Hands are used for communicating with the surrounding environment and have a complex structure that enables them to perform various tasks with their multiple degrees of freedom. Hand amputation can ...prevent a person from performing their daily activities. In that event, finding a suitable, fast, and reliable alternative for the missing limb can affect the lives of people who suffer from such conditions. As the most important use of the hands is to grasp objects, the purpose of this study is to accurately predict gripping force from surface electromyography (sEMG) signals during a pinch-type grip. In that regard, gripping force and sEMG signals are derived from 10 healthy subjects. Results show that for this task, recurrent networks outperform non-recurrent ones, such as a fully connected multilayer perceptron network. Gated recurrent unit and long short-term memory networks can predict the gripping force with
R
-squared values of 0.994 and 0.992, respectively, and a prediction rate of over 1300 predictions per second. The predominant advantage of using such frameworks is that the gripping force can be predicted straight from preprocessed sEMG signals without any form of feature extraction, not to mention the ability to predict future force values using larger prediction horizons adequately. The methods presented in this study can be used in the myoelectric control of prosthetic hands or robotic grippers.
BACKGROUND AND OBJECTIVES: Sustainable development is a process that envisions a desirable future for human societies in which living conditions and resource use meet human needs without compromising ...the integrity, beauty, and stability of vital systems. Knowledge-based companies today are among those companies that act as factories for converting knowledge into goods and services. In this regard, organizational social responsibility can be the basis for the sustainable development of companies and organizations. Therefore, this research aims are to examine the role of the organization’s social responsibility for sustainable development in terms of mediating the participation of employees of knowledge-based companies. METHODS: This research is applied in terms of purpose, descriptive survey and correlation in terms of method. Field and library methods, literature reviews, and standard questionnaires were used to collect information. The statistical population consisted of 578 senior and middle managers of knowledge-based companies in the Science and Technology Park of Sharif University of Technology, Tehran- Iran, and 231 people were sampled using Cochran's formula method and stratified random sampling. A standard questionnaire was also used to collect information. The validity of the questionnaire was checked and confirmed using convergent and divergent validity and confirmatory factor analysis and its reliability using Cronbach's alpha coefficient, joint and combined reliability. Finally, the collected data was analyzed using SPSS and smartPLS software’s.FINDINGS: Based on the results of the Kolmogorov-Smirnov test, the significance of this test was calculated for all indicators less than 0.05 and 0.000, and due to the lack of normal distribution of the data, the smart PLS software was used. The overall fitting criterion was calculated to be 0.551, which means that the model fits well. When testing the main hypothesis, a coefficient of 0.408 was calculated, showing that employee participation explains 40% of the impact of social responsibility on sustainable development. The path coefficient of the sub-hypotheses for these relationships is above 0.5 and the significance is above 1.96. It can be said that the sub-hypotheses of the research are confirmed.CONCLUSION: According to the indicators obtained, the organization’s social responsibility positively and significantly impacts sustainable development and employee participation. The positive role of employee participation in sustainable development was also confirmed. Finally, the results showed that employee participation can mediate the impact of social responsibility on sustainable development.
Four-wave-mixing crosstalk in a fiber-optical parametric amplifier has been reduced by 16 dB by decreasing the fiber length from 340 to 50 m, and increasing the pump power to maintain the gain at 20 ...dB. In this letter, numerical simulations using the split-step Fourier method are presented, showing consistency with experimental observations.
We carried out distributed measurements of the longitudinal gain of fiber-optical parametric amplifiers using a novel sensing technique based on Brillouin optical time-domain analysis. Using this ...technique, we successfully characterized different gain behaviors in the linear and the saturation regimes. In addition, we demonstrated the recently predicted gain reciprocity at opposite ends of the amplifier span
In a recent study, the theory of pulse generation with fiber optical parametric amplification using sinusoidal (clock) intensity modulated pump was revisited. This work showed that the pulses ...generated through such parametric interaction exhibit a shape which depends on the signal detuning with respect to the pump position (i.e. linear phase mismatch). A near Gaussian shape can only be achieved over a small region of the gain spectrum, close to the maximum gain location. Towards the extremities of the gain spectrum, the generated pulses take a near Sinc shape which can have many potential applications such as for all-optical Nyquist limited transmitters and/or receivers. In this paper we experimentally verify the theory at repetition rates up to 40 GHz. We also discuss the impact of noise, pump saturation and walk-off on the generated pulses.
We report an original optical wavelength converter for transparent network and high-speed transmission. Based on an electroabsorption modulator (EAM) in cross-absorption modulation configuration, a ...red-shifted center wavelength filtering of the converted signal decreases the impact of the limited EAM response time. This original and simple device demonstrates wavelength conversion at 40 Gb/s, leading to a reduction of 4.7 dB on the bit-error rate (BER) penalty compared to the case of a centered filter. An absolute 1.8-dB BER power penalty, low switching energy (500 fJ/data pulse) and small applied DC bias are reported.
In this paper, we study theoretically the generation of high repetition rate short pulses using fiber optical parametric amplification. We show that the pulse shape and duration depend on the signal ...location relatively to the pump frequency. We demonstrate that in order to get the shortest pulse width, the signal must be located at one of the extremities of the gain spectrum associated with the pump peak power. We derive the analytical expression of the pulse shape in this case and compare it to the exponential gain regime case. Using numerical simulations, we also analyze the impact of walk-off and pump phase modulation that is required to suppress Stimulated Brillouin Scattering and derive guidelines to design stable train of short and high repetition rate pulses.
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