MAPS BETWEEN 3-MANIFOLDS

WANG, SHICHENG TOPOLOGY AND GEOMETRY RESEARCH CENTER 1997 Proceedings of the Topology and Geometry Research Vol.8 No.-

This note gives some questions, results and references in the topic of maps between 3-manifolds.

Robust Visual Inertial Odometry Estimation Based on Adaptive Interactive Multiple Model Algorithm

Lei Wang,Shicheng Xia,Hengliu Xi,Shuangxi Li,Le Wang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.10

In this paper, we focus on the problem of motion tracking in unknown environments using visual and inertial sensors, commonly known as visual-Inertial odometer (VIO) tasks. Currently, there are two main types of estimation methods to achieve VIO estimation, the filter-based method and the optimization-based method. We combine multi-state-constraint Kalman filter (MSCKF) algorithm with interactive multi-model algorithm and propose a novel filter-based VIO method. Compared with the VIO algorithm based on extended Kalman filter (EKF), the MSCKF algorithm has less strict probability assumption and better accuracy and consistency. However, traditional EKF and MSCKF algorithms both adopt a single fixed system model, which is difficult to adapt to complex and changeable application scenarios. To solve this problem, we introduce the adaptive multi-model method into the MSCKF algorithm, and combine the two to build an interactive multi-model MSCKF (IMM-MSCKF) algorithm. In the proposed IMM-MSCKF algorithm, several model sub-filters are designed, and their results are fused by transition probability to obtain the optimal state estimation. The common data set KITTI is used to verify the proposed IMM-MSCKF algorithm. Experiment results show that the proposed novel algorithm has better estimation accuracy and robustness compared with other solutions based on multi-state constraint Kalman filter. The IMM-MSCKF algorithm can achieve long-term, high-precision and consistent real-time VIO tasks.

Improved oral bioavailability of capsaicin via liposomal nanoformulation: preparation, in vitro drug release and pharmacokinetics in rats

Yuan Zhu,Miaomiao Wang,Jiajia Zhang,Wei Peng,Caleb Kesse Firempong,Wenwen Deng,Qilong Wang,Shicheng Wang,Feng Shi,Jiangnan Yu,Ximing Xu,Weiming Zhang 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.4

This study innovatively prepared an effectivecapsaicin-loaded liposome, a nanoformulation with fewerirritants, for oral administration. The in vitro and in vivoproperties of the liposomal encapsulation were investigatedand the potential possibility of oral administration evaluated. The liposomal agent composed of phospholipid, cholesterol,sodium cholate and isopropyl myristate was prepared usingfilm-dispersion method. A level A in vitro–in vivo correlation(IVIVC) was established for the first time, which demonstratedan excellent IVIVC of both formulated and freecapsaicin in oral administration. Physicochemical characterizationsincluding mean particle size, zeta (f) potentialand average encapsulation efficiency of capsaicin-loadedliposome were found to be 52.2 ± 1.3 nm, -41.5 ±2.71 mv and 81.9 ± 2.43 %, respectively. In vivo, liposomalencapsulation allowed a 3.34-fold increase in relativebioavailability compared to free capsaicin. The gastricmucosa irritation studies indicated that the liposomal systemwas a safe carrier for oral administration. These resultssupport the fact that capsaicin, an effective drug for thetreatment of neuropathic pain, could be encapsulated inliposome for improved oral bioavailability. The excellentIVIVC of capsaicin-loaded liposome could also be a promisingtool in liposomal formulation development with anadded advantage of reduced animal testing.

Robust Consensus for Networked Mechanical Systems with Coupling Time Delay

Haibo Min,Shicheng Wang,Fuchun Sun,Jinsheng Zhang 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.2

This paper studies the state consensus for a class of networked nonlinear mechanical systems with coupling time delay. In particular, robust consensus protocols for both deterministic and uncertain systems with time delay are investigated. For deterministic systems, we develop a P-like protocol which allows for variable coupling time delay. We show that it is sufficient to have only the relative position information together with a damping control term, whereas the relative velocity information is not needed for state consensus. Then, an adaptive robust control protocol is proposed for uncertain sys-tems with unknown parameters in the system dynamics and arbitrary constant coupling time delays. By introducing the passivity-based framework, we demonstrate that state consensus is still reachable in this case. Finally, a numerical example is included to illustrate the obtained results.

