Input-output model

投入产出模型
  • 文章类型: Journal Article
    缺水,土地污染,全球变暖是可持续或绿色农业发展面临的严峻挑战和危机,需要使用高效和环境友好的管理战略来解决。本文提出了一个适用于农业绿色全要素生产率(AGTFP)评估的综合框架,结合水-能源-食品(WEF)关系下的微观和中观视角,从内部核心因素和周边环境影响两方面产生科学合理的绿色低碳农业战略,以提高绿色农业生产的可持续性。以涟水灌区(LID)三个分区为对象,通过偏最小二乘回归(PLSR)探索内部核心因素,通过偏最小二乘结构方程模型(PLS-SEM)探索外部影响路径。结果表明,与三个子区域相比,LID中的AGTFP最小(0.818),并且处于波动状态。同时,AGTFP是在考虑不良产出的情况下计算的,更接近有形生产力。资源禀赋和技术设施将促进农业生产,理想的产出将刺激绿色生产,和不良产出会抑制绿色生产。外部影响途径被证明是主要环境->次要环境->经济方面->社会方面->AGTFP。本研究中提出的创新观点可以促进更可取的决策,并避免对人类自然系统造成意外后果。
    Water scarcity, land pollution, and global warming are serious challenges and crises facing the development of sustainable or green agriculture and need to be addressed using efficient and environmentally friendly management strategies. This paper proposed an integrated framework appropriate for agricultural green total factor productivity (AGTFP) assessment coupled with microscopic and mesoscopic perspectives under water-energy-food (WEF) nexus, which generated scientific and reasonable strategies for green and low-carbon agriculture from internal core factors and peripheral environmental impacts to improve green agricultural production sustainability. Taking the Lianshui irrigation district (LID) with three sub-areas as the object, internal core factors were explored by partial least squares regression (PLSR) and the external impact path through partial least squares structural equation modeling (PLS-SEM). Results indicated that AGTFP in LID was the smallest (0.818) compared to the three sub-areas and was in a fluctuating state. Meanwhile, AGTFP which was calculated considering undesirable outputs, was closer to tangible productivity. Resource endowments and technical facilities will promote agricultural production, desirable outputs will stimulate green production, and undesirable outputs can inhibit green production. The external influence pathway was shown to be primary environment - > secondary environment - > economic aspects - > social aspects - > AGTFP. The innovative perspectives presented in this study can facilitate preferable decisions and avoid unintended consequences for human-natural systems.
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  • 文章类型: Journal Article
    减少碳对于实现碳峰值和中和至关重要。因此,重要的是要确定哪些工业部门在这件事上有更多的责任。根据浙江投入产出表的数据,本研究运用投入产出法对浙江省2002-2017年42个工业部门的碳排放量进行测算和比较,并最终从生产者和消费者的角度确定碳减排的责任。研究结果表明,2002-2017年浙江省直接碳排放量和全过程碳排放量均呈持续上升趋势,碳排放强度呈先降低后升高的趋势。然而,2017年的碳排放强度远低于2002年。随着时间的推移,各部门碳排放的属性变化不大。特别是,高碳部门涵盖了大部分能源供应部门,低碳部门大多与第三产业相关,伪低碳部门主要存在于生产性服务业。在碳减排责任方面,部门之间的减排责任存在很大差异,电力和热力部门根据其生产承担最大责任,消费和碳减排总量。本研究结论可为进一步制定碳峰和碳中和计划提供一定的数据支持。
    Carbon reduction is imperative for achieving carbon peaking and neutrality. Accordingly, it is important to determine which industrial sectors have more responsibility in this matter. Based on data from Zhejiang\'s input-output tables, this study applies the Input-Output method to measure and compare the carbon emissions of 42 industrial sectors in Zhejiang Province from 2002 to 2017, and then assesses the carbon emission attributes of each industrial sector, and ultimately determines the responsibility for carbon emission reduction from the perspectives of the producers and consumers. The results of the study show that direct carbon emissions and whole-process carbon emissions in Zhejiang increased continuously from 2002 to 2017, with carbon emission intensity first decreasing and then increasing. However, carbon emission intensity was much lower in 2017 than in 2002. Over time, the attributes of carbon emissions by sector changed little. Particularly, high-carbon sectors covered most of the energy supply sectors, low-carbon sectors were mostly tertiary-related, and pseudo-low-carbon sectors were mainly found in the productive services sector. In terms of carbon emission reduction responsibilities, there are large differences in emission reduction responsibilities between sectors, with the electricity and heat sectors bearing the largest responsibilities based on their production, consumption and total carbon emission reductions. The conclusions of this study can provide some data support for the further development of carbon peak and carbon neutral plans.
