Improved AP Deployment Optimization Scheme Based on Multi-objective Particle Swarm Optimization Algorithm

( Zhengyu Kong ),( Duanpo Wu ),( Xinyu Jin ),( Shuwei Cen ),( Fang Dong ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.4

Deployment of access point (AP) is a problem that must be considered in network planning. However, this problem is usually a NP-hard problem which is difficult to directly reach optimal solution. Thus, improved AP deployment optimization scheme based on swarm intelligence algorithm is proposed to research on this problem. First, the scheme estimates the number of APs. Second, the multi-objective particle swarm optimization (MOPSO) algorithm is used to optimize the location and transmit power of APs. Finally, the greedy algorithm is used to remove the redundant APs. Comparing with multi-objective whale swarm optimization algorithm (MOWOA), particle swarm optimization (PSO) and grey wolf optimization (GWO), the proposed deployment scheme can reduce AP's transmit power and improves energy efficiency under different numbers of users. From the experimental results, the proposed deployment scheme can reduce transmit power about 2%-7% and increase energy efficiency about 2%-25%, comparing with MOWOA. In addition, the proposed deployment scheme can reduce transmit power at most 50% and increase energy efficiency at most 200%, comparing with PSO and GWO.

An Algorithm for Data Aggregation Scheduling with Long-lifetime and Low-latency in Wireless Sensor Networks

Zhengyu Chen,Geng Yang,Lei Chen,Jin Wang 보안공학연구지원센터 2012 International Journal of Future Generation Communi Vol.5 No.4

Input Voltage Range Extension Method for Half-Bridge LLC Converters by Using Magamp Auxiliary Post-Regulator

Jin, Xiaoguang,Lin, Huipin,Xu, Jun,Lu, Zhengyu The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

An improved half-bridge LLC converter with a magamp auxiliary post-regulator is proposed in this paper. The function of the magamp is bypassed when the converter works within the low input-voltage range. Meanwhile, it operates as an auxiliary post-regulator when the input voltage is high. By changing the blocking time of the magamp, the dc gain of the converter can be extended. Hence, the input voltage range of the converter is extended. The realization of proposed topology does not require a complicated circuit. The controller of the magamp can be easily implemented using only passive components, transistors and an OP amp. The generalized operational principle is analyzed and the design criterion for the magamp is presented. Finally, a 25V output, 400W experimental prototype was built and tested for a 160-300V input-voltage range to verify the feasibility of the proposed method.

Input Voltage Range Extension Method for Half-Bridge LLC Converters by Using Magamp Auxiliary Post-Regulator

Xiaoguang Jin,Huipin Lin,Jun Xu,Zhengyu Lu 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

An improved half-bridge LLC converter with a magamp auxiliary post-regulator is proposed in this paper. The function of themagamp is bypassed when the converter works within the low input-voltage range. Meanwhile, it operates as an auxiliarypost-regulator when the input voltage is high. By changing the blocking time of the magamp, the dc gain of the converter can beextended. Hence, the input voltage range of the converter is extended. The realization of proposed topology does not require acomplicated circuit. The controller of the magamp can be easily implemented using only passive components, transistors and anOP amp. The generalized operational principle is analyzed and the design criterion for the magamp is presented. Finally, a 25Voutput, 400W experimental prototype was built and tested for a 160–300V input-voltage range to verify the feasibility of theproposed method.

Anticorrosion and antibiofouling performance of in-situ prepared layered double hydroxide coating modified by sodium pyrithione on aluminum alloy 7075

Wenyuan Jian,Zhengyu Jin,Jing Yang,Guozhe Meng,Hongfang Liu,Hongwei Liu 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.113 No.-

The anticorrosion and antibiofouling of marine engineering equipments have strong demands, especiallyfor antibiofouling. In this work, an in-situ growth layered double hydroxide (LDH) coating on aluminumalloys (AA) 7075 was prepared and then modified by sodium pyrithione (SPT) to increase the anticorrosionand antibiofouling performance. Results indicated that CoAl-LDHs and CoAl-LDHs-SPT coatings hadbeen successfully prepared according to TEM, XRD, XPS, Raman spectra, and SEM analysis results. The(0 1 2) plane of LDHs with a interplanar spacing of 0.26 nm was recognized from TEM images. The contentof SPT in CoAl-LDHs-SPT is 38.79 wt.%. Electrochemical impedance spectroscopy (EIS) and polarizationcurvies demonstrate that the corrosion resistance of AA 7075 was largely improved in the presence ofCoAl-LDHs and CoAl-LDHs-SPT coatings while the anticorrosion performance of CoAl-LDHs-SPT coatingwas better. The corrosion resistance of Co-Al LDHs-SPT coating increased by about two orders of magnitudecompared with the bare AA 7075. The surface analysis results show that only a few Pseudomonasaeruginosa and Spirulina cells attached to the CoAl-LDHs coating surface, and no biofouling cells wereobserved for the CoAl-LDHs-SPT coating. Co-Al LDHs-SPT coating possessed the best anticorrosion andantibiofouling properties due to the presence of SPT compared with the CoAl-LDHs coating.

