bluuebunny/crossref_metadata_2025 huggingface dataset:
Refurbishment and lifetime assessment of the Beverentunnel in Liefkenshoek
Authors: Moyaert Joris , De Pauw Bart
Published: May 2013

The Liefkenshoek Railway Link is a new railway line for freight transportation in the port of Anwerp. Along with two new 6,1km long bored single-track tunnels the Beverentunnel, a 38 year old reinforced concrete tunnel crossing the Waasland dock on the left bank of the river Scheldt, was incorporated in the new railroad track. The 1200m long tunnel was built in open trench before the dock was excavated. A test program was set up to gather information and to deduct the remaining lifetime. As results were positive the tunnel will be taken into service after a structural refurbishment. Assessing a structure’s lifetime becomes even more important as DBFM-contracts arise frequently.
Development of Fire Resistant Shotcrete with Olivine Aggregates
Authors: Papayianni Ioanna , Papachristoforou Michail , Patsiou Vasiliki , Petrohilou Vasiliki
Published: May 2013

The objective of this research was the development of shotcrete mixtures with olivine aggregates that could act as protective coating in case of high temperature exposure, such as fire inside a tunnel.

Workability, unit weight, porosity, modulus of elasticity and compressive and flexural strength at the age of 7, 28 and 90 days of olivine-based concrete mixtures were tested and compared with reference mixtures with limestone aggregates and river sand. The residual mechanical properties of shotcrete mixtures were also measured after exposure to 400, 550, 750 and 850°C. Results showed that the replacement of limestone with olivine led to concrete superior in terms of strength at all temperatures of strain, indicating that the utilization of olivine-based shotcrete enables production of a fire resistant shotcrete at temperatures up to 850°C. The experimental procedure was completed with a successful pilot application of olivine-based shotcrete on concrete panels.
Determining the fire resistance of the Maastunnel with a mobile oven
Authors: schutte William , Ahammout Madiha , Blom C. B. M. (Kees) , Vermeer Martin
Published: May 2013

The Maastunnel in Rotterdam (the Netherlands) is the world’s oldest immersed concrete tunnel. Today’s increasing fire safety regulations require that both new and existing tunnels should reach high requirements on structural concrete integrity when exposed to extreme fire conditions.

A new mobile furnace has been used to execute in-situ tests with the ISO fire curve as well as the EC tunnel fire (RWS fire curve) on the existing Maastunnel in Rotterdam, the Netherlands.

This paper shows the use of the new furnace and the results of the EC tunnel fire and interpretations of the tests. Special attention is given to the effectiveness of the ancient structural fire protection with Chamotte tiles as a heat resistant layer. It will be shown that the mobile furnace gives important information about the concrete spalling behaviour in existing tunnels, which is crucial to prove for owners, engineers, authorities and advisors.
The Research on the Theory of Transverse Load Distribution of Continuous Beam Bridges
Authors: Jiang Zhemu , Wei Han , Chen Haibo , Gao Jundong , Li Chunzao , Zheng Kanglin
Published: May 2013

In China, the theory of transverse load distribution is widely used as a practical approximate method of calculation for space structure of girder bridges. This approximate method will lead to some error. So this article will take a five piece box girder continuous bridge as an example,A 3D solid finite element model of this bridge is used to calculate the transverse load distribution with the concentrated force applied on the main-span and side-span separately. The results are compared with bridge loading test data and show that: when calculating the transverse load distribution of the continuous bridge the corresponding equivalent deformation is more precise, while the moment is relatively unsatisfactory. And the side-span precise is more accurate than in the main-span, meanwhile using 3D solid finite element model to analysis the load transverse distribution is practical and accurate according to the comparison of FEM and experiment results.
Verification of three FEM programs in the analyses of a highway bridge
Authors: Teiter Zoltán , Szabó Bertalan , Jutila Aarne
Published: May 2013

The paper contains a verification of three FEM programs and different standards used in the design of a highway bridge in Hungary. The main span consists of a Langer-girder with 100 m span. The softwares used during the analysis are RM Bridge, LUSAS and Sofistik. These programs are suitable for the design of major bridges.
Recommendations for assessing and upgrading old urban quay walls
Authors: Roubos Alfred , de Gijt Jarit
Published: May 2013

From the earliest days, quay walls have played an essential role in the shipment of goods in the Netherlands. Therefore the relative old cities have historic quay wall structures. During the life time of these quay walls, the structures have been exposed to various loads due to changing boundary conditions. Currently there is no specific guideline for determining the minimal required safety of these old and historic structures. A specific point of interest is describing the methods and the extension of an inspection in urban areas.

