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State-to-state Photoionization Dynamics of Vanadium Nitride by Two-color Laser Photoionization and Photoelectron Methods

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Chinese Journal of Chemical Physics 2013年第6期26卷 669-678,I0003页

作者： Huang Huang Zhi-hong Luo yih chung chang Kai-chung Lau C. Y. Ng Department of Chemistry University of California Davis CA 95616 USA Department of Biology and Chemistry Oty University of Hone Kong Kowloon Hone Kong China

We have conducted a two-color visible-ultraviolet （VIS-UV） resonance-enhanced laser pho- toionization and pulsed field ionization-photoelectron （PFI-PE） study of gaseous vana- dium mononitride （VN） in the total energy range of 56900-59020 cm-1. The VN molecules were selectively excited to single rotational levels of the intermediate VN（D3H0, v＇=0） state by using a VIS dye laser prior to photoionization by employing a UV laser. This two-color scheme allows the measurements of rovibronically selected and re- solved PFI-PE spectra for the VN＋（X2A; v＋=0, 1, and 2） ion vibrational bands. By simulating the rotationally resolved PFI-PE spectra, J＋=3/2 is determined to be the lowest rotational level of the ground electronic state, indicating that the symmetry of the ground VN＋ electronic state is 2A3/2. The analysis of the PFI-PE spectra for VN＋ also yields accurate values for the adiabatic ionization energy for the formation of VN＋（X2A3/2）, IE（VN）=56909.5＋0.8 cm-1 （7.05588±0.00010 eV）, the vibrational fre- quency wc＋=1068.0±0.8 cm-1, the anharmonicity constant wc＋Xe＋=5.8±0.8 cm-1, the rotational constants Be＋=0.6563±0.0005 cm-1 and ae＋=0.0069±0.0004 cm-1, and the equi-librium bond length, re＋=1.529A, for VN＋（X2A3/2）; along with the rotational constants Bc＋=0.6578i0.0028 cm-1 and a＋=0.0085±0.0028 cm-1, and the equilibrium bond length re＋=1.527A for VN＋（X2As/2）, and the spin-orbit coupling constant A=153.3±0.8 cm-1 for VN＋（X2/k5/2,3/2）. The highly precise energetic and spectroscopic data obtained in the present study are valuable for benchmarking the predictions based on state-of-the-art ab initio quantum calculations.

关键词： Vanadium nitride Vanadium nitride cation Photoionization dynamics Two- color photoionization Pulsed field ionization-photoelectron Ionization energy Bond disso- ciation energy

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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3189-3208页

作者： Chein-Shan Liu chung-Lun Kuo Chih-Wen chang Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina Department of Mechanical Engineering National United UniversityMiaoli36063TaiwanChina

To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit *** can quickly determine the optimal values of the parameters within a preferred rage using the golden section search *** novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical ***,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being *** optimal MQ-RBF is extremely *** further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11).

关键词： Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method

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O(3P0,1,2,1D2) yield ratio measurement in VUV photodissociation of O2

O(3P0,1,2,1D2) yield ratio measurement in VUV photodissociat...

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第十五届全国化学动力学会议

作者：刘凯 yih chung chang Konstantinos S.Kalogerakis Tom G.Slanger Bing Zhang William M.Jackson Cheuk Yiu Ng Department of Chemistry University of California State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of Sciences Physical Sciences Division SRI International

The quantum yield of a VUV-induced photodissociation is defined as the ratio of the number of dissociative fragment created to the number of photons absorbed. Neutral photodissociation cross sections often remain significant for several electron volts above the ionization threshold and may be composed of contributions from both direct and indirect processes. We developed a method to measure the yield ratios of O atoms in different spin-orbital state, using VUV-VUV pump-probe lasers and the time-sliced velocity-map-imaging photoion(VMI-PI) method. Combining the quantum dissociation cross section data[1], we calculated the quantum yield for O P, P, P, D and S in VUV photodissociation of O(HП, v’=2) is 0.24(2), 0.31(2), 0.26(2), 0.38(2), 0, respectively.

