategies namely Fixed Time Ramp Metering (FTRM). Instead of focusing on a single equity measure and/or indicator, different approaches to the equity concept are discussed and various equity measures are examined. The equity and efficiency performance of traffic control strategies are compared and evaluated by incorporating them into the simulated corridor. The Bosporus Bridge of Istanbul O-1 Freeway, Turkey is used as a test-bed for the simulation model and the control strategy is employed through microscopic traffic flow simulation software, VISSIM AG. The findings from the simulations show that the equity and efficiency properties of the network vary with the measures and indicators taken into account. The results also suggest that the trade-off between equity and efficiency can be observed for some measures, whereas regarding to other measures the trade-off is not validated. 展开更多
关键词 TRAFFIC CONTROL STRATEGIES TRAFFIC Flow MICRO-SIMULATION equity in TRAFFIC CONTROL efficiency and equity Trade-Off
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Parallel Correlative Study of the Heat Balance Test Process for Testing the Efficiency of Turbo-Generators
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作者 Luqman Muhammed Audu Olugbenga Olanrewaju Noah +1 位作者 Ogaga Kenneth Ajaino Friday Chukwuyem Igbesi 《Energy and Power Engineering》 2016年第3期161-172,共12页
In order to prolong the life span of a turbo-generator plant and sustain its performance at high efficiency, it is subjected periodically to regular test to monitor the operational profile and efficiency of power conv... In order to prolong the life span of a turbo-generator plant and sustain its performance at high efficiency, it is subjected periodically to regular test to monitor the operational profile and efficiency of power conversion from mechanical energy to electrical energy. Analysis of these test data serves as a measure to indicate deviation from normal operation profile and deterioration of plant performance. This present work implemented the heat balance tests process to three turb- generator units in order to assess the harmony, consistency, and accuracy of results to establish parallel correlation for the test process. The test process involves carrying out a heat balance for the turbo-generators at 50%, 75% and 100% load respectively through the determination of the heat losses through the hydrogen coolers, bearing oil, seal oil and radiation and convention to the atmosphere. Some important results were presented in the paper. 展开更多
关键词 efficiency TURBO-GENERATOR TESTING Hydrogen-Cooled Heat balance
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Economically Optimal Rates and Nutrients Use Efficiency Indices of Maize to the Application of Different Rates of Nutrients in Central Rift Valley of Ethiopia
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作者 Israel Bekele 《Agricultural Sciences》 CAS 2022年第7期855-878,共24页
The use of balanced fertilizers in adequate amount is very important to increase crop productivity and production in Ethiopia. The study was executed to quantify maize (Zea mays L.) grain yield response to different r... The use of balanced fertilizers in adequate amount is very important to increase crop productivity and production in Ethiopia. The study was executed to quantify maize (Zea mays L.) grain yield response to different rates of nitrogen (N), phosphorus (P), potassium (K) and sulfur (S) under balanced fertilization of other nutrients. On farm trials were conducted at seven sites on 8 farmers’ fields in Negele Arsi districts, west Arsi zone of Oromia region for three consecutive cropping seasons (2014-2016). Six rates of N, P, S and eight rates of K treatments established separately for each nutrient were laid out in randomized complete block (RCB) design with three replicates per farm. Nutrient response function modelling showed that 184, 20 and 80 kg&#8226;ha<sup>&#8722;1</sup> were the agronomic optimum rate for N, P, and K, respectively. Mean agronomic efficiency (AE) of N, P and K were recorded at the lower rates of these nutrients, application of 46, 10 and 20 kg&#8226;ha<sup>&#8722;1</sup> N, P and K resulted in 19.1, 61.0, and 24 kg additional grain yield&#8226;kg<sup>&#8722;1</sup> N, P and K, respectively. Also, the mean partial factor productivity (PFP) of N, P and K were 77.6, 370 and 158 kg additional grain&#8226;kg<sup>&#8722;1</sup> applied N, P and K respectively. Economically optimal rate (EOR) of N, P and K were 48 - 114 kg&#8226;ha<sup>&#8722;1</sup> N with CP 8 - 3.5, 12 - 20 kg&#8226;ha<sup>&#8722;1</sup> P with CP 18 - 4.5 and 32 - 53 kg&#8226;ha<sup>&#8722;1</sup> K with CP 8-4, from these rates net returns of US$487.23 - 143.30, US$698.16 - 498.3 and US$359.31 - 193.63 could be obtained respectively. To conclude, application of 84, 12 and 40 kg&#8226;ha<sup>&#8722;1 </sup>N, P and K could be recommended for the production of maize. 展开更多
