This article proposes indirect/direct learning control schemes for wireless sensor and mobile robot networks to cover an environment according to the density function, which is the distribution of an ...important quantity within the environment. When stationary sensors cooperate with mobile robots, the density estimation can be enhanced by using nonstationary basis functions to relax the assumption of matching conditions in the previous approach. To improve the density function estimation, this study employs an expectation-maximization algorithm and log-likelihood, which maximizes the similarity between the proposed normalized density and normalized coverage function. Subsequently, the adaptive weighting algorithm is combined with the proposed indirect coverage control for tunable basis centers and the weighting of the basis functions. For direct coverage control, mobile robots are driven to cover the regions of higher importance while simultaneously estimating the density function utilizing a sensory model function. We prove that the Lloyd algorithm is a special case of the direct method when the density function and Voronoi partitions are available. The efficiency of the proposed methods is confirmed in numerical examples and semiexperiments.
Drive volley is one of the essential backhand stroke technique trends seen in recent women's tennis competitions. Although movements of the drive volley and groundstroke are similar, activation of ...the internal muscles vary due to different incoming ball conditions. Most previous studies only focused on the groundstroke, however. The current study investigates the different muscle activation patterns in the upper extremity muscle during the two-handed backhand drive volley as well as the groundstroke for female tennis players. Ten elite female tennis players were measured in the muscle activation of the flexor carpi radialis (FCR), extensor carpi radialis (ECR), biceps brachii (BB), and triceps brachii (TB) from both upper extremities. Racket-head speed at impact, swing duration of each phase, and racket-head average velocity in both strokes were also recorded. Significant differences were found between the drive volley and groundstroke in the velocity profile of racket tip, swing duration of each phase (preparation, early follow-through, and late follow-through), activation patterns of upper extremity muscles, and flexor/ extensor ratios of wrist and elbow in both upper extremities. Different racket trajectory strategies were also observed between the two strokes, with greater horizontal racket velocity recorded in the groundstroke but greater vertical velocity in the drive volley. ECR and TB muscle activation during the drive volley preparation phase was greater than the groundstroke when completing a quicker backswing. In the early acceleration phase, the greater FCR leading arm activation in the drive volley assisted wrist stabilization in preparation for impact. In the late follow-through phase, less TB leading arm activity and higher ECR trailing arm activity in the drive volley showed more forward compression movement in racket contact with the ball. As it is essential for the drive volley to complete a quicker backswing and to increase shot efficiency at the end of the forward movement, coaches should consider the two strokes' muscle activation and technique differences to enhance specific techniques and fitness training programs.
Golf putting requires accuracy and precision. However, environmental factors can influence the accuracy and stability of the putt. Therefore, the purpose of this study was to investigate the ...adjustment and stabilization strategies of elite college golfers putting under different wind conditions. A 3 D motion analysis system and two force plates were used to record the kinematic and ground reaction force data of the putting stroke in different conditions of wind and putting stance. The artificial wind was produced from an industrial negative pressure fan to create different wind speeds. Participants were asked to perform three putts to the ‘virtual’ hole with a distance of 15 feet under three wind speeds (none, mid, strong) and three stance width conditions. The results revealed that distance control in strong wind conditions was significantly worse. No significant improvement was found in either distance or direction control when using different stance widths for putting under varying wind speeds. While putting under minor or moderate wind conditions, the player can adjust through self-adjustment on movement control to reduce the impact of external wind on putting performance. However, if the wind speed exceeds to certain threshold value (5.5 m/s), the challenges for golfers to maintain postural stability along the antero-posterior axis increased and led to poor putting distance control. Our results suggest that when putting under windy conditions, elite low-handicap college golfers are able adopt a normal stance in order to minimize a change in their putting protocol.
Cellular proteins are constantly damaged by reactive oxygen species generated by cellular respiration. Because of its metal-chelating property, the histidine residue is easily oxidized in the ...presence of Cu/Fe ions and H2O2 via metal-catalyzed oxidation, usually converted to 2-oxohistidine. We hypothesized that cells may have evolved antioxidant defenses against the generation of 2-oxohistidine residues on proteins, and therefore there would be cellular proteins which specifically interact with this oxidized side chain. Using two chemically synthesized peptide probes containing 2-oxohistidine, high-throughput interactome screening was conducted using the E. coli K12 proteome microarray containing >4200 proteins. Ten interacting proteins were identified, and successfully validated using a third peptide probe, fluorescence polarization assays, as well as binding constant measurements. We discovered that 9 out of 10 identified proteins seemed to be involved in redox-related cellular functions. We also built the functional interaction network to reveal their interacting proteins. The network showed that our interacting proteins were enriched in oxido-reduction processes, ion binding, and carbon metabolism. A consensus motif was identified among these 10 bacterial interacting proteins based on bioinformatic analysis, which also appeared to be present on human S100A1 protein. Besides, we found that the consensus binding motif among our identified proteins, including bacteria and human, were located within α-helices and faced the outside of proteins. The combination of chemically engineered peptide probes with proteome microarrays proves to be an efficient discovery platform for protein interactomes of unusual post-translational modifications, and sensitive enough to detect even the insertion of a single oxygen atom in this case.
