1 

Level III Reliability methods feasible for complex structures
The paper describes the comparison between three types of reliability methods: code type level I used by a designer, full level I and a level III method. Two cases that are typical for civil engineering practise, a cablestayed subjected to traffic load and the installation of a soil retaining sheet pile wall, have been analysed with the three reliability methods and conclusions are drawn with respect to accuracy and computational effort. As expected the level III method uses more computational effort than a code type level I method. It is however shown that in practise, the effort for the level III reliability method is only slightly more than used in a full level I method. For new kind of structures and/or materials, where there is only little experience, a level III methods is then to be preferred above the level I method because it gives direct insight into the structural reliability and decisive parameters. Besides the structures will either be safer or more economically build in comparison to structures designed using the level I safety factors

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2 

Test methods for on site measurement of resistivity of concrete. A RILEM TC154 Technical Recommendation
This paper describes methods to assess concrete resistivity on site for various purposes related to corrosion and protection of reinforcement. It is based on a first draft of a RILEM Technical Recommendation. The electrical resistivity of concrete can be related to the two processes involved in corrosion of reinforcement: initiation (chloride penetration) and propagation (corrosion rate). The resistivity of a structure exposed to chloride indicates the risk of early corrosion damage, because a low resistivity is related to rapid chloride penetration and to a high corrosion rate. Once damage has occurred, resistivity is relevant for electrochemical maintenance methods. The resistivity of the near surface concrete can be measured nondestructively by placing electrodes on the concrete surface, applying a voltage and measuring the current. Several arrangements can be used: one electrode (the reinforcement is the second electrode), two electrodes, four electrodes. Practical aspects of these arrangements are discussed. Procedures for calibration are proposed. Guidelines for the interpretation and reference values for various exposures and concrete compositions are given

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3 

Definitiestudie kennisinstrumentarium voor energie en emissies : verkenning naar de opbouw van een gezamenlijke kennisstructuur voor RIVM en ECN ECNRIVM/00002


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4 

Natural attenuation of benzene as evidenced by isotope analysis

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5 

Testretest reliability and intermethod agreement of a webbased questionnaire on work postures and workstation characteristics
Questionnaires are widely used to assess for nonneutral work postures in order to prevent upper extremity disorders among office workers. From previous research we know that the agreement between questionnaires and objective measurements for assessi ng work postures and workstation characteristics among office workers is low. One of the recommendations of previous research was to add pictures to increase clarity. Hence, we developed a webbased questionnaire in which pictures were added. Questionnaire items concerned both work postures and workstation characteristics. We investigated testretest reliability and agreement with observations and measurements with a manual goniometer. The study population consisted of 84 office workers of a research department. Questionnaire items regarding workstation characteristics showed sufficient testretest reliability and agreement with observation. Questions regarding work postures showed poor agreement with the observations. None of the questions showed good agreement with the manual goniometer measurements. The conclusion of this study is that our questionnaire cannot validly measure work postures, despite the added pictures. Efforts should be directed to objective measurements if one wants to validly measure work postures among office workers.

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6 

Observing with the ISO ShortWavelength Spectrometer
article 
1996

Author: 
Graauw, T. de
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Haser, L.N.
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Beintema, D.A.
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Roelfsema, P.R.
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Agthoven, H. van
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Barl, L.
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Bauer, O.H.
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Bekenkamp, H.E.G.
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Boonstra, A.J.
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Boxhoorn, D.R.
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Coté, J.
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Groene, P. de
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Dijkhuizen, C. van
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Drapatz, S.
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Evers, J.
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Feuchtgruber, H.
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Frericks, M.
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Genzel, R.
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Haerendel, G.
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Heras, A.M.
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Hucht, K.A. van der
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Hulst, T. van der
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Huygen, R.
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Jacobs, H.
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Jakob, G.
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Kamperman, Th.
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Katterloher, R.O.
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Kester, D.J.M.
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Kunze, D.
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Kussendrager, D.
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Lahuis, F.
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Lamers, H.J.G.L.M.
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Leech, K.
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Lei, S. van der
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Linden, R. van der
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Luinge, W.
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Lutz, D.
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Melzner, F.
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Morris, P.W.
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Nguyen, D. van
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Ploeger, G.
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Price, S.
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Salama, A.
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Schaeidt, S.G.
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Sijm, N.
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Smoorenburg, C.
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Spakman, J.
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Spoon, H.
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Steinmayer, M.
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Stoecker, J.
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Valentijn, E.A.
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Vandenbussche, B.
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Visser, H.
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Waelkens, C.
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Waters, L.B.F.M.
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Wensink, J.
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Wesselius, P.R.
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Wiezorrek, E.
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Wieprecht, E.
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Wijnbergen, J.J.
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Wildeman, K.J.
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Young, E.

