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Electricity Carbon Quota Trading Scheme based on Certificateless Signature and Blockchain
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作者 Xiaodong Yang Runze Diao +2 位作者 Tao Liu Haoqi Wen Caifen Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1695-1712,共18页
The carbon tradingmarket can promote“carbon peaking”and“carbon neutrality”at low cost,but carbon emission quotas face attacks such as data forgery,tampering,counterfeiting,and replay in the electricity trading mar... The carbon tradingmarket can promote“carbon peaking”and“carbon neutrality”at low cost,but carbon emission quotas face attacks such as data forgery,tampering,counterfeiting,and replay in the electricity trading market.Certificateless signatures are a new cryptographic technology that can address traditional cryptography’s general essential certificate requirements and avoid the problem of crucial escrowbased on identity cryptography.However,most certificateless signatures still suffer fromvarious security flaws.We present a secure and efficient certificateless signing scheme by examining the security of existing certificateless signature schemes.To ensure the integrity and verifiability of electricity carbon quota trading,we propose an electricity carbon quota trading scheme based on a certificateless signature and blockchain.Our scheme utilizes certificateless signatures to ensure the validity and nonrepudiation of transactions and adopts blockchain technology to achieve immutability and traceability in electricity carbon quota transactions.In addition,validating electricity carbon quota transactions does not require time-consuming bilinear pairing operations.The results of the analysis indicate that our scheme meets existential unforgeability under adaptive selective message attacks,offers conditional identity privacy protection,resists replay attacks,and demonstrates high computing and communication performance. 展开更多
关键词 Electricity carbon trading certificateless signature blockchain forgery attack carbon quota
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Different Deficit Irrigation Lower Limits and Irrigation Quotas Affect the Yield and Water Use Efficiency of Winter Wheat by Regulating Photosynthetic Characteristics
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作者 Huiqin Li Mingzhi Zhang +1 位作者 Na Xiao Haijian Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第12期3211-3236,共26页
To determine suitable thresholds for deficit irrigation of winter wheat in the well-irrigated area of the Huang-Huai-Hai Plain,we investigated the effects of different deficit irrigation lower limits and quotas on the... To determine suitable thresholds for deficit irrigation of winter wheat in the well-irrigated area of the Huang-Huai-Hai Plain,we investigated the effects of different deficit irrigation lower limits and quotas on the photosynthetic characteristics and grain yield of winter wheat.Four irrigation lower limits were set for initiating irrigation(i.e.,light drought(LD,50%,55%,60%and 50%of field holding capacity(FC)at the seedling-regreening,jointing,heading and filling-ripening stages,respectively),medium drought(MD,40%,50%,55%and 45%of FC at the same stages,respectively),adequate moisture(CK1,60%,65%,70%and 60%of FC at the same stages,respectively),heavy drought(CK2,35%,40%,45%and 40%of FC at the same stages,respectively))and five irrigation quota per event(30,60,90,120 and 180 mm)were set for each lower limit.We found that the increase of drought stress is conducive to normal photosynthesis of winter wheat leaves which is supported by the following findings.First,photosynthetic rate(Pn)of LD60 treatment was higher than that of LD30,LD90,LD120,LD180,MD30,MD60,MD90,MD120 and MD180.Then,Under the 90 mm irrigation quota treatment,the yield of winter wheat basically increased with the increase of irrigation’s lower limit.Moreover,With the increase in irrigation quota,the yield of winter wheat increased,and the water use efficiency(WUE)of winter wheat increased at first and then decreased.In addition,compared with the LD30,MD30,MD60,MD90,MD120,and MD180,the yield of winter wheat in LD60 treatment increased by about 3.23%(3-year average),32.3%,19.9%,11.7%,10.1%,and 14.6%.At the same time,the WUE with LD60 treatment of winter wheat was significantly higher than LD90,LD120,LD180,MD30,MD60,MD90,MD120,MD180 treatments.There was a positive correlation between soil volumetric water content and Pn and between yield and Pn.The key period for yield formation in winter wheat is 180 days after sowing.In conclusion,to achieve the dual goals of stable winter wheat yield and efficient utilization of water resources in this region,the suitable threshold for initiating deficit irrigation of winter wheat is the LD60 treatment.This conclusion provides data support for water-saving and stable yield of winter wheat in this area. 展开更多
