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1.
High dimensionality in real-world multi-reservoir systems greatly hinders the application and popularity of evolutionary algorithms, especially for systems with heterogeneous units. An efficient hierarchical optimization framework is presented for search space reduction, determining the best water distributions, not only between cascade reservoirs, but also among different types of hydropower units. The framework is applied to the Three Gorges Project (TGP) system and the results demonstrate that the difficulties of multi-reservoir optimization caused by high dimensionality can be effectively solved by the proposed hierarchical method. For the day studied, power output could be increased by 6.79 GWh using an optimal decision with the same amount of water actually used; while the same amount of power could be generated with 2.59 × 107 m3 less water compared to the historical policy. The methodology proposed is general in that it can be used for other reservoir systems and other types of heterogeneous unit generators.  相似文献   
2.
摘要:为了更好地发挥N元素在Nb微合金化钢筋中的作用,降低生产成本以及为钢筋成分设计提供理论依据。利用金相显微镜、扫描电镜、透射电镜、力学试验机对不同N含量的Nb微合金化高强抗震钢筋进行显微组织表征及力学性能测试,探究N含量对Nb微合金化钢筋的组织与力学性能的影响。研究表明,轧制过程中的奥氏体组织,随着N含量的增加,平均奥氏体晶粒有所减小;最终组织为铁素体和珠光体,随着N含量的增加,铁素体平均晶粒尺寸而减小,片层状珠光体的连续性增加,片层间距减小;析出相Nb(C,N)随着N含量的增大,沉淀析出的第二项颗粒体积分数增大,颗粒尺寸随之减小;在力学性能方面,屈服强度逐渐增加,抗拉强度先增加后减少。  相似文献   
3.
Background subtraction consists of segmenting objects in movement in a video captured by a static camera. This is typically performed using color information, but it leads to wrong estimations due to perspective and illumination issues. We show that multimodal approaches based on the integrated use of color and depth cues produce more accurate and robust results than using either data source independently. Depth is less affected by issues such as shadows or foreground objects similar to background. However, objects close to the background may not be detected when using only range information, being color information complementary in those cases. We propose an extension of a well-known background subtraction technique which fuses range and color information, as well as a post-processing mask fusion stage to get the best of each feature. We have evaluated the method proposed using a well-defined dataset and different disparity estimation algorithms, showing the benefits of our method for fusion color and depth cues.  相似文献   
4.
为了研究某一高层建筑在大震作用下的损伤情况,本文采用Midas Building有限元软件对该建筑进行推覆分析.由计算结果知,该结构在大震作用下,最大弹塑性层间位移角为:X向1/219,Y向1/566,均满足规范[1~2]要求的最低标准1/120.根据计算结果,对本工程结构构件进行抗震性能评价,剪力墙、框架柱均未屈服,连梁与框架梁出现塑性铰,但均未达到CP状态[3].结果表明结构能满足抗震性能设计的要求,达到了大震不倒的抗震设防目标.  相似文献   
5.
海底管线钢管强度是包辛格效应和形变强度共同作用的结果。采用MTS材料试验机、扫描电镜和透射电镜,研究了不同预压变形量下X65MO海底管线钢的包辛格效应。研究结果表明,预压变形量在0~0.85%时,包辛格效应占据主导作用,X65MO钢管的屈服强度较原料带钢的低,当预压变形量约为0.30%时,屈服强度下降值达到最大约30 MPa;预压变形量在085%~1.50%时,形变强化效应占主导作用,X65MO钢管的屈服强度较原料带钢的高。随着预压变形量的增加,X65MO钢晶粒内部形成的稳定位错亚结构增多,并且第二相粒子对位错钉扎作用更加显著,导致了宏观上钢管屈服强度的增加。  相似文献   
6.