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  • 文章类型: Journal Article
    过去与具体污染物核算相关的研究报告说,自由贸易增加了发展中经济体的环境污染,因为发达国家“外包”他们的污染物给发展中国家。新冠肺炎疫情刺激了二战后最严重的保护主义抬头。本研究旨在探讨保护主义是否改善发展中国家的环境,集成了多区域输入输出(MRIO),数据包络分析(DEA),和情景分析。我们从两个角度揭示了保护主义的作用:对污染物排放的单一影响和对环境效率的综合影响。具体来说,资本投入,劳动投入,能源消耗,经济产出,二氧化碳,基于MRIO模拟了与全球贸易活动相关的二氧化硫和氮氧化物排放。然后,部门级贸易环境效率是通过使用非径向方向距离函数对MRIO和DEA进行分级来计算的。最后,估计了发展中国家和发达国家在有贸易和没有贸易的两种情况下的环境效率。结果证实,贸易使发展中经济体的CO2,SO2和NOX排放量增加了12.9%,9.8%和12.3%,使发达经济体下降了6.0%,29.4%和21.2%,分别。然而,结果还发现,发展中经济体和发达经济体的环境效率下降了3%和5%,分别,在无贸易情况下。我们认为,保护主义不利于发展中国家的可持续发展,因为它降低了它们的环境效率,尽管这可能会减少他们的领土污染物排放。对于发达国家来说,保护主义对污染物减排的单一影响和对环境效率的综合影响都是负面的。
    Past studies related to embodied pollutant accounting reported that free trade has increased the environmental pollution of developing economies, because the developed countries \"outsource\" their pollutants to developing nations. The COVID-19 pandemic has stimulated the rise of the most serious protectionism after World War II. This study is aimed to discuss whether protectionism improve the environment in developing countries by developing a comprehensive evaluation model, which integrates multi-regional input-output (MRIO), data envelopment analysis (DEA), and scenario analysis. We revealed the role of protectionism from two perspectives: the single impact on pollutant emissions and the comprehensive impact on environmental efficiency. Specifically, the capital inputs, labor inputs, energy consumption, economic output, carbon dioxide, sulfur dioxide and nitrogen oxides emissions related to global trade activities were simulated based on the MRIO. And then, sector-level trade environmental efficiency was computed by intergrading the MRIO and DEA using a non-radial directional distance function. Finally, the environmental efficiency of both developing and developed countries under two scenarios with and without trade were estimated. The results confirmed that trade has increased the CO2, SO2 and NOX emissions of developing economies by 12.9%, 9.8% and 12.3%, and has reduced that of developed economies by 6.0%, 29.4% and 21.2%, respectively. However, the results also uncovered that the environmental efficiency of developing and developed economies was dropped by 3% and 5%, respectively, under no-trade scenario. We contend that protectionism is not conducive to the sustainable development of developing countries because it lowers their environmental efficiency, although it may reduce their territorial pollutant emissions. For developed countries, the single impact of protectionism on pollutant emission reduction and the comprehensive impact on environmental efficiency are both negative.
