An application of genetic algorithm methods for teacher assignment problems

The arrangement of courses at universities is an optimal problem to be discussed under multiple constraints. It can be divided into two parts: teacher assignments and class scheduling. This paper focused primarily on teacher assignments. Consideration was given to teacher's professional knowledge, teacher preferences, fairness of teaching overtime, school resources, and the uniqueness of the school's management. Traditional linear programming methods do not obtain satisfactory results with this complex problem.In this paper, genetic algorithm methods were used to deal with the issue of multiple constraints. As a global optimal searching method, the results of this study indicated that genetic algorithms can save significant time spent on teacher assignments and are more acceptable by the teachers.     

Multi-objective hybrid genetic algorithm for quay crane dynamic assignment in berth allocation planning

The development of containers?? transportation has maintained a high momentum since 1961, especially, the containers?? traffic growth reached 10?C11% in recent years. Container terminals play an important role in the transportation chain, in order to response rapidly for the requirement of modern logistics, better resource allocation, lower cost, and higher operation efficiency are needed. In this paper, we introduce the quay crane dynamic assignment (QCDA) in berth allocation planning problem (BAP) and formulate a multi-objective mathematical model considering each berth for container ship with QCDA and number of Quay Crane??s Move. In order to solve this QCDA in BAP problem, we propose a multi-objective hybrid Genetic Algorithm approach with a priority-based encoding method. To demonstrate the effectiveness of proposed mohGA approach, numerical experiment is carried out and the best solution to the problem is obtained.     

Task assignment using a problem-space genetic algorithm

The task assignment problem is one of assigning tasks of a parallel program among the processors of a distributed computing system in order to reduce the job turnaround time and to increase the throughput of the system. Since the task assignment problem is known to be NP-complete except in a few special situations, satisfactory suboptimal solutions obtainable in a reasonable amount of computation time are generally sought. In the paper we introduce a technique based on the problem-space genetic algorithm (PSGA) for the static task assignment problem in both homogeneous and heterogeneous distributed computing systems to reduce the task turnaround time and to increase the throughput of the system by properly balancing the load and reducing the interprocessor communication time among processors. The PSGA based approach combines the power of genetic algorithms, a global search method, with a simple and fast problem-specific heuristic to search a large solution space efficiently and effectively to find the best possible solution in an acceptable CPU time. Experimental results on test examples from the literature show considerable improvements in both the assignment cost and the CPU times over the previous work. The proposed scheme is also applied to a digital signal processing (DSP) system consisting of 119 tasks to illustrate its balancing properties and computational advantage on a large system. The proposed scheme offers 12–30% improvement in the assignment cost as compared to the previous best known results for the DSP example.     

A dynamic assignment scheduling algorithm for big data stream processing in mobile Internet services

As the huge number of mobile devices (e.g., smart phones, tablets and netbooks) increases, more and more people choose to use the Internet services financed by mobile Internet service providers (MISPs). To provide better services, it is quite necessary for MISPs to analyze the information hidden in the big data stream generated by users. Therefore, processing the real-time big data stream efficiently has become increasingly important. However, traditional static data storage technology fails to meet the demands of real-time data processing. To improve processing capacity, many parallel processing structures are proposed, which brings up the problem about how the parallel devices can be scheduled to maximize their efficiency. Accordingly, a dynamic assignment scheduling algorithm for big data stream processing in mobile Internet services is proposed, and a stream query graph is built to calculate the weight of every edge. The edge with the minimum weight is selected to send tuples. Simulation results show that the proper number of the logic devices can dramatically reduce system response time. Furthermore, system context switching is reduced by increasing the number of tuples sent each time.     

一种启发式多传感器任务实时动态分配算法

传感器任务的分配是传感器管理的重要问题。为提高任务分配的实时性和实效性,基于紧急任务优先、最早完成任务优先、复用能力最小优先和随机分配四条原则,提出了一种启发式多传感器任务实时动态分配算法。计算机模拟仿真表明:该算法既能保证优先级任务较早的执行,又能探测到任务的失败,还能维持传感器负载平衡,是一种快捷、高效的分配算法。     

一种改进的自适应遗传算法求解专家分配问题

基金项目管理中,专家分配问题的研究具有很现实的意义。在解决专家分配问题上做过一些基础性的工作,提出了使用遗传算法及一种信息素指导变异的新算法求解该问题。实验证明,遗传算法是一种可行的途径,并且信息素指导下的启发式变异操作,可以加速算法向最优解搜索。但是,这两种方法都存在局部搜索能力差的问题,在算法运行的中后期会出现大量的冗余迭代。鉴于此,提出一种信息素指导下的自适应变异方法求解专家分配问题。实验证明,新算法具有更强的收敛能力和局部搜索能力。     

A genetic algorithm for the project assignment problem

In this paper we present a genetic algorithm as an aid for project assignment. The assignment problem illustrated concerns the allocation of projects to students. Students have to choose from a list of possible projects, indicating their preferred choices in advance. Inevitably, some of the more popular projects become ‘over-subscribed’ and assignment becomes a complex problem. The developed algorithm has compared well to an optimal integer programming approach. One clear advantage of the genetic algorithm is that, by its very nature, we are able to produce a number of feasible project assignments, thus facilitating discussion on the merits of various allocations and supporting multi-objective decision making.     

