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Floor Level (floor + level)

Distribution by Scientific Domains

Engineering	50%
Psychology	33%

Selected Abstracts

A modal pushover analysis procedure to estimate seismic demands for unsymmetric-plan buildings

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2004
Anil K. Chopra
Abstract An Erratum has been published for this article in Earthquake Engng. Struct. Dyn. 2004; 33:1429. Based on structural dynamics theory, the modal pushover analysis (MPA) procedure retains the conceptual simplicity of current procedures with invariant force distribution, now common in structural engineering practice. The MPA procedure for estimating seismic demands is extended to unsymmetric-plan buildings. In the MPA procedure, the seismic demand due to individual terms in the modal expansion of the effective earthquake forces is determined by non-linear static analysis using the inertia force distribution for each mode, which for unsymmetric buildings includes two lateral forces and torque at each floor level. These ,modal' demands due to the first few terms of the modal expansion are then combined by the CQC rule to obtain an estimate of the total seismic demand for inelastic systems. When applied to elastic systems, the MPA procedure is equivalent to standard response spectrum analysis (RSA). The MPA estimates of seismic demand for torsionally-stiff and torsionally-flexible unsymmetric systems are shown to be similarly accurate as they are for the symmetric building; however, the results deteriorate for a torsionally-similarly-stiff unsymmetric-plan system and the ground motion considered because (a) elastic modes are strongly coupled, and (b) roof displacement is underestimated by the CQC modal combination rule (which would also limit accuracy of RSA for linearly elastic systems). Copyright © 2004 John Wiley & Sons, Ltd. [source]

Analysis of the gutta-percha filled area in C-shaped mandibular molars obturated with a modified MicroSeal technique

INTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2009
R. Ordinola-Zapata
Abstract Aim, To analyse the gutta-percha filled area of C-shaped molar teeth root filled with the modified MicroSeal technique with reference to the radiographic features and the C-shaped canal configuration. Methodology, Twenty-three mandibular second molar teeth with C-shaped roots were classified according to their radiographic features as: type I , merging, type II , symmetrical and type III , asymmetrical. The canals were root filled using a modified technique of the MicroSeal system. Horizontal sections at intervals of 600 ,m were made 1 mm from the apex to the subpulpal floor level. The percentage of gutta-percha area from the apical, middle and coronal levels of the radiographic types was analysed using the Kruskal,Wallis test. Complementary analysis of the C-shaped canal configurations (C1, C2 and C3) determined from cross-sections from the apical third was performed in a similar way. Results, No significant differences were found between the radiographic types in terms of the percentage of gutta-percha area at any level (P > 0.05): apical third, type I: 77.04%, II: 70.48% and III: 77.13%, middle third, type I: 95.72%, II: 93.17%, III: 91.13% and coronal level, type I: 98.30%, II: 98.25%, III: 97.14%. Overall, the percentage of the filling material was lower in the apical third (P < 0.05). No significant differences were found between the C-shaped canal configurations apically; C1: 72.64%, C2: 79.62%, C3: 73.51% (P > 0.05). Conclusions, The percentage of area filled with gutta-percha was similar in the three radiographic types and canal configuration categories of C-shaped molars. These results show the difficulty of achieving predictable filling of the root canal system when this anatomical variation exists. In general, the apical third was less completely filled. [source]

Housing and Mental Health: A Review of the Evidence and a Methodological and Conceptual Critique

JOURNAL OF SOCIAL ISSUES, Issue 3 2003
Gary W. Evans
Despite the fact that people invest more financial, temporal, and psychological resources in their homes than in any other material entity, research on housing and mental health is remarkably underdeveloped. We critically review existing research on housing and mental health, considering housing type (e.g., single-family detached versus multiple dwelling), floor level, and housing quality (e.g., structural damage). We then discuss methodological and conceptual shortcomings of this literature and provide a theoretical framework for future research on housing quality and mental health. [source]

Untersuchung des Wärmeschutzes von Außenecken über unbeheizten Kellern in Wohngebäuden , die Achillesferse von massiven Außenwänden mit äußerer Wärmedämmung?

