Event-triggered distributed receding horizon control for tracking and formation of homogeneous multi-agent systems

This paper proposes an event-triggered distributed receding horizon control (DRHC) approach for the formation and tracking problems of homogeneous multi-agent systems. For each agent, an event-triggering condition, based on assumed predictive information of the neighbours, is derived from stability analysis. Considering the uncertain deviation between the assumed and true predictive information, we design a time-varying compatibility constraint for the individual optimization problem. In the event-triggered DRHC algorithm, each agent solves the optimization problem and communicates with its neighbours only when the event-triggering condition is satisfied, so the communication and computation burden are reduced. Moreover, guarantees for the recursive feasibility and asymptotic stability of the overall system are proved. A simulation example is provided to illustrate effectiveness of the proposed approach.     

高瓦斯矿井U型通风工作面瓦斯治理技术

针对李雅庄煤矿U型通风工作面上隅角及回风流瓦斯浓度高、瓦斯治理难度大的问题，根据工作面瓦斯来源及在采空区三带的运移储存规律，李雅庄煤矿开展了本煤层抽采工艺优化和裂隙带抽采技术研究。对本煤层钻孔封孔深度、联孔工艺、管路连接方式等进行优化，钻孔抽采浓度由抽采4个月后降低到9%提高到抽采10个月后维持在19%；通过调整裂隙带钻孔布置方式、优化钻孔布孔层位、采取下筛管护孔等技术措施，裂隙带钻场最高瓦斯抽采纯流量达13.6 m³/min，平均瓦斯抽采纯流量达8 m³/min，2个钻场联合抽采瓦斯纯流量在13 m³/min以上；取消了瓦斯措施巷、井下移动泵和上隅角风帘，上隅角和回风流平均瓦斯浓度分别控制在0.5%和0.4%以下，对高瓦斯矿井U型通风工作面瓦斯治理有借鉴意义。     

Distributionally robust optimization of home energy management system based on receding horizon optimization

This paper investigates the scheduling strategy of schedulable load in home energy management system (HEMS) under uncertain environment by proposing a distributionally robust optimization (DRO) method based on receding horizon optimization (RHO-DRO). First, the optimization model of HEMS, which contains uncertain variable outdoor temperature and hot water demand, is established and the scheduling problem is developed into a mixed integer linear programming (MILP) by using the DRO method based on the ambiguity sets of the probability distribution of uncertain variables. Combined with RHO, the MILP is solved in a rolling fashion using the latest update data related to uncertain variables. The simulation results demonstrate that the scheduling results are robust under uncertain environment while satisfying all operating constraints with little violation of user thermal comfort. Furthermore, compared with the robust optimization (RO) method, the RHO-DRO method proposed in this paper has a lower conservation and can save more electricity for users.     

Event-triggered variable horizon Supervisory Predictive control of hybrid power plants

The supervision of a hybrid power plant, including solar panels, a gas microturbine and a storage unit operating under varying solar power profiles is considered. The Economic Supervisory Predictive controller assigns the power references to the controlled subsystems of the hybrid cell using a financial criterion. A prediction of the renewable sources power is embedded into the supervisor. Results deteriorate when the solar power is unsteady, owing to the inaccuracy of the predictions for a long-range horizon of 10 s. The receding horizon is switched between an upper and a lower value according to the amplitude of the solar power trend. Theoretical results show the relevance of horizon switching, according to a tradeoff between performance and prediction accuracy. Experimental results, obtained in a Hardware In the Loop (HIL) framework, show the relevance of the variable horizon approach. Power amplifiers allow us to simulate virtual components, such as a gas microturbine, and to blend their powers with that of real devices (storage unit, real solar panels). In this case, fuel savings, reaching 15%, obtained under unsteady operating conditions lead to a better overall performance of the hybrid cell. The overall savings obtained in the experiments amount to 12%.     

鄂尔多斯盆地东缘临兴区块煤系叠置含气系统及其兼容性

叠置含气系统及其兼容性是煤系多类型非常规天然气合采可行性判识基础。基于临兴区块地层压力、天然气地球化学及生产数据解译,划分了叠置独立含气系统,探讨了含气系统间兼容性。基于地层压力梯度差异认为目标层段至少存在7套独立含气系统;基于产层的天然气甲烷同位素差异,认为太2段、山2~山1段、盒8~盒6段、盒3段等4套层系互不连通;基于天然气生产曲线差异,识别出山西组与石盒子组为2套独立含气系统。综合将研究区自上而下划分为千1~千4段、千5段、盒1~4段、盒5~8段、山1~太1段、太1~太2、本1段及本2段等独立含气系统。提取了地层压力梯度、气层厚度、渗透率及可动水量等影响合采兼容性关键因素,采用最优分割分类方法,指出研究区含气系统兼容性最佳分类数为5~6类,千5段、盒1~4段、盒5~8段等3套叠置含气系统合采兼容性较好。     

地震地貌切片解释技术及应用

时间切片、沿层切片、地层切片、层拉平技术等是目前地震资料地质解释中分析构造、沉积与古地貌等的常用方法。针对沉积体系精细研究的特定需要，提出地震地貌切片的概念并归纳其制作方法。地震地貌切片是指沿地震数据体中反映一定时期古地貌特征的部位制作的一种地震切片类型。地质体空间追踪法和小时窗透视法是地震地貌切片制作的有效方法。地震地貌切片具有对约束层位等时性要求低而适应性广、从古地貌角度出发易于被地质人员理解而实用性强、采用将今论古对比分析方法而预测结果可靠的优势，是利用切片技术进行精细地震沉积分析的一种有效方法。通过实际应用，证实了地震地貌切片概念的科学性、切片制作方法的合理性及分析结果的有效性。     

重庆水晶郦城

水晶郦城环境自然、外观简洁、户型独特,是一个高层低密度的经典实例,是对高层创新性的完美演绎,代表了健康住宅的一个新方向。     

城市天际轮廓线的保护与设计——以重庆主城区天际轮廓线为例

城市天际轮廓线是城市生活事实的物质反映,不同的城市拥有不同的天际轮廓线,它反映了城市的独特性格。在城市建设中,我们应该考虑到城市自身的历史发展脉络和城市所在的地理环境,在城市规划的控制中强调对历史上形成的天际轮廓线进行有效的保护,对城市中建筑和环境的改变要采取谨慎的态度。本文探讨了城市天际轮廓线保护的重要性和城市天际轮廓线保护面临的主要问题,并以重庆为例谈了城市天际轮廓线的设计。     

Surrogate-based optimization of a periodic rescheduling algorithm

Periodic rescheduling is an iterative method for real-time decision-making on industrial process operations. The design of such methods involves high-level when-to-schedule and how-to-schedule decisions, the optimal choices of which depend on the operating environment. The evaluation of the choices typically requires computationally costly simulation of the process, which—if not sufficiently efficient—may result in a failure to deploy the system in practice. We propose the continuous control parameter choices, such as the re-optimization frequency and horizon length, to be determined using surrogate-based optimization. We demonstrate the method on real-time rebalancing of a bike sharing system. Our results on three test cases indicate that the method is useful in reducing the computational cost of optimizing an online algorithm in comparison to the full factorial sampling.