WorldWideScience

Sample records for bridge anchorages

  1. Study on Fatigue Behavior of Anchorage of Cable and Girder of Long Span Cable-Stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A full scale model test is done and a FEM model is established toinvestigate the fatigue behavior of the Nancha cable-stayed bridge of the Nanjing Second Yangtz River Bridge, a long span steel bridge with a main span of 628 m. The results of test and FEM are analyzed and compared. It is shown that they are in good agreement. It is verified that the fatigue characteristic of the anchorage structure of cable and girder of the bridge satisfies the requirements specified by Chinese, British and American codes.

  2. A Study of the system control model of caisson dewatering of the north anchorage of Taizhou Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhao Yanrong; Zhou Zhifang; Ruan Jing

    2011-01-01

    A caisson foundation is applied to the north anchorage of Taizhou Yangtze River Highway Bridge of which the initial caisson sinking requires dewatering. Since the caisson foundation is quite close to nearby buildings, a system control model is established with source (sink) distribution and intensity being the object function, minimum requirements of settlement and deformation of surroundings caused by dewatering and dynamic water levels during different working procedures being constraints, and the design parameter of pumping wells being the variable, so as to lower the jeopardizing of surrounding buildings, which provides a new method for active control over settlement during dewatering. Such a method of dewatering based on system control model should be of significance for similar projects involving dewatering.

  3. On-site tests to estimate aquifer permeability of drainage area of south caisson anchorage construction of Taizhou Bridge

    Institute of Scientific and Technical Information of China (English)

    Feng Zhaoxiang; Zhao Yanrong

    2011-01-01

    During the construction of the south caisson anchorage of Taizhou Bridge, the drainage area is located in the lower reaches of the Yangtze River and the permeability of stratums there is considerable. In order to maintain progress and guarantee safety during the sinking of the caisson, water should be drained in the initial period. Subsequently, detailed information about the aquifer permeability is required to make sure that the drainage will proceed successfully,which consequently necessitates the on-site estimation of the aquifer permeability in the drainage area. Therefore, the traditional pumping test and slug test are implemented respectively on site. The comparison of computational results of these two tests indicates that they are consistent overall. Notwithstanding, as slug test can be conducted with portable facilities in a short time and the manipulation is easy and few people need to be involved, the advantages of slug test is conspicuous compared with the traditional pumping test. It could be speculated that slug test will gain a prevalent application in the measurement of aquifer permeability in the future.

  4. Anchorage Areas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An anchorage area is a place where boats and ships can safely drop anchor. These areas are created in navigable waterways when ships and vessels require them for...

  5. 铁路悬索桥大吨位隧道锚承载性能分析%Analysis on Bearing Performance of Large-tonnage Tunnel-type Anchorage of Railway Suspension Bridge

    Institute of Scientific and Technical Information of China (English)

    江南; 冯君

    2013-01-01

    丽香铁路金沙江大桥是我国首座采用大吨位隧道式锚碇的铁路悬索桥.本文采用三维弹塑性有限元方法对隧道锚的变形机理、承载能力以及围岩稳定状态进行分析.研究结果表明:在正常缆力作用下,锚碇体及周围岩体的位移均处于毫米量级,远小于悬索桥塔顶允许位移;锚碇体整体表现为以前底板为支点,锚碇体后部向上转动和整体向前滑移的变形模式;锚碇体及围岩绝大部分处于三向受压状态,只是在锚碇底端与下部围岩的接触部分,以及顶拱与边墙交界处局部范围内存在拉应力,建议在这些部位采取措施重点加强;基于超载极限分析法计算得到锚碇体的整体抗滑安全系数在9以上.有限元分析结果为铁路悬索桥隧道锚的优化设计提供了理论依据.%The Jinsha River Bridge of the Lijiang-Xianggelila Railway is the first railway suspension bridge with tunnel type anchorages of large tonnage in China.By using the three dimensional elastoplastic finite element method,the deformation mechanism & bearing capacity of the tunnel anchorage and the stability of surrounding rock were analyzed.The results show as follows:Under the action of normal cable forces,the displacements of the anchorage body and surrounding rock are in the millimeter range,which are far less than the allowable displacements of the suspension bridge tower;the deformation mode of the anchorage body includes the back part of the anchorage body turning upward with the front bottom plate as the fulcrum and the whole anchorage body sliding forward; most parts of the anchorage body and surrounding rock are in the triaxial compression state,except that the contact surface between the bottom end of the anchorage body and the under surrounding rock and,the local boundary area between the crown hog and flank wall are subjected to tensile stresses where stressed strengthening is needed;with the overload limit analysis method

  6. 国内大跨径悬索桥锚碇锚固系统比较研究%The Compare and Investigation of Anchor System for Anchorage of Domestic Long-Span Suspension Bridge

    Institute of Scientific and Technical Information of China (English)

    李海; 鲜亮; 姚志安

    2011-01-01

    The anchor system for anchorage of suspension bridge plays an important controlling role in overall safety of structure . The paper mainly compares the different anchor system for anchorage of domestic long-span suspension bridge, and Makes an investigation on durability 、reliability and economy, which can be used for reference on adoption for future anchor system for anchorage of long-span suspension bridge.%悬索桥锚碇锚固系统在保证结构整体安全上具有重要控制作用.主要对我国目前大跨径悬索桥锚固系统不同体系作了比较,并对各种体系的耐久性、可靠性及经济性等方面进行了研究,为今后大跨径悬索桥锚固系统体系的采用提供了借鉴.

  7. Design of cable-girder anchorage system scheme in self-anchored suspension bridge%自锚式悬索桥缆-梁锚固系统方案设计

    Institute of Scientific and Technical Information of China (English)

    凌云

    2015-01-01

    本文根据已建以及待建自锚式悬索桥工程实例,将自锚式悬索桥工程中主缆在加劲梁梁端的锚固方案进行了总结分析,从施工方面、经济性以及美观性等方面指出了各种锚固方式的优缺点以及适应性。按照锚体材料的不同将现有锚固方式重新进行了分类,综合现有的分类方式提出了一套锚固系统方案设计流程。这种设计流程条理清楚、直观易理解,为今后的自锚式悬索桥主缆锚固系统设计提供指导,快速的形成锚固系统方案,提高设计效率,并获得更好的经济性和美观性。%According to the engineering examples of the self -anchored suspension bridges built and to be built , the cable -girder an-chored projects are summarized and analyzed.From the construction , economy and aesthetics aspects , the advantages adaptability of vari-ous ways of anchoring and are pointed out.According to the different materials of the existing anchorage , the way of anchoring is re -clas-sified and a set of anchor system design process is put forward based on the classification of the existing anchorage systems .This design process is clear , intuitive and easy to understand and can provide guidance for the design of self -anchored suspension bridge main cable anchorage system in the future.Using this design process , anchorage system scheme will be quickly put forward , the design efficiency can be improved and the bridge will be more economic and more beautiful.

  8. Study of Mechanical Behavior and Ultimate Carrying Capacity of Suspender Anchorage Zone in Axial Direction of Bridge%顺置式吊杆锚固区受力特性与极限承载力研究

    Institute of Scientific and Technical Information of China (English)

    高小妮; 贺拴海; 齐宏学

    2012-01-01

    To have an understanding of the mechanical behavior and ultimate carrying capacity of suspender anchorage zone set in the axial direction of bridge under the action of suspender forces, a combined cable-stayed and self-anchored suspension system bridge that was being constructed was cited as an example, the software ANSYS was used to set up the spatial shell finite element model, the mechanical behavior of the anchorage zone under the action of the worst load was studied, the ultimate carrying capacity of the anchorage zone was analyzed, respectively u-sing the linear elasticity and nonlinearity analysis methods and the force conditions of the components in the anchorage zone were discussed. The results of the study show that under the action of the worst load, the stress in the steel anchor box and steel anchor beam is less than that in the diaphragm. With the exception that the stress concentration in the welding of the steel anchor beam and diaphragm is notable, the stress distribution in all components is uniform and the deformation of the components in the axial direction of the bridge is great. The results of the different analysis methods for the ultimate carrying capacity also show that when the ultimate carrying capacity of such type of the structure is analyzed, using the shell element model, the material nonlinearity should considered only and in the design of the structure, it is proposed that adequate attention should be paid to the problem of insufficient rigidity of the diaphragm.%为掌握顺桥向设置的吊杆锚固区在吊杆力作用下的受力特性和极限承载力,以某在建斜拉—自锚式悬索组合体系桥为依托工程,利用ANSYS软件建立壳单元空间有限元模型,对锚固区在最不利荷载作用下的受力性能进行研究;并分别采用线弹性及非线性分析方法对吊杆锚固区极限承载力进行分析,讨论构件的受力情况.结果表明:在最不利荷载作用下,钢锚箱及钢锚梁

  9. TERRAIN, Anchorage, Alaska

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Anchorage AOI consists of seven areas. These areas were to be collected to the 'highest' accuracy requirement. Ground Control is collected throughout the AOI for...

  10. Onplant-supported orthodontic anchorage.

    Science.gov (United States)

    Armbruster, P C; Block, M S

    2001-03-01

    The use of onplant-supported orthodontic anchorage is still in its early stages. The concepts presented in this article have tried to stress the importance of anchorage control in orthodontic cases, some problems associated with traditional means to augment orthodontic anchorage, the rationale for developing a skeletal anchorage unit based on endosseous implant technology, and the effectiveness of the onplant as an anchorage unit. Cephalometric superimpositions are most likely the best method to determine the effectiveness of the onplant's contribution to anchorage control and have been included here to that end. Further research into its effectiveness may broaden the use of onplants in future orthodontic cases.

  11. 斜拉桥索塔锚固区前壁竖向拉-压杆模型%Vertical STM in Facade Wall of Pylon Anchorage Zone of Cable-stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    陶齐宇; 刘扬

    2011-01-01

    To the tendon anchorage system in the wall of box pylon of cable-stayed bridge, the facade wall of cable-anchored pylon was researched using strut-and-tie model ( STM). According to the optimization principle of STM, the STM of single anchor was established by means of force method. On the basis of the STM of single anchor, the STM in the facade wall was preliminary built. The expression of internal force in ties about z, the vertical distance between the tie T3 and node 1, was established. Using topology optimization result (T2 = 0) and Cardan Formula, the value of z was determined, the STM in the facade wall was comprehensively solved. Thus, the distribution of compressive and tensile stresses in the facade wall under the action of vertical component of cable force was accurately reflected. Finally, through researching the pylon of Yibin Yangzte River Bridge, the parameter α3 =23.3° was proposed, and the STM in the facade wall was simplified. It has better precision and can be used to determine tendon specification in the anchorage zone of box pylon.%对斜拉桥箱形截面索塔塔壁预应力锚固体系,采用拉-压杆模型方法对拉索直接锚固的塔柱前壁进行研究.以力法为手段,依据拉-压杆模型的优化原理,确立了体内单锚的拉-压杆模型.以单锚拉-压杆模型为基础,初步构建前壁的拉-压杆模型.取z为拉杆(T3)与结点(1)间的竖向距离,采用力法建立以z为函数的拉杆内力的表达式,利用拓扑优化成果(T2=0)和卡尔丹公式,确定z的数值,自下而上全面解答了前壁的拉-压杆模型,从而准确反映在拉索竖向分力作用下前壁拉、压应力的分布状况.最后,通过对宜宾长江大桥索塔的实例研究,提出α3= 23.3°,简化了前壁拉-压杆模型,且具有较好的工程精度,可用于确定索塔锚固区的预应力筋的规格.

  12. 武汉鹦鹉洲长江大桥北锚碇新型沉井基础设计%Design of New Type Caisson Foundation for North Anchorage of Yingwuzhou Changjiang River Bridge in Wuhan

    Institute of Scientific and Technical Information of China (English)

    李明华; 杨灿文

    2011-01-01

    The main bridge of Yingwuzhou Changjiang River Bridge in Wuhan is a three-tower and four-span suspension bridge. After comparison of different design proposals, it was determined that a new type caisson structure of circular cross section and with multiple round wells would be used for the north anchorage foundation of the bridge. In the big size well in the center of the caisson, the crisscross diaphragm was set and along the periphery within the caisson, a number of small size wells were uniformly set. The caisson is 43 m high and has totally 8 lifts, of which the first lift is a steel shell concrete caisson and the rest parts of the caisson from the second to the eighth lifts are all of reinforced concrete caissons. In the construction of the caisson, the caisson was sunk down by no dewatering and the air curtain was provided in the caisson wall to reduce sinking difficulty and construction risk. The software FLAC3D was used to conduct numerical simulation and analysis of the construction process of the sinking and to evaluate the construction safety, the environmental effect caused by the construction and the deformation of the foundation to be applied with load after the bridge was put into operation. The results of the a-nalysis show that in the process of sinking the caisson in lifts, the caisson structure and ground deformation can meet the relevant requirements in the codes and the adverse influence of the construction on the ambient buildings and the river dyke can be effectively avoided.%武汉鹦鹉洲长江大桥主桥为三塔四跨悬索桥.该桥北锚碇基础经多方案比选采用多圆孔环形截面新型沉井结构.沉井中间大圆孔内设置十字形隔墙,圆环内沿圆周均布有小直径井孔.沉井总高43 m,共分8节,第1节为钢壳混凝土沉井,第2~8节均为钢筋混凝土沉井.北锚碇施工中采用不排水下沉、井壁增加空气幕等措施减小施工难度及风险.采用软件FLAC3D对沉井施工过程进

  13. Experimental Study of Anchor Tensile Plate Cable Anchorage System in Concrete Girder of Actual Bridge%锚拉板式混凝土索梁锚固体系实桥试验研究

    Institute of Scientific and Technical Information of China (English)

    石雪飞; 周军勇; 胡可; 阮欣

    2016-01-01

    为研究索力作用下锚拉板式混凝土索梁锚固体系的受力性能,以五河淮河大桥为工程背景进行实桥试验和有限元分析。选取该桥0号节段混凝土锚拉板进行实桥试验,测试锚拉板在分级索力作用下的应力及变形,采用ANSYS软件建立有限元模型,计算2种连接方式下(考虑混凝土主梁与钢锚拉板的固结与滑移)的应力分布与锚拉板变形。结果表明,钢锚拉板与混凝土主梁在固结或滑移连接方式下,斜拉索锚固区域的应力分布基本相同,但连接区域的应力分布及锚拉板变位差别显著;测试的锚拉板应力和位移与荷载呈现良好线性相关性,最大测点应力296 M Pa ,结构仍处于弹性工作状态;锚拉板应力分布的实测值与有限元计算值吻合,板件应力扩散和传递效果良好;连接区域的实测应力和位移与滑移方式下的有限元分析较吻合,但摩擦系数不主导滑移结果。%To study the mechanical performance of the anchor tensile plate cable anchorage system in concrete girder under the action of the cable tension ,the test and finite element analysis of the steel anchor tensile plate stay cable anchorage system in the concrete main girder of the actu‐al bridge of Wuhe Huaihe River Bridge were carried out .The anchor tensile plate in the segment No .0 of the main girder of the bridge was selected and tested .The stress and displacement of the anchor tensile plate under the different levels of the stay cable tension were measured .The finite element model for the anchor tensile plate was set up ,using the software ANSYS and the stress distribution and the anchor tensile plate displacement under the 2 kinds of the connecting ways (the rigid fixity and sliding connecting of the anchor tensile plate with the concrete main girder ) were calculated .The results show that under the connecting ways of the rigid fixity or sliding connect‐ing of the anchor

  14. Measuring the democratic anchorage of governance networks

    DEFF Research Database (Denmark)

    Fotel, Trine; Sørensen, Eva; Torfing, Jacob

    in what we shall call a model for the democratic anchorage of governance networks. As illustrated by our qualitative case study of a multi-level and cross-border governance network involved in the recent decision to build a bridge between Denmark and Germany, the democratic anchorage model helps to assess......There has been a growing debate about the democratic problems and potentials of governance networks among political scientists and public managers. While some claim that governance networks tend to undermine democracy, others argue that they have the potential to improve and strengthen democracy....... This debate is found wanting in two respects. First of all, there has been far too little discussion about what democracy means in relation to pluricentric governance networks. Second, the current debate builds on the assumption that it is possible to give a clear-cut answer to the question of the democratic...

  15. 荆岳长江公路大桥索塔锚固钢锚梁结构体系分析%Analysis of Steel Anchor Beam Structural System of Anchorage in Pylon of Jingyue Changjiang River Highway Bridge

    Institute of Scientific and Technical Information of China (English)

    张家元; 丁望星; 朱世峰

    2015-01-01

    荆岳长江公路大桥主桥为主跨816 m的双塔不对称混合梁斜拉桥,在成桥状态下,索塔锚固采用两端固定的钢锚梁结构体系。为研究钢锚梁平衡斜拉索索力的作用,验证超静定结构体系钢锚梁的合理性,采用ANSYS软件建立索塔锚固区有限元模型,分析钢锚梁施工过程中2种不同的支承体系方案,并通过足尺模型试验研究钢锚梁对斜拉索索力的分配比例。结果表明:斜拉索初张时采用边跨固定、中跨滑动,斜拉索张拉后两端固定结构体系的钢锚梁承担了斜拉索索力水平分力的83.7%,钢锚梁与塔壁对索力水平分力的分配比例为8∶2,该体系能够发挥钢锚梁平衡斜拉索索力的作用,且结构可靠度高。%The main bridge of Jingyue Changjiang River Highway Bridge is a asymmetric span hybrid girder cable‐stayed bridge with double pylons and with a main span of 816 m .The anchor‐age in a pylon of the bridge in completion state is of the steel anchor beam structural system with its two ends being fixed .To study the function of the anchor beam balancing the stay cable forces and to verify the rationality of the anchor beam of the statically indeterminate structural system , the software ANSYS was used to set up the finite element model for the anchorage in the pylon , 2 different support schemes adopted for construction of the anchor beam were analyzed and the ra‐tios of the stay cable forces distributed by the anchor beam were studied by means of the full‐scale model tests .The results of the study show that the anchor beam using the structural system with its side span end being fixed ,its central span end being slide at the time of initial tensioning of the stay cables and with its two ends being fixed after tensioning of the stay cables can bear 83 .7%horizontal component of the stay cable forces and the ratio of the horizontal component distributed by the anchor beam and pylon wall

  16. 南京长江四桥北锚碇工程锚体及锚固系统施工技术%Construction Technology of Anchor and Anchor System for North Anchorage Engineering of the Fourth Nanjing Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    葛文璇; 徐贵娥; 陈静

    2012-01-01

    悬索桥的锚碇是一个十分重要的部位,以南京长江四桥北锚碇工程为背景,介绍了锚体及锚固系统的施工工艺.南京长江四桥锚碇锚固系统采用钢筋混凝土榫锚固系统,以提高结构的可靠性和耐久性.从锚体的分层分块、模板施工和混凝土浇筑工艺方面介绍了锚体施工工艺,并从锚固钢板的加工、起吊、安装、精确定位等方面介绍了锚固系统的施工工艺.%The anchorage caisson is a very important part of suspension bridge. The authors introduce the construction technology of anchor and anchor system of north anchorage of the Fourth Nanjing Yangtze River Bridge. The mortise-tenon anchor system of reinforced concrete is adopted in the anchor system of north anchorage of the Fourth Nanjing Yangtze River Bridge in order to improve its reliability and durability. The authors introduce the construction technology of anchor from anchor of hierarchical blocks, formwork and concrete pouring technique. From the anchor plate processing, hoisting, installation and precise positioning, the author introduce the construction technology of anchor system.

  17. 南京长江四桥南锚碇基坑渗流控制方案研究%Study on Seepage Control Scheme for Foundation Pit of South Anchorage of 4th Nanjing Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    肖利; 王连新; 潘霄; 张家发

    2009-01-01

    The foundation pit for the south anchorage of 4th Nanjing Yangtze River Bridge is protected with concrete diaphragm wall. The wall will be embedded in the medium-weathered layer with 3 meters. Because the dredging layer at the wall bottom and the strongly weathered rock are more permeable than the wall, under-ground water may flow through the dredging layer to the foundation pit. On the basis of numerical simulation with 3D seepage field model, the permeability sensitivity is analyzed and the seepage control efficiency is compared among different designs. The results indicate that the thickness and permeability of medium-weathered layer influence the discharge and seepage stability of the pit significantly, that under cases without curtain grouting in the bed-rock, the seepage gradient in the dredging layer is high and seepage deformation might occur, and that under cases with curtain grouting , the discharge would be much lower and the stability of foundation pit would be ensured.%南京长江第四大桥南锚碇基础采用井筒式地连墙结构形式,地连墙嵌入中风化层约3m,下部可能形成沉渣层,且强风化层裂隙较多,局部透水性较好,地下水可能通过沉渣层及裂隙绕渗进入基坑.建立三维模型模拟基坑渗流场,通过参数敏感性分析和方案对比表明:中风化层厚度及渗透性对基坑的渗流量及渗透稳定性有明显影响;基岩无灌浆帷幕条件下,地连墙底面沉渣层渗透比降过大,可能引发渗透变形问题;对基岩进行帷幕灌浆后,可有效减小基坑渗流量,使基坑渗透稳定性得到保障.

  18. New concept of physiologic anchorage control

    Directory of Open Access Journals (Sweden)

    Tian-Min Xu

    2015-01-01

    Full Text Available Molar anchorage loss in extraction case is believed due to the reaction of mechanical force applied to retract anterior teeth. While it may be close to truth in adult patients, it is certainly not true in adolescents. Studies on molar growth show upper molar move forward as mandible growing forward, probably through intercuspation force. Hence, for adolescents, molar anchorage loss shall consist of two parts. One is from retraction force - mechanical anchorage loss; another from biologic force - physiologic anchorage loss. Since physiologic anchorage loss is caused by the continuous biologic force, the strategy of physiologic anchorage control (PAC is different from the strategy of mechanical anchorage control. A new PAC method is introduced in this article that can reduce the headgear and temporary anchorage device used as sagittal anchorage dramatically in orthodontic clinic.

  19. [Different orthodontic anchorage systems. A critical examination].

    Science.gov (United States)

    Diedrich, P

    1993-08-01

    Every orthodontic measure requires a detailed analysis of the individual anchorage situation in order to absorb (stationary anchorage) or control (reciprocal anchorage) the reactive forces and moments. Basically, an anchorage is oriented to the quality of the biological anchorage of the teeth. This is influenced by a number of factors: size of root surface, attachment level, density and structure of alveolar bone, periodontal reactivity, muscular activity, occlusal forces, craniofacial morphology and the nature of the tooth movement resulting from the planned correction. The quality of the biological anchorage may be enhanced by selective modification of the position of the anchor teeth: cortical anchorage of the first molar (Ricketts), distal inclination of the molars (Tweed, Begg) and differential torque control (Burstone). In this context, undesired anchorage effects also need to be discussed, for example interaction between the teeth being corrected and compact bone structures (symphysis menti, floor of the maxillary sinus) or the loss of anchorage by periodontal hyalinization or excessive friction within the bracket slot. In addition, the anchorage situation of ankylosed teeth and endosseous implants, as well as the advantages and disadvantages of additional mechanical anchorage aids (head-gear, Nance holding arch, lingual arch) are discussed. On the basis of the complexity of the individual biological and biomechanical aspects, guidelines are derived with which to establish anchorage control matched to the specific situation.

  20. 33 CFR 401.50 - Anchorage areas.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Anchorage areas. 401.50 Section... TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.50 Anchorage areas. Except in an... of the Seaway except in the following designated anchorage areas: (a) Point Fortier (Lake St....

  1. 77 FR 25587 - Anchorage Regulations; Wells, ME

    Science.gov (United States)

    2012-05-01

    ... SECURITY Coast Guard 33 CFR Part 110 RIN 1625-AA01 Anchorage Regulations; Wells, ME AGENCY: Coast Guard... three special anchorage areas in Wells Harbor, Wells, Maine, through a published final rule. The Marine.... Viewing Comments and Documents To view comments, as well as documents mentioned in this preamble as...

  2. 76 FR 52599 - Anchorage Regulations; Wells, ME

    Science.gov (United States)

    2011-08-23

    ... SECURITY Coast Guard 33 CFR Part 110 RIN 1625-AA01 Anchorage Regulations; Wells, ME AGENCY: Coast Guard... special anchorage areas in Wells Harbor, Wells, Maine. This proposed action is necessary to facilitate... in length. This action is intended to increase the safety of life and property in Wells...

  3. Paradigm shifts in orthodontic treatment with mini-implant anchorage

    Directory of Open Access Journals (Sweden)

    Johnny Joung-Lin Liaw

    2015-01-01

    Full Text Available After the applications of mini-implant anchorage, the envelope of orthodontic treatment was expanded and some treatment modes were changed because of more predictable tooth movement with empowered anchorage. The author tried to share his experience of TADs applications for clarifying the paradigm shifts of orthodontic treatment assisted with the mini-implant anchorage.

  4. 76 FR 76295 - Anchorage Regulations; Wells, ME

    Science.gov (United States)

    2011-12-07

    ... rule, call or email Mr. John J. Mauro, Waterways Management Branch Chief, First Coast Guard District; telephone (617) 223-8355, email John.J.Mauro@uscg.mil . If you have questions on viewing or submitting... placed well within the anchorage areas so that no portion of the hull or rigging will at any time...

  5. 77 FR 6010 - Anchorage Regulations; Newport, RI

    Science.gov (United States)

    2012-02-07

    ... of anchorage ``D'' at Newport, Rhode Island, to better accommodate increasing cruise ship visits to..., to better accommodate increasing cruise ship visits to Newport, and to improve navigation safety... ships simultaneously. Over the past several years, cruise ship visits to Newport, RI, have been...

  6. Comparison of temporary anchorage devices and transpalatal arch-mediated anchorage reinforcement during canine retraction

    Science.gov (United States)

    Kecik, Defne

    2016-01-01

    Objective: The purpose of this study was to compare the dental and skeletal effects of canine retraction using conventional anchorage reinforcement systems and comparing them with the usage of TADs. Materials and Methods: The sample consisted of 50 patients having Class I malocclusions with bimaxillary protrusion indicated for first premolar extraction, and allocated into two groups. The first group consisted of 25 patients with a mean age of 18,7 years (min:14, max:22 years, 16 girls and 9 boys) that TADs were applied as an anchorage mechanic between attached gingiva of upper second premolar and first molar teeth. The second group consisted of 25 patients with a mean age of 19,4 years (min:15, max:23 years, 14 girls and 11 boys) that conventional molar anchorage with Transpalatal arch (TPA) was applied for the anchorage mechanics against canine retraction. Results: The results showed that mean mesial movement and the tipping of the first molars in TAD group between T0 - T1 were insignificant (P > 0,05), however in the TPA group were significant (P0,05). Conclusion: Although TPA is a useful appliance, it doesn't provide an effective anchorage control on anteroposterior movement maxillary first molar teeth concerning first premolar extraction treatment. TADs are more convenient to provide absolute anchorage during maxillary canine retraction in contrast to transpalatal arch. PMID:28042267

  7. Orthodontic Anchorage Implants: State-of-the-art

    DEFF Research Database (Denmark)

    Melsen, Birte

    2007-01-01

    the optimal positioning of the teeth following rehabilitation. Patients with need for inconsistent tooth movements, borderline surgical cases, can benefit from the use of the mini-implant and regeneration of alveolar process by tooth movement in edentulous molar regions and using mini-implants as anchorage......The limits of an orthodontic treatment are often set by the lack of suitable anchorage. The mini-implant is used where conventional anchorage cannot be applied and not as a replacement for conventional anchorage. In patients with lack of teeth and reduced periodontium, skeletal anchorage allows...

  8. Procedures adopted by orthodontists for space closure and anchorage control

    Directory of Open Access Journals (Sweden)

    André da Costa Monini

    2013-12-01

    Full Text Available OBJECTIVE: The aim of this study was to identify the procedures adopted by Brazilian orthodontists in the following situations: extraction space closure, anchorage control in case of necessary anchorage for group A and frequency of skeletal anchorage use, especially in the upper jaw. METHOD: A questionnaire was sent to the e-mail address of all dentists registered in the Brazilian Federal Council of Dentistry. RESULTS: The results showed that most Brazilian orthodontists usually perform extraction space closure by means of sliding mechanics. The use of palatal bar, inclusion of second molars in the archwire and space closure performed in two phases are the most used techniques for anchorage control in the upper jaw. The skeletal anchorage is referenced by 36.5% of specialists as a routine practice for the upper jaw anchorage. CONCLUSIONS: There is a wide variety of procedures adopted by Brazilian orthodontists for orthodontic space closure and anchorage control.

  9. Is skeletal anchorage changing the limit of orthodontics?

    DEFF Research Database (Denmark)

    Melsen, Birte

    2007-01-01

    The limits for orthodontic treatment are often set by the lack of suitable anchorage. The mini-implant is used where conventional anchorage cannot be applied; not as a replacement for conventional anchorage. In patients with lack of teeth and reduced periodontium, skeletal anchorage allows...... for the optimal positioning of the teeth before rehabilitation. Patients, with need for inconsistent tooth movements as displacement of all teeth in the same direction or asymmetric displacements, can be treated with the mini-implants. Borderline surgical cases can benefit from the use of mini......-implants. Regeneration of the alveolar process by tooth movement in edentulous molar regions using mini-implants as anchorage will improve the possibilities for reconstruction. The mini-implant serves thus as anchorage for a multiplicity of tooth movements; it can be inserted by the orthodontist, requires no drilling...

  10. 76 FR 78185 - Anchorage Regulations: Subpart A-Special Anchorage Regulations, Newport Bay Harbor, CA

    Science.gov (United States)

    2011-12-16

    ....gov and will include any personal information you have provided. Submitting Comments If you submit a... would be incorporated into area A-11 under revised Sec. 110.95(k). An image of the proposed anchorage... rule under Executive Order 13045, Protection of Children from Environmental Health Risks and...

  11. Orthodontic treatment with skeletal anchorage system

    Directory of Open Access Journals (Sweden)

    Arya Brahmanta

    2011-06-01

    Full Text Available Background: Correction of class I malocclusion with bimaxillary dental protrusion and unilateral free end right upper ridge in adult patient is one of difficult biomechanical case in orthodontics. Due to this case that needs proper anchorage for upper incisor retraction with missing teeth in the right posterior segment. Purpose: The aim of this study to find an effective therapy for correction of bimaxillary protrusion with unilateral free and ridge. Case: A female patient, 36 year old complaining for the difficulty of lip closure due to severe bimaxillary protrusion with incompetence lip. Case management: Firstly correction of the maxillary and mandibular incisor proclination were done by extraction of the mandibular first premolar, the maxillary second premolar on left side and finally placement of miniplates implant in the zygomatic process on right side as an absolut anchorage. Conclusion: Skeletal anchorage system (SAS can be considered as an effective therapy for corection of bimaxillary protrusion with unilateral free end ridge.Latar belakang: Koreksi dari maloklusi klas I dari penderita dewasa yang disertai protrusi bimaksiler dengan kehilangan gigi posterior pada regio kanan atas merupakan salah satu kasus sulit untuk dikerjakan terutama berhubungan dengan biomekanik pergerakan giginya dalam perawatan ortodonti. Tujuan: Tujuan dari penulisan artikel ini adalah untuk menemukan terapi yang efektif untuk perbaikan protrusi bimaksiler dan kehilangan gigi posterior pada satu sisi. Kasus: Seorang penderita wanita usia 35 tahun datang dengan keluhan utama kesulitan untuk menutup mulut oleh karena gigi rahang atas dan rahang bawahnya maju dan bibirnya tidak kompeten. Tatalaksana kasus: Koreksi pada gigi insisivus rahang atas dan insisivus rahang bawah yang protrusi dilakukan dengan melakukan pencabutan terlebih dahulu pada gigi premolar pertama dirahang bawah sisi kanan dan sisi kiri serta pencabutan pada gigi premolar kedua di rahang atas sisi

  12. Shear and anchorage behaviour of fire exposed hollow core slabs

    NARCIS (Netherlands)

    Fellinger, J.H.H.; Stark, J.; Walraven, J.C.

    2005-01-01

    The fire resistance of hollow core slabs is currently assessed considering flexural failure only. However, fire tests showed that shear or anchorage failure can also govern the load bearing behaviour. As the shear and anchorage capacity of these slabs rely on the tensile strength of the concrete, th

  13. 77 FR 22489 - Special Anchorage Regulations, Newport Bay Harbor, CA

    Science.gov (United States)

    2012-04-16

    ... Master Plan Subcommittee of the City of Newport Harbor Commission led an outreach campaign involving a... meetings, the City of Newport asked the Coast Guard to amend its anchorage regulations. The Coast Guard... incorporated into area A-11 under revised Sec. 110.95(k). An image of the anchorage areas is available in...

  14. 77 FR 54493 - Special Anchorage Area; Stockton Springs, ME

    Science.gov (United States)

    2012-09-05

    ... Number USCG-2012-0172] RIN 1625-AA01 Special Anchorage Area; Stockton Springs, ME AGENCY: Coast Guard... anchorage area in Stockton Springs, Maine. This proposed action is necessary to facilitate safe navigation.... This action is intended to increase the safety of life and property in Stockton Springs, improve...

  15. Mechanical anchorage of FRP tendons – A literature review

    DEFF Research Database (Denmark)

    Schmidt, Jacob W.; Bennitz, Anders; Täljsten, Björn

    2012-01-01

    anchorage systems for use with Aramid, Glass and Carbon FRP tendons have been proposed over the last two decades. Each system is usually tailored to a particular type of tendon. This paper presents a brief overview of bonded anchorage applications while the primary literature review discusses three methods...

  16. Anchorage of Main Reinforcement in Lightweight Aggregate Concrete Beams

    DEFF Research Database (Denmark)

    Larsen, Henning

    1999-01-01

    The paper deals with the anchorage of reinforcement bars at end supports in beam component made of lightweight aggregate concrete with open structure.......The paper deals with the anchorage of reinforcement bars at end supports in beam component made of lightweight aggregate concrete with open structure....

  17. Deformation tests and failure process analysis of an anchorage structure

    Institute of Scientific and Technical Information of China (English)

    Zhao Tongbin; Yin Yanchun; Tan Yunliang; Song Yimin

    2015-01-01

    In order to study the failure process of an anchorage structure and the evolution law of the body’s defor-mation field, anchor push-out tests were carried out based on digital speckle correlation methods (DSCM). The stress distribution of the anchorage interface was investigated using the particle flow numerical simulation method. The results indicate that there are three stages in the deformation and fail-ure process of an anchorage structure:elastic bonding stage, a de-bonding stage and a failure stage. The stress distribution in the interface controls the stability of the structure. In the elastic bonding stage, the shear stress peak point of the interface is close to the loading end, and the displacement field gradually develops into a ‘V’ shape. In the de-bonding stage, there is a shear stress plateau in the center of the anchorage section, and shear strain localization begins to form in the deformation field. In the failure stage, the bonding of the interface fails rapidly and the shear stress peak point moves to the anchorage free end. The anchorage structure moves integrally along the macro-crack. The de-bonding stage is a research focus in the deformation and failure process of an anchorage structure, and plays an important guiding role in roadway support design and prediction of the stability of the surrounding rock.

  18. Minor tooth movements using microimplant anchorage: case reports.

    Science.gov (United States)

    Sohn, Dong-Seok; Lee, Jung-Kwang; An, Kyung-Mi

    2008-03-01

    For the treatment of extruded or tipped molars, various conventional techniques have been used. But those methods may lead to undesirable movement of the anchorage units and lengthen treatment time because of limited tooth-borne anchorage potential. Introduction of microimplants as orthodontic anchorage has expanded treatment possibilities because of their advantages. Some advantages are a less complex surgical procedure, decrease in cost, immediate loading, and their ability to be placed in any area of the alveolar bone. This article will illustrate clinical experiences in patients who were treated with the intrusion of overerupted molars, the up-righting of tilted molars, and other clinical applications for minor tooth movements. Anchorage control was achieved with the surgical insertion of titanium microimplants for immediate loading in the alveolar bone. When needed, minimal fixed appliances were used and orthodontic treatment was completed without any other complications.

  19. Urban contaminants project: Fish and Hood Creeks, Anchorage, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Urbanization has decreased water quality and adversely impacted biological communities in the lakes and streams of Anchorage, Alaska (Hock, 1981; Brabets, 1987;...

  20. 75 FR 3641 - Television Broadcasting Services; Anchorage, AK

    Science.gov (United States)

    2010-01-22

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 Television Broadcasting Services; Anchorage, AK AGENCY: Federal Communications... broadcasting. 0 For the reasons discussed in the preamble, the Federal Communications Commission amends 47...

  1. Railroad Bridges

    Data.gov (United States)

    Department of Homeland Security — Bridges-Rail in the United States According to The National Bridge Inspection Standards published in the Code of Federal Regulations (23 CFR 650.3), a bridge isA...

  2. Prevalence of the use of anchorage miniscrews among French orthodontists.

    Science.gov (United States)

    Barthelemi, Stéphane; Beauval, Hélène

    2015-12-01

    Since always, anchorage has raised frequent problems for orthodontists. Since the early 2000s, the use of anchorage miniscrews has spread on a vast scale among practitioners. For the first time, a broad epidemiological survey (733 exploitable responses) has looked into the habits of French orthodontists regarding the use of anchorage miniscrews. The survey reveals that the majority of French practitioners have adopted miniscrews in their daily practice (66%), particularly among those using the lingual technique. However, the number of patients concerned still remains small for most practitioners (fewer than 10 patients for 65% of users). Seventy-four percent of users are satisfied with their experience with miniscrews although a majority uses them exclusively in adults (64%). The movements most sought by miniscrew users are mesialization/distalization and intrusion/extrusion. Among non-users, 60% have never placed an anchorage miniscrew but are thinking about doing so, whereas 20% of practitioners have used them but have since abandoned them. Finally, 20% of non-users have never used anchorage miniscrews and do not intend to do so.

  3. Clinical applications of orthodontic microimplant anchorage in craniofacial patients.

    Science.gov (United States)

    Vachiramon, Amornpong; Urata, Mark; Kyung, Hee Moon; Yamashita, Dennis-Duke; Yen, Stephen L-K

    2009-03-01

    Microimplant anchors, also known as temporary anchorage devices, mini- and micro-screws, have been used to enhance orthodontic anchorage for difficult tooth movements. Here, the authors describe how microimplants can be used to help treat craniofacial patients by supporting distraction osteogenesis procedures, maxillary protraction procedures, cleft segment expansion and stabilization, and tooth movement into narrow alveolar cleft sites. While most craniofacial patients are treated without microimplants, it would be worthwhile to identify which cases could benefit from microimplant anchorage. As an adjunct to orthodontic treatment, the microimplant offers a potential method for solving troublesome orthodontic and surgical problems such as guiding distraction procedures with orthodontics when primary teeth are exfoliating, addressing residual maxillary cants after vertical distraction osteogenesis of a ramus, stabilizing an edentulous premaxilla, and moving teeth into atrophic alveolar ridges. These cases are presented to open a dialogue on their possible uses in craniofacial patients.

  4. Shear and anchorage behaviour of fire exposed hollow core slabs

    NARCIS (Netherlands)

    Fellinger, J.

    2005-01-01

    The fire resistance of hollow core slabs is currently assessed considering flexural failure only. However, fire tests show that shear or anchorage failure can also govern the load bearing behaviour. This paper is based on the dissertation by the author1 and discusses existing and new fire tests. It

  5. Shear and Anchorage Behaviour of Fire Exposed Hollow Core Slabs

    NARCIS (Netherlands)

    Fellinger, J.H.H.

    2004-01-01

    Hollow core (HC) slabs are made of precast concrete with pretensioned strands. These slabs are popular as floor structures in offices and housing. At ambient conditions, the load bearing capacity can be dominated by four different failure modes, i.e. flexure, anchorage, shear compression and shear t

  6. Oral and dental restoration of wide alveolar cleft using distraction osteogenesis and temporary anchorage devices.

    Science.gov (United States)

    Rachmiel, Adi; Emodi, Omri; Gutmacher, Zvi; Blumenfeld, Israel; Aizenbud, Dror

    2013-12-01

    Closure of large alveolar clefts and restoration by a fixed bridge supported by implants is a challenge in cleft alveolus treatment. A major aesthetic concern with distraction osteogenesis is obtaining a predictable position of the implant in relation to the newly generated bony alveolar ridge. We describe the treatment of a large cleft alveolus and palate reconstruction by distraction osteogenesis utilizing temporary anchorage devices (TADs) followed by a fixed implant-supported bridge. The method consists of segmental bone transport by distraction osteogenesis using a bone-borne distractor to minimize the alveolar cleft, followed by closure of the residual small defect by bone grafting three months later. During the active transport distraction, TADs were used exerting multidirectional forces to control the distraction vector forward and laterally for better interarch relation. A vertical alveolar distraction of the newly reconstructed bone of 15 mm facilitated optimal implant placement. The endosseous implants were osteointegrated and supported a fixed dental prosthesis. In conclusion, the large cleft alveolus defect was repaired in three dimensions by distraction osteogenesis assisted by TADs, and the soft tissues expanded simultaneously. Endosseous implants were introduced in the newly reconstructed bone for a fixed dental prosthesis enabling, rehabilitation of aesthetics, eating and speaking.

  7. Uvulo-glossopharyngeal dimensions in non-extraction, extraction with minimum anchorage, and extraction with maximum anchorage.

    Science.gov (United States)

    Germec-Cakan, Derya; Taner, Tulin; Akan, Seden

    2011-10-01

    The aim of this study was to investigate upper respiratory airway dimensions in non-extraction and extraction subjects treated with minimum or maximum anchorage. Lateral cephalograms of 39 Class I subjects were divided into three groups (each containing 11 females and 2 males) according to treatment procedure: group 1, 13 patients treated with extraction of four premolars and minimum anchorage; group 2, 13 cases treated non-extraction with air-rotor stripping (ARS); and group 3, 13 bimaxillary protrusion subjects treated with extraction of four premolars and maximum anchorage. The mean ages of the patients were 18.1 ± 3.7, 17.8 ± 2.4, and 15.5 ± 0.88 years, respectively. Tongue, soft palate, hyoid position, and upper airway measurements were made on pre- and post-treatment lateral cephalograms and the differences between the mean measurements were tested using Wilcoxon signed-ranks test. Superior and middle airway space increased significantly (P extraction treatment using maximum anchorage has a reducing effect on the middle and inferior airway dimensions.

  8. Reductive carboxylation supports redox homeostasis during anchorage-independent growth.

    Science.gov (United States)

    Jiang, Lei; Shestov, Alexander A; Swain, Pamela; Yang, Chendong; Parker, Seth J; Wang, Qiong A; Terada, Lance S; Adams, Nicholas D; McCabe, Michael T; Pietrak, Beth; Schmidt, Stan; Metallo, Christian M; Dranka, Brian P; Schwartz, Benjamin; DeBerardinis, Ralph J

    2016-04-14

    Cells receive growth and survival stimuli through their attachment to an extracellular matrix (ECM). Overcoming the addiction to ECM-induced signals is required for anchorage-independent growth, a property of most malignant cells. Detachment from ECM is associated with enhanced production of reactive oxygen species (ROS) owing to altered glucose metabolism. Here we identify an unconventional pathway that supports redox homeostasis and growth during adaptation to anchorage independence. We observed that detachment from monolayer culture and growth as anchorage-independent tumour spheroids was accompanied by changes in both glucose and glutamine metabolism. Specifically, oxidation of both nutrients was suppressed in spheroids, whereas reductive formation of citrate from glutamine was enhanced. Reductive glutamine metabolism was highly dependent on cytosolic isocitrate dehydrogenase-1 (IDH1), because the activity was suppressed in cells homozygous null for IDH1 or treated with an IDH1 inhibitor. This activity occurred in absence of hypoxia, a well-known inducer of reductive metabolism. Rather, IDH1 mitigated mitochondrial ROS in spheroids, and suppressing IDH1 reduced spheroid growth through a mechanism requiring mitochondrial ROS. Isotope tracing revealed that in spheroids, isocitrate/citrate produced reductively in the cytosol could enter the mitochondria and participate in oxidative metabolism, including oxidation by IDH2. This generates NADPH in the mitochondria, enabling cells to mitigate mitochondrial ROS and maximize growth. Neither IDH1 nor IDH2 was necessary for monolayer growth, but deleting either one enhanced mitochondrial ROS and reduced spheroid size, as did deletion of the mitochondrial citrate transporter protein. Together, the data indicate that adaptation to anchorage independence requires a fundamental change in citrate metabolism, initiated by IDH1-dependent reductive carboxylation and culminating in suppression of mitochondrial ROS.

  9. Synergetic material and structure optimization yields robust spider web anchorages.

    Science.gov (United States)

    Pugno, Nicola M; Cranford, Steven W; Buehler, Markus J

    2013-08-26

    Millions of years of evolution have adapted spider webs to achieve a range of properties, including the well-known capture of prey, with efficient use of materials. One feature that remains poorly understood is the attachment disc, a network of silk fibers that mechanically anchors a web to its environment. Experimental observations suggest that one possible attachment disc adheres to a substrate through multiple symmetrically branched structures composed of sub-micrometer scale silk fibers. Here, a theoretical model is used to explore the adaptation of the strength of attachment of such an anchorage, and complementary mesoscale simulations are applied to demonstrate a novel mechanism of synergetic material and structural optimization, such that the maximum anchorage strength can be achieved regardless of the initial anchor placement or material type. The optimal delamination (peeling) angle is facilitated by the inherent extensibility of silk, and is attained automatically during the process of delamination. This concept of self-optimizing peeling angle suggests that attachment discs do not require precise placement by the spider, irrespective of adhesion strength. Additional hierarchical branching of the anchorage increases efficiency, where both the delamination force and toughness modulus increase with a splitting of the cross-sectional area.

  10. Image guided placement of temporary anchorage devices for tooth movement

    Energy Technology Data Exchange (ETDEWEB)

    Bahl-Palomo, L.; Bissada, N. [Case Western Reserve Univ. School of Dental Medicine, Dept. of Periodontics, Cleveland, OH (United States); Palomo, J.M.; Hans, M.G. [Case Western Reserve Univ. School of Dental Medicine, Dept. of Orthodontics, Cleveland, OH (United States)

    2007-06-15

    The aim of this project is to develop an image guided protocol for placement of a temporary anchorage device without surgically reflecting a mucoperiosteal flap. Eighteen orthodontic cases were selected for skeletal anchorage from the department of orthodontics at Case University. CBCT images of the subjects were taken using the Hitachi CB MercuRay system set at 15 mA, 120 kVp. CBCT images evaluated the ideal location for TAD placement in three dimensions. Horizontal and vertical linear measurements were taken from fixed dental landmarks to clearly define the location for placement. Transverse slices were used to evaluate the thickness of the buccal plate. Using the transverse view, the angle of insertion was determined such that the maximum buccal plate surface area would contact the screw. TADs were placed in the optimum location, with the most appropriate angle of insertion using a closed approach and with minimal local anesthesia and without flap elevation. Results: All TADs were placed without anatomic encroachment and enabled fixed orthodontic anchorage. (orig.)

  11. Application study on the first cable-stayed bridge with CFRP cables in China

    Directory of Open Access Journals (Sweden)

    Kuihua Mei

    2015-08-01

    Full Text Available In order to push forward the development of CFRP cable-stayed bridge and accumulate experiences, the study on the application of the first cable-stayed bridge with CFRP cables in China was carried out. The design essentials of main components of the bridge were introduced and its integral performances, including static properties, dynamic properties and seismic response were analyzed using finite element method. A new bond-type anchorage was developed and the processes of fabricating and installing CFRP cables were elaborated. Based on the results of construction simulation, a tension scheme for bridge was propound. During constructing, the stresses and displacement of girder and pylon, as well as the forces and stresses of cables, were tested. The results indicate that all sections of the bridge could meet the requirements of the ultimate bearing capacity and normal service; the performance of the anchorage is good and the stresses in each cable system are similar; the tested values accord well with the calculated values. Further, creep deformation of the resin in anchorages under service load is not obvious. All these results demonstrate that the first application of CFRP cables in the cable-stayed bridge in China is successful.

  12. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  13. External post-tensioning of cfrp tendons using integrated sleeve-wedge anchorage

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Bennitz, Anders; Goltermann, Per

    2012-01-01

    Strengthening of structures using external post-tension CFRP systems have proven to be anefficient method as such system increases the structural capacity and reduces cracks and deflection. Sufficient anchorage is of significant importance since the anchorage provides the connection between...... the post-tensioning system and the remaining structure. A special designed integrated sleeve-wedge anchorage has therefore been designed to improve the reliability of the mounting procedure, reduce the possible modes of failure and thus provide desired anchorage. The present research shows that adequate...

  14. Finite element simulation and testing of ISW CFRP anchorage

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Goltermann, Per; Hertz, Kristian Dahl

    2013-01-01

    Several Carbon Fibre Reinforced Polymers (CFRP) systems have been used successfully for strengthening of structures during the last decades. However, the fracture often occurs in the concrete adherent or in the adhesive interface when used for steel strengthening. As a consequence the CFRP...... is poorly utilized with a non ductile and brittle failure mode as the outcome. Mechanical anchorage can be used to utilize the full capacity of the CFRP materials but cannot yet challenge systems used for steel. Such systems can be used to transfer stresses from the CFRP material efficiently...

  15. Managing complex orthodontic problems: the use of implants for anchorage.

    Science.gov (United States)

    Kokich, V G

    1996-06-01

    Today implants are commonly used to replace missing teeth in partially edentulous adult orthodontic patients. Because these patients are missing teeth, orthodontic mechanics may be complicated or often impossible because of insufficient anchorage. In these situations, it may be feasible to use the implant initially as an orthodontic anchor to facilitate complex tooth movement and secondarily as an abutment for a crown or fixed prosthesis. This article will discuss the ramifications and requirements for using implants as anchors and abutments in adult orthodontic patients.

  16. Comparative photoelastic study of dental and skeletal anchorages in the canine retraction

    Directory of Open Access Journals (Sweden)

    Cristiane Aparecida de Assis Claro

    2014-01-01

    Full Text Available OBJECTIVE: To compare dental and skeletal anchorages in mandibular canine retraction by means of a stress distribution analysis. METHODS: A photoelastic model was produced from second molar to canine, without the first premolar, and mandibular canine retraction was simulated by a rubber band tied to two types of anchorage: dental anchorage, in the first molar attached to adjacent teeth, and skeletal anchorage with a hook simulating the mini-implant. The forces were applied 10 times and observed in a circular polariscope. The stresses located in the mandibular canine were recorded in 7 regions. The Mann-Whitney test was employed to compare the stress in each region and between both anchorage systems. The stresses in the mandibular canine periradicular regions were compared by the Kruskal-Wallis test. RESULTS: Stresses were similar in the cervical region and the middle third. In the apical third, the stresses associated with skeletal anchorage were higher than the stresses associated with dental anchorage. The results of the Kruskal-Wallis test showed that the highest stresses were identified in the cervical-distal, apical-distal, and apex regions with the use of dental anchorage, and in the apical-distal, apical-mesial, cervical-distal, and apex regions with the use of skeletal anchorage. CONCLUSIONS: The use of skeletal anchorage in canine retraction caused greater stress in the apical third than the use of dental anchorage, which indicates an intrusive component resulting from the direction of the force due to the position of the mini-implant and the bracket hook of the canine.

  17. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

  18. 78 FR 9811 - Anchorages; Captain of the Port Puget Sound Zone, WA

    Science.gov (United States)

    2013-02-12

    ... area with a radius of 600 yards, having its center at 48 31'09'' N, 122 34'55'' W. (11) Cap Sante Tug and Barge General Anchorage. The Cap Sante Tug and Barge General Anchorage includes all waters... northeast tip of Cap Sante; then southeast to 48 30'53'' N, 122 35'28'' W; then west southwest to 48...

  19. 33 CFR 110.189a - Key West Harbor, Key West, Fla., naval explosives anchorage area.

    Science.gov (United States)

    2010-07-01

    ..., Key West, Fla., naval explosives anchorage area. (a) The anchorage ground. A circular area with its center at latitude 24°30′50.6″, longitude 81°50′31.6″ with a radius of 300 yards, for use for ammunition exceeding the prescribed limits for pier-side handling. (b) The regulations. (1) When occupied by a...

  20. Flexural Strengthening of RC Slabs with Prestressed CFRP Strips Using Different Anchorage Systems

    Directory of Open Access Journals (Sweden)

    José Sena-Cruz

    2015-10-01

    Full Text Available Externally Bonded Reinforcement (EBR technique has been widely used for flexural strengthening of concrete structures by using carbon fiber-reinforced polymers (CFRP. EBR technique offers several structural advantages when the CFRP material is prestressed. This paper presents an experimental and numerical study on reinforced (RC slabs strengthened in flexure with prestressed CFRP strips as a structural strengthening system. The strips are applied as an externally bonded reinforcement (EBR and anchored with either a mechanical or a gradient anchorage. The former foresees metallic anchorage plates fixed to the concrete substrate, while the latter is based on an accelerated epoxy resin curing followed by a segment-wise prestress force decrease at the strip ends. Both anchorage systems, in combination with different CFRP strip geometries, were subjected to static loading tests. It could be demonstrated that the composite strip’s performance is better exploited when prestressing is used, with slightly higher overall load carrying capacities for mechanical anchorages than for the gradient anchorage. The performed investigations by means of a cross-section analysis supported the experimental observation that in case a mechanical anchorage is used, progressive strip debonding changes the fully bonded configuration to an unbonded end-anchored system. The inclusion of defined debonding criteria for both the anchorage zones and free length between the anchorage regions allowed to precisely capture the ultimate loading forces.

