Hierarchical Resource Management Framework and Multi-hop Task Scheduling Decision for Resource-Constrained VEC Networks

Xi Hu,Yicheng Zhao,Yang Huang,Chen Zhu,Jun Yao,Nana Fang 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.11

In urban vehicular edge computing (VEC) environments, one edge server always serves many task requests in its coverage which results in the resource-constrained problem. To resolve the problem and improve system utilization, we first design a general hierarchical resource management framework based on typical VEC network structures. Following the framework, a specific interacting protocol is also designed for our decision algorithm. Secondly, a greedy bidding-based multi-hop task scheduling decision algorithm is proposed to realize effective task scheduling in resource-constrained VEC environments. In this algorithm, the goal of maximizing system utility is modeled as an optimization problem with the constraints of task deadlines and available computing resources. Then, an auction mechanism named greedy bidding is used to match task requests to edge servers in the case of multiple hops to maximize the system utility. Simulation results show that our proposal can maximize the number of tasks served in resource constrained VEC networks and improve the system utility.

An Efficient and Stable Congestion Control Scheme with Neighbor Feedback for Cluster Wireless Sensor Networks

( Xi Hu ),( Wei Guo ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.9

Congestion control in Cluster Wireless Sensor Networks (CWSNs) has drawn widespread attention and research interests. The increasing number of nodes and scale of networks cause more complex congestion control and management. Active Queue Management (AQM) is one of the major congestion control approaches in CWSNs, and Random Early Detection (RED) algorithm is commonly used to achieve high utilization in AQM. However, traditional RED algorithm depends exclusively on source-side control, which is insufficient to maintain efficiency and state stability. Specifically, when congestion occurs, deficiency of feedback will hinder the instability of the system. In this paper, we adopt the Additive-Increase Multiplicative-Decrease (AIMD) adjustment scheme and propose an improved RED algorithm by using neighbor feedback and scheduling scheme. The congestion control model is presented, which is a linear system with a non-linear feedback, and modeled by Lur`e type system. In the context of delayed Lur`e dynamical network, we adopt the concept of cluster synchronization and show that the congestion controlled system is able to achieve cluster synchronization. Sufficient conditions are derived by applying Lyapunov-Krasovskii functionals. Numerical examples are investigated to validate the effectiveness of the congestion control algorithm and the stability of the network.

Renal-Clearable Hollow Bismuth Subcarbonate Nanotubes for Tumor Targeted Computed Tomography Imaging and Chemoradiotherapy

Hu, Xi,Sun, Jihong,Li, Fangyuan,Li, Ruiqing,Wu, Jiahe,He, Jie,Wang, Nan,Liu, Jianan,Wang, Shuaifei,Zhou, Fei,Sun, Xiaolian,Kim, Dokyoon,Hyeon, Taeghwan,Ling, Daishun American Chemical Society 2018 Nano letters Vol.18 No.2

<P>Although metallic nanomaterials with high X-ray attenuation coefficients have been widely used as X-ray computed tomography (CT) contrast agents, their intrinsically poor biodegradability requires them to be cleared from the body to avoid any potential toxicity. On the other hand, extremely small-sized nanomaterials with outstanding renal clearance properties are not much effective for tumor targeting because of their too rapid clearance in vivo. To overcome this dilemma, here we report on the hollow bismuth subcarbonate nanotubes (BNTs) assembled from renal-clearable ultrasmall bismuth subcarbonate nanoclusters for tumor-targeted imaging and chemoradiotherapy. The BNTs could be targeted to tumors with high efficiency and exhibit a high CT contrast effect. Moreover, simultaneous radio- and chemotherapy using drug-loaded BNTs could significantly suppress tumor volumes, highlighting their potential application in CT imaging-guided therapy. Importantly, the elongated nanotubes could be disassembled into isolated small nanoclusters in the acidic tumor microenvironment, accelerating the payload release and kidney excretion. Such body clearable CT contrast agent with high imaging performance and multiple therapeutic functions shall have a substantial potential for biomedical applications.</P>

Accurate Measurement of Agatston Score Using kVp-Independent Reconstruction Algorithm for Ultra-High-Pitch Sn150 kVp CT