Therefore an expert group is preparing a guideline for upgrading and analysing old quay walls in urban areas. This guideline is called “CUR recommendation C186”, In this CUR recommendation a design philosophy and practical guidelines for inspection protocols and verification are presented. The verification of the remaining life time in relation to the latest developments will be in line with the standardisation of the new Euro codes and national appendixes. Nowadays many urban quay walls are used for other purposes compared to their originally functional requirements. The quay walls have to withstand loads due to traffic and trees and have often a monumental functions. The quay walls are a part of the urban landscape in the city centres. Adaptation is necessary and commonly the execution of these adaptations will take place in highly populated areas. For these complex situations, adaptations and execution (near trees for example), practical recommendations are described.
CRIAM: Structural Risk Index Weighing Model
Authors: de Boer Ane , Booij Nico , Copier Paul
Published: May 2013

In the Netherlands, the partnership between the Ministry of Infrastructure and the Environment and the market has led to the new method CRIAM, which stands for ‘Structural Risk Index Weighing Model’. With this model, an inspector and engineer can objectively determine whether a Unity Check, further material research or a complete re-examination is necessary. Many hours of research and calculations of infrastructural objects were saved with this objective weighing model. This process has led to considerable savings in both time and social costs. In addition, this method objectively determines a score which provides the urgency in which further research or re- examination is required. Meanwhile over 800 objects have been classified by urgency in The Netherlands. The uniform objective CRIAM score was successfully validated by the Ministry of Infrastructure and the Environment using historical figures and refined re-examination of objects, which took already place in the past.
Structural Response due to Violent Wave Impacts on a Vertical Structure with a Cantilevering Slab
Authors: Kisacik Dogan , De Backer Hans , Van Bogaert Philippe
Published: May 2013

The Pier of Blankenberge, located along the Belgian coast is a structure consisting of a vertical core attached to an overhanging horizontal slab, which is exposed to violent wave impacts on the vertical and horizontal parts. This introduces an important uplifting force. The lift forces consist of impact loads of high magnitude and short duration. As opposed to purely vertical or horizontal surface type structures, structures consisting of both vertical parapets and horizontal cantilever slabs have rarely been considered. The behaviour of cantilever structures above sea level is similar to bridge conduct, since the incident loads vary with time and space. The effect of wave impact on the lower side and the vertical parts of a cantilever structure above sea level, results in local patch loading on a swaying system, introducing local deformations, stresses and accelerations, whose peak values are not necessarily relevant for the entire structural behaviour. This patch loading, moving rapidly with time, as an upward pressure front, acting on the lower side of the cantilevering platforms may cause local deformations, but does not necessarily cause collapse or endanger neither structural equilibrium nor stability. The pressure wave is a frontally moving load, limited in time and space, its sign instantaneously being reversed immediately nearby the maximum wave amplitude. Fundamental insight in the structural response of cantilever structures above sea, subjected to wave impact, is being developed in the research for this manuscript. The main objective of this article is the study of the structural response of the monolithic overhanging structure. The focus is on the structural response of the structure. This is analysed by numerical modelling of the structural response based on recently proposed design values for such wave loading.
Analysis of Traffic Effects on a Dutch Highway Bridge
Authors: Miao Shengfa , Knobbe Arno , Koenders Eddy , Bosma Carlos
Published: May 2013

In this paper, we propose a method for reliably extracting modal parameters from concrete bridges, which depends on the proper identification of vehicles passing the bridge. We collect data from a sensor network installed on a large highway bridge in the Netherlands, called the Hollandse Brug. There are three sensor types involved in the network, sensing strain, vibration and temperature. Large traffic events, such as trucks crossing the bridge, can be recognized clearly in the strain signal, so we use it to identify the exact moments of vehicles passing. At the same time, the measured strain is also influenced by other factors, such as traffic jams and temperature changes. We remove these factors, which interfere with the proper identification of traffic events, with an improved threshold-based classification method, and obtain a number of peaks with the zero-crossing and local maximum method. We then divide these peaks into different categories with a supervised classification method. The signals produced by the vibration sensors when excited by passing trucks is a good source for analysing structural parameters of the bridge, so we extract the free vibration periods of the vibration signals associated with truck events in the strain signals, and subsequently conduct modal analysis.
Monitoring during Refurbishment of Port Infrastructure
Authors: De Backer Hans , Outtier Amelie , Schotte Ken , Stael Dries , Nagy Wim , Van Bogaert Philippe
Published: May 2013

Monitoring of structural parameters during construction can be an important aid for execution. Especially when studying the long-term behaviour of structures, e.g. build-up of ground pressures or fatigue effects, it can become necessary to resort to monitoring. This research paper discusses two such projects.

A first project deals with the refurbishment of a lock door of the Port of Zeebrugge, Belgium. In order to allow for refurbishment, the ground water level in the door chamber had to be lowered considerably, resulting in a variation of the ground pressure on the concrete walls of the lock chamber. As a safety measure large steel struts were added, going through the lock door. Since much uncertainty existed concerning the size of the ground pressure variation, a monitoring system was installed to measure the normal forces in the struts and alarm levels were defined. Initial results pointed out that temperature variation in the longitudinally constrained struts took up a considerable part of the capacity of the struts.