  1. 49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Seats, seat belt assemblies, and seat belt... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses... the driver's seat and seat belt assembly anchorages that conform to the location and...

  2. Summary of Quaternary geology of the Municipality of Anchorage, Alaska

    Science.gov (United States)

    Schmoll, H.R.; Yehle, L.A.; Updike, R.G.

    1999-01-01

    Quaternary geology of the Upper Cook Inlet region is dominated by deposits of glacier retreats that followed repeated advances from both adjacent and more distant mountains. At several levels high on the mountains, there are remnant glacial deposits and other features of middle or older Pleistocene age. Late Pleistocene lateral moraines along the Chugach Mountain front represent successively younger positions of ice retreat from the last glacial maximum. As the trunk glacier retreated northeastward up the Anchorage lowland, Cook Inlet transgressed the area, depositing the Bootlegger Cove Formation and Tudor Road deposits. The glacier then readvanced to form the latest Pleistocene Elmendorf Moraine, a prominent feature that trends across the Anchorage lowland. Extensive alluvium was deposited both concurrently and somewhat later as Cook Inlet regressed. Mountain valleys contain (1) locally preserved moraines possibly of early Holocene age; (2) poorly preserved moraine remnants of older late Holocene age; and (3) well-preserved moraines formed mainly during the Little Ice Age. Glaciers still occupy large parts of the mountains, the upper ends of some mountain valleys, and small cirques. Holocene landslide deposits, including those formed during the great Alaska earthquake of 1964, occur throughout the area, especially along bluffs containing the Bootlegger Cove Formation.

  3. Treatment of a Class II deepbite with microimplant anchorage.

    Science.gov (United States)

    Park, Hyo-Sang; Kim, Ji-Yeun; Kwon, Tae-Geon

    2011-03-01

    The goal of this report was to illustrate new treatment mechanics for using microimplants for the treatment of a Class II Division 2 deepbite malocclusion. A 29-year-old woman with a deepbite was treated with the aid of microimplant anchorage. Microimplants placed between the maxillary second premolars and first molars were used as anchorage to apply a distal force to the anterior teeth to correct the Class II canine and molar relationships. A distal force was applied to long hooks that were crimped between the lateral incisors and the canines. By applying a backward force to the long hooks, the maxillary anterior teeth experienced palatal root movement with no change in the vertical and anteroposterior positions of the incisal edges. The distal extrusive movement of the maxillary second molars achieved by disengaging the second molars from the archwire during distal force application and an anterior bite-block bonded on the lingual surface of the maxillary central incisors produced the increase in vertical dimension. The distal force to the long extended hooks from the microimplants was possibly good mechanics for obtaining the palatal root movement and correcting the Class II canine and molar relationships. The anterior bite-block and disengagement of the maxillary second molars during distal force application were effective for increasing the vertical dimension.

  4. Mini-Implants in the Anchorage Armamentarium: New Paradigms in the Orthodontics

    Science.gov (United States)

    Yamaguchi, Masaru; Inami, Toshihiro; Ito, Ko; Kasai, Kazutaka; Tanimoto, Yasuhiro

    2012-01-01

    Paradigms have started to shift in the orthodontic world since the introduction of mini-implants in the anchorage armamentarium. Various forms of skeletal anchorage, including miniscrews and miniplates, have been reported in the literature. Recently, great emphasis has been placed on the miniscrew type of temporary anchorage device (TAD). These devices are small, are implanted with a relatively simple surgical procedure, and increase the potential for better orthodontic results. Therefore, miniscrews not only free orthodontists from anchorage-demanding cases, but they also enable clinicians to have good control over tooth movement in 3 dimensions. The miniplate type also produces significant improvements in treatment outcomes and has widened the spectrum of orthodontics. The purpose of this paper is to update clinicians on the current concepts and versatile uses and clinical applications of skeletal anchorage in orthodontics. PMID:22719763

  5. Evaluation of dredged material proposed for ocean disposal from Gravesend Bay Anchorage, New York

    Energy Technology Data Exchange (ETDEWEB)

    Barrows, E.S.; Gruendell, B.D. [Battelle/Marine Sciences Lab., Sequim, WA (United States)

    1996-09-01

    The Gravesend Bay Anchorage was one of seven waterways that the US Army Corps of Engineers-New York District (USACE-NYD) requested the Battelle Marine Sciences Laboratory (MSL) to sample and evaluate for dredging and disposal in February 1994. Sediment samples were submitted for physical and chemical analyses to provide baseline sediment chemistry data on the Gravesend Bay Anchorage. Individual sediment core samples collected at the Gravesend Bay Anchorage were analyzed for grain size, moisture content, and total organic carbon (TOC). Two samples, one of composited sediment cores representing the southeast corner of the anchorage (COMP GR), and one sediment core representing the northeast corner of the anchorage (Station GR-1 0), were analyzed for bulk density, specific gravity, metals, chlorinated pesticides, polychlorinated biphenyl (PCB) congeners, polynuclear aromatic hydrocarbons (PAH), and 1,4-dichlorobenzene.

  6. Mini-Implants in the Anchorage Armamentarium: New Paradigms in the Orthodontics

    Directory of Open Access Journals (Sweden)

    Masaru Yamaguchi

    2012-01-01

    Full Text Available Paradigms have started to shift in the orthodontic world since the introduction of mini-implants in the anchorage armamentarium. Various forms of skeletal anchorage, including miniscrews and miniplates, have been reported in the literature. Recently, great emphasis has been placed on the miniscrew type of temporary anchorage device (TAD. These devices are small, are implanted with a relatively simple surgical procedure, and increase the potential for better orthodontic results. Therefore, miniscrews not only free orthodontists from anchorage-demanding cases, but they also enable clinicians to have good control over tooth movement in 3 dimensions. The miniplate type also produces significant improvements in treatment outcomes and has widened the spectrum of orthodontics. The purpose of this paper is to update clinicians on the current concepts and versatile uses and clinical applications of skeletal anchorage in orthodontics.

  7. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

    Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

  8. Design of Main Bridge of Guizhou Wujiang River Bridge%贵州乌江大桥主桥设计

    Institute of Scientific and Technical Information of China (English)

    张伟; 曹洪武; 易伦雄

    2013-01-01

    The main bridge of Guizhou Wujiang River Bridge is a 325 m single-span suspension bridge of simply-supported concrete slab stiffening girder. The cross section of the stiffening girder is the dumbbell section, the towers are the portal frame structures of rectangular solid sections and are supported on the dug pile foundations. The anchorage of the bridge on the Xifeng bank is the gravity anchorage while on the Jinsha bank is the tunnel-type anchorage. The main cables consist of the ψ5. 1 mm high-strength galvanized steel wires and the suspenders are made up of the #3. 0 mm low-relaxation and high-strength galvanized parallel steel wires. The software MIDAS Civil 2006 was used to analyze the spatial global force conditions of the bridge and the software FLAC3D was used as well to carry out the three-dimensional elastoplastic numerical calculation and analysis of the tunnel-type anchorage and its surrounding rock. The results of the analysis showed that the various checking calculations of the bridge could meet the relevant requirements in the codes.%贵州乌江大桥主桥为325m单跨简支混凝土板式加劲梁悬索桥.该桥加劲梁采用哑铃形截面;桥塔采用门形框架结构,矩形实心截面,采用挖孔灌注桩基础;息烽岸采用重力锚碇,金沙岸采用隧道锚碇;主缆采用φ5.1 mm镀锌高强钢丝,吊索采用φ5.0 mm低松弛镀锌高强平行钢丝.采用MIDAS Civil 2006软件对该桥进行空间整体受力分析,并采用FLAC3D软件对隧道锚及围岩进行三维弹塑性数值计算分析,结果表明该桥各项检算均满足规范要求.

  9. 1964 Great Alaska Earthquake: a photographic tour of Anchorage, Alaska

    Science.gov (United States)

    Thoms, Evan E.; Haeussler, Peter J.; Anderson, Rebecca D.; McGimsey, Robert G.

    2014-01-01

    On March 27, 1964, at 5:36 p.m., a magnitude 9.2 earthquake, the largest recorded earthquake in U.S. history, struck southcentral Alaska (fig. 1). The Great Alaska Earthquake (also known as the Good Friday Earthquake) occurred at a pivotal time in the history of earth science, and helped lead to the acceptance of plate tectonic theory (Cox, 1973; Brocher and others, 2014). All large subduction zone earthquakes are understood through insights learned from the 1964 event, and observations and interpretations of the earthquake have influenced the design of infrastructure and seismic monitoring systems now in place. The earthquake caused extensive damage across the State, and triggered local tsunamis that devastated the Alaskan towns of Whittier, Valdez, and Seward. In Anchorage, the main cause of damage was ground shaking, which lasted approximately 4.5 minutes. Many buildings could not withstand this motion and were damaged or collapsed even though their foundations remained intact. More significantly, ground shaking triggered a number of landslides along coastal and drainage valley bluffs underlain by the Bootlegger Cove Formation, a composite of facies containing variably mixed gravel, sand, silt, and clay which were deposited over much of upper Cook Inlet during the Late Pleistocene (Ulery and others, 1983). Cyclic (or strain) softening of the more sensitive clay facies caused overlying blocks of soil to slide sideways along surfaces dipping by only a few degrees. This guide is the document version of an interactive web map that was created as part of the commemoration events for the 50th anniversary of the 1964 Great Alaska Earthquake. It is accessible at the U.S. Geological Survey (USGS) Alaska Science Center website: http://alaska.usgs.gov/announcements/news/1964Earthquake/. The website features a map display with suggested tour stops in Anchorage, historical photographs taken shortly after the earthquake, repeat photography of selected sites, scanned documents

  10. FRP tendon anchorage in post-tensioned concrete structures

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Täljsten, Björn; Bennitz, Anders

    2008-01-01

    Strengthening of building structures by the use of various external post-tensioning steel tendon systems, is known to be a very efficient method. However, FRP as material in external post-tensioning projects has been investigated during the last decade. The advantages for this material are the high...... transfer points. The demand for high capacity anchorage tendons is fulfilled for steel tendons, but no competitive mechanical anchor has yet been developed for FRP tendon. A new small, reliable and more user friendly anchor has to be developed, before FRP tendons can be utilized with all of its capacity....... Thus, several attempts of developing a mechanical FRP anchor have been made worldwide with promising results. Some of these attempts are presented in this paper together with an insight into a present research collaboration project at the Technical University of Denmark, Luleå University of Technology...

  11. Numerical Analysis of Quality Inspection of Anchorage System

    Institute of Scientific and Technical Information of China (English)

    ZHANGYongxing; XUMing

    2002-01-01

    Sonoprobe method has been applied in non-destructive inspection of anchorage project.The fundament is that dynamic transient excitation causes the elastic vibration of an anchor bar,and flaws can be estimated or deduced by determining transient response of the anchor bar.FEA numeric solution of hyperbolic equation indicates that deductions must comply with acoustic parameters such as velocity of sound,vibration range,wave shape etc when inspecting interior flaws in the grout of an anchor bar,Based on wavelet packet analysis,the energy eigenvector is a flaw vector,which could be regarded as the basis in the nondestructive inspection of anchors,As a non-linear dynamical system,artifical neural networks dealing with quality insection of gray system have been proved efficient.

  12. Comparison of Anchorage Pattern under Two Types of Orthodontic Mini- Implant Loading During Retraction in Type A Anchorage Cases

    Science.gov (United States)

    Khan, B. Imran; Mandava, Prasad; Reddy, G. Vivek; Nettam, Venkatesh; Bhavikati, Venkat Naidu

    2016-01-01

    Introduction The orthodontic mini-screws are the mainstay of direct skeletal anchorage which requires minimal compliance and provides maximal anchorage control. However, the timing of initiation of orthodontic loading of these mini-screws is not clearly established in the available studies. Aim The purpose of this study was to determine the reciprocal effects on mini-screw implant with immediate loading in comparison to that of delayed loading during retraction. Materials and Methods The prospective clinical study included a sample of 25 orthodontic patients in the age range of 18-25 years. All the cases were of bi-maxillary proclination with Type-A anchorage demands. All the first premolars were indicated for extraction. A split mouth technique for each patient was utilized by loading mini-implant immediately after its placement on one side and the opposite side implant was loaded after a time lag of two weeks post-insertion. Retraction force of 150g was applied for three months on each side. The displacement of the head and tail of the implant, molar anterior tooth retraction was measured on Orthopantomograph (OPG) taken at T1 (initial) and T2 (after three months). A grid method with each 1mm magnified to 500 pixels was superimposed on OPG and the relative displacements were evaluated. Student’s unpaired ‘t’ test was used for comparison between left and right side and paired ‘t’ test for the parameters on the same side. The p-value equal to or less than 0.05 was taken as statistically significant. Results The mean displacement of head of the implant on the immediate loading is 0.57mm where as the tail exhibited 0.75 mm. The head and tail of the implant on the delayed loading displaced by 0.35mm and 0.38mm respectively, on an average when data was analysed. Significant difference between the two types of loading was noted. Conclusion Delayed loading is beneficial as compared to immediate loading during extraction space closure. PMID:27891469

  13. Exterior beam-column joint study with non-conventional reinforcement detailing using mechanical anchorage under reversal loading

    Indian Academy of Sciences (India)

    S Rajagopal; S Prabavathy

    2014-10-01

    Reinforced concrete structures beam-column joints are the most critical regions in seismic prone areas. Proper reinforcement anchorage is essential to enhance the performance of the joints. An attempt has been made to appraise the performance of the anchorages and joints. The anchorages are detailed as per ACI-352 (mechanical anchorages), ACI-318 (conventional bent hooks) and IS-456 (conventional full anchorage). The joints are detailed without confinement in group-I and with additional X-cross bar in group-II. To assess the seismic performance, the specimens are assembled into two groups of three specimens each and were tested under reversal loading, The specimen with T-type mechanical anchorage (Headed bar) and T-type mechanical anchorage combination with X-cross bar exhibited significant improvement in seismic performance: load-displacement capacity, displacement ductility, stiffness degradation, controlled crack capacity in the joint shear panel and also reduced congestion of reinforcement in joint core.

  14. Numerical Simulation and Experimental Validation of an Integrated Sleeve-Wedge Anchorage for CFRP Rods

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Smith, Scott T.; Täljsten, Björn;

    2011-01-01

    . Recently, an integrated sleeve-wedge anchorage has been successfully developed specifically for CFRP rods. This paper in turn presents a numerical simulation of the newly developed anchorage using ABAQUS. The three-dimensional finite element (FE) model, which considers material non-linearity, uses...... hexagonal elements for the barrel and CFRP rod and tetrahedral elements for the integrated sleeve-wedge. The simulated barrel surface strains are shown to compare well with optically measured strains, however, the numerical results are shown to be sensitive to the mechanical properties of the anchorage...

  15. Bridged graphite oxide materials

    Science.gov (United States)

    Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

    2010-01-01

    Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

  16. Urban contaminants project: Data for sediment, fish and eggs collected from Chester Creek, Anchorage, Alaska 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Urbanization has degraded the water quality and adversely impacted biological communities in the lakes and streams of Anchorage. Pollution from point and nonpoint...

  17. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience...... Belgrade), Leo Pekkala (Finnish Centre for Media Education and Audiovisual Media/MEKU), Julie Uldam (Network on Civic Engagement and Social Innovation) and Gabriella Velics (Community Media Forum Europe)....

  18. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  19. Plastic Bridge

    Institute of Scientific and Technical Information of China (English)

    履之

    1994-01-01

    Already ubiquitous in homes and cars, plastic is now appearing inbridges. An academic-industrial consortium based at the University ofCalifornia in San Diego is launching a three-year research program aimed atdeveloping the world’s first plastic highway bridge, a 450-foot span madeentirely from glass-,carbon,and polymer-fiber-reinforced composite mate-rials, the stuff of military aircraft. It will cross Interstate 5 to connect thetwo sides of the school’s campus.

  20. Transfer and anchorage bond behaviour in self-compacting concrete

    Directory of Open Access Journals (Sweden)

    Rigueira-Víctor, J. W.

    2006-12-01

    Full Text Available Self-compacting concretes (SCC provide solutions to the problems facing precast concrete construction, enhancing competitiveness, reducing turnaround times and improving final product quality. SCC is fast becoming a key product for the future development of the precast pre-stressed concrete industry.The present paper compares the bond performance of SCC and traditional concrete (TC. The bond performance results confirm the viability of SCC in precast pre-stressed concrete manufacture, despite a slightly higher loss of pre-stressing force and slightly greater anchorage lengths in SCC with a low water/cement ratio. No differences in transfer or anchorage length were detected,however, when high strength TC and SCC were compared. The ECADA test method proved to be well suited to detecting the differences between the concretes analyzed.El desarrollo de los hormigones autocompactantes (SCCofrece muchas posibilidades a las construcciones con hormigón prefabricado, aumentando su competitividad, reduciéndolos plazos de fabricación y ofreciendo mejoras en la calidad del producto final. El SCC se está convirtiendo en un producto clave para el futuro desarrollo de la industria de prefabricados de hormigón pretensado.En este estudio se compara el comportamiento adherente de los SCC con el de los hormigones tradicionales (TC actuales. Los resultados obtenidos confirman la viabilidad del uso de los SCC para la fabricación de elementos prefabricados con hormigón pretensado, en lo relativo a su comportamiento adherente, aunque con la necesidad de considerar unas pérdidas de pretensado ligeramente mayores. Asimismo,debe esperarse un ligero aumento de las longitudes de anclaje cuando se trabaje con SCC de baja relación agua/cemento. Sin embargo, no se han detectado diferencias de comportamiento entre ambos tipos de hormigón cuando la resistencia a compresión es alta en lo relativo a las longitudes de transmisión y anclaje. El método de ensayo ECADA

  1. Mechanical properties and failure characteristics of fractured sandstone with grouting and anchorage

    Institute of Scientific and Technical Information of China (English)

    Zong Yijiang; Han Lijun; Qu Tao; Yang Shengqi

    2014-01-01

    Based on uniaxial compression experimental results on fractured sandstone with grouting and anchorage, we studied the strength and deformation properties, the failure model, crack formation and evolution laws of fractured sandstone under different conditions of anchorage. The experimental results show that the strength and elastic modulus of fractured sandstone with different fracture angles are sig-nificantly lower than those of intact sandstone. Compared with the fractured samples without anchorage, the peak strength, residual strength, peak and ultimate axial strain of fractured sandstone under different anchorage increase by 64.5-320.0%, 62.8-493.0%, and 31.6-181.4%, respectively. The number of bolts and degree of pre-stress has certain effects on the peak strength and failure model of fractured sandstone. The peak strength of fractured sandstone under different anchorage increases to some extent, and the failure model of fractured sandstone also transforms from tensile failure to tensile-shear mixed failure with the number of bolts. The pre-stress can restrain the formation and evolution process of tensile cracks, delay the failure process of fractured sandstone under anchorage and impel the transformation of failure model from brittle failure to plastic failure.

  2. Maps showing seismic landslide hazards in Anchorage, Alaska

    Science.gov (United States)

    Jibson, Randall W.

    2014-01-01

    The devastating landslides that accompanied the great 1964 Alaska earthquake showed that seismically triggered landslides are one of the greatest geologic hazards in Anchorage. Maps quantifying seismic landslide hazards are therefore important for planning, zoning, and emergency-response preparation. The accompanying maps portray seismic landslide hazards for the following conditions: (1) deep, translational landslides, which occur only during great subduction-zone earthquakes that have return periods of =300-900 yr; (2) shallow landslides for a peak ground acceleration (PGA) of 0.69 g, which has a return period of 2,475 yr, or a 2 percent probability of exceedance in 50 yr; and (3) shallow landslides for a PGA of 0.43 g, which has a return period of 475 yr, or a 10 percent probability of exceedance in 50 yr. Deep, translational landslide hazards were delineated based on previous studies of such landslides, with some modifications based on field observations of locations of deep landslides. Shallow-landslide hazards were delineated using a Newmark-type displacement analysis for the two probabilistic ground motions modeled.

  3. Construction of stiffening girder for Akashi straits bridge. Installation with use of latest bridging technology; Akashi kaikyo ohashi hoko keta kasetsu koji. Saishin kakyo gijutsu wo kushishite kasetsu

    Energy Technology Data Exchange (ETDEWEB)

    Oe, S. [Honshu-Shikoku Bridge Authority, Tokyo (Japan)

    1996-05-25

    The Akashi straits bridge is the Kobe-Naruto route of the bridge connecting Honshu and Shikoku; the bridge links Kobe in Hyogo prefecture with Awaji Island and, when completed, it will be a 3-span 2-hinge suspension bridge with the longest center effective span in the world. This report centers on the outline of the construction of stiffening girders for the Akashi straits bridge and especially on the characteristics of the engineering method newly employed. As the method of installing the stiffening girders, an overhang installation of face bars was employed which was a time-tested method. As the installing direction of the side spans, it was decided to install them from the anchorage to the tower. At the beginning, six large block installations were performed. A special balance was developed for the installation of short hanger parts for the purpose of enhancing safety and reduction in the process. A rubber-tired transporting truck was adopted for transporting members of framework on the bridge. GPS survey was used as a method for surveying the configuration. The subject engineering method was based on the construction of suspension bridge stiffening trusses in the past Honshu-Shikoku connecting bridge and reinforced with the improvements as above. Since the bridge is in the middle of construction, a subsequent report will hopefully be made on the actual results of the installation and the spanning after the closure. 8 figs., 2 tabs.

  4. Experimental study and stress analysis of rock bolt anchorage performance

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2014-10-01

    Full Text Available A new method was developed to apply pull-and-shear loads to the bolt specimen in order to evaluate the anchorage performance of the rebar bolt and the D-Bolt. In the tests, five displacing angles (0°, 20°, 40°, 60°, and 90°, two joint gaps (0 mm and 30 mm, and three kinds of host rock materials (weak concrete, strong concrete, and concrete-granite were considered, and stress–strain measurements were conducted. Results show that the ultimate loads of both the D-Bolt and the rebar bolt remained constant with any displacing angles. The ultimate displacement of the D-Bolt changed from 140 mm at the 0° displacing angle (pure pull to approximately 70 mm at a displacing angle greater than 40°. The displacement capacity of the D-Bolt is approximately 3.5 times that of the rebar bolt under pure pull and 50% higher than that of the rebar bolt under pure shear. The compressive stress exists at 50 mm from the bolt head, and the maximum bending moment value rises with the increasing displacing angle. The rebar bolt mobilises greater applied load than the D-Bolt when subjected to the maximum bending. The yielding length (at 0° of the D-Bolt is longer than that of the rebar bolt. The displacement capacity of the bolts increased with the joint gap. The bolt subjected to joint gap effect yields more quickly with greater bending moment and smaller applied load. The displacement capacities of the D-Bolt and the rebar bolt are greater in the weak host rock than that in the hard host rock. In pure shear condition, the ultimate load of the bolts slightly decreases in the hard rock. The yielding speed in the hard rock is higher than that in the weak rock.

  5. Thick-Walled Cylinder Theory Applied on a Conical Wedge Anchorage

    DEFF Research Database (Denmark)

    Bennitz, Anders; Grip, Niklas; Schmidt, Jacob Wittrup

    2011-01-01

    Conical wedge anchorages are frequently used to anchor steel tendons in prestressing applications within the construction industry. To replace the steel tendons with non-corrosive and low weight FRPs (Fiber Reinforced Polymers), the different mechanical interactions between the steel and FRPs call...... for further development of the anchorage.In this paper, we derive and examine an analytical model for the internal stresses and strains within the anchorage for a prescribed presetting distance. This model is derived from the theory of thick walled cylinders under the assumptions regarding plane stress...... and axial symmetry. We simplify the resulting system of ten nonlinear equations and derive a method for solving them numerically. A comparison of plotted results for three different angles on the wedge’s outer surface and six different presetting distances follows.These results are also compared to both axi...

  6. Bio-cultural anchorage of the prickly pear cactus in Tlalnepantla (Morelos), Mexico

    OpenAIRE

    Torres-Salcido, Gerardo; Ramos-Chávez, Alejandro; Urreta-Fernández, Álvaro

    2016-01-01

    The prickly pear cactus is a source of food with strong bio-cultural anchorage in Mexico. This is due to at least three factors: 1) the nature and heritage of cacti; 2) cultural heritage; and 3) the socio-cultural relationships with historical and symbolic roots that have facilitated knowledge of how to cultivate it and how to use it. The aim of this article is to put factors of territorial anchorage and its historical transformation in context by examining the case of the municipality of Tla...

  7. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...

  8. 77 FR 35104 - Notice of Request To Release Airport Property at Merrill Field Airport, Anchorage, AK

    Science.gov (United States)

    2012-06-12

    ... Anchorage, Alaska, on June 6, 2012. Byron K. Huffman, Division Manager, FAA, Alaskan Region. BILLING CODE... lands in accordance with Title 23, Part 710.509 of the Code of Federal Regulations and Section 6.13 of...-26, ARD. In accordance with Title 49 of the United States Code (U.S.C.), Section 47107(h)(2),...

  9. Experimental evidence of pharmacological management of anchorage in Orthodontics: A systematic review

    Science.gov (United States)

    Fernández-González, Felipe José; Cañigral, Aránzazu; Balbontín-Ayala, Felipe; Gonzalo-Orden, José Manuel; de Carlos, Felix; Cobo, Teresa; Fernández-Vázquez, Jose Pedro; Sánchez-Lasheras, Fernando; Vega, José Antonio

    2015-01-01

    Introduction: Orthodontic anchorage is one of the most challenging aspects of Orthodontics. Preventing undesired movement of teeth could result in safer and less complicated orthodontic treatment. Recently, several reviews have been published about the effects of different molecules on bone physiology and the clinical side effects in Orthodontics. However, the effects of local application of these substances on the rate of orthodontic tooth movement have not been assessed. Objectives: The aim of this research was to analyze the scientific evidence published in the literature about the effects of different molecules on orthodontic anchorage. Methods: The literature was systematically reviewed using PubMed/Medline, Scopus and Cochrane databases from 2000 up to July 31st, 2014. Articles were independently selected by two different researchers based on previously established inclusion and exclusion criteria, with a concordance Kappa index of 0.86. The methodological quality of the reviewed papers was performed. Results: Search strategy identified 270 articles. Twenty-five of them were selected after application of inclusion/exclusion criteria, and only 11 qualified for final analysis. Molecules involved in orthodontic anchorage were divided into three main groups: osteoprotegerin (OPG), bisphosphonates (BPs) and other molecules (OMs). Conclusions: Different drugs are able to alter the bone remodeling cycle, influencing osteoclast function and, therefore, tooth movement. Thus, they could be used in order to provide maximal anchorage while preventing undesired movements. OPG was found the most effective molecule in blocking the action of osteoclasts, thereby reducing undesired movements. PMID:26560822

  10. Extraction treatment of an adult patient with severe bimaxillary dentoalveolar protrusion using microscrew anchorage

    Institute of Scientific and Technical Information of China (English)

    OUYANG Li; ZHOU Yan-heng; FU Min-kui; DING Peng

    2007-01-01

    @@ Bimaxillary dentoalveolar protrusion is one of the most prevalent malocclusion in Asian population,1 Traditionally, orthodontic treatment often involves the extraction of four first premolars2 and demands the least amount of anchorage loss, therefore headgear used to be an unavoid- able fate of these patients.

  11. 75 FR 23804 - Notice of Inventory Completion: Alaska State Office, Bureau of Land Management, Anchorage, AK...

    Science.gov (United States)

    2010-05-04

    ... National Park Service Notice of Inventory Completion: Alaska State Office, Bureau of Land Management... completion of an inventory of human remains and associated funerary objects in the control of the U.S. Department of the Interior, Bureau of Land Management, Alaska State Office, Anchorage, AK, and in...

  12. 76 FR 80394 - Notice of Inventory Completion: Alaska State Office, Bureau of Land Management, Anchorage, AK

    Science.gov (United States)

    2011-12-23

    ... Inventory Completion: Alaska State Office, Bureau of Land Management, Anchorage, AK AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Alaska State Office, Bureau of Land Management has... completion of an inventory of human remains in the control of the Bureau of Land Management (BLM) that...

  13. 33 CFR 110.220 - Pacific Ocean at San Nicolas Island, Calif.; restricted anchorage areas.

    Science.gov (United States)

    2010-07-01

    ... Pacific Ocean at San Nicolas Island, Calif.; restricted anchorage areas. (a) The restricted areas—(1) East area. All waters within a circle having a radius of one nautical mile centered at latitude 33°13′45... approximately 101°, 420 yards, from San Nicolas Island East End Light. (2) West area. Shoreward of a...

  14. Three-dimensional finite element analysis of a newly designed onplant miniplate anchorage system.

    Science.gov (United States)

    Liu, Lin; Qu, Yin-Ying; Jiang, Li-Jun; Zhou, Qian; Tang, Tian-Qi

    2016-06-01

    The purpose of this research was to evaluate the structural stress and deformation of a newly designed onplant miniplate anchorage system compared to a standard anchorage system. A bone block integrated with a novel miniplate and fixation screw system was simulated in a three-dimensional model and subjected to force at different directions. The stress distribution and deformation of the miniplate system and cortical bone were evaluated using the three-dimensional finite element method. The results showed that the stress on the plate system and bone was linearly proportional to the force magnitude and was higher when the force was in a vertical direction (Y-axis). Stress and deformation values of the two screws (screw 1 and 2) were asymmetric when the force was added along Y-axis and was greater in screw 1. The highest deformation value of the screws was 7.5148 μm, much smaller than the limit value. The load was decreased for each single miniscrew, and the ability of the new anchorage system to bear the load was also enhanced to some degree. It was suggested that the newly designed onplant miniplate anchorage system is effective, easily implanted and minimally invasive.

  15. Oxidative Stress Modulates DNA Methylation during Melanocyte Anchorage Blockade Associated with Malignant Transformation

    Directory of Open Access Journals (Sweden)

    Ana C.E. Campos

    2007-12-01

    Full Text Available Both oxidative/nitrosative stress and alterations in DNA methylation are observed during carcinogenesis of different tumor types, but no clear correlation between these events has been demonstrated until now. Melanoma cell lines were previously established after submitting the nontumorigenic melanocyte lineage, melan-a, to cycles of anchorage blockade. In this work, increased intracellular oxidative species and nitric oxide levels, as well as alterations in the DNA methylation, were observed after melan-a detachment, which were also associated with a decrease in intracellular homocysteine (Hey, an element in the methionine (universal methyl donor cycle. This alteration was accompanied by increase in glutathione (GSH levels and methylated DNA content. Furthermore, a significant increase in dnmti and 3b expression was identified along melan-a anchorage blockade. LG-Nitro-L-arginine methyl esther (L-NAME, known as a nitric oxide synthase (NOS inhibitor, and N-acetyl-L-cysteine (NAC prevented the increase in global DNA methylation, as well as the increase in dnmti and 3b expression, observed during melan-a detachment. Interestingly, both L-NAME and NAC did not inhibit nitric oxide (NO production in these cells, but abrogated superoxide anion production during anchorage blockade. In conclusion, oxidative stress observed during melanocyte anchorage blockade seems to modulate DNA methylation levels and may directly contribute to the acquisition of an anoikis-resistant phenotype through an epigenetic mechanism.

  16. Biofilm formation on surface characterized micro-implants for skeletal anchorage in orthodontics

    NARCIS (Netherlands)

    Chin, Yeen; Sandham, John; de Vries, Jacob; van der Mei, Henderina; Busscher, Hendrik

    2007-01-01

    Micro-implants are increasingly popular in clinical orthodontics to effect skeletal anchorage. However, biofilm formation on their surfaces and subsequent infection of peri-implant tissues can result in either exfoliation or surgical removal of these devices. The present study aimed to assess biofil

  17. Are orthodontic distalizers reinforced with the temporary skeletal anchorage devices effective?

    NARCIS (Netherlands)

    Fudalej, P.S.; Antoszewska, J.

    2011-01-01

    INTRODUCTION: Our objective was to perform a systematic review of studies pertaining to the distalization of teeth with appliances reinforced with temporary skeletal anchorage devices. METHODS: PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Knowledge, Ovid, and Scopus were se

  18. Evaluating School Wellness Policy in Curbing Childhood Obesity in Anchorage, Alaska

    Science.gov (United States)

    Parsons, Wendy G.; Garcia, Gabriel M.; Hoffman, Pamela K.

    2014-01-01

    In 2006, the Anchorage School District implemented a school wellness policy to address the problem of obesity among its elementary-aged students. We assessed whether the addition of this policy is effective in protecting or preventing students from becoming overweight/obese over time. The methods involved following two cohorts of students for 5…

  19. Study of the aerostatic and aerodynamic stability of super long-span cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    Zhang Xinjun; Sun Hailing

    2014-01-01

    With the increase of span length,the bridge tends to be more flexible,and the wind stability be-comes an important problem for the design and construction of super long-span cable-stayed bridges. By taking a super long-span cable-stayed bridge with a main span of 1 400 m as example,the aerostatic and aerodynamic stability of the bridge are investigated by three-dimensional nonlinear aerostatic and aerodynamic stability analy-sis,and the results are compared with those of a suspension bridge with a main span of 1 385 m,and from the aspect of wind stability,the feasibility of using cable-stayed bridge in super long-span bridge with a main span above 1 000 m is discussed. In addition,the influences of design parameters including the depth and width of the girder,the tower structure,the tower height-to-span ratio,the side-to-main span ratio,the auxiliary piers in the side span and the anchorage system of stay cables,etc on the aerostatic and aerodynamic stability of su-per long-span cable-stayed bridges are investigated numerically;the key design parameters are pointed out,and also their reasonable values are proposed.

  20. Bridges in Complex Networks

    CERN Document Server

    Wu, Ang-Kun; Liu, Yang-Yu

    2016-01-01

    A bridge in a graph is an edge whose removal disconnects the graph and increases the number of connected components. We calculate the fraction of bridges in a wide range of real-world networks and their randomized counterparts. We find that real networks typically have more bridges than their completely randomized counterparts, but very similar fraction of bridges as their degree-preserving randomizations. We define a new edge centrality measure, called bridgeness, to differentiate the importance of a bridge in damaging a network. We find that certain real networks have very large average and variance of bridgeness compared to their degree-preserving randomizations and other real networks. Finally, we offer an analytical framework to calculate the bridge fraction and average bridgeness for uncorrelated random networks with arbitrary degree distributions.

  1. 钢锚梁式钢-混组合索塔锚固体系设计与分析%Design and Analysis of Steel-concrete Composite Anchorage Structure with Steel Anchor Beam

    Institute of Scientific and Technical Information of China (English)

    苗通; 孙蕊鑫

    2015-01-01

    A bridge is a twin towers and double cable plane prestressed concrete girder cable -stayed bridge with a span arrangement of (130 +300 +130)m,and the tower type is inverted Y and the Steel -concrete Composite anchorage structure with Steel Anchor Beam is used to anchorage the cable of end of the tower.Among this type anchorage system,the anchor boxes have been welded on both sides of the steel anchor beam,at the same time, using steel bracket to replace traditional concrete corbel structure.In this paper,the characteristics of this kind of anchor system has been introduced and the stress situation of this kind of anchor system has been analyzed u-sing the finite element method.The research conclusion can provide a reference for the design of this type of ca-ble pylon anchorage system.%某斜拉桥主桥是一座跨径布置为(130m +300m +130m)的双塔双索面预应力混凝土梁斜拉桥,索塔采用倒 Y 型,斜拉索在桥塔端采用新型空间索面钢锚梁式钢-混组合索塔锚固体系进行锚固。该型锚固体系将锚箱焊在钢锚梁两侧,同时采用钢牛腿替换传统的混凝土牛腿结构,提高了施工速度,改善了结构受力。介绍了该种锚固体系的特点,并采用有限元方法对改型索塔锚固体系的受力情况进行了分析,可为该类型索塔锚固体系设计提供参考。

  2. The benefit of differential moment concept in managing posterior anchorage and avoiding bite deepening

    Directory of Open Access Journals (Sweden)

    Harryanto Wijaya

    2012-09-01

    Full Text Available Background: Anchorage is one of the major concerns in orthodontic space closure. Various methods have been proposed to enhance posterior anchorage in space closure such as headgear, Nance holding appliance, and micro implant as temporary anchorage devices. However, several issues such as patient's compliance, appliance effectiveness, and cost of the device become many clinicians concern. The differential moment concept in segmented arch is a technique that requires no patient compliance but can effectively manage posterior anchorage and avoid bite deepening by careful application of forces and moments. Purpose: The purpose of this case report is to show the use of differential moment concept in segmented arch technique to manage posterior anchorage and to avoid bite deepening. Case: A 21 years old female patient with protrusive teeth as her chief complaint was treated using fixed orthodontic appliance. Case management: The treatment included four first bicuspid extraction and space closure utilizing differential moment concept in segmented arch. Conclusion: It can be concluded that application of differential moment concept in segmented arch technique is a non invasive, compliance independent, effective, and cost efficient method to manage posterior anchorage and to avoid bite deepening.latar belakang: Penjangkaran merupakan salah satu aspek yang sering kali menjadi masalah dalam penutupan ruang pada perawatan ortodonti. Berbagai metode disarankan untuk memperkuat penjangkaran posterior dalam penutupan ruang seperti headgear, piranti penahan Nance, dan implan mikro sebagai alat penjangkar sementara. Namun demikian, beberapa hal seperti kerjasama pasien, efektivitas piranti, dan biaya dari alat-alat tersebut sering menjadi perhatian/pertimbangan bagi klinisi. Konsep momen diferensial pada segmented arch adalah suatu cara yang efektif untuk memperkuat penjangkaran dan menghindari pendalaman gigitan tanpa memerlukan kerjasama pasien. tujuan

  3. Taizhou Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Taizhou Bridge lies between Taizhou, Zhenjiang and Changzhou City in Jiangsu Province. The total length of Taizhou Bridge is 62.088 kin. The whole line is designed by freeway codes with six lanes in two directions. The wholeinvestment is 9.37 billion RMB and the planned construction duration is 5.5 years. The main bridge crossing the Yangtze River is a continuous three-pylon two-span suspension bridge with the main span of 1 080 m. The bridge system is realized for the first time and ranks first in the world until now.

  4. Anchorage of titanium implants with different surface characteristics: an experimental study in rabbits

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2000-01-01

    ) TiO2-blasted with particles of grain size 10 to 53 microns; (3) TiO2-blasted, grain size 63 to 90 microns; (4) TiO2-blasted, grain size 90 to 125 microns; (5) titanium plasma-sprayed (TPS). The surface topography was determined by the use of an optical instrument. Twelve rabbits, divided into two...... in group B were 9 and 12 weeks. The tibiae were removed, and each implant site was dissected, fixed, and embedded in light-curing resin. Ground sections were made, and the peri-implant bone was analyzed using fluorescence and light microscopy. RESULTS: The turned implants had the lowest Sa and Sy values......: The present study demonstrated that a clear relation exists between surface roughness, described in Sa values, and implant anchorage assessed by RMT measurements. The anchorage appeared to increase with the maturation of bone tissue during healing....

  5. A genetic algorithm for dynamic parameters reverse deduction of integrated anchorage system

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In the analysis of the system of anchoring bar and wall rock in small strain and longitudinal vibration dynamic response, the influence of the cement grouting as well as the rock layer on the anchor bar can be evaluated as the two kinds of parameters: the dynamic stiffness and the damp, which are the vital reference of the anchorage quality. Based on the analytic solution to the dynamic equation of the integrated anchor bar, the new approach which combines genetic algorithm and the toolbox of Matlab is applied to solve the problem of multi-parameters reverse deduction for integrated anchorage system in dynamic testing. Using the traits of the self-organizing, self-adapting and the fast convergence speed of the genetic algorithm, the optimum of all possible solutions to dynamic parameters is obtained by calculating the project instances. Examples show that the method presented in this paper is effective and reliable.

  6. Numerical implementation of multiple peeling theory and its application to spider web anchorages.

    Science.gov (United States)

    Brely, Lucas; Bosia, Federico; Pugno, Nicola M

    2015-02-06

    Adhesion of spider web anchorages has been studied in recent years, including the specific functionalities achieved through different architectures. To better understand the delamination mechanisms of these and other biological or artificial fibrillar adhesives, and how their adhesion can be optimized, we develop a novel numerical model to simulate the multiple peeling of structures with arbitrary branching and adhesion angles, including complex architectures. The numerical model is based on a recently developed multiple peeling theory, which extends the energy-based single peeling theory of Kendall, and can be applied to arbitrarily complex structures. In particular, we numerically show that a multiple peeling problem can be treated as the superposition of single peeling configurations even for complex structures. Finally, we apply the developed numerical approach to study spider web anchorages, showing how their function is achieved through optimal geometrical configurations.

  7. Inclusion of CFRP-Epoxy Composite for End Anchorage in NSM-Epoxy Strengthened Beams

    Directory of Open Access Journals (Sweden)

    Md. Akter Hosen

    2015-01-01

    Full Text Available Nowadays, the use of near surface mounted (NSM technique strengthening reinforced concrete (RC structural members is going very popular. The failure modes of NSM strengthened reinforced concrete (RC beams have been shown to be largely due to premature failure such as concrete cover separation. In this study, CFRP U-wrap end anchorage with CFRP fabrics was used to eliminate the concrete cover separation failure. A total of eight RC rectangular beam specimens of 125 mm width, 250 mm depth, and 2300 mm length were tested. One specimen was kept unstrengthened as a reference; three specimens were strengthened with NSM steel bars and the remaining four specimens were strengthened with NSM steel bars together with the U-wrap end anchorage. The experimental results showed that wrapped strengthened beams had higher flexural strength and superior ductility performance. The results also show that these beams had less deflection, strain, crack width, and spacing.

  8. Impedance-Based Cable Force Monitoring in Tendon-Anchorage Using Portable PZT-Interface Technique

    Directory of Open Access Journals (Sweden)

    Thanh-Canh Huynh

    2014-01-01

    Full Text Available In this paper, a portable PZT interface for tension force monitoring in the cable-anchorage subsystem is developed. Firstly, the theoretical background of the impedance-based method is presented. A few damage evaluation approaches are outlined to quantify the variation of impedance signatures. Secondly, a portable PZT interface is designed to monitor impedance signatures from the cable-anchorage subsystem. One degree-of-freedom analytical model of the PZT interface is established to explain how to represent the loss of cable force from the change in the electromechanical impedance of the PZT interface as well as reducing the sensitive frequency band by implementing the interface device. Finally, the applicability of the proposed PZT-interface technique is experimentally evaluated for cable force-loss monitoring in a lab-scaled test structure.

  9. Impedance monitoring at tendon-anchorage via mountable PZT interface and temperature-effect compensation

    Science.gov (United States)

    Huynh, Thanh-Canh; Nguyen, Tuan-Cuong; Choi, Sang-Hoon; Kim, Jeong-Tae

    2016-04-01

    In this study, the pre-stress force in pre-stressed concrete (PSC) girders is monitored via mountable PZT interface under varying temperature. Firstly, an impedance-based technique using mountable PZT interface is proposed for pre-stress-loss monitoring in tendon-anchorage systems. A cross correlation-based temperature-effect compensation algorithm using an effective frequency shift (EFS) of impedance signatures is visited. Secondly, lab-scale experiments are performed on a PSC girder instrumented with a mountable PZT interface at tendon-anchorage. A series of temperature variation and pre-stress-loss events are simulated for the lab-scale PSC girder. Thirdly, the feasibility of the mountable PZT interface for pre-stress-loss monitoring in tendon-anchorage is experimentally verified under constant temperature conditions. Finally, the PZT interface device is examined for pre-stress-loss monitoring under temperature changes to validate its applicability. The temperature effect on impedance signatures is compensated by minimizing cross-correlation deviation between impedance patterns of the mountable PZT interface.

  10. Strontium ranelate improved tooth anchorage and reduced root resorption in orthodontic treatment of rats.

    Science.gov (United States)

    Kirschneck, Christian; Wolf, Michael; Reicheneder, Claudia; Wahlmann, Ulrich; Proff, Peter; Roemer, Piero

    2014-12-05

    The anchorage mechanisms currently used in orthodontic treatment have various disadvantages. The objective of this study was to determine the applicability of the osteoporosis medication strontium ranelate in pharmacologically induced orthodontic tooth anchorage. In 48 male Wistar rats, a constant orthodontic force of 0.25 N was reciprocally applied to the upper first molar and the incisors by means of a Sentalloy(®) closed coil spring for two to four weeks. 50% of the animals received strontium ranelate at a daily oral dosage of 900 mg per kilogramme of body weight. Bioavailability was determined by blood analyses. The extent of tooth movement was measured both optometrically and cephalometrically (CBCT). Relative alveolar gene expression of osteoclastic markers and OPG-RANKL was assessed by qRT-PCR and root resorption area and osteoclastic activity were determined in TRAP-stained histologic sections of the alveolar process. Compared to controls, the animals treated with strontium ranelate showed up to 40% less tooth movement after four weeks of orthodontic treatment. Gene expression and histologic analyses showed significantly less osteoclastic activity and a significantly smaller root resorption area. Blood analyses confirmed sufficient bioavailability of strontium ranelate. Because of its pharmacologic effects on bone metabolism, strontium ranelate significantly reduced tooth movement and root resorption in orthodontic treatment of rats. Strontium ranelate may be a viable agent for inducing tooth anchorage and reducing undesired root resorption in orthodontic treatment. Patients under medication of strontium ranelate have to expect prolonged orthodontic treatment times.

  11. Fatigue of threaded rods in cable anchorages due to Vortex shedding

    NARCIS (Netherlands)

    Maljaars, J.; Snijder, H.H.

    2013-01-01

    The 'Hovenring' is a bicycle roundabout flyover built as a signature bridge with a central steel pylon carrying a circular bridge deck suspended through stay-cables. Shortly after installation of the bridge, the stay-cables turned out to vibrate in the wind due to vortex shedding. These vibrations h

  12. Sustainable Bridge Infrastructure Procurement

    DEFF Research Database (Denmark)

    Safi, Mohammed; Du, Guangli; Simonsson, Peter

    2016-01-01

    The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a holistic approach that agencies could use...... to procure the most “sustainable” (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering all the main aspects: life-cycle cost (LCC), service life-span, aesthetic demands and environmental impacts (LCA)....

  13. Bridge Crossing Simulator

    Science.gov (United States)

    2014-10-07

    Requirement BCS Computer-controlled hydraulic actuation system to impart simulated crossing loads on an entire bridge structure undergoing fatigue test ...structure. Bridge test site with prepared embankments corresponding to the span and bank condition requirements of the bridge under test Conduct real...Center (AEC). (5) Sample size and number of crossings required. The number of required simulated crossings to conduct fatigue testing per the

  14. Bridging the Gap

    OpenAIRE

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska; Murdock, Karen; Schmidt, Iben Julie

    2015-01-01

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures. Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ve...

  15. Bridging the Gap

    DEFF Research Database (Denmark)

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska;

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

  16. Semiconductor bridge (SCB) detonator

    Science.gov (United States)

    Bickes, Jr., Robert W.; Grubelich, Mark C.

    1999-01-01

    The present invention is a low-energy detonator for high-density secondary-explosive materials initiated by a semiconductor bridge igniter that comprises a pair of electrically conductive lands connected by a semiconductor bridge. The semiconductor bridge is in operational or direct contact with the explosive material, whereby current flowing through the semiconductor bridge causes initiation of the explosive material. Header wires connected to the electrically-conductive lands and electrical feed-throughs of the header posts of explosive devices, are substantially coaxial to the direction of current flow through the SCB, i.e., substantially coaxial to the SCB length.

  17. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated...

  18. Effectiveness of interceptive treatment of class III malocclusions with skeletal anchorage: A systematic review and meta-analysis

    Science.gov (United States)

    Rodríguez de Guzmán-Barrera, Jorge; Sáez Martínez, Carla; Boronat-Catalá, Montserrat; Montiel-Company, Jose María; Paredes-Gallardo, Vanessa; Gandía-Franco, José Luís; Almerich-Silla, José Manuel; Bellot-Arcís, Carlos

    2017-01-01

    Recently, new strategies for treating class III malocclusions have appeared. Skeletal anchorage appears to reduce the dentoalveolar effects while maximising the orthopaedic effect in growing patients. The purpose of this systematic review and meta-analysis is to examine the effectiveness of bone anchorage devices for interceptive treatment of skeletal class III malocclusions. Searches were made in the Pubmed, Embase, Scopus and Cochrane databases, as well as in a grey literature database, and were complemented by hand-searching. The criteria for eligibility were: patients who had undergone orthodontic treatment with skeletal anchorage (miniplates and miniscrews). Patients with syndromes or craniofacial deformities or who had undergone maxillofacial surgery were excluded. The following variables were recorded for each article: author, year of publication, type of study, sample size, dropouts, demographic variables, treatment carried out, radiographic study (2D or 3D), follow-up time, and quality of the articles on the Newcastle-Ottawa Scale. The means and confidence intervals of the following variables were employed: Wits, overjet, ANB, SNA and SNB. Initially, 239 articles were identified. After removing the duplicates and applying the selection criteria, 9 were included in the qualitative synthesis and 7 in the quantitative synthesis (meta-analysis). It may be concluded that skeletal anchorage is an effective treatment for improving skeletal Class III malocclusion, but when compared with other traditional treatments such as disjunction and face mask, there is no clear evidence that skeletal anchorage improves the results. PMID:28328995

  19. Detection of bond failure in the anchorage zone of reinforced concrete beams via acoustic emission monitoring

    Science.gov (United States)

    Abouhussien, Ahmed A.; Hassan, Assem A. A.

    2016-07-01

    In this study, acoustic emission (AE) monitoring was utilised to identify the onset of bond failure in reinforced concrete beams. Beam anchorage specimens were designed and tested to fail in bond in the anchorage zone. The specimens included four 250 × 250 × 1500 mm beams with four variable bonded lengths (100, 200, 300, and 400 mm). Meanwhile, an additional 250 × 250 × 2440 mm beam, with 200 mm bonded length, was tested to investigate the influence of sensor location on the identification of bond damage. All beams were tested under four-point loading setup and continuously monitored using three distributed AE sensors. These attached sensors were exploited to record AE signals resulting from both cracking and bond deterioration until failure. The variations in the number of AE hits and cumulative signal strength (CSS) versus test time were evaluated to achieve early detection of crack growth and bar slippage. In addition, AE intensity analysis was performed on signal strength of collected AE signals to develop two additional parameters: historic index (H (t)) and severity (S r). The analysis of these AE parameters enabled an early detection of both first cracks (at almost the mid-span of the beam) and bar slip in either of the anchorage zones at the beams’ end before their visual observation, regardless of sensor location. The results also demonstrated a clear correlation between the damage level in terms of crack development/measured free end bar slip and AE parameters (number of hits, CSS, H(t), and S r).

  20. Impact of a new gasoline benzene regulation on ambient air pollutants in Anchorage, Alaska

    Science.gov (United States)

    Yano, Yuriko; Morris, Stephen S.; Salerno, Christopher; Schlapia, Anne M.; Stichick, Mathew

    2016-05-01

    The purpose of this study was to quantify the impact of a new U.S. Environmental Protection Agency (EPA) standard that limits the amount of benzene allowed in gasoline on ambient benzene concentrations. This new standard, together with two companion regulations that limit cold-temperature automotive emissions and the permeability of portable fuel containers, was expected to lower the levels of ambient benzene and other volatile organic compounds (VOCs) nationwide. In this study the impact of the gasoline benzene standard was evaluated in Anchorage, Alaska in a two-phase ambient air monitoring study conducted before and after the new gasoline standard was implemented. Gasoline sold by Anchorage retailers was also evaluated in each phase to determine the content of benzene and other gasoline components. The average benzene content in Anchorage gasoline was reduced by 70%, from 5.05% (w/w) to 1.53% (w/w) following the implementation of the standard. The annual mean ambient benzene concentration fell by 51%, from 0.99 ppbv in Phase 1 to 0.49 ppbv in Phase 2. Analysis suggests the change in gasoline benzene content alone reduced benzene emissions by 46%. The changes in toluene, ethylbenzene, and xylene content in gasoline between Phase 1 and 2 were relatively small and the differences in the mean ambient concentrations of these compounds between phases were modest. Our results suggest that cold winter communities in high latitude and mountainous regions may benefit more from the gasoline benzene standard because of high benzene emissions resulting from vehicle cold start and a tendency to develop atmospheric stagnation conditions in the winter.

  1. Concentrations of fecal coliform bacteria in creeks, Anchorage, Alaska, August and September 1998

    Science.gov (United States)

    Dorava, Joseph M.; Love, Andra

    1999-01-01

    Water samples were collected from five creeks in undeveloped, semi-developed, and developed areas of Anchorage, Alaska, during August and September 1998 to determine concentrations of fecal coliform bacteria. In undeveloped areas of Ship, Chester, and Campbell Creeks, and the semi-developed area of Rabbit Creek, concentrations of fecal coliform bacteria ranged from less than 1 to 16 colonies per 100 milliliters of water. In the semi-developed area of Little Rabbit Creek, concentrations ranged from 30 to 860 colonies per 100 milliliters of water. In developed areas of the creeks, concentrations of fecal coliform bacteria ranged from 6 to 80 colonies per 100 milliliters of water.

