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面板堆石坝变形监测研究(英文)

岩土工程学报 2008年第11期30卷 1651-1656页

作者： Anna Szostak-chrzanowski DENG Nian-wu LI Min Michel Massiera Canadian Centre for Geodetic Engineering University of New Brunswick Canada State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China Faculte d'ingenierie (genie civil) Universite de Moncton Canada

面板堆石坝的安全依赖于良好的设计、施工和在大坝施工及运行期的实时监测,土工监测技术和测绘技术可以用来监测大坝位移,并对大坝的非正常变形提供预警。面板堆石坝一般在施工期和蓄水期会发生较大变形:在施工期,堆石体和上游面板会因... 详细信息

面板堆石坝的安全依赖于良好的设计、施工和在大坝施工及运行期的实时监测,土工监测技术和测绘技术可以用来监测大坝位移,并对大坝的非正常变形提供预警。面板堆石坝一般在施工期和蓄水期会发生较大变形:在施工期,堆石体和上游面板会因为自重而相互积压发生变形;在蓄水期,堆石体和上游面板会在水压力的作用下发生变形。为了保证面板的整体性和大坝安全,特别要防止面板的变形超过其最大允许变形。由于对筑坝材料参数的不完全可知性和计算理论的不完善,必须对大坝及其周边变形进行严密监测以预防大坝发生较大变形。应用有限元方法对中国某面板堆石坝位移变化进行研究。

关键词：面板堆石坝位移分析有限元安全监测

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变形模型可区分度量

测绘学报 1993年第1期22卷 19-24页

作者：陈永奇 A.chrzanowski 武汉测绘科技大学

在监测网设计阶段，变形体的变形特性一般不是完全清楚。因此，设计的监测方案应当能有效地和足够灵敏地区分几种可能的模型。本文研究了模型的可区分度量，所用的方法具有思路明确、清晰等特点，特别适用于在设计阶段设置指标。文中通... 详细信息

在监测网设计阶段，变形体的变形特性一般不是完全清楚。因此，设计的监测方案应当能有效地和足够灵敏地区分几种可能的模型。本文研究了模型的可区分度量，所用的方法具有思路明确、清晰等特点，特别适用于在设计阶段设置指标。文中通过一个模拟网的分析和讨论，说明采用模型可区分度量作为设计准则的必要性。分析的结果还和Forstner法所得的结果进行初步的比较。

关键词：监测网设计变形模型可区分度量

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Effect of Temperatures on Polymerization Stress and Microleakage of Class V Composite Restorations

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Open Journal of Composite Materials 2013年第4期3卷 107-112页

作者： Pavinee Padipatvuthikul Didron Wojciech chrzanowski Ayman Ellakwa Department of General Dentistry Srinakharinwirot University Bangkok Thailand

The loss of interfacial integrity was identified as one of the major causes for replacement of resin composite restorations. Preheating procedure has been proven to enhance flowability and adaptation of resin composites and increase their degree of conversion. The purpose of this study was to investigate polymerization contraction stress produced in resin composites after preheating to 37℃ and 60℃, and measure microleakage of Class V restorations restored with preheated composites. Three resin composites (GC Kalore, Gradia Direct X, Filtek Supreme XT) at room temperature, 37℃, and 60℃ were investigated. Maximum contraction stress of the composites (n = 5) was evaluated in a modified low-compliance device. Samples were light-cured for 40 seconds and the maximum force was recorded during 15 minutes. Calculations were done to adjust for the system’s compliance and obtain linear shrinkage values of composites. Data were analyzed by Multivariated Analysis of Variance (MANOVA) and Tukey’s test for multiple comparisons (α = 0.05). Seventy-two Class V cavities were prepared on the buccal surfaces of extracted premolars and divided into 9 groups. The teeth were restored with composites at 3 temperatures and were thermo-cycled between 5℃ and 55℃ with a one-minute dwell-time for 1000 cycles. The teeth were sealed with wax and nail vanish before placed in 0.5% toluidine blue dye for 24 hours. The teeth were embedded in self-curing resin and sectioned bucco-lingually with a slow-speed diamond saw, providing 3 sections per restoration. Microleakage was rated by two evaluators using a 0 - 4 ordinal scale at the occlusal and cervical margins under light microscope. Microleakage data were analyzed with Kruskal-Wallis ANOVA and Mann-Whitney U test (α = 0.05). Results indicate that preheating composites to 37℃ and 60℃ significantly increased polymerization contraction stress of composites (p 0.05). A significantly greater amount of leakage was found at the cervical margins (p 0.05). F

关键词： Preheating Dental Composite Polymerization Shrinkage Contraction Stress Microleakage

