One-way Signal Research Articles

An Unmanned Traffic Command System for Controlled Waterway in Inland River: An Edge-centric IoT Approach

The controlled waterway in the upper reaches of the Yangtze River has become a bottleneck for shipping due to its curved, narrow and turbulent characteristics. Consequently, the competent authorities must establish controlled one-way waterways and signal stations to ensure traffic safety. These signal stations are often located in remote and uninhabited mountainous areas, causing great difficulties in the living and working conditions for the staff. Therefore, the trend has emerged toward unmanned and remote traffic command at signal stations. The vessels passing through it must obey the signal revealed by the Intelligent Vessel Traffic Signaling System (IVTSS) to pass in one direction. The accuracy of signals is directly related to traffic safety and efficiency. However, the unreliability of vessel sensing sensors in these areas and the latency of transmission and computation of large amounts of sensing data may negatively impact IVTSS. Hence, more information from the physical world is needed to ensure the stable operation of IVTSS, and we proposed an edge-computing-centric sensing and execution system based on IoT architecture to enhance the reliability of IVTSS. We conducted experiments using plug-and-play methods, reducing the command and recording error rates by 89.47% and 86.27%, respectively, achieving the goal of real-time perception control.

One-Way-Signal-Based Localization Method of Multiple Autonomous Underwater Vehicles for Distributed Ocean Surveys

This study proposes a simultaneous localization method of a group of autonomous underwater vehicles (AUVs) based on one-way signals to realize distributed oceanographic surveys. Each AUV group consists of a single high-performance AUV (parent AUV) and the other AUVs (child AUVs). The child AUVs estimate their states (position and heading) based on the parent AUV as a positioning reference. By assuming a situation in which many AUV groups are deployed, the child AUVs can receive positioning signals from multiple parent AUVs. Although only the direction information of the parent AUV can be obtained from a signal from one parent AUV, the child AUVs can estimate their states by receiving signals from different parent AUVs. Sea experiments were conducted using an autonomous buoy and an AUV. The effectiveness of the proposed method was evaluated through a navigation simulation based on the sensor data obtained from the experiments.

Simulation of the impact of tram operations on road network performances

The City government of Semarang has a plan to build a tram way in Semarang Old City Area as a public transportation mode to accommodate tourism activities. The existence of tram way can impact the performance of existing road network due to being built on existing roads side by side with other vehicles. Street network performances discussed in this paper are on the vehicle-kilometres travelled (VKT), and vehicle-hours travelled (VHT), to determine the aforementioned changes, traffic simulation was done with PTV VISSIM software. Vehicle-kilometres travelled decreased by 12,76%, vehicle-hours travelled increased by 10,54%. To minimize the impacts, two mitigation scenarios are simulated, mitigation 1 which is one-way system and mitigation 2 the combination of one-way system and signal optimizations. In mitigation scenario 1 the value of VKT decreased by 13,12%, VHT decreased by 0,65% compared to existing conditions. In mitigation scenario 2 the value of VKT decreased by 17,54%, VHT decreased by 4,93%.

SERIES TERMINATION OF SINGLE-ENDED LVCMOS SIGNALS

For synchronous signals with fast edges traces on printed circuit boards are transmission lines, not just conductor connections. If the length of the PCB trace exceeds certain values, it is necessary to match its impedance with the signal source and/or receiver. Impedance mismatches would bring signal reflections from the source to the receiver and back through the trans- mission line. Such reflection or distortion of the signal is called "echo" or "ringing". It is shown in emissions and irregularities of the waveform, especially the rise and fall edge. In this article, practical guidelines for sequential termination of one-way signals are considered that would resolve such effects. The simulations were done for LVCMOS signals [1].

Optomechanically induced transparency and directional amplification in a non-Hermitian optomechanical lattice

In this paper, we propose a 1-dimensional optomechanical lattice which possesses non-Hermitian property due to its nonreciprocal couplings. We calculated the energy spectrum under periodical boundary condition and open boundary condition, respectively. To investigate the transmission property of the system, we calculate the Green function of the system using non-Bloch band theory. By analyzing the Green function and the periodical boundary condition results, we studied the directional amplification of the system and found the frequency that supports the amplification. By adding probe laser on one site and detect the output of the same site, we found that optomechanically induced transparency (OMIT) can be achieved in our system. Different from the traditional OMIT spectrum, quantum interference due to a large number of modes can be observed in our system. When varying the nonreciprocal and other parameters of the system, the OMIT peak can be effectively modulated or even turned into optomechanically induced amplification. Our system is very promising to act as a one-way signal filter. Our model can also be extended to other non-Hermitian optical systems which may possess topological features and bipolar non-Hermitian skin effect.