关键词 Irrigation lower limit irrigation quota soil volume moisture content photosynthetic rate YIELD regression analysis
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利用quota在RHEL6系统中实现磁盘配额管理 被引量:1
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作者 曲广平 郭迎娣 《潍坊学院学报》 2013年第4期26-30,共5页
利用Linux系统中提供的quota磁盘配额功能,管理员可以对系统中的每个用户或组所能使用的磁盘空间进行配额限制,取消他们在系统上无限制地使用磁盘空间的能力。
关键词 quota 磁盘配额 RHEL6系统
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基于Linux系统利用Quota功能实现FTP中用户的磁盘配额
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作者 邵鹏 张亭亭 《科教文汇》 2012年第15期77-78,共2页
随着现代教育技术的飞速发展和教学改革的需要,FTP服务的使用以其方便、快捷、安全地把文件从远程计算机上拷到本地计算机,或把本地计算机的文件送到远程计算机去这一技术特点受到越来越多的使用,为无纸化的办公自动化系统建立了一个良... 随着现代教育技术的飞速发展和教学改革的需要,FTP服务的使用以其方便、快捷、安全地把文件从远程计算机上拷到本地计算机,或把本地计算机的文件送到远程计算机去这一技术特点受到越来越多的使用,为无纸化的办公自动化系统建立了一个良好的基础。但如何更好地使用与维护成了FTP服务器管理员的难题。 展开更多
关键词 LINUX FTP quota
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Wildlife Export Quota and Its Administrative System
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作者 孟宪林 马建章 +3 位作者 陈化鹏 常弘 高二虎 温战强 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第2期95-101,共7页
The authors discussed the administrative system of export quota and its method of calculation in the international wildlife trade. Three methods for determining wildlife export quota in China was put forvvard, based o... The authors discussed the administrative system of export quota and its method of calculation in the international wildlife trade. Three methods for determining wildlife export quota in China was put forvvard, based on the trend and status, domestic use, and historical export of wildlife resources. They include the single factor method, the double factor method, and the multiple faCtor method. In addition, the approaches and measures to establish and carry out the administrative system of wildlife export quota in China were discussed in this paper. 展开更多
关键词 EXPORT quota INTERNATIONAL WILDLIFE TRADE ADMINISTRATIVE system of WILDLIFE EXPORT
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Efficient allocation of coal de-capacity quota among Chinese provinces:a zero-sum gains data envelopment model
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作者 Gang Ma Xu Li Jianping Zheng 《Chinese Journal of Population,Resources and Environment》 2019年第3期229-240,共12页
An efficient coal de-capacity quota allocation scheme is key for accelerating China's coal supplyside structure reform.This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the... An efficient coal de-capacity quota allocation scheme is key for accelerating China's coal supplyside structure reform.This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the optimal capacity allocation in each Chinese province.First,we estimate the coal capacity of 24 coal-producing provinces based on boundary production function model.According to the actual coal overcapacity in each province,we initially allocate the coal decapacity quota of reducing 0.8 billion tons among them.Then,we optimize the initial allocation plan by using the zero-sum gains data envelopment model(ZSG-DEA)considering backward coal capacity,coal economic output,and coal resource endowment of each province.The results indicate that:First,there is coal overcapacity all over China,and there are obvious differences among the provinces.Second,the optimal allocation results show that the large coal producing provinces,including Shanxi,Inter Mongolia,Shaanxi,etc.,need to undertake most of the coal decapacity tasks,while the old coal producing provinces in northeast and west China should undertake a heavier burden of coal de-capacity.Third,the“one-size fits-all”approach burdens the small coal producing provinces with reducing coal capacity,leading to a general low enthusiasm for coal de-capacity in these regions. 展开更多
关键词 Coal de-capacity ZSG-DEA model Chinese provinces quota allocation
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China Mulls Easing QFII Quota Management
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《China's Foreign Trade》 2019年第3期4-5,共2页
China’s forex regulator said recently that the country will properly ease and even cancel quota management for Qualified Foreign Institutional Investors(QFII)in a bid to further widen the investment scope for oversea... China’s forex regulator said recently that the country will properly ease and even cancel quota management for Qualified Foreign Institutional Investors(QFII)in a bid to further widen the investment scope for overseas investors. 展开更多
关键词 China Mulls Easing QFII quota MANAGEMENT
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Random Route and Quota Sampling: Do They Offer Any Advantage over Probably Sampling Methods?
