多特蒙德工业大学（Technische Universität Dortmund）是德国最著名的理工类高等学府之一，位于德国北莱茵威斯特法伦州的多特蒙德市，始建于1968年，原名多特蒙德大学，2007年11月1日更名为多特蒙德工业大学，跻身于德国为数不多的几个工业大学之列，并连续多年被QS和泰晤士高等教育THE评为全球最成功的年轻大学之一。 2017年THE（Times Higher Education）世界大学排名中排名世界301位。 多特蒙德工业大学作为德国北莱茵威斯特法伦州第二大工业大学，是德国国家支持的重点理工类（TU）大学之一，鲁尔大学联盟（UA Ruhr）成员之一，也是德国北威州重点支持的大学，在电气工程，热力学，计算机，化工，物流工程，机械制造等专业处于德国顶尖水平，为德国老牌工业区鲁尔区培养了大量高素质的劳动力和具有技术科学潜能的人才。 据资料显示，世界最大的化工拜耳40%工程师出自该校BCI系(Fakultät Bio- und Chemieingenieurwesen, 生物与化学工程系)，同时该系与拜耳，巴斯夫等著名化工企业保持紧密联系。此外，大学与西门子集团设计研究的世界第一条单轨悬挂式列车于1984年建成并投入使用至今。
Several sources of flexibility in transmission and, especially, distribution networks are being unlocked by advances in information and communication technologies, aggregators, and new flexibility markets. However, maximizing benefits for both transmission and distribution system operators in a coordinated way requires new algorithms, modeling tools, and modernization of regulatory frameworks. Such approaches must account for uncertainties, the physical and operational constraints of flexibility providers and the grid itself, constraints on information exchange, and scalability, including computational requirements and time constraints. Given the diverse contexts and jurisdictions around the world, there is no single recipe for achieving coordination, but important trends and shared challenges are emerging. This paper surveys the complexities of coordination from technical, market, and technological perspectives, and outlines current practices, proposed approaches, and future research directions to effectively manage, coordinate, model, and leverage flexibility across voltage levels.
The rapid growth of e-commerce has substantially increased parcel volumes and packaging materials, placing growing operational and regulatory pressure on logistics providers to implement viable packaging return systems. Yet the commercial feasibility of these systems depends critically on consumer participation, a behavioural dimension that remains poorly understood. This study examines stated acceptance of three packaging return mechanisms: central package material collection, back mailing of packaging material, and returning packaging material during the next delivery, using questionnaire data collected from 2012 respondents in four European cities: Dortmund, Paris, Trondheim, and Zurich. Acceptance is analysed using a hybrid multivariate ordered probit model, which jointly estimates the attitudinal and behavioural constructs and their effects on acceptance, allowing an assessment of how attitudinal, behavioural, and contextual factors shape acceptance across mechanisms. Results show clear differences in acceptance across the three mechanisms: central collection and return during the next delivery consistently receive higher acceptance, while back mailing receives substantially lower acceptance than both. Environmental concern and shopping frequency consistently increase acceptance across all three mechanisms, while the effects of socio-demographic characteristics are limited and operate largely indirectly through the attitudinal and behavioural constructs. City effects are mechanism-specific, with lower acceptance of back mailing in Paris and of central collection in Trondheim. Together, these findings suggest that packaging return systems can achieve meaningful recovery rates by embedding return within existing delivery interactions and by accounting for the attitudinal and behavioural drivers of participation.
Given a budget and an undirected graph with a cost and a profit function on the edges, the Edge Orienteering Problem asks for a closed walk in the graph that collects the most profit while the sum of costs does not exceed the budget. While the profit is collected only once per edge, the cost is incurred each time the edge is traversed by the walk. In this paper, we present a (4 + epsilon)-approximation algorithm for the Edge Orienteering Problem.
As converter-based generation becomes increasingly dominant, Grid-Forming (GFM) control plays a key role in regulating voltage and frequency. While various strategies have been proposed to improve GFM performance under large disturbances, most of them focus on balanced conditions. This work presents a direct Voltage Control GFM (VCGFM) that enhances the large disturbance stability under unbalanced scenarios. Building on a virtual power-based method previously validated in balanced cases, the VCGFM is extended to integrate a negative sequence control. A current limitation scheme is introduced to limit both positive and negative sequence currents. The proposed control is validated through numerical simulations and experimental tests under diverse balanced and unbalanced grid disturbances. The method aims to preserve the voltage-source behavior of the VCGFM while maintaining synchronization and limiting currents during severe asymmetrical faults.
