A Novel Antenna Based on Hexagonal Shaped Left-Handed Materials

Tong Huang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.5

In this paper, the design and analysis of a hexagonal left-handed material is presented, which is based on the analysis of the structural parameters. The effective permittivity and the effective permeability of the designed hexagonal left-handed material are simultaneously negative in the range from 7.4GHz to 7.9GHz. According to the empirical formula of the microstrip antenna, a conventional microstrip antenna is designed. The different combinations of the hexagonal left-handed materials and the conventional microstrip antenna are analyzed in HFSS software. The novel antenna is proposed based on the analysis of the combinations. The simulation results show that the gain of the antenna increased by 0.51dB, and the half power beam width decreased by 3°. Besides, the bandwidth of the novel antenna is 140MHz wider than that of the conventional microstrip antenna. It is concluded that the performance of microstrip antenna can be improved by using left-handed materials.

Sequence Impedance Modeling and Frequency Characteristic Analysis of MMC-based HVDC

Tong Huang,Xin Chen,Guanghui Li,Guoqing He 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Modular multilevel converter (MMC) has emerged as a preferred technology for high-voltage dc (HVDC) transmission, while many HVDC-MMC projects have been reported resonance problems. The existing researches show that stability of a HVDC-grid system is decided by both the sequence impedance characteristic of HVDC-MMC and power grid, and due to coupling effect, the power grid impedance will also impact the HVDCMMC impedance characteristic. Multi-harmonic linearization method will be adopted in this paper to develop a HVDC-MMC analytical sequence impedance model. Then the developed model is used to illustrate the effect of the power control loop as well as the bandwidth of other controllers on HVDC-MMC impedance characteristic. Finally, based on the sequence impedance model considering coupling effect, the influence of HVDC-MMC bandwidth on the system stability will be analyzed as well.

Study on the measurement accuracy of circular transmission line model for low-resistance Ohmic contacts on III-V wide band-gap semiconductors

Tong Liu,Rong Huang,Fangsen Li,Zengli Huang,Jian Zhang,Jianping Liu,Liqun Zhang,Shuming Zhang,An Dingsun,Hui Yang 한국물리학회 2018 Current Applied Physics Vol.18 No.7

The accuracy and error propagation for determining the low specific contact resistance of Ohmic contacts on IIIV wide band-gap semiconductors based on the circular transmission line model have been analyzed and the validity of this method is discussed in detail. The accuracy is more susceptible to the factors including data fitting method, electrical measurement technique and contact area correction. By using the equations of the original circular transmission line model to extract the fitting parameters, the calculation accuracy is much improved and the inapplicability of the linear least-square fitting is prevented. To further improve the accuracy, a four-probe current-voltage measurement technique was adopted to reduce the parasitic series resistances and the uncertainty bound, especially for the Ohmic contact with low sheet resistance of the semiconductor. Moreover, we have studied the size effect of contact pads of patterns and demonstrated that contact area correction is necessary for the semiconductor with high sheet resistance. A comprehensive error analysis is also performed to fully understand all the impact factors on this advanced method of specific contact resistance measurement, which is benefit for device performance evaluation and failure analysis.

Fast Continuous Collision Detection using Graphics Hardware

Tong-Lang Huang,Min Tang,Ruo-Feng Tong,Jin-Xiang Dong (사)한국CDE학회 2005 한국CAD/CAM학회 국제학술발표 논문집 Vol.2005 No.8

Design and Analysis of Metamaterial Antenna Using Double Square Rings

Tong Huang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.7

In this paper, the design and the analysis of the double square ring (DSR) metamaterial is presented, which is based on the equivalent circuit theory and the analysis of the distribution of the electromagnetic field. Based on the retrieval algorithm, the effect of the structural parameters on the effective permittivity and the effective permeability are proposed. The effective permittivity and the effective permeability of the designed DSR metamaterial are simultaneously negative in the range from 4.8GHz to 5.65GHz. A conventional microstrip antenna is designed as comparison, and the analysis of the microstrip antenna is not written in this paper for brevity. The superstrate is composed of an 44 array of the DSR metamaterial, and the novel antenna is consist of the conventional microstrip antenna and the superstrate. The effect of the distance between the superstrate and the antenna are simulated by HFSS software, and the novel antenna is proposed according to the analysis of the distance. The simulation results show that the gain of the novel antenna increased by 1.1dB, and the half power beam width decreased by 40.9°. Therefore, it is concluded that the performance of microstrip antenna can be improved by using DSR metamaterials.