关键词 Agronomic efficiency balanced Fertilization Economic Optimal Rate Maize Yield Nutrient Response Function Partial Factor Productivity
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Scientific Land Reform in Nepal: Question of Equity and Efficiency
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作者 P. B. Nepali K. N. Pyakuryal S. R. Sharma 《Journal of Agricultural Science and Technology(A)》 2011年第3X期315-325,共11页
关键词 土地改革 尼泊尔 科学 权力结构 经济增长 社会关系 土地问题 通行条件
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Improving the Efficiency of the State Budget Balance in Vietnam
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作者 Hoang Anh Dao 《Macro Management & Public Policies》 2021年第2期24-32,共9页
The state budget balance is always an extremely important issue for each government.In 2020,Vietnam has a relatively small-scale economy.Its economic scale and GDP per capita reached 271.2 billion USD and 2,779 USD re... The state budget balance is always an extremely important issue for each government.In 2020,Vietnam has a relatively small-scale economy.Its economic scale and GDP per capita reached 271.2 billion USD and 2,779 USD respectively.Budget revenue is still limited,but the need for recurrent spending and development investment is still very large now and in many years to come.In the past time,budget revenue and expenditure are in a situation of not having the necessary balance,the state budget deficit has been still around 4.5 percent of GDP.The actual state budget revenue and expenditure balance have been revealing several disadvantages.Faced to such a situation,the author would like to present some important issues about the state budget revenue and expenditure and propose key solutions to increase the efficiency of state budget revenue and expenditure in Vietnam. 展开更多
关键词 State budget Revenue and expenditure balance Economic development efficiency VIETNAM
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Postponed and reduced basal nitrogen application improves nitrogen use efficiency and plant growth of winter wheat 被引量:18
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作者 TIAN Zhong-wei LIU Xiao-xue +6 位作者 GU Shi-lu YU Jin-hong ZHANG Lei ZHANG Wei-wei JIANG Dong CAO Wei-xing DAI Ting-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第12期2648-2661,共14页
Excessive nitrogen(N) fertilization with a high basal N ratio in wheat can result in lower N use efficiency(NUE) and has led to environmental problems in the Yangtze River Basin, China. However, wheat requires less N ... Excessive nitrogen(N) fertilization with a high basal N ratio in wheat can result in lower N use efficiency(NUE) and has led to environmental problems in the Yangtze River Basin, China. However, wheat requires less N fertilizer at seedling growth stage, and its basal N fertilizer utilization efficiency is relatively low; therefore, reducing the N application rate at the seedling stage and postponing the N fertilization period may be effective for reducing N application and increasing wheat yield and NUE. A 4-year field experiment was conducted with two cultivars under four N rates(240 kg N ha–1(N240), 180 kg N ha–1(N180), 150 kg N ha–1(N150), and 0 kg N ha–1(N0)) and three basal N application stages(seeding(L0), fourleaf stage(L4), and six-leaf stage(L6)) to investigate the effects of reducing the basal N application rate and postponing the basal N fertilization period on grain yield, NUE, and N balance in a soil-wheat system. There was no significant difference in grain yield between the N180 L4 and N240 L0(control) treatments, and the maximum N recovery efficiency and N agronomy efficiency were observed in the N180 L4 treatment. Grain yield and NUE were the highest in the L4 treatment. The leaf area index, flag leaf photosynthesis rate, flag leaf nitrate reductase and glutamine synthase activities, dry matter accumulation, and N uptake post-jointing under N180 L4 did not differ significantly from those under N240 L0. Reduced N application decreased the inorganic N content in the 0–60-cm soil layer, and the inorganic N content of the L6 treatment was higher than those of the L0 and L4 treatments at the same N level. Surplus N was low under the reduced N rates and delayed basal N application treatments. Therefore, postponing and reducing basal N fertilization could maintain a high yield and improve NUE by improving the photosynthetic production capacity, promoting N uptake and assimilation, and reducing surplus N in soil-wheat systems. 展开更多
