Economic Efficiency of Maize Production in the Context of Climate Change Adaptation in the Okpara Sub-Basin

This study estimates the technical, allocative, and economic efficiency of maize-producing farms in Benin and identifies the determining factors of these efficiencies in the context of adaptation to climate change. To achieve this, data was collected from a sample of 402 corn farmers randomly selected from the municipalities most vulnerable to the effects of climate change and located within the Okpara watershed perimeters. The parametric stochastic frontier approach was adopted to estimate a seedling-log stochastic frontier and a dual cost function of corn farms using the Frontier program of Stata 13 software. The Tobit regression model was used to identify the factors determining the efficiency of producers. The results show that the operators are all technically efficient and have significant random effects. However, the results from the cost frontier show the presence of allocative inefficiency within production units. The estimated technical, allocative, and economic efficiencies are, respectively, 0.94, 0.60 and 0.57 on average. Finally, estimation of the determinants of efficiency has shown that the supply of mineral manure, experience in maize production, crop rotation as well as the level of education are the main determinants of efficiency. It is necessary to support corn producers on cultivation techniques, subsidize fertilizers, and promote literacy in the face of the effects of climate change.

Technological Progress,Structural Change and China's Energy Efficiency

China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994-2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China's declining energy intensity.

Effect of climate change on seasonal water use efficiency in subalpine Abies fabri

Abies fabri is a typical subalpine dark coniferous forest in southwestern China. Air temperature increases more at high elevation areas than that at low elevation areas in mountainous regions,and climate change ratio is also uneven in different seasons. Carbon gain and the response of water use efficiency(WUE) to annual and seasonal increases in temperature with or without CO_2 fertilization were simulated in Abies fabri using the atmospheric-vegetation interaction model(AVIM2). Four future climate scenarios(RCP2.6,RCP4.5,RCP6.0 and RCP8.5) from the Coupled Model Intercomparison Project Phase 5(CMIP5) were selectively investigated. The results showed that warmer temperatures have negative effects on gross primary production(GPP) and net primary production(NPP) in growing seasons and positive effects in dormant seasons due to the variation in the leaf area index. Warmer temperatures tend to generate lower canopy WUE and higher ecosystem WUE in Abies fabri. However,warmer temperature together with rising CO_2 concentrations significantlyincrease the GPP and NPP in both growing and dormant seasons and enhance WUE in annual and dormant seasons because of the higher leaf area index(LAI) and soil temperature. The comparison of the simulated results with and without CO_2 fertilization shows that CO_2 has the potential to partially alleviate the adverse effects of climate warming on carbon gain and WUE in subalpine coniferous forests.

Productivity Growth, Technological Progress, and Efficiency Change in Vietnamese Manufacturing Industries: A Stochastic Frontier Approach

This study applies a stochastic frontier production approach to decompose the sources of total productivity (TFP) growth into technical progress and changes in technical efficiency of 8057 firms in Vietnamese manufacturing industries during 2003-2007. Using both total manufacturing industry and sub-manufacturing industrial regressions, the analysis focuses on the trend of technological progress (TP) and technical efficiency change (TEC), and the role of productivity change in economic growth. According to the estimated results, the annual technical progress for the manufacturing industry and sub-manufacturing industries are calculated directly from the estimated parameters of the translog stochastic frontier production function by taking a partial derivative of output with respect to time t. The average technical changes in manufacturing industry and sub-manufacturing industries are positive, with an average technical change about 5.2%, 5.8%, 5.4%, 11.8%, 4.6%, 4.1%, 7.3%, 4.8%, 4.8% and 4.8% for total sample, food products & beverages, textile & wearing apparel, footwear, paper & products, industrial chemicals, rubber & plastic products, non- metallic mineral, basic & fabricated metal and other sub-industries, respectively. Total TFP in the manufacturing sector has grown at the annual rate of 0.052, although the rate of growth decreased continuously during the sample period. For the sub-industry estimates during the sample period, TFP grew fastest in the footwear sub-industry, with annual average growth rate of 11.8%, followed by the rubber & plastic products with a rate of 7.3%, and the food products & beverages with a rate of 5.8% per annum.