Keywords: 
Instruments · Infrared: general · Instrumentation: spectrographs · Methods: data analysis · Methods: observational · Techniques: spectroscopic

The ShortWavelength Spectrometer (SWS) is one of the four instruments onboard ESA's Infrared Space Observatory (ISO), launched on November 17, 1995. The spectrometer covers the wavelength range of 2.38 to 45.2 μm with a spectral resolution ranging from 1000 to 2000. By inserting FabryPerot filters the resolution can be enhanced by a factor 20 for the wavelength range from 11.4 to 44.5 μm. An overview is given of the instrument, its inorbit calibration, performance, observing modes and offline processing software.

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7 

SpeedUp of the Monte Carlo Method by Using a Physical Model of the DempsterShafer Theory
By using the Monte Carlo method, we can obtain the minimum value of a function V(r) that is generally associated with the potential energy. In this paper we present a method that makes it possible to speed up the classical Monte Carlo method. The new method is based on the observation that the Bolzmann transition probability and the concept of local thermodynamical equilibrium give rise to an initial state of maximum entropy, which is subsequently modified by using the information on the internal structure of the system. The classical thermodynamic model does not take into account any structures inside the system, and therefore in many cases does not accurately model the system itself. In an attempt to take into account the internal structure of the system, we propose a physical model of the belief measure as defined in the DempsterShafer theory. The recent discovery by Resconi of an algorithm to calculate the probability distribution that has previously been developed by Harmanec and Klir, and which is consistent with the belief measure, opens the way to utilizing the Bolzmann distribution not only with a uniform distribution of probability, but instead with an arbitrary distribution of probability to guide the Monte Carlo iterative method to obtain the global minimum value of the potential energy. Starting from local thermodynamic equilibrium (i.e., local symmetry), the algorithm computes a new distribution over subsystems, resulting in a nonuniform distribution and in symmetry breaking. In the general case one can start with a different initial distribution induced by other local symmetries, corresponding to specific differential equations (e.g., the FokkerPlanck equation) and calculate from this the global distribution corresponding to the breaking of local symmetry. © 1998 John Wiley & Sons, Inc.

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8 

Evaluation of the Radiation Efficiency and the Noise Temperature of LowLoss Antennas
An accurate evaluation of the noise temperature of noncooled antenna systems is of great importance, particularly if the specifications of the antenna alone are a fewKelvins as in applications for radio astronomy. This evaluation requires an accurate analysis of the radiation efficiency, which we evaluate through the computation of the dissipated power from a methodofmoments (MoM) solution.We examine the numerical accuracy and the mesh sensitivity of the computed efficiency. Moreover we show that the efficiency is numerically smaller than or equal to 100%, contrary to results obtained with several commercial solvers. To describe the antenna loss, we employ the surface impedance of a thin sheet. For arrays of loops and for a taperedslot antenna (TSA), we compare our efficiency results with those obtained by commercial solvers and by numerical farfield integration for the radiated power.

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9 

Probleemdefiniëring bij organisatieveranderingen; Hoe methoden uit de Operations Research hieraan kunnen bijdragen
Verandertrajecten in organisaties vinden hun oorsprong vaak in complexe problemen. Om een oplossing te vinden en te implementeren is het eerst en vooral zaak om scherp te krijgen wat het probleem feitelijk is. Alleen dan is het mogelijk een adequate oplossing te vinden. Een onjuist of onvolledig inzicht in het probleem leidt (vaak) tot een onjuiste of onvolledige oplossing. Implementeren van deze oplossing kost vervolgens wel veel tijd en energie, maar heeft weinig kans op succes. Het echte probleem is immers niet opgelost! Vanuit de Operations Research is een scala van methoden beschikbaar die zich speciaal richten op het definiëren van problemen, Problem Structuring Methods genaamd. Gebruik van deze methoden leidt doorgaans tot een goede definiëring en oplossing van het probleem, naast het feit dat deze oplossing gedragen wordt door de diverse betrokken partijen. Dit artikel geeft inzicht in de werking van dit soort methoden en daarmee hopelijk een aanzet tot meer gebruik ervan in verandertrajecten.