  2. Dental Extrusion with Orthodontic Miniscrew Anchorage: A Case Report Describing a Modified Method

    Directory of Open Access Journals (Sweden)

    Ricardo Fidos Horliana

    2015-01-01

    Full Text Available In recent years, the skeletal anchorage through miniscrews has expanded the treatment options in orthodontics (Yamaguchi et al., 2012. We hereby present a modified method for tooth extrusion for cases where crown-lengthening surgery is contraindicated for aesthetic reasons. This modified method uses three orthodontic appliances: a mini-implant, an orthodontic wire, and a bracket. The aim of this case report was to increase the length of the clinical crown of a fractured tooth (tooth 23 by means of an orthodontic extrusion with the modified method of Roth and Diedrich.

  3. Technical research on control of caisson construction for the middle tower foundation of Taizhou Bridge

    Institute of Scientific and Technical Information of China (English)

    Liu Jianbo; Yang Yanhua; Zhang Yongtao; Du Song

    2011-01-01

    The real-time informational monitoring system is adopted in the construction of middle tower foundation of Taizhou Bridge for the first time. The geometric state of the caisson, the stress of upstream and downstream anchorage cables, underwater topography, the drag forces of the caisson cutting edge and frictional resistances of the sidewall and etc. are monitored in real time. According to the synthesized data analysis and decision-making system, the spatial states of the caisson are adjusted in time to locate and embed the deep water caisson precisely. The offset error of the caisson is less than 30 cm and the vertical error is 1/363 at the final stage. The control technology for construction of large caisson under deep water is concluded and would be helpful for the construction of bridge foundation in the future.

  4. Bridge technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. As LANs have proliferated, new technologies and system concepts have come to the fore. One of the key issues is how to interconnect networks. One means of interconnection is to use a 'bridge'. Other competing technologies are repeaters, routers, and gateways. Bridges permit traffic isolation, connect network segments together and operate at the MAC layer. Further, because they operate at the MAC layer, they can handle a variety of protocols such as TCP/IP, SNA, and X.25. This report focuses on the specific technology of bridging two netw

  5. 重庆寸滩长江大桥主桥设计%Design of Main Bridge of Cuntan Changjiang River Bridge in Chongqing

    Institute of Scientific and Technical Information of China (English)

    唐贺强; 曹洪武; 万田保

    2013-01-01

    The main bridge of Cuntan Changjiang River Bridge in Chongqing is a single-span simply-supported steel box girder suspension bridge with span arrangement 250 m+880 m+250 m.The bridge has two main cables that are the structures of prefabricated parallel high-strength steel wire strands.There are totally 57 pairs of the suspenders arranged for the whole bridge,the suspenders are the structures of prefabricated parallel steel wire strands and are connected with the cable bands by way of pin connection.The tower saddles are the fully cast structures and under a tower saddle,the base plate is arranged and is used as the sliding set.The splay saddles are the base structures and under a splay saddle,the cylindrical steel bearing is arranged.The anchoring systems for the main cables are the shaped steel anchoring systems.The stiffening girder of the bridge is designed as the streamlined flat closed steel box girder that is 3.5 m deep and 42 m wide.The anchorage on both the south and north banks are the gravity anchorage,the foundation for each anchorage is the cast-in-situ enlarged foundation and the body of the anchorage is in U shape in plan.The towers are the reinforced concrete portal frame structures.The two columns of a tower are arranged vertically and the foundation of the tower is the pile foundation with separated pile caps.%重庆寸滩长江大桥主桥为250m+880m+250m的单跨简支钢箱梁悬索桥.该桥设2根主缆,主缆采用预制平行高强钢丝索股结构.全桥共布置57对吊索,吊索采用预制平行钢丝束,与索夹采用销接式连接方式.主索鞍为全铸式结构,鞍底设置座板作为滑动副.散索鞍为底座式结构,底部设置柱面钢支座.主缆锚固系统采用型钢锚固系统.加劲梁采用流线型扁平式封闭钢箱梁,梁高3.5m,宽42 m.南、北锚碇均为重力式锚碇,现浇扩大基础,锚体在平面均呈U形.桥塔为钢筋混凝土门式框架结构,两塔柱竖直布置,基础为分离式承台桩基础.

  6. Increasing the Capacity of Existing Bridges by Using Unbonded Prestressing Technology: A Case Study

    Directory of Open Access Journals (Sweden)

    Antonino Recupero

    2014-01-01

    Full Text Available External posttensioning or unbonded prestressing was found to be a powerful tool for retrofitting and for increasing the life extension of existing structures. Since the 1950s, this technique of reinforcement was applied with success to bridge structures in many countries, and was found to provide an efficient and economic solution for a wide range of bridge types and conditions. Unbonded prestressing is defined as a system in which the post-tensioning tendons or bars are located outside the concrete cross-section and the prestressing forces are transmitted to the girder through the end anchorages, deviators, or saddles. In response to the demand for a faster and more efficient transportation system, there was a steady increase in the weight and volume of traffic throughout the world. Besides increases in legal vehicle loads, the overloading of vehicles is a common problem and it must also be considered when designing or assessing bridges. As a result, many bridges are now required to carry loads significantly greater than their original design loads; and their deck results still deteriorated by cracking of concrete, corrosion of rebars, snapping of tendons, and so forth. In the following, a case study about a railway bridge retrofitted by external posttensioning technique will be illustrated.

  7. Patients’ and orthodontists’ perceptions of miniplates used for temporary skeletal anchorage: A prospective study

    Science.gov (United States)

    Cornelis, Marie A.; Scheffler, Nicole R.; Nyssen-Behets, Catherine; De Clerck, Hugo J.; Tulloch, J. F. Camilla

    2009-01-01

    Introduction Temporary skeletal anchorage is a relatively recent addition to orthodontic treatment. Surgical miniplates, modified with intraoral attachments, provide an alternative to miniscrews for skeletal anchorage. In this study, we wanted to determine patients’ and providers’ perceptions of miniplate use during orthodontic treatment. Methods Consecutive patients having miniplates placed as part of their treatment completed questionnaires about their experiences during surgery and orthodontic treatment. A total of 200 miniplates were placed for 97 patients. The 30 orthodontists treating these patients also completed questionnaires concerning miniplate success, handling complexity, and whether these devices simplified treatment. Results The success rate was 92.5%. The devices were well tolerated by the patients. After a year, 72% of the patients reported that they did not mind having the implant, and 82% said that the surgical experience was better than expected, with little or no pain. The most frequent problems were postsurgical swelling, lasting 5 days on average, and cheek irritation experienced initially by more than a third of the patients, but it lessened over time. The clinicians reported that these devices were easy to use and greatly simplified orthodontic treatment. Conclusions Miniplates are well accepted by patients and providers and are a safe and effective adjunct for complex orthodontic treatments. PMID:18174066

  8. Modified Miniplates for Temporary Skeletal Anchorage in Orthodontics: Placement and Removal Surgeries

    Science.gov (United States)

    Cornelis, Marie A.; Scheffler, Nicole R.; Mahy, Pierre; Siciliano, Sergio; De Clerck, Hugo J.; Tulloch, J.F. Camilla

    2009-01-01

    Purpose Skeletal anchorage systems are increasingly used in orthodontics. This article describes the techniques of placement and removal of modified surgical miniplates used for temporary orthodontic anchorage and reports surgeons’ perceptions of their use. Patients and Methods We enrolled 97 consecutive orthodontic patients having miniplates placed as an adjunct to treatment. A total of 200 miniplates were placed by 9 oral surgeons. Patients and surgeons completed questionnaires after placement and removal surgeries. Results Fifteen miniplates needed to be removed prematurely. Antibiotics and anti-inflammatories were generally prescribed after placement but not after removal surgery. Most surgeries were performed with the patient under local anesthesia. Placement surgery lasted on average between 15 and 30 minutes per plate and was considered by the surgeons to be very easy to moderately easy. The surgery to remove the miniplates was considered easier and took less time. The patients’ chief complaint was swelling, lasting on average 5.3 ± 2.8 days after placement and 4.5 ± 2.6 days after removal. Conclusions Although miniplate placement/removal surgery requires the elevation of a flap, this was considered an easy and relatively short surgical procedure that can typically be performed with the patient under local anesthesia without complications, and it may be considered a safe and effective adjunct for orthodontic treatment. PMID:18571028

  9. Skeletal anchorage for orthodontic correction of severe maxillary protrusion after previous orthodontic treatment.

    Science.gov (United States)

    Tanaka, Eiji; Nishi-Sasaki, Akiko; Hasegawa, Takuro; Nishio, Clarice; Kawai, Nobuhiko; Tanne, Kazuo

    2008-01-01

    The correction of a severe maxillary protrusion in an adult by distal movement of the maxillary molars has been one of the most difficult biomechanical problems in orthodontics. This article reports on the treatment of an adult case of severe maxillary protrusion and a large overjet treated with a skeletal anchorage system. A female patient, age 22 years and 3 months, complained of the difficulty of lip closure due to severe maxillary protrusion with a gummy smile. Overjet and overbite were +7.6 mm and -0.9 mm, respectively. She had a history of orthodontic treatment in which her maxillary first premolars were extracted. In order to conduct distal movement of the maxillary molars, anchor plates were placed in the zygomatic process. After achieving a Class I molar relationship, retraction and intrusion of the maxillary incisors were performed. After a 2-year treatment, an acceptable occlusion was achieved with a Class I molar relationship. Her convex facial profile with upper lip protrusion was considerably improved, and the lips showed less tension in lip closure. After a 2-year retention period, an acceptable occlusion was maintained without recurrence of maxillary protrusion, indicating a stability of the occlusion. The result of this treatment indicated that skeletal anchorage is of great importance as a remedy for achieving intrusion and retraction of the maxillary incisors in cases of severe maxillary protrusion with a patient who had previous orthodontic treatment.

  10. Behaviour of plate anchorage in plate-reinforced composite coupling beams.

    Science.gov (United States)

    Lam, W Y; Li, Lingzhi; Su, R K L; Pam, H J

    2013-01-01

    As a new alternative design, plate-reinforced composite (PRC) coupling beam achieves enhanced strength and ductility by embedding a vertical steel plate into a conventionally reinforced concrete (RC) coupling beam. Based on a nonlinear finite element model developed in the authors' previous study, a parametric study presented in this paper has been carried out to investigate the influence of several key parameters on the overall performance of PRC coupling beams. The effects of steel plate geometry, span-to-depth ratio of beams, and steel reinforcement ratios at beam spans and in wall regions are quantified. It is found that the anchorage length of the steel plate is primarily controlled by the span-to-depth ratio of the beam. Based on the numerical results, a design curve is proposed for determining the anchorage length of the steel plate. The load-carrying capacity of short PRC coupling beams with high steel ratio is found to be controlled by the steel ratio of wall piers. The maximum shear stress of PRC coupling beams should be limited to 15 MPa.

  11. Prestressed CFRP Strips with Gradient Anchorage for Structural Concrete Retrofitting: Experiments and Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Julien Michels

    2014-01-01

    Full Text Available This paper presents a study on the load carrying capacity of reinforced concrete (RC beams strengthened with externally bonded (EB carbon fiber reinforced polymer (CFRP strips prestressed up to 0.6% in strain. At the strip ends, the innovative gradient anchorage is used instead of conventional mechanical fasteners. This method, based on the epoxy resin’s ability to rapidly cure under high temperatures, foresees a sector-wise heating followed by a gradual decrease of the initial prestress force towards the strip ends. The experimental investigation shows a promising structural behavior, resulting in high strip tensile strains, eventually almost reaching tensile failure of the composite strip. Additionally, ductility when considering deflection at steel yielding and at ultimate load is satisfying, too. From a practical point of view, it is demonstrated that premature strip grinding in the anchorage zone is not beneficial. In addition, a non-commercial 1D finite element code has been enlarged to an EB reinforcement with prestressed composite strips. A bilinear bond stress-slip relation obtained in earlier investigations is introduced as an additional failure criterion to the code. The numerical code is able to almost perfectly predict the overall structural behavior. Furthermore, the calculations are used for comparison purposes between an initially unstressed and a prestressed externally bonded composite reinforcement. The increase in cracking and yielding load, as well as differences in structural stiffness are apparent.

  12. Bridged Race Population Estimates

    Data.gov (United States)

    U.S. Department of Health & Human Services — Population estimates from "bridging" the 31 race categories used in Census 2000, as specified in the 1997 Office of Management and Budget (OMB) race and ethnicity...

  13. Bridging Humanism and Behaviorism.

    Science.gov (United States)

    Chu, Lily

    1980-01-01

    Humanistic behaviorism may provide the necessary bridge between behaviorism and humanism. Perhaps the most humanistic approach to teaching is to learn how certain changes will help students and how these changes can be accomplished. (Author/MLF)

  14. Germ Cell Intercellular Bridges

    Science.gov (United States)

    Greenbaum, Michael P.; Iwamori, Tokuko; Buchold, Gregory M.; Matzuk, Martin M.

    2011-01-01

    Stable intercellular bridges are a conserved feature of gametogenesis in multicellular animals observed more than 100 years ago, but their function was unknown. Many of the components necessary for this structure have been identified through the study of cytokinesis in Drosophila; however, mammalian intercellular bridges have distinct properties from those of insects. Mammalian germ cell intercellular bridges are composed of general cytokinesis components with additional germ cell–specific factors including TEX14. TEX14 is an inactive kinase essential for the maintenance of stable intercellular bridges in gametes of both sexes but whose loss specifically impairs male meiosis. TEX14 acts to impede the terminal steps of abscission by competing for essential component CEP55, blocking its interaction in nongerm cells with ALIX and TSG101. Additionally, TEX14-interacting protein RBM44, whose localization in stabile intercellular bridges is limited to pachytene and secondary spermatocytes, may participate in processes such as RNA transport but is nonessential to the maintenance of intercellular bridge stability. PMID:21669984

  15. Long Span Bridges in Scandinavia

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1998-01-01

    The first Scandinavian bridge with a span of more than 500 m was the Lillebælt Suspension Bridge opened to traffic in 1970.Art the end of the 20th century the longest span of any European bridge is found in the Storebælt East Bridge with a main span of 1624 m. Also the third longest span in Europe...... is found in Scandinavia - the 1210 m span of the Höga Kusten Bridge in Sweden.The Kvarnsund Bridge in Norway was at the completion in 1991 the longest cable-stayed bridge in the world, and the span of 530 m is still thge longest for cable-stayed bridges in concrete. The Øresund Bridge with its sapn of 490...... m is the longest among cable-stayed bridges for both road and railway traffic....

  16. 77 FR 66942 - Anchorages; Lower Mississippi River, Above Head of Passes, Convent, LA and Point Pleasant, LA

    Science.gov (United States)

    2012-11-08

    ... INFORMATION section below for instructions on submitting comments. To avoid duplication, please use only one... anchored or moored within the anchorage areas. D. Regulatory Analyses We developed this proposed rule after... Homeland Security Management Directive 023-01 and Commandant Instruction M16475.lD, which guide the...

  17. Retention of prolyl hydroxylase PHD2 in the cytoplasm prevents PHD2-induced anchorage-independent carcinoma cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Jokilehto, Terhi [Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku (Finland); Turku Graduate School of Biomedical Sciences, Turku (Finland); Hoegel, Heidi [Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku (Finland); Heikkinen, Pekka [Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku (Finland); Turku Graduate School of Biomedical Sciences, Turku (Finland); Rantanen, Krista [Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku (Finland); Elenius, Klaus [Department of Oncology and Radiotherapy, University of Turku and Turku University Hospital, Turku (Finland); Department of Medical Biochemistry and Genetics, University of Turku and Turku University Hospital, Turku (Finland); Sundstroem, Jari [Department of Pathology, University of Turku and Turku University Hospital, Turku (Finland); Jaakkola, Panu M. [Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku (Finland); Department of Oncology and Radiotherapy, University of Turku and Turku University Hospital, Turku (Finland)

    2010-04-15

    Cellular oxygen tension is sensed by a family of prolyl hydroxylases (PHD1-3) that regulate the degradation of hypoxia-inducible factors (HIF-1{alpha} and -2{alpha}). The PHD2 isoform is considered as the main downregulator of HIF in normoxia. Our previous results have shown that nuclear translocation of PHD2 associates with poorly differentiated tumor phenotype implying that nuclear PHD2 expression is advantageous for tumor growth. Here we show that a pool of PHD2 is shuttled between the nucleus and the cytoplasm. In line with this, accumulation of wild type PHD2 in the nucleus was detected in human colon adenocarcinomas and in cultured carcinoma cells. The PHD2 isoforms showing high nuclear expression increased anchorage-independent carcinoma cell growth. However, retention of PHD2 in the cytoplasm inhibited the anchorage-independent cell growth. A region that inhibits the nuclear localization of PHD2 was identified and the deletion of the region promoted anchorage-independent growth of carcinoma cells. Finally, the cytoplasmic PHD2, as compared with the nuclear PHD2, less efficiently downregulated HIF expression. Forced HIF-1{alpha} or -2{alpha} expression decreased and attenuation of HIF expression increased the anchorage-independent cell growth. However, hydroxylase-inactivating mutations in PHD2 had no effect on cell growth. The data imply that nuclear PHD2 localization promotes malignant cancer phenotype.

  18. 33 CFR 165.110 - Safety and Security Zone; Liquefied Natural Gas Carrier Transits and Anchorage Operations, Boston...

    Science.gov (United States)

    2010-07-01

    ...; Liquefied Natural Gas Carrier Transits and Anchorage Operations, Boston, Massachusetts. 165.110 Section 165... Limited Access Areas First Coast Guard District § 165.110 Safety and Security Zone; Liquefied Natural Gas... ahead and one mile astern, and 500 yards on each side of any liquefied natural gas carrier (LNGC)...

  19. The "Real Self" and Inauthenticity: The Importance of Self-Concept Anchorage for Emotional Experiences in the Workplace

    Science.gov (United States)

    Sloan, Melissa M.

    2007-01-01

    I examine the utility of self-concept anchorage (as described by Turner 1976) in the analysis of inauthenticity in the workplace. As controlling internally felt emotion may distance the worker from her true feelings or true self, the management of emotion in the workplace can produce feelings of inauthenticity in the worker. This relationship has…

  20. Non-destructive inspection protocol for reinforced concrete barriers and bridge railings

    Science.gov (United States)

    Chintakunta, Satish R.; Boone, Shane D.

    2014-02-01

    Reinforced concrete highway barriers and bridge railings serve to prevent errant vehicles from departing the travel way at grade separations. Despite the important role that they play in maintaining safety and their ubiquitous nature, barrier inspection rarely moves beyond visual inspection. In August 2008, a tractor-trailer fatally departed William Preston Lane, Jr. Memorial Bridge after it dislodged a section of the bridge barrier. Investigations following the accident identified significant corrosion of the anchor bolts attaching the bridge railing to the bridge deck. As a result of the information gathered during its investigation of the accident, the National Transportation Safety Board (NTSB) made recommendations to the Federal Highway Administration concerning Non-Destructive Evaluation (NDE) of concrete bridge railings. The Center for nondestructive evaluation (NDE) at Turner Fairbank Highway Research Center in McLean, VA is currently evaluating feasibility of using four technologies - ground penetrating radar (GPR), ultrasonic pulse-echo, digital radiography and infrared thermal imaging methods to develop bridge inspection methods that augment visual inspections, offer reliable measurement techniques, and are practical, both in terms of time and cost, for field inspection work. Controlled samples containing predefined corrosion levels in reinforcing steel were embedded at barrier connection points for laboratory testing. All four NDE techniques were used in the initial phase I testing. An inspection protocol for detecting and measuring the corrosion of reinforced steel embedded in the anchorage system will be developed as part of phase II research. The identified technologies shall be further developed for field testing utilizing a structure with a barrier in good condition and a structure with a barrier in poor condition.

  1. Orthodontic retreatment using anchorage with miniplate to camouflage a Class III skeletal pattern

    Directory of Open Access Journals (Sweden)

    Marcel Marchiori Farret

    Full Text Available ABSTRACT This manuscript describes the treatment of a 27-year-old patient who was previously treated with two maxillary first premolar extractions. The patient had skeletal Class III malocclusion, Class III canine relationship, anterior crossbite, and a concave profile. As the patient refused orthognathic surgery, a miniplate was used on the right side of the lower arch as an anchorage unit after the extraction of mandibular first premolars, aiding the retraction of anterior teeth. At the end of treatment, anterior crossbite was corrected, in which first molars and canines were in a Class I relationship, and an excellent intercuspation was reached. Furthermore, patient's profile remarkably improved as a result of mandibular incisor retraction. A 30-month follow-up showed good stability of the results obtained. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO as one of the requirements to become diplomate by the BBO.

  2. Elmendorf AFB, Anchorage, Alaska. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F

    Science.gov (United States)

    1979-09-17

    OBSERVATIONS) 260 EjJMENDORF AF0 ALASK /ANCHORAGE 6 6-79 SE ITATION STATION RAMP VEA~sS 505Thm CALL WIATivg 2800-2000 CLA" 40 isA IS EL..) ( CONDItION SPEED) 1...iiiiiiii - - _ l-l nA T A ,1, 1C. is Z’I e(’ ,It .,. - DAILY TEMPERATURES l if ?,52 4C: I L;I1.,-JuIqkI AF, ALA.aVA/Al C1-I!R1t .; ,| ’,i 5 -/ iSA ,;O...2 0. O 3,861.7 .550 8/5 . 1 1 2 14 101 Element (X) ZX9 Z X I Mean No. of Hours w th Temp rtu re < RJh 4418271 60855 69.9 87 870 . F 󈧤F 67F 73F 80F

  3. Orthodontic retreatment using anchorage with miniplate to camouflage a Class III skeletal pattern

    Science.gov (United States)

    Farret, Marcel Marchiori

    2016-01-01

    ABSTRACT This manuscript describes the treatment of a 27-year-old patient who was previously treated with two maxillary first premolar extractions. The patient had skeletal Class III malocclusion, Class III canine relationship, anterior crossbite, and a concave profile. As the patient refused orthognathic surgery, a miniplate was used on the right side of the lower arch as an anchorage unit after the extraction of mandibular first premolars, aiding the retraction of anterior teeth. At the end of treatment, anterior crossbite was corrected, in which first molars and canines were in a Class I relationship, and an excellent intercuspation was reached. Furthermore, patient's profile remarkably improved as a result of mandibular incisor retraction. A 30-month follow-up showed good stability of the results obtained. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as one of the requirements to become diplomate by the BBO. PMID:27409659

  4. The aesthetic composite bridge.

    Science.gov (United States)

    Feinman, R A

    1997-01-01

    New developments are constantly introduced in the search for the optimal treatment modality to restore a single anterior tooth. The patient attention has shifted to aesthetics of the restoration, biocompatibility of the dental materials utilized, conservative preparation of the teeth to be restored, and the retention of intact adjacent dentition. The learning objective of this article is to review the methods currently utilized and to present a recently introduced treatment modality--the two-component bridge, which combines the strength and resiliency of composite resin with the aesthetic advantages of porcelain. The technology of the material is reviewed, the predominantly lingual tooth preparation procedures are outlined, and the bridge try-in is described. The advantages of the two-component bridge are presented along with the contraindications and suggestions of careful case selection. Three cases with congenitally missing maxillary lateral incisors in youthful patients are presented to supplement the theoretical outline and to describe and illustrate the clinical procedure.

  5. Istanbul Bridge Conference 2014

    CERN Document Server

    Gülkan, Polat; Mahmoud, Khaled

    2016-01-01

      The book includes peer-reviewed contributions selected from presentations given at the Istanbul Bridge Conference 2014, held from August 11 – 13 in Istanbul, Turkey. It reports on the current challenges in bridge engineering faced by professionals around the globe, giving a special emphasis to recently developed techniques, innovations and opportunities. The book covers key topics in the field, including modeling and analysis methods; construction and erection techniques; design for extreme events and condition assessment and structural health monitoring. There is a balanced presentation of theory, research and practice. This book, which provides the readers with a comprehensive and timely reference guide on current practices in bridge engineering, is intended for professionals, academic researchers and students alike.

  6. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  7. BUILDING "BRIDGES" WITH QUALITY ASSURANCE

    Science.gov (United States)

    The papr describes how, rather than building "bridges" across centuries, quality assurance (QA) personnel have the opportunity to build bridges across technical disciplines, between public and private organizations, and between different QA groups. As reviewers and auditors of a...

  8. Existing Steel Railway Bridges Evaluation

    Science.gov (United States)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  9. DOE Information Bridge

    CERN Document Server

    United States. Department of Energy. Office of Scientific and Technical Information

    DOE Information Bridge, a component of EnergyFiles, provides free, convenient, and quick access to full-text DOE research and development reports in physics, chemistry, materials, biology, environmental sciences, energy technologies, engineering, computer and information science, renewable energy, and other topics. This vast collection includes over 43,000 reports that have been received and processed by OSTI since January 1995.

  10. Bridging the Technological Gap.

    Science.gov (United States)

    Lazow, Robert; And Others

    The aim of "Bridging the Technological Gap" (BTG), a federally funded demonstration project, is to use microcomputer technology in the rehabilitation of the psychiatrically disabled. Through the use of a custom designed microcomputer software package, clients receive remediation in areas of specific cognitive and behavioral deficits. The project…

  11. Bridging a Cultural Gap

    Science.gov (United States)

    Leviatan, Talma

    2008-01-01

    There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes--aimed at bridging the gap between high-school mathematics and tertiary mathematics--is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a…

  12. Bridge over troubled water?

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Nannestad, Peter; Svendsen, Gert Tinggaard

    2008-01-01

    The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...

  13. Building a Straw Bridge

    Science.gov (United States)

    Teaching Science, 2015

    2015-01-01

    This project is for a team of students (groups of two or three are ideal) to design and construct a model of a single-span bridge, using plastic drinking straws as the building material. All steps of the design, construction, testing and critiquing stages should be recorded by students in a journal. Students may like to include labelled diagrams,…

  14. Building Bridges to China.

    Science.gov (United States)

    Wasta, Stephanie; Scott, Margaret

    1998-01-01

    Describes a theme cycle called "Building Bridges to China" developed for third grade students that focuses on the similarities between the lives of children and families in China and the United States. Explains that the theme cycle addresses the National Geography Standards and three of the National Council for the Social Studies standards. (CMK)

  15. The Bridges of Taishun County

    Institute of Scientific and Technical Information of China (English)

    MaJianhe

    2003-01-01

    The American film The Bridges of Madison County captured the imagination of many Chinese moviegoers with its bittersweet love story and scenes of rustic covered bridges. But the U.S. can't lay sole claim to such spectacular rural sights:China has its own county worldrenowned for unforgettable bridges.

  16. Revised Rules for Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Jensen, F. M.; Middleton, C.;

    This paper is based on research performed for the Highway Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: Concrete Bridges" It contains details of a methodology which can be used to generate Whole Life (WL) reliability profiles....... These WL reliability profiles may be used to establish revised rules for Concrete Bridges....

  17. Dynamic Bridge Response for a Bridge-friendly Truck

    Directory of Open Access Journals (Sweden)

    V. Šmilauer

    2004-01-01

    Full Text Available A truck with controlled semi-active suspensions traversing a bridge is examined for benefits to the bridge structure. The original concept of a road-friendly truck was extended to a bridge-friendly vehicle, using the same optimization tools. A half-car model with two independently driven axles is coupled with simply supported bridges (beam, slab model with the span range from 5 m to 50 m. Surface profile of the bridge deck is either stochastic or in the shape of a bump or a pot in the mid-span. Numerical integration in the MATLAB/SIMULINK environment solves coupled dynamic equations of motion with optimized truck suspensions. The rear axle generates the prevailing load and to a great extent determines the bridge response. A significant decrease in contact road-tire forces is observed and the mid-span bridge deflections are on average smaller, when compared to commercial passive suspensions. 

  18. Bio-cultural anchorage of the prickly pear cactus in Tlalnepantla (Morelos, Mexico

    Directory of Open Access Journals (Sweden)

    Torres-Salcido, Gerardo

    2016-06-01

    Full Text Available The prickly pear cactus is a source of food with strong bio-cultural anchorage in Mexico. This is due to at least three factors: 1 the nature and heritage of cacti; 2 cultural heritage; and 3 the socio-cultural relationships with historical and symbolic roots that have facilitated knowledge of how to cultivate it and how to use it. The aim of this article is to put factors of territorial anchorage and its historical transformation in context by examining the case of the municipality of Tlalnepantla in the state of Morelos, Mexico. This community has experienced accelerated change due to the exchange of traditional crops for the prickly pear cactus and the integration of farming, commercialization and agro-transformation. Our hypothesis is that the market, internal conflicts and a lack of socio-institutional coordination have put social organization into crisis, favoring the territorial spread of the prickly pear cactus and making the Local Agro-Food Systems (LAFS of Tlalnepantla less competitive. The conclusions highlight important economic and social advances whose roots lie in the strengthening and anchorage of the territory-product. However, circumstances both internal and external to the community persist, such as intra-community conflicts, the international market and cultural paradigm shifts that affect the producers and put consolidation of the LAFS at risk.El nopal es un alimento con un fuerte anclaje bio-cultural en México, propiciado por al menos tres factores: 1 la naturaleza y el patrimonio de cactáceas; 2 el patrimonio cultural; y, 3 las relaciones socio-culturales que han permitido un “saber hacer” y un “saber utilizar” con raíces históricas y simbólicas. El objetivo es situar los factores de anclaje territorial y su transformación histórica tomando como caso el municipio de Tlalnepantla, en el estado de Morelos, México. Esta comunidad ha experimentado un acelerado cambio por la reconversión de los cultivos

  19. Simulation of multivariate diffusion bridges

    DEFF Research Database (Denmark)

    Bladt, Mogens; Finch, Samuel; Sørensen, Michael

    We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental role in simulation-based likelihood and Bayesian inference for stochastic differential equations. By a novel application of classical coupling methods, the new approach generalizes a previously...... proposed simulation method for one-dimensional bridges to the mulit-variate setting. First a method of simulating approzimate, but often very accurate, diffusion bridges is proposed. These approximate bridges are used as proposal for easily implementable MCMC algorithms that produce exact diffusion bridges...

  20. The U.S. Department of Energy Office of Indian Energy Policy and Programs, Anchorage, Alaska, Roundtable Summary

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-04-14

    The Anchorage, Alaska Roundtable on Tribal Energy Policy convened at 10:00 a.m., Thursday April 15th, at the downtown Anchorage Hilton. The meeting was held by the Department of Energy (DOE) Office of Indian Energy Policy and Programs (Office of Indian Energy). Tracey LeBeau, Director of the Office of Indian Energy, and Pilar Thomas, Deputy Director-Policy of the Office of Indian Energy, represented DOE. Approximately twenty-seven people attended the meeting, including representatives of three native Alaskan villages, four Alaskan tribal corporations representing more than 40 tribal governments, as well as representatives from tribal associations and conferences. Interested state, federal, and non-profit representatives also were present. A full list of attendees is at the end of this summary. The meeting was facilitated by the Udall Foundation’s U.S. Institute for Environmental Conflict Resolution (U.S. Institute).  

  1. Metallurgical Behavior of Ti-6Al-4V Alloy Mini-Implants as a Temporary Anchorage Device in Orthodontics Applications

    Directory of Open Access Journals (Sweden)

    Mendoza-Bravo Ivan

    2014-01-01

    Full Text Available The application of mini implants as a temporary anchorage device in orthodontics is a new technique that allows the movement of teeth in an efficient and predictable way. Although they have started to be used in Germany, Japan and South Korea, there is still the need to analyze and diffuse the advantages this procedure can offer over the traditional techniques. The objective of this research work was to analyze the integrity of Ti-6Al-4V mini implants temporary employed for 4 months on three patients as an anchorage device. The mini implants were analyzed by means of electron scanning microscopy in order to determine superficial and microstructural changes as well as the interaction with human tissue. Results showed the presence of wear on the thread zone caused during the insertion into the maxilar bone. The adherence of organic tissue was also observed on two mini-implants.

  2. Transdisciplinary treatment of Class III malocclusion using conventional implant-supported anchorage: 10-year posttreatment follow-up

    Directory of Open Access Journals (Sweden)

    Mariana Roennau Lemos Rinaldi

    2015-06-01

    Full Text Available INTRODUCTION: Combined treatment offers advantages for partially edentulous patients. Conventional implants, used as orthodontic anchorage, enable previous orthodontic movement, which provides appropriate space gain for crown insertion. OBJECTIVE: This case report describes the treatment of a 61-year and 10-month-old patient with negative overjet which made ideal prosthetic rehabilitation impossible, thereby hindering dental and facial esthetics. CASE REPORT: After a diagnostic setup, conventional implants were placed in the upper arch to anchor intrusion and retract anterior teeth. Space gain for lateral incisors was achieved in the lower arch by means of an orthodontic appliance. CONCLUSIONS: Integrated planning combining Orthodontics and Implantology provided successful treatment by means of conventional implant-supported anchorage. The resulting occlusal relationship proved stable after 10 years.

  3. Latest Pleistocene advance and collapse of the Matanuska - Knik glacier system, Anchorage Lowland, southern Alaska

    Science.gov (United States)

    Kopczynski, Sarah E.; Kelley, Samuel E.; Lowell, Thomas V.; Evenson, Edward B.; Applegate, Patrick J.

    2017-01-01

    At the end of the last ice age, glacier systems worldwide underwent dramatic retreat. Here, we document the advance and retreat of a glacier system with adjacent marine- and land-based components during the latter part of the Termination. We utilize three lines of evidence: lithologic provenance, geomorphic mapping, and radiocarbon ages derived from lake cores to reconstruct glacier extent and timing of advance and retreat within our study area centered at N 61.50°, W 149.50°, just north of Anchorage, Alaska. Two glaciers, sourced in the Talkeetna and Chugach Mountains, flowed down the Matanuska and Knik Valleys forming a coalesced lobe that advanced onto the Anchorage Lowlands and terminated at Elmendorf Moraine. We use the presence of lithologies unique to the Matanuska catchment in glacial drift to delineate the paleoflow lines and to estimate the suture line of the two glacier systems. The eastern side of the lobe, attributed to ice flow from the Knik Valley, was in contact with elevated marine waters within the Knik Arm fjord, and thus retreat was likely dominated by calving. Geomorphic evidence suggests the western side of the lobe, attributed to ice flow from Matanuska Valley, retreated due to stagnation. We constrain retreat of the combined Matanuska and Knik lobe with thirteen new radiocarbon ages, in addition to previously published radiocarbon ages, and with geomorphic evidence suggesting the retreat occurred in two phases. Retreat from the Elmendorf Moraine began between 16.8 and 16.4 ka BP. A second, faster retreat phase occurred later and was completed by 13.7 ka BP. With the 140 km of total retreat occurring over ∼3000 years or less. This pattern of glacial advance and retreats agrees well with the deglacial histories from the southern sectors of the Cordilleran Ice Sheet, as well as many other alpine glacier systems in the western U.S. and northern Alaska. This consistent behavior of glacier systems may indicate that climate oscillated over

  4. Are temporary anchorage devices truly effective in the treatment of skeletal open bites?

    Science.gov (United States)

    Turkkahraman, Hakan; Sarioglu, Mehmet

    2016-01-01

    Objective: The aims of this study were to evaluate the effects of temporary anchorage devices (TADs) in the treatment of skeletal open bites and to compare the results with untreated controls. Materials and Methods: A total of forty patients with skeletal anterior open bites were assigned to two groups of twenty each. The mean chronological age for the treatment group (14 female, 6 male) was 16.68 ± 2.80 years old, compared with 16.63 ± 2.83 years old for the control group (11 female, 9 male). Titanium miniplates fixed bilaterally to the infrazygomatic crest area were used as TADs and intrusive forces were applied to the posterior teeth with Ni-Ti coil springs. The treatment and normal growth changes were evaluated using 24 measurements (2 angular, 22 linear). Results: Statistically significant differences were found between the groups in Bx, By, Sn/GoGn, Ax-Bx, U6x, U6y, overjet, overbite, SN/OccP, N-Me, Ans-Me, S-Go/N-Me, interpremolar width, and intermolar width (P < 0.05). In the treatment group, statistically significant upper molar intrusion (mean ± standard deviation [SD], 3.59 ± 1.34; 95% confidence interval [CI], 2.96–4.22), posterior rotation of the occlusal plane (mean ± SD, 3.42 ± 2.17; 95% CI, 2.39–4.43), anterior rotation of the mandible (mean ± SD, 2.25 ± 1.91; 95% CI, 1.36–3.14), and resultant overbite improvement (mean ± SD, 4.82 ± 1.53; 95% CI, 4.10–5.53) were found (P < 0.05). Conclusions: Mild to moderate skeletal anterior open bites could easily be treated with TADs without orthognathic surgery. With the rigid anchorage of miniplates, true molar intrusion of up to 4 mm was achieved. With molar intrusion, anterior rotation of the mandible and a significant reduction in anterior face height were determined. PMID:28042256

  5. ROCK1 and ROCK2 are required for non-small cell lung cancer anchorage-independent growth and invasion.

    Science.gov (United States)

    Vigil, Dominico; Kim, Tai Young; Plachco, Ana; Garton, Andrew J; Castaldo, Linda; Pachter, Jonathan A; Dong, Hanqing; Chen, Xin; Tokar, Brianna; Campbell, Sharon L; Der, Channing J

    2012-10-15

    Evidence is emerging that the closely related ROCK1 and ROCK2 serine/threonine kinases support the invasive and metastatic growth of a spectrum of human cancer types. Therefore, inhibitors of ROCK are under preclinical development. However, a key step in their development involves the identification of genetic biomarkers that will predict ROCK inhibitor antitumor activity. One identified mechanism for ROCK activation in cancer involves the loss of function of the DLC1 tumor suppressor gene, which encodes a GTPase activating protein (RhoGAP) for the RhoA and RhoC small GTPases. DLC-1 loss may lead to hyperactivation of RhoA/C and its downstream effectors, the ROCK kinases. We therefore determined whether loss of DLC-1 protein expression identifies non-small cell lung carcinoma (NSCLC) cell lines whose growth and invasion phenotypes are sensitive to ROCK inhibition. We identified and characterized a novel small molecule pharmacologic inhibitor of ROCK and additionally applied genetic approaches to impair ROCK1 and/or ROCK2 activity, and we determined that although NSCLC anchorage-dependent growth was ROCK-independent, both anchorage-independent growth and Matrigel invasion were ROCK-dependent. However, loss of DLC-1 expression did not correlate with ROCK activation or with OXA-06 sensitivity. Unexpectedly, suppression of ROCK1 or ROCK2 expression alone was sufficient to impair anchorage-independent growth, supporting their nonoverlapping roles in oncogenesis. Mechanistically, the block in anchorage-independent growth was associated with accumulation of cells in the G(0)-G(1) phase of the cell cycle, but not increased anoikis. We conclude that ROCK may be a useful therapeutic target for NSCLC.

  6. CD45/CD11b Positive Subsets of Adult Lung Anchorage-Independent Cells Harness Epithelial Stem Cells

    OpenAIRE

    2012-01-01

    Compensatory growth is mediated by multiple cell types that interact during organ repair. To elucidate the relationship between the stem/progenitor cells that proliferate or differentiate and the somatic cells of lung, we utilized a novel ex vivo pneumoexplant system. Applying this technique, we identified a sustained culture of repopulating adult progenitors in the form of free floating anchorage-independent cells (AICs). AICs did not express integrin proteins α5, β3, and β7, and constituted...

  7. Overexpressed EDIL3 predicts poor prognosis and promotes anchorage-independent tumor growth in human pancreatic cancer

    Science.gov (United States)

    Feng, Ming-Xuan; Wang, Ya-Hui; Yang, Xiao-Mei; He, Ping; Tian, Guang-Ang; Zhang, Xiao-Xin; Li, Qing; Cao, Xiao-Yan; Huo, Yan-Miao; Yang, Min-Wei; Fu, Xue-Liang; Li, Jiao; Liu, De-Jun; Dai, Miao; Wen, Shan-Yun; Gu, Jian-Ren; Hong, Jie; Hua, Rong; Zhang, Zhi-Gang; Sun, Yong-Wei

    2016-01-01

    Epidermal Growth Factor-like repeats and Discoidin I-Like Domains 3 (EDIL3), an extracellular matrix (ECM) protein associated with vascular morphogenesis and remodeling, is commonly upregulated in multiple types of human cancers and correlates with tumor progression. However, its expression pattern and underlying cellular functions in pancreatic ductal adenocarcinoma (PDAC) remain largely unexplored. In current study, we observed that expression of EDIL3 was significantly up-regulated in PDAC compared with normal controls in both cell lines and clinical specimens. In addition, elevated EDIL3 expression was positively correlated with patients’ TNM stage and T classification. Kaplan-Meier analysis indicated that high EDIL3 expression was significantly associated with shorter overall survival times in PDAC patients. Multivariate Cox regression analysis confirmed EDIL3 expression, age, lymph node metastasis and histological differentiation as independent prognostic factors in PDAC. Knockdown of EDIL3 showed no significant influence on cell viability, migration, invasion and starvation-induced apoptosis, but compromised anoikis resistance and anchorage independent tumor growth of PDAC cells. Meanwhile, treatment with recombinant EDIL3 protein markedly promoted anoikis resistance and anchorage independent tumor growth. Mechanistically, we demonstrated that altered protein expression of Bcl-2 family might contribute to the oncogenic activities of EDIL3. In conclusion, this study provides evidences that EDIL3 is a potential predictor and plays an important role in anchorage independent tumor growth of PDAC and EDIL3-related pathways might represent a novel therapeutic strategy for treatment of pancreatic cancer. PMID:26735172

  8. Bridging Classroom Language Ethnography

    OpenAIRE

    GRENFELL, MICHAEL JAMES

    2012-01-01

    PUBLISHED Paper #5: Bridging Classroom Language Ethnography, New Literacy Studies and Bourdieu?s Social Philosophy: Principles and Practice The purpose of this paper is to analyze and synthesize the various ways that classroom language ethnography, NLS, and Bourdieu?s social philosophy, were integrated. The goal of the analysis and synthesis is to provide a fresh perspective and fruitful insights on literacy in all its manifestations that provides the foundations for a more robust...

  9. Bridging as Coercive Accommodation

    CERN Document Server

    Bos, J W; Mineur, A M; Bos, Johan; Buitelaar, Paul; Mineur, Anne-Marie

    1995-01-01

    In this paper we discuss the notion of "bridging" in Discourse Representation Theory as a tool to account for discourse referents that have only been established implicitly, through the lexical semantics of other referents. In doing so, we use ideas from Generative Lexicon theory, to introduce antecedents for anaphoric expressions that cannot be "linked" to a proper antecedent, but that do not need to be "accommodated" because they have some connection to the network of discourse referents that is already established.

  10. PAX2 regulates ADAM10 expression and mediates anchorage-independent cell growth of melanoma cells.

    Directory of Open Access Journals (Sweden)

    Sophia Boyoung Lee

    Full Text Available PAX transcription factors play an important role during development and carcinogenesis. In this study, we investigated PAX2 protein levels in melanocytes and melanoma cells by Western Blot and immunofluorescence analysis and characterized the role of PAX2 in the pathogenesis of melanoma. In vitro we found weak PAX2 protein expression in keratinocytes and melanocytes. Compared to melanocytes increased PAX2 protein levels were detectable in melanoma cell lines. Interestingly, in tissue sections of melanoma patients nuclear PAX2 expression strongly correlated with nuclear atypia and the degree of prominent nucleoli, indicating an association of PAX2 with a more atypical cellular phenotype. In addition, with chromatin immunoprecipitation assay, PAX2 overexpression and PAX2 siRNA we present compelling evidence that PAX2 can regulate ADAM10 expression, a metalloproteinase known to play important roles in melanoma metastasis. In human tissue samples we found co-expression of PAX2 and ADAM10 in melanocytes of benign nevi and in melanoma cells of patients with malignant melanoma. Importantly, the downregulation of PAX2 by specific siRNA inhibited the anchorage independent cell growth and decreased the migratory and invasive capacity of melanoma cells. Furthermore, the downregulation of PAX2 abrogated the chemoresistance of melanoma cells against cisplatin, indicating that PAX2 expression mediates cell survival and plays important roles during melanoma progression.

  11. Microbeads and anchorage-dependent eukaryotic cells: the beginning of a new era in biotechnology.

    Science.gov (United States)

    Miller, A O; Menozzi, F D; Dubois, D

    1989-01-01

    Modern methods for the mass cultivation of anchorage-dependent mammalian cells started with the advent of microcarrier technology. Largely for reasons pertaining to their mode of preparation and ease of cultivation, 150-230 microns microbeads have been overwhelmingly adopted and the technology around them developed. To meet high biomass, macroporous microbeads have been developed. Also, the chemistry of the microsupport has been adapted in order to afford better protection of fragile cells to mechanical wear while simultaneously reorienting their differentiation towards the sought aims (production of cytokines, enzymes etc. ...). Future progress depends upon solutions being brought to problems inherent to this new technology (maintenance of steady state conditions of growth etc. ...) as well as to requirements arising from animal cell culture in general (biosensors, bioreactor's design etc. ...). Besides such technical implementations, biology at large is also expected to benefit from the advent of microcarriers in fields as diverse as the preparation of metaphasic chromosomes in bulk, toxicity testing, organ reconstitution following cell transplantation etc.

  12. The perception of pain following interdental microimplant treatment for skeletal anchorage: a retrospective study.

    Science.gov (United States)

    Chen, Chun-Ming; Chang, Chao-San; Tseng, Yu-Chuan; Hsu, Kun-Rong; Lee, Kun-Tsung; Lee, Huey-Er

    2011-01-01

    During orthodontic therapy, patients frequently complain about pain and discomfort, especially during insertion of fixed appliances. Skeletal anchorage using an interdental microimplant is a new concept in orthodontic treatment. The purpose of this study was to investigate differences and changes in the level of pain among patients in relation to orthodontic microimplant treatments. Forty microimplants were applied to the maxilla as skeletal anchors in the orthodontic treatment. The visual analog scale (VAS) was used to evaluate the patients' perception of pain during this new modality treatment. The premolar extraction VAS core was used as a baseline for the complete orthodontic procedure. The mean VAS score was 35.8 mm at 24 h after premolar extraction. The mean VAS score for insertion and removal of the microimplant 24 h after the operation was 12.3 and 7.8 mm, respectively. Three months after removal of the skeletal anchors, the VAS score had decreased to 3.2 mm and was the same as with the traditional orthodontic treatment. By using the repeated-measure general linear model (GLM), we found that the score 1 day after microimplant placement was significantly less than that 1 day after first premolar extraction or that 1 day after fixed appliance insertion. This result indicates that interdental microimplant did not generate any greater pain than other orthodontic procedures. Therefore, patients were willing to adopt the new orthodontic treatment.

  13. Liquid marbles for high-throughput biological screening of anchorage-dependent cells.

    Science.gov (United States)

    Oliveira, Nuno M; Correia, Clara R; Reis, Rui L; Mano, João F

    2015-01-28

    Stable liquid marbles (LM) are produced by coating liquid droplets with a hydrophobic powder. The used hydrophobic powder is produced by fluorosi-lanization of diatomaceous earth, used before to produce superhydrophobic structures. Here, the use of LM is proposed for high-throughput drug screening on anchorage-dependent cells. To provide the required cell adhesion sites inside the liquid environment of LM, surface-modified poly(l-lactic acid) microparticles are used. A simple method that takes advantage from LM appealing features is presented, such as the ability to inject liquid on LM without disrupting (self-healing ability), and to monitor color changes inside of LM. After promoting cell adhesion, a cytotoxic screening test is performed as a proof of concept. Fe(3+) is used as a model cytotoxic agent and is injected on LM. After incubation, AlamarBlue reagent is injected and used to assess the presence of viable cells, by monitoring color change from blue to red. Color intensity is measured by image processing and the analysis of pictures takes using an ordinary digital camera. The proposed method is fully validated in counterpoint to an MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carbo​xymethoxyphenyl)-2-(4-sulfophenyl)-2H-te​trazolium) colorimetric assay, a well-known method used for the cytotoxicity assessment.

  14. Biomechanical comparison of four different miniscrew types for skeletal anchorage in the mandibulo-maxillary area.

    Science.gov (United States)

    Mischkowski, R A; Kneuertz, P; Florvaag, B; Lazar, F; Koebke, J; Zöller, J E

    2008-10-01

    This study compared four miniscrew types for skeletal anchorage (Aarhus, FAMI, Dual Top and Spider) regarding their biomechanical properties contributing to primary stability. Insertion torque measurements and pull-out tests in axial (0 degrees ) as well as in the 20 degrees and 40 degrees direction were performed. Stiffness of the screw-bone construct was calculated from the load-displacement curve. Conic FAMI and Dual Top screws had higher insertion torques. Insertion torques were raised by drill-free insertion of FAMI and Dual Top screws. Statistically significant differences were found between the 4 screw types in pull-out tests. The highly significant differences between the four screws for peak load in the axial (0 degrees ) and 20 degrees direction were not apparent in 40 degrees angular loads. For the conical screws, peak load values increased in angular compared with axial load. The Dual Top screw achieved the highest values for peak load and stiffness. 12 Dual Top and 1 Spider screw heads fractured in the pull-out tests. A conical drill-free screw design achieves higher primary stability compared with cylindrical self-tapping screws. This effect was more obvious in insertion torque estimations rather than in pull-out tests. The Dual Top screws, although biomechanically superior to other screw types, were most prone to fractures.

  15. Parametrically excited oscillation of stay cable and its control in cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    孙炳楠; 汪至刚; 高赞明; 倪一清

    2003-01-01

    This paper presents a nonlinear dynamic model for simulation and analysis of a kind of parametrically excited vibration of stay cable caused by support motion in cable-stayed bridges. The sag, inclination angle of the stay cable are considered in the model, based on which, the oscillation mechanism and dynamic response characteristics of this kind of vibration are analyzed through numerical calculation. It is noted that parametrically excited oscillation of a stay cable with certain sag, inclination angle and initial static tension force may occur in cable-stayed bridges due to deck vibration under the condition that the natural frequency of a cable approaches to about half of the first model frequency of the bridge deck system. A new vibration control system installed on the cable anchorage is proposed as a possible damping system to suppress the cable parametric oscillation. The numerical calculation results showed that with the use of this damping system, the cable oscillation due to the vibration of the deck and/or towers will be considerably reduced.

  16. Vulnerability of bridges to fire

    DEFF Research Database (Denmark)

    Giuliani, Luisa; Crosti, C.; Gentili, F.

    2012-01-01

    Even if recent effort in developing methodology and measures for design structures against fire and explosions has been mostly focused on buildings, bridges can also be very sensitive to those actions, as witnesses by some recent bridge accidents, which caused major economic losses and also...... endangered people safety in few cases. Purpose of this paper is making a focus on the state of the art of the research and current regulations concerning the response of bridges to fire. Several cases of bridge fires are reported and a focus is made on the occurrence and consequence of bridge fires......, considering both the costs deriving by structural damages and by limited serviceability and other indirect societal aspects. Few cases of recent bridge fire are reviewed in detail and structural consequences are highlighted, distinguishing between damages directly induced by fire and damages induced by local...

  17. Morphological aspects of myocardial bridges.

    Science.gov (United States)

    Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

    2013-11-01

    Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  18. Modular FRP Composite Bridge Deck

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    The bridge infrastructure of the United States is in constant need of repair and rehabilitation. It is reported that 43% of the bridges in the USA have been identified as being structurally deficient or functionally obsolete due to corrosion. SuperdeckTM, a non-corrosive fiber reinforced polymer (FRP) composite bridge deck. The Deck is designed and engineered into a lightweight, strong and rigid structure that will not corrode. The deck sections, composed of hexagon and double-trapezoid profi...

  19. Research Progress of the Anchorage Control in Orthodontic Treatment%正畸治疗中支抗控制的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘春利; 肖丹娜

    2015-01-01

    The anchorage control is very important in orthodontic treatment,and good design matters to the success or failure of the treatment.Anchorage control includes two aspects of anchorage strengthening and anchorage saving,which both should be taken into consideration,and joint applied in the process of treat-ment.Effect of orthodontic treatment needs multidimensional performance evaluation,to achieve high quality of treatment,sagittal,vertical,and horizontal control should be done according to patients'vertical bone sur-face type and the type of teeth micromaxillary deformity.Here is to make a review of the common methods to strengthen the anchorage,as well as the emerging of strengthening anchorage design,and the idea of the anchorage saving,and the choices of operational and correctional systems.%正畸治疗中支抗控制至关重要,合理的支抗设计关系到治疗的成败。支抗控制可从支抗加强和支抗节省两方面考虑,并在治疗过程中联合应用。正畸治疗效果需以多维效果评价,为取得优质的治疗效果支抗需根据患者的垂直骨面型、牙颌畸形的类型,在矢状向、垂直向、水平向进行控制。该文就目前常用的加强支抗的方法进行简要概括,同时对新兴加强支抗的设计进行简要总结,并对支抗节省的理念、操作和矫治系统的选择进行综述。

  20. Modelling railway bridge asset management

    OpenAIRE

    Le, Bryant Linh Hai

    2014-01-01

    The UK has a long history in the railway industry with a large number of railway assets. Railway bridges form one of the major asset groups with more than 35,000 bridges. The majority of the bridge population are old being constructed over 100 years ago. Many of the bridges were not designed to meet the current network demand. With an expected increasing rate of deterioration due to the increasing traffic loads and intensities, the management authorities are faced with the difficult task of k...

  1. A temporal study of urban development for the municipality of Anchorage, Alaska

    Science.gov (United States)

    Markon, Carl J.

