Interference-Aware Channel Assignment Algorithm in D2D overlaying Cellular Networks

( Liqun Zhao ),( Hongpeng Wang ),( Xiaoxiong Zhong ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.4

Device-to-Device (D2D) communications can provide proximity based services in the future 5G cellular networks. It allows short range communication in a limited area with the advantages of power saving, high data rate and traffic offloading. However, D2D communications may reuse the licensed channels with cellular communications and potentially result in critical interferences to nearby devices. To control the interference and improve network throughput in overlaid D2D cellular networks, a novel channel assignment approach is proposed in this paper. First, we characterize the performance of devices by using Poisson point process model. Then, we convert the throughput maximization problem into an optimal spectrum allocation problem with signal to interference plus noise ratio constraints and solve it, i.e., assigning appropriate fractions of channels to cellular communications and D2D communications. In order to mitigate the interferences between D2D devices, a cluster-based multi-channel assignment algorithm is proposed. The algorithm first cluster D2D communications into clusters to reduce the problem scale. After that, a multi-channel assignment algorithm is proposed to mitigate critical interferences among nearby devices for each D2D cluster individually. The simulation analysis conforms that the proposed algorithm can greatly increase system throughput.

Interference Aware Channel Assignment Algorithm for D2D Multicast Underlying Cellular Networks

Liqun. Zhao,Lingmei Ren,Li Li 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.8

Device-to-device (D2D) multicast has become a promising technology to provide specific services within a small geographical region with a high data rate, low delay and low energy consumption. However, D2D multicast communications are allowed to reuse the same channels with cellular uplinks and result in mutual interference in a cell. In this paper, an intelligent channel assignment algorithm is designed in D2D underlaid cellular networks with the target of maximizing network throughput. We first model the channel assignment problem to be a throughput maximizing problem which is NP-hard. To solve the problem in a feasible way, a novel channel assignment algorithm is proposed. The key idea is to find the appropriate cellular communications and D2D multicast groups to share a channel without causing critical interference, i.e., finding a channel for a D2D multicast group which generates the least interference to network based on current channel assignment status. In order to show the efficacy and effectiveness of our proposed algorithm, a novel search algorithm is proposed to find the near-optimal solution as the baseline for comparisons. Simulation results show that the proposed algorithm improves the network throughput.

Fault Location for Incomplete-Journey Double-Circuit Transmission Lines on Same Tower Based on Identification of Fault Branch

Wang, Shoupeng,Zhao, Dongmei,Shang, Liqun The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.12 No.5

This paper analyses the characteristics of incomplete-journey double-circuit transmission lines on the same tower formed by single-circuit lines and double-circuit lines, and then presents a fault location algorithm based on identification of fault branch. With the relationship between the three-phase system and the double-circuit line system, a phase-mode transformation matrix for double-circuit lines can be derived. Based on the derived matrix, the double-circuit lines with faults can be decoupled, and then the fault location for an incomplete-journey double-circuit line is achieved by using modal components in the mode domain. The algorithm is divided into two steps. Firstly, the fault branch is identified by comparing the relationships of voltage amplitudes at the bonding point. Then the fault location, on the basis of the identification result, is calculated by using a two-terminal method, and only the fault distance of the actual fault branch can be obtained. There is no limit on synchronization of each terminal sampling data. The results of ATP-EMTP simulation show that the proposed algorithm can be applied within the entire line and can accurately locate faults in different fault types, fault resistances, and fault distances.

Fault Location for Incomplete-Journey Double-Circuit Transmission Lines on Same Tower Based on Identification of Fault Branch

Shoupeng Wang,Dongmei Zhao,Liqun Shang 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.5

This paper analyses the characteristics of incomplete-journey double-circuit transmission lines on the same tower formed by single-circuit lines and double-circuit lines, and then presents a fault location algorithm based on identification of fault branch. With the relationship between the three-phase system and the double-circuit line system, a phase-mode transformation matrix for doublecircuit lines can be derived. Based on the derived matrix, the double-circuit lines with faults can be decoupled, and then the fault location for an incomplete-journey double-circuit line is achieved by using modal components in the mode domain. The algorithm is divided into two steps. Firstly, the fault branch is identified by comparing the relationships of voltage amplitudes at the bonding point. Then the fault location, on the basis of the identification result, is calculated by using a two-terminal method, and only the fault distance of the actual fault branch can be obtained. There is no limit on synchronization of each terminal sampling data. The results of ATP-EMTP simulation show that the proposed algorithm can be applied within the entire line and can accurately locate faults in different fault types, fault resistances, and fault distances.

