Search

The Open Radio Access Network (O-RAN), an industry-driven initiative, utilizes intelligent Radio Access Network (RAN) controllers and open interfaces to facilitate efficient spectrum sharing between LTE and NR RANs. In this paper, we introduce the Proactive Spectrum Adaptation Scheme (ProSAS), a data-driven, O-RAN-compatible spectrum sharing solution. ProSAS is an intelligent radio resource demand prediction and management scheme for intent-driven spectrum management that minimizes surplus or deficit experienced by both RANs. We illustrate the effectiveness of this solution using real-world LTE resource usage data and synthetically generated NR data. Lastly, we discuss a high-level O-RAN-compatible architecture of the proposed solution., Comment: Accepted for publication at IEEE International Conference on Communications (ICC) 2024

Membraneless microfluidic fuel cells (MFCs) have garnered tremendous interest as micropower devices, which exploit the colaminar nature of two aqueous electrolytes to separate the anode and cathode and avoid the membrane usually used in a fuel cell. Our previous research shows that the performance of FeCl3-based MFCs with catalyst-free cathodes is mainly limited by the cathode. To improve the power output of these MFCs, we activated the carbon paper cathode by an electrochemical method in the three solutions (Na2SO4, NaOH, and H2SO4) to improve the electrochemical characteristics of the carbon paper cathode. The surface functionalities and defects, reduction activation of iron ions as the oxidant, cathode resistance, and performance of FeCl3-based MFCs were measured and compared. Our work shows that the electrochemical activation of the carbon paper in different solutions is a simple and effective method to enhance the electrochemical characteristics of the carbon paper cathode and improve the performance of the FeCl3-based MFC. Also, the MFC with the carbon paper cathode activated in the H2SO4 solution reaches the optimum performance: 235.6 mW cm-3 in volumetric power density and 1063.33 mA cm-3 in volumetric limiting current density, which are 1.58 and 1.52 times as much as that of a MFC with an untreated carbon paper cathode, respectively. This best performance can be attributed to the cathode activated in the H2SO4 solution with the largest number of oxygen-containing functional groups, the largest electrochemical active surface area, strongest reduction of iron ions, and least resistance of the cathode.

Membraneless microfluidic fuel cells (MFCs) have garnered tremendous interest as micropower devices, which exploit the colaminar nature of two aqueous electrolytes to separate the anode and cathode and avoid the membrane usually used in a fuel cell. Our previous research shows that the performance of FeCl3-based MFCs with catalyst-free cathodes is mainly limited by the cathode. To improve the power output of these MFCs, we activated the carbon paper cathode by an electrochemical method in the three solutions (Na2SO4, NaOH, and H2SO4) to improve the electrochemical characteristics of the carbon paper cathode. The surface functionalities and defects, reduction activation of iron ions as the oxidant, cathode resistance, and performance of FeCl3-based MFCs were measured and compared. Our work shows that the electrochemical activation of the carbon paper in different solutions is a simple and effective method to enhance the electrochemical characteristics of the carbon paper cathode and improve the performance of the FeCl3-based MFC. Also, the MFC with the carbon paper cathode activated in the H2SO4 solution reaches the optimum performance: 235.6 mW cm-3 in volumetric power density and 1063.33 mA cm-3 in volumetric limiting current density, which are 1.58 and 1.52 times as much as that of a MFC with an untreated carbon paper cathode, respectively. This best performance can be attributed to the cathode activated in the H2SO4 solution with the largest number of oxygen-containing functional groups, the largest electrochemical active surface area, strongest reduction of iron ions, and least resistance of the cathode.

5G New Radio (NR) promises to support diverse services such as enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC). This requires spectrum, most of which is occupied by 4G Long Term Evolution (LTE). Hence, network operators are expected to deploy 5G using the existing LTE infrastructure while migrating to NR. In addition, operators must support legacy LTE devices during the migration, so LTE and NR systems will coexist for the foreseeable future. In this article, we address LTE-NR coexistence starting with a review of both radio access technologies. We then describe the contributions by the 3rd Generation Partnership Project (3GPP) to solving the coexistence issue and catalog the major coexistence scenarios. Lastly, we introduce a novel spectrum sharing scheme that can be applied to the coexistence scenarios under study.

