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1.
Erik Zipperling Benedikt Dahlmann Markus Zdrallek Christian Derksen Stefan Eicker Heiko Serafin 《化学,工程师,技术》2021,93(4):624-631
Demands on production, distribution and consumption of electrical energy change fundamentally with the energy revolution. Energy purchasing costs for inflexible consumers are rising and proceeds of inflexible producers are sinking. Companies are able to reduce costs by marketing operational flexibility options. This article sets out the need of flexibility in the energy system and the new marketing options. Flexibility potentials within infrastructure plants of a chemical park are analyzed, evaluated regarding marketing and activated in the presented research project FlexChemistry. 相似文献
2.
Trevor Sweetnam Michael Fell Eleni Oikonomou Tadj Oreszczyn 《Building Research & Information》2019,47(4):344-361
ABSTRACTElectric heat pumps feature prominently in projected energy transitions in the UK and elsewhere. Owing to their high electricity consumption, heat pumps are viewed as important targets for demand-side response (DSR). Findings are presented from a field trial of a new control system that aims to optimize heat pump performance, including under time-varying tariff conditions. The trial involved monitoring 76 properties with heat pumps, but without dedicated heat storage; 31 of these received the control system. Interviews were conducted with a subsample of 12 participants. The controller successfully evened out electricity demand over the day (reducing the evening peak), but this was associated with increased late night and daytime temperatures. Interview participants reported some disturbance owing to overnight heating and noise, as well as usability issues with the controller interface and hardware. These issues present risks to the future acceptability of such systems. While the system delivered short-term demand reductions successfully, longer-term demand shifting risked causing unacceptable disturbance to occupants. Future control systems could overcome some of the issues identified in this pioneering trial through more effective zoning, using temperature caps or installing dedicated heat storage, but these may either limit the available flexibility or be challenging to achieve. 相似文献
3.
ZL50装载机的换档过程平稳性决定车辆使用寿命和舒适性,这一过程是由多参数变化决定的动态过程,数值模拟方法研究这一过程,对改善车辆参数和性能有很大帮助。利用多自由度变速箱的数码表示方法和拉格朗日能量方程,建立行星变速箱各种档位都适用的通用数学模型,用该模型计算不同档位的运动学和动力学问题,对换档过程进行了数值模拟,得到行星变速箱换档过程各部件的运动学和动力学参数。 相似文献
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By leveraging the secret data coding using the remainder storage based exploiting modification direction (RSBEMD), and the pixel change operation recording based on multi-segment left and right histogram shifting, a novel reversible data hiding (RHD) scheme is proposed in this paper. The secret data are first encoded by some specific pixel change operations to the pixels in groups. After that, multi-segment left and right histogram shifting based on threshold manipulation is implemented for recording the pixel change operations. Furthermore, a multiple embedding policy based on chess board prediction (CBP) and threshold manipulation is put forward, and the threshold can be adjusted to achieve adaptive data hiding. Experimental results and analysis show that it is reversible and can achieve good performance in capacity and imperceptibility compared with the existing methods. 相似文献
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介绍了导致屋面结构层变形的原因及变形量的计算方法,指出屋面防水必须对屋面接缝部位采取重点防护措施,才能经济、有效地防止屋面渗漏,并对重点防护部位的细部构造与施工技术要点进行了论述。 相似文献
6.
选取铜山铜矿具有代表性的铜山矿段1号矿体、前山矿段4号矿体、前山南矿段30号矿体,将地质勘探资料与回采后地质资料所确定的矿体的形态、厚度、底板位移、资源储量等参数进行对比。分析了矿体勘、采资料误差的原因,探讨了合理的生产勘探方法及勘探网度,分析并划分了合理的勘探类型,为类似矿床的勘探、开发提供借鉴。 相似文献
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结合沈阳金秋医院新建疗养病房楼单体设计,对现代医疗建筑中亲和力的塑造进行了有意义的探讨,以寻找医疗建筑中失落的人文关怀;试图从功能、空间、形式、光影、细部的角度阐述亲和力塑造的必要性,以期构建当代人性化的建筑空间。 相似文献
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