Multi-stage Nonlinear Model Predictive Control with Online Scenario Update for Semi-batch Polymerization Processes

Jing-Gao Sun,Xian-Feng Chen,Guang-Hao Su,Meng Wang,Hong-Guang Pan 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.10

In this paper, the problem of multi-stage nonlinear model predictive control with scenario update is investigated for semi-batch polymerization processes. The objective is to propose novel online scenario update schemes such that the more reasonable scenario tree can be generated. Firstly, based on the Orthogonal Configuration of Finite Elements (OCFE) method of direct radau configuration, the dynamic optimization problems are converted to Nonlinear Programing (NLP) problems such that the speed and accuracy of real-time optimization problem solving are effectively improved. Then, the scenario deviation is calculated based on model prediction information of each scenario and process measurement information. After that, calculate the bayesian probability weight of corresponding scenario is obtained. The online scenario reduction scheme uses the weight information update scenarios gradually reduce the scope of scenario tree representation. The online scenario weight update scheme uses the weight information as the basis for weight assignment of each scenario in the optimization problem. They use different methods to make the scenario tree modeling approach the real realization of uncertainty, and reduce the conservativeness compared with the traditional MSNMPC fixed scenario tree method. Through multiple batches numerical simulations of a semi-batch polymerization process, the advantages and effectiveness of the two proposed schemes are verified.

A comparison of the fracture resistances of endodontically treated mandibular premolars restored with endocrowns and glass fiber postcore retained conventional crowns

Jing Guo,Zhiming Wang,Xuesheng Li,Chaoyang Sun,Erdong Gao,Hongbo Li 대한치과보철학회 2016 The Journal of Advanced Prosthodontics Vol.8 No.6

PURPOSE This in-vitro study aimed to evaluate the fracture resistances and failure modes of endodontically treated mandibular premolars restored with endocrowns and conventional post-core retained crowns. MATERIALS AND METHODS Thirty mandibular premolars were assigned into three groups (n=10): GI, intact teeth; GE, teeth with endocrowns; GC, teeth with conventional post-core supported crowns. Except for the teeth in group GI, all specimens were cut to 1.5 mm above the cementoenamel junction and endodontically treated. Both endocrowns and conventional crowns were fabricated from lithium-disilicate blocks using a CEREC 3D CAD/CAM unit. All specimens were subjected to thermocycling and then to 45° oblique compressive load until fracture occurred. The fracture resistance and failure mode of each specimen were recorded. Data were analyzed with one-way ANOVA and LSD Post Hoc Test (α=.05). RESULTS The fracture resistances of GE and GC were significantly lower than that of GI (P<.01), while no significant difference was found between GE and GC (P=.702). As of the failure mode, most of the specimens in GE and GC were unfavorable while a higher occurrence of favorable failure mode was presented in GI. CONCLUSION For the restoration of mandibular premolar, endocrown shows no advantage in fracture resistance when compared with the conventional method. Both of the two methods cannot rehabilitate endodontically treated teeth with the same fracture resistances that intact mandibular premolars have.

Effects of dynamic transmission errors and vibration stability in helical gears

Jing Wei,Pan Gao,Xinglong Hu,Wei Sun,Jing Zeng 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.6

Transmission error is an important reason for instability in helical gears. A six-degree-of-freedom dynamic model coupled flexional,torsional and axial motion of a helical gear transmission system, which includes time varying mesh stiffness, bearing supporting stiffness,mesh damping and backlash, is developed, after taking into account the dynamic characteristics and vibration responses of helical gear inthree dimensions. Influences of involute contact ratio, bearing supporting stiffness, mesh damping and backlash on the dynamic transmissionerrors and vibration stability of the helical gear system are investigated using numerical simulation technique. The effects on dynamictransmission errors and stabilities by contact ratio, supporting stiffness and mesh damping as well as gear backlash are analyzed. The intrinsic relationship between above parameters and dynamic transmission errors and stabilities for helical gear system are presented. The stable and unstable regions under different parameters are given. The results in this paper can be helpful to the dynamic and stabledesign of a helical gear transmission system.

Electromagnetic Field Exposure and Male Breast Cancer Risk: A Meta-analysis of 18 Studies

Sun, Jing-Wen,Li, Xiao-Rong,Gao, Hong-Yu,Yin, Jie-Yun,Qin, Qin,Nie, Shao-Fa,Wei, Sheng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Background: The possibility that electromagnetic fields (EMF) exposure may increase male breast cancer risk has been discussed for a long time. However, arguments have been presented that studies limited by poor quality could have led to statistically significant results by chance or bias. Moreover, data fo the last 10 years have not been systematically summarized. Methods and Results: To confirm any possible association, a meta-analysis was performed by a systematic search strategy. Totals of 7 case-control and 11 cohort studies was identified and pooled ORs with 95% CIs were used as the principal outcome measures. Data from these studies were extracted with a standard meta-analysis procedure and grouped in relation to study design, cut-off point, exposure assessment method, adjustment and exposure model. A statistical significant increased risk of male breast cancer with EMF exposure was defined (pooled ORs = 1.32, 95% CI = 1.14-1.52, P < 0.001), and subgroup analyses also showed similar results. Conclusions: This meta-analysis suggests that EMF exposure may be associated with the increase risk of male breast cancer despite the arguments raised.