Shunxin Zhu,1 Caixiu Zeng,2 Yan Zou,1 Yanjiao Hu,1 Canfang Tang,1 Chunmei Liu2 1Clinical Laboratory, The Maternity & Child Health Care Hospital of Xiangtan City, Xiangtan City, Hunan Province, 411100, People’s Republic of China; 2Department of Pediatrics, The Maternity & Child Health Care Hospital of Xiangtan City, Xiangtan City, Hunan Province, 411100, People’s Republic of ChinaCorrespondence: Shunxin ZhuClinical Laboratory, The Maternity & Child Health Care Hospital of Xiangtan City, Xiangtan City, Hunan Province, 411100, People’s Republic of ChinaTel +86- 18975221633Email zhushunxin349@126.comBackground: Bacterial, viral, and bacterial and viral co-infections generally lead to inflammatory-related diseases. The aim of this study is to assess the clinical diagnostic values of serum amyloid A (SAA), procalcitonin (PCT), C-reactive protein (CRP), and interleukin (IL)-6 in children with bacterial, viral, or co-infections.Methods: A total of 181 children with infection symptoms (bacterial infection (Bac group), n = 46; viral infection (Vir group), n = 7; co-infections (Bac + Vir group), n = 128) were enrolled in our hospital from December 2019 to April 2020. Meanwhile, 42 healthy children without any infections were used as the controls. Venous blood samples were collected and the levels of serum SAA, PCT, CRP, and IL-6 were determined by immunoluminometric assay under an IMMAGE® analyzer. The diagnostic values of these biomarkers were assessed using the receiver operating characteristic (ROC) curves.Results: The results indicated that IL-6 level was increased in three infection groups compared to the controls. Both SAA and CRP were significantly elevated in Vir and Bac + Vir groups. High level of PCT was observed in Bac and Bac + Vir goups. In addition, PCT (0.9281, 95% CI = 0.8645– 0.9916) alone is an effective method for identifying bacterial infections. SAA in combination with CRP may distinguish co-infection from bacterial infection. Simultan

Cyber Physical Systems (CPS) are characterized by their ability to integrate the physical and information or cyber worlds. Their deployment in critical infrastructure have demonstrated a potential to transform the world. However, harnessing this potential is limited by their critical nature and the far reaching effects of cyber attacks on human, infrastructure and the environment. An attraction for cyber concerns in CPS rises from the process of sending information from sensors to actuators over the wireless communication medium, thereby widening the attack surface. Traditionally, CPS security has been investigated from the perspective of preventing intruders from gaining access to the system using cryptography and other access control techniques. Most research work have therefore focused on the detection of attacks in CPS. However, in a world of increasing adversaries, it is becoming more difficult to totally prevent CPS from adversarial attacks, hence the need to focus on making CPS resilient. Resilient CPS are designed to withstand disruptions and remain functional despite the operation of adversaries. One of the dominant methodologies explored for building resilient CPS is dependent on machine learning (ML) algorithms. However, rising from recent research in adversarial ML, we posit that ML algorithms for securing CPS must themselves be resilient. This paper is therefore aimed at comprehensively surveying the interactions between resilient CPS using ML and resilient ML when applied in CPS. The paper concludes with a number of research trends and promising future research directions. Furthermore, with this paper, readers can have a thorough understanding of recent advances on ML-based security and securing ML for CPS and countermeasures, as well as research trends in this active research area.

In this paper, we propose and analyze an abstract stabilized mixed finite element framework that can be applied to nonlinear incompressible elasticity problems. In the abstract stabilized framework, we prove that any mixed finite element method that satisfies the discrete inf-sup condition can be modified so that it is stable and optimal convergent as long as the mixed continuous problem is stable. Furthermore, we apply the abstract stabilized framework to nonlinear incompressible elasticity problems and present numerical experiments to verify the theoretical results.

