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1.
《International Journal of Hydrogen Energy》2022,47(24):12159-12178
This paper proposes a novel method combining Pinch Methodology and waste hydrogen recovery, aiming to minimise fresh hydrogen consumption and waste hydrogen discharge. The method of multiple-level resource Pinch Analysis is extended to the level of Total Site Hydrogen Integration by considering fresh hydrogen sources with various quality. Waste hydrogen after Total Site Integration is further regenerated. The technical feasibility and economy of the various purification approaches are considered, demonstrated with a case study of a refinery hydrogen network in a petrochemical industrial park. The results showed that fresh hydrogen usage and waste hydrogen discharge could be reduced by 21.3% and 67.6%. The hydrogen recovery ratio is 95.2%. It has significant economic benefits and a short payback period for Total Site Hydrogen Integration with waste hydrogen purification. The proposed method facilitates the reuse of waste hydrogen before the purification process that incurs an additional environmental footprint. In line with the Circular Economy principles, hydrogen resource is retained in the system as long as possible before discharge. 相似文献
2.
This paper describes algorithms that use demand-side management to address large-scale integration of wind power. In particular, demand response (DR) is used to manage wind power intermittency by shifting the time that electrical power system loads occur in response to real-time prices and wind availability. An economic dispatch with transmission, DR capacity and operational constraints is used to model the operation of a transmission constrained system with a high penetration of wind power. This optimization model is used to determine the optimal sizing and distribution of DR given a fixed budget for customer incentives and the installation of enabling technology. We demonstrate the effectiveness of the operational model based on a simple PJM 5-bus system and an IEEE 118-bus system. Simulation results show that transmission constraints have a greater effect on sizing of DR capacity than the location of wind power, which means that buses electrically close to congested lines tend to have higher incentives to deploy DR resources than other buses. The second part of the work examines optimal siting of technology that enables DR based on the frequency of DR based load changes, which are generally a function of the network location. 相似文献
3.
This study assesses the potential of energy flexibility of space heating and cooling for a typical household under different geographical conditions in Portugal. The proposed approach modifies the demand through the optimization of the thermostat settings using a genetic algorithm to reduce either operational costs or interaction with the grid. The results show that the used energy flexibility indicator expresses the available potential and that flexibility depends on several factors, namely: i) thermal inertia of the archetypical household; ii) the time of use electricity tariffs; iii) users’ comfort boundaries; and iv) the geographical location of the houses. 相似文献
4.
The optimization of energy consumption, with consequent cost reduction, is one of the main challenges for the present and future smart grid. Demand response (DR) program is expected to be vital in home energy management system (HEMS) which aims to schedule the operation of appliances to save energy costs by considering customer convenience as well as characteristics of electric appliances. The DR program is a challenging optimization problem especially when the formulations are non-convex or NP-hard problems. In order to solve this challenging optimization problem efficiently, an effective heuristic approach is proposed to achieve a near optimal solution with low computational costs. Different from previously proposed methods in literatures which are not suitable to be run in embedded devices such as a smart meter. The proposed algorithm can be implemented in an embedded device which has severe limitations on memory size and computational power, and can get an optimal value in real-time. Numerical studies were carried out with the data simulating practical scenarios are provided to demonstrate the effectiveness of the proposed method. 相似文献
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本文在分析CIMS环境中数据模式冲关类型的基础上,提出一种互连数据库系统模式结构,论述了在异构数据库集成中解决模式冲突的基本方法.在这种方法体系中,不需要建立整个企业的全局数据模式,各局部DBA以简单的方式定义应用所需的模式变换,系统根据这种定义自动完成各种转换,使用户看到的模式和数据结果与应用要求的一致. 相似文献
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张亚伟 《石油化工安全环保技术》2006,22(1):5-7
通过体系整合的必要性和可行性分析,介绍运用管理的系统方法,以质量管理体系为基础,策划、推进及实施整合型QHSE管理体系的做法,并对各阶段体系建立的方法与措施进行阐述。 相似文献
9.
企业为了实现营销战略目标,必须把各种可控制的营销组合要素,通过商品包装这一特殊的视觉诉求语言充分体现出来,以便综合性地发挥作用,取得良好的市场促销效果。 相似文献
10.
Guay Stéphane; Boisvert Jean-Marie; Freeston Mark H. 《Canadian Metallurgical Quarterly》2003,15(3):392
The goal of this study was to examine whether data from 3 different measures of communication (i.e., self-report, quasi-observational, and observational) can predict relationship adjustment and stability 1 year later when used conjointly in a sample of 62 young couples. The 3 measures of communication were the Communication Skills Test-Revised (CST-R), the Communication Box (CB), and the Demand/Withdraw Pattern Questionnaire (DWPQ). Through hierarchical multiple regression analyses, results revealed that the CST-R and the DWPQ predict both genders' relationship adjustment 1 year later when used conjointly. Logistic regression analyses revealed that none of the measures of communication significantly predicted relationship stability. In conclusion, the combination of the CST-R and the DWPQ appears to be useful for longitudinally predicting relationship adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献