关键词 basal nitrogen application stage grain yield nitrogen deficiency nitrogen use efficiency soil nitrogen balance WHEAT
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Nitrogen Use Efficiency as Affected by Phosphorus and Potassium in Long-Term Rice and Wheat Experiments 被引量:9
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作者 DUAN Ying-hua SHI Xiao-jun +2 位作者 LI Shuang-lai SUN Xi-fa HE Xin-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期588-596,共9页
Improving nitrogen use efficiency (NUE) and decreasing N loss are critical to sustainable agriculture. The objective of this research was to investigate the effect of various fertilization regimes on yield, NUE, N a... Improving nitrogen use efficiency (NUE) and decreasing N loss are critical to sustainable agriculture. The objective of this research was to investigate the effect of various fertilization regimes on yield, NUE, N agronomic efficiency (NAE) and N loss in long-term (16- or 24-yr) experiments carried out at three rice-wheat rotation sites (Chongqing, Suining and Wuchang) in subtropical China. Three treatments were examined: sole chemical N, N+phosphorus (NP), and NP+potassium (NPK) fertilizations. Grain yields at three sites were significantly increased by 9.3-81.6% (rice) and 54.5-93.8% (wheat) under NP compared with N alone, 1.7-9.8% (rice) and 0-17.6% (wheat) with NPK compared with NP. Compared to NP, NUE significantly increased for wheat at Chongqing (9.3%) and Wuchang (11.8%), but not at Suining, China. No changes in NUE were observed in rice between NP and NPK at all three sites. The rice-wheat rotation's NAE was 3.3 kg kg1 higher under NPK than under NP at Chongqing, while NAE was similar for NP and NPK at Suining and Wuchang. We estimated that an uptake increase of 1.0 kg N hal would increase 40 kg rice and 30 kg wheat ha-1. Nitrogen loss/input ratios were -60, -40 or -30% under N, NP or NPK at three sites, indicating significant decrease of N loss by P or PK additions. We attribute part of the increase in NUE soil N accumulation which significantly increased by 25-55 kg ha-1 yr1 under NPK at three sites, whereas by 35 kg ha-1 yr-1 under NP at Chongqing only. This paper illustrates that apply P and K to wheat, and reduce K application to rice is an effective nutrient management strategy for both the NUE improvement and N losses reduction in China. 展开更多
关键词 apparent nitrogen balance grain yield nitrogen agronomic efficiency nitrogen loss soil nitrogen accumulation
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Integrated application of February Orchid(Orychophragmus violaceus) as green manure with chemical fertilizer for improving grain yield and reducing nitrogen losses in spring maize system in northern China 被引量:8
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作者 BAI Jin-shun CAO Wei-dong +3 位作者 XIONG Jing ZENG Nao-hua GAO Song-juan Shimizu Katsuyoshi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2490-2499,共10页
The development of more efficient management systems is crucial to achieving high grain yields with high nitrogen use efficiency(NUE). February Orchid-spring maize rotation system is a newly established planting sys... The development of more efficient management systems is crucial to achieving high grain yields with high nitrogen use efficiency(NUE). February Orchid-spring maize rotation system is a newly established planting system with the benefits of ground cover and potential wind erosion in northern China. A field experiment was conducted to evaluate the effects of integrated application of February Orchid as green manure with reduction of chemical fertilizers(INTEGRATED) on spring maize yield, N uptake, ammonium volatilization, and soil residual mineral N in northern China. Compared to farmers' traditional fertilization(CON), integrated application of February Orchid as green manure with 30% reduction of nitrogen fertilizers(INTEGRATED) increased maize grain yield and biomass by 9.9 and 10.2%, respectively. The 0–100 cm soil residual Nmin at harvest was decreased by 58.5% and thus nitrogen use efficiency was increased significantly by 26.7%. The nitrogen balance calculation further demonstrated that the INTEGRATED approach performed better than CON with lower apparent nitrogen loss(decreased by 48.9%) which evidenced by the ammonium volatilization of top-dressing fertilizer was decreased by 31.1%, the N_(min) movement to the deeper soil layers was reduced, and the apparent nitrogen leaching loss nearly equal to 0 under the INTEGRATED treatment. Therefore, in northern China, integrated application of green manure and chemical fertilizers is an efficient management approach for improving maize yields and NUE simultaneously. 展开更多