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作者 Vidal Díaz de Rada Valentín Martínez Martín 《Open Journal of Statistics》 2014年第5期391-401,共11页
The aim of this paper is to compare sample quality across two probability samples and one that uses probabilistic cluster sampling combined with random route and quota sampling within the selected clusters in order to... The aim of this paper is to compare sample quality across two probability samples and one that uses probabilistic cluster sampling combined with random route and quota sampling within the selected clusters in order to define the ultimate survey units. All of them use the face-to-face interview as the survey procedure. The hypothesis to be tested is that it is possible to achieve the same degree of representativeness using a combination of random route sampling and quota sampling (with substitution) as it can be achieved by means of household sampling (without substitution) based on the municipal register of inhabitants. We have found such marked differences in the age and gender distribution of the probability sampling, where the deviations exceed 6%. A different picture emerges when it comes to comparing the employment variables, where the quota sampling overestimates the economic activity rate (2.5%) and the unemployment rate (8%) and underestimates the employment rate (3.46%). 展开更多
关键词 Sampling Methods RANDOM Sampling MULTISTAGE Cluster Sampling RANDOM ROUTE Method quota Sampling
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Application and Analysis of Quota Design in EPC General Contract Project
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作者 SONG Guangxin 《Journal of Landscape Research》 2022年第6期29-32,共4页
EPC general contract project includes design, procurement, construction and other links. The quota design in the design link is the first procedure of EPC general contract project. It is a major measure of cost contro... EPC general contract project includes design, procurement, construction and other links. The quota design in the design link is the first procedure of EPC general contract project. It is a major measure of cost control in the design stage, and also the key to control investment and determine the success or failure of the whole project, playing a crucial role in the whole project. By analyzing the role of quota design in EPC general contract project and related control means and determining the target value from the quota design, the design is constantly improved and optimized in each stage to avoid investment risks and misunderstandings, and the effectiveness of quota design in the whole EPC general contract project is effectively improved to increase its internal application value and comprehensively improve the level of project investment control and management, thereby consolidating the core competitiveness of EPC general contract project in the whole market competition. 展开更多
关键词 EPC general contract quota design MANAGEMENT Investment control
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Multi-agent-based Approach for Determination of Time-quota in Integrated Environment
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作者 LI Shu-juan, LI Yan, ZHENG Jian-ming, XIAO Ji-ming, HONG Wei (The Mechanical and Instrument Engineering School, Xi’an University of Technology, Xi’an 710048, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期156-157,共2页
Time-quota is one of important factors in producti on system. It is affected by various factors. time-quota is studied in CAPP and p roduction schedule integration environment in this paper. An agent-based time- quota... Time-quota is one of important factors in producti on system. It is affected by various factors. time-quota is studied in CAPP and p roduction schedule integration environment in this paper. An agent-based time- quota method is put forward and the structure model is established by means of i ntelligent agent in integrated environment. The method can map the influencing t ime-quota factors into part agent related to process state and machine method a gent, resorting to the function of agent rule-based reasoning, the agents can t ransform these factors into data mode that artificial neural network (ANN) can a ccept and recognize. As a tool, ANN agent can calculate time-quota quickly. A b lackboard method is used as the means of communication and collaborative control between agents. The experiments show that precise process time-quota can be obtained rapidly with proper samples selected, continuous self-study and self -organization in system, and multi-agent approach is an effective method for d etermination of time-quota. 展开更多