A second project is concerned with the refurbishment of part of the counterweight structure of one of the bascule bridges crossing the Van Cauwelaertsluis, which is one of the most important locks allowing entrance to the Port of Antwerp, Belgium. Because of uncertainty about the size of the stress cycles in the movable part during bridge operation, a number of strain gauges are installed during renovation before any of the axles connecting the bridge to the bascule system are installed. Afterwards, stress build up will be monitored during the remaining construction phases, as well as during test operation of the bridge to verify design assumptions. Monitoring will continue afterwards during the first few months of operation.

This article gives an overview of these experiences and on the lessons learned concerning power supply, possible electromagnetic interference and structural consequences
Energy Harvesting for Sensors in Infrastructure Monitoring and Maintenance
Authors: Han Bo , Kalis Antonis , Papadias Constantionos , Soman Rohan , Kyriakides Marios , Onoufriou Toula , Nielsen Rasmus , Prasad Ramjee
Published: May 2013

Infrastructure monitoring and maintenance needs various kinds of sensors; all these sensors are expected to have long lifetime and self- maintenance and not be replaced. For non-destructive infrastructure monitoring, these sensors should be wireless, however, wireless sensors have an inherent problem on energy efficiency and energy consumption. Thus, how to power sensors efficiently or how to design a self-powered sensor is a key issue to this problem. Energy harvesting technique emerges as a new direction on getting power from environment. Piezoelectric and electromagnetic harvesting methods on vibration are analysed in this paper, and a low cost

self-powered conversion circuit is modelled and simulated. Other kinds of energy harvesting are also briefly compared with those two methods; the solar-electric, vibration-electric, thermal-electric and electromagnetic-electric energy harvesting methods are briefly compared in this paper.
Structural Health Monitoring of the Hammersmith Flyover
Authors: Webb Graham , Middleton Campbell
Published: May 2013

A variety of monitoring equipment has been installed on the Hammersmith Flyover in London in an attempt to provide more information about the state of deterioration of this key piece of infrastructure. This paper presents an analysis of some of the data obtained, to determine whether useful conclusions about the structural condition of the bridge can be drawn and to evaluate the effectiveness of these monitoring systems.

While some useful conclusions about the condition of the bridge can be drawn, there is much data which is of very limited use. Theoretical predictions can be used to demonstrate why some sensors will not provide useful information. Lessons learnt from this project can be applied to the design of future monitoring systems to prevent the installation of unnecessary sensors.
Damage Identification on an Iron Bridge Based on Spectral Analysis
Authors: Tributsch Alexander , Adam Christoph , Billmaier Maximilian
Published: May 2013

This paper reports about damage identification on a single-span iron bridge based on recorded ambient vibrations. Several local damage scenarios were imposed stepwise to the structure.

Random vibration tests were conducted, and the induced dynamic response of the bridge in the undisturbed as well as in modified “damaged” conditions was recorded. The recorded vibrations were subjected to Operational Modal Analysis identification methods and to spectral analyses. It is shown that the shift of the relative cumulative spectral energy at different damage levels is an appropriate damage indicator. Thus, spectral analysis could be a promising tool for long-term vibration based structural health monitoring.
Experimental Validation of the Acoustic Emission (AE) Method for the Cracking Process Determination and Location in Concrete Elements
Authors: Goszczyńska Barbara , Świt Grzegorz , Trampczyńsf Wiesław , Krampikowska Aleksandra , Tworzewska Justyna , Tworzewski Pawel
Published: May 2013

Verification of the acoustic emission method (AE), by the identification and analysis of active damage processes (IADP), is presented in the paper. Signals database was determined for individual processes appearing in reinforced concrete in specially planned laboratory tests.

Comparing AE signals, generated within structures under service load, with previously created database, one can identify the processes of active damage occurring in an element. They can be located on the basis of the difference in the time, that AE signal reaches the sensors with known wave velocity.

Experiments were carried out on concrete beams subjected to continuous loading, up to failure load. It was found that using the IADP method, it was possible to detect and locate creation of cracks. It was even possible to recognise creation of shear cracks and bending cracks.
Mechanical behaviour and failure mechanism of perfobond shear connectors in steel-concrete hybrid structure
Authors: Wei Xing , Xiao Lin
Published: May 2013

Load carrying capacity of perfobond shear connectors in steel-concrete hybrid structure are focused on in this paper. Mechanical behaviour of a perfobond shear connector is influenced by various parameters in steel-concrete structure. To evaluate the behaviour of perfobond shear connectors, push-out tests were carried out. In the experimental program, 24 push-out tests of connectors with 20 mm thickness and with 8 mm thickness, both in different opening and with different transverse reinforcement were accomplished. Based on the load-slip relation of connectors, connection behaviour was analysed and failure mechanism was identified and the load capacity, maximum slip and shear stiffness were quantified. The results of these tests have shown that failure mode of perfobond shear connector changes with different thickness of the perforate plate. Including shear failure of perforate plate, flexural and shear failure of transverse rebar and shear failure of the transverse rebar, three main failure modes of shear connector may occur.
Design of Computer Models for Describing the Dynamic Behaviour of the Ballast Substructure of Railway Bridges
Authors: Fink Josef , Kirchhofer Johannes , Hackl Klaus
Published: May 2013

