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Spatial autocorrelation calculations of the nine malignant neoplasms in Taiwan in 2005-2009: a gender comparison study

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Chinese Journal of Cancer 2011年第11期30卷 757-765页

作者： Pui-jen Tsai Center for General Education Aletheia University

Spatial analytical techniques and models are often used in epidemiology to identify spatial anomalies (hotspots) in disease regions. These analytical approaches can be used to identify not only the location of such hotspots, but also their spatial patterns. We used spatial autocorrelation methodologies, including Global Moran's I and Local Getis-Ord statistics, to describe and map spatial clusters and areas in which nine malignant neoplasms are situated in Taiwan. In addition, we used a logistic regression model to test the characteristics of similarity and dissimilarity between males and females and to formulate the common spatial risk. The mean found by local spatial autocorrelation analysis was used to identify spatial cluster patterns. We found a significant relationship between the leading malignant neoplasms and well-documented spatial risk.factors. For instance, in Taiwan, the geographic distribution of clusters where oral cavity cancer in males is prevalent was closely correspond to the locations in central Taiwan with serious metal pollution. In females, clusters of oral cavity cancer were closely related with aboriginal townships in eastern Taiwan, where cigarette smok.ng, alcohol drink.ng, and betel nut chewing are commonplace. The difference between males and females in the spatial distributions was stark. Furthermore, areas with a high morbidity of gastric cancer were clustered in aboriginal townships where the occurrence of Helicobacter pylori is frequent. Our results revealed a similarity between both males and females in spatial pattern. Cluster mapping clarified the spatial aspects of both internal and external correlations for the nine malignant neoplasms. In addition, using a method of logistic regression also enabled us to find differentiation between gender-specific spatial patterns.

关键词：空间自相关分析台湾地区恶性肿瘤性别 Logistic 逻辑回归模型空间分析技术空间格局

Development of dynamic slip model for a shear crack

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Earthquak. Engineering and Engineering Vibration 2010年第1期9卷 1-7页

作者： Juin-Fu Chai Tsung-jen Teng Center for Research on Earthquak. Engineering

The objective of this paper is to develop a dynamic slip model for a shear crack.under constant stress drop. This crack.problem is formulated by a traction boundary integral equation （BIE） in the frequency domain and then solved by the hyper-singular boundary element method as well as the regularization technique proposed in this paper. Based on the spectral integral form of the k.rnel function, the unbounded term can be isolated and extracted from the hyper-singular k.rnel function by using the method of subtracted and added back.in wave number domain. Finally, based on the inverse transformation from the frequency domain to the time domain, the time histories of crack.opening displacement under constant stress drop can be determined. Three rupture models （simultaneous rupture model, symmetric bilaterally-propagating model and unilaterally propagating model） with specified time histories of stress drop are considered in this paper. Even though these three models will cause the same final slip shapes because of the same constant stress drop, the associated slip time functions differ significantly from each other during the rupture process.

关键词： dynamic rupture model traction boundary element method (BIE) hyper-singular boundary element method (HBEM) regularization technique

Rapid recovery of rare earth elements in industrial wastewater by CuFe_2O_4 synthesized from Cu sludge

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Journal of Rare Earths 2018年第5期36卷 513-520页

作者： yao-jen Tu Cliff T.Johnston Institute of Urban Study Shanghai Normal University Shanghai 200234 China Crop Soil and Environmental Sciences Purdue University 915 W. State Street West Lafayette IN 47907 USA

This study systematically evaluates the recovery of rare earth elements（REEs） from aqueous solution and industrial wastewater using magnetic nanoparticles CuFe2O4. The industrially manufactured CuFe2O4 displays a nonlinear isotherm for REEs adsorption, suggesting limiting binding sites on the CuFe2O4 surface. The recovery of REEs increases significantly from 0.1% to 99.99% with increasing pH（2.29-8.15）. At room temperature, the maxima recovery rates of Nd, La, and Ce are observed to be in a high capacity of 51.02, 42.02, and 40.16 mg/g, respectively. No significant attenuation of REE adsorption is observed with increasing NaCl concentration from 0.001 to 1.0 mol/L, showing high selectivity of REEs even in such high NaCl concentration matrix. In addition, desorption efficiency increases with the increasing concentration of HNO3 in the range of 0.005-0.05 mol/L. When HNO3 concentration is over 0.05 mol/L, the desorption efficiency can reach almost 100% in each batch experiment. Importantly, our results show that REEs can be sorbed and recycled from liquid crystal display（LCD） polishing wastewater, suggesting that CuFe2O4 may be a good candidate in the efficient and rapid recovery of REEs from industrial wastewater.

关键词： Rare earth elements Industrial wastewater Industrial sludge Magnetic separation CuFe2O4

Ring columns as pier scour countermeasures

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International Journal of Sediment Research 2011年第3期26卷 353-363页

作者： jen-Hao CHENG Han-Peng SHIH jen-Wei CHANG Candidate in Program of Civil and Hydraulic Engineering Feng Chia UniversityTaichungTaiwanChina Department of Water Resources Engineering and Conservation The University of Feng ChiaTaiwan.China

Ring columns placed upstream of a bridge pier to protect it from local scouring are typical scouring countermeasures.A series of experiments are conducted under clear-water steady flow（V/V;≤1）with uniform *** parameters,such as ring column diameter,thick.ess,height,and distances between ring columns and the pier,are considered in the *** data are used to assess the influence of each parameter on pier scour *** results indicate that pores in ring columns provide space for energy dissipation of the downflow,hence,effectively reduce the flow energy impacting the downstream *** friction force of ring columns caused by their geometric shape reduces k.netic energy and pier scour *** general,it is found that the best pattern of ring columns reduce pier scour depth by 65%.