关键词 cover crop ammonium volatilization mineral nitrogen nitrogen use efficiency nitrogen balance
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Promoting Balance in Output Efficiencies for Cross-Efficiency Evaluation in Data Envelopment Analysis
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作者 Jin-Xiao Chen 《Journal of Applied Mathematics and Physics》 2019年第3期664-685,共22页
Cross-efficiency evaluation is recognized as an effective way of efficiency assessment for a set of decision making units (DMUs) in the framework of data envelopment analysis (DEA). It has been generally suggested tha... Cross-efficiency evaluation is recognized as an effective way of efficiency assessment for a set of decision making units (DMUs) in the framework of data envelopment analysis (DEA). It has been generally suggested that secondary goals be introduced for cross-efficiency evaluation owing to the non-uniqueness of optimal solutions in self-evaluation. This paper develops a variety of secondary goals in the spirit of promoting balance in the output efficiencies of the DMU under evaluation. The proposed models attempt to make each output contribute as equally as possible to the self-evaluated efficiency. In this way, the weight flexibility can for one thing be reduced by the introduced secondary goals with selections from alternate optimal solutions, in addition to counting on the dilution of flexibility in the subsequent peer-evaluation. The proposed approach might be applicable to evaluation problems in which multiple outputs are considered important and balance is encouraged to put all dimensions into sufficient use. The effectiveness of the proposed approach and its comparisons with some relevant secondary goals are illustrated empirically using numerical examples. 展开更多
关键词 Data Envelopment Analysis Cross-efficiency Evaluation SECONDARY GOAL balance OUTPUT efficiency
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Comparison of the local pivotal method and systematic sampling for national forest inventories
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作者 Minna Räty Mikko Kuronen +3 位作者 Mari Myllymäki Annika Kangas Kai Mäkisara Juha Heikkinen 《Forest Ecosystems》 SCIE CSCD 2020年第4期716-732,共17页
Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random samp... Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random sampling(SRS)and LPM with geographical coordinates has produced promising results in simulation studies.In this simulation study we compared all these sampling methods to systematic sampling.The LPM samples were selected solely using the coordinates(LPMxy)or,in addition to that,auxiliary remote sensing-based forest variables(RS variables).We utilized field measurement data(NFI-field)and Multi-Source NFI(MS-NFI)maps as target data,and independent MS-NFI maps as auxiliary data.The designs were compared using relative efficiency(RE);a ratio of mean squared errors of the reference sampling design against the studied design.Applying a method in NFI also requires a proven estimator for the variance.Therefore,three different variance estimators were evaluated against the empirical variance of replications:1)an estimator corresponding to SRS;2)a Grafström-Schelin estimator repurposed for LPM;and 3)a Matérn estimator applied in the Finnish NFI for systematic sampling design.Results:The LPMxy was nearly comparable with the systematic design for the most target variables.The REs of the LPM designs utilizing auxiliary data compared to the systematic design varied between 0.74–1.18,according to the studied target variable.The SRS estimator for variance was expectedly the most biased and conservative estimator.Similarly,the Grafström-Schelin estimator gave overestimates in the case of LPMxy.When the RS variables were utilized as auxiliary data,the Grafström-Schelin estimates tended to underestimate the empirical variance.In systematic sampling the Matérn and Grafström-Schelin estimators performed for practical purposes equally.Conclusions:LPM optimized for a specific variable tended to be more efficient than systematic sampling,but all of the considered LPM designs were less efficient than the systematic sampling design for some target variables.The Grafström-Schelin estimator could be used as such with LPMxy or instead of the Matérn estimator in systematic sampling.Further studies of the variance estimators are needed if other auxiliary variables are to be used in LPM. 展开更多
