Characterization Of Dim Light Response In DVS Pixel: Discontinuity of Event Triggering Time

Over time, more and more systems are becoming mixed-criticality systems. As the complexity and size of these systems grow, computation/communication resources should be more efficient than with traditional systems. Time-triggered (TT) Ethernet is a communication infrastructure that enables the use of a single physical communication infrastructure for distributed mixed-criticality applications while providing timely determinism. TTEthernet distinguishes between two traffic categories: The standard event-triggered (ET) traffic and the TT traffic. The latter, for which higher priority is granted, is subject to strong timing guarantees because of strict-periodicity constraint which fixes start-time cycles of TT messages. In addition, messages in an ET Ethernet traffic, which are of lower priority, have a minimum time interval between their transmission. The focus of this paper is on the timing analysis of a TTEthernet traffic by proposing: (i) A feasibility condition allowing to assess the timing requirements of TT messages. (ii) A schedulability condition allowing to check the schedulability of ET messages by taking into account of TT messages scheduling and idle times.

TTE(Time triggered Ethernet) network combines the flexibility, compatibility, best effort characteristics of our traditional Ethernet and the real-time, reliability and fault tolerance characteristics of time triggered transmission, which can support various types of application services. TTE network mainly includes TT(Time Trigger) service and ET(Event Trigger) service. For the transmission mechanism of traditional Ethernet, it can be understood as a transparent transmission in the TTE network, which means that the reliability of its transmission on the network is not guaranteed. However, for the important data entering the TTE network, we often need to ensure that its transmission will not be disturbed by other services. Based on this problem, this paper proposes how the TTE end system encapsulates and decapsulates a TT special field for ordinary Ethernet data from a Gigabit Ethernet camera. The encapsulation is to add special fields about TT in front of the data and the encapsulated data will successfully complete the transmission in the TTE device. Decapsulation is to remove the encapsulated part, uploads the original data to the PC(Personal Computer) host. At the same time, the end system also counts the bandwidth rate of the two service flow and uploads them to the PC host. For TT service flow, it has the highest priority in TTE network, so as to ensure that camera data will not be disturbed by other services. For comparison test, the end system will also generate a BE (Best effort) service flow into the network for transmission and the BE service belongs to the ET service, so its transmission is not guaranteed. This design is realized through FPGA(Field Programmable Gate Array) and it supports the business in 1G/bps Gigabit Ethernet port transmission, and provides the media access control layer function for the business.

Develop any safety critical system (Automotive, Aerospace, and Medical) requires highly sophisticated software architecture and design patterns. Recent international standards and guidelines also concern about it. Traditional Event Triggered (ET) architecture is not predictable in nature due to the presence of sporadic events and asymmetric interrupts. So after developed, testing and validation of the system becomes very complex. Time Triggered (TT) architecture is predictable because it is not dependent on the sporadic events. In TT approach, system behavior is known at every point in time. In TT approach, blocking of Tasks and Asymmetric interrupts are not allowed. In this work, we've implemented a Safety Critical Real-Time Prototype using both approach and compares it. This paper describes the merits and demerits of both ET and TT approach. At the end, we also implemented TT design patterns using RTOS that is basically an ET framework.

This paper develops solutions for efficient transfer of sporadic (event-triggered) data over a time-triggered communication channel. We present novel and efficient techniques for composite provisioning of the event triggered (ET) and time triggered (TT) paradigms to achieve both the predictability and flexibility inherent in TT and ET systems respectively. As a tangible demonstration of the techniques, present and assess a variation of the TTP/C protocol, where minor operational changes allow for its efficient handling of sporadic message traffic.

Activation of the visual pigment by light in rod and cone photoreceptors initiates our visual perception. As a result, the signaling properties of visual pigments, consisting of a protein, opsin, and a chromophore, 11-cis-retinal, play a key role in shaping the light responses of photoreceptors. The combination of pharmacological, physiological, and genetic tools has been a powerful approach advancing our understanding of the interactions between opsin and chromophore and how they affect the function of visual pigments. The signaling properties of the visual pigments modulate many aspects of the function of rods and cones, producing their unique physiological properties.

All ON pathways are not alike.

Typically the Internet of Things devices are constrained in terms of processing, memory, and energy consumption. Energy consumption is a critical aspect of these devices, being heavily impacted by how programs are developed, and it becomes more evident in interpreted languages that naturally demand more resources. Commonly embedded software development uses Time-triggered (TT) and Event-triggered (ET) architectures to design embedded projects. However, the TT strategy can consume more energy due to the polling method; in contrast, the ET approach can be energy-efficient but cannot deal with multiple events. This paper introduces JSEVAsync, a framework to help developers to design applications using JavaScript language for IoT devices that combine the best parts of TT and ET architectures. This approach uses JavaScript's non-blocking concept as a development interface to structure the algorithms into asynchronous events. To validate it, we compare C- and JavaScript-based applications and analyze the results from the energy consumption perspective. We found that writing code through JSEVAsync can be up to 21% more energy efficient than the traditional method. Moreover, JavaScript can improve design-time aspects such as readability, maintainability, and code reuse.

We can divide the software architectures employed in embedded systems into two categories - time-triggered (TT) and event-triggered (ET) - based on the way in which the various systems tasks are initiated. ET architectures are suitable for use with small systems of limited complexity: as systems grow, it may be necessary to migrate the existing code to a TT architecture. This paper is concerned with techniques which may be used to support the migration between ET and TT architectures.