    2003-01-01

    A land use/land cover database was produced for a portion of the Municipality of Anchorage, Alaska to document the temporal and spatial extent of urbanization to assist in the analysis of changes in impervious cover and water quality. Data were derived from black and white and color infrared aerial photography, and satellite imagery from the early 1970's to 2000 in roughly ten‐year increments. Aerial photographs and satellite data were manually interpreted to identify and map land use/land cover classes which were then entered into a geographic information system, attributed, and georeferenced to a U.S. Geological Survey topographic map base. The spatial extent of the study was 31,117 hectares. In the early 1970's, approximately 7,356 hectares (24%) of the study area were mapped as urban developed. During the 30‐year analysis period, the largest increase in urban development occurred between the late 1970's and early 1980's when urban area increased to 12,263 hectares (39%). Between 1980 and 1990, and 1990 and 2000, urban area increased to 12,762 hectares (41%), and 13,980 hectares (45%) respectively. Most development occurred in forested or tall shrub areas, although some also occurred in wetlands. Between 1970 and 2000, close to 1,300 hectares of wetlands were lost due to development. Contrary to this, the amount of lake and pond area increased slightly from 261 hectares in 1973 to 334 hectares in 1980, and reduced to 310 hectares by 2000. The increase was primarily due to the filling in of gravel pits with spring melt water.

  2. Nitrate source indicators in ground water of the Scimitar Subdivision, Peters Creek area, Anchorage, Alaska

    Science.gov (United States)

    Wang, Bronwen; Strelakos, Pat M.; Jokela, Brett

    2000-01-01

    A combination of aqueous chemistry, isotopic measurement, and in situ tracers were used to study the possible nitrate sources, the factors contributing to the spatial distribution of nitrate, and possible septic system influence in the ground water in the Scimitar Subdivision, Municipality of Anchorage, Alaska. Two water types were distinguished on the basis of the major ion chemistry: (1) a calcium sodium carbonate water, which was associated with isotopically heavier boron and with chlorofluorocarbons (CFC's) that were in the range expected from equilibration with the atmosphere (group A water) and (2) a calcium magnesium carbonate water, which was associated with elevated nitrate, chloride, and magnesium concentrations, generally isotopically lighter boron, and CFC's concentrations that were generally in excess of that expected from equilibration with the atmosphere (group B water). Water from wells in group B had nitrate concentrations that were greater than 3 milligrams per liter, whereas those in group A had nitrate concentrations of 0.2 milligram per liter or less. Nitrate does not appear to be undergoing extensive transformation in the ground-water system and behaves as a conservative ion. The major ion chemistry trends and the presence of CFC's in excess of an atmospheric source for group B wells are consistent with waste-water influences. The spatial distribution of the nitrate among wells is likely due to the magnitude of this influence on any given well. Using an expanded data set composed of 16 wells sampled only for nitrate concentration, a significant difference in the static water level relative to bedrock was found. Well water samples with less than 1 milligram per liter nitrate had static water levels within the bedrock, whereas those samples with greater than 1 milligram per liter nitrate had static water levels near or above the top of the bedrock. This observation would be consistent with a conceptual model of a low-nitrate fractured bedrock

  3. Recorded earthquake responses from the integrated seismic monitoring network of the Atwood Building, Anchorage, Alaska

    Science.gov (United States)

    Celebi, M.

    2006-01-01

    An integrated seismic monitoring system with a total of 53 channels of accelerometers is now operating in and at the nearby free-field site of the 20-story steel-framed Atwood Building in highly seismic Anchorage, Alaska. The building has a single-story basement and a reinforced concrete foundation without piles. The monitoring system comprises a 32-channel structural array and a 21-channel site array. Accelerometers are deployed on 10 levels of the building to assess translational, torsional, and rocking motions, interstory drift (displacement) between selected pairs of adjacent floors, and average drift between floors. The site array, located approximately a city block from the building, comprises seven triaxial accelerometers, one at the surface and six in boreholes ranging in depths from 15 to 200 feet (???5-60 meters). The arrays have already recorded low-amplitude shaking responses of the building and the site caused by numerous earthquakes at distances ranging from tens to a couple of hundred kilometers. Data from an earthquake that occurred 186 km away traces the propagation of waves from the deepest borehole to the roof of the building in approximately 0.5 seconds. Fundamental structural frequencies [0.58 Hz (NS) and 0.47 Hz (EW)], low damping percentages (2-4%), mode coupling, and beating effects are identified. The fundamental site frequency at approximately 1.5 Hz is close to the second modal frequencies (1.83 Hz NS and 1.43 EW) of the building, which may cause resonance of the building. Additional earthquakes prove repeatability of these characteristics; however, stronger shaking may alter these conclusions. ?? 2006, Earthquake Engineering Research Institute.

  4. Tongue resting pressure of the tongue anchorage pad in different body positions: a pilot study.

    Science.gov (United States)

    Zeng, J; Xu, K; Gao, X; Xu, T

    2015-06-01

    We designed a modified transpalatal arch (tongue anchorage pad, TAP) to help control the vertical dimension. This study aimed to evaluate its efficiency by measuring the tongue resting pressure at different anteroposterior positions of the TAP in the upright and supine positions and to investigate the effect of changes in body position. Our study recruited 17 volunteers with individual normal occlusion (4 males, 13 females, age 22-33 years). An individualised TAP was designed for each subject. With a miniature sensor (FSS1500NS) installed in the device, we measured the pressure at the level of the distal second premolar (PM2), the first molar (M1) and the second molar (M2) in both the upright and supine positions. Nonparametric analysis was applied with the level of significance set at 0.05. In the upright position, tongue pressures obtained at PM2, M1 and M2 were 183.94, 130.81 and 113.07 Pa, respectively, with the maximum value detected at PM2 (P = 0.001). While in the supine position, pressures of 187.03, 156.87 and 201.69 Pa were detected at the same sites, with significantly higher values for M1 (P = 0.002) and M2 (P = 0.004). Tongue resting pressure decreases from the anterior aspect to the posterior aspect in the upright position. In the supine position, the pressure is consistent across the midline with pressure enhancement at M1 and M2. As many questions remain about this appliance and appropriate intruding force, further clinical and basic studies are required prior to its clinical implementation.

  5. Anchorage of mature conifers: resistive turning moment, root-soil plate geometry and root growth orientation.

    Science.gov (United States)

    Lundström, Tor; Jonas, Tobias; Stöckli, Veronika; Ammann, Walter

    2007-09-01

    Eighty-four mature Norway spruce (Picea abies L. Karst), silver fir (Abies alba Mill) and Scots pine (Pinus sylvestris L.) trees were winched over to determine the maximum resistive turning moment (M(a)) of the root-soil system, the root-soil plate geometry, the azimuthal orientation of root growth, and the occurrence of root rot. The calculation of M(a), based on digital image tracking of stem deflection, accounted not only for the force application and its changing geometry, but also for the weight of the overhanging tree, representing up to 42% of M(a). Root rot reduced M(a) significantly and was detected in 25% of the Norway spruce and 5% of the silver fir trees. Excluding trees with root rot, differences in M(a) between species were small and insignificant. About 75% of the variance in M(a) could be explained by one of the four variables--tree mass, stem mass, stem diameter at breast height squared times tree height, and stem diameter at breast height squared. Among the seven allometric variables assessed above ground, stem diameter at breast height best described the root-soil plate dimensions, but the correlations were weak and the differences between species were insignificant. The shape of the root-soil plate was well described by a depth-dependent taper model with an elliptical cross section. Roots displayed a preferred azimuthal orientation of growth in the axis of prevailing winds, and the direction of frequent weak winds matched the orientation of growth better than that of rare strong winds. The lack of difference in anchorage parameters among species probably reflects the similar belowground growth conditions of the mature trees.

  6. Preliminary assessment report for Camp Carroll Training Center, Installation 02045, Anchorage, Alaska. Installation Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Krokosz, M.; Sefano, J.

    1993-08-01

    This report presents the results of the preliminary assessment (PA) conducted by Argonne National Laboratory at the Alaska Army National Guard property known as Camp Carroll Training Center, located on the Fort Richardson Army facility near Anchorage, Alaska. Preliminary assessments of federal facilities are being conducted to compile the information necessary for the completion of preremedial activities and to provide a basis for establishing, corrective actions in response to releases of hazardous substances. The principal objective of the PA is to characterize the site accurately and determine the need for further action by examining site activities, types and quantities of hazardous substances used, the nature and amounts of wastes generated or stored at the facility, and potential pathways by which contamination could affect public health and the environment. The primary environmentally significant operations (ESOs) associated with the property are (1) the Alaska Air National Guard storage area behind Building S57112 (Organizational Maintenance Shop [OMS] 6); (2) the state of Alaska maintenance facility and the soil/tar-type spill north of the state of Alaska maintenance facility; (3) the waste storage area adjacent to OMS 6; (4) the contaminated area from leaking underground storage tanks (USTs) and the oil-water separator; and (5) soil staining in the parking area at the Camp Carroll Headquarters Building. Camp Carroll appears to be in excellent condition from an environmental standpoint, and current practices are satisfactory. Argonne recommends that the Alaska Department of Military Affairs consider remediation of soil contamination associated with all storage areas, as well as reviewing the practices of other residents of the facility. Argonne also recommends that the current methods of storing waste material behind Building S57112 (OMS 6) be reviewed for alternatives.

  7. Optimization Design of Anchorage Structure for Safety Belt on Rear Floor%后地板安全带固定点结构优化设计

    Institute of Scientific and Technical Information of China (English)

    闻培培; 李宏华; 赵福全

    2012-01-01

    针对后地板安全带固定点的3种结构形式,对后地板安全带固定点相关法规进行了介绍,并对后排安全带固定点的强度进行了分析.通过分析某车型后地板安全带固定点强度失效原因,对其后地板安全带固定点结构和焊点进行了优化,优化后的结构在模具冲压和车身焊接中均未出现问题,满足了静拉试验相关法规要求.%The three structural types of anchorage point of safety belt on rear floor and the regulations of anchorage point of rear safety belts are introduced in this paper, and the strength of rear seat belt anchorage point is analyzed. By analyzing cause of failure of seat belt anchorage of rear floor of a vehicle model, optimization is made to seat belt anchorage structure and welding point of its rear floor, the optimized structure does not fail either in die stamping nor body welding, and related regulation requirement of static tensile test is thus satisfied.

  8. Design of Cable-Stayed Bridge of Caofeidian Industry Zone Bridge No.1%曹妃甸工业区1号桥斜拉桥设计

    Institute of Scientific and Technical Information of China (English)

    陈亮; 卢永成; 周伟翔; 邵长宇

    2011-01-01

    The Caofeidian Industry Zone Bridge No. 1 is composed of navigable span bridge, non-navigable span bridges and approach bridges and is located in the cold and strong earthquake region in the northern part of China. A summarized account of the design of the navigable span bridge of the bridge is presented herewith. In accordance with the construction conditions and landscape requirements, the navigable span bridge is designed as a single pylon and single cable plane cable-stayed bridge with span arrangement 2 X 138 m, the pylon is the column pylon in shape of boat sail. The anchorage zone in the pylon is the steel anchor box exposed outside the pylon. The main girder is the steel and concrete composite girder having three cells and a single box. The stay cables are made up of φ7 mm galvanized parallel steel wires and the foundation of the pylon pier is the group pile foundation. The research of seismic resistance of the bridge show that for a major single pylon cable-stayed bridge located in the strong earthquake region, the rigid fixity system of pylon, girder and pier should be possibly avoided in order to reduce seismic response of the bridge structure.%曹妃甸工业区1号桥位于北方寒冷强震区,由通航孔桥、非通航孔桥及引桥组成,综述该桥通航孔桥设计.根据建设条件及景观要求,通航孔桥为跨径2×138 m独塔单索面斜拉桥;桥塔为独柱形,造型为船帆式;索塔锚固区采用外露式钢锚箱方案;主梁采用单箱三室钢-混凝土箱形结合梁;斜拉索采用φ7 mm镀锌平行钢丝;桥塔墩采用群桩基础.抗震性能研究表明,强震区大型独塔斜拉桥应尽量避免采用塔、梁、墩固结体系,以减小桥梁结构的地震响应.

  9. London Bridge Is Shaking Funny

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Bridges generally don’t fall down without warning;they crack first. Searching for cracks is a tedious business,though, and bridge inspectors bave been known to miss them. Charles Farrar,a civil engineer at Los Alamos Na-

  10. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2004-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  11. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2005-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  12. Intrusão dentária utilizando mini-implantes Orthodontic intrusion with mini-implant anchorage

    Directory of Open Access Journals (Sweden)

    Telma Martins de Araújo

    2008-10-01

    Full Text Available INTRODUÇÃO: dentre os diversos tipos de movimentos dentários induzidos ortodonticamente, o de intrusão é, sem dúvida, um dos mais difíceis de serem conseguidos. A mecânica intrusiva convencional, apesar de viável, é complexa, no que diz respeito ao controle de seus efeitos colaterais. Isso, em grande parte, refere-se à dificuldade em se obter uma ancoragem satisfatória. Neste contexto, os mini-implantes, por oferecerem efetiva ancoragem esquelética, têm se mostrado de extrema valia para os ortodontistas, tornando a intrusão, tanto de dentes anteriores quanto posteriores, um procedimento cada vez mais simples, do ponto de vista mecânico. OBJETIVO: pretende-se, então, neste artigo, descrever e demonstrar, clinicamente, as diversas possibilidades de utilização dos mini-implantes como recurso de ancoragem para o movimento de intrusão.INTRODUCTION: Among all different varieties of orthodontically induced tooth movement, intrusion is, without doubt, one of the most difficult movements to be reached. Conventional intrusive biomechanics, although possible, may lead to undesirable side-effects. These events, in most cases, are related to the difficulty in obtaining an efficient anchorage unit. Then, mini-implants, because of their high success rates of effective skeletal anchorage, are valuable devices to orthodontists, transforming the intrusion movement, both at the anterior and the posterior regions, a more and more uncomplicated biomechanical procedure. AIM: to describe and show, clinically, different ways of using mini-implants as an anchorage system to intrusion movement.

  13. Abduction of Toe-excavation Induced Failure Process from LEM and FDM for a Dip Slope with Rock Anchorage in Taiwan

    Science.gov (United States)

    Huang, W.-S.; Lin, M.-L.; Liu, H.-C.; Lin, H.-H.

    2012-04-01

    On April 25, 2010, without rainfall and earthquake triggering a massive landslide (200000 m3) covered a 200m stretch of Taiwan's National Freeway No. 3, killing 4 people, burying three cars and destroying a bridge. The failure mode appears to be a dip-slope type failure occurred on a rock anchorage cut slope. The strike of Tertiary sedimentary strata is northeast-southwest and dip 15˚ toward southeast. Based on the investigations of Taiwan Geotechnical Society, there are three possible factors contributing to the failure mechanism as follow:(1) By toe-excavation during construction in 1998, the daylight of the sliding layer had induced the strength reduction in the sliding layer. It also caused the loadings of anchors increased rapidly and approached to their ultimate capacity; (2) Although the excavated area had stabilized soon with rock anchors and backfills, the weathering and groundwater infiltration caused the strength reduction of overlying rock mass; (3) The possible corrosion and age of the ground anchors deteriorate the loading capacity of rock anchors. Considering the strength of sliding layer had reduced from peak to residual strength which was caused by the disturbance of excavation, the limit equilibrium method (LEM) analysis was utilized in the back analysis at first. The results showed the stability condition of slope approached the critical state (F.S.≈1). The efficiency reduction of rock anchors and strength reduction of overlying stratum (sandstone) had been considered in following analysis. The results showed the unstable condition (F.S. <1). This research also utilized the result of laboratory test, geological strength index(GSI) and finite difference method (FDM, FLAC 5.0) to discuss the failure process with the interaction of disturbance of toe-excavation, weathering of rock mass, groundwater infiltration and efficiency reduction of rock anchors on the stability of slope. The analysis indicated that the incremental load of anchors have

  14. Development of cooperative system bridges

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; WAN Qi-bai; SHI Lei

    2008-01-01

    Cooperative system bridges comprise several basic structures that act jointly to improve structural characteristics. We delved into the historical development of cooperative system bridges. Cooperative systems are classified as different-load cooperative systems and same-load cooperative systems by distinguishing the modes of load distribution. For different-load cooperation, individual basic structures are at different positions in the direction along bridge axis and carry the loads separately. While for same-load cooperation, all basic structures overlap in geometrical locations and support the entire loads conjointly. The choosing of span ratios between basic structures, the design of connections of different-load cooperative systems were discussed as well as optimizations of relative rigidity for same-load cooperative systems which greatly influence structural characteristics. The general situation and several structural measurements of several cooperative bridges were demonstrated. This information can assist engineers in developing their concepts in cooperative systems and can lead to more efficient and economical cooperative bridges.

  15. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst......The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... groups, the sociology of work needs to develop a better understanding of the way in which linguistic diversity influences the formation of social capital, i.e. resources such as the trust and reciprocity inherent in social relations in such workplaces. Drawing on theories about intergroup contact...

  16. Looking Beyond the Bridge

    DEFF Research Database (Denmark)

    Jahn, Elke; Rosholm, Michael

    We perform a comprehensive analysis of the stepping-stone effect of temporary agency employment on unemployed workers. Using the timing-of-events approach, we not only investigate whether agency employment is a bridge into regular employment but also analyze its effect on post-unemployment wages ...... is even more effective in tight labor markets, where firms use agency employment primarily to screen po-tential candidates for permanent posts. Finally, our results suggest that agency employment may improve subsequent match quality in terms of wages and job duration....... and job stability for unemployed Danish workers. We find evidence of large positive treatment effects, particularly for immigrants. There is also some indication that higher treatment intensity increases the likelihood of leav-ing unemployment for regular jobs. Our results show that agency employment...

  17. Cascaded resonant bridge converters

    Science.gov (United States)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  18. Torsional instability in suspension bridges: The Tacoma Narrows Bridge case

    Science.gov (United States)

    Arioli, Gianni; Gazzola, Filippo

    2017-01-01

    All attempts of aeroelastic explanations for the torsional instability of suspension bridges have been somehow criticised and none of them is unanimously accepted by the scientific community. We suggest a new nonlinear model for a suspension bridge and we perform numerical experiments with the parameters corresponding to the collapsed Tacoma Narrows Bridge. We show that the thresholds of instability are in line with those observed the day of the collapse. Our analysis enables us to give a new explanation for the torsional instability, only based on the nonlinear behavior of the structure.

  19. Combined maxillary and mandibular midline and mandibular ramus distraction osteogenesis for treatment of a Class II patient with implants as orthodontic anchorage.

    Science.gov (United States)

    Takahashi, Ichiro; Kawamura, Hiroshi; Takano-Yamamoto, Teruko

    2010-03-01

    This case report describes the treatment of a woman with severe mandibular retrusion and maxillomandibular transverse deficiency. Her malocclusion was characterized by a large overjet, a deep overbite, and a V-shaped dental arch, and she had a skeletal Class II profile. Treatement included combined maxillary and mandibular midline expansion, maxillary downward repositioning, and mandibular ramus lengthening with distraction osteogenesis with implants as orthodontic anchorage. During the postdistraction orthodontic treatment period, some skeletal relapse occurred. Implants provided absolute orthodontic anchorage to overcome the unexpected skeletal changes. Combined orthodontic treatment with implants for anchorage and distraction osteogenesis successfully expanded the maxilla and the mandible and corrected the mandibular deficiency. Two-year follow-up records show a morphologically and functionally stable result.

  20. 种植体支抗在正畸临床上的应用%Implant Anchorage in Orthodontic Clinical Application

    Institute of Scientific and Technical Information of China (English)

    刘丽梅

    2015-01-01

    目的:探讨种植体支抗在正畸临床治疗。方法对20例种植体支抗的正畸治疗应用方法及临床应用体会。结果20例种植体支抗,微镙钉种植16例,钛板种植体3例,修复种植体1例。种植体均保持了稳定,种植体周围软组织健康,脱落率10%。结论牙齿的缺失造成支抗的不足,某些类型的牙齿移动难以或不能完成。将钛合金牙种植体作为支抗完成正畸治疗,正畸治疗结束后,将种植体行永久性修复。%Objective To investigate the implant anchorage in orthodontic clinical treatment. Methods 20 cases of implant anchorage orthodontic treatment application methods and clinical application experience. Results 20 cases of implant anchorage, micro screws planting 16 cases, 3 cases of titanium implants , implant restoration one case . Implants have maintained a stable implant soft tissue health, loss rate of 10%. Conclusion The lack of teeth caused by lack of anchorage, and certain types of tooth movement difficult or impossible to complete. The titanium dental implants as orthodontic anchorage is completed, after the end of orthodontic treatment, the implant permanently repair the line, traditional dental implant anchorage to be more widely used in orthodontic patients with a combination therapy of implant restoration.

  1. National Bridge Inventory - National Geospatial Data Asset (NGDA) Bridges

    Data.gov (United States)

    Department of Transportation — The NBI (NTAD 2015) is a collection of information (database) describing the more than 610,000 of the Nation's bridges located on public roads, including Interstate...

  2. Bridge Creek IMW database - Bridge Creek Restoration and Monitoring Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The incised and degraded habitat of Bridge Creek is thought to be limiting a population of ESA-listed steelhead (Oncorhynchus mykiss). A logical restoration approach...

  3. Bst1 is required for Candida albicans infecting host via facilitating cell wall anchorage of Glycosylphosphatidyl inositol anchored proteins

    Science.gov (United States)

    Liu, Wei; Zou, Zui; Huang, Xin; Shen, Hui; He, Li Juan; Chen, Si Min; Li, Li Ping; Yan, Lan; Zhang, Shi Qun; Zhang, Jun Dong; Xu, Zheng; Xu, Guo Tong; An, Mao Mao; Jiang, Yuan Ying

    2016-01-01

    Glycosylphosphatidyl inositol anchored proteins (GPI-APs) on fungal cell wall are essential for invasive infections. While the function of inositol deacylation of GPI-APs in mammalian cells has been previously characterized the impact of inositol deacylation in fungi and implications to host infection remains largely unexplored. Herein we describe our identification of BST1, an inositol deacylase of GPI-Aps in Candida albicans, was critical for GPI-APs cell wall attachment and host infection. BST1-deficient C. albicans (bst1Δ/Δ) was associated with severely impaired cell wall anchorage of GPI-APs and subsequen unmasked β-(1,3)-glucan. Consistent with the aberrant cell wall structures, bst1Δ/Δ strain did not display an invasive ability and could be recognized more efficiently by host immune systems. Moreover, BST1 null mutants or those expressing Bst1 variants did not display inositol deacylation activity and exhibited severely attenuated virulence and reduced organic colonization in a murine systemic candidiasis model. Thus, Bst1 can facilitate cell wall anchorage of GPI-APs in C. albicans by inositol deacylation, and is critical for host invasion and immune escape. PMID:27708385

  4. General design of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Xigang; Yuan Hong; Pei Minshan; Dai Jie; Xu Lin

    2009-01-01

    The main span of Sutong Bridge is a double-pylon, double-plane cable-stayed bridge with steel box girder, which has the world's longest central span of 1 088 m within cable-stayed bridges. To overcome problems caused by severe meteorological conditions, perplexing hydrological conditions, deep buried bedrock and higher navigation level, many new technics and methods were created. Keys including structural system, steel box girder, stayed cable, tower, pier, tower foundation, collision avoidance system, wind-resistance, seismic-resistance, structural nonlinear response and structural static stability were presented individually in this paper.

  5. Reliability Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Middleton, C. R.

    This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

  6. The Higgs Bridge

    CERN Document Server

    Allen, Roland E

    2013-01-01

    The particle recently discovered at the Large Hadron Collider near Geneva is almost certainly a Higgs boson, the long-sought completion of the Standard Model of particle physics. But this discovery, an achievement by more than six thousand scientists (including students), is actually much more than a mere capstone of the Standard Model. It instead represents a bridge from the Standard Model to exciting discoveries of the future, at higher energies or in other experiments, and to the properties of matter at very low temperatures. The mere existence of a particle with zero spin implies a need for new physics, with the most likely candidate being supersymmetry, which requires that every known particle has a superpartner yet to be discovered. And phenomena similar to the Higgs are seen in superconducting metals and superfluid gases at low temperatures, which extend down to a millionth or even a billionth of a degree Kelvin. So the discovery of a Higgs boson has a central place in our attempts both to achieve a tr...

  7. Mineral bridges in nacre revisited

    CERN Document Server

    Checa, Antonio G; Willinger, Marc-Georg

    2012-01-01

    We confirm with high-resolution techniques the existence of mineral bridges between superposed nacre tablets. In the towered nacre of both gastropods and the cephalopod Nautilus there are large bridges aligned along the tower axes, corresponding to gaps (150-200 nm) in the interlamellar membranes. Gaps are produced by the interaction of the nascent tablets with a surface membrane that covers the nacre compartment. In the terraced nacre of bivalves bridges associated with elongated gaps in the interlamellar membrane (> 100 nm) have mainly been found at or close to the edges of superposed parental tablets. To explain this placement, we hypothesize that the interlamellar membrane breaks due to differences in osmotic pressure across it when the interlamellar space below becomes reduced at an advanced stage of calcification. In no cases are the minor connections between superimposed tablets (< 60 nm), earlier reported to be mineral bridges, found to be such.

  8. The stories of two bridges in Ghana

    DEFF Research Database (Denmark)

    Andreasen, Jørgen

    2004-01-01

    Public participation in bridge building was promoted by un habitat in the village of Mankrong. The neighbouring village did not participate in the construction of their bridge. The first flooding washed the second bridge down while the "participative bridge" stood up....

  9. Redundancy Evaluation of Fracture Critical Bridges

    OpenAIRE

    Bapat, Amey Vivek

    2014-01-01

    Cases of brittle fractures in major bridges prompted AASHTO to publish its first fracture control plan in 1978. It focused on material and fabrication standards, and required periodic 24-month hands-on inspection of bridges with fracture critical members. The practical result of this plan was to significantly increase the life cycle cost of these bridges, rendering them uneconomical. Apart from the Point Pleasant Bridge that failed in 1967, no other bridge has collapsed in the USA following a...

  10. Environmental life cycle assessment comparison between two bridge types: reinforced concrete bridge and steel composite bridge

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2013-01-01

    not been integrated into the decision-making process. This paper presents a systematic LCA method for quantifying the environmental impacts for bridges. The comparison study is performed between a reinforced concrete bridge and a steel bridge as an alternative design, with several key maintenance and EOL...... scenarios outlined. LCA study is performed with the ReCiPe methodology with life cycle inventories data from public database. Five selected mid-point level impact categories and the energy consumption are presented. The result shows that the steel bridge has a better environmental performance due...... to the recycling strategy, while the initial material manufacture is the most dominant phase that contributes large environmental impact in both design solutions....

  11. Remains of the ancient ports and anchorage points at Miyani and Visawada, on the west coast of India: A study based on underwater investigations

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Tripati, S.

    as an excellent natural harbour. The important antiquities include varieties of stone anchors, which are very similar to those reported from Dwarka and Bet Dwarka. The identification of ancient anchorage points between water depth of 5 and 15 m is another...

  12. Anchorage-independent growth of pocket protein-deficient murine fibroblasts requires bypass of G2 arrest and can be accomplished by expression of TBX2

    NARCIS (Netherlands)

    Vormer, Tinke L; Foijer, Floris; Wielders, Camiel L C; te Riele, Hein

    2008-01-01

    Mouse embryonic fibroblasts (MEFs) deficient for pocket proteins (i.e., pRB/p107-, pRB/p130-, or pRB/p107/p130-deficient MEFs) have lost proper G(1) control and are refractory to Ras(V12)-induced senescence. However, pocket protein-deficient MEFs expressing Ras(V12) were unable to exhibit anchorage-

  13. Anchorage of TiO2-blasted, HA-coated, and machined implants: an experimental study with rabbits

    DEFF Research Database (Denmark)

    Gotfredsen, K; Wennerberg, A; Johansson, C

    1995-01-01

    The purpose of this study was to evaluate the histometrical and biomechanical anchorage of TiO2-blasted implants and TiO2-blasted implants coated with hydroxyapatite. The control implants were machined. Twenty-six rabbits had a total of 156 implants placed in the proximal part of the tibia. Each...... rabbit had a machined, a TiO2-blasted, and a TiO2-blasted, HA-coated implant placed in each tibia. After a healing period of 3 and 12 weeks, respectively, the implants placed in the right tibia were used for removal torque test, and the implants placed in the left tibia were used for histomorphometrical...... measurements. Preoperatively, implants from the same batches were examined topographically with a TopScan 3D system. The TiO2-blasted implants demonstrated significantly higher removal torque values than the machined implants, and they also had a significantly more irregular surface. Furthermore, significantly...

  14. [Low-cost simple anchorage systems in the removable hybrid prosthesis. Locator Root Attachment and Würzburg post].

    Science.gov (United States)

    Teubner, Eckart; Galindo, Martha L; Arnold, Dario; Marinello, Carlo P

    2009-01-01

    For a simple and provisional retention of a removable prosthesis, less expensive direct retainers are an option compared to indirect cast gold copings with attachment. The Dalbo-Rotex-retainer and the Ticap-system are clinically established. The Locator Root attachment and the Würzburger Stift were recently introduced. The Locator Root attachment uses a massive profiled cylindrical post as a radicular anchorage. The Würzburger Stift has a small endodontic part which is retained by four spreadable lamellae in a convergent cavity. They further differ in the design of the male and female part. Depending on the clinical situation these characteristics can offer benefits and disadvantages. Both systems are documented and their indication, advantages and restrictions are discussed with clinical relevance.

  15. Recombinant differential anchorage probes that tower over the spatial dimension of intracellular signals for high content screening and analysis.

    Science.gov (United States)

    Schembri, Laura; Zanese, Marion; Depierre-Plinet, Gaelle; Petit, Muriel; Elkaoukabi-Chaibi, Assia; Tauzin, Loic; Florean, Cristina; Lartigue, Lydia; Medina, Chantal; Rey, Christophe; Belloc, Francis; Reiffers, Josy; Ichas, François; De Giorgi, Francesca

    2009-12-01

    Recombinant fluorescent probes allow the detection of molecular events inside living cells. Many of them exploit the intracellular space to provide positional signals and, thus, require detection by single cell imaging. We describe here a novel strategy based on probes capable of encoding the spatial dimension of intracellular signals into "all-or-none" fluorescence intensity changes (differential anchorage probes, DAPs). The resulting signals can be acquired in single cells at high throughput by automated flow cytometry, (i) bypassing image acquisition and analysis, (ii) providing a direct quantitative readout, and (iii) allowing the exploration of large experimental series. We illustrate our purpose with DAPs for Bax and the effector caspases 3 and 7, which are keys players in apoptotic cell death, and show applications in basic research, high content multiplexed library screening, compound characterization, and drug profiling.

  16. The Akashi Kaikyo Bridge and the Storebælt Bridge

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    With the completion of the Akashi Kaikyo Bridge and the Storebælt East Bridge the development of the suspension bridge technology in the 20th century has manifested itself in two impressive structures. With the present echnology may bridges of similar (and also more modest) dimensions...... will undoubtedly be built far into the next century. For bridges going beyond the spans of existing bridges it is, however, likely that new concepts will be developed....

  17. Effect of molar intrusion with temporary anchorage devices in patients with anterior open bite: a systematic review

    Directory of Open Access Journals (Sweden)

    Ahmad Saleem Alsafadi

    2016-03-01

    Full Text Available Abstract Objective The objective of the study is to assess the effect of molar intrusion with temporary anchorage devices on the vertical facial morphology and mandibular rotation during open bite treatment in the permanent dentition. Methods We performed a systematic review of the published data in seven electronic databases up to September 2015. We considered studies for inclusion if they were examining the effects of posterior teeth intrusion on the vertical facial morphology with open bite malocclusion in the permanent dentition. Study selection, risk of bias assessment, and data-extraction were performed in duplicate. Meta-analysis was not possible due to dissimilarity and heterogeneity among the included studies. Results Out of the 42 articles that met the initial eligibility criteria, 12 studies were finally selected. Low level of scientific evidence was identified after risk of bias assessment of the included studies with no relevant randomized controlled trial performed. Out of the 12 selected studies, five studies used miniplates and seven studies used miniscrews. Mandibular counterclockwise rotation was found to be between 2.3° and 3.9° in six studies (as sassed by mandibular plane angle, between MeGo or GoGn and SN or FH plane while it was less than 2° in the remaining studies. Conclusions Current weak evidence suggests that molar intrusion with temporary anchorage devices may cause mandibular counterclockwise autorotation. Future well-conducted and clearly reported multicenter randomized controlled trials that include a non-treatment control group are needed to make robust recommendations regarding the amount of mandibular rotation during open bite treatments.

  18. Analysis of Vehicle Seat Belt Anchorage Strength%汽车安全带固定点强度分析

    Institute of Scientific and Technical Information of China (English)

    邓国红; 杨浩; 杨鄂川; 张勇

    2011-01-01

    To analyze the vehicle seat belt anchorage strength, the finite element model of body-in- white, seats, seat belts and the body module (hip block, shoulder block cessing software Hypermesh, the explicit solution method in LS-DYNA ) is is established by pre-pro- used, the specified load condition is set according to the national standard, an accurate prediction is made on whether the structure can meet the standard, a method which uses the FEM to analyze the seat belt anchorage strength is found. This method can be extended to other quasi-static strength analysis problems, and analyze the model which is larger and more difficuh to calculate using the implicit integration, which has a strong practicality in product development.%为了进行汽车安全带固定点强度分析,运用有限元分析软件Hypermesh建立白车身、座椅、安全带、人体模块(臀块和肩块)有限元模型。采用LS-DYNA的显式求解模块,按照国家标准设置规定的载荷,分析结构通过标准的可能性。验证了运用有限元显式积分分析汽车安全带固定点强度的方法。该方法可推广到其他准静态强度分析中,用于分析那些比较大的、隐式积分计算比较困难的模型。

  19. Characterization of the aspects of osteoprogenitor cell interactions with physical tetracalcium phosphate anchorage on titanium implant surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Chia-Ling [Advanced Medical Devices and Composites Laboratory, Department of Fiber and Composite Materials, Feng Chia University, Taichung 40724, Taiwan (China); Dental Medical Devices and Materials Research Center, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chang, Ya-Yuan; Liou, Cian-Hua [Alliance Global Technology Co., Ltd., Kaohsiung Medical Device Special Zone in Southern Taiwan Science Park, Kaohsiung 82151, Taiwan (China); Chen, Wen-Cheng, E-mail: wencchen@fcu.edu.tw [Advanced Medical Devices and Composites Laboratory, Department of Fiber and Composite Materials, Feng Chia University, Taichung 40724, Taiwan (China)

    2015-04-01

    Well-designed implants are used not only to modify the geometry of the implant but also to change the chemical properties of its surfaces. The present study aims to assess the biofunctional effects of tetracalcium phosphate (TTCP) particles as a physical anchor on the implant surface derived through sandblasting. The characteristics of the surface, cell viability, and alkaline phosphatase (ALP) activity toward osteoprogenitor cells (D1) were obtained. D1 cells were cultured on a plain surface that underwent sandblasting and acid etching (SLA) (control SLA group) and on different SLA surfaces with different anchoring TTCP rates (new test groups, M and H). The mean anchoring rates were 57% (M) and 74% (H), and the anchored thickness was estimated to range from 12.6 μm to 18.3 μm. Compared with the control SLA surface on Ti substrate, the new test groups with different TTCP anchoring rates (M and H) failed to improve cell proliferation significantly but had a well-differentiated D1 cell phenotype that enhanced ALP expression in the early stage of cell cultures, specifically, at day 7. Results suggest that the SLA surface with anchored TTCP can accelerate progenitor bone cell mineralization. This study shows the potential clinical application of the constructed geometry in TTCP anchorage on Ti for dental implant surface modification. - Highlights: • TTCP (tetracalcium phosphate) as a physical anchorage on implant is characterized. • Theoretical values of anchored thickness and capping areas were estimated. • TTCP anchored by sandblasting can accelerate progenitor bone cell mineralization. • TTCP anchored on SLA (sandblasting and acid etching) surface is a promising method.

  20. River ice jams at bridges

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, D. [New Brunswick Dept. of Transportation, Fredericton, NB (Canada); Beltaos, S. [National Water Research Institute, Burlington, ON (Canada)

    2000-12-01

    Ice jamming, known to cause high water levels at even moderate river flows, is described as both the main and least understood source of ice-related bridge damages. This paper describes a joint study by the New Brunswick Department of Transportation, the Department of the Environment, local governments, and the National Water Research Institute, designed to address problems associated with the interaction of ice jams and bridges. The study consists of collecting information at each of four sites in New Brunswick including: historical data on ice jam locations, causes, and water levels; channel bathymetry, width and slope within each study centred at the respective bridge; and documentation of ice conditions throughout the ice season, including measurement of ice cover thickness, observation of breakup mechanisms, times, causes, characteristics and possible impacts of ice jam release. Data analysis will include determination of high stages due to ice jams or surges caused by upstream ice jam releases, scour potential of surges, and quantification of the structure's capacity to restrain ice movement and to cause jams. The principal objective of the study is to advance beyond empiricism and to develop rational design criteria for bridges by anticipating the effects of climate changes and by incorporating local meteorological and hydrometric records into bridge design for added safety.

  1. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  2. A strange bridge by Leonardo

    CERN Document Server

    Huylebrouck, Dirk

    2013-01-01

    On folio 855 recto of the Codex Atlanticus, Leonardo da Vinci drew three 'easily movable' bridges, but one of them is enigmatic: all 'replicas' in Leonardo museums and exhibitions come as a surprise, to say the least, to any engineer or architect whose attention is drawn to it. This is the case for models in Amboise (France), Chicago and Portland (USA), Florence (Italy) and for the one of the traveling exhibition by the Australian company 'Grande Exhibitions' that already visited 40 major cities in the world. All 'replicas' of the bridge model attributed to Leonardo have pillars standing on the deck of the bridge, while the deck is suspended by cables attached on these pillars. At first sight this problem does not catch the attention of the observer, as the bridge seems to be a mixed form of a beam and a suspension bridge, but it was not overlooked by my colleague architect-engineer Dr. Laurens Luyten (Gent, Belgium). Yet, after a TV-interview in Brussels so much pressure was exerted by some of the museum col...

  3. Thermal bridges of modern windows

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Møller, Eva B.; Nielsen, Anker

    2013-01-01

    With its focus on reduced energy consumption, contemporary housing construction requires a highly insulated and airtight building envelope with as few thermal bridges as possible.Windows must be carefully designed, as thermal bridges can lead to surface condensation or mold growth, even...... if the window has an U-factor of 1 W/(m2·K) or lower. This paper describes the development of modern, energy efficient Danish windows with reduced thermal bridges. It focuses on materials, geometry, and sealing of window panes based on a literature review. Examples of modern windows are presented. Experience...... with the minimum acceptable surface temperature regarding surface condensation or mold growth, implemented in the Danish Building Regulations in 2010, and the calculation method for this temperature based on international standards is discussed. The introduction of the minimum acceptable surface temperature has...

  4. An Expert System for Concrete Bridge Management

    DEFF Research Database (Denmark)

    Brito, J. de; Branco, F. A.; Thoft-Christensen, Palle

    1997-01-01

    management systems are presently being implemented by bridge authorities in several countries. The prototype of an expert system for concrete bridge management is presented in this paper, with its functionality relying on two modules. The inspection module relies on a periodic acquisition of field......The importance of bridge repair versus new bridge construction has risen in recent decades due to high deterioration rates that have been observed in these structures. Budgets both for building new bridges and keeping the existing ones are always limited. To help rational decision-making, bridge...

  5. Excitation Methods for Bridge Structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, C.R.; Duffy, T.A.; Cornwell, P.J.; Doebling, S.W.

    1999-02-08

    This paper summarizes the various methods that have been used to excited bridge structures during dynamic testing. The excitation methods fall into the general categories of ambient excitation methods and measured-input excitation methods. During ambient excitation the input to the bridge is not directly measured. In contrast, as the category label implies, measured-input excitations are usually applied at a single location where the force input to the structure can be monitored. Issues associated with using these various types of measurements are discussed along with a general description of the various excitation methods.

  6. Balanced bridge feedback control system

    Science.gov (United States)

    Lurie, Boris J. (Inventor)

    1990-01-01

    In a system having a driver, a motor, and a mechanical plant, a multiloop feedback control apparatus for controlling the movement and/or positioning of a mechanical plant, the control apparatus has a first local bridge feedback loop for feeding back a signal representative of a selected ratio of voltage and current at the output driver, and a second bridge feedback loop for feeding back a signal representative of a selected ratio of force and velocity at the output of the motor. The control apparatus may further include an outer loop for feeding back a signal representing the angular velocity and/or position of the mechanical plant.

  7. Optimum selection on bridge erection with floating crane in East China Sea Bridge and Hangzhou Bay Bridge

    Institute of Scientific and Technical Information of China (English)

    Shunquan Qin; Pu Zhou; Youheng Hua

    2004-01-01

    @@ Introduction With the rapid development of China′s economy, many bridges will be built over the Chinese coastal waters of Pacific Ocean. Among them, construction of East China Sea Bridge has been commenced in June 2001, and will be completed at the end of 2005, Hangzhou Bay Bridge was also started to construct in June 2003(Fig. 1). These two ultralong bridges are designed as twin expressway bridges standing side by side each carries a 3-lane one-way carriageway. The total width is 31.5m and 33.0m respectively. East China Sea Bridge starts from Nanhui District, Shanghai and extends to the Yangshan Deep Water Port Area, which is located at one of the Qiqu Islands. The total length of the bridge is about 31.0 km, in which 25 km are on the sea, and 22 km is in the unnavigable region. Hangzhou Bay Bridge across the mouth of Qiantang River.

  8. Is myocardial bridging a bridge connecting to cardiovascular events?

    Institute of Scientific and Technical Information of China (English)

    LI Jian-jun

    2010-01-01

    @@ Coronary arteries and their major branches usually course on the surface of the heart in the subepicardial tissue. However, a muscle hber overlying the intramyocardial segment of an epicardial coronary artery was defined as myocardial bridging (MB), and subsequently the artery coursing within the myocardium is called a tunneled artery.

  9. Mechanical behavior experiment of wedge-bond anchorage for CFRP-tendons%CFRP筋复合型锚具的受力性能试验

    Institute of Scientific and Technical Information of China (English)

    王军; 李明君; 蔡东升; 刘德鑫

    2012-01-01

    In order to investigate the influence of main design parameters on anchorage performance and internal stress distribution of wedge-bond anchorage for CFRP tendons, five groups of parameter tests on wedge-bond anchorage were designed. The ultimate load, slip deformation of anchor ring and stress of metal sleeve stations were determined. The influence of design parameters on anchorage performance, the tress distribution and variation of metal sleeve were contrastively investigated through static loading testing. The results show that the anchorage performance with metal sleeve thickness of 2 mm, a wedge length of 65 mm, bond length of 500 mm is optimal. The anchor between wedge and metal sleeve is good without relative displacement. The tress distribution and variation of metal sleeve can reflect the internal stress distribution of anchorage, and the perk of stress curve indicates bonding failure between colloid and CFRP tendon near the observation point.%为研究CFRP筋复合型锚具的主要设计参数对锚固性能的影响及锚具内部受力情况,设计了5个复合型锚具的参数静载试验,测量了锚具的极限荷载、锚环-CFRP筋间滑移变形和金属筒测点应变,通过静载试验对比分析了各设计参数对锚固效果的影响,以及金属筒表面应力的分布情况与变化规律.研究结果表明:当金属筒壁厚为2 mm,夹片夹持长度为65 mm,粘结长度为500 mm时,锚具的锚固性能较好;夹片-金属筒间锚固良好,无滑移;金属筒应力分布与变化可反映锚具内部受力情况,测点应力曲线峰值预示该位置附近的胶体与CFRP筋间的粘结破坏.

  10. Architectural engineering of FRP bridges

    OpenAIRE

    Smits, J.E.P.

    2014-01-01

    This paper deals with the use of Fibre Reinforced Polymers (FRP's) in architectural and structural bridge design. The challenges and opportunities that come with this relatively new material are discussed. An inventory is made of recent engineers' solutions in FRP, followed by a discussion on architectural application of FRP's derived from the authors architectural practice.

  11. Bridge Aesthetics and Structural Honesty

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    In bridges the overall form must be chosen with due respect to the transmission of forces if efficient structures shall be created, The design must therefore be governed by experienced structural engineers - in some cases assisted by aesthetic advisers on specific issues. Some basic requirements...

  12. Intercellular bridges in vertebrate gastrulation.

    Directory of Open Access Journals (Sweden)

    Luca Caneparo

    Full Text Available The developing zebrafish embryo has been the subject of many studies of regional patterning, stereotypical cell movements and changes in cell shape. To better study the morphological features of cells during gastrulation, we generated mosaic embryos expressing membrane attached Dendra2 to highlight cellular boundaries. We find that intercellular bridges join a significant fraction of epiblast cells in the zebrafish embryo, reaching several cell diameters in length and spanning across different regions of the developing embryos. These intercellular bridges are distinct from the cellular protrusions previously reported as extending from hypoblast cells (1-2 cellular diameters in length or epiblast cells (which were shorter. Most of the intercellular bridges were formed at pre-gastrula stages by the daughters of a dividing cell maintaining a membrane tether as they move apart after mitosis. These intercellular bridges persist during gastrulation and can mediate the transfer of proteins between distant cells. These findings reveal a surprising feature of the cellular landscape in zebrafish embryos and open new possibilities for cell-cell communication during gastrulation, with implications for modeling, cellular mechanics, and morphogenetic signaling.

  13. Noise Considerations in Resistance Bridges

    DEFF Research Database (Denmark)

    Diamond, Joseph M.

    1963-01-01

    A signal-to-noise analysis is made of the Wheatstone bridge, where the unknown and standard resistors may be at different temperatures, a situation which occurs in resistance thermometry. The limiting condition is assumed to be dissipation in the unknown resistor. It is shown that the ratio arms ...

  14. The Wien Bridge Oscillator Family

    DEFF Research Database (Denmark)

    Lindberg, Erik

    2006-01-01

    A tutorial in which the Wien bridge family of oscillators is defined and investigated. Oscillators which do not fit into the Barkhausen criterion topology may be designed. A design procedure based on initial complex pole quality factor is reported. The dynamic transfer characteristic...

  15. Architectural engineering of FRP bridges

    NARCIS (Netherlands)

    Smits, J.E.P.

    2014-01-01

    This paper deals with the use of Fibre Reinforced Polymers (FRP's) in architectural and structural bridge design. The challenges and opportunities that come with this relatively new material are discussed. An inventory is made of recent engineers' solutions in FRP, followed by a discussion on archit

  16. History of cable-stayed bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    The principle of supporting a bridge deck by inclined tension members leading to towers on either side of the span has been known for centuries. However, the real development of cable-stayed bridges did not begin before the 1950s. Since then the free span has been increased from 183 m...... in the Strömsund Bridge (from 1955) to 890 m in the Tatara Bridge (from 1999)....

  17. Building Bridges One Line at a Time

    Science.gov (United States)

    Grigsby, Cathy Murray

    2012-01-01

    In this article, first-grade students were taught the different kinds of lines that were part of the construction of various bridges--the curved lines of the arches of stone bridges, straight lines connecting the cables of a suspension bridge, vertical lines, horizontal lines, and so on. They gained practice in drawing structures and in fine brush…

  18. Comparison between Modern Violin Bridge and Baroque Violin Bridge by Photoelastic Observation and Frequency Analysis

    Science.gov (United States)

    Matsutani, Akihiro

    2004-05-01

    A comparison between the modern bridge and the baroque bridge of the violin by photoelastic observation was carried out. The relationship between the stress part and the hole is symmetric in the modern and baroque bridges. The measured spectral envelopes of baroque bridges are similar to those of modern bridges in D- or G-strings, and have peaks at a frequency higher than those of modern bridges in E-string. The visualization method as used in this study may provide hints for the design of violin bridges.

  19. Beginning Course Surveys: Bridges for Knowing and Bridges for Being

    Directory of Open Access Journals (Sweden)

    David Starr-Glass

    2011-06-01

    Full Text Available The use of a participant survey, administered at the outset of an online course, can provide information useful in the management of the learning environment and in its subsequent redesign. Such information can clarify participants’ prior experience, expectations, and demographics. But the very act of enquiring about the learner also signals the instructor’s social presence, relational interest, and desire to enter into an authentic dialogue. This study examines the use of participant surveys in online management courses. The first section discusses the informational bridges that this instrument provides. The second section considers survey responses to open-ended questions dealing with student sentiments. This analysis suggests that the survey plays a valuable part in accentuating social presence and in initiating relational bridges with participants.

  20. ESTIMATION OF ECONOMIC EXPEDIENCY OF «BRIDGE-PRE-BRIDGE TERRITORY» SYSTEM

    Directory of Open Access Journals (Sweden)

    A. A. Lapko

    2008-01-01

    Full Text Available The paper considers principles that form «Bridge-Pre-Bridge Territory» system. The method is proposed for calculation of expenses on technical research for development of projects on usage of pre-bridge territories. Usage of site class number for natural conditions makes it possible to estimate investment attractiveness of «Bridge-Pre-Bridge Territory» system.

  1. 33 CFR 115.70 - Advance approval of bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Advance approval of bridges. 115... BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.70 Advance approval of bridges. (a) The General Bridge Act of 1946 requires the approval of the location and plans of bridges...

  2. Performance analysis of LAN bridges and routers

    Science.gov (United States)

    Hajare, Ankur R.

    1991-01-01

    Bridges and routers are used to interconnect Local Area Networks (LANs). The performance of these devices is important since they can become bottlenecks in large multi-segment networks. Performance metrics and test methodology for bridges and routers were not standardized. Performance data reported by vendors is not applicable to the actual scenarios encountered in an operational network. However, vendor-provided data can be used to calibrate models of bridges and routers that, along with other models, yield performance data for a network. Several tools are available for modeling bridges and routers - Network II.5 was used. The results of the analysis of some bridges and routers are presented.

  3. Leucine zipper structure of TSC-22 (TGF-beta stimulated clone-22) markedly inhibits the anchorage-independent growth of salivary gland cancer cells.

    Science.gov (United States)

    Hino, Satoshi; Kawamata, Hitoshi; Omotehara, Fumie; Uchida, Daisuke; Begum, Nasima-Mila; Yoshida, Hideo; Sato, Mitsunobu; Fujimori, Takahiro

    2002-01-01

    Several investigators have demonstrated that TGF-beta stimulated clone-22 (TSC-22) regulates cell growth and differentiation, and cell death. TSC-22 is a putative transcriptional regulator containing a leucine zipper-like structure and a nuclear export signal. We previously showed the cytoplasmic localization of TSC-22 and the nuclear translocation of TSC-22 concomitant with induction of apoptosis in salivary gland cancer cells. In the present study, we attempted to identify the active domain of TSC-22 protein that regulated the biological functions of TSC-22. We constructed three mammalian expression vectors, which could produce full length TSC-22 only in cytoplasm, the leucine zipper structure of TSC-22 in both cytoplasm and nucleus, and the leucine zipper structure only in nucleus. Then, we transfected a salivary gland cancer cell line, HSG with these expression vectors, and investigated the growth profile of the transfectants. None of the TSC-22 constructs inhibited the monolayer growth and the anchorage-dependent colony formation of HSG cells. However, the leucine zipper structure of TSC-22 markedly inhibited the anchorage-independent colony formation of HSG cells (pway ANOVA). Full length TSC-22 also suppressed the anchorage-independent colony formation of HSG cells, although the effect of full length TSC-22 was much lower than those of the leucine zipper constructs. These observations suggest that the leucine zipper structure in TSC-22 protein is an active domain that negatively regulates the growth of salivary gland cancer cells.

  4. Changes in strain patterns after implantation of a short stem with metaphyseal anchorage compared to a standard stem: an experimental study in synthetic bone

    Directory of Open Access Journals (Sweden)

    Jens Gronewold

    2014-03-01

    Full Text Available Short stem hip arthroplasties with predominantly metaphyseal fixation, such as the METHA® stem (Aesculap, Tuttlingen, Germany, are recommended because they are presumed to allow a more physiologic load transfer and thus a reduction of stress-shielding. However, the hypothesized metaphyseal anchorage associated with the aforementioned benefits still needs to be verified. Therefore, the METHA short stem and the Bicontact® standard stem (Aesculap, Tuttlingen, Germany were tested biomechanically in synthetic femora while strain gauges monitored their corresponding strain patterns. For the METHA stem, the strains in all tested locations including the region of the calcar (87% of the non-implanted femur were similar to conditions of synthetic bone without implanted stem. The Bicontact stem showed approximately the level of strain of the non-implanted femur on the lateral and medial aspect in the proximal diaphysis of the femur. On the anterior and posterior aspect of the proximal metaphysis the strains reached averages of 78% and 87% of the non-implanted femur, respectively. This study revealed primary metaphyseal anchorage of the METHA short stem, as opposed to a metaphyseal-diaphyseal anchorage of the Bicontact stem.

  5. Problems associated with nondestructive evaluation of bridges

    Science.gov (United States)

    Prine, David W.

    1995-05-01

    The US has 542,000 bridges that consume billions of dollars per year in construction, rehabilitation, and maintenance funds and which are the lifelines of US commerce. The 1992 ISTEA (Intermodal Surface Transportation Efficiency Act) mandates the implementation of a quantitative computerized bridge management system by 1996. A prime need of such a system are quantitative bridge inspection methods to feed accurate reliable condition information to the huge database of bridges. Nondestructive evaluation (NDE) will fill a critical need in the implementation of effective bridge management. However, many serious barriers exist to the widespread routine application of this technology to bridges. This paper provides an overview of the typical problems associated with applying NDE to bridges.