Chunmei Liu,1,2 Juan Yang,1,2 Han Wu,1,2 Jun Li31Department of Pathology, Luohe Central Hospital, Luohe 462000, People’s Republic of China; 2Department of Pathology, The First Affiliated Hospital of Luohe Medical College, Luohe 462000, People’s Republic of China; 3Nursing Department, Xiangya Hospital, Central South University, Changsha 410078, People’s Republic of ChinaBackground: Upregulation of PSME3 and its oncogenic roles have been reported in colon cancer recently. However, the underlying mechanism of PSME3 upregulation remains unknown. Here, we explored the expression of PSME3 and subsequently uncovered its mechanism in colon cancer.Materials and methods: The expression of PSME3 was analyzed by using online databases, Oncomine and UALCAN. qPCR was carried out to detect the expression of PSME3 in collected colon cancer tissues and cell lines. Moreover, the promoter methylation and the hnRNA level of PSME3 were also analyzed by online database and qPCR, respectively. The candidate miRNAs targeting PSME3 were predicted by Starbase 3.0 and validated by luciferase reporter system. CCK-8, plate colon formation, and Edu incorporation were applied to study the functions of miRNA in colon cancer. The expression of miRNA and its correlation with PSME3 were detected in colon cancer tissues.Results: Oncomine and UALCAN data indicate PSME3 is obviously upregulated in colon cancer tissue samples which is further confirmed in collected colon cancer tissues and cells by qPCR. No significant difference in methylation status promoter of PSME3 was observed between colon and colon cancer tissues. The hnRNA level of PSME3 was comparable between colon epithelial cell and colon cancer cells. miR-585-3p is predicted to directly target PSME3 and is validated by luciferase reporter assay. Then, miR-585-3p downregulation is confirmed and miR-585-3p restoration can suppress cell growth and proliferation by inhibiting PSME3 in colon cancer indicating by CCK-8

