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Quantizers play an important role in discrete-valued input control. This study aims to develop a practical dynamic quantizer design toolbox in Python. This paper first provides some background on dynamic quantizers. Next, an overview of dynamic quantizers, mathematics, and various design methods are described. Then, the developed tool NQLib is described in detail. Furthermore, an example of designing a dynamic quantizer using NQLib is presented. Finally, the impact of NQLib is described.

Objective: To examine the clinical outcomes of optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) in patients presenting with ST-segment elevation myocardial infarction (STEMI). Methods: We retrospectively investigated 533 consecutive patients who underwent primary PCI for STEMI between June 2016 and December 2020. The primary endpoint was a target lesion failure (TLF; defined as a composite of cardiac death, target vessel myocardial infarction, or target lesion revascularization). Propensity score (PS) matching was performed to allow direct comparison of OCT-guided and intravascular ultrasound (IVUS)-guided PCI. Results: Patients in the OCT group (n=166) were younger than those in the IVUS group (n=367) and had a significantly higher left ventricular ejection fraction and estimated glomerular filtration rate. Killip class IV and left main stem disease were more common in the IVUS group. The median peak creatine kinase level was comparable between the two groups (1953 U/L vs 1603 U/L). A significantly larger amount of contrast was used in the OCT group (200 mL vs 165 mL; p

Abstract Single-cell RNA-seq analysis coupled with CRISPR-based perturbation has enabled the inference of gene regulatory networks with causal relationships. However, a snapshot of single-cell CRISPR data may not lead to an accurate inference, since a gene knockout can influence multi-layered downstream over time. Here, we developed RENGE, a computational method that infers gene regulatory networks using a time-series single-cell CRISPR dataset. RENGE models the propagation process of the effects elicited by a gene knockout on its regulatory network. It can distinguish between direct and indirect regulations, which allows for the inference of regulations by genes that are not knocked out. RENGE therefore outperforms current methods in the accuracy of inferring gene regulatory networks. When used on a dataset we derived from human-induced pluripotent stem cells, RENGE yielded a network consistent with multiple databases and literature. Accurate inference of gene regulatory networks by RENGE would enable the identification of key factors for various biological systems.

This paper addresses an optimal path planning problem on the three-input six-dimensional Brockett’s canonical system. This class of systems can be applied to control the position and orientation of a rigid body in SE, such as spacecraft, aerial vehicles, or underwater vehicles, using only three inputs. Since the number of inputs is less than the total number of degrees of freedom, it raises non-trivial technical issues in finding the actual time sequence of control inputs. Here we show that the shortest paths connecting two points are parametrized as helix paths by introducing the input quadratic norm as a Riemannian metric. In addition, we present a quasi-analytical procedure to determine the optimal helix path for any given target point. The characteristic feature of our method is that the optimal paths are parametrized as an explicit function on the state space, which enables the solution paths to be derived without multidimensional iterations. The approach was validated by numerical computations in two aspects: matching for arbitrary target points and covering known optimal paths as special cases. The result that the shortest paths are represented by helices may also help as guidance for solving more general problems numerically, for example, as an initial solution or as a measure on the state space.

Pemphigus foliaceus (PF) is one of the causes of erythroderma; however, to date, there have been relatively few reported cases. We herein describe 6 cases of erythrodermic PF. In all 6 cases, PF was a direct cause of erythroderma because the patients had not undergone any medical treatments and neither had any other skin diseases nor were taking any drugs that typically cause erythroderma. Serum levels of IgE and thymus and activation-regulated chemokine were elevated in 5 of the 6 cases, whereas soluble interleukin-2 receptor and squamous cell carcinoma-related antigen were markedly increased in all cases, suggesting that those markers are strong indicators of skin surface damage. All patients were treated with predonisolon (PSL), of which PSL pulse was added in 4 patients and intravenous immunoglobulin was added in 4 patients. Furthermore, all patients except for one were older adults, among whom 2 cases developed Kaposi’s varicelliform eruption, and died, and another 2 patients, respectively, died of gastrointestinal bleeding and sepsis. Kaposi’s varicelliform eruption is a complication of erythrodermic PF associated with poor prognosis, and thus caution is necessary when considering the diagnosis. Furthermore, elderly people are more likely to have complications due to PSL, which may result in death. Inappropriate treatment and delay in treatment may cause erythroderma, so early diagnosis and treatment are necessary.

Automated driving is attracting attention as a technology that can improve the convenience and comfort of mobility. Research on automated driving continues to develop not only in the approach of vehicle automation but also in the approach of driver assistance. As an example of driver assistance technologies, a system has been proposed in which multiple light sources are placed at equal intervals in a tunnel and blink to encourage drivers to adjust their speed. This system is called a Pace Maker Light (PML). In this paper, we focus on the PML and consider applying it to automatic driving. Therefore, this paper aims to realize the velocity control of an autonomous mobile robot using the PML. First, we modeled the PML and the mobile robot and formulated the design problem of the velocity controller of the robot. Then, we proposed a control law that can achieve velocity control based on the light intensity information obtained from the PML. Finally, we conducted velocity control simulations and experiments with a miniature-scale experimental setup. As a result, it was confirmed that the proposed method could be used to achieve the target speed on a level road and a slope.