In this paper the most actual research results of investigating the dynamic behaviour of the ballast substructure of railway bridges are shown. Especially the stiffness and damping properties of the ballast will be discussed. The intention of these investigations is to create a computer model with determined parameters, describing the behaviour of railway bridges in order to make possible detailed, fast and efficient dynamic calculation for this type of bridges.
Strength characteristics for the structural assessment of existing concrete structures
Authors: Vervuurt Adri , Courage Wim , Steenbergen Raphaël
Published: May 2013

For the assessment of the in situ compressive strength in structures and precast concrete components EN 13791 applies. Among others, this standard may be adopted when doubt arises about the compressive strength in the structure. However, for assessing the structural safety of existing structures of many years of age, the method given in EN 13791 seems not to be applicable and may lead to an unsafe approach for determining fck,cube.

In this paper a method is presented for determining the characteristic concrete strength obtained from in situ cored cylinders. The method is based on EN 1990 (Eurocode Basis of Design) and has been validated by experimental results of almost 200 existing concrete structures in the high way road network in The Netherlands. From the results of these tests it is confirmed that the method given in EN 13791 overestimates fck,cube, but still a substantially higher strength may be expected for existing concrete structures compared to the design strength.

Moreover, the results of the material tests on cored cylinders have been adopted for estimating a reliable strength value for comparable structures but for which no core drilling test results are available. Taking into account uncertainties, this results in lower estimates for fck,cube for such structures. Nevertheless, it may be assumed that the strength for determining the structural safety is higher than adopter in the original design.
Calibration of partial safety factors for the assessment of existing bridges
Authors: Crémona Christian , Poulin Benoît , Colas Anne-Sophie , Michel Jérôme , Marcotte Clarie , Vion Bruno , Orcesi Andre , Sadone Raphaelle
Published: May 2013

The design codes use safety margins which, in general, exceed those that are reasonable to accept for the assessment of existing bridges. Knowledge about a structure can be improved by further investigations and this can justify modifying partial safety factors. In this context, the Technical Centre for Bridge Engineering (CTOA) of the Technical Department for Roads, Road Safety and Bridges (SETRA) has initiated in 2009 a large study for the calibration of partial factors adapted to the assessment of existing bridges. Based on the reliability theory, its objective is to provide modified partial factors based on tabulated experimental in-situ results. The study is performed on different families of standard bridges but the present paper will only highlight the preliminary results obtained for reinforced concrete slab bridges.
Large-scale Testing of Retro-reinforced Brick Arches
Authors: Garrity Stephen
Published: May 2013

Vertical static load tests on sixteen 2,95m span multi-ring clay brick arches were carried out to investigate the effectiveness of retro-fitted steel reinforcement as a strengthening measure. The principal parameters investigated were the arch geometry; arch ring thickness; area and distribution of reinforcement; type of inter-ring shear reinforcement and mortar strength. In each case a full width line load was applied incrementally to the upper surface of the arch at quarter span until collapse occurred. In all cases, longitudinal reinforcement was found to delay the onset of cracking and to increase the load carrying capacity. Radial dowels were found to be the most effective means of preventing ring separation and the simplest and quickest to install. Longitudinal reinforcement was found to be the most effective when used with measures to prevent ring separation.
Rescuing the Sidi Rached Bridge
Authors: Petrangeli Marco , Pietrantoni Massimo
Published: May 2013

The Sidi Rached Bridge, built in the early 20th century, crosses the deep Rhumel canyon in the centre of Constantine, Algeria. The bridge is made of 27 arches, with spans varying from 12 to the 68 metre of the main arch crossing the Rhumel 102 metres above the riverbed. The bridge is a famous city landmark and one of the main cultural heritage of Algeria as well as the largest masonry structure of this type in Africa. The 8 spans on the right bank have been suffering for over 50 years, from intermitting slope instability. The problem has been addressed and temporarily solved few times now. All the attempts tried to anchors the pier foundations to the bedrock while reducing the cause of soil instability with drainages. During the ’70, the downhill displacement of the abutment spiked and the structure had to be disconnected severing the first arcade and replacing it with a simply supported buffer steel girder. After 30 years of relative calm, the landslide peaked again in 2008 causing severe damage to al the piers on the right bank and the near collapse of one arch. A new campaign of assessment, reconstruction and strengthening has therefore been undertaken. Using high precision topographic readings and 3D finite element model of the bridge the mechanics of what is taking place in the structure has been fully understood. Certainly more difficult will be the attempt to prevent the slope and pier foundations to keep on sliding. The paper presents the results of the study and the first interventions taken while monitoring, studies and works proceed on this historical monument that still provides a vital crossing in the hearth to one of the most populous cities of North Africa.
Historical and Modern Structures at the Railway Stations
Authors: Kido Ewa Maria
Published: May 2013