Dynamic change of agricultural energy efficiency and its influencing factors in China

In order to practice the concept of‘lucid waters and lush mountains are invaluable assets’and promote the green development of agriculture,it is necessary to improve the efficiency of agricultural energy utilization.Based on the panel data of 28 provinces from 1995 to 2018,this paper calculated China’s agricultural energy input from two categories of direct energy and indirect energy,and used EBM(Epsilon-based Measure)mixed distance function model to measure the energy efficiency of agriculture in China.The nuclear density function and spatial autocorrelation were used to analyze the dynamic evolution of agricultural energy efficiency,and the dynamic panel model was used to analyze the influencing factors of agricultural energy efficiency.The results showed that:①From 1995 to 2018,the total agricultural energy input had increased year by year in China,with an average annual growth rate of 2%.Energy input structure changed from indirect energy-based to direct energy-based.Agricultural energy efficiency showed an evolutionary trend of‘rising-stagnating-rising rapidly’in China.The agricultural energy efficiency was generally low in China,and there was a large space for improvement in agricultural energy efficiency.②From 1995 to 2018,the average annual growth rate of agricultural energy efficiency in the eastern,central and western regions was 2.7%,1.9%and 1.4%respectively.In 2018,the agricultural energy efficiency in the eastern,central and western regions was 0.81,0.71 and 0.59 respectively.The gap between regions was expanding rapidly,and the agricultural energy efficiency in the central and western regions needed to be improved.③From 1995 to 2018,the agricultural energy efficiency of each province was polarized and the absolute gap was widened.There was obvious improvement in agricultural energy efficiency in Guangdong,Shandong,Jiangxi,Jiangsu,Liaoning and Tianjin,while the agricultural energy efficiency of Xinjiang,Guizhou,Zhejiang,Shanghai,and Inner Mongolia deteriorated.④From 1995 to 2018,there was no global spatial correlation of China’s agricultural energy efficiency.However,local‘high-high’concentration gradually appeared in the eastern region since 2010.⑤The first lag of energy efficiency had a significant positive impact on agricultural energy efficiency,and agricultural energy efficiency improvement had a time lag.The level of human capital,per capita net income of farmers and the level of urbanizaton had a significant positive impact on agricultural energy efficiency.The disaster rate,the level of development of secondary and tertiary industries,and the level of opening up had a significant negative impact on agricultural energy efficiency.In the implementation of the strategy of rural revitalization,we should focus on the central and western regions,take the cultivation of professional farmers as the key,focus on improving agricultural production conditions,enhance the level of cooperation between regions,exert the leading role of the secondary and tertiary industries,and enhance the ability of agricultural disaster prevention and mitigation.

Organic matter transformation ratio, hydrocarbon expulsion efficiency and shale oil enrichment type in Chang 7_(3) shale of Upper Triassic Yanchang Formation in Ordos Basin, NW China

The major enrichment type of shale oil in the Chang 7_(3) shale of Upper Triassic Yanchang Formation in the Ordos Basin is unknown.This paper analyzes the organic matter transformation ratio,hydrocarbon expulsion efficiency and roof/floor sealing conditions of the Chang 7_(3) shale,and evaluates the major enrichment type of shale oil in this interval.The average organic matter transformation ratio of the Chang 7_(3) shale is about 45%;in other words,more than 50%of the organic matters have not transformed to hydrocarbons,and the lower the maturity,the greater the proportion of untransformed organic matters.The cumulative hydrocarbon expulsion efficiency of the transformed hydrocarbon is 27.5% on average,and the total proportion of untransformed organic matters plus retained hydrocarbons is greater than 70%.The relative hydrocarbon expulsion efficiency of the Chang 7_(3) shale is 60%on average,that is,about 40% of hydrocarbons retain in the shale.The Chang 7_(3) shale corresponds to Chang 7_(1+2) and Chang 8 sandstones as the roof and floor,respectively,and is further overlaid by Chang 6 shale,where extensive low porosity and low permeability–tight oil reservoirs have formed in the parts with relatively good porosity and permeability.Moreover,the Chang 7_(3) shale is tested to be in a negative pressure system(the pressure coefficient of 0.80–0.85).Therefore,the roof/floor sealing conditions of the Chang 7_(3) shale are poor.The retained hydrocarbons appear mostly in absorbed status,with low mobility.It is concluded that the medium–high mature shale oil is not the major enrichment type of shale oil in the Chang 7_(3) shale,but there may be enrichment opportunity for shale oil with good mobility in the areas where the sealing conditions are good without faults and fractures and oil reservoirs are formed off Chang 7_(1+2),Chang 6 and Chang 8.Furthermore,low–medium mature shale oil is believed to have great potential and is the major enrichment type of shale oil in the Chang 7_(3) shale.It is recommended to prepare relevant in-situ conversion technologies by pilot test and figure out the resource availability and distribution.