关键词： superexcited oxygen quantum yield VUV photodissociation

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Ten- year follow- up investigation of stroke risk in systemic lupus erythematosus

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Stroke & Vascular Neurology 2024年第1期9卷 1-7页

作者： Jin-An Huang Ching-Heng Lin Ming-Ju Wu Yi-Hsing Chen Kuo-Cheng chang chung-Wei Hou Division of Neurology Neurological InstituteTaichung Veterans General HospitalTaichungTaiwan Department of Health Business Administration Hungkuang UniversityTaichungTaiwan Department of Medical Research Taichung Veterans General HospitalTaichungTaiwan Division of Nephrology Department of Internal MedicineTaichung Veterans General HospitalTaichungTaiwan School of Medicine Chung Shan Medical UniversityTaichungTaiwan College of Medicine National Chung Hsing UniversityTaichungTaiwan Division of Allergy Immunology and RheumatologyDepartment of Internal MedicineTaichung Veterans General HospitalTaichungTaiwan School of Medicine National Yang-Ming Chiao Tung UniversityTaichungTaiwan

Background and purpose To analyse the long-term risk of ischaemic stroke and the clinical effects of antithrombotics on the risk of haemorrhagic stroke in patients with systemic lupus erythematosus(SLE).Methods A retrospective cohort study was conducted using a population-based database taken from Taiwan National Health Insurance Research *** with SLE between 2000 and 2008 were registered and matched with two controls by the index date,age,gender and Charlson Comorbidity Index(CCI).These subjects were followed until either stroke event or 31 December *** HRs(aHRs)for strokes were estimated with Cox regression models,and the cumulative incidence of ischaemic stroke was analysed by log-rank test and Kaplan-Meier survival *** In total,8310 patients with SLE and 16620 patients without SLE were *** general,patients with SLE had higher rates of ischaemic stroke(5.4%vs 3.3%)and haemorrhagic stroke(1.5%vs 0.6%)than in *** multivariate analysis adjusted to age,gender,CCI,urbanisation level and antithrombotics uses,aHRs of all strokes,ischaemic stroke and haemorrhagic stroke were 1.73(95%CI:1.54 to 1.94),1.65(95%CI:1.45 to 1.87)and 2.24(95%CI:1.71 to 2.95),respectively,in patients with *** with SLE were significantly more likely to suffer ischaemic stroke than patients without SLE,even 10 years after SLE diagnosis(6.12%vs 3.50%,p<0.001).Antiplatelet use increased the risk of haemorrhagic stroke in SLE group(aHR=1.74,95%CI:1.18 to 2.57).Conclusions Patients with SLE are at greater risk of developing ischaemic stroke that lasts for 10 *** should be carefully administered to prevent cardiovascular events in patients with SLE due to the risk of haemorrhagic stroke.

关键词： erythematosus diagnosis likely

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Optimal sequential therapy using tyrosine kinase inhibitors as the first-line treatment in patients with metastatic renal cell carcinoma: A nationwide multicenter study

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Asian Journal of Urology 2024年第3期11卷 450-459页

作者： Jung Ki Jo Seong Il Seo MinYong Kang Jinsoo chung Cheol Kwak Sung-Hoo Hong Cheryn Song Jae Young Park chang Wook Jeong Seok Hwan Choi Sung Han Kim Eu chang Hwang Chan Ho Lee Hakmin Lee Department of Urology Medical and Digital EngineeringCollege of MedicineHanyang UniversitySeoulRepublic of Korea Department of Urology Samsung Medical CenterSungkyunkwan University School of MedicineSeoulRepublic of Korea Department of Urology National Cancer CenterGoyangRepublic of Korea Department of Urology Seoul National University HospitalSeoulRepublic of Korea Department of Urology Kangnam St Mary’s HospitalSeoulRepublic of Korea Department of Urology Asan Medical CenterSeoulRepublic of Korea Department of Urology Korea University Ansan HospitalAnsanRepublic of Korea Department of Urology Kyungpook National University HospitalDaeguRepublic of Korea Department of Urology Chonnam National University Hwasun HospitalHwasunRepublic of Korea Department of Urology Inje University Busan Paik HospitalBusanRepublic of Korea Department of Urology Seoul National University Bundang HospitalSeongnamRepublic of Korea