Accelerated computation of the genetic algorithm for energy-efficient virtual machine placement in data centers

Neural Computing and Applications - Energy efficiency is a critical issue in the management and operation of cloud data centers, which form the backbone of cloud computing. Virtual machine (VM)...     

SFFS-PC-NN optimized by genetic algorithm for dynamic prediction of financial distress with longitudinal data streams

Recently, research of financial distress prediction has become increasingly urgent. However, existing static models for financial distress prediction are not able to adapt to the situation that the sample data flows constantly with the lapse of time. Financial distress prediction with static models does not meet the demand of the dynamic nature of business operations. This article explores the theoretical and empirical research of dynamic modeling on financial distress prediction with longitudinal data streams from the view of individual enterprise. Based on enterprise’s longitudinal data streams, dynamic financial distress prediction model is constructed by integrating financial indicator selection by using sequential floating forward selection method, dynamic evaluation of enterprise’s financial situation by using principal component analysis at each longitudinal time point, and dynamic prediction of financial distress by using back-propagation neural network optimized by genetic algorithm. This model’s ex-ante prediction efficiently combines its ex-post evaluation. In empirical study, three listed companies’ half-year longitudinal data streams are used as the sample set. Results of dynamic financial distress prediction show that the longitudinal and dynamic model of enterprise’s financial distress prediction is more effective and feasible than static model.     

A new adaptive genetic algorithm for fixed channel assignment

This paper presents a new genetic algorithm (GA) with good convergence properties and a remarkable low computational load. Such features are achieved by on-line tuning up the probabilities of mutation and crossover on the basis of the analysis of the individuals’ fitness entropy. This way, a brand new method to control and adjust the population diversity is obtained. The resulting GA attains quality solutions, thus offering an interesting alternative to other global search techniques, such as simulated annealing, Tabu search and neural networks, as well as to standard GAs. The new algorithm is applied to solve the problem of frequency reuse in mobile cellular communication systems, where the main aim is to obtain a conflict-free channel assignment among the cells such that the resulting bandwidth is close to the minimum channel span required for the whole network. The algorithm performance has been tested and compared by making use of a selection of the most well-known benchmark instances; optimal bandwidth solutions have been achieved within a reasonable computation time.     

A hybrid genetic algorithm for multi-depot homogenous locomotive assignment with time windows

This paper presents a hybrid genetic algorithm to solve a multi-depot homogenous locomotive assignment problem with time windows. The locomotive assignment problem is to assign a set of homogeneous locomotives locating in a set of dispersed depots to a set of pre-schedules trains that are supposed to be serviced in pre-specified hard/soft time windows. A mathematical model is presented, using vehicle routing problem with time windows (VRPTW) for formulation of the problem. A cluster-first, route-second approach is used to inform the multi-depot locomotive assignment to a set of single depot problems and after that we solve each problem independently. Each single depot problem is solved heuristically by a hybrid genetic algorithm that in which Push Forward Insertion Heuristic (PFIH) is used to determine the initial solution and λ-interchange mechanism is used for neighborhood search and improving method. A medium sized numerical example with different scenarios is presented and examined to more clarification of the approach as well as to check capabilities of the model and algorithm. Also some of the results are compared with the solutions produced by branch & bound technique to determine validity and quality of the model. The experiments with a set of 15 completely random generated instance problems indicate that this algorithm is efficient and solves the problem in a polynomial time.     

A genetic algorithm for sequential part assignment for PCB assembly

We present a genetic algorithm for printed circuit board (PCB) assembly, which simultaneously solves the feeder assignment and component sequencing problems. The algorithm uses a unique gene selection procedure that increases the convergence rate without degrading the solution quality. We have compared the performance of our algorithm with existing approaches and have demonstrated improved performance. We have also implemented the algorithm on a Quad IIIc insertion machine for surface mount components. The resulting suboptimal assembly times estimated by the algorithm have been found to be close to the actual optimal values.     

Surface registration using a dynamic genetic algorithm

Robust and fast free-form surface registration is a useful technique in various areas such as object recognition and 3D model reconstruction for animation. Notably, an object model can be constructed, in principle, by surface registration and integration of range images of the target object from different views. In this paper, we propose to formulate the surface registration problem as a high dimensional optimization problem, which can be solved by a genetic algorithm (GA) (Genetic Algorithms in Search Optimization and Machine Learning, Addison-Wesley, Reading, MA, 1989). The performance of the GA for surface registration is highly dependent on its speed in evaluating the fitness function. A novel GA with a new fitness function and a new genetic operator is proposed. It can compute an optimal registration 1000 times faster than a conventional GA. The accuracy, speed and the robustness of the proposed method are verified by a number of real experiments.     

