Displacement amplification factors for steel eccentrically braced frames

Inelastic deformation capacity of links is a factor that significantly influences design of steel eccentrically braced frames (EBFs). The link rotation angle is used to describe inelastic link deformation. The link rotation angle is generally calculated by making use of design story drifts that in turn are calculated by modifying the elastic displacements by a displacement amplification factor. This paper presents a numerical study undertaken to evaluate the displacement amplification factor given in ASCE7‐10 for EBFs and the rigid‐plastic mechanism used for calculating link rotation angles. A total of 72 EBFs were designed by considering the number of stories, the bay width, the link length to bay width ratio, and the seismic hazard level as the prime variables. All structures were analyzed using elastic and inelastic time history analyses. The results indicated that the displacement amplification factor given in ASCE7‐10 provides unconservative estimates of the story drifts. On the other hand, the rigid‐plastic mechanism provides conservative estimates of link rotations. Based on the results of the numerical study, a new set of displacement amplification factors that vary along the height of the structure and modifications to the rigid‐plastic mechanism were developed. In light of the proposed modifications, the EBFs were redesigned and analyzed using inelastic time history analysis. The results indicated that the proposed modifications provide improvements for the displacement amplification factor and link rotation angle calculation procedures. Copyright © 2014 John Wiley & Sons, Ltd.     

Separation of time scales in the HCA model for sand

Separation of time scales is used in a high cycle accumulation (HCA) model for sand. An important difficulty of the model is the limited applicability of the Miner’s rule to multiaxial cyclic loadings applied simultaneously or in a combination with monotonic loading. Another problem is the lack of simplified objective HCA formulas for geotechnical settlement problems. Possible solutions of these problems are discussed.     

CGCG 292-057: A Near-Distance Merger Galaxy with Double–Double Radio Lobes and X-shape Structure

J1159+5820 is an extended radio galaxy with a quite unusual morphology, featuring two pairs of radio lobes. Such sources, called double–double radio galaxies, constitute a very rare class of extragalactic radio sources. Furthermore, the extended radio structure of this source shows an X-shape form. According to a much likely scenario, such a morphology is due to interrupting nuclear activity in its central active galactic nucleus. Interestingly, the host of this source is a near-distance bright galaxy named CGCG 292-057, which is clearly disturbed, with tidal features and shells as plausible signs of a recent merger.     

ECHOBASE—A portable geographic fishery research database system

A geographic fishery research database system (GFRDBS), called ECHOBASE, for storing and management of data on pelagic fish resources from acoustic surveys and catch samples, combined with environmental data in a geographic context, has been developed. The system constitutes a portable and inexpensive yet powerful tool for fishery research and environmental monitoring and provides on‐board data processing and mapping capabilities.

Data are acquired from an echosounder, echo signal processor, environmental profiler (CTD probe), and Global Positioning System (GPS) receiver. The electronic digitized maps (based on C‐MAP public format files) provide active on‐screen nautical charts.

The basic GFRDBS platform is a portable PC 486 machine, which is used as an on‐board data acquisition and processing tool running under MS Windows 3.1 operating environment. The system is designed around the Borland's PARADOX package, which provides a relational database for managing acoustic, catch, and environmental data. The ECHOBASE programs were written in Borland C ++ language as a Windows application.     

Solution of the inverse geodetic problem for navigation

Abstract

Simplified geodetic formulas for very long and medium geodesies used in the sea and air navigation as well as methodology and formulas for investigating errors involved in these simplifictions for any hyperbolic system are presented.     

Modeling Electrical Field Distribution in Layered Geological Rock Formations with a Borehole Using the Coulomb Charges Method

The Coulomb charges method is used to model apparent resistivity measurements carried out in layered geological formations with a borehole using various devices. It is characterized by a high level of effectiveness and accuracy. The results are compared with the theoretical solutions for a homogenous medium with the borehole and invaded zone for point current source lateral devices. The relative error was less than 2% for different values of the range of the invaded zone and resistivity of invaded and true resistivity of formation.     

Magnetostratigraphic correlation of the Oxfordian–Kimmeridgian boundary

A magnetic polarity pattern for Boreal and Sub-Boreal ammonite zones of the Upper Oxfordian to Lower Kimmeridgian was established and confirmed in four British sections, including the proposed Global Boundary Stratotype Section and Point (GSSP) on the Isle of Skye (Scotland) to define the base of the international Kimmeridgian Stage. A coeval pattern for Sub-Mediterranean ammonite zones was compiled from seven sections in Poland, one German section and multi-section composites from France and Spain. The mean paleopole for the European Craton (excluding Spain) at the Oxfordian–Kimmeridgian boundary is 74.2°N, 181.3°E (Α₉₅ = 3.8°). The common magnetic polarity scale enables inter-correlation of ammonite subzones among these three faunal provinces and to the marine magnetic-anomaly M-Sequence. The proposed GSSP at the base of the Pictonia baylei Zone is near the base of an extended interval dominated by reversed polarity, which is interpreted to be Chron M26r. This GSSP level projects to the lower to middle part of the Epipeltoceras bimammatum Subzone, which is the middle subzone of this E. bimammatum Zone in the Sub-Mediterranean standard zonation. In contrast, the traditional placement of the Oxfordian–Kimmeridgian boundary in that Sub-Mediterranean standard zonation (base of Sutneria platynota Zone) is at the base of Chron M25r, or nearly 1 million years younger.     

Prospects for Scrutiny of Pulsars with Polish Part of LOFAR

LOFAR (LOw Frequency ARray) is a new generation digitally controlled radio telescope consisting of phased array antenna stations with sensitivity, bandwidth, range of frequency, and digital processing power that makes it an excellent tool for observations of pulsars. This interferometric instrument is able to work in a single-station mode as well as in group-of-selected-stations mode. This article discusses the great opportunity for conducting unique and independent research of pulsar sources with the three LOFAR stations located in Poland and maintained by the POLFAR consortium.     

Conservation of Korean Rural Heritage through the Use of Ecomuseums

Rural heritage that involves agricultural heritage could be critical to enhancing community identity through a conservational approach. The purpose of this research is to develop conservational methods for rural heritage that include agricultural heritage areas through the use of ecomuseums. To conduct the research, we first reviewed the concepts of ecomuseum and rural heritage. Secondly, we defined the concept of the Korean rural ecomuseum by taking into consideration the concept defined by Riviere, Globally Important Agricultural Heritage Systems (GIAHS), the rural heritage policy of Europe, and the agricultural heritage systems of Korea. Thirdly, we also describe methods that are applicable to Korean rural ecomuseums, which include type classification and components. Finally, we applied the ecomuseum concept to two pilot models in the Cheongsando and Gurae areas, both Korea Important Agricultural Heritage System (KIAHS) sites. We conclude that it is desirable to expand the range of targets for conservation from agricultural heritage to rural heritage areas. From this point of view, the rural ecomuseum can be a highly valuable tool that can help preserve agricultural heritage sites and neighboring areas. Furthermore, the ecomuseum can enhance community identities, and strengthen local economies.