Decreased Expression of LKB1 Correlates with Poor Prognosis in Hepatocellular Carcinoma Patients Undergoing Hepatectomy

Huang, Yue-Han,Chen, Zhen-Kun,Huang, Ka-Te,Li, Peng,He, Bin,Guo, Xu,Zhong, Jun-Qiao,Zhang, Qi-Yu,Shi, Hong-Qi,Song, Qi-Tong,Yu, Zheng-Ping,Shan, Yun-Feng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Aim: To study any correlation of LKB1 expression with prognosis in hepatocellular carcinoma (HCC) cases. Methods: A total of 70 HCC patients and 20 primary intrahepatic stone patients in the first affiliated hospital of Wenzhou Medical College were enrolled in this study. LKB1 expression was detected by immunohistochemistry. Patients were followed-up and prognostic factors were evaluated. Result: LKB1 expression was decreased in the HCC samples. Loss of LKB1 expression in HCC was significantly related to histologic grade (P=0.010), vascular invasion (P=0.025) and TMN stage (P=0.011). Patients showing negative LKB1 expression had a significantly shorter disease-free and overall survival than those with positive expression (P = 0.001, P=0.000, respectively). Multivariate Cox regression analysis indicated that LKB1 expression level was an independent factor of survival (P = 0.033). Conclusion: HCC patients with decreased expression LKB1 have a poor prognosis. The loss of LKB1 expression is correlated with a lower survival rate.

Intravenous patient-controlled analgesia hydromorphone combined with pregabalin for the treatment of postherpetic neuralgia: a multicenter, randomized controlled study

( Ying Huang ),( Chenjie Xu ),( Tao Zeng ),( Zhongming Li ),( Yanzhi Xia ),( Gaojian Tao ),( Tong Zhu ),( Lijuan Lu ),( Jing Li ),( Taiyuan Huang ),( Hongbo Huai ),( Benxiang Ning ),( Chao Ma ),( Xinx 대한통증학회 2021 The Korean Journal of Pain Vol.34 No.2

Background: Postherpetic neuralgia (PHN) is the most common complication of acute herpes zoster. The treatment of PHN remains a challenge for clinical pain management. Despite the effectiveness of anticonvulsants, antidepressants, and lidocaine patches in reducing PHN, many patients still face intractable pain disorders. In this randomized controlled study, we evaluated whether hydromorphone through intravenous patient-controlled analgesia (IV PCA) was effective in relieving PHN. Methods: Patients with PHN were randomly divided into two groups, one group received oral pregabalin with IV normal saline, another group received oral pregabalin with additional IV PCA hydromorphone for two weeks. Efficacy was evaluated at 1, 4, and 12 weeks after the end of the treatments. Results: Two hundred and one patients were followed up for 12 weeks. After treatment, numerical rating scale (NRS) score of patients in the hydromorphone group was significantly lower than that of the control group, and the difference of NRS scores between the two groups was statistically significant at 4 and 12 weeks after treatment. The frequency of breakthrough pain in the hydromorphone group was significantly lower than that in the control group 1 and 4 weeks after treatment. After treatment, the quality of sleep in the hydromorphone group was significantly improved compared with the control group. The most common adverse reactions in the hydromorphone group were dizziness and nausea, with no significant respiratory depression. Conclusions: IV PCA hydromorphone combined with oral pregabalin provides superior pain relief in patients with PHN, which is worthy of clinical application and promotion.

Effects of Cryogenic Deformation on Second-Phase Al2Cu Particles and Mechanical Properties of 2219 Al–Cu Alloy Rings

Jianwu Huang,Youping Yi,Shiquan Huang,Fei Dong,Wanfu Guo,Dengliang Tong,Hailin He 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

2219 Al–Cu alloy transition rings are widely used in launch vehicles. However, the coarse and agglomerated second-phaseAl2Cuparticles significantly deteriorate the mechanical properties and ductility of 2219 Al–Cu alloy rings manufactured bytraditional thermal deformation processes. In this study, cryogenic deformation (− 190 °C) is applied for the manufacturingof 2219 Al–Cu alloy rings to alleviate this problem. The effects on the evolution of second-phase Al2Cuparticles and themechanical properties of the T8-aged samples were examined in comparison with the results of room-temperature (25 °C)and conventional thermal deformation at 480 °C. The results indicate that cryogenic deformation can effectively producehigh-density dislocations and strongly crush coarse particles, promoting the dissolution of Al2Cuparticles and improving theirdistribution in the Al matrix when combined with subsequent solution treatment and rolling processes. As the deformationtemperature was decreased from 480 to −190 °C, the area fraction of the coarse particles was decreased from 1.55 to 0.47%,while their mean size was decreased from 11.8 to 8.3 μm. Correspondingly, the uniformity and density of the precipitatesafter T8 aging were improved. Thus, the mechanical properties of the T8-aged samples were improved with decreasingdeformation temperatures; the average ultimate tensile strength, yield strength, and elongation were increased by 20 MPa,22 MPa, and 3.1% at room temperature.