Rod single-photon responses are critical for vision in dim light. Electrical coupling via gap junction channels shapes the light response properties of vertebrate photoreceptors, but the regulation of rod coupling and its impact on the single-photon response have remained unclear. To directly address these questions, we developed a perforated patch-clamp recording technique and recorded from single rod inner segments in isolated intact neural mouse retinae, maintained by superfusion. Experiments were conducted at different times of the day or under constant environmental conditions, at different times across the circadian cycle. We show that rod electrical coupling is regulated by a circadian clock and dopamine, so that coupling is weak during the day and strong at night. Altogether, patch-clamp recordings of single-photon responses in mouse rods, tracer coupling, receptive field measurements and pharmacological manipulations of gap junction and dopamine receptor activity provide compelling evidence that rod coupling is modulated in a circadian manner. These data are consistent with computer modelling. At night, single-photon responses are smaller due to coupling, but the signal-to-noise ratio for a dim (multiphoton) light response is increased at night because of signal averaging between coupled rods.

Recoverin Improves Rod-Mediated Vision by Enhancing Signal Transmission in the Mouse Retina

It is well known that the pineal hormone melatonin is suppressed by light. The melatonin suppression by dim light has also been suggested as a possible trait marker of bipolar disorder. However, there is large inter individual differences in the light responses. It is possible that methodological factors may contribute to the variable responses observed. Most studies in the past have been conducted in different seasons under different lighting conditions. It is possible the external lighting conditions may affect the melatonin suppression to dim light. Hence we examined the melatonin suppression by dim light in (1) a large group of subjects randomly tested once in one of the four seasons (part one) and (2) small group of subjects tested in all seasons (part two). Subjects were placed in a dark room from 2100 h to 0230 h. Light exposure was between midnight and 0100 h in a sitting position. Blood samples were collected at regular intervals for measurement of plasma melatonin. No statistically significant seasonal differences in the percentage suppression of melatonin were found in both parts of the study (p>0·5). The study suggests that seasonal changes in external lighting do not affect the melatonin suppression by dim light in healthy controls. Copyright © 1999 John Wiley & Sons, Ltd.

It is well known that the pineal hormone melatonin is suppressed by light. The melatonin suppression by dim light has also been suggested as a possible trait marker of bipolar disorder. However, there is large inter individual differences in the light responses. It is possible that methodological factors may contribute to the variable responses observed. Most studies in the past have been conducted in different seasons under different lighting conditions. It is possible the external lighting conditions may affect the melatonin suppression to dim light. Hence we examined the melatonin suppression by dim light in (1) a large group of subjects randomly tested once in one of the four seasons (part one) and (2) small group of subjects tested in all seasons (part two). Subjects were placed in a dark room from 2100 h to 0230 h. Light exposure was between midnight and 0100 h in a sitting position. Blood samples were collected at regular intervals for measurement of plasma melatonin. No statistically significant seasonal differences in the percentage suppression of melatonin were found in both parts of the study (p>0·5). The study suggests that seasonal changes in external lighting do not affect the melatonin suppression by dim light in healthy controls. Copyright © 1999 John Wiley & Sons, Ltd.

Timely message delivery is a key enabler for Internet of Things (IoT) and cyber–physical systems to support a wide range of context-dependent applications. Conventional time-related metrics (e.g., delay and jitter) fail to characterize the timeliness of the system update. Age of Information (AoI) is a time-evolving metric that accounts for the packet interarrival and waiting times to assess the freshness of information. In the foreseen large-scale IoT networks, mutual interference imposes a delicate relation between traffic generation patterns and transmission delays. To this end, we provide a spatiotemporal framework that captures the peak AoI (PAoI) for the large-scale IoT uplink network under time-triggered (TT) and event-triggered (ET) traffic. Tools from the stochastic geometry and queueing theory are utilized to account for the macroscopic and microscopic network scales. Simulations are conducted to validate the proposed mathematical framework and assess the effect of traffic load on the PAoI. The results unveil a counter-intuitive superiority of the ET traffic over the TT in terms of PAoI, which is due to the involved temporal interference correlations. Insights regarding the network stability frontiers and the location-dependent performance are presented. Key design recommendations regarding the traffic load and decoding thresholds are highlighted.

Scheduling Analysis and Optimization for Safety-Critical Automotive Systems

This Time-triggered Ethernet (TTE) is a valid manner to ensure the timeliness, reliability and accuracy of time-triggered (TT) messages which make up for the shortcomings of traditional Ethernet. Satisfiability Modulo Theories (SMT) is the main theory to generate the traditional TTE schedule. However, the calculation time of SMT is too long when the number of time-triggered messages is large. To solve the problem, bin-packing algorithm is applied to the scheduling problem. This paper aims to optimize and improve the bin-packing algorithm including the packing rules and empty box design method based on the principle of the two-staged bin-packing algorithm. With the improved algorithm we proposed, it can ensure the feasibility and porosity of scheduling table. Additionaly, it can also improves the transmission performance of event-triggered (ET) messages without affecting TT messages transmission. The simulation results show that the improved algorithm reduces the latency of the ET messages and greatly shortens the calculation time of the scheduling algorithm.