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  • 文章类型: Journal Article
    随着世界经济体系内的分工日益复杂,令人不安的事件对经济系统的影响正在扩大。最近,日本提议向太平洋排放核废水,这将对海洋渔业造成损害,从而严重影响日本和世界其他国家和地区的渔业和其他产业。考虑到最终和中间需求转移的不同情况,本文利用不可运行性投入产出模型(IIM)和多区域投入产出模型(MRIO)模拟了日本核废水排放的经济后果,并计算了各行业和国家(地区)的经济变化。结果表明:短期内,只有对日本渔业产品的最终需求减少。(1)经济损失较大的十个国家(地区)是日本,美国,中华台北,加拿大,智利,南非,墨西哥,秘鲁,联合王国,和爱尔兰。(2)由于需求转移导致总产出显著增长的十个国家(地区)是中国(中华人民共和国),世界的其他地方,印度,印度尼西亚,越南,菲律宾,巴西,缅甸,俄罗斯联邦,和马来西亚。(3)不同行业总产出变动的排序。从长远来看,当对日本渔业产品的中间和最终需求都减少时。(4)日本增加值的变化。(5)全球67个国家(地区)增加值的变化。增加值增幅最大的十个国家(地区)是俄罗斯联邦,中国(中华人民共和国),世界的其他地方,美国,印度尼西亚,澳大利亚,挪威,韩国,越南,和缅甸。增加值下降幅度最大的十个国家(地区)是日本,中华台北,智利,南非,秘鲁,泰国,墨西哥,柬埔寨,哥斯达黎加,摩洛哥。全球45个工业部门增加值的变化。
    As the division of work within the world economic system becomes increasingly complex, the impact of disturbing events on the economic system is expanding. Recently, Japan proposed to discharge nuclear wastewater into the Pacific Ocean, which will cause damage to marine fisheries, thereby seriously affecting fisheries and other industries in Japan and other countries and regions around the world. Considering different scenarios of final and intermediate demand shifting, this paper uses the Inoperability Input-Output Model (IIM) and Multi-Region Input-Output Model (MRIO) to simulate the economic consequences of nuclear wastewater discharge in Japan and calculate the economic changes of each industry and country (region). The results show that: In the short term, when only the final demand for Japanese fishery products decreases. (1) The ten countries (regions) with significant economic losses are Japan, the United States, Chinese Taipei, Canada, Chile, South Africa, Mexico, Peru, the United Kingdom, and Ireland. (2) The ten countries (regions) with a significant increase in total output due to demand shift are China (People\'s Republic of), the Rest of the World, India, Indonesia, Viet Nam, the Philippines, Brazil, Myanmar, the Russian Federation, and Malaysia. (3) A ranking of changes in the total output of different industries. In the long term, when both intermediate and final demand for Japanese fishery products decrease. (4) The change in value added in Japan. (5) The change in value added of 67 countries (regions) worldwide. The ten countries (regions) with the most significant increase in value-added are the Russian Federation, China (People\'s Republic of), the Rest of the World, the United States, Indonesia, Australia, Norway, Korea, Viet Nam, and Myanmar. The ten countries (regions) with the most significant decrease in value-added are Japan, Chinese Taipei, Chile, South Africa, Peru, Thailand, Mexico, Cambodia, Costa Rica, and Morocco. Changes in value added of 45 industrial sectors worldwide.
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  • 文章类型: Journal Article
    COVID-19大流行引起的健康和经济危机凸显了对国家和行业层面缓解政策进行更深入理解和调查的必要性。虽然不同的控制策略在早期阶段,比如封锁、学校和企业关闭,帮助减少了感染的数量,这些策略对企业产生了不利的经济影响,并对社会正义产生了一些有争议的影响。因此,关闭和重新开放策略的最佳时机和规模是必需的,以防止大流行的不同浪潮和控制策略的负面社会经济影响。本文提出了一种新颖的多目标混合整数线性规划公式,这导致了每个州和行业关闭和重新开放的最佳时机。正在追求的三个目标包括:(i)大流行在受感染人口中所占百分比方面的流行病学影响;(ii)基于社区对感染的脆弱性的大流行政策的社会脆弱性指数,以及失去工作;(iii)基于每个州工业不可操作性的大流行对经济的影响。所提出的模型是在包括50个状态的数据集上实现的,哥伦比亚特区,和美国的19个行业。帕累托最优解表明,对于任何控制决策(州和行业关闭或重新开放),经济影响和流行病学影响的变化方向相反。
    The health and economic crisis caused by the COVID-19 pandemic highlights the necessity for a deeper understanding and investigation of state- and industry-level mitigation policies. While different control strategies in the early stages, such as lockdowns and school and business closures, have helped decrease the number of infections, these strategies have had an adverse economic impact on businesses and some controversial impacts on social justice. Therefore, optimal timing and scale of closure and reopening strategies are required to prevent both different waves of the pandemic and the negative socioeconomic impact of control strategies. This article proposes a novel multiobjective mixed-integer linear programming formulation, which results in the optimal timing of closure and reopening of states and industries in each. The three objectives being pursued include: (i) the epidemiological impact of the pandemic in terms of the percentage of the infected population; (ii) the social vulnerability index of the pandemic policy based on the vulnerability of communities to getting infected, and for losing their job; and (iii) the economic impact of the pandemic based on the inoperability of industries in each state. The proposed model is implemented on a dataset that includes 50 states, the District of Columbia, and 19 industries in the United States. The Pareto-optimal solutions suggest that for any control decision (state and industry closure or reopening), the economic impact and the epidemiological impact change in the opposite direction.
