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mathematical Modeling of Cell Polarity Establishment of Budding Yeast

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Communications on Applied Mathematics and Computation 2024年第1期6卷 218-235页

作者： Yue Liu Jun Xie Hay-Oak Park Wing-Cheong Lo Department of Mathematics City University of Hong KongTat Chee AvenueKowloonHong KongChina Department of Molecular Genetics The Ohio State UniversityColumbusOHUSA

The budding yeast Saccharomyces cerevisiae is a powerful model system for studying the cell polarity *** cell polarization process is regulated by signaling molecules,which are initially distributed in the cytoplasm and then recruited to a proper location on the cell membrane in response to spatial cues or *** of these signaling molecules involves complex regulation,so the mathematical models become a useful tool to investigate the mechanism behind the *** this review,we discuss how mathematical modeling has shed light on different regulations in the cell *** also propose future applications for the mathematical modeling of cell polarization and morphogenesis.

关键词： Budding yeast Cdc42 Morphogenesis Septin mathematical models

Review of wax sedimentations prediction models for crude-oil transportation pipelines

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Petroleum Research 2022年第2期7卷 220-235页

作者： Ballo Mwendapole Lonje Gang Liu College of Pipelines and Civil Engineering China University of Petroleum East ChinaQingdao266580China

Wax sedimentation in pipelines is a severe crude oil production and transportation *** surface roughness is experienced at the early stages of the problem;with time,the effective pipe cross-sectional area is reduced due to pipeline wax plugging,causing pumping pressure increase,equipment failures,and blockages,resulting in unnecessary downtime costs and pipeline abandonments in the worst *** paper reviews mathematical and experimental loops models used for pipeline solid wax predictions and calculations as functions of pressure,temperature,and fluid composition;by assessing model's Assumptions,strengths and *** is found that most mathematical models applied molecular-diffusion mechanisms in modeling and neglected shear effects;which resulted in wax *** loop was time-consuming due to mounting and dismounting of test section during wax deposition measurements;our modification has included sensor-integration to detect,measure,and analyze wax deposition;Reliable wax predictions models are essential to properly design pipelines and adopt cost-effective strategies for wax deposition prevention,control,and removal.

关键词： Prediction models Experimental loops mathematical models Wax sedimentation Wax appearance temperature

Evaluations of COVID-19 epidemic models with multiple susceptible compartments using exponential and non-exponential distribution for disease stages

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Infectious Disease Modelling 2022年第4期7卷 795-810页

作者： Yan Chen Haitao Song Shengqiang Liu School of mathematical Sciences Tiangong UniversityTianjin300387China Complex Systems Research Center Shanxi UniversityTaiyuan030006China

mathematical models have wide applications in studying COVID-19 epidemic transmission dynamics,however,most mathematical models do not take into account the heterogeneity of susceptible populations and the non-exponential distribution infectious *** paper attempts to investigate whether non-exponentially distributed infectious period can better characterize the transmission process in heterogeneous susceptible populations and how it impacts the control *** this purpose,we establish two COVID-19 epidemic models with heterogeneous susceptible populations based on different assumptions for infectious period:the first one is an exponential distribution model(EDM),and the other one is a gamma distribution model(GDM);explicit formula of peak time of the EDM is presented via our analytical *** data fitting with the COVID-19(Omicron)epidemic in Spain and Norway,it seems that Spain is more suitable for EDM while Norway is more suitable for ***,we use EDM and GDM to evaluate the impaction of control strategies such as reduction of transmission rates,and increase of primary course rate(PCR)and booster dose rate(BDR).