关键词 Auxiliary data Bias Local pivotal method Matérn estimator National forest inventory Sampling efficiency Simple random sampling Spatially balanced sampling Systematic sampling Variance
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On the Maximum of Wind Power Efficiency
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作者 Gerhard Kramm Gary Sellhorst +3 位作者 Hannah K. Ross John Cooney Ralph Dlugi Nicole Mölders 《Journal of Power and Energy Engineering》 2016年第1期1-39,共39页
In our paper we demonstrate that the filtration equation used by Gorban’ et al. for determining the maximum efficiency of plane propellers of about 30 percent for free fluids plays no role in describing the flows in ... In our paper we demonstrate that the filtration equation used by Gorban’ et al. for determining the maximum efficiency of plane propellers of about 30 percent for free fluids plays no role in describing the flows in the atmospheric boundary layer (ABL) because the ABL is mainly governed by turbulent motions. We also demonstrate that the stream tube model customarily applied to derive the Rankine-Froude theorem must be corrected in the sense of Glauert to provide an appropriate value for the axial velocity at the rotor area. Including this correction leads to the Betz-Joukowsky limit, the maximum efficiency of 59.3 percent. Thus, Gorban’ et al.’s 30% value may be valid in water, but it has to be discarded for the atmosphere. We also show that Joukowsky’s constant circulation model leads to values of the maximum efficiency which are higher than the Betz-Jow-kowsky limit if the tip speed ratio is very low. Some of these values, however, have to be rejected for physical reasons. Based on Glauert’s optimum actuator disk, and the results of the blade-element analysis by Okulov and S&oslashrensen we also illustrate that the maximum efficiency of propeller-type wind turbines depends on tip-speed ratio and the number of blades. 展开更多
关键词 Wind Power Power efficiency General Momentum theory Axial Momentum theory Blade Element Analysis Betz-Joukowsky Limit Joukowsky’s Constant Circulation Model Glauert’s Optimum Actuator Disk balance Equation for Momentum Equation of Continuity balance Equation for Kinetic Energy Reynolds’ Average Hesselberg’s Average Favre’s Average Bernoulli’s Equation Integral Equations
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Energy and Material Flow Evaluation with CO2 Emissions in the Glass Production Process
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作者 Gregor Berger Zlatko Raonic +2 位作者 Daniel Forthuber Harald Raupenstrauch Robert Hermann 《Advances in Materials Physics and Chemistry》 2022年第5期82-105,共24页
Glass manufacturing is an energy-intensive process with high demands on product quality. The wide usage of glass products results in a high end-product diversity. In the past, many models have been developed... Glass manufacturing is an energy-intensive process with high demands on product quality. The wide usage of glass products results in a high end-product diversity. In the past, many models have been developed to optimize specific process steps, such as glass melting or glass forming. This approach presents a tool for the modeling of the entire glass manufacturing process for container glass, flat glass, and glass fibers. The tool considers detailed bottom-up energy and material balance in each step of the processing route with the corresponding costs and CO<sub>2</sub> emissions. Subsequently, it provides the possibility to quantify optimization scenarios in the entire glass manufacturing process in terms of energy, material and cost flow efficiency. 展开更多
关键词 Energy efficiency Glass Industry Energy balance Container Glass Flat Glass Glass Fiber
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Bubble size modeling approach for the simulation of bubble columns
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作者 Xibao Zhang Zhenghong Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期194-200,共7页
