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大学生智能手机成瘾的潜在类别及其特征

中华行为医学与脑科学杂志 2024年第8期33卷 742-748页

作者：张磊李雪常扩张辉首都医科大学医学人文学院北京100069 南开大学社会学院社会心理学系天津市介入脑机与智能康复重点实验室天津300350

目的探索大学生智能手机成瘾的潜在类别及其在心理和手机使用行为中的特征。方法2023年7月,选用自编基本信息调查问卷、病人健康问卷抑郁量表(patient health questionnaire,PHQ-9)、UCLA孤独感量表简版(short-form of UCLA loneliness ... 详细信息

目的探索大学生智能手机成瘾的潜在类别及其在心理和手机使用行为中的特征。方法2023年7月,选用自编基本信息调查问卷、病人健康问卷抑郁量表(patient health questionnaire,PHQ-9)、UCLA孤独感量表简版(short-form of UCLA loneliness scale,ULS-8)、交往焦虑量表(interaction anxiousness scale,IAS)、错失焦虑量表(fear of missing out scale,FOMOs)、反刍思维量表(ruminative responses scale,RRS)、简版无聊倾向量表(short form version of boredom proneness scale,BPS-SF)、青少年气质量表中的意志控制分问卷、智能手机依赖量表简版(short version of smartphone addiction scale,SAS-SV)对北京市206名大学生进行横断面调查。采集手机使用时间和频率数据。运用SPSS 25.0进行统计描述和组间比较,使用Python 3.8软件K-means算法进行聚类分析,通过随机森林算法评估不同类别影响因素的重要性。结果(1)手机成瘾[41.00(31.00,47.00)分]与抑郁[6.00(2.00,12.00)分]、孤独感[15.00(11.00,20.00)分]、社交焦虑[46.00(32.75,54.00)分]、错失焦虑[21.00(16.00,28.00)分]、反刍思维[26.00(22.00,29.00)分]、无聊倾向[41.50(32.00,49.25)分]、平均每日手机使用时间[(513.30±213.29)min]、平均每次手机使用时间[6.60(3.68,14.09)min]呈正相关(r=0.163~0.626,均P<0.05),与意志控制[49.00(44.00,59.00)分]呈负相关(r=-0.613,P<0.01)。(2)聚类分析结果显示,大学生智能手机成瘾存在3种潜在类别:非成瘾组(32.04%,66/206)、无聊型手机成瘾组(26.70%,55/206)、多风险型手机成瘾组(41.26%,85/206)。(3)不同潜在类别在抑郁、孤独感、社交焦虑、反刍思维、无聊倾向、意志控制、手机成瘾上的得分均差异有统计学意义(H=138.805,127.342,112.149,88.069,72.146,100.206,115.159,114.926;均P<0.001),在平均每日手机使用时间和次数、平均每次手机使用时间上均差异有统计学意义(F/H=7.548,9.332,16.086;均P<0.01)。(4)随机森林算法分析结果显示,非成瘾组特征重要性前3位依次为:意志控制、社交焦虑、错失焦虑,特征重要性分别为0.33、0.23、0.15;无聊型手机成瘾组特征重要性前3位依次为:无聊倾向、错失焦虑、孤独感,特征重要性分别为0.35、0.20、0.15;多风险型手机成瘾组特征重要性前3位依次为:错失焦虑、反刍思维、无聊倾向,特征重要性分别为0.29、0.19、0.17。结论大学生智能手机成瘾存在3种潜在类别,各类别在不同心理因素和手机使用行为上差异显著,未来可根据不同大学生群体特点采取针对性心理干预措施。

关键词：大学生手机成瘾聚类分析潜在类别人-情感-认知-执行交互模型

ON ACTION-MINIMIZING SOLUTIONS OF THE TWO-CENTER PROBLEM

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Acta Mathematica Scientia 2022年第6期42卷 2450-2458页

作者： kuo-chang CHEN Department of Mathematics National Tsing Hua UniversityHsinchuTaiwanChina

The two-center problem,also known as Euler's three-body problem,is a classic example of integrable *** its periodic solutions,planetary type solutions are periodic solutions which enclose both *** by advances on n-body and n-center problems via variational techniques developed during the past two decades,a recent paper(***.2022)shows the minimizing property of planetary type solutions for any given masses of centers at fixed positions,as long as the period is above a mass-dependent threshold *** this paper,we provide further discussions regarding this minimizing *** particular,we improve the above-mentioned mass-dependent threshold value by refining estimates for action values.