Inter-Basin Water Transfer Projects and Climate Change: The Role of Allocation Protocols in Economic Efficiency of the Project. Case Study: Dez to Qomrood Inter-Basin Water Transmission Project (Iran)

Nowadays, there is a growing emphasis on Inter-basin water transfer projects as costly activities with ambiguous effects on environment, society and economy. Since the concept of climate change was in its embryonic phase before 1990’s, the majority of these projects planned before that period have not considered the effect of long term variation of water resources. In all of these numerous operational and under-construction projects, an intelligent selection of the best water transmission protocol, can help the governments to optimize their expenditures on these projects ,and also can help water resources managers to face climate change effects wisely. In this paper as a case study, Dez to Qomrood inter-basin water transfer project is considered to evaluate the efficiency of three different protocols in long term. The effect of climate change has been forecasted via a wide range of GCMs (Global Circulation Model) in order to calculate the change of flow in the basin's area with different climate scenarios. After these calculation, a water allocation model has been used to evaluate which of these three water transmission protocols (Proportional Allocation (PA), Fix Upstream allocation (FU), and Fix Downstream allocation (FD)) is the most efficient logic switch economically in a framework including both upstream and downstream stakeholders. As the final result, it can be inferred that Fix Downstream allocation (FD) protocol can supply more population especially with urban water for a fix expense and also is the most adapted protocol with future global change, at least in the first round of sustainability assessment.

Calculating the Yield, Water Utilize Efficiency and Water Productivity for Carrot Crop under Climate Change Effects

The present work analyzed the yield, water utilize efficiency and water productivity for carrot Crop under climate change effects. In this research, river water was used with irrigation ratios with drain water to irrigate the carrots (Daucus carota L.) crop during the winter growing season 2021-2022 in free field and utilizing furrow irrigation method with calculation the water use efficiency and water productivity to three sites. The study was conducted in the three sites in the Babil province in Town of Sadat-AlHindya reached 80 km from Baghdad city. Site 1 was used 33% drain water and 67% river water while site 2 was used 83% drain water and 17% river water but the site 3 was used 100% river water. The reduction of yield in site 1 was 17.3% and in site 2 was 75%. The reducing of WUE in site 1 was 23% and in site 2 was 77%. The decrease of WP in site 1 was 22.98% and in site 2 was 82.28%. The value of water stress coefficient (Ks) because irrigation by water salanity and soil salanty was 0.83, 0.78 and 0.92 in site 1,site 2 and site 3, respectively, water salanity and soil salanty reduction in productivity by 9%, 14% and 7% in production of site 1, site 2 and site 3, respectively in every irrigating.

THE CURATIVE EFFECT OF HIGH EFFICIENCY HEMODIALYSIS AND THE GRADIENT CHANGE OF PLASMA OSMOTIC PRESSURE(Report of 27 Cases)

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Recognizing production options for pearl millet in Pakistan under changing climate scenarios

Climate change is making the lands a harsher environment all over the world including Pakistan. It is expected to oppose us with three main challenges： increase in temperature up to 2-5℃ （heat stress）, increasing water stress and severe malnourishment due to climate change. It has been foreseen that there will be a 10% increase of dryland areas with climate change in the world, with more variability and incidences of short periods of extreme events （drought and heat stress）. Pearl millet is a hardy, climate smart grain crop, idyllic for environments prone to drought and heat stresses. The crop continues to produce highly nutritious grain sustainably, thereby encouraging the fight against poverty and food insecurity due to its resilience. The crop is more responsive to good production options （planting time, planting density, inter/intra row spacing, nitrogen application and irrigation）. It has high crop growth rate, large leaf area index and high radiation use efficiency that confers its high potential yield. In most of the cases, pearl millet is remained our agricultural answer to the climate calamity that we are facing, because it is selected as water saving, drought tolerant and climate change complaint crop. In view of circumstances, pearl millet cultivation must be retrieved by recognizing production options in context to changing climate scenarios of Pakistan using crop modeling techniques.

Changing energy intensity in China:a decomposition analysis

This study proposed a decomposition method based on the normalized quadratic shadow unit cost function to explore the determinants of the change in energy intensity in China from 1985 to 2010.The decomposition analysis indicates that (1) the improvement in technical efficiency dramatically reduced the energy intensity,whereas technological change played only a minor role,which could be attributed to a rebound effect;(2) the aggregated allocation effect was small because the change in the allocative distortion between capital and energy significantly enhanced energy intensity but was partly offset by the effect stemming from the change in the allocative distortion between capital and energy;and (3) the substitution of energy for labor increased energy intensity,but the aggregated substitution effect significantly reduced energy intensity because the substitution of capital for energy reduced energy intensity to a great extent.These findings were obtained at the national level and varied at die regional level.