In Information Technology Service Management (ITSM), network management teams typically use an Incident Ticket System (ITS) as a tool to track, troubleshoot, and coordinate the resolution of network incidents that occur during the daily operation of the network. A well organized ITS may positively impact on the efficiency of the incident management process. Nevertheless, in many cases the handling of tickets by the management team is not completely systematic and may be incoherent and inefficient. This way, irrelevant or redundant tickets for the same incident may be issued, thus creating a redundancy in the system that leads to inefficiencies. In this paper, we suggest a model aimed to correlate redundant tickets in order to reduce the information to a single ticket per incident. We validate the proposed correlation model by evaluating it with two datasets taken from a real ticketing system of a telecommunications network company. Using this model as a basis, we also develop and evaluate a methodology that assesses the efficiency of the management team during the process of tickets creation and management. Based on it, we also get some insights on the performance of the different management groups involved in the ticket creation process. These analyses can be leveraged for improving both the management groups functioning and the policies for the tickets’ creation.  相似文献   
7.
Wang  Lin  Wang  Xin  Li  Tao  Zheng  Ruijuan  Zhu  Junlong  Zhang  Mingchuan 《Neural computing & applications》2023,35(11):8051-8063
Neural Computing and Applications - Adaptive (sub)gradient methods have received wide applications such as the training of deep networks. The square-root regret bounds are achieved in convex...  相似文献   
8.
Xu  Junwei  Zheng  Ruijuan  Yang  Lei  Liu  Muhua  Song  Jianqiang  Zhang  Mingchuan  Wu  Qingtao 《The Journal of supercomputing》2022,78(12):14504-14529
The Journal of Supercomputing - In the edge computing, service placement refers to the process of installing service platforms, databases, and configuration files corresponding to computing tasks...  相似文献   
9.
铝锌镁合金以其优异的力学性能广泛应用于航空、航天、交通运输等工业领域,而铝合金的细化一直是铝加工行业的研究重点.为细化晶粒并提高其力学性能,本文将传统细化剂Al-Ti-B与RE复合添加到铝锌镁合金中,借助于XRD、光学显微镜、扫描电镜、拉伸实验等测试方法研究了不同细化剂对Al7Zn2.4Mg合金组织及其力学性能的影响.试验结果表明,合金中加入Al-5Ti-B和Al-Zr-Er后细化效果明显,单独添加Al-Ti-B的细化效果最好,但仍有少部分的晶粒保留的树枝晶形态.随着Al-Ti-B和Al-Zr-Er添加量的增多,合金的晶粒发生明显变化,塑性也随之增加,其中,添加0.4wt.%Al-5Ti-B细化剂对合金的塑性影响最大,而抗拉强度呈先增大后减小的趋势,复合添加0.2wt.%Al-2Zr-Er和0.2wt.%Al-5Ti-B细化剂的合金晶粒圆整且未出现树枝晶,晶界析出物最少平均抗拉强度最高.Al-Ti-B和Al-Zr-Er均可细化铸态铝锌镁合金的晶粒,同时添加两种细化剂更有利于提高合金的综合力学性能.  相似文献   
10.
The classification of various types of processes is an important factor in large-scale distributed systems such as, grid and cloud platforms. Moreover, the coordination and control of distributed processes are research challenges in presence of unpredictable network partitioning and distributed semaphores. The process classification is important in order to allocate and schedule distributed processes enhancing overall resource utilization and throughput. The schedulers employ patterns of resource affinities of concurrent processes in order to make scheduling decisions affecting overall resource utilization in a system, where resource affinity patterns of a process may not be static. This paper proposes an estimation model and a classifier algorithm to queuing processes based on respective resource affinities. The kernel-level software architecture is designed to control scheduling of distributed processes based on classification for enhanced throughput. The classifier algorithm tracks the resource affinities of processes based on execution traces and the control algorithm performs process scheduling. Experimental results indicate that the classifier algorithm successfully manages process queues based on resource affinities of processes and, the control algorithm successfully monitors scheduler activation for a set of processes.  相似文献   
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