Since 1980s, railway architecture has been experiencing “station renaissance”. Along with this trend, many large historical stations have been refurbished, upgraded and developed. Modern extensions need to fit to historical settings and to add additional values of modernity and attractiveness to railway stations. This paper examines such stations on the example of Europe and Japan and concludes that these transport facilities with their re-born buildings improving travel by rail, are

new-generation station and often urban landmarks.
Constantine Viaduct, Algeria
Authors: Hansen Torben Scholdan
Published: May 2013

The Constantine Viaduct is a major road and bridge project in Constantine, Algeria. The project will improve the infrastructure significantly when completed in 2014. During the design, special attention has been given to road traffic solutions, pedestrian access and aesthetical aspects due to the urban location. The main design challenges associated with placing a major road and bridge in the middle of an old city with many restrictions have been defining the alignment, complex geometry of bridge structures and need for extraordinaire geotechnical structures. The new viaduct bridge will be a significant cable-stayed bridge on the African continent. It will stand out as a very elegant cable-stayed bridge with its slender appearance, clear lines and prominent location next to the other famous and beautiful bridges in Constantine.
Renovation and repair of a masonry arch bridge in Thumaide, Belgium
Authors: van Roosbroeck Thijs , Dister Vincent , Ney Laurent
Published: May 2013

A new windmill park is to be built in the centre of the Hainaut province in Belgium. During construction heavy transport will need to pass over a 20m span masonry arch bridge built at the beginning of the twentieth century. Currently, the spandrel walls have deformed significantly due to the pressure of the backfill. The spandrel walls and the arch show cracks and locally bricks are missing. The bridge, that crosses the RaVel (a network for cycling in the Walloon region), therefore needed a well-considered renovation to guarantee the safety of cyclists passing under the bridge. Also verification was required for the exceptional transport during construction of the wind mill park. This paper will discuss in detail how the different analysis models and strategies complemented each other, and helped convince the client to restore rather than demolish this masonry arch bridge.
Synthesis of sources with Markovian features
Authors: Martínez-Niconoff G. , Martínez-Vara P. , Andrés-Zarate E. , Silva-Barranco J. , Munoz-Lopez J.
Published: May 2013

We realize the design and synthesis of partially coherent secondary sources illuminating an ensemble of mobile transmittances in a tandem array. The motion states of the transmittances are random variables which are synchronized by means of the conditional probability density function whose control allows generating sources whose light emission corresponds with a Markov chain. The experimental results are shown.
Influence of interfaces reflectivity for central thickness measurement of a contact lens by low coherence interferometry
Authors: Verrier I. , Veillas C. , Lépine T.
Published: May 2013

This paper evaluates quantitatively the relative interfaces reflectivity of a soft contact lens set in air or in water by a low coherence interferometric method. The sensitivity of the set-up is then measured and the minimum reflectivity is estimated to be as low as 0.02%. Measurement of the central thickness of the lens, even when it is immersed in water, is then possible using a new supercontinuum source.
Holographic superresolution using spatial light modulator
Authors: Hussain A. , Martínez J. L. , Campos J.
Published: May 2013

This paper describes a technique of superresolution using a reflective mode spatial light modulator, a coherent source of light, and a transmission mode object placed in the input plane of an imaging system, in particular we are using for the demonstration a 4f system. The spatial light modulator (SLM) enables for creating tilted plane wave illumination and it also permits adding constant phases of 0, π/2, 3π/2 and π. The angle of illumination created by the SLM is defined according to the dimension of aperture placed at the Fourier plane of 4f optical system. For each defined angle of illumination created by the SLM four holograms corresponding to the transmission mode object are recorded. This system is capable of retrieving phase and amplitude information of the images, corresponding to each impinging illumination. By simply adding these complex images a super resolved image is obtained.
Refractive index determination of SiO2 layer in the UV/Vis/NIR range: spectrophotometric reverse engineering on single and bi-layer designs
Authors: Gao L. , Lemarchand F. , Lequime M.
Published: May 2013

In this paper we use spectrophotometric measurements and a Clustering Global Optimization procedure to determine the complex refractive index of SiO2 layer from 250 nm to 1250 nm. A special commercial optical module allows the reflection and transmission measurements to be made under exactly the same illumination and measurement conditions. We compare the index determination results obtained from two different single layer SiO2 samples, with high and low index glass substrates, respectively. We then determine the refractive index of SiO2 for a bi-layer design in which the first deposited layer is Ta2O5. The corresponding solutions are discussed and we show that the real part of the complex refractive index obtained for a bi-layer is slightly different to that found for a single layer investigation. When SiO2 is included inside a thin film stack, we propose the use of an index determination method in which a bi-layer is used for the real part of the complex refractive index, and single layer determination is used for the imaginary part of the refractive index in the UV range.
Dual wavelength continuous wave laser using a birefringent filter
Authors: Treviño-Palacios C. G. , Zapata-Nava O. J. , Mejía-Uriarte E. V. , Qureshi N. , Paz-Martínez G. , Kolokolstev O.
Published: May 2013