Hu Xi,Tao Xinwei,Zhang Yueqiao,Niu Zhongfeng,Zhang Yong,Allmendinger Thomas,Kuang Yu,Chen Bin 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.11

Objective: To investigate the accuracy of the Agatston score obtained with the ultra-high-pitch (UHP) acquisition mode using tin-filter spectral shaping (Sn150 kVp) and a kVp-independent reconstruction algorithm to reduce the radiation dose. Materials and Methods: This prospective study included 114 patients (mean ± standard deviation, 60.3 ± 9.8 years; 74 male) who underwent a standard 120 kVp scan and an additional UHP Sn150 kVp scan for coronary artery calcification scoring (CACS). These two datasets were reconstructed using a standard reconstruction algorithm (120 kVp + Qr36d, protocol A; Sn150 kVp + Qr36d, protocol B). In addition, the Sn150 kVp dataset was reconstructed using a kVp-independent reconstruction algorithm (Sn150 kVp + Sa36d, protocol C). The Agatston scores for protocols A and B, as well as protocols A and C, were compared. The agreement between the scores was assessed using the intraclass correlation coefficient (ICC) and the Bland–Altman plot. The radiation doses for the 120 kVp and UHP Sn150 kVp acquisition modes were also compared. Results: No significant difference was observed in the Agatston score for protocols A (median, 63.05; interquartile range [IQR], 0–232.28) and C (median, 60.25; IQR, 0–195.20) (p = 0.060). The mean difference in the Agatston score for protocols A and C was relatively small (-7.82) and with the limits of agreement from -65.20 to 49.56 (ICC = 0.997). The Agatston score for protocol B (median, 34.85; IQR, 0–120.73) was significantly underestimated compared with that for protocol A (p < 0.001). The UHP Sn150 kVp mode facilitated an effective radiation dose reduction by approximately 30% (0.58 vs. 0.82 mSv, p < 0.001) from that associated with the standard 120 kVp mode. Conclusion: The Agatston scores for CACS with the UHP Sn150 kVp mode with a kVp-independent reconstruction algorithm and the standard 120 kVp demonstrated excellent agreement with a small mean difference and narrow agreement limits. The UHP Sn150 kVp mode allowed a significant reduction in the radiation dose.

PIK3R3 regulates PPARα expression to stimulate fatty acid β-oxidation and decrease hepatosteatosis

Xi Yang,Yinjia Fu,Fuqing Hu,Xuelai Luo,Junbo Hu,Guihua Wang 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Phosphatidylinositol 3-kinase (PI3K) signaling plays an important role in the regulation of cellular lipid metabolism and non-alcoholic fatty liver disease (NAFLD). However, little is known about the role of the regulatory subunits of PI3K in lipid metabolism and NAFLD. In this study, we characterized the functional role of PIK3R3 in fasting-induced hepatic lipid metabolism. In this study, we showed that the overexpression of PIK3R3 promoted hepatic fatty acid oxidation via PIK3R3-induced expression of PPARα, thus improving the fatty liver phenotype in high-fat diet (HFD)-induced mice. By contrast, hepatic PIK3R3 knockout in normal mice led to increased hepatic TG levels. Our study also showed that PIK3R3-induced expression of PPARα was dependent on HNF4α. The novel PIK3R3-HNF4α-PPARα signaling axis plays a significant role in hepatic lipid metabolism. As the activation of PIK3R3 decreased hepatosteatosis, PIK3R3 can be considered a promising novel target for developing NAFLD and metabolic syndrome therapies.