A comparison of the fracture resistances of endodontically treated mandibular premolars restored with endocrowns and glass fiber post-core retained conventional crowns

Guo, Jing,Wang, Zhiming,Li, Xuesheng,Sun, Chaoyang,Gao, Erdong,Li, Hongbo The Korean Academy of Prosthodonitics 2016 The Journal of Advanced Prosthodontics Vol.8 No.6

PURPOSE. This in-vitro study aimed to evaluate the fracture resistances and failure modes of endodontically treated mandibular premolars restored with endocrowns and conventional post-core retained crowns. MATERIALS AND METHODS. Thirty mandibular premolars were assigned into three groups (n=10): GI, intact teeth; GE, teeth with endocrowns; GC, teeth with conventional post-core supported crowns. Except for the teeth in group GI, all specimens were cut to 1.5 mm above the cementoenamel junction and endodontically treated. Both endocrowns and conventional crowns were fabricated from lithium-disilicate blocks using a CEREC 3D CAD/CAM unit. All specimens were subjected to thermocycling and then to $45^{\circ}$ oblique compressive load until fracture occurred. The fracture resistance and failure mode of each specimen were recorded. Data were analyzed with one-way ANOVA and LSD Post Hoc Test (${\alpha}=.05$). RESULTS. The fracture resistances of GE and GC were significantly lower than that of GI (P<.01), while no significant difference was found between GE and GC (P=.702). As of the failure mode, most of the specimens in GE and GC were unfavorable while a higher occurrence of favorable failure mode was presented in GI. CONCLUSION. For the restoration of mandibular premolar, endocrown shows no advantage in fracture resistance when compared with the conventional method. Both of the two methods cannot rehabilitate endodontically treated teeth with the same fracture resistances that intact mandibular premolars have.

A New Fuzzy Key Generation Method Based on PHY-Layer Fingerprints in Mobile Cognitive Radio Networks

( Ning Gao ),( Xiaojun Jing ),( Songlin Sun ),( Junsheng Mu ),( Xiang Lu ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.7

Classical key generation is complicated to update and key distribution generally requires fixed infrastructures. In order to eliminate these restrictions researchers have focused much attention on physical-layer (PHY-layer) based key generation methods. In this paper, we present a PHY-layer fingerprints based fuzzy key generation scheme, which works to prevent primary user emulation (PUE) attacks and spectrum sensing data falsification (SSDF) attacks, with multi-node collaborative defense strategies. We also propose two algorithms, the EA algorithm and the TA algorithm, to defend against eavesdropping attacks and tampering attacks in mobile cognitive radio networks (CRNs). We give security analyses of these algorithms in both the spatial and temporal domains, and prove the upper bound of the entropy loss in theory. We present a simulation result based on a MIMO-OFDM communication system which shows that the channel response characteristics received by legitimates tend to be consistent and phase characteristics are much more robust for key generation in mobile CRNs. In addition, NIST statistical tests show that the generated key in our proposed approach is secure and reliable.

Functionalization of carbon naotubes for nanoparticle attachment

Lian Gao,Yangqiao Liu,Jing Sun,Yan Wang 한양대학교 세라믹연구소 2010 Journal of Ceramic Processing Research Vol.11 No.1

In this paper, multiwalled carbon nanotubes (MWNTs) have been functionalized by two methods, which are a concentrated acid treatment and a noncovalent treatment by a polyelectrolyte. The structure of the carbon nanotubes after treatment has been characterized by Raman measurements. Zeta potential analysis shows that the carbon nanotubes become obviously negatively charged after these two treatments. Inorganic nanoparticles, including NiFe2O4, CdS and SnO2 are homogeneously attached onto the functionalized MWCNTs using an in situ formation method utilizing the electrical attraction between the functionalized MWCNTs and the metal ions. The composites obtained have been characterized by transmission electron microscopy (TEM) and energy dispersive spectroscopic (EDS) analysis. These composites can be potentially useful for fabricating catalysts, photovoltaic cells, lightemitting diodes, etc..