Research of Optimal Investment Size for Distribution Network Based on Improved Sequential Quadratic Programming Method

Zeng Ming,Wang Shicheng 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.2

Installing distributed generators can effectively reduce network power consumption and improve power quality in the distribution network, but it will also bring some technical problems. Therefore, we need to study how to efficiently and quickly determine the optimal investment capacity of distributed generators in the distribution network. In this paper, we set the minimization of the power loss as the objective and establish the most investment scale decision-making model of distributed generation access to power distribution system. In terms of optimization algorithm, optimization time of traditional sequential quadratic programming will dramatically increase with the increasing number of variables and restraints. In order to pursue higher efficiency optimization, we apply the improved sequential quadratic programming that is fast sequential quadratic programming method for solving nonlinear problems of distributed generators optimal investment size. We apply the constructed model to systems with different nodes, and the results show that the proposed new optimization method is not only scientific and effective, and can significantly improve decision-making efficiency.

Distributed Finite-time Regulation of a Class of Networked Heterogeneous Multi-agent Systems

Yuan Liu,Shicheng Wang,Haibo Min,Long Ma,Dacheng Luo 제어·로봇·시스템학회 2015 International Journal of Control, Automation, and Vol.13 No.1

In this paper, we investigate the finite-time regulation problem for heterogeneous multiagent system composed of linear first-order, second-order integrator agents and nonlinear Euler- Lagrange (EL) dynamical agents. Based on homogeneity approach, a continuous finite-time controller is designed. A distinctive feature of this work is to address the finite-time consensus problem of firstorder, second-order integrator agents and nonlinear EL agents in a unified theoretical framework. Simulation results are also provided to illustrate the effectiveness of the controller.

Valorization of lignocellulosic fibres of paper waste into levulinic acid using solid and aqueous Brønsted acid

Chen, Season S.,Wang, Lei,Yu, Iris K.M.,Tsang, Daniel C.W.,Hunt, Andrew J.,Jé,rô,me, Franç,ois,Zhang, Shicheng,Ok, Yong Sik,Poon, Chi Sun Elsevier 2018 Bioresource technology Vol.247 No.-

<P><B>Abstract</B></P> <P>This study aims to produce levulinic acid (LA) from paper towel waste in environment-friendly and economically feasible conditions, and evaluate the difference using solid and aqueous Brønsted acids. Direct dehydration of glucose to LA required sufficiently strong Brønsted acidity, where Amberlyst 36 demonstrated rapid production of approximately 30Cmol% of LA in 20min. However, the maximum yield of LA was limited by mass transfer. In contrast, the yield of LA gradually increased to over 40Cmol% in 1M H<SUB>2</SUB>SO<SUB>4</SUB> at 150°C in 60min. The SEM images revealed the conversion in dilute acids under microwave at 150°C resulting in swelling structures of cellulose, which were similar to the pre-treatment process with concentrated acids. Further increase in reaction temperature to 200°C significantly shortened the reaction time from 60 to 2.5min, which saved the energy cost as revealed in preliminary cost analysis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> 30% of levulinic acid (LA) yielded from paper towel over Amberlyst 36 in 20min. </LI> <LI> Maximum yield of LA was comparable using dilute sulphuric acid at 150 and 200°C. </LI> <LI> Cellulose underwent swelling in dilute acid with microwave heating at 150°C. </LI> <LI> Conversion at 200°C shortened reaction time and reduced total energy consumption. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Porphyra Species: A Mini-Review of Its Pharmacological and Nutritional Properties

Jin Cao,Jianping Wang,Shicheng Wang,Ximing Xu 한국식품영양과학회 2016 Journal of medicinal food Vol.19 No.2