  6. Parabolic metamaterials and Dirac bridges

    Science.gov (United States)

    Colquitt, D. J.; Movchan, N. V.; Movchan, A. B.

    2016-10-01

    A new class of multi-scale structures, referred to as `parabolic metamaterials' is introduced and studied in this paper. For an elastic two-dimensional triangular lattice, we identify dynamic regimes, which corresponds to so-called `Dirac Bridges' on the dispersion surfaces. Such regimes lead to a highly localised and focussed unidirectional beam when the lattice is excited. We also show that the flexural rigidities of elastic ligaments are essential in establishing the `parabolic metamaterial' regimes.

  7. Severe ASR damaged concrete bridges

    DEFF Research Database (Denmark)

    Antonio Barbosa, Ricardo; Gustenhoff Hansen, Søren

    2015-01-01

    Technical University of Denmark (DTU) and University of Southern Denmark (SDU) have conducted several full-scale experiments with severe ASR deteriorated bridges. This paper presents few and preliminary results from both the shear tests and the measuring of the material properties. The shear test...... show that the shear capacity is almost unaffected of ASR despite significant reduction in compressive concrete strength. Furthermore, measurements show a significant tensile reinforcement strain developed due to ASR expansion....

  8. Inspection Strategies for Concrete Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    1989-01-01

    In this paper an optimal inspection strategy for concrete bridges based on periodic routine and detailed inspections is presented. The failure mode considered is corrosion of the reinforcement due to chlorides. A simple modelling of the corrosion and of the inspection strategy is presented....... The optimal inspection strategy is determined from an optimization problem, where the design variables are time intervals between detailed inspections and the concrete cover. The strategy is illustrated on a simple structure, namely a reinforced concrete beam....

  9. Chlamydia induces anchorage independence in 3T3 cells and detrimental cytological defects in an infection model.

    Directory of Open Access Journals (Sweden)

    Andrea E Knowlton

    Full Text Available Chlamydia are gram negative, obligate intracellular bacterial organisms with different species causing a multitude of infections in both humans and animals. Chlamydia trachomatis is the causative agent of the sexually transmitted infection (STI Chlamydia, the most commonly acquired bacterial STI in the United States. Chlamydial infections have also been epidemiologically linked to cervical cancer in women co-infected with the human papillomavirus (HPV. We have previously shown chlamydial infection results in centrosome amplification and multipolar spindle formation leading to chromosomal instability. Many studies indicate that centrosome abnormalities, spindle defects, and chromosome segregation errors can lead to cell transformation. We hypothesize that the presence of these defects within infected dividing cells identifies a possible mechanism for Chlamydia as a cofactor in cervical cancer formation. Here we demonstrate that infection with Chlamydia trachomatis is able to transform 3T3 cells in soft agar resulting in anchorage independence and increased colony formation. Additionally, we show for the first time Chlamydia infects actively replicating cells in vivo. Infection of mice with Chlamydia results in significantly increased cell proliferation within the cervix, and in evidence of cervical dysplasia. Confocal examination of these infected tissues also revealed elements of chlamydial induced chromosome instability. These results contribute to a growing body of data implicating a role for Chlamydia in cervical cancer development and suggest a possible molecular mechanism for this effect.

  10. fau and its ubiquitin-like domain (FUBI) transforms human osteogenic sarcoma (HOS) cells to anchorage-independence.

    Science.gov (United States)

    Rossman, Toby G; Visalli, Melissa A; Komissarova, Elena V

    2003-03-27

    Arsenite is the most likely carcinogenic form of arsenic in the environment. Previously, expression cloning for cDNAs whose overexpression confers arsenite-resistance in Chinese hamster V79 cells identified two genes: fau and a novel gene, asr2. The fau gene encodes a ubiquitin-like protein (here called FUBI) fused to the ribosomal S30 protein. Since the expression of the fox sequence (antisense to fau) increased the tumorigenicity of a mouse sarcoma virus, it was proposed that fau might be a tumor suppressor gene. We intended to test its ability to block arsenite-induced transformation of human osteogenic sarcoma (HOS) cells to anchorage-independence. Instead, we found that overexpressing fau itself was able to transform HOS cells. When the two domains were expressed separately, only FUBI was transforming and only the S30 domain conferred arsenite resistance. An incidental finding was the transforming activity of the selectable marker, hyg. FUBI belongs to the ubiquitin-like protein group that is capable of forming conjugates to other proteins, although none have so far been identified. Alternatively, FUBI may act as a substitute or inhibitor of ubiquitin, to which it is most closely related, or to close ubiquitin-like relatives UCRP, FAT10, and/or Nedd8.

  11. Cochleates bridged by drug molecules.

    Science.gov (United States)

    Syed, Uwais M; Woo, Amy F; Plakogiannis, Fotios; Jin, Tuo; Zhu, Hua

    2008-11-03

    A new type of cochleate, able to microencapsulate water-soluble cationic drugs or peptides into its inter-lipid bi-layer space, was formed through interaction between negatively charged lipids and drugs or peptides acting as the inter-bi-layer bridges instead of multi-cationic metal ions. This new type of cochleate opened up to form large liposomes when treated with EDTA, suggesting that cationic organic molecules can be extracted from these cochleates in a way similar to multivalent metal ions from metal ion-bridged cochleates. Cochleates can be produced in sub-micron size using a method known as "hydrogel isolated cochleation" or simply by increasing the ratio of multivalent cationic peptides over negatively charged liposomes. When nanometer-sized cochleates and liposomes containing the same fluorescent labeled lipid component were incubated with human fibroblasts cells under identical conditions, cells exposed to cochleates showed bright fluorescent cell surfaces, whereas those incubated with liposomes did not. This result suggests that cochleates' edges made them fuse with the cell surfaces as compared to edge free liposomes. This mechanism of cochleates' fusion with cell membrane was supported by a bactericidal activity assay using tobramycin cochleates, which act by inhibiting intracellular ribosomes. Tobramycin bridged cochleates in nanometer size showed improved antibacterial activity than the drug's solution.

  12. Salt bridges: geometrically specific, designable interactions.

    Science.gov (United States)

    Donald, Jason E; Kulp, Daniel W; DeGrado, William F

    2011-03-01

    Salt bridges occur frequently in proteins, providing conformational specificity and contributing to molecular recognition and catalysis. We present a comprehensive analysis of these interactions in protein structures by surveying a large database of protein structures. Salt bridges between Asp or Glu and His, Arg, or Lys display extremely well-defined geometric preferences. Several previously observed preferences are confirmed, and others that were previously unrecognized are discovered. Salt bridges are explored for their preferences for different separations in sequence and in space, geometric preferences within proteins and at protein-protein interfaces, co-operativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction on formation, and degree of burial. Salt bridges occur far more frequently between residues at close than distant sequence separations, but, at close distances, there remain strong preferences for salt bridges at specific separations. Specific types of complex salt bridges, involving three or more members, are also discovered. As we observe a strong relationship between the propensity to form a salt bridge and the placement of salt-bridging residues in protein sequences, we discuss the role that salt bridges might play in kinetically influencing protein folding and thermodynamically stabilizing the native conformation. We also develop a quantitative method to select appropriate crystal structure resolution and B-factor cutoffs. Detailed knowledge of these geometric and sequence dependences should aid de novo design and prediction algorithms.

  13. Estimation of load redistribution on a cable-stayed bridge using a combination of sensing techniques

    Science.gov (United States)

    Zonta, Daniele; Esposito, Paolo; Molignoni, Marco; Pozzi, Matteo; Zandonini, Riccardo; Wang, Ming; Zhao, Yang; Inaudi, Daniele; Posenato, Daniele; Glisic, Branko

    2012-04-01

    The motivation of this work is the installation of a monitoring system on a new cable-stayed bridge spanning the Adige River 10 km north of the town of Trento. This is a statically indeterminate structure, having a composite steel-concrete deck of length 260 m overall, supported by 12 stay cables, 6 per deck side. These are full locked steel cables of diameters 116 mm and 128 mm, designed for operational loads varying from 5000 to 8000 kN. The structural redundancy suggests that plastic load redistribution among the cables can be expected in the long term. To monitor such load redistribution, the owner decided to install a monitoring system to measure cable stress; the precision specified was of the order of few MPa. However no cable release or any form of on-site calibration involving tension change was allowed. The solution found was a combination of built-on-site electromagnetic and fiber-optic elongation gauges, these appropriately distributed on both the cables and the anchorages. We discuss how the set of gauges allows tension and elongation measurement with the appropriate precision, and compare the initial monitoring results with the tension estimates made using a non-destructive vibration test.

  14. Overall Design of Baitanhu Lake Bridge%白潭湖大桥总体设计

    Institute of Scientific and Technical Information of China (English)

    张全阳

    2014-01-01

    基于城市桥梁的景观要求,白潭湖大桥主桥采用纵向对称布置的(150+150) m混凝土独塔斜拉桥的设计方案。桥塔以拱为形态元素,采用椭圆形拱塔结构;主梁采用预应力混凝土单箱三室斜腹板箱梁,人行道置于斜拉索锚固区外侧;斜拉索采用扇形空间双索面布置,主梁上锚固采用混凝土齿块锚固形式,塔上锚固采用混凝土锚块+隔板的锚固形式;过渡墩采用花瓶形板式墩。桥塔采用爬模施工,桥塔横梁采用分节段浇筑,设置2 m合龙段;主梁采用分节段支架现浇施工,共分13个施工节段。有限元计算结果表明,结构受力满足规范要求。%Given the demands of landscape effect of city bridges ,the design scheme of a (150+150) m concrete single pylon cable-stayed bridge that is symmetrically arranged in the longitudinal direction is chosen for the main bridge of Baitanhu Lake Bridge .The pylon which is basically an arch is designed as an elliptic arched pylon structure .The main girder is the prestressed concrete three-cell single box structure with inclined webs .The sidewalk is arranged along the outer side of the anchorage zone of the stay cables . The stay cables are fanned out in spatial double cable planes ,which are anchored to the main girder via concrete teeth ,but anchored to the pylon with the assistance of concrete blocks and bulkheads .T he transitional piers are vase-shaped plate piers . The pylon is constructed by climbing formwork and the pylon cross beam is cast in segments with a 2 m long closure section .The main girder is cast in segments on scaffoldings and a total of 13 construction segments are made .The results of the finite element calculation indicate that the force conditions of the structure can meet the code requirements .

  15. 桥梁缆索金属损伤无损检测方法%Nondestructive Testing Method for Metallic Flaws of Bridge Cables

    Institute of Scientific and Technical Information of China (English)

    武新军; 贲安然; 徐江

    2012-01-01

    缆索广泛应用于斜拉桥、悬索桥和拱形桥等桥梁结构中,其有效金属承载面积直接关系到桥梁安全。在分析桥梁缆索自身结构和使用工况的基础上,论述了桥梁缆索无损检测中遇到的难点,分析了可能应用于桥梁缆索金属损伤的无损检测方法的特点和局限性,其中声发射法可用于缆索的长期监测,但仅能给出相对检测结果;射线法和磁性检测法可用于缆索的逐点扫描检测,但检测移动辅助装置复杂;磁致伸缩导波检测方法可实现远距离的包括锚固区在内的金属损伤检测,但信号解释复杂。最后,提出了桥梁缆索磁致伸缩导波快速扫查和磁性精细扫查相结合的无盲区检测方法,该研究将促进桥梁缆索无损检测技术的深入发展。%Cables and wire ropes are mostly employed in the structure of cable-stayed bridges, suspension bridges and arch bridge. Its effective metallic loading area determines the safety of the bridge. Based on the analysis of the bridge cable structure and its working condition, main problems in nondestructive testing of bridge cables are described in this paper. Then, the possible method for NDT of bridge cables including their characteristics and limits are given. The acoustic emission testing method can be used in the cable on-line condition and only can give relative results of different cable conditions. The radiography and magnetic testing methods can scan along the cable, but the complicated auxiliary apparatus is required. The magnetostrictive guided wave testing method can detect far flaws of cables, which include the anchorage zone, but its signal interpretation requires complex knowledge. In the last, a blind zone free NDT method for the bridge cable which is to combine rapid scanning and magnetic precise testing together is proposed. The above research work will advance further development of nondestructive testing technique for the bridge cables.

  16. Evaluation method research on prestressed concrete bridges

    Institute of Scientific and Technical Information of China (English)

    HUANG Qiao; LIN Yang-zi; REN Yuan

    2008-01-01

    Considering the construction features of prestressed concrete bridge, the comprehensive evaluation method about the bridge damage conditions are studied. Particular attentions are paid on establishing a multi-level evaluation model for damaged prestressed concrete bridge, and the evaluation indices of the model as well as the rating standards are defined in the model. A normal relative function about the evaluation indices of each element is developed to calculate the relative degree, and for each element which is no sub-level elements. When evaluating the elements in sub-item level or index level of the model, the weights of elements that are pertained to one element are adopted, taking account of their deterioration degree. At the same time, the dam-age conditions of bridge are characterized by relative degree, element evaluation scale and structural technology mark of bridge ,so it agrees with Code for Maintenance of Highway Bridges and Culvers.

  17. Study on structural system of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Xigang; Pei Minshan; Yuan Hong; Xu Liping; Zhu Bin

    2009-01-01

    Sutong Bridge, whose layout is [ (100 + 100 + 300) + 1 088 + ( 300 + 100 + 100) ] m, marks the largest span of cable-stayed bridges in the world. The complex natural condition at the bridge site and the strict requirements for resistance of wind and seismic action make it crucial to choose a favorable structural system to assure the function and safety of the bridge. The comparison among several optional structural systems for Sutong Bridge is illustrated. After detailed analysis is carried out for viscous damper and hydraulic buffer, super liquid viscous damper with additional displacement limitation is designed for the first application in bridge engineering. The parameters for the damper is analyzed and studied and the dampers are installed suecessfuUy after quality tests.

  18. Bridge engineering handbook construction and maintenance

    CERN Document Server

    Chen, Wai-Fah

    2014-01-01

    Over 140 experts, 14 countries, and 89 chapters are represented in the second edition of the Bridge Engineering Handbook. This extensive collection highlights bridge engineering specimens from around the world, contains detailed information on bridge engineering, and thoroughly explains the concepts and practical applications surrounding the subject.Published in five books: Fundamentals, Superstructure Design, Substructure Design, Seismic Design, and Construction and Maintenance, this new edition provides numerous worked-out examples that give readers step-by-step design procedures, includes c

  19. Analysis of liquid bridge between spherical particles

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A pair of central moving spherical particles connected by a pendular liquid bridge with interstitial Newtonian fluid is often encountered in pariculate coalescence process. In this paper, by assuming perfect-wet condition, the effects of liquid volume and separation distance on static liquid bridge are analyzed, and the relation between rupture energy and liquid bridge volume is also studied. These points would be of significance in industrial processes related to adhesive particles.

  20. Bridge Engineering-Oriented Parametric Model

    Institute of Scientific and Technical Information of China (English)

    周凌远; 李乔

    2004-01-01

    A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a software system. This model provides both convenience and flexibility for users in structural modeling process. The object-oriented method is applied in the model implementation. A bridge analysis preprocessor is developed on the basis of this model. It provides an effective way for bridge modeling.

  1. Dynamics and Statics of Nonaxisymmetric Liquid Bridges

    Science.gov (United States)

    Alexander, J. Iwan D.; Resnick, Andrew H.; Slobozhanin, L. A.

    1996-01-01

    Theoretical and experimental investigation of the stability of nonaxisymmetric and nonaxisymmetric bridges contained between equal and unequal radii disks as a function of Bond and Weber number with emphasis on the transition from unstable axisymmetric to stable nonaxisymmetric shapes, are conducted. Numerical analysis of the stability of nonaxisymmetric bridges between unequal disks for various orientations of the gravity vector is performed. Experimental and theoretical investigation of large (nonaxisymmetric) oscillations and breaking of liquid bridges are also conducted.

  2. Mathematical Modelling of Bridges with SAP2000

    OpenAIRE

    Maraž, Miha

    2006-01-01

    The present work describes a relatively new programme module, which is enhanced in the recently released versions of SAP2000 software. The new module, called Bridge Modeler, is intended for simple, parametric mathematical modelling of bridges. The modelling procedure is explained on a test case through the steps of a user-friendly Bridge Wizard. For each step, we described the basic principles and the application possibilities as well as some limitations. We also explained two types of analys...

  3. Key Techniques for Design of Edong Changjiang River Highway Bridge%鄂东长江公路大桥设计关键技术

    Institute of Scientific and Technical Information of China (English)

    胡明义; 黄冰释; 余俊林; 唐守峰

    2011-01-01

    The main bridge of Edong Changjiang River Highway Bridge is a semi-floating system hybrid girder cable-stayed bridge with double pylons, double cable planes and with a main span 926 m. The main girder of the bridge was designed as the PK (Pasco-Kennewick Bridge) cross section of separated twin boxes, of which the part of the girder for the central span is of the steel box girder, the parts of the girder for the side spans are of the prestressed concrete (PC) box girders and a steel and concrete joint section was set on each side of the central span at a distance of 12. 5 m to the center of a pylon. To ensure a smooth transition between the steel and concrete structure, the multi-cell force transmission structure with PBL shear connectors was used for the joint section. The cable-to-pylon anchorage is the steel anchor box structure built in the column of a pylon. To control the development of concrete cracks in the anchorage zone in the pylon, the prestressing strands of 12φs 15. 24 were set in the concrete pylon wall on the side of the anchorage. To enhance the structural durability and service life, the durability of reinforced concrete and corrosion protection of steel structure were designed and the life cycle cost concept was applide to the design. The inspection and maintenance accesses for all principal components of the bridge were provided and the inspection and maintenance cycles, replacement criteria, workmanship and technical requirements were formulated as well.%鄂东长江公路大桥主桥为主跨926 m的双塔双索面半飘浮体系混合梁斜拉桥,主梁采用分离式双箱PK断面形式,中跨为钢箱梁,边跨为PC箱梁,钢-混凝土结合段设于中跨距桥塔中心12.5m处.为使钢结构与混凝土结构平稳过渡,钢-混凝土结合段采用PBL剪力连接器的多格室传力构造.索塔锚固采用在塔柱内置钢锚箱的构造,为控制锚固区混凝土裂缝开展,在锚固侧混凝土塔壁内设置12(o)s15.24预应力

  4. Buddha and the bridging relations.

    Science.gov (United States)

    Banerjee, Rahul

    2008-01-01

    The chapter reviews a classical Indian model of consciousness found in the Abhidhamma, a collection of seven treatises in the Pali Canon Tipitaka. The model was based on observations made during advanced vipassana practice, a first-person method taught by the Buddha. The climax of the model consists in the elucidation of 24 'Bridging Relations' causally linking the stream of consciousness, its contents and associated physical events. Review of such a model based on a specialized first-person technique could prove to be a resource of useful ideas providing directions for further research.

  5. Family Medicine: Bridge to Life.

    Science.gov (United States)

    Luz, Clare

    2016-01-01

    Reflecting on the suicide of a close friend, this essay explores what comprises, and inspires a will to live, and how those in Family Medicine can address suicide risk even in the face of debilitating or terminal illness. Research indicates that the will to live is a measurable indicator of general well-being, distinct from depression, and an important predictor of a person's motivation to "hold on to life". As such, understanding what is at the heart of a desire to live should alter clinical practice. This essay offers ideas for ways in which to create bridges for patients that could help sustain life.

  6. Nanoclusters a bridge across disciplines

    CERN Document Server

    Jena, Purusottam

    2010-01-01

    This comprehensive book on Nanoclusters comprises sixteen authoritative chapters written by leading researchers in the field. It provides insight into topics that are currently at the cutting edge of cluster science, with the main focus on metal and metal compound systems that are of particular interest in materials science, and also on aspects related to biology and medicine. While there are numerous books on clusters, the focus on clusters as a bridge across disciplines sets this book apart from others. Delivers cutting edge coverage of cluster science Covers a broad range of topics in

  7. A bridge to advanced mathematics

    CERN Document Server

    Sentilles, Dennis

    2011-01-01

    This helpful workbook-style ""bridge"" book introduces students to the foundations of advanced mathematics, spanning the gap between a practically oriented calculus sequence and subsequent courses in algebra and analysis with a more theoretical slant. Part 1 focuses on logic and number systems, providing the most basic tools, examples, and motivation for the manner, method, and concerns of higher mathematics. Part 2 covers sets, relations, functions, infinite sets, and mathematical proofs and reasoning. Author Dennis Sentilles also discusses the history and development of mathematics as well a

  8. Review of Energy Harvesters Utilizing Bridge Vibrations

    Directory of Open Access Journals (Sweden)

    Farid Ullah Khan

    2016-01-01

    Full Text Available For health monitoring of bridges, wireless acceleration sensor nodes (WASNs are normally used. In bridge environment, several forms of energy are available for operating WASNs that include wind, solar, acoustic, and vibration energy. However, only bridge vibration has the tendency to be utilized for embedded WASNs application in bridge structures. This paper reports on the recent advancements in the area of vibration energy harvesters (VEHs utilizing bridge oscillations. The bridge vibration is narrowband (1 to 40 Hz with low acceleration levels (0.01 to 3.8 g. For utilization of bridge vibration, electromagnetic based vibration energy harvesters (EM-VEHs and piezoelectric based vibration energy harvesters (PE-VEHs have been developed. The power generation of the reported EM-VEHs is in the range from 0.7 to 1450000 μW. However, the power production by the developed PE-VEHs ranges from 0.6 to 7700 μW. The overall size of most of the bridge VEHs is quite comparable and is in mesoscale. The resonant frequencies of EM-VEHs are on the lower side (0.13 to 27 Hz in comparison to PE-VEHs (1 to 120 Hz. The power densities reported for these bridge VEHs range from 0.01 to 9539.5 μW/cm3 and are quite enough to operate most of the commercial WASNs.

  9. CONDITION RATING SYSTEM FOR THAILAND'S CONCRETE BRIDGES

    Directory of Open Access Journals (Sweden)

    Bonaventure H.W. Hadikusumo

    2010-06-01

    Full Text Available The Bridge Management System is designed to maximise use of available data and determine the optimal strategy to perform necessary improvements to bridges in the most cost-effective manner. This paper provides a condition rating system to meet the requirements of Thailand’s Department of Highways (DOH. A rating system to assess the existing condition of bridges is proposed. Segmental inspection is developed to execute efficient element-level evaluations and collect data that demonstrate deterioration patterns in bridge elements. The paper also describes inspection procedures for field survey execution, which enables observed distresses at the level of sub-elements or members to be allocated. Recommendations from bridge experts reveal that the proposed rating system is robust, implementable in actual practice, and suitable for efficient application in evaluating the nation’s concrete highway bridges. Although the bridge condition rating was developed in response to the specific characteristics of Thailand’s bridges, the proposed methodology can easily be extended to other bridge agencies.

  10. A data management infrastructure for bridge monitoring

    Science.gov (United States)

    Jeong, Seongwoon; Byun, Jaewook; Kim, Daeyoung; Sohn, Hoon; Bae, In Hwan; Law, Kincho H.

    2015-04-01

    This paper discusses a data management infrastructure framework for bridge monitoring applications. As sensor technologies mature and become economically affordable, their deployment for bridge monitoring will continue to grow. Data management becomes a critical issue not only for storing the sensor data but also for integrating with the bridge model to support other functions, such as management, maintenance and inspection. The focus of this study is on the effective data management of bridge information and sensor data, which is crucial to structural health monitoring and life cycle management of bridge structures. We review the state-of-the-art of bridge information modeling and sensor data management, and propose a data management framework for bridge monitoring based on NoSQL database technologies that have been shown useful in handling high volume, time-series data and to flexibly deal with unstructured data schema. Specifically, Apache Cassandra and Mongo DB are deployed for the prototype implementation of the framework. This paper describes the database design for an XML-based Bridge Information Modeling (BrIM) schema, and the representation of sensor data using Sensor Model Language (SensorML). The proposed prototype data management framework is validated using data collected from the Yeongjong Bridge in Incheon, Korea.

  11. Assessment of the Reliability of Concrete Bridges

    DEFF Research Database (Denmark)

    Middleton, C. R.; Thoft-Christensen, Palle

    a significant shift in emphasis for the highways authorities around the world away from the design of new structures over to maintaining the existing infrastructure. As a result, bridge owners are seeking improved ways of inspecting, assessing, maintaining and repairing their existing stock of bridges...... in the wake of ever increasing traffic loads and volumes, and an ageing population of bridges subject to various mechanisms of deterioration. The goal is to optimise the allocation of limited resources whilst maintaining their bridges in a safe and serviceable condition. Reliability analysis is one tool being...

  12. Improved bone anchorage of hydroxypatite coated implants compared with tricalcium-phosphate coated implants in trabecular bone in dogs.

    Science.gov (United States)

    Lind, M; Overgaard, S; Bünger, C; Søballe, K

    1999-05-01

    Tricalcium phosphate (TCP) and hydroxyapatite (HA) ceramic coatings are bioactive coatings that have been shown to stimulate bone apposition onto ceramic-coated implants. TCP and HA ceramics have well-documented differences in physical properties, but both types of ceramics are used for stimulation of bone ongrowth to cementless endo-prosthetic components clinically. However, little is known about the difference in osteoconductive properties between these coatings when inserted into trabecular bone in a controlled experimental situation. Unloaded cylindrical gritblasted titanium (Ti-6A1-4V) implants (6 x 10 mm) coated with either hydroxyapatite (HA) or tricalcium phosphate (TCP) ceramic were inserted into the proximal humerus of 20 skeletally mature dogs. The implants were initially surrounded by a 2 mm gap. Each animal received one HA-coated implant and one TCP-coated implant. All dogs were sacrificed 6 weeks after surgery. Results were evaluated by histomorphometry and mechanical push-out test. Push-out tests demonstrated that HA-coated implants were 10-fold stronger fixated in comparison to TCP-coated implant. Bone ongrowth was significantly higher for HA-coated implants compared to TCP-coated implants. Bone volume in the gap showed a tendency to less bone volume around HA-coated implants compared to TCP-coated implants but this difference was insignificant. As expected almost all of the TCP coating were resorbed after 6 weeks and almost none of the HA coating. HA-coated implants with a grit-blasted surface provide a favorable early mechanical implant anchorage most likely due to superior ceramic stability compared to TCP-coated implants.

  13. CD45/CD11b Positive Subsets of Adult Lung Anchorage-Independent Cells Harness Epithelial Stem Cells

    Science.gov (United States)

    Peter, Yakov; Sen, Namita; Levantini, Elena; Keller, Steven; Ingenito, Edward P; Ciner, Aaron; Sackstein, Robert; Shapiro, Steven D

    2015-01-01

    Compensatory growth is mediated by multiple cell types that interact during organ repair. To elucidate the relationship between the stem/progenitor cells that proliferate or differentiate and the somatic cells of lung, we utilized a novel ex vivo pneumoexplant system. Applying this technique, we identified a sustained culture of repopulating adult progenitors in the form of free floating anchorage-independent cells (AICs). AICs did not express integrin proteins α5, β3, and β7, and constituted 37% of the total culture at day 14, yielding a mixed yet conserved population that recapitulated RNA expression patterns of the healthy lung. AICs exhibited rapid proliferation manifested by a marked 60-fold increase in cell numbers by day 21. Over 50% of the AIC population was cKit+ or double-positive for CD45+ and CD11b+ antigenic determinants, consistent with cells of hematopoietic origin. The latter subset was found to be enriched with prosurfactant protein-C and SCGB1A1 expressing putative stem cells and with aquaporin-5 producing cells, characteristic of terminally differentiated alveolar epithelial type-1 pneumocytes. AICs undergo remodeling to form a cellular lining at the air/gel interface, and TGFβ1 treatment modifies protein expression, implying direct-differentiation of this population. These data confirm the active participation of clonogenic hematopietic stem cells in a mammalian model of lung repair and validate mixed stem/somatic cell cultures, which embrace sustained cell viability, proliferation, and differentiation, for use in studies of compensatory pulmonary growth. PMID:22585451

  14. 23 CFR 650.409 - Evaluation of bridge inventory.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409... Evaluation of bridge inventory. (a) Sufficiency rating of bridges. Upon receipt and evaluation of the bridge inventory, a sufficiency rating will be assigned to each bridge by the Secretary in accordance with...

  15. 23 CFR 650.807 - Bridges requiring a USCG permit.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Bridges requiring a USCG permit. 650.807 Section 650.807... BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a USCG... improvement or construction of a bridge over navigable waters except for the exemption exercised by FHWA...

  16. 33 CFR 118.65 - Lights on fixed bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...

  17. 33 CFR 118.70 - Lights on swing bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on swing bridges. 118.70 Section 118.70 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.70 Lights on swing bridges. (a) Swing span lights on through bridges....

  18. 33 CFR 118.85 - Lights on vertical lift bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of...

  19. Finite element of multilayer surfacing systems on orthotropic steel bridges

    NARCIS (Netherlands)

    Li, J.; Liu, X.; Scarpas, A.; Tzimiris, G.

    2013-01-01

    Light weight orthotropic steel bridge decks have been widely utilized for bridges in seismic zones, movable bridges and long span bridges. In the last three decades, severe problems were reported in relation to asphaltic surfacing materials on orthotropic steel deck bridges. Earlier investigations h

  20. Light-weight aluminium bridges and bridge decks. An overview of recent applications

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Kluyver, D. de

    2008-01-01

    The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these pro

  1. The Bridge of Mandolin County

    Science.gov (United States)

    Lantz, Juliette M.; Feindt, Jenny E.; Lewellyn, Eric P. B.; Walczak, Mary M.

    1999-12-01

    The Bridge of Mandolin County is a case designed to teach the general chemistry principles of molar mass, ions and aqueous reactions, solubility rules, and inorganic nomenclature. Through the instructor-facilitated class discussion, students consider the options before the Mandolin Town Council regarding deicing the newly constructed bridge connecting Mandolin with a large nearby city. The students must decipher contradictory claims made on behalf of sodium chloride, the traditional deicer, and calcium magnesium acetate, a new environmentally friendly deicer, to arrive at the most cost-effective and environmentally appropriate deicing product. As they work through the analysis they raise questions that can be addressed in a laboratory setting. Four optional role-playing experiments are included, which can be used by the students to gather information helpful to resolution of the case. The case is intended to be used over two class periods, with a laboratory period in between, though suggestions for other models are provided. Laboratory procedures include an EDTA titration for Ca2+ and Mg2+, a gravimetric analysis, a qualitative examination of ions and solubility, an introduction to freezing point depression and measurement, and an experimental design activity. This case can also successfully be used without alteration in non-majors chemistry or environmental chemistry courses, or upper-level analytical or environmental chemistry courses.

  2. Global monitoring concept for bridges

    Science.gov (United States)

    Bergmeister, Konrad; Santa, Ulrich

    2000-06-01

    Knowledge of the integrity of in-service structures on a continuous time basis is an ultimate objective for owners and maintenance authorities. The development of a life extension and/or replacement strategy for highway structures is a crucial point in an effective bridge management system. A key component of such a bridge management system is a means of surveillance techniques and determining the condition of an existing structure within the normative and budgetary constraints. Recent advances in sensing technologies and material/structure damage characterization combined with current developments in computations and communications have resulted in a significant interest in developing diagnostic technologies for monitoring the integrity of and for the detection of damages of structures. To identify anomalies and deterioration processes, it is essential to understand the relationships between the signal measurements and the real occurred phenomena. Therefore, the comparison of measured and calculated data in order to tune and validate the mechanical and numerical model assumptions is an integral part of any system analysis. Finally, the interpreted results of all measurements should be the basis for the condition assessment and the safety evaluation of a structure to facilitate replacement and repair decisions.

  3. Bridging history and social psychology

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre; Yamamoto, Koji

    2012-01-01

    This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other’s work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social psycholog......This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other’s work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social...... psychologists can benefit from engaging with historical sources by being able to contextualise their findings and enrich their theoretical models. It is not only that all social and psychological phenomena have a history but this history is very much part of present-day and future developments. On the other...... hand historians can enhance their analysis of historical sources by drawing upon the conceptual tools developed in social psychology. They can “test” these tools and contribute to their validation and enrichment from completely different perspectives. Most important, as contributions to this special...

  4. Salt-bridge energetics in halophilic proteins.

    Directory of Open Access Journals (Sweden)

    Arnab Nayek

    Full Text Available Halophilic proteins have greater abundance of acidic over basic and very low bulky hydrophobic residues. Classical electrostatic stabilization was suggested as the key determinant for halophilic adaptation of protein. However, contribution of specific electrostatic interactions (i.e. salt-bridges to overall stability of halophilic proteins is yet to be understood. To understand this, we use Adaptive-Poison-Boltzmann-Solver Methods along with our home-built automation to workout net as well as associated component energy terms such as desolvation energy, bridge energy and background energy for 275 salt-bridges from 20 extremely halophilic proteins. We then perform extensive statistical analysis on general and energetic attributes on these salt-bridges. On average, 8 salt-bridges per 150 residues protein were observed which is almost twice than earlier report. Overall contributions of salt-bridges are -3.0 kcal mol-1. Majority (78% of salt-bridges in our dataset are stable and conserved in nature. Although, average contributions of component energy terms are equal, their individual details vary greatly from one another indicating their sensitivity to local micro-environment. Notably, 35% of salt-bridges in our database are buried and stable. Greater desolvation penalty of these buried salt-bridges are counteracted by stable network salt-bridges apart from favorable equal contributions of bridge and background terms. Recruitment of extensive network salt-bridges (46% with a net contribution of -5.0 kcal mol-1 per salt-bridge, seems to be a halophilic design wherein favorable average contribution of background term (-10 kcal mol-1 exceeds than that of bridge term (-7 kcal mol-1. Interiors of proteins from halophiles are seen to possess relatively higher abundance of charge and polar side chains than that of mesophiles which seems to be satisfied by cooperative network salt-bridges. Overall, our theoretical analyses provide insight into halophilic

  5. SHEAR LAG-DEBONDING MODEL FOR ANCHORAGE SECTION OF PRESTRESSED ANCHOR CABLE%预应力锚索锚固段的剪滞-脱黏模型

    Institute of Scientific and Technical Information of China (English)

    尤春安; 战玉宝; 刘秋媛; 孙琳琳; 王开彬

    2013-01-01

    Based on the calculating pattern of pulling prestressed anchorage body out from the base,the anchorage section can be divided into elastic region,plastic slide region and debonding region after analyzing the deformation and the damage process of the interface layer between anchorage body and grouting material,and the interfacial layer model for anchorage body and rock and soil mass is established.The theoretical solution of interfacial stress distribution was deduced by adopting the flow rule which associates with Coulomb condition.At the same time,a kind of new interface element model with properties of dilatancy and slippage is constructed; and interfacial stress distribution is calculated by two ways of numerical simulation and theoretical solution to verify the correctness of each other,so as to provide a new theoretical basis to calculate,analyze and design anchorage bodies.The results indicate that the main mechanical region is plastic slide region.So the plastic slippage state is the main state which the anchorage body usually in,so our researching and designing should be based on this state.In order to improve the anchoring force,we should improve maximum shear stress and extend the range of slip regime before the slip regime entering the debonding state.%基于预应力锚索锚固体从岩土体中拔出计算模式,通过锚固体与灌浆材料的界面界面层变形-破坏过程分析,将锚固段分为弹性区、塑性滑移区和脱黏区,建立锚固体-岩土体界面力学模型,采用与Coulomb条件关连的流动法则,导出界面应力分布的理论解;同时,构造具有剪胀和滑移特性的新型有限元界面单元,采用数值模拟的方法与界面应力分布的理论解进行相互验证,为锚固体受力的计算、分析与锚固体的设计提供理论依据.分析表明,锚固体的弹性区和脱黏区的受力较小,主要受力部分是塑性滑移区.因此,锚固体荷载的主要工况是塑性滑移状态,在研究

  6. Elevated p21-Activated Kinase 2 Activity Results in Anchorage-Independent Growth and Resistance to Anticancer Drug–Induced Cell Death

    Directory of Open Access Journals (Sweden)

    Jerry W. Marlin

    2009-03-01

    Full Text Available p21-Activated kinase 2 (PAK-2 seems to be a regulatory switch between cell survival and cell death signaling. We have shown previously that activation of full-length PAK-2 by Rac or Cdc42 stimulates cell survival, whereas caspase activation of PAK-2 to the proapoptotic PAK-2p34 fragment is involved in the cell death response. In this study, we present a role of elevated activity of full-length PAK-2 in anchorage-independent growth and resistance to anticancer drug–induced apoptosis of cancer cells. Hs578T human breast cancer cells that have low levels of PAK-2 activity were more sensitive to anticancer drug–induced apoptosis and showed higher levels of caspase activation of PAK-2 than MDA-MB435 and MCF-7 human breast cancer cells that have high levels of PAK-2 activity. To examine the role of elevated PAK-2 activity in breast cancer, we have introduced a conditionally active PAK-2 into Hs578T human breast cells. Conditional activation of PAK-2 causes loss of contact inhibition and anchorage-independent growth of Hs578T cells. Furthermore, conditional activation of PAK-2 suppresses activation of caspase 3, caspase activation of PAK-2, and apoptosis of Hs578T cells in response to the anticancer drug cisplatin. Our data suggest a novel mechanism by which full-length PAK-2 activity controls the apoptotic response by regulating levels of activated caspase 3 and thereby its own cleavage to the proapoptotic PAK-2p34 fragment. As a result, elevated PAK-2 activity interrupts the apoptotic response and thereby causes anchorage-independent survival and growth and resistance to anticancer drug–induced apoptosis.

  7. Orthodontic treatment of impacted teeth with implant anchorage%运用微型种植体支抗矫治埋伏阻生牙

    Institute of Scientific and Technical Information of China (English)

    张敏; 张立亚; 刘佳

    2011-01-01

    Objective To investigate effectiveness and efficiency of impacted teeth correction with implant anchorage.Methods Eight impacted teeth in six patients were corrected with implant anchorage after surgical exposure.Tooth mobility and pulp vitality were evaluated.Dental radiographs were taken before and after treatment.Results Good results were obtained and the impacted teeth were erupted within 3 ~ 5 months after orthodontic traction.The pulp of the teeth was vital Conclusions The implant anchorage could be used in the treatment of impacted teeth.%目的 初步分析运用种植支抗牵引埋伏牙的临床效果,探讨正畸治疗中选择种植支抗牵引埋伏牙的适应证及该项治疗的特点.方法 对6例埋伏牙患者的8颗埋伏牙运用种植支抗进行牵引治疗,牵引后对牙齿的松动度、牙髓活力等各项临床指标进行检查,并摄术前术后曲面断层片对牵引效果进行观察.结果 6例患者经3~5个月的牵引后埋伏牙萌出,牙髓活力正常,未发现牙根吸收.与以往的方法相比,运用种植支抗牵引埋伏牙支抗充足,患者不适感降低.结论 运用种植支抗牵引埋伏牙为埋伏牙牵引治疗提供了一种方法选择.

  8. 南京长江四桥有黏结预应力精细化施工质量控制技术%Quality Control Technology of Bonded Prestressed Precise Construction in Nanjing Yangtze River Fourth Bridge

    Institute of Scientific and Technical Information of China (English)

    濮卫; 郭正兴; 宗海; 刘家彬

    2011-01-01

    In the 1980s and 1990s, the main work content of prestressed engineering quality control were controlling the steel strand quality and improving the anchorage equality in China. During the 21 st century,principal target in domestic engineering field was enhancing the durability of the prestressed concrete structure. In the background of main bridge and approach bridge in connecting engineering of Nanjing Yangtze River Fourth Bridge, the paper detailedly introduced the quality control technology in precise construction of bonded prestressed engineering, which ensured the durability of prestressed concrete bridge.%我国预应力工程质量控制,20世纪八九十年代以控制钢绞线质量和提高锚具质量为主要工作内容.进入21世纪后,提高预应力混凝土结构的耐久性成为国内工程领域新的主攻目标.以南京长江第四大桥接线工程主线桥及引桥为工程背景,详细介绍了有黏结预应力工程的精细化施工质量控制技术,保证了预应力混凝土桥梁的耐久性.

  9. Ankylosed maxillary incisor with severe root resorption treated with a single-tooth dento-osseous osteotomy, vertical alveolar distraction osteogenesis, and mini-implant anchorage.

    Science.gov (United States)

    Senışık, Neslihan Ebru; Koçer, Gülperi; Kaya, Bulem Üreyen

    2014-09-01

    Dentoalveolar ankylosis interferes with the vertical growth of the alveolar process, which can lead to an open bite, an unesthetic smile, and occlusal disharmony. This case report presents a new treatment protocol for an ankylosed tooth with severe root resorption using a combined surgical orthodontic management protocol involving a single-tooth dento-osseous osteotomy and vertical alveolar distraction osteogenesis with intraoral elastics and mini-implant anchorage. After distraction and active orthodontic treatment, the patient's anterior open bite was corrected. A Class I dental relationship was achieved, overjet was decreased, and a normal incisor relationship was obtained.

  10. Thermal Pollution Mathematical Model. Volume 6: Verification of Three-Dimensional Free-Surface Model at Anclote Anchorage. [environment impact of thermal discharges from power plants

    Science.gov (United States)

    Lee, S. S.; Sengupta, S.; Tuann, S. Y.; Lee, C. R.

    1980-01-01

    The free-surface model presented is for tidal estuaries and coastal regions where ambient tidal forces play an important role in the dispersal of heated water. The model is time dependent, three dimensional, and can handle irregular bottom topography. The vertical stretching coordinate is adopted for better treatment of kinematic condition at the water surface. The results include surface elevation, velocity, and temperature. The model was verified at the Anclote Anchorage site of Florida Power Company. Two data bases at four tidal stages for winter and summer conditions were used to verify the model. Differences between measured and predicted temperatures are on an average of less than 1 C.

  11. A Statistical Observation of Crowns and Bridges in 1988 Part 2 : Bridge

    OpenAIRE

    小林, 賢一; 小坂, 茂; 柳田, 史城; 稲生, 衡樹; 大島, 俊明; 高橋, 喜博; 岩井, 啓三; 甘利, 光治; 中根, 卓

    1991-01-01

    A study was made of 207 bridges which had been fabricated for patients at the Prosthodontic Clinic of Matsumoto Dental College during 1988. Some of results were as follows; 1) 47.3% of the patients were males and 52.7% were females. 2) 92.8% of the patients were between 20 and 69 years old. 3) 65.2%of the bridges were fabricated as 3-unit bridges. 4) 77.8% were fabricated as 1-pontic bridges. 5) There were fewer bridge retainers for the lower anterior segment than for other segments. 6) 52.3%...

  12. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    the results obtained using the numerical models given in details in "Heavy Vehicles on Minor Highway Bridges : dynamic modelling of vehicles and bridges". The models are established using a ordinary vehicle which consists of a 48 t Scania with a 3 axle tractor and a 3 axle trailer, joined in a flexible hinge...

  13. Passing the Einstein-Rosen bridge

    CERN Document Server

    Katanaev, M O

    2013-01-01

    We relax the requirement of geodesic completeness of a space-time. Instead, we require test particles trajectories to be smooth only in the physical sector. Test particles trajectories for Einstein--Rosen bridge are proved to be smooth in the physical sector, and particles can freely penetrate the bridge in both directions.

  14. COUPLING VIBRATION OF VEHICLE-BRIDGE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    陈炎; 黄小清; 马友发

    2004-01-01

    By applying the sinusoidal wave mode to simulate the rugged surface of bridge deck,accounting for vehicle-bridge interaction and using Euler-Bernoulli beam theory, a coupling vibration model of vehicle-bridge system was developed. The model was solved by mode analyzing method and Runge-Kutta method, and the dynamic response and the resonance curve of the bridge were obtained. It is found that there are two resonance regions, one represents the main resonance while the other the minor resonance, in the resonance curve. The influence due to the rugged surface, the vibration mode of bridge, and the interaction between vehicle and bridge on vibration of the system were discussed. Numerical results show that the influence due to these parameters is so significant that the effect of roughness of the bridge deck and the mode shape of the bridge can't be ignored and the vehicle velocity should be kept away from the critical speed of the vehicle.

  15. Active aerodynamic stabilisation of long suspension bridges

    DEFF Research Database (Denmark)

    Nissen, Henrik Ditlev; Sørensen, Paul Haase; Jannerup, Ole Erik

    2004-01-01

    The paper describes the addition of actively controlled appendages (flaps) attached along the length of the bridge deck to dampen wind-induced oscillations in long suppension bridges. A novel approach using control systems methods for the analysis of dynamic stability is presented. In order to ma...

  16. General framework for bridge life cycle design

    Institute of Scientific and Technical Information of China (English)

    Junhai MA; Airong CHEN; Jun HE

    2009-01-01

    Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environ-mental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.

  17. Re-Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper two aspects of re-assessment of the reliability of concrete bridges are discussed namely modelling of the corrosion of reinforcement and updating of uncertain variables. The main reason for deterioration of concrete bridges is corrosion of the reinforcement. Therefore, modelling...

  18. Lifetime Reliability Assessment of Concrete Slab Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    A procedure for lifetime assesment of the reliability of short concrete slab bridges is presented in the paper. Corrosion of the reinforcement is the deterioration mechanism used for estimating the reliability profiles for such bridges. The importance of using sensitivity measures is stressed. Fi...

  19. Precast Pearl-Chain concrete arch bridges

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

    2015-01-01

    A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post-tensioning......, and gives a large positive bending moment below the load and a smaller negative bending moment in the unloaded side. When the Pearl-Chain Bridge concept is compared to other pre-fabricated arch bridge solutions we find a number of advantages when using Pearl-Chain Bridges: Straight elements, combination...

  20. Effects of the earthquake of March 27, 1964, on the Eklutna Hydroelectric Project, Anchorage, Alaska, with a section on television examination of earthquake damage to underground communication and electrical systems in Anchorage: Chapter A in The Alaska earthquake, March 27, 1964: effects on transportation, communications, and utilities

    Science.gov (United States)

    Logan, Malcolm H.; with a section on Television Examination of Earthquake Damage to Underground Communication and Electrical Systems in Anchorage by Burton, Lynn R.

    1967-01-01

    The March 27, 1964, Alaska earthquake and its associated aftershocks caused damage requiring several million dollars worth of repair to the Eklwtna Hydroelectric Project, 34 miles northeast of Anchorage. Electric service from the Eklutna powerplant was interrupted during the early phase of the March 27 earthquake, built was restored (intermittently) until May 9,1964, when the plant was closed for inspection and repair. Water for Eklutna project is transported from Eklutna Lake to the powerplant at tidewater on Knik Arm of Cook Inlet by an underwater intake connected to a 4.46-mile tunnel penstock. The primary damage caused by the earthquake was 1at the intake structure in Eklutna Lake. No damage to the power tunnel was observed. The piles-supported powerplant and appurtenant structures, Anchorage and Palmer substations, and the transmission lines suffered minor dammage. Most damage occurred to facilities constructed on un-consolidated sediments and overburden which densified and subsided during the earthquake. Structures built on bedrock experienced little or no damage. Underground communication and electrical systems in Anchorage were examined with a small-diameter television camera to locate damaged areas requiring repair. Most of the damage was concentrated at or near valley slopes. Those parts of the systems within the major slide areas of the city were destroyed.

  1. The I-35W bridge Project Website

    DEFF Research Database (Denmark)

    Kampf, Constance

    How can websites be used to rebuild trust?  In August 2007, the Interstate Highway 35-W bridge in Minneapolis, MN collapsed during rush hour.  Although many people were rescued and casualties were as limited as could be expected due to quick and effective intervention, the image of a major bridge...... collapsing during rush hour damaged the Minnesota Department of Transportation's reputation and resulted in the loss of public trust for the organization.  The ensuing bridge reconstruction project included a project website intended to rebuild this trust through transparency, community involvement......, and the use of multimodal features.  This paper looks at the I35-W bridge reconstruction project in Minneapolis through web-based communication by the Minnesota Department of Transportation (MnDOT) about the project. The MnDOT bridge reconstruction website will be examined using a combination of 1). Weick...

  2. Seismic response of steel suspension bridge

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, D.B. [Lawrence Livermore National Lab., CA (United States); Astaneh-Asl, A. [California Univ., Berkeley, CA (United States). Dept. of Civil and Environmental Engineering

    1996-11-01

    Performing accurate, realistic numerical simulations of the seismic response of long-span bridges presents a significant challenge to the fields of earthquake engineering and seismology. Suspension bridges in particular represent some of the largest and most important man-made structures and ensuring the seismic integrity of these mega-structures is contingent on accurate estimations of earthquake ground motions and accurate computational simulations of the structure/foundation system response. A cooperative, multi-year research project between the Univ. of California and LLNL was recently initiated to study engineering and seismological issues essential for simulating the response of major structures. Part of this research project is focused on the response of the long-span bridges with the San Francisco-Oakland Bay Bridge serving as a case study. This paper reports on the status of this multi-disciplinary research project with emphasis on the numerical simulation of the transient seismic response of the Bay Bridge.

  3. Optimum Maintenance Strategies for Highway Bridges

    DEFF Research Database (Denmark)

    Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.;

    As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

  4. Building bridges … and accelerators

    CERN Multimedia

    2009-01-01

    Lyn Evans, the LHC project leader, was awarded an honorary doctorate from the University of Geneva (UNIGE) to celebrate his role not just in building accelerators, but also in building bridges between nations. He was one of four notables honoured at the event on Friday 5 June, coinciding with the University’s 450th Anniversary. Lyn Evans arriving at the ceremony with Archbishop Desmond Tutu. "It was a big surprise when I found out I’d been nominated," recounts Evans, "but it was an even bigger surprise to find out with whom I’d been nominated". At the ceremony Evans was awarded the honorary doctorate along with three others: Archbishop Desmond Tutu, who was acclaimed for his fight against apartheid in South Africa, Mary Robinson, first woman president of Ireland and former United Nations’ high commissioner of human rights, and Pascal Lamy, Director-General of the World Trade Organization. The award ceremony, known as the �...

  5. Treatment of Class II malocclusion with bialveolar protrusion by means of unusual extractions and anchorage mini-implant

    Directory of Open Access Journals (Sweden)

    Jong-Moon Chae

    2012-10-01

    Full Text Available INTRODUCTION: Patients with dental Class II bialveolar protrusion are generally treated by extracting the four first premolars or two first and two second premolars, and retracting the anterior teeth. This case report describes the treatment of an adult patient with bialveolar protrusion, a Class II canine and molar relationship, and lip protrusion. METHODS: In this patient, the maxillary right second molar (1.7 had to be extracted due to extensive caries. To create sufficient space to retract the anterior teeth, the maxillary right posterior teeth were distalized with a maxillary posterior mini-implant (1.2~1.3 mm in diameter, 10 mm long, which was placed into the maxillary tuberosity area and allowed an en masse retraction of the maxillary anterior teeth. RESULTS: Overall, mini-implant can provide anchorage to produce a good facial profile even without additional premolar extraction in cases of dental Class II bialveolar protrusion with the hopeless second molar. CONCLUSION: The total treatment period was 42 months and the results were acceptable for 34 months after debonding.INTRODUÇÃO: os pacientes com Classe II e biprotrusão alveolar são, geralmente, tratados com extração de quatro primeiros pré-molares ou dois primeiros e dois segundos pré-molares, e retração dos dentes anteriores. Este relato de caso descreve o tratamento de um paciente adulto com biprotrusão alveolar, relação de caninos e de molares em Classe II e protrusão labial. MÉTODOS: nesse paciente, o segundo molar superior direito precisou ser extraído devido a cáries extensas. Para criar espaço suficiente para retração dos dentes anteriores, os dentes posterossuperiores direitos foram distalizados com um mini-implante posterossuperior (1,2 ~ 1,3mm de diâmetro, 10mm de comprimento, que foi colocado na área da tuberosidade maxilar e permitiu uma retração em massa dos dentes anteriores. RESULTADOS: em geral, mini-implantes podem fornecer ancoragem para

  6. 口周肌力在下颌支抗控制中的临床应用研究%Clinical application of perioral muscular forces in mandibular anchorage control

    Institute of Scientific and Technical Information of China (English)

    林汤毅; 许衍; 王震东; 李强

    2011-01-01

    目的 探讨口周肌力在下颌支抗控制中的应用.方法 临床上应用多曲不锈钢丝唇挡配合方丝弓固定矫治器对13例恒牙早期轻度牙列拥挤患者进行矫治,分析治疗前后支抗磨牙位置变化,观察支抗丧失情况.结果 利用口周肌力可以对支抗磨牙进行控制,防止支抗丧失.结论 可以在矫治过程中采用多曲唇挡来增强支抗.而且多曲唇挡制作简单,患者戴用舒适、隐蔽,容易获得患者的配合.%Objective To study the application of perioral muscular forces in the mandibular anchorage control in order to search a new approach of increasing the intro-oral anchorage. Methods Thirteen patients with mild crowding in permanent dentition were treated with edgewise appliance and multiloop lip bumper. The movement of anchorage molar in before and after treatment was recorded so as to observe the loss of anchorage. Results The loss of anchorage could be avoided through the application of perioral muscular forces. Conclusions The multiloop lip bumper can be applied to increase anchorage, which is easily fabricated, comfortable and hidden for patients.