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  • 文章类型: Journal Article
    中国正在把京津冀协同发展作为国家战略项目来推进,但是,水资源短缺和水质问题将成为制约高质量发展的瓶颈。本研究旨在探索一条可行的产业协同优化路径,实现经济增长与水环境改善的协同发展。结合改善环境效率和再生水利用的激励措施。研究方法集成了投入产出建模,系统动力学,多目标规划构建复杂多区域模型。采用动态模拟措施模拟了2020年至2030年在水资源环境约束下混合使用的不同方法的经济和环境影响。根据仿真结果,整个地区的年经济增长率可以超过6.1%,水污染物排放强度下降60.0%以上。此外,实现跨区域协同的传统制造业仍然可以释放区位优势,而不会对环境造成负面影响。此外,区域协同发展优化水资源配置,缓解水资源紧张。此外,河北省源头控制的污染物减排效果优于其他城市。最后,再生水,作为最终的治疗措施,从长远来看,对改善经济和环境改善之间的权衡具有最大的边际效应。本研究为多区域产业协同发展和资源优化配置提供了新的思路,有助于流域高质量发展。
    China is promoting the coordinated development of the Beijing-Tianjin-Hebei region as a national strategy project; however, water scarcity and water quality problems will become a bottleneck restricting high-quality development. This study aimed to explore a feasible industrial synergy optimisation pathway to realise the collaborative development of economic growth and water environment improvement, combined with incentives for environmental efficiency improvement and reclaimed water utilisation. Research methods integrate input-output modelling, system dynamics, and multi-objective programming to construct a complex multi-region model. A dynamic simulation measure was adopted to simulate the economic and environmental impacts of different approaches that mix from 2020 to 2030 under water resource environment constraints. According to the simulation results, the annual economic growth rate of the entire region can exceed 6.1%, and the emission intensities of water pollutants decrease by more than 60.0%. In addition, traditional manufacturing industries that achieve cross-regional synergy can still release location advantages without negative environmental impacts. Furthermore, regional collaborative development optimises the allocation of water resources and alleviates water stress. Moreover, the pollutant emission reduction effect of source control in Hebei was more effective than in other cities. Finally, reclaimed water, as the end treatment measure, has the largest marginal effect on improving the trade-off between economic and environmental improvement in the long run. This study provides a new approach for multi-regional industrial synergy development and optimal allocation of resources and contributes to the high-quality development of the watershed.
