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The article briefly discusses research papers that are contained within the section, titled "Algorithm Design and Scheduling Techniques (Realistic Platform Models) for Heterogeneous Clusters," of this issue. The purpose of these papers is to explore the impact of platform heterogeneity on the design and evaluation of new algorithms, such as, distributed algorithms and scheduling algorithms. One paper by Ligang He and his colleagues discusses two new workload allocation strategies for large-scale heterogeneous platforms. The paper "On the Distribution of Sequential Jobs in Random Brokering for Heterogeneous Computational Grids," by Vandy Berten and colleagues, focuses on resource brokering for scheduling sequential jobs onto a grid platform. In their article, "Multiple Job Scheduling in a Connection-Limited Data Parallel System," authors Alessandro Amoroso and Keith Marzullo describe a new method for scheduling jobs in a distributed system.

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One of the main subjects that is studied in multi-robot applications is allocating tasks to robots and constructing objective-efficient tours for the robots using these allocated tasks. The main purpose of this paper is to allocate tasks via market-based task allocation architecture and to construct collision-free routes for multi-robot systems in a known indoor environment. For task allocation, a market-based architecture is constructed and applied to an example of a team of four heterogeneous mobile robots. In the study, tasks are allocated according to one of two constraints: minimizing the makespan of the robots and maximizing the robot task matching value of each robot in the group. These constraints are achieved by changing the value of a decision parameter. To show the effectiveness of the proposed method, comparisons are made within these constraints. To construct path, a combination of the Nearest Neighbor heuristic and Dijkstra's shortest path algorithms is used. To construct non-conflicting paths, a method that detects and solves collisions is developed. In the study, for agent communication Open Agent Architecture is used. Additionally, simulations on the MobileSim platform are conducted to verify the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

The Hungarian algorithm is one of the most well-known methods in computer science literature. By this method, in each step the cost matrix is systematically reduced to a new matrix in order to obtain an optimal solution for the assignment problem. The subroutine of the algorithm includes determining the minimum number of lines needed to cover all zeros in the reduced cost matrix and modifying the matrix according to the number of lines. In this paper, firstly the methods in literature including the covering all zeros with a minimum number of lines are examined, then a new method is proposed and computational experiments are discussed. [ABSTRACT FROM AUTHOR]

Overall efficiency is an important design parameter of the engine in preliminary design and defined as the ratio of aircraft thrust power to the rate of thermal energy released in the engine. In this paper, effects of the fan pressure ratio and the bypass ratio on engine overall efficiency were investigated for afterburning and separate flow turbofans. With this purpose, fan pressure ratio?bypass ratio?overall efficiency three dimensional graphs were developed and then computer experiment results were evaluated for three different flight Mach number. [ABSTRACT FROM AUTHOR]

In this paper, PI control of a synchronous motor has been realized by using a PIC 18F452 microcontroller and it has been worked as ohmic, inductive and capacitive with different excitation currents. Instead of solving integral operation of PI control which has difficulties with conversion to the digital system, summation of all error values of a defined time period are multiplied with the sampling period. Reference values of the PI algorithm are determined with Ziegler-Nicholas method. These parameters are calculated into the microcontroller and changed according to the algorithm. In addition, this work designed to provide visualization for the users. Current, voltage and power factor data of the synchronous motor can be observed easily on the LCD instantly. [ABSTRACT FROM AUTHOR]

In this paper, an expert system software has been developed and integrated to identify the spur and helical gears, and to extract their detailed dimensions from solid models designed in a CAD system. The STEP files of CAD models of gears have been used as input to the whole system. The algorithm is executed in two main stages. In the first stage, the spur and helical gears are identified by expert system by reasoning STEP physical file of CAD model belonging to any gear and rules represented in a knowledge base constructed for the expert system. In the second stage, detailed dimensions of the identified gears are extracted via data obtained from STEP file. Although the developed approach is only applied to spur and helical gears in this study, it can be successfully implemented to different part families such as bolts, nuts, washers, pipes etc. for other CAD/CAM applications. [ABSTRACT FROM AUTHOR]