关键词： mathematical models COVID-19 Exponential distribution Gamma distribution Peak time

Tumor Classification of Gene Expression Data by Fuzzy Hybrid Twin SVM

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Chinese Journal of Electronics 2022年第1期31卷 99-106页

作者： DUAN Hua FENG Tong LIU Songning ZHANG Yulin SU Jionglong College of Mathematics and Systems Science Shandong University of Science and Technology School of AI and Advanced Computing XJTLU Entrepreneur College (Taicang) Xi'an Jiaotong-Liverpool University

A new classification model, the fuzzy hybrid twin support vector machine(TWSVM), namely FHTWSVM, is proposed by combining the fuzzy TWSVM and the hypersphere support vector machine(SVM).The hypersphere SVM is utilized for generating the hyperspheres for the positive and negative class with the smallest possible radius, so that the hyperspheres can contain as many samples as possible. The samples which the hyperspheres cover form a new sample set. Furthermore a distance-based fuzzy function is utilized to calculate the fuzzy factors for the samples. Finally FHTWSVM is used to train all samples with the parameters optimized by grid search. This method can maximize intra-class clustering for noise removal and reduce the influence of *** demonstrate the superiority of the performance of FHTWSVM over other classifiers, e.g., KNN, RF,Bayesian, TWSVM, Ada Boost and XGBoost, a series of experiments is conducted using eight gene expression datasets. The evaluation results show that the proposed approach can improve the classification performance as well as reduce prediction errors for the datasets.

关键词： Support vector machines Training Gene expression Speech recognition mathematical models Tumors Task analysis

A Hypernetwork Based Model for Emergency Response System

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Chinese Journal of Electronics 2022年第1期31卷 129-136页

作者： WANG Wei LIU Shufen LI Bing College of Computer Science and Technology Jilin University

Current emergency response systems are facing several challenges, including complex emergency network structure definition and inefficient emergency scheduling. For these problems, the paper analyzes the characteristics of emergency networks, and abstracts them into multiple interconnected, interdependent and interactive networks according to the characteristics of hierarchy, attribute and function, and then proposes a hypernetwork based model and its constraint conditions. Furthermore, the paper proposes an emergency scheduling method. This method fully considers the psychological factors of people and the rescue cost factors in disasters in order to balance the interests among different levels of network during rescue. The experiment results show that the model and the method proposed in this paper can not only better reveal the composition and structure of emergency response system, but also effectively balance the cost and the satisfaction in rescue.

关键词： Emergency services Costs Organizations Complex networks Scheduling mathematical models Stochastic processes

MILP-Based Linear Attacks on Round-Reduced GIFT

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Chinese Journal of Electronics 2022年第1期31卷 89-98页

作者： CUI Yaxin XU Hong QI Wenfeng Information Engineering University

GIFT is a lightweight block cipher with an substitution-per mutation-net work（SP N） structure proposed in CHES *** has two different versions whose block sizes are 64 and 128 *** RSA 2019,Zhu et *** some differential characteristics of GIFT with mixed integer linear programming（MILP） method and presented corresponding differential *** this paper,we further find some linear characteristics with MILP *** GIFT-64,we find two 11-round linear characteristics with correlation 2;,and use one of them to present a 16-round linear attack on GIFT-64 by adding4 rounds before and one round after the linear *** GIFT-128,we find a 16-round linear characteristic with correlation 2;.As far as we know,it is the longest linear characteristic found for *** the 16-round linear characteristic,we present a 20-round linear attack on GIFT-128 by adding 2 rounds before and2 rounds after the linear characteristic.

关键词： Correlation Ciphers Sun Integrated circuits Ear Time complexity mathematical models

Maximum Correntropy High-Order Extended Kalman Filter

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Chinese Journal of Electronics 2022年第1期31卷 190-198页

作者： SUN Xiaohui WEN Chenglin WEN Tao School of Automation Hangzhou Dianzi University School of Automation Guangdong University of Petrochemical Technology School of Electronic and Information Engineering Beijing Jiaotong University

In this paper, a novel maximum correntropy high-order extended Kalman filter(H-MCEKF) is proposed for a class of nonlinear non-Gaussian systems presented by polynomial form. All high-order polynomial terms in the state model are defined as implicit variables and regarded as parameter variables; the original state model is equivalently formulated into a pseudo-linear form with original variables and parameter variables; the dynamic relationship between each implicit variable and all variables is modeled, then an augmented linear state model appears by combing with pseudo-linear state model; similarly, the nonlinear measurement model can be equivalently rewritten into linear form; once again, the statistical characteristics of non-Gaussian modeling error are described by mean value and variance based on their finite samples; combing original measurement model with predicted value regarded as added state measurement, a cost function to solve the state estimation based on maximum correntropy criterion(MCC) is constructed; on the basis of this cost function, the state estimation problem can be equivalently converted into a recursive solution problem in the form of Kalman filter, in which the filter gain matrix is solved by numerical iteration though its fixed-point equation; illustration examples are presented to demonstrate the effectiveness of the new algorithm.