BAUPHYSIK, Issue 4 2004
Christoph Geyer Dr. rer. nat.
Außenwände von Wohngebäuden werden häufig als massive Mauerwerkswände mit einer außenliegenden Wärmedämmung erstellt. Bei dieser Wandkonstruktion trennt aber der Mauerwerkssockel der massiven Außenwand im Erdgeschoß die Wärmedämmebene der Außenwand von der Wärmedämmebene der Kellerdecke über einem unbeheizten Keller. Hierdurch entsteht eine linienförmige Wärmebrücke. Die für den Mindestwärmeschutz kritischste Stelle tritt an der Außenecke im Erdgeschoß auf, wo sich je zwei dieser linienförmigen Wärmebrücken überlagern. Daher wird die minimale raumseitige Oberflächentemperatur an dieser Ecke für die Beurteilung des Mindestwärmeschutzes der Konstruktion herangezogen. Durch eine Vielzahl von dreidimensionalen Wärmebrückenberechnungen werden die Konstruktionseigenschaften der angrenzenden ebenen Bauteile herausgearbeitet, welche die minimale, raumseitige Oberflächentemperatur in der Außenecke über einem unbeheizten Keller und damit den Mindestwärmeschutz der Konstruktion beeinflussen. Es zeigt sich, daß eine minimale raumseitige Oberflächentemperatur in der Außenecke von 12, 6 °C erst mit Wärmedurchlaßwiderständen der Tragschale bzw. der gesamten Wandkonstruktion nachgewiesen werden kann, die wesentlich höher als 1, 2 m2K/W sind. Damit ist für diese Art von Außenwänden ein Mindestwärmeschutz nach Tabelle 3, DIN 4108-2 [1] mit einer Anforderung an den Wärmedurchlasswiderstand von R , 1,2 m2K/W nicht ausreichend, um den Mindestwärmeschutz auch für die Außenecke im Erdgeschoß rechnerisch nachweisen zu können. Es wird daher vorgeschlagen, ergänzende Hinweise in die Norm aufzunehmen. Examination of the thermal insulation characteristics of external corners above unheated basements in dwellings , the Achilles' heel of heavy-weight external walls with thermal insulation on the outside? External walls in dwellings consist often of a heavy-weight wall and a thermal insulation fixed outside. With this construction the insulation of the external wall is separated by the plinth of the external wall from the thermal insulation incorporated in the slab above an unheated basement. This results in a thermal bridge along the edge of the basement slab. The most critical point of the construction with regard to thermal protection occurs at the exterior corner at ground floor level, where two linear thermal bridges overlay. For this reason the minimum inner surface temperature of the corner is used to estimate the heat protection of the construction. A number of calculations of the minimum temperature at the interior surface of this three dimensional thermal bridge is performed to evaluate the parameters of the adjacent construction details which affect the minimum temperature at the inner surface of the corner. To reach the minimum temperature at he inner surface of the corner of 12.6 °C demanded by the German standard DIN 4108-2 as the minimum requirement of heat protection for thermal bridges, thermal resistances of the whole wall construction much higher than 1.2 m2K/W are necessary. For this construction type of exterior walls a thermal resistance of 1.2 m2K/W as demanded in table 3 of the German standard DIN 4108-2 as a minimum heat insulation for exterior walls can be shown to be insufficient to assure a minimum temperature of 12.6 °C at the inner surface of the corner at ground floor level. Thus it is proposed to add additional notes concerning this construction type in this standard. [source]

Parameter identification of torsionally coupled shear buildings from earthquake response records

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2008
Ganesh Hegde
Abstract This paper presents an efficient procedure to determine the natural frequencies, modal damping ratios and mode shapes for torsionally coupled shear buildings using earthquake response records. It is shown that the responses recorded at the top and first floor levels are sufficient to identify the dominant modal properties of a multistoried torsionally coupled shear building with uniform mass and constant eccentricity even when the input excitation is not known. The procedure applies eigenrealization algorithm to generate the state-space model of the structure using the cross-correlations among the measured responses. The dynamic characteristics of the structure are determined from the state-space realization matrices. Since the mode shapes are obtained only at the instrumented floor (top and first floors) levels, a new mode shape interpolation technique has been proposed to estimate the mode shape coefficients at the remaining floor levels. The application of the procedure has been demonstrated through a numerical experiment on an eight-storied torsionally coupled shear building subjected to earthquake base excitation. The results show that the proposed parameter identification technique is capable of identifying dominant modal parameters and responses even with significant noise contamination of the response records. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Are Young Children Susceptible to the False,Memory Illusion?

CHILD DEVELOPMENT, Issue 5 2002
C.J. Brainerd
False memories have typically been found to be more common during early childhood than during later childhood or adulthood. However, fuzzy,trace theory makes the counterintuitive prediction that some powerful forms of adult false memory will be greatly attenuated in early childhood, an important example being the Deese/Roediger/McDermott (DRM) illusion. Three developmental studies of this illusion (N=282) found that (1) it was at near,floor levels in young children, (2) it was still below adult levels by early adolescence, and (3) the low levels of the illusion in young children may be due to failure to "get the gist" of DRM materials. [source]