关键词： two-center problem n-body problem variational method collision singularity

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吴茱萸次碱的结构修饰研究进展

中国新药杂志 2024年第2期33卷 138-145页

作者：宋继庭魏洪卓赵长阔王先恒遵义医科大学基础药理教育部重点实验室暨特色民族药教育部国际合作联合实验室遵义563000 遵义医科大学药学院遵义563000

吴茱萸次碱(rutaecarpine)是从传统中药吴茱萸中分离出来的一种喹唑啉类生物碱,具有广泛的生物学和药理学活性,吸引了大量学者和专业人员对其进行研究.迄今,对吴茱萸次碱的研究主要包括从新的天然来源中分离提取和开发新的全合成方法,... 详细信息

吴茱萸次碱(rutaecarpine)是从传统中药吴茱萸中分离出来的一种喹唑啉类生物碱,具有广泛的生物学和药理学活性,吸引了大量学者和专业人员对其进行研究.迄今,对吴茱萸次碱的研究主要包括从新的天然来源中分离提取和开发新的全合成方法,发现新的生物活性、代谢、毒理学性质、结构修饰与活性的关系、含量测定分析方法的建立等.随着研究的不断深入,发现吴茱萸次碱的溶解性很低,这影响了其吸收效率,其高细胞毒性也阻碍了其作为药物的发展.于是,众多学者对吴茱萸次碱结构修饰和改造做了大量研究,发现了一些新的、更好的生物活性结构.本文综述了近年来吴茱萸次碱结构修饰方面的研究,以期为寻找具有开发前景的吴茱萸次碱衍生物提供依据.

关键词：吴茱萸次碱结构修饰生物活性类似物研究进展

A Three-Point Method for Separating Incident and Reflected Waves over A Sloping Bed

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China Ocean Engineering 2002年第4期17卷 499-511页

作者： chang Hsien-kuo Department of Civil Engineering National Chiao Tung UniversityHsinchu 300China

This study presents a three-point method for separating incident and reflected waves to explain normally incident waves' propagating over a sloping bed. linear wave shoaling is used to determine changes in wave amplitude and phase in response to variations of bathymetry. The wave reflection coefficient and incident amplitude are estimated from wave heights measured at three fixed wave gauges with unequal spacing. Sensitivity analysis demonstrates that the proposed method can predict the reflection and amplitude of waves over a sloping bed more accurately than the two-point method.

关键词： reflected wave wave shoaling sloping bed

Characteristics and prognosis of small bowel tumors:A retrospective study

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World Journal of Clinical Cases 2024年第34期12卷 6696-6704页

作者： Fang-Chen Liu Ching-Hsiang Wang Peng-Jen Chen Yu-Lueng Shih Hsuan-Hwai Lin Jung-Chun Lin Wei-kuo chang Tsai-Yuan Hsieh Gen-Min Lin Tien-Yu Huang Division of Gastroenterology Department of Internal MedicineTri-Service General HospitalNational Defense Medical CenterTaipei 11490Taiwan Department of Internal Medicine Taoyuan Armed Forces General HospitalTaoyuan 325208Taiwan Department of Medicine Tri-Service General Hospital and National Defense Medical CenterTaipei 114Taiwan Department of Medicine Hualien Armed Forces General HospitalHualien 970Taiwan Taiwan Association for the Study of Small Intestinal Diseases Taoyuan 33305Taiwan

BACKGROUND Small bowel tumors(SBTs)are a heterogeneous group of difficult-to-diagnose tumors that account for 2%-5%of all gastrointestinal ***-balloon enteroscopy greatly enhances the diagnosis and treatment of ***,few epidemiological studies have been conducted in Taiwan to determine the clinical profile of *** To investigate the clinical characteristics,managements and prognosis of SBTs in a medical center in *** The study enrolled 51 patients aged 58.9±8.8 years(range,22-93)diagnosed with SBTs from November 2009 to July *** retrospectively recorded clinical characteristics,indications,endoscopic findings,pathological results,management,and outcomes for further *** A male preponderance was observed(56.8%).The most common indications were suspected small intestinal tumors(52.9%)and obscure gastrointestinal bleeding(39.2%).The most common tumor location was the ileum(41.2%).The performance of imaging studies(P=0.004)and the types of findings(P=0.005)differed significantly between malignant and benign *** most frequent imaging finding was a small intestinal mass(43.1%).The top three malignant tumor types were gastrointestinal stromal tumors(GISTs),adenocarcinomas,and ***,the proportions of benign and malignant tumors were 27.5%and 72.5%,*** survival rates of patients with malignant tumors in the GIST and non-GIST groups differed significantly(P=0.015).Kaplan–Meier survival analysis showed a significant difference in survival between patients in the malignant and benign groups(P=0.04).All patients with lymphoma underwent chemotherapy(n=7/8,87.5%),whereas most patients with GISTs underwent surgery(n=13/14,92.8%).CONCLUSION Patients with GISTs have a significantly higher survival rate than those with other malignant ***,a large-scale nationwide study is warranted to evaluate the population-based epidemiology of SBTs.