关键词： Kalman filters Random variables Taylor series mathematical models State estimation Nonlinear filters Measurement uncertainty

A Fast Two-Tone Active Load-Pull Algorithm for Assessing the Non-linearity of RF Devices

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Chinese Journal of Electronics 2022年第1期31卷 25-32页

作者： SU Jiangtao CAI Jialing ZHENG Xing SUN Lingling Key Laboratory of RF Circuits and Systems Ministry of Education Key Laboratory of Large Scale Integrated Circuits Design Zhejiang Province

Radio frequency(RF) devices used in modern wireless systems must meet increasingly complicated spectral constraints while still operating with high power efficiency. A fast real-time two-tone active loadpull algorithm is proposed to assess the relationship between nonlinear performance with associated device load impedance variations. This algorithm employs real time measurement data to extract two-tone local nonlinear behaviour model, which is further used for the prediction of injected signal value in the active real-time loadpull system, therefore minimizing the number of iterations required for load emulation. The proposed method was validated on a real two-tone load-pull measurement bench using off-the-shelf instruments. The result shows that the measurement speed has been greatly increased without sacrifice of the impedance emulation *** intelligent two-tone load-pull algorithm is expected to be applied in the designing of modern communication system and radar transmitters, as well as the validation of the models of radio frequency transistors.

关键词： Load modeling Impedance Radio frequency mathematical models Signal processing algorithms Performance evaluation Harmonic analysis

Predictive models of Adjuvant Chemotherapy for Patients with Stage II Colorectal Cancer： A Retrospective Study

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Chinese Medical Journal 2017年第17期130卷 2069-2075页

作者： Bo Wei Xiao-Ming Zheng Pu-Run Lei Yong Huang Zong-Heng Zheng Tu-Feng Chen Jiang-Long Huang Jia-Feng Fang Cheng-Hua Liang Hong-Bo Wei Department of Gastrointestinal Surgery The Third Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510630 China

Background：It remains controversial whether patients with Stage II colorectal cancer would benefit from adjuvant chemotherapy after radical *** aim of this study was to establish two mathematical models to identify the suitable patients for adjuvant ***：The current study comprised of two *** the first step,353 patients with Stage Ⅱ colorectal cancer who underwent surgical procedures at the Third Affiliated Hospital of Sun Yat-sen University between June 2006 and December 2015 were entered and followed up for 6-120 *** clinical data were collected and enrolled into the *** established two mathematical models by univariate and multivariate Cox regression analysis to identify the target patients;in the second step,230 patients under the same standard between January 2012 and December 2016 were entered and followed up for 3-62 months to verify the two models＆#39; ***：In the first step,totally 340 surgical patients with Stage Ⅱ colorectal cancer were finally enrolled in this *** analysis showed that tumor differentiation （TD）（P 〈 0.001）,lymphovascular invasion （LVI）（P 〈 0.001）,uncertain or positive margins （UPM）（P 〈 0.001）,and fewer lymph nodes （LNs）（〈12） retrieved （P 〈 0.001） were correlated with the overall survival （OS） and disease free survival （DFS）.We obtained two models：（1） OS risk score =1.116 ＆#215; TD ＆#177; 2.202 ＆#215; LVI ＋ 3.676 ＆#215; UPM ＋ 1.438 ＆#215; LN-0.493;（2） DFS risk score =0.789 ＆#215; TD ＋ 2.074 ＆#215; LVI ＋ 3.183 ＆#215; UPM ＋ 1.329 ＆#215; *** to the models and cutoff points [（0.07,1.33） and （-0.04,1.30）,respectively],patients can be divided into three groups：low-risk,moderate-risk,and ***,the high-risk group patients could benefit from adjuvant *** the second step,totally 221 patients were finally used to verify the models＆#39; *** results proved that the models were accurate and feasible （P 〈 0.05）.Conclusions：A

关键词： Adjuvant Chemotherapy Risk Factors mathematical models Colorectal Cancer

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