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Herbst双期拔牙矫治对颞下颌关节骨性结构影响的锥形束CT研究

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华西口腔医学杂志 2016年第5期34卷 498-501页

作者：陈维维桑婷黄臻伍军南昌市中西医结合医院口腔科南昌大学附属口腔医院正畸科南昌330006

目的应用锥形束CT(CBCT)研究Herbst双期拔牙矫治对颞下颌关节骨性结构的影响。方法选取15例以下颌后缩为主要临床表现的恒牙列早期安氏Ⅱ类错患者,采用Herbst双期拔牙矫治,在Herbst矫治器矫治前两周(T1期)、Herbst矫治器初戴入矫治时(T2...

目的应用锥形束CT(CBCT)研究Herbst双期拔牙矫治对颞下颌关节骨性结构的影响。方法选取15例以下颌后缩为主要临床表现的恒牙列早期安氏Ⅱ类错患者,采用Herbst双期拔牙矫治,在Herbst矫治器矫治前两周(T1期)、Herbst矫治器初戴入矫治时(T2.)、Herbst矫治器拆除时(T3期)及二期固定矫治器拆除时(T4期)时进行CBCT扫描,应用Invivo Dental软件对CBCT图像进行三维重建和相关测量。结果 1)14例患者(2.侧颞下颌关节)在T3期出现髁突后上区外侧边缘高密度、内部区域低密度类似"新月形"的增生影像。2.T3-T2.、T4-T1期,髁突前后径平均增加了0.62.0.66 mm(P<0.01);髁突头高度平均增加了0.54、0.53 mm(P<0.01)。结论 Herbst功能矫治器能促进髁突发生生长改建。

关键词：双期矫治 Herbst矫治器颞下颌关节锥形束CT

颧牙槽嵴微种植体植入与上颌窦底位置关系的解剖研究

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上海口腔医学 2017年第6期26卷 623-627页

作者：王鹏陈铮晰吴军陈振琦上海市浦东医院口腔科上海201200 上海交通大学医学院附属第九人民医院.口腔医学院口腔正畸科上海200011

目的 :通过对颧牙槽嵴区微种植体植入与上颌窦底位置关系进行研究,以期为临床上在颧牙槽嵴处安全植入种植钉提供参考。方法:对19例正畸患者的37个上颌第一恒磨牙根方的颧牙槽嵴进行锥形束CT(CBCT)测量和分析,依上颌窦底位置分为窦低组... 详细信息

目的 :通过对颧牙槽嵴区微种植体植入与上颌窦底位置关系进行研究,以期为临床上在颧牙槽嵴处安全植入种植钉提供参考。方法:对19例正畸患者的37个上颌第一恒磨牙根方的颧牙槽嵴进行锥形束CT(CBCT)测量和分析,依上颌窦底位置分为窦低组与窦高组,比较2.之间颧牙槽嵴宽度的差别。同时测量上颌第一恒磨牙的近远中颊根的根长,以确定上颌种植钉植入的部位。采用SPSS2..0软件包对数据进行统计学分析。结果:窦低组的颧牙槽嵴宽度显著小于窦高组的颧牙槽嵴宽度,窦低组2.例,窦高组13组。男性上颌第一恒磨牙的近远中颊根长度平均值为12.62.mm和12.30 mm,女性近远中颊根的长度平均值为11.53 mm和11.15 mm。结论:上颌窦底的位置决定了颧牙槽嵴的宽度,窦高组可以为种植体植入提供足够的骨质宽度支持。为确保牙根尖组织的安全,应在根尖上方1~2.mm以上植入。男性患者的植入部位约在釉-牙骨质界以上13.62.mm,女性约为12.53 mm。

关键词：颧牙槽嵴微种植体锥形束CT 上颌窦

Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble

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Nuclear Science and Techniques 2024年第3期35卷 216-227页

作者： Deng Liu Alam Noor A zhen-zhen Qin Yang Lei School of Mathematics and Physics Southwest University of Science and TechnologyMianyang 621010China School of Nuclear Science and Technology Southwest University of Science and TechnologyMianyang 621010China

The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output *** quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the ***,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists.

关键词： Neural network Two-body random ensemble Spin distribution of nuclear ground state

Number of Solitons Emerged in the Initial Profile of Shallow Water Using Convolutional Neural Networks

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Journal of Systems Science & Complexity 2024年第2期37卷 463-479页

作者： WANG zhen CUI Shikun School of Mathematical Sciences Dalian University of TechnologyDalian 116024China School of Mathematical Sciences Beihang UniversityBeijing 100191China

The soliton resolution conjecture proposes that the initial value problem can evolve into a dispersion part and a soliton ***,the problem of determining the number of solitons that form in a given initial profile remains unsolved,except for a few specific *** this paper,the authors use the deep learning method to predict the number of solitons in a given initial value of the Korteweg-de Vries(KdV)*** leveraging the analytical relationship between Asech^(2.(x)initial values and the number of solitons,the authors train a Convolutional Neural Network(CNN)that can accurately identify the soliton count from spatio-temporal *** trained neural network is capable of predicting the number of solitons with other given initial values without any additional *** extensive calculations,the authors demonstrate the effectiveness and high performance of the proposed method.