A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change

The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical example.To understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC model.Then,the gross primary productivity(GPP)and evapotranspiration(ET)were simulated.The results show that the DDS parameter calibration method has a better performance.The annual GPP and ET show an increasing trend,while the WUE shows a decreasing trend.Meanwhile,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and November.Furthermore,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario.WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario.This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau.

Energy Efficiency Improvement of an Industrial Crystallization Process Using Linearizing Control

This paper illustrates the benefits of a multivariable linearizing control approach applied to an industrial crystallization process. This relevant approach is declined according to two different strategies: first, a setpoint tracking is proposed for the couple crystal mass/concentration, whereas a second way consists in tracking of crystal content and concentration. The controlled variables, unavailable online, are issued from an observer developed in previous works. The performance of these strategies, which application to cane sugar crystallization constitutes a real novelty, are compared with experimental data issued from a PID-controlled industrial plant. The results reveal a significant improvement of energy efficiency, leading to an economy of more than 10% of energy.

Economic and Land Use Impacts of Improving Water Use Efficiency in Irrigation in South Asia

This paper modifies and uses an advanced computable general equilibrium model coupled with biophysical data on land and water resources by Agro-Ecological Zone (AEZ) at the river basin level to examine the economy-wide consequences of im-provements in water use efficiency (WUE) in irrigation in South Asia. This is the first time the benefits of such improvements have been evaluated in an economy-wide context. It shows that such improvements increase production of food items, enhance food exports, and significantly improve food security in South Asia. Improvement in water use efficiency also leads to lower food prices, provides the opportunity to extend irrigated areas, decreases demand for cropland, and enhances reforestation. Im-provement in water use efficiency in irrigation also generates important net GDP gains across the South Asia region. Investments in improved WUE of up to 40% can be economically justified in Bangladesh, India, and Sri Lanka. However, in Nepal, for an improvement of more than 20% in WUE, the economic gains are smaller than costs from the associated investments. In Pakistan and rest of South Asia, an improvement in WUE of up to 30% appears to be economically profitable.

Efficiency Improvement of PV Generation System by Using Improved P ＆ O Method of MPPT

The conventional P ＆ O （perturb-and-observe） method, which is the most widely used as MPPT （maximum power point tracking） control, has the problem of low efficiency and unstable operation when solar radiation changes drastically. Aiming at this problem, this paper improves the conventional P ＆ O method to reduce the bad effect of solar radiation by shortening the sampling interval of PV module＇s output power while keeping the operating period unchanged. Experiments are conducted to study efficiency gains of improved method when solar radiation changes drastically. The result shows that, by this method, the efficiency of MPPT control can be increased 17% in average when PV module simulator is used and 20% at maximum when actual PV module is used, compared with the conventional P ＆ O method.

Energy Efficiency of Reactive Dynamic Compensators

A parameter that allows an evaluation of power quality transmitted, or distributed, between energy source and the final user is electric system power factor. Among other aspects, a bigger power factor, close to unit value, relieves operational conditions of lines and cables, besides, it improves feeder＇s voltage behavior. Due to load variation along the day, the dynamic compensation of power factor allows maintaining this parameter close to the ideal. This paper brings a study about a reactive dynamic compensator based on the voltage control in a capacitive element, varying the reactive energy in accordance with the system demand, everything from the energy efficiency point of view. In distribution systems, the losses due to this variable compensation can be lower than in other compensation methods and also the voltage presents a better behavior, justifying its application.