关键词： Ring columns Local scour Energy dissipation Scour depth

Uniform positivity of Lyapunov exponent for a class of smooth Schrodinger cocycles with weak.Liouville frequencies

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Frontiers of Mathematics in China 2017年第3期12卷 607-639页

作者： Jinhao LIANG Po-jen k.NG Department of Mathematics Nanjing University Nanjing 210093 China Department of Applied Mathematics Chiao Tung University Hsinchu 30010 Taiwan China

We prove uniform positivity of the Lyapunov exponent for quasiperiodic SchrSdinger cocycles with C2 cos-type potentials, large coupling constants, and fixed weak.Liouville frequencies.

关键词： Lyapunov exponent C2 cos-type potential weak.Liouville frequency

Design of a long range nano-scale resolution mechanism

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第4期11卷 250-254页

作者： Shuo Hung CHANG jen Bon LEE Department of Mechanical Engineering National Taiwan University

This paper presents the development of a coarse-fine dual precision positioning stage to achieve long travel range and high *** fine stage is arranged in series with a coarse *** k.y in the fine stage design is the choice of a toggle mechanism for a tight mechanical loop with high stiffness and *** designed the toggle mechanism for reduction of the displacement to suppress signal *** performance of the coarse and fine stages was verified with an optical encoder and capacitive sensor,*** measurement results show that the dual mechanism has a travel range of 1 mm and resolution of 30 nm.

关键词： Coarse-fine dual stage Nano-scale resolution Piezoelectric (PZT) actuator

An efficient stochastic algorithm for mid-term scheduling of cascaded hydro systems

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 163-173页

作者： Xiaolin GE Shu XIA Wei-jen LEE Electric Power College Shanghai University of Electric Power Shibei Electricity Supply Company of State Grid Shanghai Municipal Electric Power Company Energy Systems Research Center University of Texas at Arlington

Due to the stochastic and correlated attributes of natural inflows, the mid-term generation scheduling problem for cascaded hydro systems is a very challenging *** paper proposes a novel stochastic optimization algorithm using Latin hypercube sampling and Cholesk. decomposition combined with scenario bundling and sensitivity analysis(LC-SB-SA) to address this *** deal with the uncertainty of natural inflows, Latin hypercube sampling is implemented to provide an adequate number of sampling scenarios efficiently, and Cholesk. decomposition is introduced to describe the correlated natural inflows among cascaded *** addition, to overcome the difficulties in solving the objectives of all the scenarios, scenario bundling and sensitivity analysis algorithms are developed to improve the computational *** results from both two-station and tenstation systems indicate that the proposed method has the merits in accuracy as well as calculation speed for the midterm cascaded hydro generation *** consideration of natural inflow correlation mak.s the formulated problem more realistic.

关键词： Cascaded hydro systems Mid-term scheduling Stochastic optimization algorithm Correlation Sensitivity

Analytical modeling for colloid-facilitated transport of N-member radionuclides chains in the fractured rock

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Nuclear Science and Techniques 2007年第6期18卷 336-343页

作者： TIEN Neng-Chuan jen Chun-Ping Energy and Environment Research Laboratories Industrial Technology Research Institute Hsinchu 310 Taiwan Department of Mechanical Engineering National Chung Cheng University Chia Yi 62102 Taiwan

A precious analytical model for N-member radionuclide decay chains has been extended to include the ef- fect of radionuclide sorption with groundwater *** distribution coefficients were employed in the nu- clide decay chain to illustrate the present *** colloid concentration was assumed constant in time and space owing to equilibrium between colloid generation and sedimentation by chemical and/or physical ***- thermore,the diffusion of colloids into the rock.matrix was ignored because the diameter of colloid is relatively large and colloids and fracture surfaces are *** results indicated that colloids could facilitate the transport of radionuclides and the large adsorbability of nuclides with colloids enlarged the effect of acceleration by *** influence of colloids on the radionuclide transport was expected to be crucial to the actinides with large adsorbability; however,the present results revealed that the low-adsorbing nuclides whose parent nuclides have large capability of sorption could be also facilitated significantly by colloids ***,the role of colloids played in the transport of the radionuclides decay chain should be assessed carefully in the radioactive waste *** analyti- cal method presented herein is helpful to verify/validate further complex far-field models.

关键词：分析模型放射性核素氮元素同位素

The model developed for stress-induced structural phase transformations of micro-crystalline silicon films

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Nano-Micro Letters 2010年第2期2卷 68-73页

作者： Chang-Fu Han jen-Fin Lin Department of Mechanical Engineering National Cheng k.ng University Center for Micro/Nano Science and Technology National Cheng k.ng University

The nanoindentations were applied to island-shaped regions with metal-induced Si crystallizations. The experimental stress-strain relationship is obtained from the load-depth profile in order to investigate the critical stresses arising at various phase transitions. The stress and strain values at various indentation depths are applied to determine the Gibbs free energy at various phases. The intersections of the Gibbs free energy lines are used to determine the possible paths of phase transitions arising at various indentation depths. All the critical contact stresses corresponding to the various phase transitions at four annealing temperatures were found to be consistent with the experimental results.

关键词： Silicon films Phase transitions Stress-strain model