关键词： Convolutional neural network deep learning method KdV equation soliton

Design Research of a Novel Aftercool-Humidifier Concept for Humid Air Turbine Cycle

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Journal of Thermal Science 2024年第3期33卷 951-969页

作者： ZHANG Junzheng XU zhen School of Energy and Power Engineering Shandong UniversityJi’nan250061China Shandong Engineering Laboratory for High-efficiency Energy Conservation and Energy Storage Technology&Equipment Shandong UniversityJi’nan250061China

Humid air turbine cycle(HAT)has potential of electrical efficiencies comparable to combined cycle,with lower investment cost and NO_(x) *** typical heat exchanger network of HAT consists of intercooler(if there is),aftercooler,recuperator,economizer and humidifier,which brings higher efficiency but makes the system more *** simplify HAT layout,a novel humidifier concept is proposed by integrating the aftercooler into traditional counter-current *** on this concept,a one-dimensional model including pressure drop and exergy calculation is established to distinguish the thermodynamic and hydrodynamic characteristics,and then the structural parameters,such as the number of rows and columns,tube diameter,pitch and type for a micro HAT are *** results show that the aftercool-humidifier plays the same role as original aftercooler and humidifier,and can match the in-tube air,out-tube air and water stream well with lower *** the case of micro HAT cycle,the volume of heat and mass transfer area can be reduced by 47%compared with traditional *** major thermal resistance occurred in the convection heat transfer process inside the tube;however,using enhanced tube cannot effectively improve the compactness of device.

关键词： humid air turbine cycle humidifier thermodynamic analysis one-dimensional model

Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： Lu Tang zhen-Hua Zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB2.,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB2.**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB2. models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHB model,with a root-mean-square deviation of 0.0092.*** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=12. and 82.shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： zhen-yu Ouyang Jian-zhong Lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a *** in the past 2. years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid *** paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle *** this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be ***,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction

Design Optimization and Operating Performance of S-CO_(2. Brayton Cycle under Fluctuating Ambient Temperature and Diverse Power Demand Scenarios

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Journal of Thermal Science 2024年第1期33卷 190-206页

作者： YANG Jingze YANG zhen DUAN Yuanyuan Key Laboratory for Thermal Science and Power Engineering of MOE Beijing Key Laboratory for CO_(2) Utilization and Reduction TechnologyTsinghua UniversityBeijing 100084China

The supercritical CO_(2.(S-CO_(2.) Brayton cycle is expected to replace steam cycle in the application of solar power tower system due to the attractive potential to improve efficiency and reduce *** the concentrated solar power plant with thermal energy storage is usually located in drought area and used to provide a dispatchable power output,the S-CO_(2. Brayton cycle has to operate under fluctuating ambient temperature and diverse power demand *** addition,the cycle design condition will directly affect the off-design *** this work,the combined effects of design condition,and distributions of ambient temperature and power demand on the cycle operating performance are analyzed,and the off-design performance maps are proposed for the first time.A cycle design method with feedback mechanism of operating performance under varied ambient temperature and power demand is introduced *** show that the low design value of compressor inlet temperature is not conductive to efficient operation under low loads and sufficient output under high ambient *** average yearly efficiency is most affected by the average power demand,while the load cover factor is significantly influenced by the average ambient *** multi-objective optimization,the optimal solution of designed compressor inlet temperature is close to the minimum value of35℃ in Delingha with low ambient temperature,while reaches 44.15℃ in Daggett under the scenario of high ambient temperature,low average power demand,long duration and large value of peak load during the peak temperature *** the cycle designed with compressor inlet temperature of 35℃ instead of 44.15℃ in Daggett under light industry power demand,the reduction of load cover factor will reach 0.02.,but the average yearly efficiency can barely be improved.

关键词： supercritical CO_(2.Brayton cycle ambient temperature fluctuating power demand scenarios design optimization off-design performance

Polynomial-Time Key-Recovery Attacks Against NTRURe Encrypt from ASIACCS'15

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Journal of Systems Science & Complexity 2024年第3期37卷 1308-1325页

作者： LIU zhen PAN Yanbin zhenG Jinwei School of Cyber Science and Technology Hubei Key Laboratory of Applied MathematicsHubei UniversityWuhan 430062China Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

In ASIACCS 2.15, Nu nez, et al. proposed a proxy re-encryption scheme, named NTRURe Encrypt, based on NTRU, which allows a proxy to translate ciphertext under the delegator’s public key into a re-encrypted ciphertext that can be decrypted correctly by delegatee’s private key. Because of the potential resistance to quantum algorithm, high efficiency and various applications in real life,NTRURe Encrypt has drawn lots of attention and its security has been widely discussed and *** PQCrypto2.19, Liu, et al. proposed two key recovery attacks against it. However, their first attack heavily relies on a weaken decryption oracle, and the second attack needs to collect about 2.0ciphertexts from the same message by theoretical analysis, which makes both of the attacks unrealistic. In this paper, inspired by the broadcast attack against NTRU, the authors find out that for NTRURe Encrypt the delegator and the delegatee can efficiently recover each other’s private key in polynomial time without any unrealistic assumptions. In addition, the authors also show how to fix NTRURe Encrypt to resist the proposed attacks. As a by-product, the authors also show how to commit broadcast attacks against NTRU 2.01 with even dg, which was thought infeasible before.

关键词： Broadcast attack key recovery NTRU NTRUReEncrypt