Objective:The purpose of the study was to identify the best sequence of therapy beginning with a tyrosine kinase inhibitor(TKI)as the first-line therapy for patients with metastatic renal cell carcinoma(mRCC)in terms of overall survival(OS),progression-free survival(PFS),and rates of discontinuation and adverse effects during the treatment ***:This is a retrospective,nationwide multicenter study of patients with mRCC after diagnosis at 10 different tertiary medical centers in Korea from January 1992 to December *** focused on patients at either“favorable”or“intermediate”risk according to the International mRCC Database Consortium criteria,and they were followed up(median 335 days).Finally,a total of 1409 patients were selected as the study *** generated a Cox proportional hazard model adjusted for covariates,and the different therapy schemes were statistically tested in terms of OS as well as *** addition,frequencies of discontinuation and adverse events were compared among the therapy ***:Of the primary patterns of treatment sequences(24 sequences),“sunitinib epazopanib”and“sunitinibeeverolimuseimmunotherapy”showed the most beneficial results in both OS and PFS with significantly lower hazards than“sunitinib”,which is the most commonly treated agent in *** that the“TKIeTKI”structure showed relatively higher discontinuation rates with higher adverse effects,the overall beneficial sequence would be“sunitinibeeverolimuseimmunotherapy”.Conclusion:Among several sequential therapy starting with TKIs,“sunitinibeeverolimuse immunotherapy”was found to be the best scheme for mRCC patients with“favorable”or“intermediate”risks.

关键词： Tyrosinekinase inhibitor Metastaticrenalcell carcinoma Overall survival Progression-free survival

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Recent developments in selective laser processes for wearable devices

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Bio-Design and Manufacturing 2024年第4期7卷 517-547页

作者： Youngchan Kim Eunseung Hwang chang Kai Kaichen Xu Heng Pan Sukjoon Hong Optical Nanoprocessing Lab Department of Mechanical EngineeringBK21 FOUR ERICA-ACE CenterHanyang University55 Hanyangdaehak-RoSangnok-GuAnsan 15588Republic of Korea Multiscale Manufacturing Lab J.Mike Walker’66 Department of Mechanical EngineeringTexas A&M UniversityCollege StationTX 77843USA State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058China

Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication *** have long been used to develop original solutions to such challenging technological problems due to their remote,sterile,rapid,and site-selective processing of *** this review,recent developments in relevant laser processes are summarized under two separate ***,transformative approaches,such as for laser-induced graphene,are *** addition to design optimization and the alteration of a native substrate,the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors,or the sequential addition of functional layers coupled with other electronic *** addition,the more conventional laser techniques,such as ablation,sintering,and synthesis,can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new ***,various wearable device components developed through the corresponding laser processes are discussed,with an emphasis on chemical/physical sensors and energy *** addition,special attention is given to applications that use multiple laser sources or processes,which lay the foundation for the all-laser fabrication of wearable devices.