关键词： Gastrointestinal bleeding Intestinal neoplasms Single-balloon enteroscopy,survival rate

Distance Estimates for Simple Choreographic Solutions of the Three-body Problem

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Acta Mathematica Sinica,English Series 2022年第10期38卷 1823-1830页

作者： kuo chang CHEN Bo Yu PAN Department of Mathematics “National Tsing Hua University”HsinchuTaiwanChina Department of Applied Mathematics “National Chung Hsing University”TaichungTaiwanChina

In this article we estimate mutual distances of simple choreographic solutions for the Newtonian three-body *** formulas will be proved and our applications include the famous figure-8 orbit.

关键词： n-body problem variational method mutual distance

Electrical performance and reliability analysis of vertical gallium nitride Schottky barrier diodes with dual-ion implanted edge termination

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Chip 2024年第3期3卷 36-42页

作者： Bo Li Jinpei Lin Linfei Gao Zhengweng Ma Huakai Yang Zhihao Wu Hsien-Chin Chiu Hao-Chung kuo Chunfu Zhang Zhihong Liu Shuangwu Huang Wei He Xinke Liu College of Materials Science and Engineering College of Electronics and Information EngineeringInstitute of Microelectronics(IME)Guangdong Research Center for Interfacial Engineering of Functional MaterialsState Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Department of Electronic Engineering Chang Gung UniversityTaoyuan 333TaiwanChina Department of Photonics and the Institute of Electro-Optical Engineering and with Foxconn Semiconductor Research InstituteNational Chiao Tung UniversityHsinchu 300TaiwanChina Xidian University School of MicroelectronicsXi’an710071China

In this study,a galliumnitride(GaN)substrate and its 15μmepitaxial layer were entirely grown by adopting the hydride vapor phase epitaxy(HVPE)*** enhance the breakdown voltage(VBR)of vertical GaN-on-GaN Schottky barrier diodes(SBDs),a dual ion coimplantation of carbon and heliumwas employed to create the edge *** resulting devices exhibited a low turn-on voltage of 0.55 V,a high Ion/Ioff ratio of approximately 109,and a lowspecific onresistance of 1.93 mU cm^(2).When the ion implantation edge was terminated,the maximumVBR of the devices reached 1575 V,with an average improvement of 126%.These devices demonstrated a high figure of merit(FOM)of 1.28 GW cm^(-2) and showed excellent reliability during pulse stress testing.

关键词： Vertical GaN SBD HVPE Dual ion co-implantation Leakage mechanism Device reliability

Solving the Optimal Control Problems of Nonlinear Duffing Oscillators By Using an Iterative Shape Functions Method

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 33-48页

作者： Cheinshan Liu Chunglun kuo Jiangren chang Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung20224TaiwanChina Center of Excellence for the Oceans Taiwan Ocean UniversityKeelung20224TaiwanChina Department of Systems Engineering and Naval Architecture Taiwan Ocean UniversityKeelung20224TaiwanChina

In the optimal control problem of nonlinear dynamical system,the Hamiltonian formulation is useful and powerful to solve an optimal control ***,the resulting Euler-Lagrange equations are not easy to solve,when the performance index is complicated,because one may encounter a two-point boundary value problem of nonlinear differential algebraic *** be a numerical method,it is hard to exactly preserve all the specified conditions,which might deteriorate the accuracy of numerical *** this in mind,we develop a novel algorithm to find the solution of the optimal control problem of nonlinear Duffing oscillator,which can exactly satisfy all the required conditions for the minimality of the performance index.A new idea of shape functions method(SFM)is introduced,from which we can transform the optimal control problems to the initial value problems for the new variables,whose initial values are given arbitrarily,and meanwhile the terminal values are determined *** examples confirm the high-performance of the iterative algorithms based on the SFM,which are convergence fast,and also provide very accurate *** new algorithm is robust,even large noise is imposed on the input data.

关键词： Nonlinear Duffing oscillator optimal control problem Hamiltonian formulation shape functions method iterative algorithm

Long Wave Reflection and Transmission over A Sloping Step

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海洋工程：英文版 2004年第3期18卷 371-380页

作者： Hsien-kuo chang Jin-Cheng LIOU Department of Civil Engineering National Chiao Tung University 1001 Ta Hsuech Road Hsinchu 300 ChinaDepartment of Civil Engineering National Chiao Tung University 1001 Ta Hsuech Road Hsinchu 300 China

This investigation examines long wave reflection and transmission induced by a sloping step. Bellman and Kalaba's (1959) invariant imbedding is introduced to find wave reflection. An alternative method matching both the surface elevation and its surface slope of each region at the junction is applied to the determination of wave reflection and transmission. The proposed methods are compared with the accurate numerical results of Porter and Porter (2000) and those of Mei (1983) for a vertical step. The wave reflection obtained for a mildly sloping step differs significantly from the result of Mei. The wave reflection is found to fluctuate owing to wave trapping for the mild sloping step. The height and the face slope of the step are important for determining wave reflection and transmission coefficients.

关键词： long wave reflection coefficient wave transmission wave trapping