Brain Processes Involved in Motor Planning Are a Dominant Factor for Inducing Event-Related Desynchronization

Event-related desynchronization (ERD) is a relative attenuation in the spectral power of an electroencephalogram (EEG) observed over the sensorimotor area during motor execution and motor imagery. It is a well-known EEG feature and is commonly employed in brain-computer interfaces. However, its underlying neural mechanisms are not fully understood, as ERD is a single variable correlated with external events involving numerous pathways, such as motor intention, planning, and execution. In this study, we aimed to identify a dominant factor for inducing ERD. Participants were instructed to grasp their right hand with three different (10, 25, or 40%MVF: maximum voluntary force) levels under two distinct experimental conditions: a closed-loop condition involving real-time visual force feedback (VF) or an open-loop condition in a feedforward (FF) manner. In each condition, participants were instructed to repeat the grasping task a certain number of times with a timeline of Rest (10.0 s), Preparation (1.0 s), and Motor Execution (4.0 s) periods, respectively. EEG signals were recorded simultaneously with the motor task to evaluate the time-course of the event-related spectrum perturbation for each condition and dissect the modulation of EEG power. We performed statistical analysis of mu and beta-ERD under the instructed grasping force levels and the feedback conditions. In the FF condition (i.e., no force feedback), mu and beta-ERD were significantly attenuated in the contralateral motor cortex during the middle of the motor execution period, while ERD in the VF condition was maintained even during keep grasping. Only mu-ERD at the somatosensory cortex tended to be slightly stronger in high load conditions. The results suggest that the extent of ERD reflects neural activity involved in the motor planning process for changing virtual equilibrium point rather than the motor control process for recruiting motor neurons to regulate grasping force.

Smooth digraphs modulo primitive positive constructability and cyclic loop conditions

Finite smooth digraphs, that is, finite directed graphs without sources and sinks, can be partially ordered via pp-constructability. We give a complete description of this poset and, in particular, we prove that it is a distributive lattice. Moreover, we show that in order to separate two smooth digraphs in our poset it suffices to show that the polymorphism clone of one of the digraphs satisfies a prime cyclic loop condition that is not satisfied by the polymorphism clone of the other. Furthermore, we prove that the poset of cyclic loop conditions ordered by their strength for clones is a distributive lattice, too.

Fuzzy Logic Control Design On Buck Converter For Thermo Electric Air Cooler Power Supply

The air conditioning system that is commonly used today is an Air Conditioner (AC). Unfortunately, this system is a big contributor to global warming. Often times, we find that air conditioners are only used to cool only a small part of a room for individual comfort. Therefore, a new breakthrough is needed from a cooling system that does not use chemicals so that it is environmentally friendly, namely using the Thermo Electric Cooler (TEC) cooling module which utilizes the cold side of the Thermo Electric Cooler (TEC). The size of the DC input voltage on the Thermo Electric Cooler (TEC) is adjusted using a buck converter with fuzzy control. When the buck converter closed loop condition with fuzzy control has a rise time value, the settling time and error percentage have a relatively better value than the open loop condition. When the buck converter set point 40V, the minimum water temperature in the air cooler can be reached 220C, when the buck converter set point is 48V the minimum water temperature in the water cooler can be reached 190C, and when the buck converter set point is 56V the minimum water temperature in the air cooler can be reached 180C. When the water cooler uses air cooler by Peltier, the input air temperature and output air temperature decrease in temperature around 10C. this is caused by the evaporative effect caused by water cooled by the peltier.

PI and PID Controller Design and Analysis for DC Shunt Motor Speed Control

This paper proposes a step by step procedure design and analysis of proportional Integral (PI) and proportional integral derivative (PID) controller. These controllers are employed to control the speed of a DC shunt motor. DC shunt motor Characteristics are modeled in s-function, the speed characteristic of motor is analyzed in open loop condition and closed loop condition without controller and Parameter controlling of PI & PID controller is designed by frequency response analysis. Design, analysis and implementation of PI & PID controller are conducted separately. The performances controllers such as rise time (tr), settling time (ts), steady state error, percent overshoot (%OS), and phase margin are compared to both controllers. Design and analysis of controller are verified by simulation, the results show that PID controller that applied speed control DC shunt motor is better than PI controller.

Open Loop and Closed Loop Power Control Analysis on LTE

LTE downlink is using Orthogonal Frequency Division Multiple Access (OFDMA) multiple access system which have high invulnerability from multipath problem. One of the weakness of OFDM system is the high level from Peak to Average Power Ratio (PAPR) that was required higher level transmit power for maintaining the Bit Error Rate (BER) requirement. Using uplink scheme with Single Carrier FDMA (SC-FDMA) which is OFDMA modification, will be offered better level of PAPR than its conventional OFDM. The main problem of using OFDMA is the high level of PAPR, while using SC-FDMA the problem is intra-cell interference. Intra-cell or inter-cell interference is the common problem that can reduce the LTE performance. Minimizing received power for each users (UE) which is still at acceptable tolerance parameter, can be used for reducing the interference problem to another UE. Power control is the appropriate solution for minimizing the interference level. In this paper will be analyzed the power control using open loop and closed loop scheme at LTE network. The simulation result show that without power control schemes, the transmit power of UE is 23 dBm. While, after applying power control scheme, the transmit power is 18.8 dBm at ?=0.4 of open loop condition and 9.05 dBm at closed loop condition. Using this transmit power value as the UE power can improve the SINR performance. The SINR average value without power control scheme is only 20.38 dB which is lower than using open loop scheme is achieved 22.44 dB and 24.02 dB at closed loop scheme.

Generating Asymptotically Non-terminant Initial Variable Values for Linear Diagonalizable Programs.

We present the key notion of "asymptotically non-terminant initial variable values" for non-terminant loop programs. We show that those specific values are directly associated to inital variable values for which the loop program does not terminate.Considering linear diagonalizable programs, we describe powerful computational methods that generate automatically and symbolically a semi-linear space represented by a linear system of equalities and inequalities. Each element of this space provides us with asymptotically non-terminant initial variable values. Our approach is based on linear algebraic methods and results. We obtain conditions using a decomposition on a specific basis, involving the loop condition and the matrix encoding the instructions of the loop.

A Model for Citizen Scientist Contribution in an Image Tagging Task

Citizen science projects are becoming increasingly popular, yet they typically rely on only a small portion of users for the majority of contribution. In this paper, we propose a model for citizen scientist contribution in an online image tagging task. The model describes participant contribution in response to the performance of a virtual peer, the behavior of which can be controlled by the experimenter. Experimental trials where the virtual peer behaves independent of the participant are used to calibrate the model. The model’s ability to predict participant performance is then verified in a closed-loop condition, where the behavior of the virtual peer is explicitly dependant on the performance of the participant. We foresee this model being a useful tool in the design of web-based citizen science projects, where the behavior of a virtual peer can be used to modulate the performance of contributors in an effort to increase overall levels of contribution.