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10 

Collective Training  Collective Thinking : Using Innovative Adaptive Simulation in Exercises
Joint Project Optic Windmill (JPOW) is the leading exercise in Joint Air and Missile Defence (JAMD) with many international participants (US, NL, GE, IT, NO …). Since JPOW3 (1998) TNO has supported the armed forces, both Dutch and foreign in JPOW. Typical JPOW objectives are the testing and development of new concepts, tactics and procedures in air and missile defence with existing and future capabilities. Simulation has proven to be an essential tool in the live, virtual and constructive environment of JPOW. We have created a simulation suite consisting of many tools and applications, JROADS, that enables us to provide realtime, operator in the loop exercise support, operational analysis and a test environment for hardware in the loop. This paper describes how to use innovative, scalable and flexible simulation technology to aid armed forces in achieving their objectives, starting with assessing the required level of fidelity and functionality needed for these objectives. We present an iterative approach to exercise support: extensive knowledge and research both before and during the exercise leads to the creation of new tools and agile adaptation of existing software. Likewise knowledge and tools created in other domains and areas feed back into the way we support exercises. The combination of such knowledge in operational analysts and an extensive range of tools make the difference over exercise participation with COTS simulations / tools.

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11 

Relevancebased evaluation of alignment approaches: The OAEI2007 food task revisited
Current stateoftheart ontologyalignment evaluation methods are based on the assumption that alignment relations come in two flavors: correct and incorrect. Some alignment systems find more correct mappings than others and hence, by this assumption, they perform better. In practical applications however, it does not only matter how many correct mappings you find, but also which correct mappings you find. This means that, apart from correctness, relevance should also be included in the evaluation procedure. In this paper we expand the samplebased evaluation of the OAEI 2007 food task with a sample evaluation that uses relevance to prototypical search tasks as a selection criterion for the drawing of sample mappings.

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12 

No significant effects of lutein, lycopene or ßcarotene supplementation on biological markers of oxidative stress and LDL oxidizability in healthy adult subjects
article 
2001

Author: 
Hininger, I.A.
·
MeyerWenger, A.
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Moser, U.
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Wright, A.
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Southon, S.
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Thurnham, D.
·
Chopra, M.
·
Berg, H. van den
·
Olmedilla, B.
·
Favier, A.E.
·
Roussel, A.M.

Keywords: 
Biology · DVB · DIGITAL TELEVISION · MPEG2 · SATELLITES · MEASUREMENT METHODS



13 

Hybrid modeling of crash dummies for numerical simulation
In crash dummy models two different mathematical formulations can be distinguished: multibody techniques and finite element techniques. Both approaches offer their specific advantages and disadvantages. Multibody techniques are particularly attractive for the simulation of crash dummy segment motions and complex joint behavior. Finite element techniques allow the calculation of local deformations in dummy segments. The use of combined multibody and finite element techniques, the socalled hybrid approach, allows the user to benefit from the capabilities of both approaches and offers the flexibility of merging more global models with, whenever needed, detailed representations of certain parts in the model. In this paper the strategy for hybrid modeling is illustrated. Several examples of recently developed and validated hybrid models will be presented in order to demonstrate the potential of this technique. In the examples flexible bodies and arbitrary shaped contact surfaces are shown to be efficient and accurate alternatives to traditional modeling methods. Criteria which can guide the user in the selection of the optimal setup of a crash dummy model are formulated and future developments are indicated.

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14 

Test methods for the evaluation of the in situ performance of waterrepellent treatments
TNO (TNO Building and Construction Research, Delft) , IRPAKIK (Royal Institute for the Cultural Ileritage, Brussels), and PDM (Politecnico Department of Structural Engineering, Milan) are involved in an EC research project 'Evaluation of the Performance of Surface Treatments for the Conservation of llistoric Brick Masonry'. Among the tasks in this project are: (a) to carry out 60 case studies of treated brick masonry monuments, in order to evaluate the performance, to collect knowledge on types of damage, darnaging processes and causes of damage and to fInd out about the relation between treatment and damage, and (b) to evaluate and improve test methods and eventually develop new methods or procedures. For two of the test methods, meant to assess the performance and to diagnose the damage, a proposal is presented and discuseed

[Abstract]

15 

Methods based on maximum holding time for evaluation of working postures


16 

Reduced Kernel IE's for MEN Based Analysis of Multilayered FSS Structures
Despite the fact that the general behavior of periodic structures has been investigated for many decades, the analysis and design of multilayered FSS's is still a very actual and complicated problem. This is especially true for stringent requirements, which rise for example when the FSS has to be integrated with a planar phased array. A MEN based approach has been developed to solve this specific kind of problems and successfully applied to a realistic design case [1]. The key innovative notion introduced by the MEN method is the formalization of the scattering problem through a set of Integral Equations (IE's) with reduced kernel and corresponding reduced Green's Function (GF). Originally, the pertinent Method of Moments (MoM) based IE's have been solved by expanding the unknowns in terms of subdomain functions. However, when the frequency filtering performances required from the FSS include steep roll offs and wide scan angles, the number of accessible (interacting) modes to be included in the analysis grows and it turns out that, for expansions based on subdomain functions, the MoM matrix tends to be ill conditioned. This specific behavior will be the subject of this contribution.