  7. Classically activated macrophages promote anchorage-dependent and anchorage-independent clone formation of breast cancer cells%经典激活巨噬细胞促进乳腺癌细胞贴壁和非贴壁克隆形成

    Institute of Scientific and Technical Information of China (English)

    陈静琦; 朱必胜; 侯开连

    2013-01-01

    目的 探讨经典激活巨噬细胞(M1)对乳腺癌细胞贴壁和非贴壁克隆形成的影响,进一步阐明M1促乳腺癌进展的作用.方法 用密度梯度离心法,从健康成人外周血中分离单个核细胞,体外诱导M1.在乳腺癌细胞与巨噬细胞的无血清共培养体系中,做平板克隆实验;在M1-乳腺癌细胞软琼脂培养体系中,做非贴壁克隆形成实验,检测M1对乳腺癌贴壁克隆和非贴壁克隆形成的影响.结果 在M1的作用下,乳腺癌SK-3rd细胞贴壁克隆和非贴壁克隆形成的能力均增强(P<0.001).结论 M1促进乳腺癌细胞贴壁克隆和非贴壁克隆的形成.%Objective To investigate the effect of activated microphages (M1) on the clone formation of breast cancer cells.Methods Mononuclear cells were isolated from peripheral blood of adult normal subjects by density gradient centrifugation,and M1 was induced in vitro.In the serum-free co-culture system of breast cancer cells and macrophages,the fiat cloning assay was performed and in soft agar culture system of Ml-breast cancer cells,anchorage-independent clone formation assay was performed.Results The anchorage-dependent and anchorage-independent clone formation of SK-3rd breast cancer cells was induced by M1 (P < 0.001).Conclusion M1 promotes anchorage-dependent and anchorage-independent clone formation of breast cancer cells.

  8. Di-Ethylhexylphthalate (DEHP Modulates Cell Invasion, Migration and Anchorage Independent Growth through Targeting S100P in LN-229 Glioblastoma Cells

    Directory of Open Access Journals (Sweden)

    Jennifer Nicole Sims

    2014-05-01

    Full Text Available Glioblastoma multiforme (GBM is the most aggressive brain cancer with a median survival of 1–2 years. The treatment of GBM includes surgical resection, radiation and chemotherapy, which minimally extends survival. This poor prognosis necessitates the identification of novel molecular targets associated with glioblastoma. S100P is associated with drug resistance, metastasis, and poor clinical outcomes in many malignancies. The functional role of S100P in glioblastoma has not been fully investigated. In this study, we examined the role of S100P mediating the effects of the environmental contaminant, DEHP, in glioblastoma cells (LN-229 by assessing cell proliferation, apoptosis, anchorage independent growth, cell migration and invasion following DEHP exposure. Silencing S100P and DEHP treatment inhibited LN-229 glioblastoma cell proliferation and induced apoptosis. Anchorage independent growth study revealed significantly decreased colony formation in shS100P cells. We also observed reduced cell migration in cells treated with DEHP following S100P knockdown. Similar results were observed in spheroid formation and expansion. This study is the first to demonstrate the effects of DEHP on glioblastoma cells, and implicates S100P as a potential therapeutic target that may be useful as a drug response biomarker.

  9. A role for Mfb1p in region-specific anchorage of high-functioning mitochondria and lifespan in Saccharomyces cerevisiae.

    Science.gov (United States)

    Pernice, Wolfgang M; Vevea, Jason D; Pon, Liza A

    2016-02-03

    Previous studies indicate that replicative lifespan in daughter cells of Sacchraromyces cerevisiae depends on the preferential inheritance of young, high-functioning mitochondria. We report here that mitochondria are functionally segregated even within single mother cells in S. cerevisiae. A high-functioning population of mitochondria accumulates at the tip of the mother cell distal to the bud. We find that the mitochondrial F-box protein (Mfb1p) localizes to mitochondria in the mother tip and is required for mitochondrial anchorage at that site, independent of the previously identified anchorage protein Num1p. Deletion of MFB1 results in loss of the mother-tip-localized mitochondrial population, defects in mitochondrial function and premature replicative ageing. Inhibiting mitochondrial inheritance to buds, by deletion of MMR1, in mfb1Δ cells restores mitochondrial distribution, promotes mitochondrial function and extends replicative lifespan. Our results identify a mechanism that retains a reservoir of high-functioning mitochondria in mother cells and thereby preserves maternal reproductive capacity.

  10. Oscillations in a sunspot with light bridges

    CERN Document Server

    Yuan, Ding; Huang, Zhenghua; Li, Bo; Su, Jiangtao; Yan, Yihua; Tan, Baolin

    2014-01-01

    Solar Optical Telescope onboard Hinode observed a sunspot (AR 11836) with two light bridges (LBs) on 31 Aug 2013. We analysed a 2-hour \\ion{Ca}{2} H emission intensity data set and detected strong 5-min oscillation power on both LBs and in the inner penumbra. The time-distance plot reveals that 5-min oscillation phase does not vary significantly along the thin bridge, indicating that the oscillations are likely to originate from the underneath. The slit taken along the central axis of the wide light bridge exhibits a standing wave feature. However, at the centre of the wide bridge, the 5-min oscillation power is found to be stronger than at its sides. Moreover, the time-distance plot across the wide bridge exhibits a herringbone pattern that indicates a counter-stream of two running waves originated at the bridge sides. Thus, the 5-min oscillations on the wide bridge also resemble the properties of running penumbral waves. The 5-min oscillations are suppressed in the umbra, while the 3-min oscillations occupy...

  11. Signal and noise in bridging PCR

    Directory of Open Access Journals (Sweden)

    Thaler David S

    2002-07-01

    Full Text Available Abstract Background In a variant of the standard PCR reaction termed bridging, or jumping, PCR the primer-bound sequences are originally on separate template molecules. Bridging can occur if, and only if, the templates contain a region of sequence similarity. A 3' end of synthesis in one round of synthesis that terminates in this region of similarity can prime on the other. In principle, Bridging PCR (BPCR can detect a subpopulation of one template that terminates synthesis in the region of sequence shared by the other template. This study considers the sensitivity and noise of BPCR as a quantitative assay for backbone interruptions. Bridging synthesis is also important to some methods for computing with DNA. Results In this study, BPCR was tested over a 328 base pair segment of the E. coli lac operon and a signal to noise ratio (S/N of approximately 10 was obtained under normal PCR conditions with Taq polymerase. With special precautions in the case of Taq or by using the Stoffel fragment the S/N was improved to 100, i.e. 1 part of cut input DNA yielded the same output as 100 parts of intact input DNA. Conclusions In the E. coli lac operator region studied here, depending on details of protocol, between 3 and 30% per kilobase of final PCR product resulted from bridging. Other systems are expected to differ in the proportion of product that is bridged consequent to PCR protocol and the sequence analyzed. In many cases physical bridging during PCR will have no informational consequence because the bridged templates are of identical sequence, but in a number of special cases bridging creates, or, destroys, information.

  12. Design of Concrete Self-Anchored Suspension Bridge of Wusong Bridge in Jilin City%吉林市雾凇大桥混凝土自锚式悬索桥设计

    Institute of Scientific and Technical Information of China (English)

    张伟; 唐贺强; 宁伯伟

    2011-01-01

    The main bridge of the Wusong Bridge in Jilin City is a 5-span continuous concrete self-anchored suspension bridge with span arrangement (35+68+150+68+35) m. A summarized account of the design and calculation of the main bridge is presented herewith. On the bridge, the transverse and vertical bearings and the longitudinal dampers are arranged in between the stiffening girder and towers. The girder is of a concrete 3-cell single box section, the depth of a typical segment of the girder is 2.5 m and towards the anchorage sections at the side spans, the segments of the girder gradually change into a depth of 6.5 m. A tower of the bridge is a concrete portal frame structure that is 54 m in height and the tower columns and the cross beams on the towers are all of rectangular hollow sections. Beneath a tower pier are the pile caps of separation type and each pile cap is supported by 9 nos. of Φ2.0 m bored piles. The main cables are respectively made up of Φ5.1 mm galvanized high strength steel wires and the hanger cables are of Φ7.0 mm low relaxation galvanized high strength parallel steel wires. In the design, the finite element software MIDAS Civil 2006, the nonlinear analysis software BNLAS for suspension bridge and the plane program SCDS are employed to calculate and analyze the bridge. The results of the calculation and analysis indicate that all checking calculation made for the bridge can conform to the relevant requirements in the codes.%吉林市雾凇大桥主桥为(35+68+150+68+35)m五跨连续混凝土自锚式悬索桥,综述该桥主桥设计与计算.该桥塔梁间设置横、竖向支座和纵向阻尼器;加劲梁采用单箱三室混凝土截面,标准段梁高2.5 m,在边跨锚固段渐变至6.5 m;桥塔采用门形框架混凝土结构,高54 m,塔身及横梁均采用矩形空心截面;桥塔墩下部采用分离式承台,单个承台布置9根φ2.0 m钻孔灌注桩;主缆采用φ5.1 mm镀锌高强钢丝,吊索采用φ7.0 mm低松弛镀锌高强

  13. 异型钢箱混凝土索塔锚固区空间力学行为研究%Spatial Mechanical Behavior Research of Cable-pylon Anchorage Zone of Steel Box Concrete Tower

    Institute of Scientific and Technical Information of China (English)

    党栋; 贺拴海; 赵煜; 李世安

    2012-01-01

    In order to grasp the force performance and stress distribution of shaped pylon steel anchor box under the action of the cable tension, with a main span of 555 m length of three towers cable-stayed and self-anchored suspension combined system bridge as the engineering background, through the ANSYS APDL command stream parametric programming, the different finite element models of pylon steel anchor box is established by the spatial solid element and shell element, the mechanical properties of cable-pylon anchorage zone were studied under the most unfavorable load combination, considering the stress state and distribution characteristics of steel anchor box under different orthodontic force. The results showed that;under the most unfavorable combination of loads, the stress was concentrated at the position of the anchor plate and pressure plate using the initial strain mode; the calculation results of solid element and shell element were consistent by uniform loading mode, which could reflect the real stress state of steel anchor box, but the shell element corner contact area prone to stress calculation distortion. The results provide the basis for the design and have some design reference value for the design of the same type bridge.%为了掌握异型索塔钢锚箱在索力作用下的受力性能和应力分布,以某主跨555 m 长的三塔斜拉-自锚式悬索组合体系桥为工程背景,通过 ANSYS 中 APDL 命令流参数化编程,分别采用空间实体单元与壳单元建立了不同的索塔钢锚箱有限元模型,对索塔锚固区在最不利荷载组合作用下的受力性能进行了研究,并考虑了在不同加力方式下钢锚箱应力状态和分布特点.结果表明:在最不利荷载组合作用下,采用初应变加力方式,在锚垫板与承压板位置处应力较集中;采用均布力加载方式下,实体单元与壳单元计算结果较为吻合,能真实反映钢锚箱受力状态,但壳单元角点接触部位易出现应

  14. Building the clinical bridge: an Australian success.

    Science.gov (United States)

    Wallis, Marianne; Chaboyer, Wendy

    2012-01-01

    Nursing effectiveness science includes primary, secondary, and translational, clinically focused research activities which aim to improve patient or client outcomes. It is imperative, for the successful conduct of a program of nursing effectiveness science, that a clinical bridge is established between academic and healthcare service facilities. An Australian example of the development of a robust clinical bridge through the use of jointly funded positions at the professorial level is outlined. In addition, an analysis of the practical application of Lewin's model of change management and the contribution of both servant and transformational leadership styles to the bridge building process is provided.

  15. Building the Clinical Bridge: An Australian Success

    Directory of Open Access Journals (Sweden)

    Marianne Wallis

    2012-01-01

    Full Text Available Nursing effectiveness science includes primary, secondary, and translational, clinically focused research activities which aim to improve patient or client outcomes. It is imperative, for the successful conduct of a program of nursing effectiveness science, that a clinical bridge is established between academic and healthcare service facilities. An Australian example of the development of a robust clinical bridge through the use of jointly funded positions at the professorial level is outlined. In addition, an analysis of the practical application of Lewin’s model of change management and the contribution of both servant and transformational leadership styles to the bridge building process is provided.

  16. Asymptotics of a horizontal liquid bridge

    Science.gov (United States)

    Haynes, M.; O'Brien, S. B. G.; Benilov, E. S.

    2016-04-01

    This paper uses asymptotic techniques to find the shape of a two dimensional liquid bridge suspended between two vertical walls. We model the equilibrium bridge shape using the Laplace-Young equation. We use the Bond number as a small parameter to deduce an asymptotic solution which is then compared with numerical solutions. The perturbation approach demonstrates that equilibrium is only possible if the contact angle lies within a hysteresis interval and the analysis relates the width of this interval to the Bond number. This result is verified by comparison with a global force balance. In addition, we examine the quasi-static evolution of such a two dimensional bridge.

  17. Calculations in bridge aeroelasticity via CFD

    Energy Technology Data Exchange (ETDEWEB)

    Brar, P.S.; Raul, R.; Scanlan, R.H. [Johns Hopkins Univ., Baltimore, MD (United States)

    1996-12-31

    The central focus of the present study is the numerical calculation of flutter derivatives. These aeroelastic coefficients play an important role in determining the stability or instability of long, flexible structures under ambient wind loading. A class of Civil Engineering structures most susceptible to such an instability are long-span bridges of the cable-stayed or suspended-span variety. The disastrous collapse of the Tacoma Narrows suspension bridge in the recent past, due to a flutter instability, has been a big impetus in motivating studies in flutter of bridge decks.

  18. Gust loading on streamlined bridge decks

    DEFF Research Database (Denmark)

    Larose, Guy; Mann, Jakob

    1998-01-01

    The current analytical description of the buffeting action of wind on long-span bridges is based on the strip assumption. However, recent experiments on closed-box girder bridge decks have shown that this assumption is not valid and is the source of an important part of the error margin...... of the analytical prediction methods. In this paper, an analytical model that departs from the strip assumption is used to describe the gust loading on a thin airfoil. A parallel is drawn between the analytical model and direct measurements of gust loading on motionless closed-box girder bridge decks. Empirical...

  19. Transformation of the bridge during drop separation

    Science.gov (United States)

    Chashechkin, Yu. D.; Prokhorov, V. E.

    2016-05-01

    The geometry of flows during separation of pendant drops of liquids with significantly different physical properties (alcohol, water, glycerin, oil) has been studied by high-speed video recording. The dynamics of the processes involving the formation of bridges of two characteristic shapes—slightly nonuniform in thickness and with thinning of the upper and lower ends—has been investigated. It has been shown that the shape change of the separated bridge has a number of stages determined by the properties of the liquid. As a result, the bridge is transformed into a small drop—a satellite drop.

  20. Closure technique for the hybrid girder cable stayed bridge of Edong Bridge

    Institute of Scientific and Technical Information of China (English)

    Liu Minghu; Tan Hao; Xu GuoPing; Zhao Canhui

    2012-01-01

    Based on Edong Yangtze River Bridge, which is the second longest hybrid girder cable stayed bridge with 926 m long main span, the influencing factors and crucial techniques of the main span closure method for long span hybrid girder cable stayed bridge are studied. After theoretical analysis, numerical evaluation and practical test, the loading assistant closure method is employed in Edong Yangtze River Bridge. The loading assistant closure method, with better thermal adaptability and less influence on bridge line and the forced status, can meet the requirements of the unstressed state control method. Based on the mentioned advantages, the loading assistant closure method is applicable to long span hybrid girder cable stayed bridges. The conclusion can provide a reference for the further design of the similar brid~es.

  1. Diode-quad bridge circuit means

    Science.gov (United States)

    Harrison, D. R.; Dimeff, J. (Inventor)

    1975-01-01

    A transducer and frequency discriminator circuit is described including a four-terminal circulating diode bridge, a first pair of capacitors connected in series across two terminals of the bridge, and a second pair of capacitors, or other impedance elements, connected in series across the other two terminals of the bridge. A source of balanced alternating electrical energy for energizing the circuit is coupled between the commonly connected plates of the first pair of capacitors and the commonly connected plates of the second pair of capacitors. Due to the operation of the diode bridge, the sum of the resultant charges developed on the first pair of capacitors is proportional to the relationship between the respective capacitors of the second pair, and consequently, an output voltage taken across the first pair of capacitors will be proportional to that relationship.

  2. Allegheny County-Owned Bridges Points

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the location of bridges owned by Allegheny County as centroids. If viewing this description on the Western Pennsylvania Regional Data Center’s...

  3. Allegheny County-Owned Bridges Centerlines

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the bridges owned by Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  4. Relaxation of liquid bridge after droplets coalescence

    Directory of Open Access Journals (Sweden)

    Jiangen Zheng

    2016-11-01

    Full Text Available We investigate the relaxation of liquid bridge after the coalescence of two sessile droplets resting on an organic glass substrate both experimentally and theoretically. The liquid bridge is found to relax to its equilibrium shape via two distinct approaches: damped oscillation relaxation and underdamped relaxation. When the viscosity is low, damped oscillation shows up, in this approach, the liquid bridge undergoes a damped oscillation process until it reaches its stable shape. However, if the viscous effects become significant, underdamped relaxation occurs. In this case, the liquid bridge relaxes to its equilibrium state in a non-periodic decay mode. In depth analysis indicates that the damping rate and oscillation period of damped oscillation are related to an inertial-capillary time scale τc. These experimental results are also testified by our numerical simulations with COMSOL Multiphysics.

  5. Wheatstone bridge technique for magnetostriction measurements.

    Science.gov (United States)

    Sullivan, M

    1980-03-01

    A basic Wheatstone bridge, with additional electronic instrumentation, has been used in the measurement of magnetostriction. This method allows a resolution of approximately 10% on measurements of magnetostrictions less than 0.75 parts per million.

  6. VT Short Structures - Bridges and Culverts

    Data.gov (United States)

    Vermont Center for Geographic Information — Inspection data for structures (bridge and culvert) between 6 feet and 20 feet in length inspected on State road system. Stewards: Information Technology, Data...

  7. VT Long Structures - Bridges and Culverts

    Data.gov (United States)

    Vermont Center for Geographic Information — Inspection data for structures (bridge and culvert) greater than 20 feet in length inspected on both State and local road systems. Stewards: Information Technology,...

  8. Active Control of Long Bridges Using Flaps

    DEFF Research Database (Denmark)

    Hansen, H. I.; Thoft-Christensen, Palle

    The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap...... is the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for different flap...... configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

  9. Pilot testing of a hydraulic bridge exciter

    Directory of Open Access Journals (Sweden)

    Andersson Andreas

    2015-01-01

    Full Text Available This paper describes the development of a hydraulic bridge exciter and its first pilot testing on a full scale railway bridge in service. The exciter is based on a hydraulic load cylinder with a capacity of 50 kN and is intended for controlled dynamic loading up to at least 50 Hz. The load is applied from underneath the bridge, enabling testing while the railway line is in service. The system is shown to produce constant load amplitude even at resonance. The exciter is used to experimentally determine frequency response functions at all sensor locations, which serve as valuable input for model updating and verification. An FE-model of the case study bridge has been developed that is in good agreement with the experimental results.

  10. Practical Approach to Fragility Analysis of Bridges

    Directory of Open Access Journals (Sweden)

    Yasamin Rafie Nazari

    2012-12-01

    Full Text Available Damages during past earthquakes reveal seismic vulnerability of bridge structures and the necessity of probabilistic approach toward seismic performance evaluation of bridges and its interpretation in terms of decision variables such as repair cost, downtime and life loss. This Procedure involves hazard analysis, structural analysis, damage analysis and loss analysis. The purpose of present study is reviewing different methods developed to derive fragility curves for damage analysis of bridges and demonstrating a simple procedure for fragility analysis using Microsoft Office Excel worksheet to reach probability of occurring predefined level of damage due to different levels of seismic demand parameters. The input of this procedure is the intensity of ground motion and the output is an appropriate estimate of the expected damage. Different observed damages of the bridges are discussed and compared the practical definition of damage states. Different methods of fragility analyses are discussed and a practical step by step example is illustrated.

  11. Identifying hidden sexual bridging communities in Chicago.

    Science.gov (United States)

    Youm, Yoosik; Mackesy-Amiti, Mary Ellen; Williams, Chyvette T; Ouellet, Lawrence J

    2009-07-01

    Bridge populations can play a central role in the spread of human immunodeficiency virus (HIV) by providing transmission links between higher and lower prevalence populations. While social network methods are well suited to the study of bridge populations, analyses tend to focus on dyads (i.e., risk between drug and/or sex partners) and ignore bridges between distinct subpopulations. This study takes initial steps toward moving the analysis of sexual network linkages beyond individual and risk group levels to a community level in which Chicago's 77 community areas are examined as subpopulations for the purpose of identifying potential bridging communities. Of particular interest are "hidden" bridging communities; that is, areas with above-average levels of sexual ties with other areas but whose below-average AIDS prevalence may hide their potential importance for HIV prevention. Data for this analysis came from the first wave of recruiting at the Chicago Sexual Acquisition and Transmission of HIV Cooperative Agreement Program site. Between August 2005 through October 2006, respondent-driven sampling was used to recruit users of heroin, cocaine, or methamphetamine, men who have sex with men regardless of drug use, the sex partners of these two groups, and sex partners of the sex partners. In this cross-sectional study of the sexual transmission of HIV, participants completed a network-focused computer-assisted self-administered interview, which included questions about the geographic locations of sexual contacts with up to six recent partners. Bridging scores for each area were determined using a matrix representing Chicago's 77 community areas and were assessed using two measures: non-redundant ties and flow betweenness. Bridging measures and acquired immunodeficiency syndrome (AIDS) case prevalence rates were plotted for each community area on charts representing four conditions: below-average bridging and AIDS prevalence, below-average bridging and above

  12. 49 CFR 237.33 - Content of bridge management programs.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Content of bridge management programs. 237.33... Content of bridge management programs. Each bridge management program adopted in compliance with this part... spans, span lengths, and all other information necessary to provide for the management of bridge...

  13. 23 CFR 650.705 - Application for discretionary bridge funds.

    Science.gov (United States)

    2010-04-01

    ... TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650... cost, current average daily truck traffic and a narrative describing the existing bridge, the proposed new or rehabilitated bridge and other relevant factors which the State believes may warrant...

  14. 33 CFR 118.80 - Lights on bascule bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on bascule bridges. 118.80 Section 118.80 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.80 Lights on bascule bridges. (a) Lift span lights. Each lift span...

  15. 33 CFR 118.90 - Bridges crossing channel obliquely.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bridges crossing channel obliquely. 118.90 Section 118.90 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges crossing channel obliquely....

  16. 23 CFR 650.809 - Movable span bridges.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Movable span bridges. 650.809 Section 650.809 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span bridges. A fixed...

  17. Detection of salt bridges to lysines in solution in barnase

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Williamson, Michael P.; Hounslow, Andrea M.

    2013-01-01

    We show that salt bridges involving lysines can be detected by deuterium isotope effects on NMR chemical shifts of the sidechain amine. Lys27 in the ribonuclease barnase is salt bridged, and mutation of Arg69 to Lys retains a partially buried salt bridge. The salt bridges are functionally important....

  18. Inspection Based Evaluation of a Danish Road Bridge

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper it is shown how an inspection-based evaluation of a Danish road bridge may be performed using the BRIDGE1 and BRIDGE2 bridge management systems produced within the EC-supported research programme "Assessment of Performance and Optimal Strategies for Inspection and Maintenance...

  19. Micromechanical model of cross-over fibre bridging - Prediction of mixed mode bridging laws

    DEFF Research Database (Denmark)

    Sørensen, Bent F.; Gamstedt, E.K.; Østergaard, Rasmus Christian;

    2008-01-01

    on the observed bridging mechanism, a micromechanical model is developed for the prediction of macroscopic mixed mode bridging laws (stress-opening laws). The model predicts a high normal stress for very small openings, decreasing rapidly with increasing normal and tangential crack opening displacements......The fracture resistance of fibre composites can be greatly enhanced by crack bridging. In situ observations of mixed mode crack growth in a unidirectional carbon-fibre/epoxy composite reveal crack bridging by single fibres and by beam-like ligaments consisting of several fibres. Based...

  20. Thermal Bridge Effects in Walls Separating Rowhouses

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    In this report the thermal bridge effects at internal wall/roof junctions in rowhouses are evaluated. The analysis is performed using a numerical calculation programme, and different solutions are evaluated with respect to extra heat loss and internal surface temperatures.......In this report the thermal bridge effects at internal wall/roof junctions in rowhouses are evaluated. The analysis is performed using a numerical calculation programme, and different solutions are evaluated with respect to extra heat loss and internal surface temperatures....

  1. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Kirkegaard, Poul Henning; Enevoldsen, I.

    The present paper worked out as a part of a research project on "Dynamic amplification factor of vehicle loadings on smaller bridges" establishes a two-dimensional spectral description of the road roughness surface based on measurements from a Danish road using so-called Profilograph used by Danish...... to the bridge and the stochastic nature of the surface roughness are included into the model....

  2. Earthquake Resistance of Integral Abutment Bridges

    OpenAIRE

    2009-01-01

    intermediate length bridges. Integral abutment construction eliminates joints and bearings which reduce long-term maintenance costs. However, in the absence of joints and bearings, the bridge abutments and foundations must be able to accommodate lateral movements from thermal expansion and contraction of the superstructure and from seismic events. Previous research has focused on the response to thermal expansion and contraction. The current research examines the response of integral abutment...

  3. Arch bridges – unlocking their potential

    OpenAIRE

    Long, Adrian; Nanukuttan, Sreejith

    2016-01-01

    Arch bridges are strong, durable, aesthetically pleasing and require little maintenance but very few have been built since the early 1900s. However, this trend has changed as more than 60 FlexiArch bridges have been installed since the system was launched in 2007. The FlexiArch uses precast concrete voussoirs, requires neither corrodible reinforcement, nor centring, can be installed in hours and is contractor friendly. Details of this innovative method of construction and installation of arch...

  4. External Prestressing Bridge Reinforcement Technology Review

    Directory of Open Access Journals (Sweden)

    Zhu Hanbing

    2015-01-01

    Full Text Available Externally prestressed bridge can not only limit and reduce the cracks and deformation of the structure, improve the rigidity and bearing capacity of structure, improve the stress state of structure, but also have less interference for bridge operation when it is operating and have the good economic efficiency. This paper introduces the advantages and disadvantages of external prestressed strengthening technique, its calculation theory and construction technology described in detail, and finally the paper discusses the deficiency of existing research.

  5. Framework for Bridges Maintenance in Egypt

    Directory of Open Access Journals (Sweden)

    Hesham Abd Elkhalek

    2016-01-01

    Full Text Available The traditional approaches for bridges maintenance is proven to be inefficient as they lead to random way of spending maintenance budget and deteriorating bridge conditions. In many cases, maintenance activities are performed due to user complaints. The objective of this paper is to develop a practical and reliable framework to manage the maintenance and repair activities of Bridges network in Egypt considering performance and budget limits. The model solves an optimization problem that maximizes the average condition of the network given the limited budget using Genetic Algorithm (GA. The main tasks of the system are bridge inventory, condition assessment, deterioration using markov model, and maintenance optimization. The developed model takes into account multiple parameters including serviceability requirements, budget allocation, element importance on structural safety and serviceability, bridge impact on network, and traffic. A questionnaire is conducted to complete the research scope. The proposed model is implemented in software, which provides a friendly user interface. The results of the framework are multi – year maintenance plan for the entire network for up to five years. A case study is presented for validating and testing the model with Data collected from “General Authority for Roads, Bridges and Land Transport” in Egypt.

  6. I-5/Gilman advanced technology bridge project

    Science.gov (United States)

    Lanza di Scalea, Francesco; Karbhari, Vistasp M.; Seible, Frieder

    2000-04-01

    The UCSD led I-5/Gilman Advanced Technology Bridge Project will design and construct a fully functional traffic bridge of advanced composite materials across Interstate 5 in La Jolla, California. Its objective is to demonstrate the use of advanced composite technologies developed by the aerospace industry in commercial applications to increase the life expectancy of new structures and for the rehabilitation of aging infrastructure components. The structure will be a 450 ft long, 60 ft wide cable-stayed bridge supported by a 150 ft A-frame pylon with two vehicular lanes, two bicycle lanes, pedestrian walkways and utility tunnels. The longitudinal girders and pylon will be carbon fiber shells filled with concrete. The transverse deck system will consist of hollow glass/carbon hybrid tubes and a polypropylene fiber reinforced concrete deck with an arch action. Selected cables will be composite. The bridge's structural behavior will be monitored to determine how advanced composite materials perform in civil infrastructure applications. The bridge will be instrumented to obtain performance and structural health data in real time and, where possible, in a remote fashion. The sensors applied to the bridge will include electrical resistance strain gages, fiberoptic Bragg gratings and accelerometers.

  7. Clinical research of orthopedic treatment with implant anchorage in orthodontics%种植支抗在口腔正畸治疗中的临床研究

    Institute of Scientific and Technical Information of China (English)

    李茜; 王军

    2011-01-01

    目的:分析研究种植支抗在口腔正畸治疗中的临床应用情况.方法:回顾性分析2009年1月-2010年1月期间在我院治疗的34例需种植义齿修复同时件错合畸形的患者;或者常规支抗缺乏或不理想的错合畸形的成年患者的临床资料.结果:应用Branemark种植体在牙列缺损律错合畸形患者的缺失牙医植入,以此为种植支抗对34例错合畸形患者进行了治疗.34例患者全部顺利完成治疗,而且种植体无明显松动,34例患者经畸形矫正和义齿修复后获得满意效果.结论:种植支抗能够应用于需种植义齿修复同时件错合畸形的患者,且对口颌系统无不良作用,有较好的临床效果.%Objective: To the clinical research of orthopedic treatment with implant anchorage in orthodontics. Methods: A retrospective analysis a-bout clinical data treatment with 34 patients who required implant restoration at the same time pieces of malocclusion patients and lack of conventional anchorage or unsatisfactory malocclusion in January from 2009 to2010 in our hospital. Results! Application of Branemark implants in the dentition defect with malocclusion in patients who missing teeth implants, the 34 patients with malocclusion were treated on this implant. The whole patients completed treatment successfully without implant loosening. Have obtained satisfactory results. Conclusion: implant anchorage can be used to plant the same time pieces of malocclusion patients,and the corresponding jaw system without adverse effects, have better clinical results.

  8. 深基坑锚固工程中成孔技术%Bore-making Technique in the Anchorage Project of Deep Foundation Pit

    Institute of Scientific and Technical Information of China (English)

    曾庆辉

    2001-01-01

    Impact Spiral Drilling is a new bore-making techni que. Its usage in the anchorage project of deep foundation ditch can solve the p roblem of drilling in the soft and hard cross stratum. In this article, the auth or specially introduces the structure of impact spiral drill machine and its ope ration techniques.%冲击螺旋钻孔是一种新的成孔工艺,在深基坑的锚固技术中成功地解决了软硬互层、夹杂地层的钻进。本文详细介绍了冲击螺旋钻的构造和成孔操作技术。

  9. A Tale of Five Bridges; the use of GNSS for Monitoring the Deflections of Bridges

    Science.gov (United States)

    Roberts, Gethin Wyn; Brown, Christopher J.; Tang, Xu; Meng, Xiaolin; Ogundipe, Oluropo

    2014-11-01

    The first Bridge Monitoring surveying was carried out in 1996 by the authors, through attaching Ashtech ZXII GPS receivers onto the Humber Bridge' parapet, and gathering and further analysing the resulting 1 Hz RTK GPS data. Various surveys have subsequently been conducted on the Humber Bridge, the Millennium Bridge, the Forth Road Bridge, the Severn Suspension Bridge and the Avonmouth Viaduct. These were all carried out using survey grade carrier phase/pseudorange GPS and later GNSS receivers. These receivers were primarily dual frequency receivers, but the work has also investigated the use of single frequency receivers, gathering data at 1 Hz, 10 Hz, 20 Hz and even 100 Hz. Various aspects of the research conducted are reported here, as well as the historical approach. Conclusions are shown in the paper, as well as lessons learnt during the development of this work. The results are compared to various models that exist of the bridges' movements, and compare well. The results also illustrate that calculating the frequencies of the movements, as well as looking at the magnitudes of the movements, is an important aspect of this work. It is also shown that in instances where the magnitudes of the movements of the bridge under investigation are small, it is still possible to derive very accurate frequencies of the movements, in comparison to the existing models.

  10. Role of multiprotein bridging factor 1 in archaea: bridging the domains?

    NARCIS (Netherlands)

    Koning, de B.; Blombach, F.; Wu Hao,; Brouns, S.J.J.; Oost, van der J.

    2009-01-01

    MBF1 (multiprotein bridging factor 1) is a highly conserved protein in archaea and eukaryotes. It was originally identified as a mediator of the eukaryotic transcription regulator BmFTZ-F1 (Bombyx mori regulator of fushi tarazu). MBF1 was demonstrated to enhance transcription by forming a bridge bet

  11. Outcomes and stability in patients with anterior open bite and long anterior face height treated with temporary anchorage devices and a maxillary intrusion splint

    Science.gov (United States)

    Scheffler, Nicole R.; Proffit, William R.; Phillips, Ceib

    2015-01-01

    Introduction Temporary skeletal anchorage devices now offer the possibility of closing anterior open bites and decreasing anterior face height by intruding maxillary posterior teeth, but data for treatment outcomes are lacking. This article presents outcomes and posttreatment changes for consecutive patients treated with a standardized technique. Methods The sample included 33 consecutive patients who had intrusion of maxillary posterior teeth with a maxillary occlusal splint and nickel-titanium coil springs to temporary anchorage devices in the zygomatic buttress area, buccal and apical to the maxillary molars. Of this group, 30 had adequate cephalograms available for the period of treatment, 27 had cephalograms including 1-year posttreatment, and 25 had cephalograms from 2 years or longer. Results During splint therapy, the mean molar intrusion was 2.3 mm. The mean decrease in anterior face height was 1.6 mm, less than expected because of a 0.6-mm mean eruption of the mandibular molars. During the postintrusion orthodontics, the mean change in maxillary molar position was a 0.2-mm extrusion, and there was a mean 0.5-mm increase in face height. Positive overbite was maintained in all patients, with a slight elongation (<2 mm) of the incisors contributing to this. During the 1 year of posttreatment retention, the mean changes were a further eruption of 0.5 mm of the maxillary molars, whereas the mandibular molars intruded by 0.6 mm, and there was a small decrease in anterior face height. Changes beyond 1 year posttreatment were small and attributable to growth rather than relapse in tooth positions. Conclusions Intrusion of the maxillary posterior teeth can give satisfactory correction of moderately severe anterior open bites, but 0.5 to 1.5 mm of reeruption of these teeth is likely to occur. Controlling the vertical position of the mandibular molars so that they do not erupt as the maxillary teeth are intruded is important in obtaining a decrease in face height

  12. Conditions of Proper Interaction of Low-Pressure Injection Piles (LIP) with Structure and Soil, Carrying Capacity of Pile Anchorage in Foundation

    Science.gov (United States)

    Pachla, Henryk

    2016-12-01

    The formation of a pile in the existing foundation and soil creates a new foundation construction which has a structure of foundation-pile-soil. This construction must be able to transfer loads from the foundation to the pile and from the pile to the soil. The pile structure has to transfer an imposed load. From the point of view of continuum mechanics determination of the capacity of such a system is preceded by the analysis of contact problem of three contact surfaces. Each of these surfaces is determined by different pairs of materials. The pair which creates a pile anchorage is a material from which the foundation is built (structure of stone and grout, brick and grout, concrete or reinforced concrete and grout. The pile structure is formed by grout and steel rebar. The pile formed in soil is created by a pair of grout and soil. What is important is that on contact surfaces the materials adhering to one another are subjected to different deformation types that are controlled by mechanical properties and geometry of these surfaces. In the paper, additional conditions that should be fulfilled for the foundation-pile-soil system to make load transfer from foundation to soil possible and safe are presented. The results of research done by the author on foundation-pile contact surface are discussed. The tests were targeted at verifying the bearing capacity of anchorage and deformation of piles made of grout and other materials from which foundations are built. The specimens were tested in tension and compression. The experiments were conducted on the amount specimens which is regarded as small sample to enable the statistical analysis of the results.

  13. Natural vibration dynamics of Rainbow Bridge, Utah

    Science.gov (United States)

    Moore, J. R.; Thorne, M. S.; Wood, J. R.; Doyle, S.; Stanfield, E.; White, B.

    2015-12-01

    We measured resonant frequencies of Rainbow Bridge, Utah, one of the world's longest rock spans, during a field experiment recording ambient vibration data. Measurements were generated over 20 hours on March 23-24, 2015 using two broadband three-component seismometers placed on the bridge, and compared to concurrent data from nearby reference stations 20 and 220 m distant. We identified seven distinct modes of vibration for Rainbow Bridge between 1 and 6 Hz. Data for each resonant frequency was then analyzed to determine the frequency-dependent polarization vector in an attempt to clarify mode shapes; e.g. the fundamental mode represents out-of-plane horizontal flexure. We compared experimental data to results of 3D numerical modal analysis, using a new photogrammetric model of Rainbow Bridge generated in this study imported into COMSOL Multiphysics. Results compare well with measured data for seven of the first eight modeled modes, matching vibrational frequencies and polarization orientations generally within 10%. Only predicted mode 6 was not explicitly apparent in our experimental data. Large site-to-reference spectral ratios resolved from experimental data indicate high amplification on the bridge as compared to nearby bedrock.

  14. A probabilistic bridge safety evaluation against floods.

    Science.gov (United States)

    Liao, Kuo-Wei; Muto, Yasunori; Chen, Wei-Lun; Wu, Bang-Ho

    2016-01-01

    To further capture the influences of uncertain factors on river bridge safety evaluation, a probabilistic approach is adopted. Because this is a systematic and nonlinear problem, MPP-based reliability analyses are not suitable. A sampling approach such as a Monte Carlo simulation (MCS) or importance sampling is often adopted. To enhance the efficiency of the sampling approach, this study utilizes Bayesian least squares support vector machines to construct a response surface followed by an MCS, providing a more precise safety index. Although there are several factors impacting the flood-resistant reliability of a bridge, previous experiences and studies show that the reliability of the bridge itself plays a key role. Thus, the goal of this study is to analyze the system reliability of a selected bridge that includes five limit states. The random variables considered here include the water surface elevation, water velocity, local scour depth, soil property and wind load. Because the first three variables are deeply affected by river hydraulics, a probabilistic HEC-RAS-based simulation is performed to capture the uncertainties in those random variables. The accuracy and variation of our solutions are confirmed by a direct MCS to ensure the applicability of the proposed approach. The results of a numerical example indicate that the proposed approach can efficiently provide an accurate bridge safety evaluation and maintain satisfactory variation.

  15. Using rotating liquid bridges as accelerometers

    Energy Technology Data Exchange (ETDEWEB)

    Montanero, J.M. [Universidad de Extremadura, Badajoz (Spain). Dept. de Electronica e Ingenieria Electromecanica; Cabezas, G.; Acero, J.; Zayas, F.

    1999-07-01

    Liquid bridges have recently been proposed as fluid accelerometers that could be used to measure very small inertial forces under microgravity conditions [Meseguer et al., microgravity sci. technol. IX/2 (1996)]. The essential idea is to infer the values of such inertial forces from the liquid bridge interface contour, whose shape obviously depends on the values of such forces (apart from the bridge volume and the geometry of the supporting disks). Following a similar procedure, in this paper we explore the use of rotating axisymmetric liquid bridges to measure the residual axial gravity and the rotation rate of the liquid bridge regarded as a solid body. In light off the difficulties involved in performing experiments on Earth, the role of empirical data is played by an accurate numerical solution of the Young-Laplace equation. The values of both the axial gravity and angular speed are obtained by fitting the approximate analytical expressions derived in this paper to the numerical solution of the Young-Laplace equation. The comparison between the predicted and actual values of the variables of interest shows a satisfactory agreement, supporting the suitability of the procedure. (orig.)

  16. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    of heavier trucks moving at larger speeds, and partly because the authorities want to permit transportation of special heavy goods at a larger part of the road net. These needs will in many cases cause the strengthening of the bridges becomes necessary. In order to keep the expenses of such strengthening...... projects at a minimum, it is necessary to perform accurate estimates of the dynamic amplification factor (defined as the dynamic load effect divided by the static load effect from the vehicles), so this quantity is neither over- nor underestimated. The principal aims of the present paper are to establish...... the numerical models for the mathematical models of the vehicles and the bridge from which the load amplification factors can be estimated assuming that the dynamic parameters of the vehicles and the modal parameters of the bridge are known....

  17. Ergonomic aspects of automation in navigation bridges.

    Science.gov (United States)

    Lazet, A; Walraven, P L

    1971-06-01

    New ergonomic questions arise from the tendency toward increasing automation in maritime operations. Direct control of engines and rudder from the bridge promises improved ship control, provided that the operator can really exploit the technical improvements. To make such direct control most efficient, good ergonomic design is essential. A series of designs of navigation bridges is used to illustrate typical problems and situations. The building of full scale mock-ups of complete bridges is essential in order to handle the design as an integrated problem and to simulate the work situation. Such static mock-ups have been shown to be extremely useful in the discussion between builder, future user and adviser. An extension to dynamic simulation is necessary in order to study the actual work conditions in a new design.

  18. Influence of Icing on Bridge Cable Aerodynamics

    DEFF Research Database (Denmark)

    Koss, Holger; Frej Henningsen, Jesper; Olsen, Idar

    2013-01-01

    In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -5......°C may lead to large amplitude vibrations of bridge cables under wind action. For the prediction of aerodynamic instability quasi-steady models have been developed estimating the cable response magnitude based on structural properties and aerodynamic force coefficients for drag, lift and torsion....... The determination of these force coefficients require a proper simulation of the ice layer occurring under the specific climatic conditions, favouring real ice accretion over simplified artificial reproduction. The work presented in this paper was performed to study the influence of ice accretion on the aerodynamic...

  19. Stability of dynamic response of suspension bridges

    Science.gov (United States)

    Capsoni, Antonio; Ardito, Raffaele; Guerrieri, Andrea

    2017-04-01

    The potential occurrence of internal parametric resonance phenomena has been recently indicated as a potential contributory cause of the appearance of critical dynamic states in long-span suspension bridges. At the same time, suspension bridges, in view of their flexibility, are prone to aeroelastic response, such as vortex shedding, torsional divergence and flutter. In this paper, a non-linear dynamic model of a suspension bridge is devised, with the purpose of providing a first attempt toward a unified framework for the study of aeroelastic and internal resonance instabilities. Inspired by the pioneering work of Herrmann and Hauger, the analyses have been based on a linearized formulation that is able to represent the main structural non-linear effects and the coupling given by aerodynamic forces. The results confirm that the interaction between aeroelastic effects and non-linear internal resonance leads to unstable conditions for wind speeds which can be lower than the critical threshold for standard aeroelastic predictions.

  20. Building bridges within the bacterial chromosome.

    Science.gov (United States)

    Song, Dan; Loparo, Joseph J

    2015-03-01

    All organisms must dramatically compact their genomes to accommodate DNA within the cell. Bacteria use a set of DNA-binding proteins with low sequence specificity called nucleoid-associated proteins (NAPs) to assist in chromosome condensation and organization. By bending or bridging DNA, NAPs also facilitate chromosome segregation and regulate gene expression. Over the past decade, emerging single-molecule and chromosome conformation capture techniques have investigated the molecular mechanisms by which NAPs remodel and organize the bacterial chromosome. In this review we describe how such approaches reveal the biochemical mechanisms of three NAPs that are believed to facilitate DNA bridging: histone-like nucleoid structuring protein (H-NS), ParB, and structural maintenance of chromosomes (SMC). These three proteins form qualitatively different DNA bridges, leading to varied effects on transcription and chromosome segregation.

  1. Fast Hough transform for automatic bridge extraction

    Science.gov (United States)

    Hao, Qiwei; Chen, Xiaomei; Ni, Guoqiang; Zhang, Huaili

    2008-03-01

    In this paper, a new method to recognize bridge in the complicated background is presented. The algorithm takes full advantages of the characteristics of the bridge image. Firstly, the image is preprocessed and the object edges are extracted. Then according to the limitations of traditional Hough transform (HT), the extraction method of the image line segment characteristic of HT is improved, which eliminates spurious peaks on the basis of global and local thresholds, discriminates the position relation between two straight line segments, and merges segments with near endpoints, etc. Experiments show that this algorithm is more precise and efficient than traditional HT, moreover it can provide a complete description of the bridge in a complicated background.

  2. MINERAL BRIDGES OF NACRE AND ITS EFFECTS

    Institute of Scientific and Technical Information of China (English)

    宋凡; 白以龙

    2001-01-01

    Nacre, or mother-of-pearl, is a kind of composites of aragonite platelets sandwiched between organic materials. Its excellent mechanical properties are thought to stem from the microarchitecture that is traditionally described as a "brick and mortar" arrangement. In this paper, a new microstructure, referred to as mineral bridge in the biomineralization, is directly observed in the organic matrix layers (mortar) of nacre. This is an indication that the organic matrix layer of nacre should be treated as a three-dimensional interface and the microarchitecture of nacre ought to be considered as a "brick-bridge-mortar" structure rather than the traditional one. Experiments and analyses show that the mineral bridges not only improve the mechanical properties of the organic matrix layers but also play an important role in the pattern of the crack extension in nacre.

  3. Operational modal analysis of road-rail bridge

    OpenAIRE

    Cardoso M.; Sampaio R. A. C.; de Souza R. M.; Silva E.

    2015-01-01

    In this paper, we describe an Operational Modal Analysis (OMA) of the Bridge over the Tocantins River, a composite road-rail bridge located in the city of Marabá, state of Pará, northern Brazil. The bridge is part of the Carajás Railway, which is used by VALE Company to transport iron ore from “Serra dos Carajás”, the largest mineral reserve of the planet. The bridge has a length of 2310m, being the second longest road-rail bridge in Brazil. The study focused on the bridge central span (with ...

  4. Dragon bridge - the world largest dragon-shaped (ARCH steel bridge as element of smart city

    Directory of Open Access Journals (Sweden)

    Chinh Luong Minh

    2016-01-01

    Full Text Available Dragon Bridge - The world’s largest dragon-shaped steel bridge, with an installation cost of $85 million USD, features 6 lanes for two separate directions, 666 meters of undulating steel in the shape of a dragon in the Ly Dynasty, the symbol of prosperity in Vietnamese culture. This unique and beautifully lit bridge, which also breathes fire and sprays water. It’s the purposeful integration of the lighting hardware articulates the dragon’s form, and the fire-breathing dragon head. This project transcends the notion of monumental bridge with dynamic colour-changing lighting, creating an iconic sculpture in the skyline that is both reverent and whimsical. The signature feature of the bridge was the massive undulating support structure resembling a dragon flying over the river. The dragon is prominent in Vietnamese culture as a symbol of power and nobility. Dragon Bridge stands out as a model of innovation. It has received worldwide attention in the design community and from the global media for its unique arch support system. Dragon Bridge serves as an example of how aesthetic quality of a design can serve cultural, economic and functional purposes. The article presents design solutions of the object and the evaluation of the technical condition before putting the facility into service.

  5. The seismic response of concrete arch bridges (with focus on the Bixby Creek bridge Carmel, California)

    Energy Technology Data Exchange (ETDEWEB)

    Hoehler, M; McCallen, D; Noble, C

    1999-06-01

    The analysis, and subsequent retrofit, of concrete arch bridges during recent years has relied heavily on the use of computational simulation. For seismic analysis in particular, computer simulation, typically utilizing linear approximations of structural behavior, has become standard practice. This report presents the results of a comprehensive study of the significance of model sophistication (i.e. linear vs. nonlinear) and pertinent modeling assumptions on the dynamic response of concrete arch bridges. The study uses the Bixby Creek Bridge, located in California, as a case study. In addition to presenting general recommendations for analysis of this class of structures, this report provides an independent evaluation of the proposed seismic retrofit for the Bixby Creek Bridge. Results from the study clearly illustrate a reduction of displacement drifts and redistribution of member forces brought on by the inclusion of material nonlinearity. The analyses demonstrate that accurate modeling of expansion joints, for the Bixby Creek Bridge in particular, is critical to achieve representative modal and transient behavior. The inclusion of near-field displacement pulses in ground motion records was shown to significantly increase demand on the relatively softer, longer period Bixby Creek Bridge arch. Stiffer, shorter period arches, however, are more likely susceptible to variable support motions arising from the canyon topography typical for this class of bridges.

  6. Extracorporeal Life Support Bridge to Ventricular Assist Device: The Double Bridge Strategy.

    Science.gov (United States)

    Marasco, Silvana F; Lo, Casey; Murphy, Deirdre; Summerhayes, Robyn; Quayle, Margaret; Zimmet, Adam; Bailey, Michael

    2016-01-01

    In patients requiring left ventricular assist device (LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support (ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device (VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre-LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre-VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these "crash and burn" patients.

  7. Stability of a liquid bridge under vibration

    Science.gov (United States)

    Benilov, E. S.

    2016-06-01

    We examine the stability of a vertical liquid bridge between two vertically vibrating, coaxial disks. Assuming that the vibration amplitude and period are much smaller than the mean distance between the disks and the global timescale, respectively, we employ the method of multiple scales to derive a set of asymptotic equations. The set is then used to examine the stability of a bridge of an almost cylindrical shape. It is shown that, if acting alone, gravity is a destabilizing influence, whereas vibration can weaken it or even eliminate altogether. Thus, counter-intuitively, vibration can stabilize an otherwise unstable capillary structure.

  8. A Bridge Deflection Monitoring with GPS

    Science.gov (United States)

    Figurski, M.; Gałuszkiewicz, M.; Wrona, M.

    2007-01-01

    This paper introduces results of investigation carried on by The Applied Geomatics Section in Military University of Technology. Research includes possibilities of monitoring dynamic behavior of a bridge using high rate GPS data. Whole event was executed with collaboration of The Road and Bridge Management and The Warsaw Geodesy Company. Interdisciplinary approach with this project allows authors to get reliable information about investigating constructions and their respond for true traffic loading detected by GPS receivers. Way of compute data and used software (TRACK) are also shown in this paper.

  9. Planar Hall effect bridge magnetic field sensors

    DEFF Research Database (Denmark)

    Henriksen, A.D.; Dalslet, Bjarke Thomas; Skieller, D.H.

    2010-01-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can...... be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar...... Hall effect bridge sensors....

  10. Analysis of Biaxially Stressed Bridge Deck Plates

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Bondum, Tommi Højer

    2012-01-01

    The ultimate state analysis of bridge deck plates at the intersection zone between main girders and transverse beams is complicated by biaxial membrane stresses, which may be in compression or tension in either direction depending on the bridge configuration and the specific location. This paper...... presents a detailed investigation of the ultimate capacity of simply supported plates subjected to biaxial loads. The full interaction domain of combinations of compressive and tensile loads has been investigated including a large number of imperfections. It was found that non-standard imperfection modes...

  11. Construction Technology of Long Span Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    2000-01-01

    A large variety of construction methods are used during construction of major bridges, and in many cases the final structural system must be chosen with due respect to the construction process. Today the preferred construction methods are: the free-cantilever method, the launching method and the ......A large variety of construction methods are used during construction of major bridges, and in many cases the final structural system must be chosen with due respect to the construction process. Today the preferred construction methods are: the free-cantilever method, the launching method...

  12. Ambient Vibration Test on Reinforced Concrete Bridges

    Directory of Open Access Journals (Sweden)

    Idris Nurul Shazwin

    2016-01-01

    Full Text Available An investigation was carried out to determine dynamic characteristic of reinforced concrete (RC bridges by using ambient vibration test (AVT. The ambient vibration sources on bridges may come from traffic, wind, wave motion and seismic events. AVT describes the dynamic characteristics of the bridge and ground by measuring the natural frequencies using highly sensitive seismometer sensor. This test is beneficial due to light weight equipment and smaller number of operator required, cheap and easy to be handled. It is able to give a true picture of the bridge dynamic behavior without any artificial force excitation when vibration data is recorded. A three-span reinforced concrete bridge located in Sri Medan, Batu Pahat, Johor was measured by using microtremor equipment consist of three units of 1 Hz eigenfrequency passive sensors used in this test was performed in normal operating condition without excitation required from any active sources or short period noise perturbations. Ten measurements were conducted on the bridge deck and ten measurements on the ground surface in order to identify the natural frequencies of the bridge. Several peak frequencies were identified from three components of Fourier Amplitude Spectra (FAS in transverse (North-South, longitudinal (East-West and vertical (Up-Down direction as well as squared average Horizontal to Vertical Spectral Ratio (HVSR of ground response, computed by using Geopsy software. From the result, it was expected the bridge have five vibration modes frequencies in the range of 1.0 Hz and 7.0 Hz with the first two modes in the transverse and longitudinal direction having a frequency 1.0 Hz, the third mode is 2.2 Hz in transverse direction, fourth and fifth mode is 5.8 Hz and 7.0 Hz. For ground natural frequencies are in range 1.0 Hz to 1.3 Hz for North-South direction and 1.0 Hz to 1.6 Hz for East-West direction. Finally the results are compared with several empirical formulas for simple

  13. V. Tormis: "Bridge of Song / Brian Hunt

    Index Scriptorium Estoniae

    Hunt, Brian

    1997-01-01

    Uuest heliplaadist "V. Tormis: "Bridge of Song" - Bridge of Song; Singing aboard ship; Brides Farewell; Kihnu Island Wedding Songs; 17 Estonian Wedding Songs; Three Estonian Game Songs; Four Estonian Lullabies. Estonian Radio Choir / Toomas Kapten. Finlandia 4509 96937-2; 56:52 DDD; "People of Kalevala" - God protect us from war; Vespian Winter; Eagle Flew From the North East; Plague Memory; Vainamoinen's Words of Wisdom; The Seventeenth Rune of Kalevala. National Male Choir of Estonia. Finlandia 0630 12245-2; 56:52 DDD

  14. Composite timber-concrete road bridge structure

    Directory of Open Access Journals (Sweden)

    Stojić Dragoslav

    2007-01-01

    Full Text Available This work presents preliminary design of the road bridge made of laminated timber. The supporting system of the main bearing elements is made of the laminated timber in the system of arch with three joints; the bridge slab is designed as continuous slab, made of nine equal fields; each pair is made as composite timber-concrete beam, where the road slab is made of concrete and the needle pieces are made of timber. Fundament is based on HW piles. All the elements are designed to Eurocode.