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  • 文章类型: Journal Article
    分析影响我国生产用水量空间差异的因素,是有效实施最严格水资源管理制度的需要。基于31个省份的投入产出表和2017年各省份按部门划分的用水量数据,构建了31个省份的用水量-经济投入产出表。采用空间结构分解分析方法分析了技术水平的影响,经济规模,生产用水空间差异的区域特征。然后将最终需求效应分解为最终需求部门结构效应,最终需求分配结构效应,人口规模效应,和消费水平效应。结果表明,生产用水量取决于经济规模和区域特征。新疆,江苏,广东,黑龙江,中部地区大多数省份的生产用水超过平均水平,而京津地区和西北地区大部分地区的使用量低于平均水平。分解结果表明,技术效应和最终需求效应是空间差异的主要因素。人口规模和消费水平的影响对最终需求效应的贡献最大。
    Analyzing the factors that affect the spatial differences in production water consumption in China is necessary to implement its most stringent water resource management system effectively. Based on the input-output tables of 31 provinces and the water-consumption data of provinces by sectors in 2017, the water consumption-economy input-output tables of 31 provinces are constructed. The spatial structural decomposition analysis method is used to analyze the impact of technology level, economic scale, and regional characteristics on spatial differences in production water consumption. The final demand effect is then decomposed into final demand sectoral structural effect, final demand distribution structure effect, population-scale effect, and consumption-level effect. The results show that production water consumption depends on the economic scale and regional characteristics. Xinjiang, Jiangsu, Guangdong, Heilongjiang, and most provinces in the central region use more production water than the average level, while those in the Beijing-Tianjin region and most in the North-west region use less than average. The decomposition results show that the technical and the final demand effects are the main factors for the spatial differences. The impact of population-scale and consumption-level contribute the most to the final demand effect.
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  • 文章类型: Journal Article
    环境足迹会计依赖于经济投入产出(IO)模型。然而,IO模型的编译既昂贵又耗时,导致缺乏及时详细的IO数据。RAS方法传统上用于预测未来的IO表,但对不可靠的估计感到怀疑。在这里,我们开发了一种机器学习增强方法,以美国摘要级表格作为演示,以提高IO表预测的准确性。该模型是通过将RAS方法与深度神经网络(DNN)模型相结合来构建的,其中RAS方法提供了基线预测,DNN模型对RAS往往性能较差的区域进行了进一步改进。我们的结果表明,DNN模型可以显着提高IO表中那些区域的性能,用于短期预测(一年),其中RAS单独具有较差的性能,R2从0.6412提高到0.8726,APE中位数从37.49%下降到11.35%。对于长期预测(5年),当R2从0.5271提高到0.7893,并且中值平均百分比误差从51.12%降低到18.26%时,改善更加显著。我们基于估计IO表评估美国碳足迹账户的案例研究也证明了该模型的适用性。我们的方法可以帮助生成及时的IO表,为各种环境足迹分析提供基础数据。
    Environmental footprint accounting relies on economic input-output (IO) models. However, the compilation of IO models is costly and time-consuming, leading to the lack of timely detailed IO data. The RAS method is traditionally used to predict future IO tables but suffers from doubts for unreliable estimations. Here we develop a machine learning-augmented method to improve the accuracy of the prediction of IO tables using the US summary-level tables as a demonstration. The model is constructed by combining the RAS method with a deep neural network (DNN) model in which the RAS method provides a baseline prediction and the DNN model makes further improvements on the areas where RAS tended to have poor performance. Our results show that the DNN model can significantly improve the performance on those areas in IO tables for short-term prediction (one year) where RAS alone has poor performance, R2 improved from 0.6412 to 0.8726, and median APE decreased from 37.49% to 11.35%. For long-term prediction (5 years), the improvements are even more significant where the R2 is improved from 0.5271 to 0.7893 and median average percentage error is decreased from 51.12% to 18.26%. Our case study on evaluating the US carbon footprint accounts based on the estimated IO table also demonstrates the applicability of the model. Our method can help generate timely IO tables to provide fundamental data for a variety of environmental footprint analyses.