Effect of Resveratrol on Serum and Liver Lipid Profile and Antioxidant Activity in Hyperlipidemia Rats

Zhu, Lixian,Luo, Xin,Jin, Zhengyu Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.6

The antioxidant activity of resveratrol in cholesterol-fed rats, along with its hypolipidemic effects was determined. Thirty two male Sprague-Dawley (SD) rats were randomly divided into three groups (Control, Res30 and Res70) and fed a hyperlipidemic diet for 4 weeks. Resveratrol was suspended in 0.3% carboxymethyl cellulose (CMC) solution and given to rats of the Res30 and Res70 groups once a day for 4 weeks by oral intubation at a dose of 30 and 70 mg/kg body weight, respectively. The control group received 0.3% CMC solution alone. Resveratrol significantly lowered serum lipid, hepatic cholesterol (TC) and triglyceride (TG) levels compared to the control. Excretion of bile acids was significantly enhanced by resveratrol. The overall potential of the antioxidant system was significantly enhanced by the resveratrol as plasma and hepatic thiobarbituric acid reactive substances (TBARS) levels were lowered while serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities were increased in the cholesterol-fed rats. These findings suggest that resveratrol maintains an antioxidant efficacy as well as its anti-hyperlipidemic effect.

Characterization of ADME gene variation in 21 populations by exome sequencing

Hovelson, Daniel H.,Xue, Zhengyu,Zawistowski, Matthew,Ehm, Margaret G.,Harris, Elizabeth C.,Stocker, Sophie L.,Gross, Annette S.,Jang, In-Jin,Ieiri, Ichiro,Lee, Jong-Eun,Cardon, Lon R.,Chissoe, Stepha Lippincott WilliamsWilkins 2017 PHARMACOGENETICS AND GENOMICS Vol.27 No.3

<▼1><P>Supplemental Digital Content is available in the text.</P></▼1><▼2><P><B>Objective</B></P><P>Proteins involving absorption, distribution, metabolism, and excretion (ADME) play a critical role in drug pharmacokinetics. The type and frequency of genetic variation in the ADME genes differ among populations. The aim of this study was to systematically investigate common and rare ADME coding variation in diverse ethnic populations by exome sequencing.</P><P><B>Materials and methods</B></P><P>Data derived from commercial exome capture arrays and next-generation sequencing were used to characterize coding variation in 298 ADME genes in 251 Northeast Asians and 1181 individuals from the 1000 Genomes Project.</P><P><B>Results</B></P><P>Approximately 75% of the ADME coding sequence was captured at high quality across the joint samples harboring more than 8000 variants, with 49% of individuals carrying at least one ‘knockout’ allele. ADME genes carried 50% more nonsynonymous variation than non-ADME genes (<I>P</I>=8.2×10<SUP>–13</SUP>) and showed significantly greater levels of population differentiation (<I>P</I>=7.6×10<SUP>–11</SUP>). Out of the 2135 variants identified that were predicted to be deleterious, 633 were not on commercially available ADME or general-purpose genotyping arrays. Forty deleterious variants within important ADME genes, with frequencies of at least 2% in at least one population, were identified as candidates for future pharmacogenetic studies.</P><P><B>Conclusion</B></P><P>Exome sequencing was effective in accurately genotyping most ADME variants important for pharmacogenetic research, in addition to identifying rare or potentially de novo coding variants that may be clinically meaningful. Furthermore, as a class, ADME genes are more variable and less sensitive to purifying selection than non-ADME genes.</P></▼2>

Dark-Blood Computed Tomography Angiography Combined With Deep Learning Reconstruction for Cervical Artery Wall Imaging in Takayasu Arteritis

Su Tong,Zhang Zhe,Chen Yu,Wang Yun,Li Yumei,Xu Min,Wang Jian,Li Jing,Tian Xinping,Jin Zhengyu 대한영상의학회 2024 Korean Journal of Radiology Vol.25 No.4

Objective: To evaluate the image quality of novel dark-blood computed tomography angiography (CTA) imaging combined with deep learning reconstruction (DLR) compared to delayed-phase CTA images with hybrid iterative reconstruction (HIR), to visualize the cervical artery wall in patients with Takayasu arteritis (TAK). Materials and Methods: This prospective study continuously recruited 53 patients with TAK (mean age: 33.8 ± 10.2 years; 49 females) between January and July 2022 who underwent head-neck CTA scans. The arterial- and delayed-phase images were reconstructed using HIR and DLR. Subtracted images of the arterial-phase from the delayed-phase were then added to the original delayed-phase using a denoising filter to generate the final-dark-blood images. Qualitative image quality scores and quantitative parameters were obtained and compared among the three groups of images: Delayed-HIR, Dark-blood-HIR, and Dark-blood-DLR. Results: Compared to Delayed-HIR, Dark-blood-HIR images demonstrated higher qualitative scores in terms of vascular wall visualization and diagnostic confidence index (all P < 0.001). These qualitative scores further improved after applying DLR (Dark-blood-DLR compared to Dark-blood-HIR, all P < 0.001). Dark-blood DLR also showed higher scores for overall image noise than Dark-blood-HIR (P < 0.001). In the quantitative analysis, the contrast-to-noise ratio (CNR) values between the vessel wall and lumen for the bilateral common carotid arteries and brachiocephalic trunk were significantly higher on Darkblood- HIR images than on Delayed-HIR images (all P < 0.05). The CNR values were significantly higher for Dark-blood-DLR than for Dark-blood-HIR in all cervical arteries (all P < 0.001). Conclusion: Compared with Delayed-HIR CTA, the dark-blood method combined with DLR improved CTA image quality and enhanced visualization of the cervical artery wall in patients with TAK.