This study was conducted to examine the yield and quality of tomato fruits grown on a single-truss system shaded during the summer. Tomato seeds were sown on the 10th of every month from February to September and the seedlings were grown in NFT. The plants were covered with cheesecloth at the shading level of 0 (control), 30 (light shading), 55 (medium shading), and 83% (heavy shading) from 10 days after the first anthesis. The nutrient solution was cooled to 25°C from July to September. As the shading level increased, total fruit yield decreased with loss of fruit weight. The total fruit yield of each crop was individually correlated linearly with the mean value of daily integrated solar radiation during fruit development. Regression analysis indicated that the decrease of total fruit yield, corresponding to the loss of 1 MJ·m −2 of the daily integrated solar radiation, would increase from 84 to 100 g/plant if the average air temperature increased from 19 to 27°C. Marketable fruit yield in the control plot was highest in the Feb. crop and significantly lower from Apr. crop to Jul. crops, because of the high incidence of cracked fruits. The incidence of cracked fruits was decreased by shading. It was estimated that shading which decreased daily integrated solar radiation to 5-6 MJ·m −2 effectively increased marketable fruit yields when the air temperature exceeded 25°C. Summer harvested fruits had high titratable acidity. Shading was apt to decrease the brix and increase the titratable acidity of fruits.

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Based on the idea of synergy to explore the building blocks of movements, this study focused on the muscle space for reaching movements by human upper limbs on a horizontal plane to estimate the relationship among muscle synergies, equilibrium-point (EP) trajectories, and endpoint stiffness in two ways: (1) a novel estimation method that analyzes electromyographic signals under the concept of agonistantagonist (A-A) muscle pairs and (2) a conventional estimation method that uses mechanical perturbations. The experimental results suggest that (1) muscle activities of reaching movements by human upper limbs are represented by only three functional muscle synergies; (2) each muscle synergy balances the coactivations of A-A muscle pairs; (3) two of the muscle synergies are invariant bases that form an EP trajectory described in polar coordinates centered on a shoulder joint, where one is a composite unit for radial movement and the other is for angular movement; and (4) the third muscle synergy is the invariant basis for additional adjustment of the endpoint stiffness and has some influence on the direction and size of the endpoint stiffness ellipse.

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Investigation of neural representation of movement planning has attracted the attention of neuroscientists, as it may reveal the sensorimotor transformation essential to motor control. The analysis of muscle synergies based on the activity of agonist–antagonist (AA) muscle pairs may provide insight into such transformations, especially for a reference frame in the muscle space. In this study, we examined the AA concept using the following explanatory variables: the AA ratio, which is related to the equilibrium-joint angle, and the AA sum, which is associated with joint stiffness. We formulated muscle synergies as a function of AA sums, positing that muscle synergies are composite units of mechanical impedance. The AA concept can be regarded as another form of the equilibrium-point (EP) hypothesis, and it can be extended to the concept of EP-based synergies. We introduce, here, a novel tool for analyzing the neurological and motor functions underlying human movements and review some initial insights from our results about the relationships between muscle synergies, endpoint stiffness, and virtual trajectories (time series of EP). Our results suggest that (1) muscle synergies reflect an invariant balance in the co-activation of AA muscle pairs; (2) each synergy represents the basis for the radial, tangential, and null movements of the virtual trajectory in the polar coordinates centered on the specific joint at the base of the body; and (3) the alteration of muscle synergies (for example, due to spasticity or rigidity following neurological injury) results in significant distortion of endpoint stiffness and concomitant virtual trajectories. These results indicate that muscle synergies (i.e., the balance of muscle mechanical impedance) are essential for motor control.

Ultra Wide Band technology has attracted a lot of attention recently as a viable solution for high data rate, low power, short-range wireless link. The growing multi-media home networking is demanding more bandwidth and wireless throughput has become a bottleneck for high quality multi-media services. With the maximum data rate above 100 Mbps, UWB is a perfect solution for such applications.This paper describe such a system that takes advantage of the high data rate offered by UWB. We first implemented the complete MB-OFDM PHY layer using multi-FPGA hardware and discrete RF design. Out implementation is fully compliant to the WiMedia/MBOA PHY specifications and the FCC power regulations. The system achieved 110Mbps maximum data rate with a BER better than 10-6 over a range of 4 meters.Subsequently, we developed a testbed that demonstrates simultaneous transmission of multiple High Definition video streams over the MB-OFDM link. The use-case scenario is a Multimedia Client-Server application where we have one Media Server (transmitter) and several Media Players (receivers). IEEE Consumer Communications and NetworkingThis work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of Mitsubishi Electric Research Laboratories, Inc.; an acknowledgment of the authors and individual contributions to the work; and all applicable portions of the copyright notice. Copying, reproduction, or republishing for any other purpose shall require a license with payment of fee to Mitsubishi Electric Research Laboratories, Inc. All rights reserved.