An open microfluidic coculture model of fibroblasts and eosinophils to investigate mechanisms of airway inflammation.

Interactions between fibroblasts and immune cells play an important role in tissue inflammation. Previous studies have found that eosinophils activated with interleukin-3 (IL-3) degranulate on aggregated immunoglobulin G (IgG) and release mediators that activate fibroblasts in the lung. However, these studies were done with eosinophil-conditioned media that have the capacity to investigate only one-way signaling from eosinophils to fibroblasts. Here, we demonstrate a coculture model of primary normal human lung fibroblasts (HLFs) and human blood eosinophils from patients with allergy and asthma using an open microfluidic coculture device. In our device, the two types of cells can communicate via two-way soluble factor signaling in the shared media while being physically separated by a half wall. Initially, we assessed the level of eosinophil degranulation by their release of eosinophil-derived neurotoxin (EDN). Next, we analyzed the inflammation-associated genes and soluble factors using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and multiplex immunoassays, respectively. Our results suggest an induction of a proinflammatory fibroblast phenotype of HLFs following the coculture with degranulating eosinophils, validating our previous findings. Additionally, we present a new result that indicate potential impacts of activated HLFs back on eosinophils. This open microfluidic coculture platform provides unique opportunities to investigate the intercellular signaling between the two cell types and their roles in airway inflammation and remodeling.

A study on the characteristic features of the lunar ionosphere using dual frequency radio science (DFRS) experiment onboard Chandrayaan-2 orbiter

ABSTRACT We present ‘first of its kind’ measurements of the enhanced integrated electron density profiles (iEDPs) at the lunar wake and trans-terminator regions using radio occultation (RO) experiments conducted with the dual frequency radio science (DFRS) payload onboard Chandrayaan-2 (CH2) spacecraft. DFRS uses one-way coherent signals at X and S-bands of radio frequencies for RO measurements. Detailed analysis of the results shows that the electron content is large (∼1.5 TECU, with 1 TECU = 1016 m−2) in the lunar wake region compared to the dayside. Large electron content is also seen near lunar polar regions during solar transition periods. These observations are unique in nature as they show post-sunset enhancements in the iEDPs compared to dayside, as reported by earlier missions. These results further confirm recent predictions from the theoretical model for the lunar ionosphere.

Multi-Way Noiseless Signal Amplification in a Symmetrical Cascaded Four-Wave Mixing Process

According to the fundamental laws of quantum optics, vacuum noise is inevitably added to the signal when one tries to amplify a signal. However, it has been recently shown that noiseless signal amplification can be realized when a phase-sensitive process is involved. Two phase-sensitive schemes, a correlation injection scheme and a two-beam phase-sensitive amplifier scheme, are both proposed to realize multi-way noiseless signal amplification in a symmetrical cascaded four-wave mixing process. We theoretically study the possibility of the realization of four-way noiseless signal amplification by using these two schemes. The results show that the correlation injection scheme can only realize one-way noiseless signal amplification, but that the two-beam phase-sensitive amplifier scheme can lead to four-way noise figure values below 1. Our results here may find potential applications in quantum information processing, e.g., the realization of quantum information tap and quantum non-demolition measurement, etc.

Scheduling approach for optical burst switching nodes based on hybrid multipriority algorithm

Optical burst switching (OBS) is a technique involving a switched mechanism for upcoming all-optical backhauls. However, data bursting congestion may occur as a considerable problem due to the increasing amount of light passing through interconnections and the overall system range. Moreover, the lack of restricted buffers for the infrastructure and normal one-way resource signaling exacerbates the conflict, resulting in the deletion of some contesting bursts as a response. In these types of networks, concerns related to contention can be handled by reducing congestion. In response, the quality of service (QoS) and internet connections provided must be precise and consistent. We propose a scheduling approach for satellite excitation and OBS nodes. The proposed method can satisfy the present program’s QoS, requiring a combination of duration, width hybridization limits, and prioritization scheduling. We use a dynamic barrier scheduling approach that incorporates several levels and enhances the changing efficiency compared with a particular threshold approach. To execute this design, a Xilinx xc7vx690tffg1927-2 field-programmable gate array comprises the bulk of a satellite OBS edge module. The scheduler is implemented in Verilog hardware description language and evaluated with ModelSim SE 10.6d using simulated data.