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  • 文章类型: Journal Article
    在当前贸易保护主义抬头的背景下,深入了解COVID-19对经济和能源的影响,对于中国在不确定环境下应对外部冲击,增强经济韧性具有重要的现实意义。通过构建包括COVID-19冲击在内的综合经济和能源投入产出模型,本文评估了在贸易保护主义背景下COVID-19对中国宏观经济和能源消费的影响。结果如下所示。首先,在保护主义的背景下,COVID-19在中国的爆发将导致中国GDP下降2.2-3.09%,能源消耗下降1.56-2.48%,而COVID-19全球传播带来的不利溢出效应将使其国内生产总值减少2.27-3.28%,能源消耗减少2.48-3.49%。第二,国内疫情对中国建筑业的负面影响,非金属矿物产品,服务业平均比其他行业高1.29%,而COVID-19的全球传播对纺织品和服装等出口导向型行业的影响将平均比其他行业高1.23%。第三,两波大流行对中国化石能源消费的影响平均比非化石能源消费高1.44%和0.93%,分别。
    In the current context of rising trade protectionism, deeply understanding the impacts of COVID-19 on economy and energy has important practical significance for China to cope with external shocks in an uncertain environment and enhance economic resilience. By constructing an integrated economic and energy input-output model including the COVID-19 shock, this paper assesses the impacts of COVID-19 on China\'s macro-economy and energy consumption in the context of trade protectionism. The results are shown as follows. First, in the context of protectionism, the outbreak of COVID-19 in China would cause a 2.2-3.09% drop in China\'s GDP and a 1.56-2.48% drop in energy consumption, while adverse spillovers from global spread of COVID-19 would reduce its GDP by 2.27-3.28% and energy consumption by 2.48-3.49%. Second, the negative impacts of domestic outbreak on China\'s construction, non-metallic mineral products, and services would be on average 1.29% higher than those on other industries, while the impacts of global spread of COVID-19 on export-oriented industries such as textiles and wearing apparel would be on average 1.23% higher than other industries. Third, the effects of two wave of the pandemic on China\'s fossil energy consumption would be on average 1.44% and 0.93% higher than non-fossil energy consumption, respectively.
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  • 文章类型: Journal Article
    珠江三角洲(PRD)地区的环境污染在很大程度上是由该地区以外的社会经济力量驱动的,因为该地区生产的绝大多数制造产品都运往国内和国际市场。鉴于珠江三角洲在过去几十年的经济转型显著,这项研究调查了当地的影响,省,国家,1987年至2017年经济转型升级背景下,全球社会经济驱动因素对珠三角污染动态的影响。结果表明,经济转型深刻地影响了污染格局的变化。由于国际出口的快速增长,2007年之前,珠三角地区由国际出口驱动的排放份额显着增加。自2007-2008年全球金融危机以来,经济增长向国内消费驱动型模式的转变,导致地方需求和与中国其他地区的贸易对珠三角环境污染的贡献份额不断增加。同样,随着最终需求结构向高附加值的制造业和服务业发展,低附加值制造业(LVM)需求驱动的排放份额下降幅度扩大,而由高附加值制造业(HVM)需求和服务需求推动的趋势则相反。结构分解分析表明,降低排放强度仍然是减轻污染的最有效方法。由于全球金融危机以来工业部门的重大技术进步,生产投入结构变化的贡献也从2007年之前的强大推动力转变为后来的缓解力。随着降低排放强度的边际成本变得过于昂贵,生产结构和消费模式的优化可能在未来的减排中发挥更重要的作用。
    Environmental pollution in the Pearl River Delta (PRD) region is largely driven by socioeconomic forces outside the region as vast majority of manufacturing products produced in the region are destined to national and international markets. Given the remarkable economic transformation of the PRD in the past decades, this study investigates the impacts of local, provincial, national, and global socio-economic drivers on PRD\'s pollution dynamics under the background of significant economic restructuring and upgrading from 1987 to 2017. The results indicate that changes in pollution pattern were deeply shaped by the economic transformation. The share of PRD\'s emissions driven by international exports expanded significantly before 2007 as a result of the fast growth of international exports. The transformation of economic growth to domestic consumption driven model since the 2007-2008 global financial crisis had resulted in an increasing contribution share to the PRD\'s environmental pollution from local demand and trade with Rest of China (RoC). Similarly, as final demand structure evolving towards the high value-added manufacturing and services, the share of emissions driven by low value-added manufacturing (LVM) demand had decreased by an enlarged margin, while that driven by high value-added manufacturing (HVM) demand and services demand had moved in the opposite direction. The structural decomposition analysis shows that reduction in emission intensity remains the most effective way in pollution alleviation. The contribution of changes in production input structure also shifted from a strong impetus force before 2007 to a mitigating force afterwards due to significant technological progresses in the industrial sectors since the global financial crisis. With the marginal cost of reducing emission intensity becoming prohibitively expensive, the optimization of production structure and consumption pattern is likely to play more important role in future emission mitigation.
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