Porphyra sensu lato belongs to Bangiales, the most genetically diverse order of red algae. Porphyra or Pyropia is widely cultivated in East Asian countries, such as China, Japan, and Korea. Dried Porphyra contains numerous nutritional and biofunctional compounds, including proteins, minerals, dietary fiber, polyunsaturated fatty acids, carotenoids, saccharides, and mycosporine-like amino acids. In addition, the compound is most abundant in Porphyra, such as polysaccharides and phycobiliproteins, and demonstrates various immunomodulating, anticancer, antihyperlipidemic, and antioxidative activities. This review summarizes our current knowledge concerning the pharmacologically active substances found in Porphyra species. The biological activities and potential applications of certain carbohydrates, proteins, peptides, and other small molecules purified from Porphyra are also described, and possible areas for future studies are discussed.

Role of silibinin in the management of diabetes mellitus and its complications

Chun Chu,Da-Hong Li,Shicheng Zhang,Takashi Ikejima,Ying Jia,Dongkai Wang,Fanxing Xu 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.8

Diabetes mellitus is globally approaching epidemicproportions and acts as a major cause of a number ofserious health problems diagnosed as diabetic complications. The current oral drugs in the treatment of diabetesand its complications could meet some but not all of thepatients’ needs, and the development of novel drugs with ahypoglycemic effect is urgently required. Silibinin, aflavonolignan traditionally used for the treatment of gallbladderand hepatic diseases, was reported to improveglycemic homeostasis by improving the activity of pancreaticb-cells, increasing insulin sensitivity of liver andmuscle cells, and decreasing lipid deposition in adipocytes. Researches also indicated the effectiveness of silibinin incontrolling several diabetic complications including neuropathy,retinopathy, impaired healing, hepatopathy, cardiomyopathy,nephropathy, and osteoporosis. In thisreview, we summarize the recent anti-diabetes findings ofsilibinin and clarify the underlying pharmacologicalmechanisms, and update the knowledge in understandingthe role of silibinin in control of diabetic complications.

Microwave-assisted low-temperature hydrothermal treatment of red seaweed (<i>Gracilaria lemaneiformis</i>) for production of levulinic acid and algae hydrochar

Cao, Leichang,Yu, Iris K.M.,Cho, Dong-Wan,Wang, Di,Tsang, Daniel C.W.,Zhang, Shicheng,Ding, Shiming,Wang, Linling,Ok, Yong Sik Elsevier 2019 Bioresource technology Vol.273 No.-

<P><B>Abstract</B></P> <P>In this study, red seaweed (<I>Gracilaria lemaneiformis</I>) food waste with high carbohydrate content was valorized into levulinic acid (LA) and algae hydrochar through microwave-assisted low-temperature hydrothermal treatment in dilute acid solution. Various parameters including treatment temperature (160–200 °C), reaction time (1–40 min), acid concentration (0–0.6 M), and biomass-to-liquid ratio (1%–10%, w/v) were examined. The energy efficiency and carbon recovery of the proposed process were investigated. Under the experimental conditions of 5% (w/v) biomass loading, 0.2 M H<SUB>2</SUB>SO<SUB>4,</SUB> 180 °C, and 20 min, the highest levulinic acid yield of 16.3 wt% was produced. The resulting hydrochar showed approximately 45–55% energy yield and higher heating values of 19–25 MJ kg<SUP>−1</SUP>. The energy efficiency of the present study (1.31 × 10<SUP>−6</SUP> g LA/J) was comparable to those of the conventional hydrothermal treatment of lignocellulosic biomass, while the reaction time (20 min) was much shorter with a high carbon recovery (73.3%).</P> <P><B>Highlights</B></P> <P> <UL> <LI> Red seaweed food waste was used as a sustainable feedstock for LA production. </LI> <LI> Microwave-assisted hydrothermal treatment facilitated fast red seaweed conversion. </LI> <LI> High LA yield of 16.3 wt% was obtained from <I>Gracilaria lemaneiformis</I>. </LI> <LI> Algae hydrochar recovered can serve as a potential solid fuel. </LI> <LI> Energy efficiency of 1.31 × 10<SUP>−6</SUP> g LA/J and high carbon recovery of 73.3% were achieved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>