Phonography Culture

Phonography Culture

Sequential TOA-Based Moving Target Localization in Multi-Agent Networks

Localizing moving targets in unknown harsh environments has always been a severe challenge. This letter investigates a novel localization system based on multi-agent networks, where multiple agents serve as mobile anchors broadcasting their time-space information to the targets. We study how the moving target can localize itself using the sequential time of arrival (TOA) of the one-way broadcast signals. An extended two-step weighted least squares (TSWLS) method is proposed to jointly estimate the position and velocity of the target in the presence of agent information uncertainties. We also address the large target clock offset (LTCO) problem for numerical stability. Analytical results reveal that our method reaches the Cramer-Rao lower bound (CRLB) under small noises. Numerical results show that the proposed method performs better than the existing algorithms.

Multiple One-Way Edge States From Reciprocal Continuous Media

One-way edge states are emerging as a robust way to control light in $t\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}p\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}g\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}c\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}l$ $p\phantom{\rule{0}{0ex}}h\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}c\phantom{\rule{0}{0ex}}s$, in which a high gap Chern number is essential for generating multiple one-way edge states for multiplexing and demultiplexing circuits. Contrary to approaches using gyrotropic photonic crystals, this study shows how reciprocal continuous media with a gauge field and chirality can be used to generate a gap Chern number greater than 1, and to support a maximum of 4 one-way edge states. Such media can be further used to construct one-way signal combiners and splitters, in which branching and transmission efficiencies can be accurately controlled.

Active Defense Strategy Selection Method Based on Two-Way Signaling Game

Most network security research studies based on signaling games assume that either the attacker or the defender is the sender of the signal and the other party is the receiver of the signal. The attack and defense process is commonly modeled and analyzed from the perspective of one-way signal transmission. Aiming at the reality of two-way signal transmission in network attack and defense confrontation, we propose a method of active defense strategy selection based on a two-way signaling game. In this paper, a two-way signaling game model is constructed to analyze the network attack and defense processes. Based on the solution of a perfect Bayesian equilibrium, a defense strategy selection algorithm is presented. The feasibility and effectiveness of the method are verified using examples from real-world applications. In addition, the mechanism of the deception signal is analyzed, and conclusions for guiding the selection of active defense strategies are provided.

Single station–based precise positioning system: Multiple‐antenna arrangement for instantaneous ambiguity resolution

A single station–based positioning system is designed as an alternative navigation system for environments for which satellite-based navigation systems are not available. The addition of multiple pseudolite antennae that broadcast one-way continuous signals is considered for the positioning using carrier-phase measurements. This study investigates antenna arrangement considering the cycle ambiguity resolution performance. It presents a new technique, the ambiguity net technique, which assesses whether the antenna arrangement is favorable for easy and fast ambiguity resolution. Moreover, a strategy for the antenna arrangement is presented considering two factors: the positioning accuracy and the cycle ambiguity resolution performance. Simulation-based analyses are conducted to verify the method and strategy presented in this paper and to describe the improved performance of cycle ambiguity resolution.

How Organizations Claim Authenticity: The Coproduction of Illusions in Underground Restaurants

With perceptions of authenticity offering contemporary organizations a key competitive advantage in the marketplace, a growing body of research has investigated “authenticity work”: the diverse ways in which organizational actors fabricate authenticity claims for their audience members. However, claiming authenticity is a challenging and problematic task, because organizations must weigh how much authenticity they can safely project without incurring backfire. This is further complicated by consumers’ fickle and contradictory attitudes regarding authenticity work. This study examines this challenge by asking how organizations can claim authenticity in a way that aligns with their audiences’ variable understandings and expectations. Drawing on a qualitative study of underground restaurants—alternative social dining establishments, also known as “pop-ups” or “supper clubs”—I show that organizers claim authenticity through the coperformance of three illusions: community, transparency, and gift-giving. Instead of rejecting these illusions, most diners and underground organizers knowingly embrace them as authentic. This paper suggests that authenticity work, far from sending a one-way signal that audience members passively accept or reject, involves a continual process that generates the active co-construction of illusions by organizers and their audiences.

A Temporal Signal-Processing Circuit Based on Spiking Neuron and Synaptic Learning.