Spinal reflex is essential to the robust locomotion of quadruped animals. To investigate the reflex mechanisms, we developed a quadruped robot platform that emulates the neuromuscular dynamics of animals. The leg is designed to be highly back-drivable, and four Hill-type muscles and neuronal pathways are simulated on each leg using software. By searching for the reflex circuit that contributes to the generation of steady gait in cats through robotic experiments, we found a simple reflex circuit that could produce leg trajectories and a steady gait. In addition, this circuit can reproduce the experimental behavior observed in cats. As a major contribution of this study, we show that the underlying structure of the reflex circuit is the reciprocal coupling between extensor muscles via excitatory neural pathways. In the walking experiments on the robot, a steady gait and experimental behaviors of walking cats emerged from the reflex circuit without any central pattern generators. Furthermore, to take advantage of walking experiments using a neurophysiological robotic platform, we conducted experiments in which a part of the proposed reflex circuit was disconnected for a certain period of time during walking. The results showed that the prolongation of the stance phase caused by the reciprocal excitatory reflex contributed greatly to the generation of a steady gait.

In this study, we discovered a phenomenon in which a quadruped robot without any sensors or microprocessor can autonomously generate the various gait patterns of animals using actuator characteristics and select the gaits according to the speed. The robot has one DC motor on each limb and a slider-crank mechanism connected to the motor shaft. Since each motor is directly connected to a power supply, the robot only moves its foot on an elliptical trajectory under a constant voltage. Although this robot does not have any computational equipment such as sensors or microprocessors, when we applied a voltage to the motor, each limb begins to adjust its gait autonomously and finally converged to a steady gait pattern. Furthermore, by raising the input voltage from the power supply, the gait changed from a pace to a half-bound, according to the speed, and also we observed various gait patterns, such as a bound or a rotary gallop. We investigated the convergence property of the gaits for several initial states and input voltages and have described detailed experimental results of each gait observed.

Artificial cilia are promising as a next generation microfluidic device. In this study, we experimentally report that fibrous carbon wires produced by the self-organization process show cilium motions due to induced charge electro-osmosis (ICEO) under AC electric fields in water. In particular, we experimentally demonstrate that the carbon ICEO cilium with a branching wire structure shows asymmetric beating motion. We believe that our findings will contribute to the research of artificial cilia having asymmetrical motions, which would provide net propulsion in a low Reynolds number regime.

In science and engineering using edge-embedded software, it is necessary to demonstrate the validity of results; therefore, the software responsible for operating an edge system is required to guarantee its own validity. The aim of this study is to guarantee the validity of the sampled-time filter and time domain as fundamental elements of autonomous edge software. This requires the update law of a sampled-time filter to be invoked once per every control cycle, which we guaranteed by using the proposed domain specific language implemented by a metaprogramming design pattern in modern C++ (C++11 and later). The time-domain elements were extracted from the software, after which they were able to be injected into the extracted software independent from the execution environment of the software. The proposed approach was shown to be superior to conventional approaches that only rely on the attention of programmers to detect design defects. This shows that it is possible to guarantee the validity of edge software by using only a general embedded programming language such as modern C++ without auxiliary verification and validation toolchains.

We propose a novel virtual torque sensor for commercial low-cost radio-controlled (RC) servo motors. The virtual torque sensor has played an important role for conventional robots. It has been used for torque-required control applications such as human⁻robot interaction and under-actuated robots. However, most virtual torque sensors are based on the inversion of actuators or robot dynamics with the assumption that entire dynamics are known. This is not applicable to the RC servo motors that have unknown control structures. As RC servo motors enable researchers and hobbyists to create lightweight but high performance robots in an easy and cost-effective manner, the development of a virtual torque sensor for these motors is necessary. In this study, we propose a design method of a virtual torque sensor for RC servo motors. First, the virtual sensor is derived mathematically based on internal dynamic models with parametric constraints and compared to the conventional model. Second, a dedicated system identification method is developed for the proposed virtual sensor to implement the sensor in actual experiments. Finally, we compare experimental results with the measurements obtained by an actual sensor.

This article describes an extremely simple controller as a minimal example of decentralized motor coordination and gait generation. The control strategy is based on the stretch reflex in animals and requires no mutual communication or detailed body models. Despite such simplicity, each controller can sync itself and generate various resonant oscillation by only physical interaction through whole body dynamics. To evaluate this controller, we conduct some simulations with a linear spring–mass–damper system and a nonlinear legged robot model with multiple controllers. The former shows an adaptability to change in vibration frequency and the body parameter. In the latter, first we show a limitation of the proposed method due to the nonlinearity, and an alternative method is proposed. Finally, the simple controllers generate versatile gaits just by choosing a control parameter of “speeding up or down,” and the gait generation can be explained by the controllers–body integration based on resonant oscillation.