关键词 MULTI-AGENT artificial neural network (ANN) ti me-quota integrated environment
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Export Quotas on Bidding for Equal Competition
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作者 Li Weicheng 《China's Foreign Trade》 1994年第10期28-28,共1页
The Trial Methods of Export Quotas on Bidding was promulgated by the Ministry of Foreign Trade and Economic Cooperation in February 1994. It is an important step in deepening reform of the foreign trade system. The Mi... The Trial Methods of Export Quotas on Bidding was promulgated by the Ministry of Foreign Trade and Economic Cooperation in February 1994. It is an important step in deepening reform of the foreign trade system. The Ministry of Foreign Trade and Economic Cooperation is responsible for supervision and instruction over the commodities 展开更多
关键词 Export quotas on Bidding for Equal Competition OVER
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Overall Planning of Public Power and Expression of Private Rights in Cross-regional Trading of Construction Land Quotas
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作者 Hong Yun 《Contemporary Social Sciences》 2021年第3期45-56,共12页
In China, the trading of construction land quotas has undergone an institutional evolution process characterized by gradual deregulation.In 2021, the Central Committee of the Communist Party of China(CPC) resolved to ... In China, the trading of construction land quotas has undergone an institutional evolution process characterized by gradual deregulation.In 2021, the Central Committee of the Communist Party of China(CPC) resolved to develop a national cross-regional trading mechanism for construction land quotas.Construction land quotas, which have attributes of both public power and private rights, share certain common grounds with the rights of land development, dumping and carbon emission.To build a national trading market for construction land quotas, it is necessary to make clarifications and innovations in macro-level ideas, meso-level mechanisms, and micro-level designs. 展开更多
关键词 construction land quotas overall planning of public power expression of private rights
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China released 2017 first batch of rare earth mining quotas
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《China Rare Earth Information》 2017年第5期1-1,共1页
China's Ministry of Land and Resources released the first batch of rare earth mining quotas in 2017, according to an announcement on the ministry's website. The total mining amount for the first batch is 52,50... China's Ministry of Land and Resources released the first batch of rare earth mining quotas in 2017, according to an announcement on the ministry's website. The total mining amount for the first batch is 52,500 tonnes, equal to the number in 2016. Out of the 52,500 tonnes, there are 43,550 tonnes for light rare earths and 8,950 tonnes for medium and heavy rare earths. 展开更多
关键词 China's MINISTRY of Land and Resources RELEASED the FIRST BATCH of rare earth MINING quotas in 2017
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MIIT issued 2017 the first batch of rare earth production control quotas
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《China Rare Earth Information》 2017年第4期4-4,共1页
MIIT issued the notice about 2017 the first batch of rare earth production control quotas recently. According to the notice, overall rare earth mineral production quantity is controlled at 52,500 tons and smelting &am... MIIT issued the notice about 2017 the first batch of rare earth production control quotas recently. According to the notice, overall rare earth mineral production quantity is controlled at 52,500 tons and smelting & separation products at 50,075 tons, while it was 52,500 tons and 45,000 tons, respectively, for 2016. According to the notice, rare earth control quotas shall be allocated to enterprises that meet the national rare earth industry policies and industrial development planning requirements. 展开更多
关键词 MIIT issued the NOTICE about 2017 the FIRST BATCH of RARE EARTH production control quotas recently
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Quota Distribution System Improved for 2007
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作者 Liu Shuang 《China Textile》 2006年第4期20-22,共3页
After changes having been made in the re- bidding of quotas for textiles exported to the EU and US in 2006, the distribution of quotas for 2007 inherits the amended system, and makes more modifications to improve it.