Time is a continuous, homogeneous, one-way, and independent signal that cannot be modified by human will. The mechanism of how the brain processes temporal information remains elusive. According to previous work, time-keeping in medial premotor cortex (MPC) is governed by four kinds of ramp cell populations (Merchant et al., 2011). We believe that these cell populations participate in temporal information processing in MPC. Hence, in this the present study, we present a model that uses spiking neuron, including these cell populations, to construct a complete circuit for temporal processing. By combining the time-adaptive drift-diffusion model (TDDM) with the transmission of impulse information between neurons, this new model is able to successfully reproduce the result of synchronization-continuation tapping task (SCT). We also discovered that the neurons that we used exhibited some of the firing properties of time-related neurons detected by electrophysiological experiments in other studies. Therefore, we believe that our model reflects many of the physiological of neural circuits in the biological brain and can explain some of the phenomena in the temporal-perception process.

Using the Deep Space Atomic Clock for Navigation and Science.

Routine use of one-way radiometric tracking for deep space navigation and radio science is not possible today because spacecraft frequency and time references that use state-of-the-art ultrastable oscillators introduce errors from their intrinsic drift and instability on timescales past 100 s. The Deep Space Atomic Clock (DSAC), currently under development as a NASA Technology Demonstration Mission, is an advanced prototype of a space-flight suitable, mercury-ion atomic clock that can provide an unprecedented frequency and time stability in a space-qualified clock. Indeed, the ground-based results of the DSAC space demonstration unit have already achieved an Allan deviation of at one day; space performance on this order will enable the use of one-way radiometric signals for deep space navigation and radio science.

Modeling Similarities Among Multi-Dimensional Financial Time Series

Pairs trading is one of the most successful strategies for stock investment. The performance of pairs trading heavily depends on modeling how similarity of two paired financial signals. Conventional methods measure similarity based on one-way or two-way signal, ignoring multiple information sources. In this paper, we propose a tensor-based framework to capture the intrinsic relations among multiple factors. Equities data is represented by tensors in firm-time-trading modes, on which tensor decomposition method is applied to seek a set of multilinear patterns for each mode. In this process, structural information is preserved which provides supplementary information for pairs trading. Experiments on stocks data of all constituent firms of $S \& P 500$ demonstrate the superior performance of the proposed framework when compared with some state-of-the-art methods.

Signaling Architectures that Transmit Unidirectional Information Despite Retroactivity

A signaling pathway transmits information from an upstream system to downstream systems, ideally in a unidirectional fashion. A key obstacle to unidirectional transmission is retroactivity, the additional reaction flux that affects a system once its species interact with those of downstream systems. This raises the fundamental question of whether signaling pathways have developed specialized architectures that overcome retroactivity and transmit unidirectional signals. Here, we propose a general procedure based on mathematical analysis that provides an answer to this question. Using this procedure, we analyze the ability of a variety of signaling architectures to transmit one-way (from upstream to downstream) signals, as key biological parameters are tuned. We find that single stage phosphorylation and phosphotransfer systems that transmit signals from a kinase show a stringent design tradeoff that hampers their ability to overcome retroactivity. Interestingly, cascades of these architectures, which are highly represented in nature, can overcome this tradeoff and thus enable unidirectional transmission. By contrast, phosphotransfer systems, and single and double phosphorylation cycles that transmit signals from a substrate, are unable to mitigate retroactivity effects, even when cascaded, and hence are not well suited for unidirectional information transmission. These results are largely independent of the specific reaction-rate constant values, and depend on the topology of the architectures. Our results therefore identify signaling architectures that, allowing unidirectional transmission of signals, embody modular processes that conserve their input/output behavior across multiple contexts. These findings can be used to decompose natural signal transduction networks into modules, and at the same time, they establish a library of devices that can be used in synthetic biology to facilitate modular circuit design.

Embedded Spherical Localization for Micro Underwater Vehicles Based on Attenuation of Electro-Magnetic Carrier Signals.

Self-localization is one of the most challenging problems for deploying micro autonomous underwater vehicles (AUV) in confined underwater environments. This paper extends a recently-developed self-localization method that is based on the attenuation of electro-magnetic waves, to the AUV domain. We demonstrate a compact, low-cost architecture that is able to perform all signal processing steps present in the original method. The system is passive with one-way signal transmission and scales to possibly large AUV fleets. It is based on the spherical localization concept. We present results from static and dynamic position estimation experiments and discuss the tradeoffs of the system.