We report simultaneous dual wavelength continuous laser emission with minimum cavity elements. Tunable dual wavelength emission between 805 nm and 840 nm was observed with controlled peak separation around two nanometers, which corresponds to approximately one terahertz. Dual wavelength laser operation is possible using a novel intracavity two plate birefringent filtering element.
Reducing BER of spectral-amplitude coding optical code-division multiple-access systems by single photodiode detection technique
Authors: Al-Khafaji H. M. R. , Aljunid S. A. , Amphawan A. , Fadhil H. A. , Safar A. M.
Published: May 2013

In this paper, we present a single photodiode detection (SPD) technique for spectral-amplitude coding optical code-division multiple-access (SAC-OCDMA) systems. The proposed technique eliminates both phase-induced intensity noise (PIIN) and multiple-access interference (MAI) in the optical domain. Analytical results show that for 35 simultaneous users transmitting at data rate of 622 Mbps, the bit-error rate (BER) = 1.4×10−28 for SPD technique is much better compared to 9.3×10−6 and 9.6×10−3 for the modified-AND as well as the AND detection techniques, respectively. Moreover, we verified the improved performance afforded by the proposed technique using data transmission simulations.
Theoretical demonstration of highly efficient cw THz generation by using composite photonic-structure elements
Authors: Oyamada A. , Kitaguchi H. , Ebata K. , Ishihara H.
Published: May 2013

We theoretically propose one-dimensional composite photonic structures for high-resolution THz spectroanalysis. We compare the performance of two GaAs/AlAs composite photonic-structure devices, one with usual 1/4-wavelength layers of distributed Bragg reflectors (DBRs), and the other with the designed DBRs. The device with designed DBRs shows the optical-to-terahertz conversion efficiency up to 10−5 and wide frequency tunability ranging from sub-THz to 3 THz. We found that the composite photonic structure allows us to control photonic modes with a high degree of freedom by flexible structure designs. This device achieve a cw THz source with a highly narrow bandwidth operating at room temperature.
Analysis of hybrid dielectric-plasmonic slot waveguide structures with 3D Fourier Modal Methods
Authors: Čtyroký J. , Kwiecien P. , Richter I.
Published: May 2013

Recently, plasmonic waveguides have been intensively studied as promising basic building blocks for the construction of extremely compact photonic devices with subwavelength characteristic dimensions. A number of different types of plasmonic waveguide structures have been recently proposed, theoretically analyzed, and their properties experimentally verified. The fundamental trade-off in the design of plasmonic waveguides for potential application in information technologies lies in the contradiction between their mode field confinement and propagation loss: the higher confinement, the higher loss, and vice versa. Various definitions of figures of merit of plasmonic waveguides have been also introduced for the characterization of their properties with a single quantity. In this contribution, we theoretically analyze one specific type of a plasmonic waveguide – the hybrid dielectric-loaded plasmonic waveguide, or – as we call it in this paper – the hybrid dielectric-plasmonic slot waveguide, which exhibits very strong field confinement combined with acceptable losses allowing their application in some integrated plasmonic devices. In contrast to the structures analyzed previously, our structure makes use of a single low-index dielectric only. We first define the effective area of this waveguide type, and using waveguide parameters close to the optimum we analyze several waveguide devices as directional couplers, multimode interference couplers (MMI), and the Mach-Zehnder interferometer based on the MMI couplers. For the full-vector 3D analysis of these structures, we use modelling tools developed in-house on the basis of the Fourier Modal Method (FMM). Our results thus serve to a dual purpose: they confirm that (i) these structures represent promising building blocks of plasmonic devices, and (ii) our FMM codes are capable of efficient 3D vector modelling of plasmonic waveguide devices.
Role of the Nutrition Professional: In High-risk Obstetrics Inpatient Teams
Authors: Gurau Julia , Cronk Aleris , Pelliccia Maria , Vandenbussche Katherine
Published: May 2013

Beyond the management of gestational diabetes and weight control, limited literature exists on nutritional management in high-risk pregnancies. This study is a starting point for understanding the role of the registered dietitian (RD) in high-risk obstetrics (HRO) inpatient teams. Demographic information was gathered on Ontario HRO inpatient units and patient characteristics, and the RD’s role in this setting was explored. Representatives from all six HRO units in Ontario completed a questionnaire. Five of the HRO units had an RD on the team. The RDs stated that their primary role in the unit involved providing nutrition education and support, screening patients for nutritional risk, and writing vitamin and mineral orders. This was the first study in which RDs’ role in HRO inpatient units was examined. Existing literature supports the role of good nutrition in preventing and treating the conditions seen in HRO units; however, RDs’ specific role remains unclear. Future studies are needed to analyze the effect of nutrition on these HRO conditions, and to support the development of best practice guidelines.
Sarkozy and Merkel: The Undeniable Relevance of the Franco-German Bilateral Relationship in Europe
Authors: Vassallo Francesca
Published: May 2013

