It is shown that the two-loop recursion for computing the search direction of a limited memory method for optimization can be derived by means of the reverse mode of automatic differentiation applied to an auxiliary function.

Dual-rate G.723.1 speech coder has been widely applied to real-time video and teleconferencing applications where reduced bandwidth and good voice quality is required. This paper presents an efficient implementation of G.723.1 speech coder. To simplify the excitation quantization procedure which is the most computationally demanding, we propose fast algorithms for adaptive codebook and fixed co...

Motion estimation plays a key role in H.264/AVC video coding, but it is the most time-consuming task in the encoding process. In order to reduce the computational complexity of motion estimation in H.264/AVC video coding, this paper proposes a new search algorithm based on artificial fish-swarm algorithm (AFSA) which is a new efficient optimizing method. Firstly, some characteristics of AFSA ar...

In this paper, tuning of power system stabilizer (PSS) and thyristor controlled series capacitor (TCSC) is studied. The analysis of mode controllability is used to select the effective location for TCSC. The performances of TCSC equipped with a proportional-integral-derivative controller (P-I-D controller) and proportional-integral-derivative power system stabilizer (P-I-D PSS) are investigated...

The Minima Hopping global optimization method uses physically realizable molecular dynamics moves in combination with an energy feedback that guarantees the escape from any potential energy funnel. For the purpose of finding reaction pathways, we argue that Minima Hopping is particularly suitable as a guide through the potential energy landscape and as a generator for pairs of minima that can b...

Many gregarious species display rapid fission-fusion dynamics with individuals frequently leaving their groups to reunite or to form new ones soon after. The adaptive value of such ephemeral associations might reflect a frequent tilt in the balance between the costs and benefits of maintaining group cohesion. The lack of information on the short-term advantages of group fission, however, hamper...

Recent research in real-time scheduling for mixed criticality systems has centered on an event-triggered/prioritydriven approach to scheduling. Current practice in many safetycritical domains, however, favors a time-triggered approach. We present here an effective and flexible approach for applying mode changes for time-triggered systems to handle mixed criticality job sets. It is based on a he...

The goals of hub location problems are finding the location of hub facilities and determining the allocation of non-hub nodes to these located hubs. In this work, we discuss the multi-modal single allocation capacitated p-hub covering problem over fully interconnected hub networks. Therefore, we provide a formulation to this end. The purpose of our model is to find the location of hubs and the ...

This paper presents a motion planner that enables a humanoid robot to push an object on a flat surface. The robot’s motion is divided into distinct walking, reaching, and pushing modes. A discrete change of mode can be achieved with a continuous single-mode motion that satisfies mode-specific constraints (e.g. dynamics, kinematic limits, avoid obstacles). Existing techniques can plan well in si...