In an ideal medical environment, real-time coagulation monitoring can enable early detection and prompt remediation of risks. However, traditional Thromboelastography (TEG), a widely employed diagnostic modality, can only provide such outputs after nearly 1 hour of measurement. The delay might lead to elevated mortality rates. These issues clearly point out one of the key challenges for medical AI development: Making reasonable predictions based on very small data sets and accounting for variation between different patient populations, a task where conventional deep learning methods typically perform poorly. We present Physiological State Reconstruction (PSR), a new algorithm specifically designed to take advantage of dynamic changes between individuals and to maximize useful information produced by small amounts of clinical data through mapping to reliable predictions and diagnosis. We develop MDFE to facilitate integration of varied temporal signals using multi-domain learning, and jointly learn high-level temporal interactions together with attentions via HLA; furthermore, the parameterized DAM we designed maintains the stability of the computed vital signs. PSR evaluates with 4 TEG-specialized data sets and establishes remarkable performance -- predictions of R^2 > 0.98 for coagulation traits and error reduction around half compared to the state-of-the-art methods, and halving the inferencing time too. Drift-aware learning suggests a new future, with potential uses well beyond thrombophilia discovery towards medical AI applications with data scarcity.

We propose a novel framework to analyze the coverage performance of three-dimensional (3D) indoor terahertz (THz) communication systems and examine the impact of the location of a user equipment (UE) on such performance. Specifically, we employ Manhattan line processes to precisely characterize the deployment of wall blockages in the indoor environment. Moreover, we model locations of access points (APs) using a Poisson point process and adopt the nearest line-of-sight AP association strategy. Due to the high penetration loss caused by wall blockages, we consider that a UE, its associated AP, and interfering APs are all in the same rectangular area, i.e., a room. Based on the proposed rectangular area model, we first analyze the impact of the location of a UE on the distance to its associated AP. We then derive a new expression for the coverage probability by adopting the fluctuating two-ray distribution to accurately model the small-scale fading in THz communications. Supported by simulation results, we validate our analysis and demonstrate how the location of the UE affects its coverage probability, offering valuable insights for meeting the coverage requirements of future THz communication system deployments.

In this paper, we develop a tractable analytical framework for a three-dimensional (3D) indoor terahertz (THz) communication system to theoretically assess the impact of the pointing error on its coverage performance. Specifically, we model the locations of access points (APs) using a Poisson point process, human blockages as random cylinder processes, and wall blockages through a Boolean straight line process. A pointing error refers to beamforming gain and direction mismatch between the transmitter and receiver. We characterize it based on the inaccuracy of location estimate. We then analyze the impact of this pointing error on the received signal power and derive a tractable expression for the coverage probability, incorporating the multi-cluster fluctuating two-ray distribution to accurately model small-scale fading in THz communications. Aided by simulation results, we corroborate our analysis and demonstrate that the pointing error has a pronounced impact on the coverage probability. Specifically, we find that merely increasing the antenna array size is insufficient to improve the coverage probability and mitigate the detrimental impact of the pointing error, highlighting the necessity of advanced estimation techniques in THz communication systems.

We present comprehensive analysis of the communication and sensing performance of a terahertz (THz) integrated sensing and communication system. Notably, we adopt the multi-cluster fluctuating two-ray (MFTR) model to characterize the small-scale fading of THz transmission with high generality. We derive closed-form expressions for the probability density functions (PDFs) of the communication and sensing signal-to-noise ratios and signal-to-interference-plus-noise ratios, covering both uplink and downlink scenarios under communication-centric and sensing-centric configurations. Based on the PDFs, we further derive the outage probabilities and detection probabilities to evaluate the communication and sensing performance, respectively. Using simulations, we verify the accuracy of our analysis and reveal key insights into the impacts of system parameters, such as fading severity and transmit power, on the system performance.

In this paper, we develop a novel analytical framework for a three-dimensional (3D) indoor terahertz (THz) communication system. Our proposed model incorporates more accurate modeling of wall blockages via Manhattan line processes and precise modeling of THz fading channels via a multi-cluster fluctuating two-ray (MFTR) channel model. We also account for traditional unique features of THz, such as molecular absorption loss, user blockages, and 3D directional antenna beams. Moreover, we model locations of access points (APs) using a Poisson point process and adopt the nearest line-of-sight AP association strategy. Due to the high penetration loss caused by wall blockages, we consider that a user equipment (UE) and its associated AP and interfering APs are all in the same rectangular area, i.e., a room. Based on the proposed rectangular area model, we evaluate the impact of the UE’s location on the distance to its associated AP. We then develop a tractable method to derive a new expression for the coverage probability by examining the interference from interfering APs and considering the MFTR fading experienced by THz communications. Aided by simulation results, we validate our analysis and demonstrate that the UE’s location has a pronounced impact on its coverage probability. Additionally, we find that the optimal AP density is determined by both the UE’s location and the room size, which provides valuable insights for meeting the coverage requirements of future THz communication system deployment.