In 2013 France and Germany will celebrate the fiftieth anniversary of the Élysée Treaty, signed by the two countries to create a close collaboration in the interest of peace and prosperity. Over the course of five decades, different couples of French Presidents and German Chancellors have dealt with the Paris-Berlin relationship in slightly different ways, some with more success than others. Despite the many changes in the European context and to the balance in the alliance between France and Germany, the initial motivation and meaning of the treaty remains astonishingly valid today, especially in light of its positive contribution to European integration. Even with many possible factors weakening the two countries' core relations, the Franco-German duo retains its historically dominant influence in successful European governance, as the recent Merkozy situation showed.
Bringing social cohesion into the equation of regional integration: The case of Southern Africa
Authors: Noyoo Ndangwa
Published: May 2013

Social cohesion is a powerful force that has helped to change and reshape
the political landscape of southern Africa in the last four decades. However,
social cohesion is rarely factored into regional integration endeavors
in this part of Africa, which are in the main, geared towards economic
imperatives. With economic development as the primary objective of nations
in the Southern African Development Community (SADC), the assumption
here seems to centre on the notion that once the region has been
economically integrated, then human development would follow. This
thinking is in line with the neo-liberal paradigm of “trickle down” economics
which has not been very helpful to states of this region. Nonetheless,
this lop-sided view of regional integration has a history.
Release of Contractures by Subcutaneous Pedicled Rhomboid Flaps
Authors: Mannan II , Khundkar SH , Ahmed T , Ibrahim FB
Published: May 2013

The subcutaneous pedicled rhomboid flap is a technique that can release scar contractures without skin graft or additional flap. This study was planned to evaluate the efficacy of this technique. This prospective interventional study was conducted in the department of Plastic Surgery, Dhaka Medical College Hospital, over a period of 16 months. A total of 28 procedures of subcutaneous pedicled rhomboid flap were performed on 12 patients. The contractures were released successfully by the rhomboid flaps. The mean percentage gain in length of the scar band was 77.28%. Most of the cases had complication free recovery. The clinical results indicated that the subcutaneous pedicled rhomboid flap is an effective and versatile technique for releasing scar contractures in different parts of the body. DOI: http://dx.doi.org/10.3329/bdjps.v3i1.14998 Bangladesh Journal of Plastic Surgery 2012, 3(1): 3-6
Ultrasound Assessment of Amniotic Fluid in Predicting Adverse Outcome in Prolonged Pregnancy
Authors: Sultana P , Anwary SA , Ahmed ZU , Alfazzaman M , Kulsum U
Published: May 2013

DoIDOI: http://dx.doi.org/10.3329/medtoday.v24i2.15006 Medicine Today 2012 Vol.24(2): 55-58
Tuberculosis of Spine Magnetic Resonance Imaging (MRI) Evaluation of 42 Cases
Authors: Khalequzzaman SI , Hoque HW
Published: May 2013

Tuberculosis of spine is common for Bangladesh. Imaging modality is importent for diagnosis of it.Forty-Six clinically suspected tubeculous spondylitis patient were included in this prospective, consecutive study during July 2003 to June 2005. Among them, 42 cases of MRI and histology proven were included in the article. The peak incidence was found to be in 3rd decade (43.48%) with male predominance, 2.5 times more than female. The mean age was revealed 33.3 years. Highest occurrence was in double vertebrae involvement (42.86%) along with continuous vertebral involvement (85.71%). Destruction & collapse found in most case (88.10%) with predominance with posterior element involved (54.76%). Spinal deformity was least (11.90%). Para-spinal soft tissue involvement was found in most cases ((80.95%) with no calcification. 21.43% shows cord compression. MRI was found sensitive and accurate modality for diagnosis of TB spondylitis.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15007 Medicine Today 2012 Vol.24(2): 59-62
Compression Method in the Complex Treatment of Bleeding Haemorrhoids
Authors: Alfazzaman M , Anwary SA , Rahman MM , Islam MR
Published: May 2013

DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15008 Medicine Today 2012 Vol.24(2): 63-65
Age Related Changes of Human Uterus-A Postmortem Study
Authors: Uddin MS , Al-Muhaimin M , Begum N , Sultana Z
Published: May 2013

The uterus is an essential principal accessory female reproductive organ whose function is to receiving and rearing an egg within its mucosa, nourishes and protects the embryo, and expels it at the proper time. Uterus related clinical conditions such as leiomyomas also known as myomas or fibroid and carcinoma cervix are major medical conditions within aging population. Detailed morphological knowledge is essential for proper diagnosis and management of uterine diseases. Study design was descriptive type of study. Place and period of study was department of anatomy, Sylhet M A G Osmani Medical College, Sylhet, from July 2006 to June 2007. Present study was performed on 50 autopsied human uterus of age ranging from 1 to 65 years. The samples were collected from unclaimed dead bodies that were autopsied in the morgue of Department of Forensic Medicine of Sylhet M A G Osmani Medical College, Sylhet. The samples were divided into four age groups. Group A (1-12 years), Group B (13-24 years), Group C (25-46 years) and Group D (46-65 years). All samples were studied morphologically. Statistically significant positive correlation was found between age breadth and thickness of uterus. There were changes in the morphology of uterus in relation to age.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15010 Medicine Today 2012 Vol.24(2): 70-72
Aetiological Study of Neonatal Hyperbilirubinaemia-A Hospital Based Prospective Study
Authors: Mallick PK , Alam B
Published: May 2013

