Analysis of robust optimization for decentralized microgrid energy management under uncertainty

The present paper provides an extended analysis of a microgrid energy management framework based on Robust Optimization (RO). Uncertainties in wind power generation and energy consumption are described in the form of Prediction Intervals (PIs), estimated by a Non-dominated Sorting Genetic Algorithm (NSGA-II) – trained Neural Network (NN). The framework is tested and exemplified in a microgrid formed by a middle-size train station (TS) with integrated photovoltaic power production system (PV), an urban wind power plant (WPP) and a surrounding residential district (D). The system is described by Agent-Based Modelling (ABM): each stakeholder is modeled as an individual agent, which aims at a specific goal, either of decreasing its expenses from power purchasing or increasing its revenues from power selling. The aim of this paper is to identify which is the uncertainty level associated to the “extreme” conditions upon which robust management decisions perform better than a microgrid management based on expected values. This work shows how the probability of occurrence of some specific uncertain events, e.g., failures of electrical lines and electricity demand and price peaks, highly conditions the reliability and performance indicators of the microgrid under the two optimization approaches: (i) RO based on the PIs of the uncertain parameters and (ii) optimization based on expected values.     

Experimentelle und numerische Untersuchungen von Brandszenarien vor Fassaden unter Berücksichtigung verschiedener Abstände

Experimental and numerical investigations of fire scenarios in front of façades considering various distances Constructional boundary conditions, e. g. walls or façades, close to ignition sources affect the fire formation and the plume. It is already known, that boundaries (e. g. walls) constrain the entrainment of air and oxygen into the plume and the combustion of gas or flammable products is completed at larger heights. How far the location of the fire sources, the building geometry and the heat release rate affect the characteristics of a flame is investigated at the Institut für Baustoffe, Massivbau und Brandschutz (iBMB) of TU Braunschweig in line with a series of experiments with a square gas burner. For the implementation of the fire tests the test rig in Braunschweig is provided with extensive measurement techniques to determine heat flux, wall‐bounded temperatures, temperatures for plume measurements and upward velocity. In this paper the data of the fire tests are discussed and compared with the results of a CFD‐Model and selected empirical calculation approaches.     

Simulating the impacts of policy scenarios on the sustainability performance of infrastructure projects

Sustainable development principles have been implemented in various sectors including the construction industry since it was published in the Brundtland Commission Report in 1987. In line with this development, implementation of infrastructure construction projects has been given particular attention as they have more significant impacts on the environment, society and economy. It is considered that proper development and operation of infrastructure projects such as highways can contribute significantly to the mission of sustainable development. However, there is little existing work to provide appropriate methods to assess the sustainability performance of infrastructure projects. The study described in this paper introduces a simulation model, using system dynamics principle, to evaluate the sustainability performance of highway infrastructure projects during the construction and operation stage. The study introduces the indicators which measure the sustainability performance of highway projects and identifies the dynamic factors affecting indicator performance by referring to the relevant feasibility studies of highway projects. A real highway project is presented to demonstrate the application of the simulation model in evaluating the sustainability performance of the project. The case study is used to explore the solutions for improving those poor sustainability performance areas through policy scenarios.     

CLIMATE-CHANGE IMPACTS ON RIVER FLOWS IN BRITAIN: THE UKCIPO2 SCENARIOS

This paper describes the implications of the UKCIPO2 climate-change scenarios for river flows in Britain, focusing on mean monthly runoff and Q95 (i.e. the flow which is exceeded for 95% of the time). By the 2020s. mean summer flows will be about 30% lower than the 1961–1990 mean and Q95 will be reduced by approximately 25%. Percentage reductions are particularly large in southern and eastern England. Mean winter flows are modestly increased, with the greatest increases in the north and west. Reductions in the recharge season result in lower flows in groundwater-dominated catchments throughout the year. The climate-change signal is larger than natural multi-decadal variability - even by the 2020s. This natural variability can add +/- 5% to the changes in Q95 due to climate change.
Changes resulting from the UKCIPO2 scenarios are (a) more extreme during summer than those resulting from earlier climate-change scenarios, showing considerably greater flow reductions, and (b) at the drier end of the range in changes arising from the application of scenarios based on other coarser-resolution climate models.     

Developing an equitable and sustainable mobility strategy for Havana

The particular political, economic and social conditions of the state of Cuba, in the Caribbean, have created unique possibilities for the development of a sustainable transport system in its capital city, Havana. This paper reports on the outcomes of a project to identify the possibilities and priorities for a long-term strategy for equitable and sustainable mobility for Havana. This involved almost 100 participants from Cuba and the UK in the 12 months from June 2013.Overall, the study found a high degree of agreement amongst the transport policy community as to the three key transport issues facing Havana:

• •high level of unmet demand,
• •lack of available financing,
• •poor state of the transport system.