This paper explores the significance of the timeliness of information in the context of fifth generation (5G) non-terrestrial networks (NTN). As 5G technology continues to evolve, its integration with non-terrestrial components such as satellites, high-altitude platforms, and unmanned aerial vehicles brings about new possibilities and challenges for ensuring the timely delivery of information. In this paper, we delve into the network structure of NTNs and emphasize the significance of timeliness in various applications, including 5G massive Internet of Things and enhanced Mobile Broadband. We conduct an in-depth review of the design technologies and methodologies that enhance the timeliness of information in these applications. These include network architecture design, resource allocation, protocol design, modulation design, trajectory planning, reconfigurable intelligent surfaces design, energy harvesting scheduling design, offloading strategy design, and caching strategy design. By exploring these technical aspects and solutions, we aim to provide valuable insights into ensuring timely information delivery in 5G NTN. Furthermore, we propose potential future research directions to further improve the timeliness of information in NTNs. Recognizing the importance of timeliness and addressing the related challenges will unlock the full potential of 5G NTN, enabling the successful deployment and operation of a wide range of applications and services that depend on real-time data exchange.

We study the age of information (AoI) performance of a multiuser downlink system where a base station generates and transmits status updates to multiple user equipments (UEs). The question of whether to adopt broadcast transmission or distributed transmission for the optimal AoI performance is addressed analytically. In the broadcast transmission scheme, the status update for all UEs is jointly encoded into a packet for transmission, while in the distributed transmission scheme, the status update for each UE is encoded individually and transmitted by following the round robin policy. We first derive new closed-form expressions for the average AoI achieved by two transmission schemes. Then, we provide a criterion for selecting the better transmission scheme for a remote control system. Aided by simulation results, we investigate the impact of system parameters on the average AoI. For example, the distributed transmission scheme is more appropriate for the system with a large number UEs; otherwise, the broadcast transmission scheme is more appropriate.

In this paper, we analyze the non-linear age of information (AoI) performance in a point-to-point short packet communication system, where a transmitter generates packets based on status updates and transmits the packets to a receiver. Specifically, we investigate three packet management strategies, namely, the non-preemption with no buffer strategy, the non-preemption with one buffer strategy, and the preemption strategy. To characterize the level of the receiver's dissatisfaction on outdated data, we adopt a generalized$\alpha-\beta$AoI penalty function into the analysis and derive closed-form expressions for the average AoI penalty achieved by the three packet management strategies. Simulation results are used to corroborate our analysis and explicitly evaluate the impact of various system parameters, such as the coding rate and status update generation rate, on the AoI performance. Additionally, we find that the value of$\alpha$reflects the system transmission reliability.

We analytically decide whether the broadcast transmission scheme or the unicast transmission scheme achieves the optimal age of information (AoI) performance of a multiuser system where a base station (BS) generates and transmits status updates to multiple user equipments (UEs). In the broadcast transmission scheme, the status update for all UEs is jointly encoded into a packet for transmission, while in the unicast transmission scheme, the status update for each UE is encoded individually and transmitted by following the round robin policy. For both transmission schemes, we examine three packet management strategies, namely the non-preemption strategy, the preemption in buffer strategy, and the preemption in serving strategy. We first derive new closed-form expressions for the average AoI achieved by two transmission schemes with three packet management strategies. Based on them, we compare the AoI performance of two transmission schemes in two systems, namely, the remote control system and the dynamic system. Aided by simulation results, we verify our analysis and investigate the impact of system parameters on the average AoI. For example, the unicast transmission scheme is more appropriate for the system with a large number of UEs. Otherwise, the broadcast transmission scheme is more appropriate.

In this paper, we analyze the impact of different encoding schemes on the age of information (AoI) performance in a point-to-point system, where a source generates packets based on the status updates collected from multiple sensors and transmits the packets to a destination. In this system, we consider two encoding schemes, namely, the joint encoding scheme and the distributed encoding scheme. In the joint encoding scheme, the status updates from all the sensors are jointly encoded into a packet for transmission. In the distributed encoding scheme, the status update from each sensor is encoded individually and the sensors’ packets are transmitted following the round robin policy. To ensure the freshness of packets, the zero-wait policy is adopted in both schemes, where a new packet is immediately generated once the source finishes the transmission of the current packet. We derive closed-form expressions for the average AoI achieved by these two encoding schemes and compare their performances. Simulation results show that the distributed encoding scheme is more appropriate for systems with a relatively large number of sensors, compared with the joint encoding scheme.

In this paper, we analyze the age of information (AoI) performance of a multi-user mobile edge computing (MEC) system where a base station (BS) generates and transmits computation-intensive packets to user equipments (UEs). In this MEC system, we consider two computing schemes, namely, the local computing scheme and the edge computing scheme. In the local computing scheme, each packet is transmitted to the UE and then computed by the local server at the UE. In the edge computing scheme, each packet is computed by the edge server at the BS and then transmitted to the UE. Considering exponentially distributed transmission time and computation time and adopting the first come first serve queuing policy, we derive the closed-form expressions for the average AoI of these two computing schemes. Simulation results corroborate our analysis and examine the impact of system parameters on the average AoI.