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激光在精密水准测量中的应用(加拿大)

工程勘察 1974年第2期 77-86页

作者： Adam chrzanowski Hands-Dirk Janssen 陈不锈一机部勘测公司

前言一等大地测量和有些工业方面的测量如敏感的工程结构的变形观测对水准测量要求尽可能高的精度,几年来水准测量的精度和误差传递已成为很多调查研究的主题。但对水准测量精度的确定和分级仍有些问题需用现代技术和方法去解决。通常,... 详细信息

前言一等大地测量和有些工业方面的测量如敏感的工程结构的变形观测对水准测量要求尽可能高的精度,几年来水准测量的精度和误差传递已成为很多调查研究的主题。但对水准测量精度的确定和分级仍有些问题需用现代技术和方法去解决。通常,对于有平行玻璃板测微器的光学水准仪可望能达到每公里1毫米的测量误差,如野外作业中适当注意还可能更好些。这一精度通常认为是一等精密水准测量规范的依据。

关键词：水准测量精度仪器水堆激光束检测器标准误差高程测量莱塞光束检测仪器中误差激光激光水准仪系统误差

Skin 11β-hydroxysteroid dehydrogenase type 1 enzyme expression regulates burn wound healing and can be targeted to modify scar characteristics

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Burns & Trauma 2023年第1期11卷 32-45页

作者： Kevin H.-Y.Tsai Huaikai Shi Roxanne J.Parungao Sina Naficy Xiaotong Ding Xiaofeng Ding Jonathan J.Hew Xiaosuo Wang Wojciech chrzanowski Gareth G.Lavery Zhe Li Andrea C.Issler-Fisher Jun Chen Qian Tan Peter K.Maitz Mark S.Cooper Yiwei Wang Adrenal Steroid Group ANZAC Research InstituteConcord HospitalThe University of SydneySydneyNSW 2137Australia Burns and Reconstructive Surgery Research Group ANZAC Research InstituteConcord HospitalThe Uni-versity of SydneySydneyNSW 2137Australia School of Chemical and Biomolecular Engineering The University of SydneySydneyNSW 2006Australia Jiangsu Provincial Engineering Research Centre of TCM External Medication Development and Application Nanjing University of Chinese MedicineNanjingJiangsu210023China Department of Burns and Plastic Surgery Nanjing Drum Tower Hospital Clinical CollegeNanjing University of Chinese MedicineNanjingJiangsu210008China Heart Research Institute The University of SydneySydneyNSW 2006Australia Sydney Nano Institute Sydney Pharmacy SchoolFaculty of Medicine and HealthThe University of SydneySydneyNSW2006Australia Department of Biosciences Centre for Healthy Ageing and Understanding DiseaseNottingham Trent UniversityNG14BUUK Burns and Reconstructive Surgery Unit Concord Repatriation General HospitalSydneyNSW 2137Australia

Background:Excessive scarring and fibrosis are the most severe and common complications of burn *** exposure to high levels of glucocorticoids detrimentally impacts on skin,leading to skin thinning and impaired wound *** can generate active glucocorticoids locally through expression and activity of the 11β-hydroxysteroid dehydrogenase type 1 enzyme(11β-HSD1).We hypothesised that burn injury would induce 11β-HSD1 expression and local glucocorticoid metabolism,which would have important impacts on wound healing,fibrosis and *** additionally proposed that pharmacological manipulation of this system could improve aspects of post-burn ***:Skin 11β-HSD1 expression in burns patients and mice was *** impacts of 11β-HSD1 mediating glucocorticoid metabolism on burn wound healing,scar formation and scar elas-ticity and quality were additionally examined using a murine 11β-HSD1 genetic knockout ***-release scaffolds containing therapeutic agents,including active and inactive glucocorticoids,were developed and pre-clinically tested in mice with burn ***:We demonstrate that 11β-HSD1 expression levels increased substantially in both human and mouse skin after burn injury.11β-HSD1 knockout mice experienced faster wound healing than wild type mice but the healed wounds manifested significantly more collagen deposition,tensile strength and stiffness,features characteristic of excessive *** of slow-release prednisone,an inactive glucocorticoid,slowed the initial rate of wound closure but significantly reduced post-burn scarring via reductions in inflammation,myofibroblast generation,collagen production and scar ***:Skin 11β-HSD1 expression is a key regulator of wound healing and scarring after burn *** of an inactive glucocorticoid capable of activation by local 11β-HSD1 in skin slows the initial rate of wound closure but significantlyimproves scar characteristics po

关键词： Wound healing Burn injury Scarring Skin 11β-HSD1 11β-HSD1 knockout Glucocorticoid metabolism Polycaprolactone scaffold Drug delivery