Hybrid shuffled frog leaping algorithm for energy-efficient dynamic consolidation of virtual machines in cloud data centers

Cloud computing aims to provide dynamic leasing of server capabilities as scalable virtualized services to end users. However, data centers hosting cloud applications consume vast amounts of electrical energy, thereby contributing to high operational costs and carbon footprints. Green cloud computing solutions that can not only minimize the operational costs but also reduce the environmental impact are necessary. This study focuses on the Infrastructure as a Service model, where custom virtual machines (VMs) are launched in appropriate servers available in a data center. A complete data center resource management scheme is presented in this paper. The scheme can not only ensure user quality of service (through service level agreements) but can also achieve maximum energy saving and green computing goals. Considering that the data center host is usually tens of thousands in size and that using an exact algorithm to solve the resource allocation problem is difficult, the modified shuffled frog leaping algorithm and improved extremal optimization are employed in this study to solve the dynamic allocation problem of VMs. Experimental results demonstrate that the proposed resource management scheme exhibits excellent performance in green cloud computing.     

Energy-aware framework with Markov chain-based parallel simulated annealing algorithm for dynamic management of virtual machines in cloud data centers

Significant savings in the energy consumption, without sacrificing service level agreement (SLA), are an excellent economic incentive for cloud providers. By applying efficient virtual Machine placement and consolidation algorithms, they are able to achieve these goals. In this paper, we propose a comprehensive technique for optimum energy consumption and SLA violation reduction. In the proposed approach, the issues of allocation and management of virtual machines are divided into smaller parts. In each part, new algorithms are proposed or existing algorithms have been improved. The proposed method performs all steps in distributed mode and acts in centralized mode only in the placement of virtual machines that require a global vision. For this purpose, the population-based or parallel simulated annealing (SA) algorithm is used in the Markov chain model for virtual machines placement policy. Simulation of algorithms in different scenarios in the CloudSim confirms better performance of the proposed comprehensive algorithm.     

Ad hoc网络中TDMA分布式动态时隙分配算法

基于时分多址(TDMA)的时隙分配算法能够提供很好的无线资源利用率,特别是在高负载的环境下.提出了一种适于Ad hoc基于TDMA的无冲突动态分布式时隙分配算法,通过动态改变帧长来控制未用时隙的过量增长,提高了系统吞吐量.该算法通过设置帧长为时隙2的次方,使其在不同帧长的节点中无冲突地包传输.节点间的同步采用本地同步方式.仿真结果表明该算法与IEEE 802.11相比提高了系统吞吐量并降低了端-端延迟.     

Adaptive-mutation compact genetic algorithm for dynamic environments

In recent years, the interest in studying nature-inspired optimization algorithms for dynamic optimization problems (DOPs) has been increasing constantly due to its importance in real-world applications. Several techniques such as hyperselection, change prediction, hypermutation and many more have been developed to address DOPs. Among these techniques, the hypermutation scheme has proved beneficial for addressing DOPs, but requires that the mutation factors be picked a priori and this is one of the limitations of the hypermutation scheme. This paper investigates variants of the recently proposed adaptive-mutation compact genetic algorithm (amcGA). The amcGA is made up of a change detection scheme and mutation schemes, where the degree of change regulates the probability of mutation (i.e. the probability of mutation is directly proportional to the degree of change). This paper also presents a change trend scheme for the amcGA so as to boost its performance whenever a change occurs. Experimental results show that the change trend and mutation schemes have an impact on the performance of the amcGA in dynamic environment and also indicate that the effect of the schemes depends on the dynamics of the environment as well as the dynamic problem being considered.     

基于改进遗传算法的商标多特征权值分配

提出一种改进的遗传算法用于解决商标图像检索中的多特征权值分配问题.针对以往的传统分配方法所存在的不足,提出了利用改进的遗传算法来分配权值.主要方法是将遗传算法中的轮盘赌选择与最优解保存法结合,并将染色体基因重新排列后进行交叉.把遗传算法用于图像检索系统的多特征权值分配,并将得到的特征权值用于商标图像检索系统,目的是为了提高检索系统的效率和精度,而且通过这种方法得到的权值检索出来的结果也比较符合人的视觉感官.     

A genetic algorithm for optimal flow assignment in computer network

In this paper, we consider the optimal flow assignment problem of finding a set of link flows that satisfy the requirements and minimize the average end-to-end network delay for a given topology characterized by the capacities and costs of links. This problem can be formulated as a nonlinear programming problem.

In recent years, a growing body of literature suggests the use of genetic algorithm as one of powerful heuristic search methods to deal with many hard-solving problems. For highly constrained problems, conventional genetic operators often yield illegal solutions in the sense of violation of system constraints.

In this study, we present an implementation of genetic algorithms to the optimal flow assignment problem. Non-uniform mutation and arithmetical crossover are adopted to guarantee the legitimation of offspring. Simulation results show that the proposed approach performs well for this problem.     

Optimizing the distribution of shopping centers with parallel genetic algorithm

This study optimizes the distribution of shopping centers (SCs) to satisfy vendors and shoppers in terms of realizing the shortest car-based shopping trips in an urban area. First, modal split between car and transit is estimated, and then the interaction between land-use and transportation in the context of choice of shopping destinations is modeled to build an optimal function. Second, parallel genetic algorithm (PGA) is used to solve the optimal problem and several problems in application of GA are discussed. Finally, a case study which examines the effectiveness of the method, is carried out.