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17 

Powers synthesis of array antennas using the continuation method on far field phase distribution
We present a technique, based on the continuation method, to face power synthesis problems for array antennas. By using the least squares method (LSM), the power synthesis problem reduces to the minimization of an objective functional, which represents the square of the distance between the required and actual complex radiation pattern. Exploiting the GramSchmidt method (GSM) and the constrained minimization theory, the objective functional can be turned into a Lagrangian functional, which depends only on the radiation phase distribution. We use an iterative procedure for the optimization of the Lagrangian functional and we also introduce a continuation method to improve the reliability and robustness of the algorithm with respect to spurious solutions. Numerical simulations show better performance of the proposed algorithm, in terms of mean square error, than iterative least square synthesis (ILSS), although a slightly higher computational effort is required.

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18 

A TwoStage Method for Determining the Position and Corresponding Precision of Marine Mammal Sounds; 2004BU1OT
Today there is a concern that manmade sounds, such as that from sonar experiments, seismic operations and oil rigs, affect marine mammals. Detection and localisation of marine mammals will definitely support measures to reduce the possible detrimental effects. This paper presents a twostage localisation method, which is applied to data collected with an array of five hydrophones moored to the seabed in the Bay of Fundy, Canada. The array forms a 14 by 14 km square with one hydrophone in the centre. The method makes use of the relative travel times of the mammal's sound to the four hydrophones at the square vertices with respect to the travel time to the central hydrophone. First, a good initial position is obtained using hyperbolic fixing. In the second step the solution is improved in an iterative process, where each iteration determines the leastsquares solution of the set of four linearized equations for the measured relative travel times. Calculating the error ellipse from the covariance matrix of the solution provides the localisation accuracy. There are several parameters that affect the source position accuracy. These include the uncertainties in arrival times, sound speed and receiver positions. Their effect on the localisation accuracy is assessed.

[Abstract]

19 

The deflation accelerated schwarz method for CFD
Accurate simulation of glass melting furnaces requires the solution of very large linear algebraic systems of equations. To solve these equations efficiently a Schwarz domain decomposition (multiblock) method can be used. However, it can be observed that the convergence of the Schwarz method deteriorates when a large number of subdomains is used. This is due to small eigenvalues arising from the domain decomposition which slow down the convergence. Recently, a deflation approach was proposed to solve this problem using constant approximate eigenvectors. This paper generalizes this view to piecewise linear vectors and results for two CFD problems are presented. It can be observed that the number of iterations and wall clock time decrease considerably. The reason for this is that the norm of the initial residual is much smaller and the rate of convergence is higher.

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20 

Forearm arterial pressurevolume relationships in man
Pressurevolume (pV) relationships of a segment of the forearm circulation have been measured in nine male healthy subjects. Forearm volume was measured using electrical impedance plethysmography, arterial transmural pressure by subtracting mean arterial pressure measured contralaterally in a finger from the pressure in a cuff placed over the sensing electrodes of the plethysmograph. A special twophase measurement waveform was designed with which cuff pressure was first increased step wise to a suprasystolic level and held at that level for 120 s, then ramped down to zero pressure in another 300 s. The step phase inflation allowed us to estimate the parameters of the interstitial liquids and total blood compartments. The total blood compartment amounted to 6.2 ml per 100 ml of tissue. The ramp phase deflation allowed us to discriminate between a first phase in which only the arteries refilled and a second phase in which the veins also distended. An arctangent function was fitted to the first phase arterial pV relationship, describing it in model form. Total arterial volume per 100 ml of tissue amounted to 3.8 ml at physiological pressures, total arterial compliance of the forearm per centimetre length to 19.5 microliter kPa1 cm1 (2.6 microliter mmHg1 cm1) at physiological pressures, and to 340 microliter kPa1 cm1 (45 microliter mmHg1 cm1) maximum compliance at the lower, inflection point pressures. These values are in general agreement with the literature. Pulse wave velocity cannot be computed reliably from these data.

[Abstract]