裂缝性水封气藏解封特征影响因素与变化规律

裂缝性气藏水封气严重影响气井产能发挥,通过降低井底压力来降低裂缝中压力以形成较大的基质—裂缝压差是实现解封的重要手段,但影响解封过程的众多因素尚不明确。为此,开展了裂缝性水封气藏解封压差测试实验和微观排水孔隙尺度模拟,明确了不同因素对解封压差和解封效率的影响规律,建立了裂缝性水封气藏解封压差预测模型,揭示了水封气解封过程中气体微观排水特征、流体微观分布演化规律以及不同因素对气驱排水解封的作用机制。研究结果表明:(1)解封压差是评价裂缝性水封气藏解封难易程度的重要指标,储层渗透率、润湿性、气水界面张力、水封程度和裂缝压力是影响解封特征的关键因素。随着基质渗透率降低,水封段塞对气体流动的阻碍作用增强,解封压差大幅增加;同时,解封压差会随着水封程度和裂缝压力的增加而增大。(2)利用润湿反转剂可改善孔隙壁面润湿性,降低气水界面张力,且随着基质渗透率增加,润湿反转剂更容易进入基质孔隙并改善其润湿性,解封压差的降低幅度更显著;但随着润湿反转剂浓度的增加,由于表面润湿性和气水界面张力的共同作用,解封压差呈现先增加后降低的趋势。(3)解封效率是评价解封效果的重要指标,且不同因素对解封压差和解封效率的影响机理存在差异。当裂缝内压力增加时,气体微观波及效率提高,解封效率增加;随着润湿反转剂浓度的增加,解封效率呈现先降低后上升的趋势;孔隙壁面润湿性由亲水性转化为疏水性,对指进现象有明显的抑制作用,能够大幅提高解封效率;同时气水界面张力降低,对指进现象产生一定的促进作用,解封效率略微降低。结论认为,裂缝性水封气藏可通过降低井底压力和注入润湿反转剂的方法实现解封,对该类气藏的高效开发具有重要的指导意义。

大棚蔬菜采摘运输设备的研究与设计

【目的】目前大棚蔬菜采摘设备存在人工劳动强度大、效率低、使用受限等问题,因此亟需研发一款性价比高的大棚蔬菜采摘助力装备。【方法】在大量实地调研和实践的基础上,设计了一种基于单片机控制的新型大棚蔬菜采摘运输设备。该设备主要由换垄机构、张紧机构、传送机构和支撑机构四部分组成,分析了该设备的总体设计思路,并详细阐述了各机构设计及关键技术和创新点。【结果】该运输设备具有结构简单、造价低、使用方便、机械化程度高、适应性强等特点,换垄机构不仅能实现宽度可调以适应不同垄宽,而且可以通过链传动实现机械换垄,同时采用“对对门”支撑,能有效防止钢丝绳下垂,方便菜筐通过。【结论】该大棚蔬菜采摘运输设备能极大程度降低人工劳动强度,提高采摘效率,具有很好的市场前景。未来还将研发自主识别采摘设备,实现大棚蔬菜采摘的全自动化,真正实现从“多人管一棚”到“一人管多棚”的转变。

Role of renewable,non-renewable energy consumption and carbon emission in energy efficiency and productivity change:Evidence from G20 economies

The challenge of achieving sustainable economic development with a secure environmental system is a global challenge faced by both developed and developing countries.Energy Efficiency(EE)is crucial in achieving sustainable economic growth while reducing ecological impacts.This research utilizes the Slack-Based Measure Data Envelopment Analysis(SBM-DEA)and the Malmquist-Luenberger Index(MLI)method to evaluate EE and productivity changes from 1995 to 2020 across G20 countries.The study uses four different input-output bundles to gauge the impact of renewable and non-renewable energy consumption and carbon emissions on EE and productivity changes.The study results show that including renewable energy consumption improves the average EE from 0.783 to 0.8578,but energy productivity declines from 1.0064 to 0.9988.Incorporating bad output(carbon emissions)in the estimation process enhances renewable EE and productivity change,resulting in an average EE of 0.6678 and MLI of 1.0044.Technological change is identified as the primary determinant of energy productivity growth in scenarios 1 and 2,while technical efficiency determines energy productivity change in scenarios 3 and 4.The Kruskal-Wallis test reveals a significant statistical difference between the mean EE and MLI scores of G20 countries.

月桂酸-石蜡二元共晶和纳米SiO_(2)气凝胶新型建筑储能材料的研制和性能表征

以月桂酸(LA)和石蜡(PS)为原料制备了月桂酸-石蜡(LA-PS)二元共晶混合物,通过真空吸附法将二元共晶混合物吸附到纳米SiO_(2)气凝胶中形成复合相变材料月桂酸-石蜡/纳米SiO_(2)气凝胶。泄漏实验表明,纳米SiO_(2)气凝胶对LA-PS的最大吸附率为70%;傅里叶红外光谱的结果显示,LA-PS/纳米SiO_(2)气凝胶具有优异的化学相容性;DSC测试结果显示,LA-PS/纳米SiO_(2)气凝胶的相变温度为35.19℃,相变潜热为115.89J/g。此外,LA-PS/纳米SiO_(2)气凝胶的储能效率为98.99%,说明LA-PS/纳米SiO_(2)气凝胶具有良好的蓄热性能。因此,制备的复合相变材料在玻璃窗透明围护结构利用方面,具有合适的相变温度、较高的相变潜热和较好的热稳定性和耐久性,从而具有较好的应用前景。