  15. Planar Hall effect bridge magnetic field sensors

    Science.gov (United States)

    Henriksen, A. D.; Dalslet, B. T.; Skieller, D. H.; Lee, K. H.; Okkels, F.; Hansen, M. F.

    2010-07-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar Hall effect bridge sensors.

  16. Experimental investigation of different fill materials in arch bridges with particular focus on Pearl-Chain Bridges

    DEFF Research Database (Denmark)

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Hertz, Kristian Dahl

    2016-01-01

    Pearl-Chain Bridge technology is a recently developed prefabricated arch solution for road and railway bridges allowing faster, more environmentally friendly, and cheaper bridge construction. This study compared the strength and durability properties of three different types of fill material...... to find the most optimal fill for Pearl-Chain Bridges. Sub-base gravel, cement-stabilized gravel, and pervious concrete were tested with respect to compressive strength, stiffness, splitting tensile strength, permeability, freeze–thaw durability, and shrinkage. This paper summarizes the advantages...... and disadvantages of implementing the different types of fill material in arch bridges, particularly in Pearl-Chain Bridges....

  17. Bridge Influence Line Estimation for Bridge Weigh-in-Motion System

    OpenAIRE

    Ieng, Sio Song

    2015-01-01

    This paper presents an algorithm that estimates the influence line (IL) of a bridge using data collected when trucks pass over the sensors installed in the bridge. The algorithm is tested with data collected from the Millau Viaduct in France using a bridge weigh-in-motion (B-WIM) device. The algorithm uses the maximum likelihood estimation (MLE) and is compared with an old algorithm. The algorithm is more robust because it takes into account many signals for the estimation of the IL.

  18. Safety evaluation system for anchored vessels in Tianjin anchorage under strong wind%天津港锚地大风条件下锚泊船安全评估系统

    Institute of Scientific and Technical Information of China (English)

    吴金龙; 吴彬贵; 刘大刚; 张斌; 罗红红

    2013-01-01

    To guarantee the safety of anchored vessels under strong wind, the safe lengths of let-going chain and the safe distance between vessels are calculated, and the warning grades of anchored vessels under strong wind in Tianjin anchorage is made according to the actual condition of Tianjin anchorage. A useful safety evaluation model for anchored vessels under strong wind in Tianjin anchorage is built. On that basis, the software of safety evaluation system for anchored vessels under strong wind in Tianjin anchorage is developed, which can provide the warning grades under the coming strong wind for each anchorage area in Tianjin anchorage dynamically and visually in advance of hours according to the wind speed forecast from meteorological department. It will be helpful to confirm the safety condition of anchored vessels for marine administration before strong wind coming, and reduce the accidents of dragging and collision, which can guarantee the safety production and enhance economic efficiency for shipping companies.%为保障大风期间船舶的锚泊安全,根据天津港锚地的具体情况,计算大风条件下天津港各锚地的安全出链长度和船舶之间的安全距离,制定天津港锚地大风条件下的锚泊船预警标准,建立可用于上述条件下的锚泊船实用安全评估模型.在此基础上,研制天津港锚地大风条件下的锚泊船安全评估系统软件.该软件可根据气象部门提供的大风风速预报,提前若干小时动态直观地给出天津港各锚地在未来大风条件下的预警等级,使得海事管理部门在大风来临前能够对锚泊船的锚泊状态进行安全确认,以减少大风来临时走锚和碰撞事故的发生,达到保障船运企业安全生产、提高经济效率的目的.

  19. Violin bridge mobility analysis under in-plane excitation.

    Science.gov (United States)

    Zhang, Cheng-Zhong; Zhang, Guang-Ming; Ye, Bang-Yan; Liang, Li-Dong

    2013-11-08

    The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2-3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.

  20. Foot force models of crowd dynamics on a wobbly bridge

    CERN Document Server

    Belykh, Igor; Belykh, Vladamir

    2016-01-01

    Modern pedestrian and suspension bridges are designed using industry-standard packages, yet disastrous resonant vibrations are observed, necessitating multi-million dollar repairs. Recent examples include pedestrian induced vibrations during the openings of the Solf\\'erino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase-locking due to footstep phase adjustment, is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. In this paper, we develop foot force models of pedestrians' response to bridge motion and detailed, yet analytically tractable models of crowd phase-locking. We use bio-mechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to ...

  1. CDC WONDER: Population - Bridged-Race July 1st Estimates

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Population - Bridged-Race July 1st Estimates online databases report bridged-race population estimates of the July 1st resident population of the United States,...

  2. Hydraulic bridges in unsaturated coarse granular media: Influence of bridge size and conductivity on flow through clasts

    Science.gov (United States)

    Jayakody, Jeevan A.; Nicholl, Michael J.

    2016-10-01

    Unsaturated flow in coarse granular media must pass through hydraulic bridges (e.g., pendular water, porous connections) that form a physical connection between adjoining clasts. Previous studies suggest that volumetric flow through a porous clast (Q) will be linearly dependent on the cross-sectional area of the hydraulic bridges, and understate the importance of bridge conductivity. Numerical simulations were performed to explore steady-state flow through a spherical clast with identical bridges located at the top and bottom. The cross-sectional area of the bridges relative to that of the clast (Ar) was varied across six orders of magnitude. The ratio of hydraulic conductivity between bridges and clasts (Kb/Kc) was varied across 12 orders of magnitude to consider resistive, neutral, and conductive bridges. Results show that hydraulic bridges place a primary control on both Q and flux distribution within the clast. For neutral and conductive bridges (Kb/Kc ≥1), Ar is the dominant factor in determining Q, while Kb/Kc is the primary control for resistive bridges (Kb/Kc < 1). For all bridges, Q shows a non-linear dependency on both Ar and Kb/Kc. The intra-clast flow distribution shifts outwards as Ar increases. Conductive bridges promote this process and resistive bridges impede it.

  3. Steel plate reinforcement of orthotropic bridge decks

    NARCIS (Netherlands)

    Teixeira de Freitas, S.

    2012-01-01

    The PhD research is focused on the reinforcement of fatigue cracked orthotropic steel bridge decks (OBD) by adding a second steel plate to the existing deck. The main idea is to stiffen the existing deck plate, which will reduce the stresses at the fatigue sensitive details and extend the fatigue li

  4. LPN/ADN Bridge Course. Instructor's Guide.

    Science.gov (United States)

    Barrett, Jan; And Others

    This curriculum guide has been constructed in order to bridge the skills gap between licensed practical nursing (LPN) programs and associate degree nursing (ADN) programs in Missouri. The curriculum was developed through a cooperative effort by persons from both sectors. The curriculum contains four major units, each consisting of several lessons,…

  5. Images Bridging Home and Academic Cultures.

    Science.gov (United States)

    Andres, Sophia

    Often students are unable to draw upon their personal worlds and individual experiences to enrich their writing, suggesting a disparity between home and academic cultures. In light of this apparent disparity, teachers must try to bridge the gap, a task that is possible when the teacher focuses on the germinal, emotional, and unifying qualities of…

  6. The mechanics of ship impacts against bridges

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    a glancing blow between the ship and the bridge structure. This model is based on rigid body mechanics and well suited for inclusion in a probabilistic analysis procedure. Finally, some empirical expressions are presented which relate the energy absorbed by crushing of ship structures to the maximum impact...

  7. Bridging the digital divide with mobile services

    CERN Document Server

    Yelton, Andromeda

    2013-01-01

    In this issue of Library Technology Reports, Andromeda Yelton shows how libraries can build on the breadth of this population to help bridge the digital divide and provide even greater access to information. Yelton breaks down the demographics of mobile internet users, provides examples of how different libraries are reaching out to these populations, and suggests what the future may hold for this trend.

  8. New Program Builds Bridges for Hearing Impaired.

    Science.gov (United States)

    Johnson, Jeannie

    1998-01-01

    Describes a new approach to teaching English-as-a-Second-Language to New Mexico elementary school students who have hearing impairments and whose dominant language is American Sign Language (ASL). These students must first acquire ASL as a bridge to learning English. Then, using the bilingual approach, they are able to focus on English literacy.…

  9. Ergonomic aspects of automation in navigation bridges

    NARCIS (Netherlands)

    Lazet, A.; Walraven, P.L.

    1971-01-01

    New ergonomic questions arise from the tendency toward increasing automation in maritime operations. Direct control of engines and rudder from the bridge promises improved ship control, provided that the operator can really exploit the technical improvements. To make such direct control most efficie

  10. Fiber reinforced polymer composites for bridge structures

    Directory of Open Access Journals (Sweden)

    Alexandra CANTORIU

    2013-12-01

    Full Text Available Rapid advances in construction materials technology have led to the emergence of new materials with special properties, aiming at safety, economy and functionality of bridges structures. A class of structural materials which was originally developed many years ago, but recently caught the attention of engineers involved in the construction of bridges is fiber reinforced polymer composites. This paper provides an overview of fiber reinforced polymer composites used in bridge structures including types, properties, applications and future trends. The results of this study have revealed that this class of materials presents outstanding properties such as high specific strength, high fatigue and environmental resistance, lightweight, stiffness, magnetic transparency, highly cost-effective, and quick assembly, but in the same time high initial costs, lack of data on long-term field performance, low fire resistance. Fiber reinforced polymer composites were widely used in construction of different bridge structures such as: deck and tower, I-beams, tendons, cable stands and proved to be materials for future in this field.

  11. Aeroelastic Stability of Suspension Bridges using CFD

    DEFF Research Database (Denmark)

    Stærdahl, Jesper Winther; Sørensen, Niels; Nielsen, Søren R.K.

    2007-01-01

    In recent years large span suspension bridges with very thin and slender profiles have been built without proportional increasing torsional and bending stiffness. As a consequence large deformations at the mid-span can occur with risk of aeroelastic instability and structural failure. Analysis...

  12. Bridge monitoring using heterogeneous wireless sensor network

    Science.gov (United States)

    Haran, Shivan; Kher, Shubhalaxmi; Mehndiratta, Vandana

    2010-03-01

    Wireless sensor networks (WSN) are proving to be a good fit where real time monitoring of multiple physical parameters is required. In many applications such as structural health monitoring, patient data monitoring, traffic accident monitoring and analysis, sensor networks may involve interface with conventional P2P systems and it is challenging to handle heterogeneous network systems. Heterogeneous deployments will become increasingly prevalent as it allows for systems to seamlessly integrate and interoperate especially when it comes to applications involving monitoring of large infrastructures. Such networks may have wireless sensor network overlaid on a conventional computer network to pick up data from one distant location and carry out the analysis after relaying it over to another distant location. This paper discusses monitoring of bridges using WSN. As a test bed, a heterogeneous network of WSN and conventional P2P together with a combination of sensing devices (including vibration and strain) is to be used on a bridge model. Issues related to condition assessment of the bridge for situations including faults, overloads, etc., as well as analysis of network and system performance will be discussed. When conducted under controlled conditions, this is an important step towards fine tuning the monitoring system for recommendation of permanent mounting of sensors and collecting data that can help in the development of new methods for inspection and evaluation of bridges. The proposed model, design, and issues therein will be discussed, along with its implementation and results.

  13. Circuit bridging of components by smoke

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T.J.; Nowlen, S.P.; Anderson, D.J. [Sandia National Labs., Albuquerque, NM (United States)

    1996-10-01

    Smoke can adversely affect digital electronics; in the short term, it can lead to circuit bridging and in the long term to corrosion of metal parts. This report is a summary of the work to date and component-level tests by Sandia National Laboratories for the Nuclear Regulatory Commission to determine the impact of smoke on digital instrumentation and control equipment. The component tests focused on short-term effects such as circuit bridging in typical components and the factors that can influence how much the smoke will affect them. These factors include the component technology and packaging, physical board protection, and environmental conditions such as the amount of smoke, temperature of burn, and humidity level. The likelihood of circuit bridging was tested by measuring leakage currents and converting those currents to resistance in ohms. Hermetically sealed ceramic packages were more resistant to smoke than plastic packages. Coating the boards with an acrylic spray provided some protection against circuit bridging. The smoke generation factors that affect the resistance the most are humidity, fuel level, and burn temperature. The use of CO{sub 2} as a fire suppressant, the presence of galvanic metal, and the presence of PVC did not significantly affect the outcome of these results.

  14. Thermal Bridge Effects in Window Grooves

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    In this report thermal bridge effects in window grooves are analyzed. The analysis is performed using different thicknesses of the window groove insulation, to evaluate what the optimal solution is.All analysis in the report is performed using both 2- and 3-dimensional numerical analysis....

  15. RISK LEVEL ANALYSIS ON THE PREVENTIVE EROSION CAPACITY OF BRIDGES

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Deficiency of the Preventive Erosion Capacity (PEC) of a bridge pier is the main factor leading to bridge failures. In this paper, the PEC of bridge piers was analyzed using the stochastic analysis method. The definitions of the reliability and risk level of a bridge pier subjected to water erosion were proposed and a computational model for erosion depth and risk level in was suggested.

  16. Nondestructive evaluation inspection of the Arlington Memorial Bridge using a robotic assisted bridge inspection tool (RABIT)

    Science.gov (United States)

    Gucunski, Nenad; Boone, Shane D.; Zobel, Rob; Ghasemi, Hamid; Parvardeh, Hooman; Kee, Seong-Hoon

    2014-04-01

    The information presented in this report provides a detailed assessment of the condition of the Arlington Memorial Bridge (AMB) deck. The field-data collection was obtained by both the RABIT™ Bridge Inspection Tool and a number of semi-automated non-destructive evaluation (NDE) tools. The deployment of the semi-automated NDE tools was performed to inspect the AMB deck condition and also to validate data obtained by the RABIT™ Bridge Inspection Tool. Data mining and analysis were accomplished through enhanced data interpretation and visualization capabilities using advanced data integration, fusion, and 2D rendering. One of the major challenges that the research team had to overcome in assessing the condition of the AMB deck was the presence of an asphalt overlay on the entire bridge deck.

  17. Railroad Bridges in Louisiana, Geographic NAD83, FEMA (1997) [railroad_bridges_FEMA_1997

    Data.gov (United States)

    Louisiana Geographic Information Center — This is is a point dataset for the locations and attributes of 32 Louisiana railroad bridges. The attributes include city (nearest?), county (sic), routefrom (city),...

  18. Performance Assessment of Bridges Using GPS: The Juarez Bridge in Culiacan, Mexico

    Science.gov (United States)

    Vazquez, G. E.; Gaxiola-Camacho, J. R.; Trejo, M.; Echagaray, J.; Guzman, G. M.

    2015-12-01

    Performance assessment of bridges has become very important during recent years. Bridges around the world are aging, leading to the incorporation of efficient, reliable, and economic evaluation procedures. These techniques must assess properly the performance of bridges under several loading conditions in a real manner, representing the physics of the problem. Among several approaches, Global Positioning System (GPS) can be intelligently used for the performance evaluation of bridges. We focused on GPS, since it naturally produces position estimates as compared to seismic instruments that record either velocity or acceleration, and thus require an integration. There are several reasons that make the Juarez Bridge a case of study for evaluation: it is approximately 45 years old, it is a reinforced concrete structure, it connects two significant zones of the city, and its spans is closely to 200 meters long. In addition, thousands of vehicles and pedestrians use the Juarez Bridge every day, which make feasible the GPS performance assessment. Hence, in order to produce optimal position estimates, GPS data were collected during two consecutive hours at three different periods of the day for a whole week (Monday through Sunday), to represent three critical limit states of the bridge (mid-span and end-spans). GPS data were processed using the GAMIT/GLOBK software, considering 1-second sampling rate, 15-degree cutoff angle, ionosphere-free double-differenced (DD) carrier phase method, and precise final orbits disseminated by IGS (International GNSS Service). The displacements obtained from the above discussed procedure are compared with allowable values documented in bridge construction manuals. Reliability theory was used to evaluate the probability of failure of the bridge for the three periods of the day. In addition, a conclusion was made about the most risky day of the week for the use of the Juarez Bridge. It is expected that the results from the proposed research

  19. Movimentação de molares inferiores ancorados em mini-parafusos Mandibular molar uprighting, using mini-screw as anchorage

    Directory of Open Access Journals (Sweden)

    Rosana Canteras Di Matteo

    2005-08-01

    Full Text Available Freqüentemente a movimentação ortodôntica exige recursos adicionais de ancoragem. Os mini-parafusos têm-se apresentado como uma possível solução. O propósito deste trabalho foi estabelecer um método para a verticalização de molares inferiores inclinados para mesial, utilizando ancoragem em mini-parafusos colocados na região de linha oblíqüa externa da mandíbula. Foram selecionados três pacientes entre 40 a 48 anos (dois do gênero feminino, um do gênero masculino, com molares inferiores inclinados para mesial e distalmente posicionados às áreas edêntulas. Os pacientes foram tratados ortodonticamente durante um período de 6 a 12 meses, com técnica ortodôntica MD3. Mini-parafusos de titânio foram colocados bilateralmente com anestesia local. Uma incisão sobre a linha oblíqüa externa da mandíbula, medindo aproximadamente 1 cm foi realizada em cada lado, distalmente aos molares inclinados. Após descolamento muco-periosteal, mini-parafusos foram implantados e foram realizadas suturas deixando suas cabeças exteriorizadas. Uma semana após a remoção das suturas, cargas ortodônticas (entre 150 a 200 gramas/força foram aplicadas através de forças elásticas. Verificamos que alguma inflamação foi observada ao redor dos mini-parafusos, mas foi controlada com procedimentos de higienização. O procedimento cirúrgico é simples, podendo ser realizado pelo ortodontista; as formas dimensionais dos mini-parafusos são adequadas e estes são de fácil remoção após uso. Concluímos que o uso de mini-parafusos representa uma alternativa efetiva de ancoragem ortodôntica na verticalização de molares inferiores.Tooth movement frequently requires additional anchorage resources. Mini-screws have been used as a possible solution to this matter. The purpose of this study was to establish a method of mandibular molar uprighting, using mini-screw as anchorage, positioned on the mandibular external oblique line, behind and

  20. Ambient Response Analysis of the Great Belt Bridge

    DEFF Research Database (Denmark)

    Brincker, Rune; Frandsen, J. B.; Andersen, P.

    2000-01-01

    In this paper an ambient response analysis of the Great Belt Bridge is presented. The Great Belt Bridge is one of the largest suspension bridges in the world, and the analysis was carried out in order to investigate the possibilities of estimating reliable damping values from the ambient response...

  1. Resin-Bonded Bridges in vitro and in vivo

    NARCIS (Netherlands)

    Veen, Johannes Hilbrandt van der

    1988-01-01

    In this thesis in vitro and in vivo studies on the clinical application of resin-bonded bridges are described and discussed. The development of different types of resin-bonded bridges is described in chapter 1. The bridges are often made by boding a cast metal retainer fitted with and artificial too

  2. Renovation techniques for fatigue cracked orthotropic steel bridge decks

    NARCIS (Netherlands)

    de Jong, F.B.P.

    2007-01-01

    This dissertation presents the research into renovation techniques for orthotropic steel bridge decks. These techniques are needed to solve fatigue problems in the decks of these bridges, as several fatigue cracks have been detected in the deck structure of these bridges the last decade. A well-know

  3. A calculation model for the noise from steel railway bridges

    NARCIS (Netherlands)

    Janssens, M.H.A.; Thompson, D.J.

    1996-01-01

    The sound level of a train crossing a steel railway bridge is usually about 10 dB higher than on plain track. In the Netherlands there are many such bridges which, for practical reasons, cannot be replaced by more intrinsically quiet concrete bridges. A computational model is described for the estim

  4. Dynamic Vehicle Impact for Safety Assessment of Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    In this paper the dynamic amplification of vehicle load at minor highway bridges is considered for safety assessment of the load carrying capacity of bridges. The considered case is the most critical for bridges, i.e. the simultaneous passage of two heavy trucks. A short description...

  5. 33 CFR 115.50 - Application for bridge permits.

    Science.gov (United States)

    2010-07-01

    ... authority not necessary. Coast Guard approval of the location and plans for construction or modification of a bridge or causeway is not required for any bridge or causeway over waters which are not subject to... (historic use). This provision does not apply to bridges which connect the United States with any...

  6. Future Trends in Reliability-Based Bridge Management

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Future bridge management systems will be based on simple stochastic models predicting the residual strength of structural elements. The current deterministic management systems are not effective in optimizing e.g. the life cycle cost of a bridge or a system of bridges. A number of important factors...

  7. 21 CFR 872.3770 - Temporary crown and bridge resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Temporary crown and bridge resin. 872.3770 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a material, such...

  8. Seismic Performance of Multi-Span RC Railway Bridges

    DEFF Research Database (Denmark)

    Georgakis, Christos; Barrau, Xavier

    2008-01-01

    Presently, there is no clear method for determining the optimal railway bridge design for a particular ground type and expected seismic intensity. Four main types of RC bridge dominate the current multi-span railway bridge design trends – the Simply Supported Beam, Continuous Box-Girder (CBG), CBG...

  9. Reduction of Impact Noise of Trams on a Major Bridge

    NARCIS (Netherlands)

    Dittrich, M.G.; Bosshaart, C.; Wessels, P.W.

    2015-01-01

    As part of a recent renovation of the Erasmus bridge in Rotterdam, improvements were made to reduce impact noise caused by trams passing a series of rai! joints. The bridge inciudes several different sections inciuding a bascule bridge and is in an inner city tocation with new adjacent apartment bui

  10. Improving the Dynamics of Suspension Bridges using Active Control Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Improving the dynamics of suspension bridge using active control is discussed in this paper. The main dynamic problem with long suspension bridges is the aeroelastic phenomenon called flutter. Flutter oscillations of a bridge girder is a stability problem and the oscillations are perpendicular...

  11. Reliability-Based Optimization for Maintenance Management in Bridge Networks

    OpenAIRE

    Hu, Xiaofei

    2014-01-01

    This dissertation addresses the problem of optimizing maintenance, repair and reconstruction decisions for bridge networks. Incorporating network topologies into bridge management problems is computationally difficult. Because of the interdependencies among networked bridges, they have to be analyzed together. Simulation-based numerical optimization techniques adopted in past research are limited to networks of moderate sizes. In this dissertation, novel approaches are developed to dete...

  12. Road Bridges and Culverts, Bridges layers located in GIS and Transportation database., Published in unknown, City of Roswell, GA.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset as of unknown. It is described as 'Bridges layers located in GIS and Transportation database.'. Data by this publisher are...

  13. 基于Mindlin解的压力型锚杆锚固段的受力分析%Mechanical analysis of anchorage segment of pressure-type cable based on the Mindlin solution

    Institute of Scientific and Technical Information of China (English)

    贺建清; 胡成兵; 张建超

    2012-01-01

    假设锚杆为与周围介质相同的材料,视锚杆作用的岩土体为弹性半空间位移体;基于Mindlin位移解,求出集中力作用下周围岩土体沿锚固体的轴向位移;根据压力型锚杆锚固段的受力状态,计算锚固体在轴向荷载作用下压缩变形,利用锚固体与周围岩土体变形协调假定,推导出锚固段轴向应力和剪应力分布的理论解.经过与已有现场试验实测数据对比分析,验证了理论解的可行性,并在此基础上讨论了相关岩土参数对锚固段轴向应力和剪应力的影响.锚杆现场试验和理论分析结果表明:压力型锚杆的锚固段所受轴向应力和剪应力与锚固力成正比;压力型锚杆的锚固段所受剪应力的分布形式受周围岩土体弹模、泊松比以及锚固体与周围岩土体界面的内摩擦角等因素的影响.其中周围岩土体的弹模影响最大.%Assuming that cable has the same material properties with the surrounding rock soil and there is a displacement in an elastic half-space occurred for the rock and soil mass reinforced with cable, axial displacement of surrounding rock soil mass along cable under anchorage force was calculated based on Mindlin displacement solution. Based on the stress state of anchorage segment of pressure-type cable, the compression deformation of anchorage body under axial load was also obtained. Theoretical solutions for the distribution of axial stress and shear stress on anchorage segment of pressure-type cable were derived on the assumption of a compatible deformation between anchorage body and surrounding rock soil mass. After comparing with the existed data of in-situ test, theoretical solutions proved to be feasible. On this basis, the influence of related mechanical parameters of rock and soil on shear stress and axial stress were discussed. Experimental and theoretical analysis results indicated that the axial normal stress and shear stress on anchorage segment of

  14. Mesialização de molares com ancoragem em mini-implantes Mesial movement of molars with mini-implants anchorage

    Directory of Open Access Journals (Sweden)

    Marcos Janson

    2008-10-01

    Full Text Available INTRODUÇÃO: é muito comum, na rotina do consultório odontológico, especialmente em Ortodontia, o paciente, após avaliar o plano de tratamento proposto, questionar sobre a possibilidade de fechamento de espaços presentes, ocasionados pela perda de dentes permanentes. O ortodontista, frente a essa questão, tem que avaliar diversos fatores, tais como a má oclusão presente, a integridade do osso e das raízes, o tempo de tratamento e a geometria do posicionamento dentário, que é o que permite avaliar se, com o fechamento dos espaços e, conseqüentemente, a perda de ancoragem dos segmentos anteriores, a finalização estará de acordo com os ideais que regem a especialidade. Com o advento dos mini-implantes, as possibilidades desta abordagem terapêutica aumentaram, pois o efeito adverso da perda de ancoragem pode ser eliminado e, com isso, o paciente pode ser beneficiado. No entanto, os outros fatores envolvidos, assim como a mecânica do movimento, requerem especial atenção. OBJETIVOS: no presente artigo serão abordados os fatores envolvidos neste tipo de tratamento, o raciocínio na tomada de decisões e os detalhes importantes que devem ser observados durante a condução da mecânica, ilustrados com casos clínicos.INTRODUCTION: It's routine, especially at the orthodontic office, the patient, after the assessment of the proposed treatment plan, answer about the possibility of closing their edentulous spaces caused by missed permanent teeth. In these situations, several factors must be evaluated, like the present malocclusion, the bone and roots integrity, the treatment time and the geometry of teeth positioning, that is what permits to assess if the loss of anchorage from the anterior segments, during the space closure, would permit the occlusion to end within the orthodontic ideals. With the mini-implants, the possibilities of this therapeutic approach have been improved, since the adverse effects are eliminated with the

  15. 微种植体支抗在安氏Ⅱ类1分类错牙合中的应用%The Application of Micro-implants Anchorage in Angle Class Ⅱ Division 1 Malocclusion

    Institute of Scientific and Technical Information of China (English)

    王铭蔚

    2012-01-01

    Angle class Ⅱ division 1 malocclusion prevalence is high. The premise of such disease to be successfully treated is the perfect anchorage control. Mini-implants anchorage provides stable anchorage effects for the orthodontic treatment, which is recognized and accepted by the majority of physicians. In practical application process, how to optimize the use of micro-implants to treatment of Angle class Ⅱ division 1 malocclusion is one of the difficulties in orthodontic.%安氏Ⅱ类1分类错牙合畸形患病率较高,正确的支抗设计和良好的支抗控制是这类错牙合获得成功矫治的前提.近年来,微种植体支抗由于为正畸治疗中提供稳定支抗效果而逐渐被广大医师认识和接受.在实际应用过程中,如何优化使用微种植体治疗安氏Ⅱ类1分类错牙合是当今正畸治疗的难点之一.

  16. 提高车辆安全带锚固点强度的方法研究%Study on improving the strength of the seat-belts anchorages

    Institute of Scientific and Technical Information of China (English)

    韩淑洁

    2012-01-01

    按照国家标准要求,对某型汽车座椅安全带进行强度试验,发现后排座椅安全带锚点处的后地板破裂.针对该问题,在ANSYS软件中建立了座椅安全带的有限元模型,通过有限元分析结果与试验结果的对比,证明有限元模型的可靠性.利用非线性有限元法对安全带锚固点的强度进行了研究,提出了一些可以提高安全带锚固点强度的方法.%According to the national standards requiements , the strength test was done to the seat-belts of a certain type of cars. The results show that the strength of rear seat-belt anchorages cound not meet the national standards. According to the national standards, a finite element model of the seat-belts was built using ANSYS software. The results of the finite element simulation analysis were compared with the experimental results, which proved the reliability of finite element model. The strength of belts anchorages was studied using nonlinear finite element method, and some methods were put forward in order to improve the strength of seat-belt anchorages.

  17. Dynamic analysis of rail transit elevated bridge with ladder track

    Institute of Scientific and Technical Information of China (English)

    He XIA; Yushu DENG; Yongwei ZOU; Guido DE ROECK; Geert DEGRANDE

    2009-01-01

    In this paper, a dynamic analysis model of an elevated bridge with ladder tracks under moving train load is established. The whole process of a train running through an elevated bridge at different speeds is simulated.The dynamic responses of the elevated bridge with ladder track and the running safety and comfort index of train vehicles are evaluated. Compared with the dynamic responses of an elevated bridge with ordinary non-ballasted slab track, the ladder track's effect on reducing the vibration of an elevated bridge is analyzed. The analysis results show that the ladder track has good vibration reduction characteristics as compared to ordinary non-ballasted track.

  18. Seismic Passive Control of Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Hosam-Eddin M. Ali

    1995-01-01

    Full Text Available A three-dimensional modeling procedure is proposed for cable-stayed bridges with rubber, steel, and lead energy dissipation devices. The passive control technique is investigated by considering the response of bridge models with and without energy dissipation devices. The impact of various design parameters on the seismic response of current and future bridge designs is studied. Appropriate locations and properties of the passive devices can achieve better performance for cable-stayed bridges by balancing the significant reduction in earthquake-induced forces against tolerable displacements. Proper design of passive systems can help provide solutions for retro-fitting some existing bridges.

  19. An effective Handling of Thermal Bridges in the EPBD Context

    DEFF Research Database (Denmark)

    Erhorn, Hans; Erhorn-Kluttig, Heike; Thomsen, Kirsten Engelund;

    The ASIEPI project has collected and analysed international and national information from up to 17 EU Member States plus Norway on the topic of thermal bridges in buildings. Seven different aspects have been addressed, ranging from EU Member States’ approaches in regulations to quantification...... of thermal bridge effects to the energy balance, used software tools and thermal bridge atlases, available good practice guidance and promotion of good building practice to the execution quality and advanced thermal bridge driven technical developments. This report presents the gathered knowledge, draws...... junctions and other building parts with possible thermal bridges....

  20. Suspension Bridge Flutter for Girder with Separate Control Flaps

    DEFF Research Database (Denmark)

    Huynh, T.; Thoft-Christensen, Palle

    Active vibration control of long span suspension bridge flutter using separated control flaps (SFSC) has shown to increase effectively the critical wind speed of bridges. In this paper, an SFSC calculation based on modal equations of the vertical and torsional motions of the bridge girder including...... the flaps is presented. The length of the flaps attached to the girder, the flap configuration and the flap rotational angles are parameters used to increase the critical wind speed of the bridge. To illustrate the theory a numerical example is shown for a suspension bridge of 1000m+2500m+1000m span based...

  1. Dynamics and statics of nonaxisymmetric and symmetric liquid bridges

    Science.gov (United States)

    Alexander, J. Iwan D.; Resnick, Andrew H.; Kaukler, William F.; Zhang, Yiqiang

    1994-01-01

    This program of theoretical and experimental ground-based research focuses on the understanding of the dynamics and stability limits of nonaxisymmetric and symmetric liquid bridges. There are three basic objectives: First, to determine the stability limits of nonaxisymmetric liquid bridges held between non-coaxial parallel disks, Second, to examine the dynamics of nonaxisymmetric bridges and nonaxisymmetric oscillations of initially axisymmetric bridges. The third objective is to experimentally investigate the vibration sensitivity of liquid bridges under terrestrial and low gravity conditions. Some of these experiments will require a low gravity environment and the ground-based research will culminate in a definitive flight experiment.

  2. The effect of canine disimpaction performed with temporary anchorage devices (TADs before comprehensive orthodontic treatment to avoid root resorption of adjacent teeth

    Directory of Open Access Journals (Sweden)

    Farzin Heravi

    2016-04-01

    Full Text Available ABSTRACT Objective: The aim of this study was to evaluate the movement of impacted canines away from the roots of neighboring teeth before full-mouth bracket placement, performed by means of TADs to decrease undesired side effects on adjacent teeth. Methods: The study sample consisted of 34 palatally impacted canines, being 19 in the experimental group and 15 in the control group. In the experimental group, before placement of brackets, the impacted canine was erupted by means of miniscrews. In the control group, after initiation of comprehensive orthodontics, canine disimpaction was performed by means of a cantilever spring soldered to a palatal bar. At the end of treatment, volume of lateral incisors and canine root resorption were measured and compared by means of a CBCT-derived tridimensional model. Visual Analogue Scale (VAS score, bleeding on probing (BOP and gingival index (GI were recorded. Clinical success rate was also calculated. Results: The volume of root resorption of lateral teeth in the control group was significantly greater than in the experimental group (p < 0.001. At the end of treatment, VAS score, GI and BOP were not significantly different between the two groups. Conclusion: Based on our results, it seems that disimpaction of canines and moving them to the arch can be done successfully carried out with minimal side effects by means of skeletal anchorage.

  3. Induction of anchorage-independent growth in primary human cells exposed to protons or HZE ions separately or in dual exposures.

    Science.gov (United States)

    Sutherland, B M; Cuomo, N C; Bennett, P V

    2005-10-01

    Travelers on space missions will be exposed to a complex radiation environment that includes protons and heavy charged particles. Since protons are present at much higher levels than are heavy ions, the most likely scenario for cellular radiation exposure will be proton exposure followed by a hit by a heavy ion. Although the effects of individual ion species on human cells are being investigated extensively, little is known about the effects of exposure to both radiation types. One useful measure of mammalian cell damage is induction of the ability to grow in a semi-solid agar medium highly inhibitory to the growth of normal human cells, termed neoplastic transformation. Using primary human cells, we evaluated induction of soft-agar growth and survival of cells exposed to protons only or to heavy charged particles (600 MeV/nucleon silicon) only as well as of cells exposed to protons followed after a 4-day interval by silicon ions. Both ions alone efficiently transformed the human cells to anchorage-independent growth. Initial experiments indicate that the dose responses for neoplastic transformation of cells exposed to protons and then after 4 days to silicon ions appear similar to that of cells exposed to silicon ions alone.

  4. Apical root resorption in maxillary incisors when employing micro-implant and J-hook headgear anchorage: a 4-month radiographic study.

    Science.gov (United States)

    Wang, Qingzhu; Chen, Wenjing; Smales, Roger J; Peng, Hui; Hu, Xiaokun; Yin, Lu

    2012-10-01

    This study evaluated, over a 4-month study period, the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage. The prospective randomised clinical trial was conducted in Orthodontic Clinic, College of Stomatology, China from 2008-2009. Subjects are patients requiring fixed appliances on waiting list (n=20). In female Han Chinese patients aged from 16-26 years, standardized periapical radiographs from 10 randomly assigned patients with maxillary protrusions comprising the micro-implant group, and from 10 similar patients comprising the J-hook headgear group, were assessed for maxillary central incisor apical root resorption. Measurements before and after orthodontic therapy were also obtained from lateral cephalometric radiographs to calculate incisor horizontal retraction and vertical intrusion distances. Estimated retraction force vectors were calculated in horizontal and vertical directions for both treatment groups. Data analysis employed t-tests and the Pearson correlation test, with α=0.05 for statistical significance. The results showed that when compared with the J-hook group, significantly more apical root resorption shortening of the maxillary central incisors was observed in the micro-implant group (1.27 mm difference, 95% CI=0.70-1.84, Presorption shortening and maxillary central incisor retraction than when intermittent J-hook retraction was employed. The employment of continuous duration orthodontic forces presents a risk for increased apical root resorption that requires careful radiographic monitoring.

  5. Approximation and contact of the maxillary central incisor roots with the incisive canal after maximum retraction with temporary anchorage devices: Report of 2 patients.

    Science.gov (United States)

    Chung, Chooryung J; Choi, Yoon Jeong; Kim, Kyung-Ho

    2015-09-01

    The incisive canal is located on the median plane of the maxilla, posterior to the roots of the central incisor. Although the incisive canal is not considered an anatomic structure that may limit tooth movement, it has recently gained attention regarding the possibilities of surgical invasion and associated complications because of its proximity to the maxillary central incisors. In the 2 illustrated cases, lip protrusion was improved by en-masse bodily retraction of the anterior teeth (>8 mm) using temporary anchorage devices. Three-dimensional cone-beam computed tomography showed that the maxillary incisor roots were approximated to the incisive canal after maximum retraction. One central incisor root was in direct contact with the incisive canal with severe root resorption, but tooth vitality and the overall occlusion were stable in the long term without any sensory dysfunction. The apparent root resorption may be mainly related to the large amounts of anterior retraction and root movement in the 2 patients. However, the anatomic location of the incisive canal and the possibilities of its invasion after tooth movement should be closely monitored when maximum retraction is planned, to prevent potential complications.

  6. The effect of canine disimpaction performed with temporary anchorage devices (TADs) before comprehensive orthodontic treatment to avoid root resorption of adjacent teeth

    Science.gov (United States)

    Heravi, Farzin; Shafaee, Hooman; Forouzanfar, Ali; Zarch, Seyed Hossein Hoseini; Merati, Mohsen

    2016-01-01

    ABSTRACT Objective: The aim of this study was to evaluate the movement of impacted canines away from the roots of neighboring teeth before full-mouth bracket placement, performed by means of TADs to decrease undesired side effects on adjacent teeth. Methods: The study sample consisted of 34 palatally impacted canines, being 19 in the experimental group and 15 in the control group. In the experimental group, before placement of brackets, the impacted canine was erupted by means of miniscrews. In the control group, after initiation of comprehensive orthodontics, canine disimpaction was performed by means of a cantilever spring soldered to a palatal bar. At the end of treatment, volume of lateral incisors and canine root resorption were measured and compared by means of a CBCT-derived tridimensional model. Visual Analogue Scale (VAS) score, bleeding on probing (BOP) and gingival index (GI) were recorded. Clinical success rate was also calculated. Results: The volume of root resorption of lateral teeth in the control group was significantly greater than in the experimental group (p < 0.001). At the end of treatment, VAS score, GI and BOP were not significantly different between the two groups. Conclusion: Based on our results, it seems that disimpaction of canines and moving them to the arch can be done successfully carried out with minimal side effects by means of skeletal anchorage. PMID:27275617

  7. Upregulation of DNA methyltransferase-mediated gene silencing, anchorage-independent growth, and migration of colon cancer cells by interleukin-6.

    Science.gov (United States)

    Foran, Eilis; Garrity-Park, Megan M; Mureau, Coralie; Newell, John; Smyrk, Thomas C; Limburg, Paul J; Egan, Laurence J

    2010-04-01

    Inflammatory bowel disease is characterized by chronic inflammation which predisposes to colorectal cancer. The mechanisms by which inflammation promotes tumorigenesis are not fully known. We aimed to investigate the links between colonic inflammation and tumorigenesis via epigenetic gene silencing. Colon cancer specimens were assessed for the expression of DNA methyltransferase-1 (DNMT-1) using immunohistochemistry. Colorectal carcinoma cell lines were assessed for DNMT1 expression, methylcytosine content, promoter methylation, gene expression, and tumorigenesis in response to interleukin (IL)-6. DNMT1 was expressed at higher levels in both the peritumoral stroma and tumor in inflammatory bowel disease-associated cancers compared with sporadic colon cancers. IL-6 treatment of colon cancer cells resulted in an increase in DNMT1 expression, independent of de novo gene expression. IL-6 increased the methylation of promoter regions of genes associated with tumor suppression, adhesion, and apoptosis resistance. Expression of a subset of these genes was downregulated by IL-6, an effect that was prevented by preincubation with 5-azadeoxycytidine, a DNMT1 inhibitor. Anchorage-independent growth and migration of colon cancer cells was also increased by IL-6 in a 5-azadeoxycytidine-sensitive manner. Our results indicate that DNMT-mediated gene silencing may play a role in inflammation-associated colon tumorigenesis.

  8. MicroRNA let-7b targets important cell cycle molecules in malignant melanoma cells and interferes with anchorage-independent growth

    Institute of Scientific and Technical Information of China (English)

    Julia Schultz; Peter Lorenz; Gerd Gross; Saleh Ibrahim; Manfred Kunz

    2008-01-01

    A microRNA expression screen was performed analyzing 157 different microRNAs in laser-microdissected tissues from benign melanocytic nevi (n=10) and primary malignant melanomas (n=10),using quantitative real-time PCR.Differential expression was found for 72 microRNAs.Members of the let-7 family of microRNAs were significantly downregulated in primary melanomas as compared with benign nevi,suggestive for a possible role of these molecules as tumor suppressors in malignant melanoma.Interestingly,similar findings had been described for lung and colon cancer.Overexpression of let-7b in melanoma cells in vitro downregulated the expression of cyclins D1,D3,and A,and cyclin-dependent kinase (Cdk) 4,all of which had been described to play a role in melanoma development.The effect oflet-7b on protein expression was due to targeting of 3'-untranslated regions (3'UTRs) of individual mRNAs,as exemplified by reporter gene analyses for cyclin DI.In line with its downmodulating effects on cell cycle regulators,let-7b inhibited cell cycle progression and anchorage-independent growth of melanoma cells.Taken together,these findings not only point to new regulatory mechanisms of early melanoma development,but also may open avenues for future targeted therapies of this tumor.

  9. A Review of Indirect Bridge Monitoring Using Passing Vehicles

    Directory of Open Access Journals (Sweden)

    Abdollah Malekjafarian

    2015-01-01

    Full Text Available Indirect bridge monitoring methods, using the responses measured from vehicles passing over bridges, are under development for about a decade. A major advantage of these methods is that they use sensors mounted on the vehicle, no sensors or data acquisition system needs to be installed on the bridge. Most of the proposed methods are based on the identification of dynamic characteristics of the bridge from responses measured on the vehicle, such as natural frequency, mode shapes, and damping. In addition, some of the methods seek to directly detect bridge damage based on the interaction between the vehicle and bridge. This paper presents a critical review of indirect methods for bridge monitoring and provides discussion and recommendations on the challenges to be overcome for successful implementation in practice.

  10. Polymeric salt bridges for conducting electric current in microfluidic devices

    Science.gov (United States)

    Shepodd, Timothy J.; Tichenor, Mark S.; Artau, Alexander

    2009-11-17

    A "cast-in-place" monolithic microporous polymer salt bridge for conducting electrical current in microfluidic devices, and methods for manufacture thereof is disclosed. Polymeric salt bridges are formed in place in capillaries or microchannels. Formulations are prepared with monomer, suitable cross-linkers, solvent, and a thermal or radiation responsive initiator. The formulation is placed in a desired location and then suitable radiation such as UV light is used to polymerize the salt bridge within a desired structural location. Embodiments are provided wherein the polymeric salt bridges have sufficient porosity to allow ionic migration without bulk flow of solvents therethrough. The salt bridges form barriers that seal against fluid pressures in excess of 5000 pounds per square inch. The salt bridges can be formulated for carriage of suitable amperage at a desired voltage, and thus microfluidic devices using such salt bridges can be specifically constructed to meet selected analytical requirements.

  11. Evaluating the life cycle environmental impact of short span bridges

    DEFF Research Database (Denmark)

    Du, Guangli; Pettersson, Lars; Karoumi, Raid

    2016-01-01

    Bridge infrastructure consumes large amount of energy and raw materials, leading to considerable environmental burdens. The traditional infrastructure construction prioritizes its technical and economic viability. In recent years, the society devotes an ever-increased attention to the environmental...... impact of the construction sector. Life cycle assessment (LCA) is a systematic method for assessing the environmental impact of products and systems, but its application in bridges is scarce. In Swede, most of the bridges are short spans and the type of concrete slab-frame bridge (CFB) accounts...... for a large share. Soil steel composite bridge (SSCB) is a functional equivalent solution for CFB. In order to mitigate the environmental burdens of short span bridges, this paper performed a comparative LCA study between these two types of bridge. The results indicate that the initial material consumption...

  12. Online Bridge Crack Monitoring with Smart Film

    Directory of Open Access Journals (Sweden)

    Benniu Zhang

    2013-01-01

    Full Text Available Smart film crack monitoring method, which can be used for detecting initiation, length, width, shape, location, and propagation of cracks on real bridges, is proposed. Firstly, the fabrication of the smart film is developed. Then the feasibility of the method is analyzed and verified by the mechanical sensing character of the smart film under the two conditions of normal strain and crack initiation. Meanwhile, the coupling interference between parallel enameled wires of the smart film is discussed, and then low-frequency detecting signal and the custom communication protocol are used to decrease interference. On this basis, crack monitoring system with smart film is designed, where the collected crack data is sent to the remote monitoring center and the cracks are simulated and recurred. Finally, the monitoring system is applied to six bridges, and the effects are discussed.

  13. Fatigue-Prone Details in Steel Bridges

    Directory of Open Access Journals (Sweden)

    Mohsen Heshmati

    2012-11-01

    Full Text Available This paper reviews the results of a comprehensive investigation including more than 100 fatigue damage cases, reported for steel and composite bridges. The damage cases are categorized according to types of detail. The mechanisms behind fatigue damage in each category are identified and studied. It was found that more than 90% of all reported damage cases are of deformation-induced type and generated by some kind of unintentional or otherwise overlooked interaction between different load-carrying members or systems in the bridge. Poor detailing, with unstiffened gaps and abrupt changes in stiffness at the connections between different members were also found to contribute to fatigue cracking in many details.

  14. Accelerated aging of polymer composite bridge materials

    Science.gov (United States)

    Carlson, Nancy M.; Blackwood, Larry G.; Torres, Lucinda L.; Rodriguez, Julio G.; Yoder, Timothy S.

    1999-05-01

    Accelerated aging research on samples of composite materials and candidate UV protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory. Durability results and sensor data form test with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards and acceptance criteria for PMC bridges for use in the transportation infrastructure.

  15. Skin bridging secondary to ingrown toenail.

    Science.gov (United States)

    Dadaci, Mehmet; Ince, Bilsev; Altuntas, Zeynep; Kamburoglu, Haldun Onuralp; Bitik, Ozan

    2014-01-01

    Ingrown toenails are painful conditions that especially affect young people and may become chronic if not treated. We describe a case of chronically inflamed ingrown toenail left untreated for three years. In the physical examination, skin bridging and epithelialization was observed in midline secondary to soft tissue hypertrophy of the lateral nail matrixes. Epithelized fibrous tissue was cut across the lateral nail matrix and left for secondary healing. Partial matrixectomy was applied and the remnants were cauterized in compliance with the Winograd procedure after removal of the nail. Our case is an advanced condition which is the second report in the literature. Skin bridging secondary to excess soft tissue hypertrophy can be observed in untreated bilateral Heinfert or Frost stage 3 ingrown nails. This rare case can be classified as advanced stage 3 disease or stage 4.

  16. Accelerated Aging of Polymer Composite Bridge Materials

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Nancy Margaret; Blackwood, Larry Gene; Torres, Lucinda Laine; Rodriguez, Julio Gallardo; Yoder, Timothy Scott

    1999-03-01

    Accelerated aging research on samples of composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory (INEEL). Durability results and sensor data from tests with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards, and acceptance criteria for PMC bridges for use in the transportation infrastructure.

  17. A liquid bridge connecting moving porous surfaces

    Science.gov (United States)

    Gharib, Morteza; Gat, Amir; Navaz, Homayun

    2011-11-01

    We study the coupled problem of a liquid bridge connecting two porous surfaces where the gap between the surfaces is an externally controlled function of time. The relative motion between the surfaces affects the geometry and the pressure distribution of the liquid bridge, thus influencing the diffusion speed and penetration topology within the porous material. Utilizing the lubrication approximation and Darcy's phenomenological law we obtain a relation between the diffusion into the porous surface and the relative motion between the surfaces. A scheme to control the diffusion topology is presented and illustrated for the case of conical penetration topology with an arbitrary cone opening angle. Analytic expressions describing the penetration topology for the case of constant speed of the surfaces and the relative motion between the surfaces required to create a conical penetration topology are obtained and compared to experimental and numerical data. This project was supported by the Defense Threat Reduction Agency (DTRA), Award Number: 330233-A.

  18. Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration

    OpenAIRE

    Yongle Li; Shifu Dong; Yulong Bao; Kejian Chen; Shizhong Qiang

    2015-01-01

    Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehi...

  19. Skin bridging secondary to ingrown toenail

    OpenAIRE

    Dadaci, Mehmet; Ince, Bilsev; Altuntas, Zeynep; Kamburoglu, Haldun Onuralp; Bitik, Ozan

    2014-01-01

    Ingrown toenails are painful conditions that especially affect young people and may become chronic if not treated. We describe a case of chronically inflamed ingrown toenail left untreated for three years. In the physical examination, skin bridging and epithelialization was observed in midline secondary to soft tissue hypertrophy of the lateral nail matrixes. Epithelized fibrous tissue was cut across the lateral nail matrix and left for secondary healing. Partial matrixectomy was applied and ...

  20. Bridging the Gap: Linking Simulation and Testing

    Energy Technology Data Exchange (ETDEWEB)

    Krajewski, Paul E.; Carsley, John; Stoudt, Mark R.; Hovanski, Yuri

    2012-09-01

    The Materials Genome Initiative (MGI) which is a key enabler for the Advanced Manufacturing Partnership, announced in 2011 by U.S. President Barack Obama, was established to accelerate the development and deployment of advanced materials. The MGI is driven by the need to "bridge the gap" between (I) experimental results and computational analysis to enable the rapid development and validation of new mateirals, and (II) the processes required to convert these materials into useable goods.

  1. COLLISIONS OF ROAD VEHICLES WITH BRIDGE COLUMNS

    OpenAIRE

    2015-01-01

    As speed limits and traffic on city roads continue to increase, collisions between road vehicles and bridge columns are becoming more common. Current regulations analyze collision with one major simplification: replacing dynamic action with the equivalent static force. In the present paper, we develop a numerical model of a typical Croatian overpass and loaded it with an equivalent static load according to the EN1991-7 and ASSHTO LRFD provisions, analyzing the differences in overpass behavior...

  2. Structural characterization of thioether-bridged bacteriocins.

    Science.gov (United States)

    Lohans, Christopher T; Vederas, John C

    2014-01-01

    Bacteriocins are a group of ribosomally synthesized antimicrobial peptides produced by bacteria, some of which are extensively post-translationally modified. Some bacteriocins, namely the lantibiotics and sactibiotics, contain one or more thioether bridges. However, these modifications complicate the structural elucidation of these bacteriocins using conventional techniques. This review will discuss the techniques and strategies that have been applied to determine the primary structures of lantibiotics and sactibiotics. A major challenge is to identify the topology of thioether bridges in these peptides (i.e., which amino-acid residues are involved in which bridges). Edman degradation, NMR spectroscopy and tandem MS have all been commonly applied to characterize these bacteriocins, but can be incompatible with the post-translational modifications present. Chemical modifications to the modified residues, such as desulfurization and reduction, make the treated bacteriocins more compatible to analysis by these standard peptide analytical techniques. Despite their differences in structure, similar strategies have proved useful to study the structures of both lantibiotics and sactibiotics.

  3. Communication through molecular bridges: different bridge orbital trends result in common property trends.

    Science.gov (United States)

    Proppe, Jonny; Herrmann, Carmen

    2015-02-05

    Common trends in communication through molecular bridges are ubiquitous in chemistry, such as the frequently observed exponential decay of conductance/electron transport and of exchange spin coupling with increasing bridge length, or the increased communication through a bridge upon closing a diarylethene photoswitch. For antiferromagnetically coupled diradicals in which two equivalent spin centers are connected by a closed-shell bridge, the molecular orbitals (MOs) whose energy splitting dominates the coupling strength are similar in shape to the MOs of the dithiolated bridges, which in turn can be used to rationalize conductance. Therefore, it appears reasonable to expect the observed common property trends to result from common orbital trends. We illustrate based on a set of model compounds that this assumption is not true, and that common property trends result from either different pairs of orbitals being involved, or from orbital energies not being the dominant contribution to property trends. For substituent effects, an effective modification of the π system can make a comparison difficult.