This paper proposes an environmental regulating system by using a multi-robot system in cooperation with wireless sensor networks. Wireless sensors pre-deployed in the environment and embedded in ...mobile robots can gather sensory information to estimate the distribution of environmental variable. The environment distribution is illustrated by a density function which is constructed by Gaussian mixture model based on Expectation Maximization (EM) algorithm to estimate real condition. Subsequently, a gradient decent coverage control is proposed to drive the multi-robot system to cover the optimal distribution based on the estimated density function. Meanwhile, the actuators embedded on mobile robots are designed to regulate the environment to achieve a desired value of density function. Numerical examples are illustrated to show the performance of the proposed control system.Keywords: Wireless sensor and actuator networks (WSANs), coverage control, expectation maximization estimation, gradient descent algorithm, Lyapunov-based controller.
The initiatives to add mobility to the Internet and packet data services for next-generation cellular systems are being considered by many mobile service providers. IPv6 is a new version of the ...Internet protocol that was standardized by the Internet Engineering Task Force (IETF). It supports mobility and is presently being standardized by the IETF Mobile IP Working Group. At the same time, cellular is an inevitable and developing architecture for the Personal Communication Service system (PCS). In this paper, cellular mobile IPv6 (CMI), a new algorithm that is migrated from mobile IPv6 is proposed for mobile nodes moving among small wireless cells at high speed. It is important for future mobile communication environments and should eventually, integrate its functions with the Internet. The purpose of this paper is to solve the problems of a communication break within smaller cellular coverage during high-speed movement with packet-switched data or the real-time voice messages. Thus, voice over IP (VoIP) packets were chosen to implement the system. Simulation results show smooth and non-breaking handoff during high-speed movement using the proposed algorithm.
Isothermal vapor–liquid equilibrium (VLE) phase compositions were measured for four binary systems of carbon dioxide with diethylene glycol diethyl ether, diethylene glycol butyl ether, diethylene ...glycol hexyl ether, and diethylene glycol dibutyl ether at temperatures from 333.15 to 413.15
K and pressures up to 20
MPa. The saturated vapor composition of the ethers follows the order of diethylene glycol diethyl ether>diethylene glycol butyl ether>diethylene glycol dibutyl ether>diethylene glycol hexyl ether, while the solubility of carbon dioxide in the liquid obeys the sequence of diethylene glycol diethyl ether≈diethylene glycol dibutyl ether>diethylene glycol hexyl ether ≈ diethylene glycol butyl ether. Henry’s constants were calculated by fitting the Krichevsky–Ilinskaya (KI) equation to the isothermal equilibrium data. The constants increase with increasing temperature for each binary system. The new phase equilibrium data were correlated with several cubic equations of state with the van der Waals one-fluid mixing rules. Generally the Peng–Robinson (PR) equation of state with two binary interaction parameters yielded the best results.
In this paper, Cellular Mobile IPv6 (CMI), a new algorithm that is migrated from Mobile IPv6 is proposed for mobile nodes moving among small wireless cells at high speed. It is important for future ...mobile communication environments and should eventually integrate its functions with the Internet. The purpose of this paper is to solve the problems of communication break within smaller cellular coverage during high-speed movement with packet-switched data or the real-time voice messages. Thus, voice over IP (VoIP) packets were chosen to implement the system. Simulation results show smooth and non-breaking handoff during high-speed movement using the proposed algorithm.
An in-package interconnect for in-package memory application in InFO package has been demonstrated. Technology: TSMC 16FF + InFO. 89.6GByte/s total bandwidth is achieved with 256-DQ operating in ...2.8Gbit/s and 0.3V-swing. Low power: IO (0.062pJ/bit); PHY (0.424pJ/bit). Low latency: Write (4.75T+1.5T=6.25T); Read (2+1.875=3.875T). 0.3V signal integrity on the un-probed IO has been clarified. 420ps (0.84UI) Eye width; 225mV (75%) Eye height. Prompt and automatic timing-calibration scheme.
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