Relationship between the methylenetetrahydrofolate reductase (MTHFR) rs1801133 SNP and serum homocysteine levels of Zhuang hypertensive patients in the central region of Guangxi

Hu Xi-Jiang,Su Mei-Ru,Cao Bao-Wei,Ou Fa-Bang,Yin Rui-Xing,Luo An-De 대한고혈압학회 2023 Clinical Hypertension Vol.29 No.-

Background The relationship between the methylenetetrahydrofolate reductase (MTHFR) single nucleotide polymorphism (SNP) and serum homocysteine (Hcy) levels or H-type hypertension in different populations is inconsistent. This study aimed to explore the association between the MTHFR rs1801133 SNP and serum Hcy levels of Zhuang hypertensive patients in the central region of Guangxi. Methods A total of 606 Zhuang inpatients with essential hypertension were recruited in our hospital from August 2016 to December 2018. The patients were divided into H-type hypertension (Hcy > 10 μmol/L, n = 528) and non–Htype hypertension (Hcy ≤ 10 μmol/L, n = 78) groups. At the same time, an age- and sex-matched group of 379 subjects with normal physical examination in our hospital were selected as the control group. Blood biochemical measurements and genotyping of the MTHFR rs1801133 SNP were performed. Results The prevalence of H-type hypertension was 87.13%. The levels of serum Hcy in patients with hypertension were higher than those in control group (14.20 ± 5.78 μmol/L vs. 11.97 ± 5.39 μmol/L, P < 0.001), especially in patients with H-type hypertension (15.08 ± 5.65 μmol/L, P < 0.001). The frequencies of TT genotype (22.73%) and T allele (46.21%) in patients with H-type hypertension were significantly higher than those in control group (11.35% and 30.47%, respectively) and non–H-type hypertension group (10.26% and 28.85%, respectively; P < 0.001 for all). Multivariate linear regression analysis showed that serum Hcy levels were significantly correlated with creatinine, lowdensity lipoprotein cholesterol, endogenous creatinine clearance rate, and the MTHFR rs1801133 genotypes in control group, while serum Hcy levels were significantly correlated with creatinine, triglyceride, low-density lipoprotein cholesterol, endogenous creatinine clearance rate, glycosylated hemoglobin, and the MTHFR rs1801133 genotypes in H-type hypertension group (P < 0.05–0.001). Serum Hcy levels in the T allele carriers were higher than those in the T allele noncarriers in both H-type hypertension and control groups. Conclusions There was closely related between the MTHFR rs1801133 SNP and serum Hcy levels in Zhuang patients with H-type hypertension in the central region of Guangxi. The MTHFR SNP may be an important reason for the increase of serum Hcy levels in Zhuang patients with H-type hypertension in this region.

MRI Features of Spinal Epidural Angiolipomas

Su Hu,Chun-hong Hu,Xiao-yun Hu,Xi-ming Wang,Hui Dai,Xiang-ming Fang,Lei Cui 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.5

Objective: To describe the MRI findings in ten patients of spinal epidural angiolipoma for differentiated diagnosis presurgery. Materials and Methods: Ten surgically proved cases of spinal epidural angiolipomas were retrospectively reviewed, and the lesion was classified according to the MR findings. Results: Ten tumors were located in the superior (n = 4), middle (n = 2), or inferior (n = 4) thoracic level. The mass, with the spindle shape, was located in the posterior epidural space and extended parallel to the long axis of the spine. All lesions contained a fat and vascular element. The vascular content, correlating with the presence of hypointense regions on T1-weighted imaging (T1WI) and hyperintense signals on T2-weighted imaging, had marked enhancement. However, there were no flow void signs on MR images. All tumors were divided into two types based on the MR features. In type 1 (n = 3), the mass was predominantly composed of lipomatous tissue (> 50%) and contained only a few small angiomatous regions, which had a trabeculated or mottled appear. In type 2 (n = 7), the mass, however, was predominantly composed of vascular components (> 50%), which presented as large foci in the center of the mass. Conclusion: Most spinal epidural angiolipomas exhibit hyperintensity on T1WI while the hypointense region on the noncontrast T1WI indicates to be vascular, which manifests an obvious enhancement with gadolinium administration.