A prospective Hospital based study was done to find out the aetiology of neonatal hyperbilirubinaemia. One hundred cases were studied during a period from January to December 2003 on the neonatal unit of CMCH and different clinics of chittagong city. Among them 69% were male and 31% were female. Neonatal septicemia was the commonest cause of neonatal hyperbilirubinaemia found in 28% case follwed by blood group incompatibility (27%).DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15011 Medicine Today 2012 Vol.24(2): 73-74
Montelukast in Allergic Rhinitis: A Review
Authors: Chowdhury MAN , Uddin MS , Das S , Hoque M
Published: May 2013

Leukotriene inhibitors are the first new class of medications for the treatment of persistent asthma that have been approved by the U.S food and drug Administration in more than two decades. They also have been approved for the treatment of Allergic Rhinitis. Leukotrienes are inflammatory mediators that are known as the slow-reacting substance of anaphylaxis. Synthesis of these mediators results from the cleavage of arachidonic acid in cell membranes, exert their biologic effect by binding and activating specific adaptors. This occurs in a series of events that lead to their important role in the Allergic Rhinitis. Because agents lead to the production of symptoms, the use of leukotriene inhibitors, particularly montelukast seems appropriate. These classes of drug can block the binding of leukotrienes to CysLT1 receptors and can also result in the prevention of leukotriene activity. Montelukast is the most commonly used inhibitor of the leukotriene pathway because of its ease of use , good safety profile, and once-daily regimen. We conduct a systematic review of studies that have evaluated montelikast in the treatment of Allergic Rhinitis. This review focuses on the pathophysiology and effect of montelukast in Allergic Rhinitis. The purpose of this paper is to provide an overview of the accumulation data concerning these agents in treating Allergic Rhinitis. Montelukast provides an effective and well tolerated oral treatment for Allergic Rhinitis.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15012 Medicine Today 2012 Vol.24(2): 75-78
A Case Report of Takayasus Arteritis
Authors: Khan MAM , Banoo H
Published: May 2013

Takayasus arteritis, or pulseless disease is a rare, idiopathic, chronic granulomatous vasculitis that affects aorta and its major branches. This report describes a 57- year-old man who presented with gradual loss of vision, syncopal attack and arm claudication. His ocular findings suggested bilateral ocular ischemic syndrome. He was later diagnosed as having Takayasus disease.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15013 Medicine Today 2012 Vol.24(2): 79-81
A Case Study of Drug Abuse
Authors: Islam RN , Tabessum NE , Safiuzzaman AKM , Sarker MMI
Published: May 2013

There has been increasing the incidence of addiction to certain drugs amongst people belonging to various strata of society particularly amongst young people in our country as well as western countries. Our patient is a 24 year old male with a history of phensidyl addiction for 4.5 years. Without having it he cant do anything. If he cannot take it, peevish temperament occurs and he doesnt wish to work or even talk. He collects drugs from the local spots or a particular person. This condition is very much dangerous both to the individual and socio-economic condition of a country. Drugs addiction is a condition of periodic or chronic intoxication produced by the repeated consumption of a drug or drugs by and individual effect of which is detrimental to the individual or to the society. A more intensive research, action program, and social movement are needed. It is also needed to strengthen family and social values and religious ethics in order to maintain a stable and drug-free society.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15014 Medicine Today 2012 Vol.24(2): 82-84
Lupus Pernio-A Rare Case Report
Authors: Uddin MJ , Huda MS , Rahaman MM , Siddique MRU , Islam MA
Published: May 2013

Lupus Pernio is a chronic form of Sarcoidosis and it is a poor prognostic factor. It is commonly associated with bone cyst and pulmonary fibrosis. Spontaneous remission is rare. On this occasion we are reporting a case of 25 year old lady presented with a well defined erythematous plaque on the tip of the nose for last 8 years without any associated findings.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15016 Medicine Today 2012 Vol.24(2): 87-88
Leiomyoma of Vagina- A Case Report
Authors: Sultana N , Ara F , Akhtar A , Haque F
Published: May 2013

A 35 years old lady came from Borobari, Gazipur was admitted in the gynae. department of TMMC Hospital with mass in the vagina for 9 months, irregular per vaginal bleeding and dyspareunia for 1 month. Examination revealed an irregular solid mass arising from the posterior vaginal wall, which was ulcerated superficially. After conservative treatment, excision biopsy was taken and histopathology report revealed leiomyoma of the vagina. The case was managed surgically alone.DOI: http://dx.doi.org/10.3329/medtoday.v24i2.15017 Medicine Today 2012 Vol.24(2): 89-90