Associations of Plasma Glucagon Levels with Estimated Glomerular Filtration Rate, Albuminuria and Diabetic Kidney Disease in Patients with Type 2 Diabetes Mellitus

Hua-Xing Huang,Liang-Lan Shen,Hai-Yan Huang,Li-Hua Zhao,Feng Xu,Dong-Mei Zhang,Xiu-Lin Zhang,Tong Chen,Xue-Qin Wang,Yan Xie,Jian-Bin Su 대한당뇨병학회 2021 Diabetes and Metabolism Journal Vol.45 No.6

Background: Type 2 diabetes mellitus (T2DM) is characterized by elevated fasting glucagon and impaired suppression of postprandial glucagon secretion, which may participate in diabetic complications. Therefore, we investigated the associations of plasma glucagon with estimated glomerular filtration rate (eGFR), albuminuria and diabetic kidney disease (DKD) in T2DM patients.Methods: Fasting glucagon and postchallenge glucagon (assessed by area under the glucagon curve [AUCgla]) levels were determined during oral glucose tolerance tests. Patients with an eGFR <60 mL/min/1.73 m2 and/or a urinary albumin-to-creatinine ratio (UACR) ≥30 mg/g who presented with diabetic retinopathy were identified as having DKD.Results: Of the 2,436 recruited patients, fasting glucagon was correlated with eGFR and UACR (r=–0.112 and r=0.157, respectively; P<0.001), and AUCgla was also correlated with eGFR and UACR (r=–0.267 and r=0.234, respectively; P<0.001). Moreover, 31.7% (n=771) presented with DKD; the prevalence of DKD was 27.3%, 27.6%, 32.5%, and 39.2% in the first (Q1), second (Q2), third (Q3), and fourth quartile (Q4) of fasting glucagon, respectively; and the corresponding prevalence for AUCgla was 25.9%, 22.7%, 33.7%, and 44.4%, respectively. Furthermore, after adjusting for other clinical covariates, the adjusted odds ratios (ORs; 95% confidence intervals) for DKD in Q2, Q3, and Q4 versus Q1 of fasting glucagon were 0.946 (0.697 to 1.284), 1.209 (0.895 to 1.634), and 1.521 (1.129 to 2.049), respectively; the corresponding ORs of AUCgla were 0.825 (0.611 to 1.114), 1.323 (0.989 to 1.769), and 2.066 (1.546 to 2.760), respectively. Additionally, when we restricted our analysis in patients with glycosylated hemoglobin <7.0% (n=471), we found fasting glucagon and AUCgla were still independently associated with DKD.Conclusion: Both increased fasting and postchallenge glucagon levels were independently associated with DKD in T2DM patients.

Four Apolipoprotein B gene polymorphisms and the risk for coronary artery disease: a meta-analysis of 47 studies

Dan Xiao,Kaisen Huang,Qingyong Chen,Baotao Huang,Wei Liu,Yong Peng,Mao Chen,Dejia Huang,Tong Zou,Jiefu Yang 한국유전학회 2015 Genes & Genomics Vol.37 No.7

Apolipoprotein B plays a central role in lipoprotein metabolism. Many studies have evaluated the association between Apolipoprotein B gene polymorphisms (XbaI, EcoRI, SpIns/Del, MspI) and the risk for coronary artery disease and myocardial infarction. However, the results remain inconsistent, particularly among different populations. To more precisely determine the association between Apolipoprotein B gene polymorphisms and coronary artery disease/myocardial infarction risk, we performed a meta-analysis via a comprehensive search of electronic databases (up to February 1st, 2015), odds ratios (OR) and 95 % confidence intervals were calculated using a fixed or random effect model. A total of 47 studies, with 9411 coronary artery disease/myocardial infarction cases and 9082 controls, were included in this meta-analysis. The combined results revealed significant associations between an increased risk of coronary artery disease/myocardial infarction and EcoRI (AA vs GG: OR 1.511, 95 % confidence interval (CI) 1.098, 2.078) and SpIns/Del (DD vs II: OR 1.331, 95 % CI 1.064, 1.665) alleles in the general population. In a subgroup analysis stratified by ethnicity, the T allele of the XbaI variant was associated with a decreased risk in Caucasians, whereas it was associated with an increased risk among the East Asian population. No significant correlation was detected between the A allele of the MspI variant and the coronary artery disease/myocardial infarction risk in either the general population or any ethnic subgroup. The results of our study suggest that Apolipoprotein B gene polymorphisms may affect the coronary artery disease/myocardial infarction susceptibility and these effects may display notable discrepancies among different populations.