  4. Development of bridge management system (BMS); Bridge Management System (BMS) no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, A.; Kushida, M. [Yamaguchi University, Yamaguchi (Japan). Faculty of Engineering; Adachi, Y. [Hanshin Expressway Public Corp., Osaka (Japan); Matsumoto, M. [Kobe University, Kobe (Japan)

    1997-03-20

    With an objective to develop a bridge management system (BMS) which can execute overall management of road networks, discussions were given on the subject taking advantage of a result of the output from a concrete bridge diagnosis expert system. As its first step, a certain bridge was noticed to discuss an optimal maintenance and management measure which takes into consideration the safety, economic efficiency, functionality, and environmentality. The system has made it possible to estimate deterioration of the bridge after repair and reinforcement by proposing a deterioration curve and setting different hypotheses as a method to forecast performance deterioration of bridge members. Necessity of repair and reinforcement at the time of checking was determined from the result of an output from the expert system to select a construction method. A scheduled number of service years is set, all of the combinations of maintenance and management measures which satisfy the scheduled service life were retrieved, and an optimal maintenance and management measure was indicated, whose total cost is minimum among the proposed measures. Applying this MBS is capable to some extent of evaluating the effect of executing different measures and making economical optimization. 15 refs., 12 figs., 18 tabs.

  5. Building water bridges in air: Electrohydrodynamics of the Floating Water Bridge

    CERN Document Server

    Marin, Alvaro G

    2010-01-01

    The interaction of electrical fields and liquids can lead to phenomena that defies intuition. Some famous examples can be found in Electrohydrodynamics as Taylor cones, whipping jets or non-coalescing drops. A less famous example is the Floating Water Bridge: a slender thread of water held between two glass beakers in which a high voltage difference is applied. Surprisingly, the water bridge defies gravity even when the beakers are separated at distances up to 2 cm. In the presentation, experimental measurements and simple models are proposed and discussed for the stability of the bridge and the source of the flow, revealing an important role of polarization forces on the stability of the water bridge. On the other hand, the observed flow can only be explained due to the non negligible free charge present in the surface. In this sense, the Floating Water Bridge can be considered as an extreme case of a leaky dielectric liquid (J. R. Melcher and G. I. Taylor, Annu. Rev. Fluid Mech., 1:111, 1969).

  6. 金沙江白鹤滩水电站葫芦口大桥主桥设计%Design of Main Bridge of Hulukou Bridge Crossing Chin-sha River at Baihetan Hydropower Station

    Institute of Scientific and Technical Information of China (English)

    康晋; 舒思利; 徐恭义

    2015-01-01

    葫芦口大桥主桥为(158+656+145) m的单跨双铰钢桁梁悬索桥。该桥设2根主缆,主缆采用预制平行高强钢丝索股结构。全桥共布置71对吊索,吊索采用预制平行钢丝束,与索夹采用销轴连接方式。主索鞍为全铸式结构,鞍底设置滑动副。散索鞍为底座式结构,下设滚轴支座。主缆锚固系统采用型钢锚固系统。加劲梁采用钢桁梁,桁高4.5m,宽17m,采用钢混组合桥面系。两岸锚碇均采用重力式锚、现浇扩大基础,其中巧家侧锚碇采用明挖嵌岩基础。桥塔为钢筋混凝土门式框架结构,塔柱竖直布置,基础采用直径2.5 m的钻孔灌注桩。采用有限元软件BNLAS及MIDAS对该桥进行计算分析,结果表明该桥的静力、动力特性均满足规范要求。%The main bridge of the Hulukou Bridge is a single span double‐hinge steel truss girder suspension bridge with span arrangement of(158+656+145) m .The bridge has two main cables made up of prefabricated parallel high‐strength steel wires .A total of 71 hanger cables , which are composed of prefabricated parallel steel wire strands and are connected with the cable clamps by pin connection ,are installed .The tower saddles are fully‐cast structures ,on the base of w hich sliding pairs are added ,and the spray saddles are pedestal‐like structures resting on roller bearings .The anchoring systems for the main cables are the section steel anchoring system .The stiffening girder adopts the steel truss girder which is 4 .5 m high and 17 m wide ,covered by the steel‐concrete composite deck .The anchorages on the two banks of the river are gravity anchors , the foundation of one anchor is the cast‐in‐situ spread foundation ,w hile the other on the Qiaojia side the open‐cut foundation embedded in rocks .The towers are reinforced concrete portal frame structures with vertical columns ,the foundations of which are formed of 2 .5 m diameter

  7. The Internet Inter-Orb Protocol Security Bridge

    Directory of Open Access Journals (Sweden)

    Pawel Slowikowski

    1999-01-01

    Full Text Available In this paper, we present a security bridge for the Internet protocol of interoperability amongst CORBA objects and the Internet inter-ORB Protocol (IIOP. The bridge helps in making accessible objects in the Internet and makes possible the access control to them. The bridge was realized in the popular request broker the Visigenic's VisiBroker under Windows 95/NT and Solaris 2.X operating systems. We describe two ways of locating the bridge in the request broker. The first means uses one name domain of broker and is not transparent for client. The second one uses two name domains and provides objects protection on the level of the Naming Service and is transparent lor the client. We also describe the variant ofthe second means with using GateKeeper server to support IIOP tunneling within HTTP. We emphasize the importance of a firewall, cooperating with a bridge. which is required for the purpose of providing object protection. The paper presents an original conception of security managing, basing on the ideas of users, groups and resources defined using the standard terms of CORBA, IIOP and TCP/IP, that allows to control positively and negatively the access to classes (interfaces, objects and also to their individual methods. This conception was effectively implemented in a functioning bridge. Further chapters describe the foundations and some details of the bridge implementation sueli as the use ofthe Interface Repository, cache memory application, thread synchronization and the way of synchronization of the configuration applet with the bridge's objects. We discuss the influence of these solutions on the efficiency ofthe bridge and its source code portability. We also present the general structure of the component objects ofthe bridge with a scheme. ln the next part we characterize the implementation foundations ofthe bridge manager, realized as an applet in Java, with the stress on the possibility of the bridge configuration through the

  8. Disulfide Bridges: Bringing Together Frustrated Structure in a Bioactive Peptide.

    Science.gov (United States)

    Zhang, Yi; Schulten, Klaus; Gruebele, Martin; Bansal, Paramjit S; Wilson, David; Daly, Norelle L

    2016-04-26

    Disulfide bridges are commonly found covalent bonds that are usually believed to maintain structural stability of proteins. Here, we investigate the influence of disulfide bridges on protein dynamics through molecular dynamics simulations on the cysteine-rich trypsin inhibitor MCoTI-II with three disulfide bridges. Correlation analysis of the reduced cyclic peptide shows that two of the three disulfide distances (Cys(11)-Cys(23) and Cys(17)-Cys(29)) are anticorrelated within ∼1 μs of bridge formation or dissolution: when the peptide is in nativelike structures and one of the distances shortens to allow bond formation, the other tends to lengthen. Simulations over longer timescales, when the denatured state is less structured, do not show the anticorrelation. We propose that the native state contains structural elements that frustrate one another's folding, and that the two bridges are critical for snapping the frustrated native structure into place. In contrast, the Cys(4)-Cys(21) bridge is predicted to form together with either of the other two bridges. Indeed, experimental chromatography and nuclear magnetic resonance data show that an engineered peptide with the Cys(4)-Cys(21) bridge deleted can still fold into its near-native structure even in its noncyclic form, confirming the lesser role of the Cys(4)-Cys(21) bridge. The results highlight the importance of disulfide bridges in a small bioactive peptide to bring together frustrated structure in addition to maintaining protein structural stability.

  9. Aerodynamic stability of cable-supported bridges using CFRP cables

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-jun; YING Lei-dong

    2007-01-01

    To gain understanding of the applicability of carbon fiber reinforced polymer (CFRP) cable in cable-supported bridges, based on the Runyang Bridge and Jinsha Bridge, a suspension bridge using CFRP cables and a cable-stayed bridge using CFRP stay cables are designed, in which the cable's cross-sectional area is determined by the principle of equivalent axial stiffness.Numerical investigations on the aerodynamic stability of the two bridges are conducted by 3D nonlinear aerodynamic stability analysis. The results showed that as CFRP cables are used in cable-supported bridges, for suspension bridge, its aerodynamic stability is superior to that of the case using steel cables due to the great increase of the torsional frequency; for cable-stayed bridge,its aerodynamic stability is basically the same as that of the case using steel stay cables. Therefore as far as the wind stability is considered, the use of CFRP cables in cable-supported bridges is feasible, and the cable's cross-sectional area should be determined by the principle of equivalent axial stiffness.

  10. Field Tests and Simulation of Lion-Head River Bridge

    Directory of Open Access Journals (Sweden)

    Yao-Min Fang

    2007-01-01

    Full Text Available Lion-Head River Bridge is a twin bridge in parallel position. The east-bounded was designed and constructed as a traditional prestress concrete box girder bridge with pot bearings; and the west-bounded was installed with seismic isolation devices of lead rubber bearings. The behavior of the isolated bridge is compared with that of the traditional bridge through several field tests including the ambient vibration test, the force vibration test induced by shakers, the free vibration test induced by a push and fast release system, and the truck test. The bridges suffered from various extents of damage due to the Chi-Chi and the Chi-I earthquakes of great strength during the construction and had been retrofitted. The damage was reflected by the change of the bridges' natural frequencies obtained from the ambient vibration tests. The models of the two bridges are simulated by the finite element method based on the original design drawings. Soil-structure interaction was also scrutinized in this study. The simulation was then modified based on the results from the field tests. Dynamic parameters of bridges are identified and compared with those from theoretical simulation. The efficiency is also verified to be better for an isolated bridge.

  11. Bridges analysis, design, structural health monitoring, and rehabilitation

    CERN Document Server

    Bakht, Baidar

    2015-01-01

    This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

  12. A cloud-based information repository for bridge monitoring applications

    Science.gov (United States)

    Jeong, Seongwoon; Zhang, Yilan; Hou, Rui; Lynch, Jerome P.; Sohn, Hoon; Law, Kincho H.

    2016-04-01

    This paper describes an information repository to support bridge monitoring applications on a cloud computing platform. Bridge monitoring, with instrumentation of sensors in particular, collects significant amount of data. In addition to sensor data, a wide variety of information such as bridge geometry, analysis model and sensor description need to be stored. Data management plays an important role to facilitate data utilization and data sharing. While bridge information modeling (BrIM) technologies and standards have been proposed and they provide a means to enable integration and facilitate interoperability, current BrIM standards support mostly the information about bridge geometry. In this study, we extend the BrIM schema to include analysis models and sensor information. Specifically, using the OpenBrIM standards as the base, we draw on CSI Bridge, a commercial software widely used for bridge analysis and design, and SensorML, a standard schema for sensor definition, to define the data entities necessary for bridge monitoring applications. NoSQL database systems are employed for data repository. Cloud service infrastructure is deployed to enhance scalability, flexibility and accessibility of the data management system. The data model and systems are tested using the bridge model and the sensor data collected at the Telegraph Road Bridge, Monroe, Michigan.

  13. Construction and control technology of the main bridge superstructure of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Hong; Luo Chenbin; Zhang Yongtao; You Xinpeng

    2009-01-01

    The Sutong Yangtze River Bridge (short as Sutong Bridge) is now the largest span cable-stayed bridge in the world. The construction of the superstructure of the middle bridge covered several stages including erection of the big block girders for the side span, assistant span and tower area, erection of standard girders and closure of the middle span. The big block girders were hoisted by a floating crane, and the standard girders were hoisted by a double crane system on the deck. The pushing assistant method was adopted for the middle span closure construction. Furthermore, key technologies and innovative methods used in the processes of girder erection and cable assemblage in all stages were expatiated systematically. An all-stage self- adaptive geometry control method was used in the construction process. By accurately controlling the unstressed dimensions and shape of all structural components in each step, and realization that the control system and the controlled system adapt to each other, the goal was to make control of the final line shape and inner force of the bridge structure achievable. Two solutions, including GPS based and total station based dynamic geometry monitoring systems, were used to resolve the measure problem under the wide-range of wind-induced vibrations in the long cantilever state. Finally, research on the wind-induced vibration of the superstructure during the construction period was executed. Buffeting response analysis to the longest single and double cantilever states were carried out. The analysis and evaluation of wind resistance safety of the main girders under the longest single cantilever state was made, and corresponding wind resistance measures were suggested. The as-built geometric error and cable force error were controlled in a required design range, and this whole technological achievement can be a benchmark for construction of other large span cable-stayed bridges in the future.

  14. 鄂东长江大桥施工过程非线性稳定性分析%Stability Analysis of Edong Yangtze River Bridge during Construction

    Institute of Scientific and Technical Information of China (English)

    赵雷; 孙才志; 杨兴旺

    2012-01-01

    为探讨大跨度混合梁斜拉桥施工过程中结构非线性稳定性的变化规律及其影响因素,以鄂东长江大桥为研究对象,按照结构型式及施工工序的特点,采用LSB和ANSYS有限元软件计算大桥施工过程非线性稳定安全系数并获得结构失稳形态,分析了非线性因素对静力稳定性的影响规律.此外,探讨了混合梁斜拉桥设计与施工工程参数——钢混结合部位置、索梁锚固方式、施工临时荷载及横向风荷载与大桥施工过程非线性稳定性的关系.结果表明,上述工程参数对施工过程非线性稳定性有不同程度的影响,但总体上并非其控制性因素.%In order to research the change law of non-linear stability and its influencing factors of a long-span composite cable-stayed bridge during construction, by taking Edong Yangtze River bridge as research subject, LSB and ANSYS models were built based on the structure type and construction sequence of the bridge to calculate the non-linear stability safety factors during bridge construction and obtain the instability mode. The influencing law of non-linear factors to static stability was analyzed. In addition, the relationships among the stability during construction and steel-concrete connection position, cable-beam anchorage mode, temporary construction loads and cross-wind load were investigated. The research results show that the above factors have different effects on the stability during construction, but they are not controlling factors.

  15. Investigation of Aerodynamic Interference of Double Deck Bridges

    Energy Technology Data Exchange (ETDEWEB)

    Sitek, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC)

    2016-05-01

    Construction of a twin bridge can be a cost effective and minimally disruptive way to increase capacity when an existing bridge is not near the end of its service life. With ever growing vehicular traffic, when demand approaches the capacity of many existing roads and bridges. Remodeling a structure with an insufficient number of lanes can be a good solution in case of smaller and less busy bridges. Closing down or reducing traffic on crossings of greater importance for the construction period, however, can result in major delays and revenue loss for commerce and transportation as well as increasing the traffic load on alternate route bridges. Multiple-deck bridges may be the answer to this issue. A parallel deck can be built next to the existing one, without reducing the flow. Additionally, a new bridge can be designed as a twin or multi-deck structure. Several such structures have been built throughout the United States, among them: - The New NY Bridge Project - the Tappan Zee Hudson River Crossing, - SR-182 Columbia River Bridge, - The Thaddeus Kosciusko Bridge (I-87), - The Allegheny River Bridge, Pennsylvania, which carries I76, - Fred Hartman Bridge, TX, see Figure 1.2. With a growing number of double deck bridges, additional, more detailed, studies on the interaction of such bridge pairs in windy conditions appears appropriate. Aerodynamic interference effects should be examined to assure the aerodynamic stability of both bridges. There are many studies on aerodynamic response of single deck bridges, but the literature on double-deck structures is not extensive. The experimental results from wind tunnels are still limited in number, as a parametric study is required, they can be very time consuming. Literature review shows that some investigation of the effects of gap-width and angle of wind incidence has been done. Most of the CFD computational studies that have been done were limited to 2D simulations. Therefore, it is desirable to investigate twin decks

  16. Wind Tunnel Experiments with Active Control of Bridge Section Model

    DEFF Research Database (Denmark)

    Hansen, Henriette I.; Thoft-Christensen, Palle

    the flutter wind velocity for future ultra-long span suspension bridges. The purpose of the wind tunnel experiments is to investigate the principle to use this active flap control system. The bridge section model used in the experiments is therefore not a model of a specific bridge but it is realistic......This paper describes results of wind tunnel experiments with a bridge section model where movable flaps are integrated in the bridge girder so each flap is the streamlined part of the edge of the girder. This active control flap system is patented by COWIconsult and may be used to increase...... compared with a real bridge. Five flap configurations are investigated during the wind tunnel experiments and depending on the actual flap configuration it is possible to decrease or increase the flutter wind velocity for the model....

  17. Measurements of bridges' vibration characteristics using a mobile phone

    Directory of Open Access Journals (Sweden)

    Z. M. C. Pravia

    Full Text Available ABSTRACTThis research presents an alternative way to perform a bridge inspection, which considers the dynamics parameters from the structure. It shows an experimental phase with use of a mobile phone to extract the accelerations answers from two concrete bridges, from those records is feasible to obtain natural frequencies using the Fast Fourier Transform (FFT.Numerical models with uses finite element model (FEM allow to determine the natural frequencies from the two concrete bridges and compare with the experimental phase of each one. The final results shows it's possible to use mobiles phones to extract vibration answers from concrete bridges and define the structural behavior of bridges from natural frequencies, this procedure could be used to evaluate bridges with lower costs.

  18. Detection of Subsurface Defects in Concrete Bridge Deck Joints

    Directory of Open Access Journals (Sweden)

    Wonchang Choi

    2011-01-01

    Full Text Available Problem statement: The integrity of deck joints in highway bridges plays a major role to determine overall performance of bridge system. As the bridge maintenance program, the defects in deck joints have historically been detected by conventional non-destructive testing and evaluation methods such as visual inspection, chain-dragging and by the detecting sounds under the traffic. Future bridge maintenance challenges will demand the development of techniques and procedures to detect and monitor such defects before they become apparent. Approach: Two non-destructive methods; namely Ground Penetration Radar (GPR and Seismic Properties Analyzer (SPA were employed to assess the integrity of deck joins installed in North Carolina bridges. Results: The results obtained with the GPR and SPA allows to quantify the subsurface defects in bridge deck joints. Conclusion: The practical application and limitations of each method are discussed in this study.

  19. Structural safety monitoring for Nanjing Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    黄方林; 何旭辉; 陈政清; 曾储惠

    2004-01-01

    In order to evaluate objectively and accurately the integrity, safety and operating conditions in real time for the Nanjing Yangtze River Bridge, a large structural safety monitoring system was described. The monitoring system is composed of three parts: sensor system, signal sampling and processing system, and safety monitoring and assessment system. Combining theoretical analysis with measured data analysis, main monitoring contents and layout of measuring points were determined. The vibration response monitoring was significantly investigated. The main contents of safety monitoring on vibration response monitoring are vibration of the main body of the Nanjing Yangtze river bridge, collision avoidance of the bridge piers, vibration of girders on high piers for the bridge approach and earthquake. As a field laboratory, the safety monitorying system also provides information to investigate the unknown and indeterminate problems on bridge structures and specific environment around bridges.

  20. CFRP筋锚固体系研究与应用现状%Research and Application Situation of CFRP Tendon Anchorage System

    Institute of Scientific and Technical Information of China (English)

    刘荣桂; 李明君; 蔡东升; 刘德鑫

    2012-01-01

    为促进碳纤维增强复合材料(CFRP)这一具有密度小、抗拉强度高、抗疲劳、耐腐蚀等特性材料的研究工作与在土木工程结构中的实际应用,主要介绍了各国有关CFRP筋及其锚具研究和应用的最新进展,分别对粘结型、夹片型、复合型3类现有的主要类型锚具的锚固机理、代表性试验研究和数值分析等方面做了整理和归纳,并提出了锚具开发和应用的一些关键问题和建议.%In order to promote the future research and application of carbon fiber reinforced polymer (CFRP) for civil engineering structures, with the characteristics of low specific gravity, high tensile strength, high fatigue resistance and corrosion resistance, an introduction was given on the latest research and application progress of CFRP tendon and anchors for all countries. The anchorage mechanism, typical experiment investigations and numerical analysis of exist main types of anchors, including bond-type anchor, wedge-type anchor and wedge-bond anchor, were also classified and summarized. Finally, some critical problems and advices in anchor development and utilization were provided.

  1. Doxycycline-Regulated p16(MTS1) Expression Suppresses the Anchorage-Independence and Tumorigenicity of Breast Cancer Cell Lines that Lack Endogenous p16.

    Science.gov (United States)

    Todd, Maria C; Langan, Thomas A; Sclafani, Robert A

    2017-01-01

    The RB pathway controls the critical transition from G1 into S phase of the mammalian cell cycle. Deregulation of the RB pathway by means of RB or p16 inactivation has been implicated in the development of virtually all human cancers. Such findings have led to the view that the loss of RB-mediated regulation at the G1/S checkpoint is a precondition for human malignancy. Our analysis of the RB-positive MCF-7 and ZR75.1 breast cancer cell lines revealed a lack of endogenous p16 protein expression as a result of the homozygous deletion and methylation of the p16 gene at the CDKN2A locus, respectively. We employed the TET-OFF inducible expression system to investigate the effects of non-growth inhibitory levels of functional p16 protein upon the in vitro and in vivo transformed properties of the MCF-7 and ZR75.1 cell lines. Stable transfectants of MCF-7 and ZR75.1 cells were isolated that expressed different levels of p16 protein in the absence of doxycycline (DOX) but continued to proliferate in culture. Transfectants that expressed modest levels of p16 (relative to SV40 T antigen-transformed HBL-100 breast epithelial cells) demonstrated a marked suppression of anchorage-independent growth in soft agar. Further, the induction of moderate and high levels of p16 (relative to HBL-100) resulted in the suppression of tumorigenicity of both MCF-7 and ZR75.1 cells as assayed by injection into nude mice. From these data, we concluded that RB pathway restoration by non-growth inhibitory levels of p16 protein was sufficient to revert breast cancer cells to a non-transformed and non-tumorigenic state.

  2. Doxycycline-Regulated p16MTS1 Expression Suppresses the Anchorage-Independence and Tumorigenicity of Breast Cancer Cell Lines that Lack Endogenous p16

    Science.gov (United States)

    Todd, Maria C; Langan, Thomas A; Sclafani, Robert A

    2017-01-01

    The RB pathway controls the critical transition from G1 into S phase of the mammalian cell cycle. Deregulation of the RB pathway by means of RB or p16 inactivation has been implicated in the development of virtually all human cancers. Such findings have led to the view that the loss of RB-mediated regulation at the G1/S checkpoint is a precondition for human malignancy. Our analysis of the RB-positive MCF-7 and ZR75.1 breast cancer cell lines revealed a lack of endogenous p16 protein expression as a result of the homozygous deletion and methylation of the p16 gene at the CDKN2A locus, respectively. We employed the TET-OFF inducible expression system to investigate the effects of non-growth inhibitory levels of functional p16 protein upon the in vitro and in vivo transformed properties of the MCF-7 and ZR75.1 cell lines. Stable transfectants of MCF-7 and ZR75.1 cells were isolated that expressed different levels of p16 protein in the absence of doxycycline (DOX) but continued to proliferate in culture. Transfectants that expressed modest levels of p16 (relative to SV40 T antigen-transformed HBL-100 breast epithelial cells) demonstrated a marked suppression of anchorage-independent growth in soft agar. Further, the induction of moderate and high levels of p16 (relative to HBL-100) resulted in the suppression of tumorigenicity of both MCF-7 and ZR75.1 cells as assayed by injection into nude mice. From these data, we concluded that RB pathway restoration by non-growth inhibitory levels of p16 protein was sufficient to revert breast cancer cells to a non-transformed and non-tumorigenic state.

  3. Smart suspension systems for bridge-friendly vehicles

    Science.gov (United States)

    Chen, Yonghong; Tan, Chin An; Bergman, Larry A.; Tsao, T. C.

    2002-06-01

    In this paper, the effects of using semi-active control strategy (such as MR dampers) in vehicle suspensions on the coupled vibrations of a vehicle traversing a bridge are examined in order to develop various designs of smart suspension systems for bridge-friendly vehicles. The bridge-vehicle coupled system is modeled as a simply supported beam traversed by a two-degree-of-freedom quarter-car model. The surface unevenness on the bridge deck is modeled as a deterministic profile of a sinusoidal wave. As the vehicle travels along the bridge, the system is excited as a result of the surface unevenness and this excitation is characterized by a frequency defined by the speed of travel and the wavelength of the profile. The dynamic interactions between the bridge and the vehicle due to surface deck irregularities are obtained by solving the coupled equations of motion. Numerical results of a passive control strategy show that, when the lower natural frequency of the vehicle matches with a natural frequency (usually the first frequency) of the bridge and the excitation frequency, the maximum response of the bridge is large while the response of the vehicle is relatively smaller, meaning that the bridge behaves like a vibration absorber. This is undesirable from a bridge design viewpoint. Comparative studies of passive and semi-active controls for the vehicle suspension are performed. It is demonstrated that skyhook control can significantly mitigate the response of the bridge, while ground-hook control reduces the tire force impacted onto the bridge.

  4. Global Bridges: building an international network for tobacco dependence treatment

    Directory of Open Access Journals (Sweden)

    Katie Kemper

    2016-03-01

    Full Text Available Global Bridges, hosted at Mayo Clinic, is the most diverse international network of healthcare professionals dedicated to tobacco dependence treatment. Global Bridges works with grantees and partners in all six WHO regions to educate healthcare providers on evidence-based treatment and advocate for effective tobacco policy. This session will describe accomplishments and lessons learned in the Global Bridges program over nearly six years, and opportunities to better integrate cessation support into comprehensive tobacco control.

  5. A NEW APPROACH OF DIGITAL BRIDGE SURFACE MODEL GENERATION

    OpenAIRE

    Ju, H.

    2012-01-01

    Bridge areas present difficulties for orthophotos generation and to avoid “collapsed” bridges in the orthoimage, operator assistance is required to create the precise DBM (Digital Bridge Model), which is, subsequently, used for the orthoimage generation. In this paper, a new approach of DBM generation, based on fusing LiDAR (Light Detection And Ranging) data and aerial imagery, is proposed. The no precise exterior orientation of the aerial image is required for the DBM generation. First, a co...

  6. Bridges of the sella turcica - anatomy and topography.

    Science.gov (United States)

    Skrzat, Janusz; Mroz, Izabela; Marchewka, Justyna

    2012-01-01

    This paper presents anatomy and topography of the inconstant osseous bridges that may occur in the sella turcica region. The interclinoid bridge and the caroticoclinoid bridge can be formed in consequence of abnormal ossification of the dural folds or disturbances in development of the sphenoid bone. Their presence may be of clinical importance because of potential influence on the neurovascular structures passing in the vicinity of the clinoid processes of the sphenoid bone.

  7. Commutation Processes in Multiresonant ZVS Bridge Converter

    Directory of Open Access Journals (Sweden)

    Miroslaw Luft

    2008-01-01

    Full Text Available The analysis of the multiresonant ZVS DC/DC bridge converter is presented. The control system of the converter is basedon the method of frequency control at the constant time of transistor turn-off with a phase shift. The operation of the circuit is givenand the operating range of the converter is defined where ZVS switching operation is assured. Control characteristics are given andthe converter’s efficiency is defined. The circuit’s operation is analysed on the basis of results of the converter simulation tests using Simplorer programme.

  8. Fatigue Performance of Bridge Deck Pavement Materials

    Institute of Scientific and Technical Information of China (English)

    WU Shaopeng; ZHANG Guang; HAN Jun; LIU Gang; ZHOU Jie

    2009-01-01

    Three beam samplesof bridge deck pavementwere prepared, with gradationtypes of AC-13, and AC-16 and combined AC-13+AC-16. Four-point bending test was adopted to investigate the fatigue performance of these beam samples. The experimental results indicate that the initial bending stiffness is related to the type of beam sample and testing temperature. Fatigue life of these samples decreases as the increase of the controlled strain level. The AC-13 beam sample exhibits better fatigue resistance and bigger limiting bending strain at the given strain level and temperature. Com-pared with single beam sample, the fatigue performance of combining beam sample is relatively poor.

  9. NDE of composite seismic retrofits to bridges

    Science.gov (United States)

    Johnson, E. C.; Nokes, J. P.; Hawkins, G. F.

    1999-12-01

    Composite materials are being used for bridge column seismic retrofits and to rehabilitate other concrete structures. There are three different manufacturing methods for applying composites to concrete columns which are outlined in this paper. Each method has the potential for creating debonds at the composite-concrete interface and within the composite itself. Thermography is a non-destructive evaluation technique which can be used to image debonds below the composite surface. Data from thermographic tests of a variety of retrofit applications, which include examples for each of the three aforementioned manufacturing processes, are presented.

  10. Comparison of Temperature Loadings of Bridge Girders

    Directory of Open Access Journals (Sweden)

    J. Římal

    2008-01-01

    Full Text Available This paper compares the effect of temperature changes on the superstructure of bridges, above all the effect of non-uniform temperature. Loadings according to standards ESN 73 6203, ENV 1991-1-5 and DIN 1072 are compared here. The paper shows a short summary of temperature loading according to each standard and shows the comparison of bending moments arisen from these temperature loadings on superstructure made from continuous girder from a steel-concrete box girder with a composite concrete slab. With respect to a variety of design processes, the comparison is made without any coefficient of loading, combination or material. 

  11. Structural health monitoring of bridges in the State of Connecticut

    Institute of Scientific and Technical Information of China (English)

    Chengyin Liu; Joshua Olund; Alan Cardini; Paul D'Attilio; Erie Feldblum; John DeWolf

    2008-01-01

    A joint effort between the Connecticut Department of Transportation and the University of Connecticut has been underway for more than 20 years to utilize various structural monitoring approaches to assess different bridges in Connecticut.This has been done to determine the performance of existing bridges,refine techniques needed to evaluate different bridge components,and develop approaches that can be used to provide a continuous status of a bridge's structural integrity,This paper briefly introduces the background of these studies,with emphasis on recent research and the development of structural health monitoring concepts.This paper presents the results from three different bridge types:a post-tensioned curved concrete box girder bridge,a curved steel box-girder bridge,and a steel multi-girder bridge.The structural health monitoring approaches to be discussed have been successfully tested using field data collected during multi-year monitoring periods,and are based on vibrations,rotations and strains.The goal has been to develop cost-effective strategies to provide critical information needed to manage the State of Connecticut's bridge infrastructure.

  12. International Contribution to the Highway Agency's Bridge Related Research

    DEFF Research Database (Denmark)

    Nowak, A. S.; Thoft-Christensen, Palle

    The objective of this paper is to summarize recent contributions of international experts to the research program sponsored by the Highways Agency. An efficient management of existing bridges requires methodology for an accurate evaluation of the actual loads and load carrying capacity and predic......The objective of this paper is to summarize recent contributions of international experts to the research program sponsored by the Highways Agency. An efficient management of existing bridges requires methodology for an accurate evaluation of the actual loads and load carrying capacity...... of reliability models for analysis of bridges subjected to corrosion and fatigue, and reliability-based optimization of maintenance strategies for bridges....

  13. Modulating unimolecular charge transfer by exciting bridge vibrations.

    Science.gov (United States)

    Lin, Zhiwei; Lawrence, Candace M; Xiao, Dequan; Kireev, Victor V; Skourtis, Spiros S; Sessler, Jonathan L; Beratan, David N; Rubtsov, Igor V

    2009-12-23

    Ultrafast UV-vibrational spectroscopy was used to investigate how vibrational excitation of the bridge changes photoinduced electron transfer between donor (dimethylaniline) and acceptor (anthracene) moieties bridged by a guanosine-cytidine base pair (GC). The charge-separated (CS) state yield is found to be lowered by high-frequency bridge mode excitation. The effect is linked to a dynamic modulation of the donor-acceptor coupling interaction by weakening of H-bonding and/or by disruption of the bridging base-pair planarity.

  14. Assessment of concrete bridge decks with alkali silica reactions

    DEFF Research Database (Denmark)

    Eriksen, Kirsten; Jansson, Jacob; Geiker, Mette Rica

    2008-01-01

    Based on investigations of concrete from an approximately 40 years old bridge a procedure to support the management of maintenance and repair of alkali silica damaged bridges is proposed. Combined petrography and accelerated expansion testing were undertaken on cores from the Bridge at Skovdiget......, Bagsværd, Denmark to provide information on the damage condition as well as the residual reactivity of the concrete. The Danish Road Directory’s guidelines for inspection and assessment of alkali silica damaged bridges will be briefly presented, and proposed modifications will be describe...

  15. Bridging of Calixarenes with N,N'-Bis(Chloroacetyl)Propylenediamine

    Institute of Scientific and Technical Information of China (English)

    LI Jun; WANG Wei; GONG shu-ling; CHEN Yuan-yin

    2004-01-01

    A new bridging reagent, N,N′-bis(chloroacetyl)propylenediamine was used to explore the relative activity and bridging pattern of p-tert-butylcalix[4]arene, p-tert-butylcalix[6]arene and butylcalix[8]arene. It was found that the bridging reaction is selectively, at least, preferably at 1,3-position for p-tert-butylcalix[4]arene and p-tert-butylcalix[6]arene, 1,5-position for p-tert-butylcalix[8]arene. Taking the yield of bridged calixarene as a comparsion standard, the activity decreases with the increasing of the number of phenolic units in calixarene.

  16. Research on Local Scour at Bridge Pier under Tidal Action

    Directory of Open Access Journals (Sweden)

    Wang Jianping

    2015-01-01

    Full Text Available Through the local scour test at bridge pier under tidal action in a long time series, this paper observes the growing trend of the deepest point of local scour at bridge pier under tidal conditions with different characteristic parameters, analyzes the impact of repeat sediment erosion and deposition in the scouring pit caused by reversing current on the development process of the scouring pit, and clarifies the relation between the tide and local scouring depth at bridge pier under steady flow conditions, so as to provide a scientific basis for bridge design and safe operation of estuary and harbor areas.

  17. Determination Method of Bridge Rotation Angle Response Using MEMS IMU

    Directory of Open Access Journals (Sweden)

    Hidehiko Sekiya

    2016-11-01

    Full Text Available To implement steel bridge maintenance, especially that related to fatigue damage, it is important to monitor bridge deformations under traffic conditions. Bridges deform and rotate differently under traffic load conditions because their structures differ in terms of length and flexibility. Such monitoring enables the identification of the cause of stress concentrations that cause fatigue damage and the proposal of appropriate countermeasures. However, although bridge deformation monitoring requires observations of bridge angle response as well as the bridge displacement response, measuring the rotation angle response of a bridge subject to traffic loads is difficult. Theoretically, the rotation angle response can be calculated by integrating the angular velocity, but for field measurements of actual in-service bridges, estimating the necessary boundary conditions would be difficult due to traffic-induced vibration. To solve the problem, this paper proposes a method for determining the rotation angle response of an in-service bridge from its angular velocity, as measured by a inertial measurement unit (IMU. To verify our proposed method, field measurements were conducted using nine micro-electrical mechanical systems (MEMS IMUs and two contact displacement gauges. The results showed that our proposed method provided high accuracy when compared to the reference responses calculated by the contact displacement gauges.

  18. Theoretical mechanics: Crowd synchrony on the Millennium Bridge

    Science.gov (United States)

    Strogatz, Steven H.; Abrams, Daniel M.; McRobie, Allan; Eckhardt, Bruno; Ott, Edward

    2005-11-01

    Soon after the crowd streamed on to London's Millennium Bridge on the day it opened, the bridge started to sway from side to side: many pedestrians fell spontaneously into step with the bridge's vibrations, inadvertently amplifying them. Here we model this unexpected and now notorious phenomenon - which was not due to the bridge's innovative design as was first thought - by adapting ideas originally developed to describe the collective synchronization of biological oscillators such as neurons and fireflies. Our approach should help engineers to estimate the damping needed to stabilize other exceptionally crowded footbridges against synchronous lateral excitation by pedestrians.

  19. On the identification of liquid surface properties using liquid bridges.

    Science.gov (United States)

    Kostoglou, M; Karapantsios, T D

    2015-08-01

    The term liquid bridge refers to the specific silhouette of a liquid volume when it is placed between two solid surfaces. Liquid bridges have been studied extensively both theoretically and experimentally during the last century due to their significance in many technological applications. It is worth noticing that even today new technological applications based on liquid bridges continue to appear. A liquid bridge has a well-defined surface configuration dictated by a rigid theoretical foundation so the potential of its utilization as a tool to study surface properties of liquids is apparent. However, it is very scarce in literature that the use of liquid bridges is suggested as an alternative to the well-established drop techniques (pendant/sessile drop). The present work (i) presents the theoretical background for setting up a liquid-bridge based surface property estimation problem, (ii) describes the required experimental equipment and procedures and (iii) performs a thorough literature review on the subject. A case with particular interest is that of liquid bridges made of electrically conducting liquids forming between two conducting solids; such a liquid bridge presents an integral electrical conductance value which is sensitive to the specific silhouette of the bridge. This enables the use of this integral conductance as shape descriptor instead of the conventional image processing techniques. Several attempts in literature for the estimation of liquid surface tension, liquid-solid contact angle and surfactant induced surface elasticity for conducting or non/conducting liquids are presented and the prospects of the technique are discussed.

  20. Aerodynamic stability of cable-stayed-suspension hybrid bridges

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-jun; SUN Bing-nan

    2005-01-01

    Three-dimensional nonlinear aerodynamic stability analysis was applied to study the aerodynamic stability of a cable-stayed-suspension (CSS) hybrid bridge with main span of 1400 meters, and the effects of some design parameters (such as the cable sag, length of suspension portion, cable plane arrangement, subsidiary piers in side spans, the deck form, etc.) on the aerodynamic stability of the bridge are analytically investigated. The key design parameters, which significantly influence the aerodynamic stability of CSS hybrid bridges, are pointed out, and based on the wind stability the favorable structural system of CSS hybrid bridges is discussed.

  1. Dialkylenecarbonate-Bridged Polysilsesquioxanes. Hybrid Organic Sol-Gels with a Thermally Labile Bridging Group

    Energy Technology Data Exchange (ETDEWEB)

    Loy, D.A.; Beach, J.V.; Baugher, B.M.; Assink, R.A.; Shea, K.J.; Tran, J.; Small, J.H.

    1999-04-21

    In this paper, we introduce a new approach for altering the properties of bridged polysilsesquioxane xerogels using post-processing modification of the polymeric network. The bridging organic group contains latent functionalities that can be liberated thermally, photochemically, or by chemical means after the gel has been processed to a xerogel. These modifications can produce changes in density, volubility, porosity, and or chemical properties of the material. Since every monomer possesses two latent functional groups, the technique allows for the introduction of high levels of functionality in hybrid organic-inorganic materials. Dialkylenecarbonate-bridged polysilsesquioxane gels were prepared by the sol-gel polymerization of bis(triethoxysilylpropyl)carbonate (1) and bis(triethoxysilylisobutyl)-carbonate (2). Thermal treatment of the resulting non-porous xerogels and aerogels at 300-350 C resulted in quantitative decarboxylation of the dialkylenecarbonate bridging groups to give new hydroxyalkyl and olefinic substituted polysilsesquioxane monolithic xerogels and aerogels that can not be directly prepared through direct sol-gel polymerization of organotrialkoxysilanes.

  2. The Bridge and the Troll Underneath: Summer Bridge Programs and Degree Completion

    Science.gov (United States)

    Douglas, Daniel; Attewell, Paul

    2014-01-01

    College graduation rates in the United States are low in both real and relative terms. This has left all stakeholders looking for novel solutions while perhaps ignoring extant but underused programs. This article examines the effect of "summer bridge" programs, which have students enroll in coursework prior to beginning their first full…

  3. Bridge to Success: Insight into Summer Bridge Program Students' College Transition

    Science.gov (United States)

    Walpole, MaryBeth; Simmerman, Herb; Mack, Cathy; Mills, John T.; Scales, Michael; Albano, Donna

    2008-01-01

    This study examines the college transition of students who participated in a summer bridge program. Three surveys collected longitudinal data on these students' aspirations and academic and social activities. Data provided from institutional research on their academic progress were also analyzed. A control group composed of non-participating…

  4. Vibration analysis of the Second Saikai Bridge—a concrete filled tubular (CFT) arch bridge

    Science.gov (United States)

    Yoshimura, Mistuhiro; Wu, Qingxiong; Takahashi, Kazuo; Nakamura, Shozo; Furukawa, Kazuyoshi

    2006-02-01

    Concrete-filled steel tubular (CFT) arch bridges have been rapidly developing in China since 1990. Research has focused on the static behavior, thermal stress and erection technique, however, and there has been very little research of natural vibrations and dynamic responses of these bridges. Japan's first CFT arch bridge in highway bridges, the Second Saikai Bridge, is now under construction in Nagasaki Prefecture. Furthermore, this bridge has a pedestrian bridge that is suspended under the girder, which is rare. Therefore, the natural vibration properties are examined, and the influence of pedestrian bridge structure on the natural vibration of main bridge is discussed first. Response analysis under a moving vehicle and pedestrian is carried out, and the response characteristics and response level are clarified. The natural vibrations and responses are compared to those of CFT arch bridges that have been constructed in China. Results show the fine performance of both main bridge and pedestrian bridge of the Second Saikai Bridge.

  5. 23 CFR 650.805 - Bridges not requiring a USCG permit.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Bridges not requiring a USCG permit. 650.805 Section 650... OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.805 Bridges not... permit is not required for bridge construction. This determination shall be made at an early stage...

  6. 33 CFR 118.110 - Daymarks and lateral lighting on bridges.

    Science.gov (United States)

    2010-07-01

    ... bridges. 118.110 Section 118.110 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.110 Daymarks and lateral lighting on bridges. (a... through bridges with U.S. aids to navigation system lateral marks and lights installed on...

  7. Building Better Bridges: An Evaluation of The Bridge to the Ph.D. Program

    Science.gov (United States)

    Ellyn Sanderson, Robyn; Lobel, Caroline; Agueros, Marcel A.; Anderson, Vanessa; Ash, Summer; Purdie-Vaughns, Valerie; Romero-Canyas, Rainer; Walker, Erica

    2016-01-01

    Columbia University's Bridge to the Ph.D. in the Natural Sciences Program is increasing the number of underrepresented scholars entering graduate programs and equipping them to succeed in these programs. In a given year, three to five Bridge participants are hired as full-time Columbia University research assistants for up to two years. Now in its seventh year, the Program supports seven participants, and its alumni (including five astronomers) have gone on to Ph.D. programs across the country. Although to date fewer than 40 people have participated in the Program, a number too small for an exclusively statistical evaluation of its effectiveness, we are collecting invaluable longitudinal data on the career progressions of underrepresented aspiring scientists across the natural sciences. At least a dozen Bridge alumni will earn their Ph.D. in the next two-three years, and we will then learn much more about the impact that the Bridge Program has had on our participants' trajectories. Among other things, we hope to use these data to determine the Program's effectiveness in developing feelings of self-efficacy and participants' confidence in their ability to succeed in doctoral programs, to measure the rate at which Bridge alumni successfully complete doctoral programs relative to their peers, and to identify the aspects of the Program that participants find most helpful to their progress at different stages of their paths to and through doctoral programs. Here we describe the data we have already obtained as part of our on-going study, and preliminary results from our analysis.

  8. FBG application in bridge health monitoring system of Wuhan Yangtze River 2nd Bridge

    Science.gov (United States)

    Liu, Jun

    2009-10-01

    For the traditional resistance strain sensor's shortage,for example,their stability,durability and monitoring scorpe could not satisfied the requirement of bridge monitoring system,put forward to adopt advanced fiber-optic bragg grating sensor and its technology to build up the bridge health monitoring system.Analysed the application scope and aim of difference kinds of fiber bragg grating sensors used, including stress strain sensors,temperature sensors,crack sensors and testing force ring sensors.According to the key construction sections as the project designed,expatiated their specific installation methods and construction craftwork in Wuhan Yangtze River 2th bridge.It formed distributed fiber sensing network of bridge with large-scale located fiber-optic bragg grating sensors, and pointed out the becareful prodeeding when to link no more than twenty sensors to one fiber for the demodulator precision.Discussed how to construct the data acquisition system and its function via the sensors and their demodulator.One fiber of the linked sensors connected to one channel of the demodulator and all together reached sixteen channels.The demodulator were connected to the switch through rj45 interface and communicated with the acquisition server.Designed the software program of data acquisition software system and the database,which used the Sqlite of the embed database to storage the configure information and receive the data through the TCP/IP protocol.It has been build a bridge health monitoring system base on fiber bragg grating technology.

  9. A review of bridge scour monitoring techniques

    Institute of Scientific and Technical Information of China (English)

    L.J. Prendergast; K. Gavin

    2014-01-01

    The high profile failure of the Malahide Viaduct in Dublin, Ireland, which is a part of the EU TEN-T network of critical transport links, was caused by foundation scour. Scour is a common soil-structure interaction problem. In light of current changes in climate, increasing frequency of flooding, coupled with the increasing magnitude of these flood events, will lead to a higher risk of bridge failure. Moni-toring scour is of paramount importance to ensure the continued safe operation of the aging bridge asset network. Most monitoring regimes are based on expensive underwater instrumentation that can often be subjected to damage during times of flooding, when scour risk is at its highest. This paper presents a critical review of existing scour monitoring equipments and methodologies with a particular focus on those using the dynamic response of the structure to indicate the existence and severity of the scour phenomenon affecting the structure. A sensitivity study on a recently developed monitoring method is also undertaken.

  10. Color in Bridge-Substituted Cyanines.

    Science.gov (United States)

    Olsen, Seth

    2016-12-29

    Theories of color in cyanine dyes have evolved around the idea of a "resonance" of structures with distinct bonding and charge localization. Understanding the emergence of resonance models from the underlying many-electron problem remains a central issue for these systems. Here, the issue is addressed using a maximum-entropy approach to valence-bond representations of state-averaged complete-active space self-consistent field models. The approach allows calculation of energies and couplings of high-energy valence-bond structures that mediate superexchange couplings and chemical bonding. A series of valence-bond Hamiltonians for a series of bridge-substituted derivatives of Michler's hydrol blue (a monomethine cyanine) is presented. The Hamiltonians are approximated with a simple linear model parametrized by the Brown-Okamoto σp(+) parameter of the bridge substituent. A quantitative lower bound on σp(+), beyond which a resonant cyanine-like ground state will not exist, is presented. The large effective coupling in two-state resonance models emerges from superexchange associated with either covalent bonding or charge-carrier delocalization, with the former contribution significantly the stronger. The results provide ab initio justification for empirical diabatic-state models of methine optical response. They are of general interest for understanding the optoelectronic response in cyanines.

  11. The iron abundance of the Magellanic Bridge

    CERN Document Server

    Dufton, P L; Thompson, H M A; Street, R A

    2008-01-01

    High-resolution HST ultra-violet spectra for five B-type stars in the Magellanic Bridge and in the Large and Small Magellanic Clouds have been analysed to estimate their iron abundances. Those for the Clouds are lower than estimates obtained from late-type stars or the optical lines in B-type stars by approximately 0.5 dex. This may be due to systematic errors possibly arising from non-LTE effects or from errors in the atomic data as similar low Fe abundances having previously been reported from the analysis of the ultra-violet spectra of Galactic early-type stars. The iron abundance estimates for all three Bridge targets appear to be significantly lower than those found for the SMC and LMC by approximately -0.5 dex and -0.8 dex respectively and these differential results should not be affected by any systematic errors present in the absolute abundance estimates. These differential iron abundance estimates are consistent with the underabundances for C, N, O, Mg and Si of approximately -1.1 dex relative to our...

  12. A review of bridge scour monitoring techniques

    Directory of Open Access Journals (Sweden)

    L.J. Prendergast

    2014-04-01

    Full Text Available The high profile failure of the Malahide Viaduct in Dublin, Ireland, which is a part of the EU TEN-T network of critical transport links, was caused by foundation scour. Scour is a common soil-structure interaction problem. In light of current changes in climate, increasing frequency of flooding, coupled with the increasing magnitude of these flood events, will lead to a higher risk of bridge failure. Monitoring scour is of paramount importance to ensure the continued safe operation of the aging bridge asset network. Most monitoring regimes are based on expensive underwater instrumentation that can often be subjected to damage during times of flooding, when scour risk is at its highest. This paper presents a critical review of existing scour monitoring equipments and methodologies with a particular focus on those using the dynamic response of the structure to indicate the existence and severity of the scour phenomenon affecting the structure. A sensitivity study on a recently developed monitoring method is also undertaken.

  13. Reinforcing of deposit slopes of Xiaowan Hydropower Station and application of prestressed anchorage cables%小湾水电站堆积体边坡支护与锚索技术应用

    Institute of Scientific and Technical Information of China (English)

    张德圣; 姜玉松; 吴诗勇

    2011-01-01

    With regard to the deposit slopes of Xiaowan Hydropower Station, the relevant reinforcing measures were analyzed, and the application of prestressed anchorage cables was highlighted. The results indicate that the slope reinforcements in the study area comprehensively adopt engineering protection and ecological protection techniques. The pre-stressing anchorage cables are the principal part of the engineering, and their drilling and grouting are the difficulty and keystone of the anchorage technology. The technology of concentric drilling and eccentric drilling with pipes can availably solve boring problem. By wrapping geotextile and thin canvas outside the prestressed steel strand, it can make concrete calculi protect steel strand of tensile section and reduce grouting quantity so as to avoid grouting waste.%分析小湾水电站堆积体边坡支护措施,研究预应力锚索技术的应用.分析认为,研究区边坡支护综合运用了工程护坡和生态护坡等边坡处理技术,预应力锚索是其主体工程,锚索孔钻孔和灌浆是该技术应用中的难点和重点,使用偏心跟管钻进技术和同心跟管钻进技术能有效解决钻孔难以成孔的问题;通过在锚索体外裹土工布和细帆布的方法,既保证了水泥结石对自由段锚索体的保护,又减少了浆量损耗,避免浆体浪费.

  14. Impact of bridge pier on the stability of ice jam

    Institute of Scientific and Technical Information of China (English)

    王军; 施发义; 陈胖胖

    2015-01-01

    River ice jam is one of the most important issues in rivers in cold regions during winter time. With the extra solid boundary due to the ice cover, the flow condition under ice-covered conditions is completely different from that of a open channel flow. The presence of bridge piers will further change the velocity field around the bridge piers. As a consequence, the formation and the accumulation of ice jams in the vicinity of the bridge pier will be affected. On the other side, the formation of an ice jam around the piers can cause extra turbulence to reduce the stability of a river bridge. The present study focuses on the stress analysis of the ice jam in the vicinity of a bridge pier. By developing a governing equation for describing the equilibrium state of an ice jam, the stability of the ice jam around bridge piers is analyzed and determined. As seen from the field data in literature, the stability estimations of an ice jam around bridge piers determined by the present method agree well with the field observations. Therefore, the proposed approach can be used for the prediction of the formation of ice jams around bridge piers.

  15. Probabilistic FE analysis of a cable stayed composite bridge

    NARCIS (Netherlands)

    Boer, A. de; Waarts, P.H.

    1999-01-01

    This paper describes the design of a new cable stayed composite bridge near Kampen in the Netherlands. In the design process, the safety of bridges is insured by means of partial safety factors for both strength and load parameters. As a result it is generally accepted that the structure as a whole

  16. Resolving Signals to Cohesion: Two Models of Bridging Inference.

    Science.gov (United States)

    Hegarty, Mary; Revlin, Russell

    1999-01-01

    Suggests two models of how readers create bridging inferences to resolve signals to textual cohesion. Evaluates reading times, verification accuracy, verification latency, and regressive eye fixations to support the model which views bridges as the result of a form of deduction in which the reader tacitly establishes premises that provide rational…

  17. Reliability assessment of welded steel details in bridges using inspection

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard; Yalamas, T.

    2014-01-01

    of the membrane stresses are estimated using a generic bridge structure and traffic measurements. The optimal reliability level for a welded detail in a bridge subjected to fatigue are estimated by cost benefit-analysis taking into account the risk of human lives through the Life Quality Index. Since the optimal...

  18. OnWien Bridge Oscillators as Modified Multi-vibrators

    DEFF Research Database (Denmark)

    Lindberg, Erik

    2014-01-01

    A tutorial introduction to electrical oscilla- tors. Investigating Wien bridge oscillators as modified multi-vibrators. Introducing chaotic behavior into a Wien bridge oscillator by means of adding a simple nonlinear cir- cuit as a load of one of the amplifier input terminals...

  19. Experimental Investigation of Aerodynamic Instability of Iced Bridge Cable Sections

    DEFF Research Database (Denmark)

    Koss, Holger; Lund, Mia Schou Møller

    2013-01-01

    of bridge cables under wind action. This paper describes the experimental simulation of ice accretion on a real bridge cable sheet HDPE tube segment (diameter 160mm) and its effect on the aerodynamic load. Furthermore, aerodynamic instability will be estimated with quasi-steady theory using the determined...

  20. Operational modal analysis of road-rail bridge

    Directory of Open Access Journals (Sweden)

    Cardoso M.

    2015-01-01

    Full Text Available In this paper, we describe an Operational Modal Analysis (OMA of the Bridge over the Tocantins River, a composite road-rail bridge located in the city of Marabá, state of Pará, northern Brazil. The bridge is part of the Carajás Railway, which is used by VALE Company to transport iron ore from “Serra dos Carajás”, the largest mineral reserve of the planet. The bridge has a length of 2310m, being the second longest road-rail bridge in Brazil. The study focused on the bridge central span (with 77 m of length and two adjacent spans (with 44 m of length. We employed Piezo-electric accelerometers to measure the dynamic response of the bridge under ambient excitation, which consisted of the passage of loaded and unloaded trains, road traffic, wind and river current. For modal identification, to avoid the influence of the train mass over the bridge system, we only considered acceleration signals of road traffic and signals corresponding to intervals after the passage of loaded trains, i.e., the study disregarded the intervals during which the trains were over the monitored spans. We obtained modal parameters through two identification methods: one in the time domain and other in the frequency domain. We also performed a comparative analysis between the experimental modal parameters, and the numerical results obtained with a finite element model provided by a third-part company.