The electronic properties of rubrene films exposed to oxygen have been studied by photoemission and x-ray absorption spectroscopies. Oxygen incorporation causes the highest occupied molecular orbital of rubrene to shift to a ∼1.0 eV deep level due to chemical bonds formed by the oxygen atoms with the carbon atoms within the tetracene backbone of rubrene molecules. Deformation of the molecular backbone induced by the C–O bonds destroys the delocalized nature of the molecular orbitals. The oxidized rubrene molecules in a single crystal are proposed to act as point defects that disturb the long-range periodicity and produce localized acceptor states.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2005., Includes bibliographical references (p. 143-148)., (cont.) TCP timeout backoff and MAC layer retransmissions, are studied in detail. The results show that the system performance is a balance of idle slots and collisions at the MAC layer, and a tradeoff between packet loss probability and round trip time at the transport layer. Finally, we consider the optimal scheduling problem with window service constraints. Optimal policies that minimize the average response time of jobs are derived and the results show that both the job lengths and the window sizes are essential to the optimal policy., Modern data networks are heterogeneous in that they often employ a variety of link technologies, such as wireline, optical, satellite and wireless links. As a result, Internet protocols, such as Transmission Control Protocol (TCP), that were designed for wireline networks, perform poorly when used over heterogeneous networks. This is particularly the case for satellite and wireless networks which are often characterized by high bandwidth-delay product and high link loss probability. This thesis examines the performance of TCP in the context of heterogeneous networks, particularly focusing on interactions between protocols across different layers of the protocol stack. First, we provide an analytical framework to study the interaction between TCP and link layer retransmission protocols (ARQ). The system is modelled as a Markov chain with reward functions, and detailed queueing models are developed for the link layer ARQ. The analysis shows that in most cases implementing ARQ can achieve significant improvement in system throughput. Moreover, by proper choice of protocols parameters, such as the packet size and the number of transmission attempts per packet, significant performance improvement can be obtained. We then investigate the interaction between TCP at the transport layer and ALOHA at the MAC layer. Two equations are derived to express the system performance in terms of various system and protocol parameters, which show that the maximum possible system throughput is 1/e. A sufficient and necessary condition to achieve this throughput is also presented, and the optimal MAC layer transmission probability at which the system achieves its highest throughput is given. Furthermore, the impact of other system and protocol parameters, such as, by Chunmei Liu., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2005., Includes bibliographical references (p. 143-148)., (cont.) TCP timeout backoff and MAC layer retransmissions, are studied in detail. The results show that the system performance is a balance of idle slots and collisions at the MAC layer, and a tradeoff between packet loss probability and round trip time at the transport layer. Finally, we consider the optimal scheduling problem with window service constraints. Optimal policies that minimize the average response time of jobs are derived and the results show that both the job lengths and the window sizes are essential to the optimal policy., Modern data networks are heterogeneous in that they often employ a variety of link technologies, such as wireline, optical, satellite and wireless links. As a result, Internet protocols, such as Transmission Control Protocol (TCP), that were designed for wireline networks, perform poorly when used over heterogeneous networks. This is particularly the case for satellite and wireless networks which are often characterized by high bandwidth-delay product and high link loss probability. This thesis examines the performance of TCP in the context of heterogeneous networks, particularly focusing on interactions between protocols across different layers of the protocol stack. First, we provide an analytical framework to study the interaction between TCP and link layer retransmission protocols (ARQ). The system is modelled as a Markov chain with reward functions, and detailed queueing models are developed for the link layer ARQ. The analysis shows that in most cases implementing ARQ can achieve significant improvement in system throughput. Moreover, by proper choice of protocols parameters, such as the packet size and the number of transmission attempts per packet, significant performance improvement can be obtained. We then investigate the interaction between TCP at the transport layer and ALOHA at the MAC layer. Two equations are derived to express the system performance in terms of various system and protocol parameters, which show that the maximum possible system throughput is 1/e. A sufficient and necessary condition to achieve this throughput is also presented, and the optimal MAC layer transmission probability at which the system achieves its highest throughput is given. Furthermore, the impact of other system and protocol parameters, such as, by Chunmei Liu., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2005., Includes bibliographical references (p. 143-148)., (cont.) TCP timeout backoff and MAC layer retransmissions, are studied in detail. The results show that the system performance is a balance of idle slots and collisions at the MAC layer, and a tradeoff between packet loss probability and round trip time at the transport layer. Finally, we consider the optimal scheduling problem with window service constraints. Optimal policies that minimize the average response time of jobs are derived and the results show that both the job lengths and the window sizes are essential to the optimal policy., Modern data networks are heterogeneous in that they often employ a variety of link technologies, such as wireline, optical, satellite and wireless links. As a result, Internet protocols, such as Transmission Control Protocol (TCP), that were designed for wireline networks, perform poorly when used over heterogeneous networks. This is particularly the case for satellite and wireless networks which are often characterized by high bandwidth-delay product and high link loss probability. This thesis examines the performance of TCP in the context of heterogeneous networks, particularly focusing on interactions between protocols across different layers of the protocol stack. First, we provide an analytical framework to study the interaction between TCP and link layer retransmission protocols (ARQ). The system is modelled as a Markov chain with reward functions, and detailed queueing models are developed for the link layer ARQ. The analysis shows that in most cases implementing ARQ can achieve significant improvement in system throughput. Moreover, by proper choice of protocols parameters, such as the packet size and the number of transmission attempts per packet, significant performance improvement can be obtained. We then investigate the interaction between TCP at the transport layer and ALOHA at the MAC layer. Two equations are derived to express the system performance in terms of various system and protocol parameters, which show that the maximum possible system throughput is 1/e. A sufficient and necessary condition to achieve this throughput is also presented, and the optimal MAC layer transmission probability at which the system achieves its highest throughput is given. Furthermore, the impact of other system and protocol parameters, such as, by Chunmei Liu., Ph.D.