The constant bubble size modeling approach(CBSM)and variable bubble size modeling approach(VBSM)are frequently employed in Eulerian–Eulerian simulation of bubble columns.However,the accuracy of CBSM is limited while ... The constant bubble size modeling approach(CBSM)and variable bubble size modeling approach(VBSM)are frequently employed in Eulerian–Eulerian simulation of bubble columns.However,the accuracy of CBSM is limited while the computational efficiency of VBSM needs to be improved.This work aims to develop method for bubble size modeling which has high computational efficiency and accuracy in the simulation of bubble columns.The distribution of bubble sizes is represented by a series of discrete points,and the percentage of bubbles with various sizes at gas inlet is determined by the results of computational fluid dynamics(CFD)–population balance model(PBM)simulations,whereas the influence of bubble coalescence and breakup is neglected.The simulated results of a 0.15 m diameter bubble column suggest that the developed method has high computational speed and can achieve similar accuracy as CFD–PBM modeling.Furthermore,the convergence issues caused by solving population balance equations are addressed. 展开更多
关键词 Bubble column Bubble size modeling Numerical simulation Population balance equations Computational efficiency
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Improved Hybrid Swarm Intelligence for Optimizing the Energy in WSN
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作者 Ahmed Najat Ahmed JinHyung Kim +1 位作者 Yunyoung Nam Mohamed Abouhawwash 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2527-2542,共16页
In this current century,most industries are moving towards automation,where human intervention is dramatically reduced.This revolution leads to industrial revolution 4.0,which uses the Internet of Things(IoT)and wirel... In this current century,most industries are moving towards automation,where human intervention is dramatically reduced.This revolution leads to industrial revolution 4.0,which uses the Internet of Things(IoT)and wireless sensor networks(WSN).With its associated applications,this IoT device is used to compute the receivedWSN data from devices and transfer it to remote locations for assistance.In general,WSNs,the gateways are a long distance from the base station(BS)and are communicated through the gateways nearer to the BS.At the gateway,which is closer to the BS,energy drains faster because of the heavy load,which leads to energy issues around the BS.Since the sensors are battery-operated,either replacement or recharging of those sensor node batteries is not possible after it is deployed to their corresponding areas.In that situation,energy plays a vital role in sensor survival.Concerning reducing the network energy consumption and increasing the network lifetime,this paper proposed an efficient cluster head selection using Improved Social spider Optimization with a Rough Set(ISSRS)and routing path selection to reduce the network load using the Improved Grey wolf optimization(IGWO)approach.(i)Using ISSRS,the initial clusters are formed with the local nodes,and the cluster head is chosen.(ii)Load balancing through routing path selection using IGWO.The simulation results prove that the proposed optimization-based approaches efficiently reduce the energy through load balancing compared to existing systems in terms of energy efficiency,packet delivery ratio,network throughput,and packet loss percentage. 展开更多
关键词 Wireless sensor networks(WSN) internet of things(IoT) energy efficiency load balance SENSORS grey wolf optimization social spider optimization
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公交专用车道规划管理思辨及公共汽电车交通发展纾困
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作者 孔令斌 徐康明 +16 位作者 陈小鸿 关宏志 安健 潘昭宇 高胜庆 杨涛 景国胜 周涛 邵丹 刘明姝 刘迁 苏跃江 钟志新 王园园 黄伟 郑猛 刘振国 《城市交通》 2024年第1期15-28,共14页
2023年上半年,公安部推出10项公安交管新措施,其中包括优化城市公交专用车道管理。北京、深圳、青岛、南通等地陆续发布公交专用车道相关管理措施,引发广泛讨论与关注。围绕公交专用车道管理措施背后的原因与调整的依据,公交专用车道本... 2023年上半年,公安部推出10项公安交管新措施,其中包括优化城市公交专用车道管理。北京、深圳、青岛、南通等地陆续发布公交专用车道相关管理措施,引发广泛讨论与关注。围绕公交专用车道管理措施背后的原因与调整的依据,公交专用车道本身的规划、管理与使用问题,以及公共汽电车交通运营困境,特邀城市交通行业专家学者和公共汽电车运营管理研究的一线工作人员以笔谈的形式交流观点。在此基础上,探索在城市存量发展阶段如何建立常态化路权变更规则和评估机制,以及公共汽电车交通纾困之路。 展开更多
关键词 交通治理 公共汽电车 公交专用车道 公交优先 路权 公平 效率 政策
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我国五大城市群县域科技创新效率空间分异与障碍因子分析
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作者 肖松 邹小伟 +1 位作者 张永薇 姚栋夫 《科技进步与对策》 北大核心 2024年第12期35-46,共12页
城市群作为创新要素集聚地,在全国生产力布局中发挥战略性支撑作用,县域是城市群协同创新的重要空间载体,在中国未来城市发展中拥有不可或缺的重要地位。采用DEA-BCC效率模型、核密度、空间探索性等研究方法,测算2018—2021年长三角、... 城市群作为创新要素集聚地,在全国生产力布局中发挥战略性支撑作用,县域是城市群协同创新的重要空间载体,在中国未来城市发展中拥有不可或缺的重要地位。采用DEA-BCC效率模型、核密度、空间探索性等研究方法,测算2018—2021年长三角、珠三角、中原、成渝以及长江中游城市群所辖县域科技创新效率,并采用障碍度模型识别影响五大城市群县域创新效率的主要因素。结果表明:五大城市群县域科技创新效率存在较大差距,其中,高新技术产业发展、创新平台建设、企业创新投入和科技人力资源禀赋等是阻碍县域科技创新效率提升的重要因素,进而提出城市群县域科技创新效率优化路径。 展开更多
关键词 县域 城市群 创新效率 区域差异 均衡发展
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