This paper tries to clarify how rocking motion and body structure effect on the emergence of walking and the changes of the gait such as walking speed and the length of stride. Humans naturally exhibit adaptive performance in various environments. Moreover, they are able to adjust the gait for their purposes. The adaptive locomotion is generated not only with leg swing motion, but also the lateral rocking of the body, rotation of the center of mass, etc. Most previous researches have mainly mentioned the direct drive of the legs. On the other hand, one previous research has indicated interesting motion observation that the body motion in lateral plane will get to a dominant factor in the phase of low speed walking. According to the previous result, we propose an idea that the walking can be generated by an excitation of lateral rocking of the body without direct actuations of legs. Therefore, in this paper, we especially focus our attention on three-dimensional quasi-passive walking provoked by the rocking motion of the robot body in lateral plane. After developing a robot with an oscillator that excites rocking motion of the robot body in lateral plane, we confirmed the emergence of walking in the experiment. Next, we investigated the gait difference by changing the parameters of the rocking motion (amplitude, period) and the robot body structures (length of the leg, offset of the legs to forward). The experimental analyses indicate that the walking speed, robustness and consumption of energy are mainly correlation to the period of lateral rocking and the offset of the legs to forward. In summery, an appropriate combination between the period of rocking motion and structures of the robot body leads to control of the gait.

With the incremental introduction of solar photovoltaic (PV) generators into existing power systems, and their fast-growing share in the gross electricity generation, system voltage stability has become a critical issue. One of the major concerns is voltage fluctuation, due to large and random penetration of solar PV generators. To suppress severe system voltage deviation, reactive power control of the photovoltaic system inverter has been widely proposed in recent works; however, excessive use of reactive power control would increase both initial and operating costs. In this paper, a method for efficient allocation and control of reactive power injection using the sparse optimization technique is proposed. Based on a constrained linearized model describing the influence of reactive power injection on voltage magnitude change, the objective of this study is formulated as an optimization problem, which aims to find the best reactive power injection that minimizes the whole system voltage variation. Two types of formulations are compared: the first one is the conventional least-square optimization, while the second one is adopted from a sparse optimization technique, called the constrained least absolute shrinkage and selection operator (LASSO) method. The constrained LASSO method adds ℓ 1 -norm penalty to the total reactive power injection, which contributes to the suppression of the number of control nodes with non-zero reactive power injection. The authors analyzed the effectiveness of the constrained LASSO method using the IEEE 39-bus and 57-bus power network as benchmark examples, under various PV power generation and allocation patterns. The simulation results show that the constrained LASSO method automatically selects the minimum number of inverters required for voltage regulation at the current operating point.

In this paper, we investigate gathering control of autonomous multiple agents by single mobile robot. This work was motivated by so-called sheepdog harnessing, in which a mobile robot is developed to gather a flock of ducks or sheep and maneuver them to a specified goal position. Based on discrete model of sheepdog system, we apply two different types of control methods to the system. After defining some evaluation indices (harness time, dispersion of flock), we analyze relationship among the parameters of the robot, the sheep and the control algorithms (center-targeting control, tangent-targeting control) by numerical simulations. Moreover, we propose an improved control method to maneuver separate groups of sheep to a goal position based on on-line clustering.

This study examined the association between the outputs of a true random number generator (RNG) and audience size during Japanese professional baseball games. We regarded the RNG as a signal detector of field consciousness and hypothesized that the number of signal sources may increase the ability of an RNG to detect signals. Experimenters and our assistants voluntarily obtained 76 samples from a total of 78 baseball games during the 2010–2011 baseball season. The effects of audience size at the stadium (M = 38970 ± 6058 SD, N = 78) and TV audience ratings (M = 7.07 ± 2.32 SD, N = 23) were examined in relation to the measurements of multiple Random Streamer and Psyleron RNG devices. RNGs set at remote locations ran simultaneously during the games. Our results showed a positive correlation between accumulated chi-squared statistics by Random Streamer and audience size at the stadium. Unexpectedly, identical RNG devices showed strong negative correlations between different machines, which suggested that their outputs canceled each other out. Finally, some future tasks are discussed. Keywords: baseball stadium—MMI—PK—Rpg102—Rpg105—Tokyo Dome

This study examined the possibility that a random number generator (RNG) could detect field consciousness while people watched a film in a movie theater. We conducted 10 measurements at movie theaters showing Departures (Okuribito). One hardware and two software random number generators simultaneously generated random numbers at 512 bits per second. The results showed significant Z-scores derived from chi-squares during the film viewing. But MANOVA using two variables of Z-scores (Stouffer's Z and the Z from chi-squares) showed no significant differences between these conditions because the differences of averages were small in the Stouffer's Z-scores. MANOVA using RNG and pseudo random sequences revealed time-related period effects during film viewing. The biases demonstrated by the three random variables were similar to each other. The similarities between hardware- and software-generated random number sequences were significant when Stouffer's Z-scores were calculated on the basis of 600-second time intervals by averaging all 10 measurements. Audience size has positive effects on the outputs of all the RNGs. Finally, several hypotheses related to RNG biases and future tasks are discussed. Keywords: parapsychology--RPG102--pseudo random numbers--emotion--consciousness--mind-matter interaction--PK