关键词 quota Distribution System Improved for 2007 THAN US EU DOWN
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2019 rare earths quotas released
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《China Rare Earth Information》 2019年第11期F0001-F0001,2,共2页
MIIT and the Ministry of Natural Resources jointly released the 2019 national rare earths quotas recently.The mining quota for 2019 was 132,000 tons and the smelting&separation quota was127,000 tons.That is a 10%i... MIIT and the Ministry of Natural Resources jointly released the 2019 national rare earths quotas recently.The mining quota for 2019 was 132,000 tons and the smelting&separation quota was127,000 tons.That is a 10%increase from last year's 120,000 tons and 115,000 tons,the"highest quota ever".This also implies a mining quota of 72,000 tons in the second half of 2019,up more than 54%from a year earlier,and the smelting&separation quota of 69,500 tons in the second half. 展开更多
关键词 jointly quota MINING
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Ministry of Water Resources and Ministry of Industry and Information Technology Issued Seven Industrial Water Quotas Including Papermaking
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《造纸信息》 2021年第9期69-69,共1页
On December 30^(th), 2020, in order to further promote water conservation, Ministry of Water Resources and Ministry of Industry and Information Technology issued a notice on seven industrial water quotas including pap... On December 30^(th), 2020, in order to further promote water conservation, Ministry of Water Resources and Ministry of Industry and Information Technology issued a notice on seven industrial water quotas including papermaking, and the quota standard was came into effect on March 1^(st), 2021. 展开更多
关键词 PAPERMAKING MINISTRY quota
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China hikes first rare earth quota of 2022 by 20% to meet surging new energy demand
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《China Rare Earth Information》 2022年第1期22-23,共2页
China has set the first batch of rare earth mining quota for 2022 at 100,800 tons, up about 20% compared with that in 2021, with the smelting & separation quota at 97,200 tons.Quotas for the first half of 2021 wer... China has set the first batch of rare earth mining quota for 2022 at 100,800 tons, up about 20% compared with that in 2021, with the smelting & separation quota at 97,200 tons.Quotas for the first half of 2021 were set at 84,000 tons for mining and 81,000 tons for smelting & separation. An independent industrial analyst said that the 20% jump was mainly due to China’s surging demand for Nd Fe B magnets, amid the new energy push in China. 展开更多
关键词 SEPARATION MINING quota
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使用Quota管理磁盘配额
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作者 王琳 《开放系统世界》 2005年第4期66-67,共2页
笔者学校的内部网建有自己的FTP服务器,可是经常有老师抱怨FTP上面又不能存放文件了。于是登陆到服务器查看,发现FTP的硬盘空间被用光了,原因是有的老师存放了一些电影影片,从而占用了大量的硬盘空间。这种情况影响了FTP的正常使用... 笔者学校的内部网建有自己的FTP服务器,可是经常有老师抱怨FTP上面又不能存放文件了。于是登陆到服务器查看,发现FTP的硬盘空间被用光了,原因是有的老师存放了一些电影影片,从而占用了大量的硬盘空间。这种情况影响了FTP的正常使用,所以很有必要对硬盘的资源进行限制,尤其是对多用户的服务器设定用户的磁盘配额。Quota就是Linux下实现磁盘配额的工具。 展开更多
关键词 校园网 FTP服务器 磁盘配额 quota LINUX 数据文件
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International Trade and the End of Textile Quotas(Part Two)
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作者 Elliot J. Feldman 《China Textile》 2008年第11期34-40,共7页
In last issue, we Published Doctor’s speech on international trade and the end of textile quotas which was highly welcomed,so here is the second part of his analysis:What May Happen When Cases Are BroughtThese,
关键词 International Trade and the End of Textile quotas MORE Part Two THAN
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