Inhalation of panaxadiol alleviates lung infl ammation via inhibiting TNFA/ TNFAR and IL7/IL7R signaling between macrophages and epithelial cells

Yifan Wang,Hao Wei,Zhen Song,Liqun Jiang,Mi Zhang,Xiao Lu,Wei Li,Yuqing Zhao,Lei Wu,Shuxian Li,Huijuan Shen,Qiang Shu,Yicheng Xie 고려인삼학회 2024 Journal of Ginseng Research Vol.48 No.1

Background: Lung inflammation occurs in many lung diseases, but has limited effective therapeutics. Ginseng andits derivatives have anti-inflammatory effects, but their unstable physicochemical and metabolic propertieshinder their application in the treatment. Panaxadiol (PD) is a stable saponin among ginsenosides. Inhalationadministration may solve these issues, and the specific mechanism of action needs to be studied. Methods: A mouse model of lung inflammation induced by lipopolysaccharide (LPS), an in vitro macrophageinflammation model, and a coculture model of epithelial cells and macrophages were used to study the effectsand mechanisms of inhalation delivery of PD. Pathology and molecular assessments were used to evaluate efficacy. Transcriptome sequencing was used to screen the mechanism and target. Finally, the efficacy andmechanism were verified in a human BALF cell model. Results: Inhaled PD reduced LPS-induced lung inflammation in mice in a dose-dependent manner, includinginflammatory cell infiltration, lung tissue pathology, and inflammatory factor expression. Meanwhile, the dose ofinhalation was much lower than that of intragastric administration under the same therapeutic effect, which maybe related to its higher bioavailability and superior pharmacokinetic parameters. Using transcriptome analysisand verification by a coculture model of macrophage and epithelial cells, we found that PD may act by inhibitingTNFA/TNFAR and IL7/IL7R signaling to reduce macrophage inflammatory factor-induced epithelial apoptosisand promote proliferation. Conclusion: PD inhalation alleviates lung inflammation and pathology by inhibiting TNFA/TNFAR and IL7/IL7Rsignaling between macrophages and epithelial cells. PD may be a novel drug for the clinical treatment of lunginflammation.

Protective Effect of Nitric Oxide against Oxidative Damage in Arabidopsis Leaves under Ultraviolet-B Irradiation

Lingang Zhang,Shuo Zhou,Yi Xuan,Miao Sun,Liqun Zhao 한국식물학회 2009 Journal of Plant Biology Vol.52 No.2

Nitric oxide (NO) is a key molecule involved in many physiological processes. To characterize its roles in the tolerance of Arabidopsis thaliana to ultraviolet-B (UV-B), we investigated the effect of a reduced endogenous NO level on oxidative damage to wild-type and mutant (Atnoa1) plants. Under irradiation, hydrogen peroxide was accumulated more in mutant leaves than in the wild type. However, the amounts of UV-B-absorbing compounds (flavonoids and anthocyanin) and the activities of two antioxidant enzymes—catalase (CAT, EC 1.11.1.6) and ascorbate peroxidase (APX, EC 1.11.1.11)—were lower in leaves of the former. Supplementing with sodium nitroprusside, an NO donor, could alleviate the oxidative damage to mutant leaves by increasing flavonoid and anthocyanin contents and enzyme activities. In comparison, Nw ? nitro ? l ? arginine, an inhibitor of nitric oxide synthase, had the opposite effects on oxidation resistance in wild-type leaves. All these results suggest that nitric oxide acts as a signal for an active oxygen-scavenging system that protects plants from oxidative stress induced by UV-B irradiation.

Trapidil determines the fate of RHF rats through inhibition of ER stress

Yilin Wang,Yu Wang,Chengxi Wei,Quan Wan,Zhifei Fan,Liying Xuan,Wanru Geng,Liqun Shao,Jie Long,Junyi Gu,Ming Zhao 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.4

Pulmonary arterial hypertension is a fatal disease,especially when it causes right heart failure (RHF). However, it is difficult to treat. It has been reported thattrapidil (Tra) can improve the redox balance and cardiacconditions. In this study, we investigated the effect of Tra onRHF induced by monocrotaline (MCT) in rats. Male Wistarrats were treated with MCT or Tra. Treatment lasted 28 days,then rats were euthanized after echocardiography and catheterization. Subsequently, lungs and right ventricular myocardiawere evaluated by hematoxylin and eosin, Masson,and TUNEL staining. Protein expression was detected bywestern blotting. We found remarkably expanded rightventricle end-diastolic volume, decreased partial pressureof oxygen (PaO2), increased partial pressure of carbondioxide (PaCO2), right ventricular systolic pressure, meanpulmonary arterial pressure, lung/body weight, and liver/body weight in the RHF rat group, as well as increases inthe apoptosis rate and the expression of endoplasmic reticulumstress (ERS)-related proteins. However, these changes were significantly inhibited by Tra. Our data suggested thatinhibition of ERS is essential for improving RHF, and thattherapeutic intervention of Tra in RHF rats works by reducingERS.