关键词： Selective laser process Wearable device Transformative approach Laser-induced graphene Ablation Sintering Synthesis

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Extensions of nonlinear error propagation analysis for explicit pseudodynamic testing

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 77-86页

作者： Shuenn-yih chang Department of Civil Engineering Taipei University of Technology NTUT Box 2653 Chinese Taipei 106-08

Two important extensions of a technique to perform a nonlinear error propagation analysis for an explicit pseudodynamic algorithm （chang, 2003） are presented. One extends the stability study from a given time step to a complete step-by-step integration procedure. It is analytically proven that ensuring stability conditions in each time step leads to a stable computation of the entire step-by-step integration procedure. The other extension shows that the nonlinear error propagation results, which are derived for a nonlinear single degree of freedom （SDOF） system, can be applied to a nonlinear multiple degree of freedom （MDOF） system. This application is dependent upon the determination of the natural frequencies of the system in each time step, since all the numerical properties and error propagation properties in the time step are closely related to these frequencies. The results are derived from the step degree of nonlinearity. An instantaneous degree of nonlinearity is introduced to replace the step degree of nonlinearity and is shown to be easier to use in practice. The extensions can be also applied to the results derived from a SDOF system based on the instantaneous degree of nonlinearity, and hence a time step might be appropriately chosen to perform a pseudodynamic test prior to testing.

关键词： nonlinear error propagation explicit pseudodynamic algorithm stability condition step-by-step integration procedure step degree of nonlinearity

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Improved formulations of the CR and KR methods for structural dynamics

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Earthquake Engineering and Engineering Vibration 2018年第2期17卷 343-353页

作者： Shuenn-yih chang Department of Civil Engineering Taipei University of Technology

Although the Chen-Ricles（CR）method and the Kolay-Ricles（KR）method have been applied to conduct pseudodynamic tests,they have both been found to have some adverse numerical properties,such as conditional stability for stiffness hardening systems and an unusual overshoot in the steady-state response of a high-frequency *** improved formulation for each method can be achieved by using a stability amplification factor to boost the unconditional stability range for stiffness hardening systems and a loading correction term to eliminate the unusual overshoot in the steady-state response of a high-frequency *** details for developing improved formulations for each method are shown in this work.

关键词： conditional stability overshoot structural nonlinearity stability amplification factor loading correction term

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Selection of time step for pseudodynamic testing

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Earthquake Engineering and Engineering Vibration 2011年第3期10卷 437-451页

作者： Shuenn-yih chang Department of Civil Engineering Taipei University of Technology (NTUT)

Although the step degree of nonlinearity has been introduced to conduct basic analysis and error propagation analysis for the pseudodynamic testing of nonlinear systems, it cannot be reliably used to select an appropriate time step before performing a pseudodynamic test. Therefore, a novel parameter of instantaneous degree of nonlinearity is introduced to monitor the stiffness change at the end of a time step, and can thus be used to evaluate numerical and error propagation properties for nonlinear systems. Based on these properties, it is possible to select an appropriate time step to conduct a pseudodynamic test in advance. This possibility is very important in pseudodynamic testing, since the use of an arbitrary time step might lead to unreliable results or even destroy the test specimen. In this paper, guidelines are proposed for choosing an appropriate time step for accurate integration of nonlinear systems. These guidelines require estimation of the maximum instantaneous degree of nonlinearity and the solution of the initial natural frequency. The Newmark explicit method is chosen for this study. All the analytical results and the guidelines proposed are thoroughly confirmed with numerical examples.

关键词： pseudodynamic test nonlinear error propagation instantaneous degree of nonlinearity step degree of nonlinearity

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Nonlinear performance of classical damping

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 279-296页

作者： Shuenn-yih chang Department of Civil Engineering Taipei University of Technology

The performance of a classical damping matrix, constructed either from the use of initial structural properties or current structural properties, in the step-by-step solution of a nonlinear multiple degree of freedom （MDOF） system is analytically evaluated. The analytical results are confirmed by numerical examples. Consequently, some conclusions are drawn from these analytical results that might be considered as rough guidelines for practical applications. It is found that a classical damping matrix constructed from initial structural properties is adequate for practical applications, since it has approximately the same damping effect as obtained by current structural properties and is more efficient in terms of computing.

关键词： classical damping nonlinear dynamic analysis integration method

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