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A multi-agent system, conformed by differential mobile robots, can execute many tasks. An example is the positioning of mobile robots in order to represent a 2D formation on the ground that represents a geometric shape. In this application, the mobile robots move to a position assigned by an algorithm. This algorithm assigns the 2D position that each mobile robot must achieve. This paper presents a methodology that defines seven criteria necessaries to compute a good 2D position assignation. Those criteria are based on the unweighted Euclidean distances between the robot’s location and the desired position. They are also evaluated in order to select the criterion that allows all robots in the multi-agent system to move the shortest distance when performing a geometric representation. This means a reduction in the length of the path required by each mobile robot to complete the assigned task.

The brain integrates information from different sensory modalities to form a representation of the environment and facilitate behavioral responses. The auditory midbrain or inferior colliculus (IC) is a pivotal station in the auditory system, integrating ascending and descending information from various auditory sources and cortical systems. The present study investigated the modulation of auditory responses in the IC by visual stimuli of different frequencies and intensities in rats using functional MRI (fMRI). Low-frequency (1 Hz) high-intensity visual stimulus suppressed IC auditory responses. However, high-frequency (10 Hz) or low-intensity visual stimuli did not alter the IC auditory responses. This finding demonstrates that cross-modal processing occurs in the IC in a manner that depends on the stimulus. Furthermore, only low-frequency high-intensity visual stimulus elicited responses in non-visual cortical regions, suggesting that the above cross-modal modulation effect may arise from top-down cortical feedback. These fMRI results provide insight to guide future studies of cross-modal processing in sensory pathways.

The data confirm that a decrease in base dimension improves the performance of the bipolar junction transistor. In addition, modifications in design and procedures have improved the quantity and quality of the data collected. The devices produced in this project were functional but not ideal. Nevertheless, this project was able to produce a working BJT device with better performance characteristics than any BJT that has ever been produced in this lab. The designs and methods employed during this project, as well as data collected from this project, will improve the performance quality of future BJT devices produced in this lab.

We fabricated carbon nano-partitions (CNPs) which vertically standing on the metal substrates by radio-frequency magnetron sputtering for dissipating heat applications. Considerable enhancement of the conductive heat transfer has been confirmed and the enhancement depends on the spacing density of nano partitions. The optimum nano-porous density could enhanced the heat transfer when the lower density CNP was made. In our experiments, the enhancement is basically according to the system thermal resistance and it can be reduced by 7.8% to 16.8% which compared with the control samples. Besides, we also make a trial on LEDs. The light output of different colored LEDs responds differently to temperature changes. For the most sensitive color, amber, we can diminish the decrease of light output power by about 15% and the dominant wavelengths shift by about 2nm less than the one is not coated on CNPs.

This paper demonstrates tremor compensation for human subjects using an active handheld micromanipulator. This instrument uses optical and inertial sensing to detect its own motion, estimates tremor using linear filtering, and a flexure-based manipulator to actuate the tip. Compensation results while tracing a line with the tool are presented for both novice users and a trained surgeon. Learning effects from repetition of the trials over a ten-day period are described.

This study aims to examine the presence of a possible third renal autoregulatory mechanism in the very low frequency (VLF) band (approximately 10 mHz) using a high-resolution time- frequency spectral method. Blood pressure and renal blood flow data were measured from conscious and anesthetized Sprague-Dawley and spontaneously hypertensive rats, at the level of the whole kidney (via ultrasound flow probe) and local cortical tissue of a kidney (via laser Doppler flow probe). In addition, N-nitro-L-arginine (LNAME) was used in order to assess the effect of nitric oxide on the third mechanism. Using a complex demodulation method with high time and frequency resolution, a VLF band was often observed, as well as amplitude modulation at the VLF of the two other autoregulation mechanisms. The presence of amplitude modulation is an indication of a particular form of nonlinear interaction between the autoregulatory mechanisms. Physically, such interactions may arise from the fact that all three mechanisms share a common effector, the afferent arteriole. In addition, the magnitude of amplitude modulation of the VLF on the other autoregulatory mechanisms was enhanced by the addition of LNAME, suggesting an important role of nitric oxide in the autoregulatory process.

In this paper, we present a mathematic model designed to identify potential mechanisms responsible for the observed differences in pHi recovery in CO(2)-chemosensitive versus non-chemosensitive cells. The model suggests that differences in pHi regulation may be dependent upon differences in the activation set-point of the internal modifier site of the Na(+)/H(+) exchanger (NHE).