Perhaps more surprisingly, it also produced a near consensus amongst the participants that any future policy should seek to increase the quality of the public transport system by:

• •increasing levels of investment,
• •securing efficiency savings,
• •working ‘smarter’.

However, it also found that this unified view is challenged by a desire for the car market to be deregulated, which would engender a very different policy approach. A strategic choice is needed now, to determine whether Havana follows a North American-style trajectory of rapid growth in car use or a less car-dependent pathway.     

全球5G研究动态和标准进展

总结了国际5G总体进展及趋势,包括国际电信联盟(ITU)在未来用户、业务趋势、5G关键能力需求等方面的核心研究成果和制定的5G工作计划,3GPP的5G工作计划以及欧盟METIS科技项目的主要研究内容及成果;并介绍了NGMN的5G研究动态;最后,介绍了我国IMT-2020推进组在5G愿景、技术场景、关键能力、总体概念和核心技术等方面的研究成果.     

A Methodology for Modeling and Optimizing Social Systems

Abstract

A system methodology for modeling and optimizing social systems is presented. It allows constructing dynamical models formulated stochastically, i.e., their results are given by confidence intervals. The models provide optimal intervention ways to reach the stated objectives. Two optimization methods are used: (1) to test strategies and scenarios and (2) to optimize with a genetic algorithm. The application case presented is a small nonformal education Spanish business. First, the model is validated in the 2008–2012 period, and subsequently, the optimal way to obtain a maximum profit in the 2013–2025 period is obtained using the two methods.     

Experimental investigation of the drying characteristics of a mixed mode natural convection solar crop dryer with back up heater

A mixed mode natural convection solar crop dryer with a backup heater was designed and constructed from locally available materials and used to dry freshly prepared pineapples under four drying Scenarios for drying to correspond to specified drying periods for four typical seasons in Ghana. The experiments were devised for the material moisture content to be monitored continuously till the desired moisture content of between +106% and 184% (d.b) was achieved. In solar heating mode of operation, results show that the thermal mass was capable of storing part of the absorbed solar energy but the quantities involved are insufficient to sustain night drying. It was possible to dry a batch of pineapples in each mode of operation. The dryer reduced the moisture content of pineapple slices from about; 924% to 106% in 19 h; 1049% to 184% in 10 h; 912% to 155% in 7 h; and 1049% to 144% (d.b) in 23 h, for drying in Scenarios 1, 2, 3 and 4, respectively. The average moisture pickup efficiency values obtained were 27%, 24%, 11%, and 32% for drying in Scenarios 1, 2, 3, and 4, respectively.     

The influence of conformity and group identity on drink walking intentions: Comparing intentions to drink walk across risky pedestrian crossing scenarios

Despite the dangers associated with drink walking, limited research is currently available regarding the factors which influence individuals to engage in this risky behaviour. This study examined the influence of psychosocial factors upon individuals’ intentions to drink walk across four experimental scenarios (and a control condition). Specifically, a 2 × 2 repeated measures design was utilised in which all of the scenarios incorporated a risky pedestrian crossing situation (i.e., a pedestrian crossing against a red man signal) but differed according to the level of group identity (i.e., low/strangers and high/friends) and conformity (low and high). Individuals were assessed for their intentions to drink walk within each of these different scenarios. Undergraduate students (N = 151), aged 17–30 years, completed a questionnaire. Overall, most of the study's hypotheses were supported with individuals reporting the highest intentions to drink walk when in the presence of friends (i.e., high group identity) and their friends were said to be also crossing against the red man signal (i.e., high conformity). The findings may have significant implications for the design of countermeasures to reduce drink walking. For instance, the current findings would suggest that potentially effective strategies may be to promote resilience to peer influence as well as highlight the negative consequences associated with following the behaviour of other intoxicated pedestrians who are crossing against a red signal.     

Training for the job: evaluation of a self-defence training programme for correctional officers

Abstract

We investigated to what extent correctional officers were able to apply skills from their self-defence training in reality-based scenarios. Performance of nine self-defence skills were tested in different scenarios at three moments: before starting the self-defence training programme (Pre-test), halfway through (Post-test 1), and after (Post-test 2). Repeated measures analyses showed that performance on skills improved after the self-defence training. For each skill, however, there was a considerable number of correctional officers (range 4–73%) that showed insufficient performance on Post-test 2, indicating that after training they were not able to properly apply their skills in reality-based scenarios. Reality-based scenarios may be used to achieve fidelity in assessment of self-defence skills of correctional officers.

Practitioner summary: Self-defence training for correctional officers must be representative for the work field. By including reality-based scenarios in assessment, this study determined that correctional officers were not able to properly apply their learned skills in realistic contexts. Reality-based scenarios seem fit to detect discrepancies between training and the work field.

Abbreviations: DJI: Dutch National Agency for Correctional Insitutes; ICC: Intraclass Correlation Coefficient