Electrospun Porcine Acellular Dermal Matrix and Polycaprolactone Composite Nanofibrous Scaffolds for Accelerating Wound Healing

Xiaofei Gao,Guohua Jiang,Liming Ruan,Yanfang Sun,Khaydar E. Yunusov,Yanting Jing,Uladzislau E. Aharodnikau,Sergey O. Solomevich 한국섬유공학회 2023 Fibers and polymers Vol.24 No.2

Electrospun nanofibers represent a novel class of scaffold materials that show great potential in wound healing owing torelatively large surface area, better mimicry of native extracellular matrix, adjustable waterproofness and breathability, andprogrammable drug delivery process. In this work, electrospun polycaprolactone (PCL) and porcine acellular dermal matrix(PADM) composite nanofibrous membranes have been developed by electrospinning technology and inflated into threedimensional(3D) structural scaffold (PCL-PADM) by gas foaming method. The obtained PCL-PADM has higher thermalstability, hydrophilicity and better cell adhesion compared with PCL. In addition, ε-polylysine (ε-PL) is further attachedonto the surface of PADM/PCL to offer its good antibacterial properties. Moreover, the PADM/PCL fibrous scaffolds showexcellent cytocompatibility for promoting cell proliferation. In vivo models showed that the resultant PADM/PCL fibrousscaffolds exhibit an accelerating wound healing effect through promoting expression of vascular factor (CD31) and decreasingthe expression of tumor necrosis factor-α (TNF-α). These results indicate that the 3D fibrous scaffolds may be a potentialwound dressing for wound closure.

Canonical transient receptor potential channels and their modulators: biology, pharmacology and therapeutic potentials

Yuan-Yuan Gao,Wen Tian,Hui-Nan Zhang,Yang Sun,Jing-Ru Meng,Wei Cao,Xiao-Qiang Li 대한약학회 2021 Archives of Pharmacal Research Vol.44 No.4

Canonical transient receptor potential channels(TRPCs) are nonselective, high calcium permeability cationicchannels. The TRPCs family includes TRPC1, TRPC2,TRPC3, TRPC4, TRPC5, TRPC6, and TRPC7. These channelsare widely expressed in the cardiovascular and nervoussystems and exist in many other human tissues and celltypes, playing several crucial roles in the human physiologicaland pathological processes. Hence, the emergenceof TRPCs modulators can help investigate these channels’applications in health and disease. It is worth noting that theTRPCs subfamilies have structural and functional similarities,which presents a signifi cant diffi culty in screening anddiscovering of TRPCs modulators. In the past few years,only a limited number of selective modulators of TRPCswere detected; thus, additional research on more potent andmore selective TRPCs modulators is needed. The presentreview focuses on the striking desired therapeutic eff ectsof TRPCs modulators, which provides intel on the structuralmodifi cation of TRPCs modulators and further pharmacologicalresearch. Importantly, TRPCs modulators cansignifi cantly facilitate future studies of TRPCs and TRPCsrelated diseases.

Chronic ethanol feeding impairs AMPK and MEF2 expression and is associated with GLUT4 decrease in rat myocardium

LiYong Chen,Jing Zhou,JiaJun Zhao,FuRong Wang,XiangLan Sun,Ling Gao,YuLian Jiao,XiaoLei Hou,ChengYong Qin 생화학분자생물학회 2010 Experimental and molecular medicine Vol.42 No.3

Chronic and heavy alcohol consumption is one of the causes of heart diseases. However, the effects of ethanol on insulin sensitivity in myocardium has been unclear. To investigate the effects of ethanol on the expression of AMP-activated protein kinase (AMPK), myocyte enhancer factor 2 (MEF2) and glucose transporter 4 (GLUT4), all of which are involved in the regulation of insulin sensitivity, in the myocardium, we performed three parts of experiments in vivo and in vitro. I: Rats were injected with 5-amino-4-imidazolecarboxamide ribonucleotide (AICAR, 0.8 mg.kg-1) for 2 h. II:Rats received different dose (0.5, 2.5 or 5 g.kg-1.d-1) of ethanol for 22-week. III: Primary neonatal rat cardiomyocytes were isolated and treated with or without 100 mM ethanol or 1 mM AICAR for 4 h. The cardiac protein and mRNA expression of AMPKα subunits, MEF2and GLUT4 were observed by western-blotting and RT-PCR, respectively. Serum TNFα levels were assessed by ELISA. The results showed chronic ethanol exposure induced insulin resistance. Ethanol decreased the mRNA levels of AMPKα1 and α2, the protein levels of total- and phospho-AMPKα in cardiomyocytes. Similarly, ethanol showed inhibitory effects on both the mRNA and protein levels of MEF2A and 2D,and GLUT4 in a dose-response-like fashion. Correlation analysis implied an association between phospho-AMPKα and MEF2A or MEF2D, and between the levels of MEF2 protein and GLUT4 transcription. In addition,ethanol elevated serum TNFα level. Taken together,chronic ethanol exposure decreases the expression of AMPKα and MEF2, and is associated with GLUT4 decline in rat myocardium.