Analytic Investigation on the Threshold Voltage of Fully-Depleted Surrounding-Gate Metal-Oxide-Semiconductor Field-Effect Transistors

Guang-Xi Hu,Ran Liu,Ting-Ao Tang,Ling-Li Wang 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.6

Analytic solutions for the surrounding-gate (SG) metal-oxide-semiconductor field-effect transistor (MOSFET) are obtained by solving Poisson's equation. The analytic expressions for the electric potential and the threshold voltage are obtained by taking into account the short-channel effects. Our analytic results fit with other numerical and simulated results quite well. The analytic expressions will be of great help in ultralarge-scale integrated-circuit (ULSI) design. Analytic solutions for the surrounding-gate (SG) metal-oxide-semiconductor field-effect transistor (MOSFET) are obtained by solving Poisson's equation. The analytic expressions for the electric potential and the threshold voltage are obtained by taking into account the short-channel effects. Our analytic results fit with other numerical and simulated results quite well. The analytic expressions will be of great help in ultralarge-scale integrated-circuit (ULSI) design.

중국 현대 작곡가 탄둔의 전통음악 요소 활용 연구

호시(Xi Hu),안성희(Sung-Hie Ahn) 한국콘텐츠학회 2022 한국콘텐츠학회논문지 Vol.22 No.6

전 세계가 글로벌화됨에 따라 사람들의 학문과 문화예술의 모습은 서로에게 영향을 주고 있다. 다원화된 예술의 형식은 전통문화의 순수성과 정통성의 틀을 깨트렸다. 그러나 이러한 현상 속에서도 자국 전통문화를 보존하고 계승하는 것은 문화예술의 발전에 간과해서는 안 되는 과제가 되었다. 탄둔은 중국 현대 음악의 대표적 인물로서 중국 음악 발전에 중요한 시사점을 주었으며, 과감하고 자유로운 창작 이념과 작품의 개성, 그리고 중국 전통음악을 현대 작품에 녹여내 국제적으로 주목받고 있는 현존하는 인물이다. 또한 전통과 현대, 동양과 서양의 경계선을 무너트리고 다원적 문화를 하나로 융합시켰다는 평가를 받고 있다. 본 연구는 탄둔의 작품을 통해 중국 문화의 계승 방법을 모색하고 중국 음악의 미래 발전의 방법을 모색하는 것에 그 목적이 있다. 따라서 탄둔 작품의 분석을 통해 오개닉 음악, 불교문화, 무속 신앙, 그리고 민요와 희극 네 가지 전통적 음악 요소를 살펴볼 것이다. 본 연구는 작곡가 탄둔이 중국 전통문화를 현대 작품에서 어떻게 완벽하게 융합시켰는지를 연구하였고, 또한 세계적으로 다원화된 오늘날 자국 문화의 현대성과 공존하기 위한 시사점을 제시하였다. In this era of globalization, peoples knowledge and cultural aesthetics are strongly influenced by the cultures of different countries, and diversified art forms have broken the traditional art framework, so how to stick to the essence of the countrys traditional culture and make it inherited has became an important issue that cannot be ignored in the development of music today. Tan Dun, as one of the representative figures of Chinese contemporary music, has brought important inspirations to the development of Chinese music. With bold and free conceptions, innovative personality, unique Chinese tradition and international perspective. With a spirit of breaking down the barriers between tradition and modernity, East and West, and a concept of integrating multiple cultures into one, he has become a unique figure in the world of music. As researchers in composition, not only do we take on the responsibility of passing on Chinese culture, but we also need to explore the future development direction of Chinese music. Therefore, this paper takes Tan Duns four traditional musical elements of organic music, Buddhist culture, witchcraft beliefs, folk songs and opera in his works and examines how Tan Dun perfectly blends traditional Chinese music culture with contemporary music language. And explore how the domestic traditional culture co-exists with modernity in todays diverse world.

Some Physical Properties of a Surrounding-Gate MOSFET with Undoped Body

Guang-Xi Hu,Ting-Ao Tang 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.2I

A kind of Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET) with a surrounding gate is presented. Some physical properties of the MOSFET are obtained by solving Poisson’s equation analytically. We propose a new criteria for the threshold voltage, and the threshold voltage is obtained in due course. The threshold voltage of a surrounding-gate nMOSFET is influenced by the thickness of the oxide and the radius of the cylinder. It’s also influenced by the work function difference between the gate electrode and intrinsic silicon. A MOSFET with a thinner oxide or a smaller radius will have a higher threshold voltage. We can obtain a desirable threshold voltage by choosing the right material for the gate and the right size for the MOSFET.