Evaluation of 2D Seismic Site Response due to Hill-Cavity Interaction Using Boundary Element Technique

This paper deals with the evaluation of two-dimensional site-effects due to the seismic interaction between hills with various configurations and underground cavities. The time-domain boundary element method is used to evaluate the site-effects of hill-cavity interaction subjected to vertically propagating in-plane SV and P waves. The presence of an underground cavity and the hill topography are expected to induce significant effects on the surface ground motion. To further examine the contribution of the amplification ratio of the hill-cavity system, a fairly simple approach, which can compute the response spectra of the hill’s surface motion above a cavity based on the real input motions, is also used to input motions.     

A Linguistic Survey of Khorasan: Implications for Language Isolation,Language Change,and Contact Linguistics

This paper describes and analyzes data from a number of Modern Iranian dialects spoken in Khorasan in the east of Iran which are unusual among the other Western Iranian languages in that they have grammaticalized a split tense-sensitive alignment in indexation, compared to other Iranian languages whose indexation splitness is sensitive to both tense and transitivity. These dialects are the former dialect of Birjand in the late nineteenth and early twentieth century, the present-day dialect of Ferdows, Khanik, and Se-Ghal’e. The findings are put in the context of the available data from the Classical Persian texts to show that the tense-sensitive splitness mentioned above is traceable in those texts. A number of external factors are discussed which seem to have been influential in the restructuring of the split-alignment of the former dialect of Birjand into a uniformly nominative-accusative alignment in terms of indexation as observed in the present-day dialect of Birjand. It is proposed that this restructuring is an instance of simplification. The three other dialects cited above are endangered in the sense that they can undergo the same kind of restructuring as happened to the dialect of Birjand.     

Multi‐Domain User‐Generated Content Based Model to Enrich Road Network Data for Multi‐Criteria Route Planning

By utilizing today's web‐based technologies, people can act as sensors and share their perceptions, emotions and observations in a variety of data forms, such as images, videos, texts, Global Positioning System (GPS) trajectories and maps. These forms are collectively called user‐generated content (UGC). These data are in different domains and have a multi‐modality nature. Although recent efforts have probed the acquisition of local knowledge by using single‐domain UGC data in specific applications, such efforts have not thus far presented a model considering multi‐domain UGC specifically to enrich road network data. This article aims at presenting such a model wherein, with the help of each data domain of UGC, one aspect of people knowledge about the road segment is obtained. These different aspects of knowledge are integrated using a Skyline operator to support multi‐criteria route finding. We name this model ERSBU (enriching road segments based on UGC). In ERSBU, road segments are basic spatial units, and their subjective properties have been extracted by using available UGC. The scenic score for each road segment was computed by using geo‐tagged Panoramio photos. The accessibility level of each road segment to different facilities was calculated based on data captured from Wikimapia and OpenStreetMap. Moreover, for measuring the movement popularity of each road segment, Wikiloc and Everytrail GPS trajectories were utilized. For the implementation of the ERSBU model, Tehran region 6 was considered the case study area. The Evaluation of the results proved that road segments that achieved a high score based on knowledge extracted from UGC also mostly gained top scores by analyzing traditional maps. ERSBU allows users to accomplish more‐qualitative path finding by considering the multi‐view characteristics of road segments.     

Environmental influences on skilled worker migration from Bangladesh to Canada

We conducted focus groups in Toronto with 44 recent skilled worker immigrants from Bangladesh to explore whether their decisions to migrate to Canada may have been influenced by environmental problems. Previous research has documented how floods, cyclones, droughts, and seasonal precipitation variations affect rural‐urban migration patterns within Bangladesh, and to its neighbours. Most participants had not experienced such environmental hazards, having lived in Dhaka prior to migrating. However, Dhaka's ongoing problems with air and water pollution, sanitation, lack of green space, and food adulteration were cited by 70% as being relevant considerations for the decision to migrate. The degree of influence varied considerably among participants. Roughly 16% said pollution was their primary motivation for leaving, household members having suffered from illnesses traceable to air pollution or poor sanitation. Another 54% stated that Dhaka's environmental problems were part of a wider range of quality‐of‐life concerns that had some influence on their decision. The findings suggest that current migration to Canada is not connected with environmental migration that takes place within Bangladesh, but that urban environmental problems combined with other social, economic, and political factors can help drive migration.     

Experimental Evaluation of Seismically and Non-Seismically Detailed External RC Beam-Column Joints

An experimental investigation was undertaken to study the seismic performance of external reinforced concrete (RC) beam-column joints having representative details for mid-rise RC frame buildings in developing countries such as Iran that were designed and constructed prior to the 1970s. Three half-scale external RC beam-column joints were tested by applying lateral cyclic loading of increasing amplitudes. Tested specimens were comprised of one unit having seismic reinforcement detailing in accordance with the seismic requirements of ACI 318-11, and two units having non-seismic reinforcement detailing in accordance with the 1970s construction practice in many developing countries, such as Iran. Two typical defects were considered for the non-seismic units, being the absence of transverse steel hoops and insufficient bond capacity of beam bottom reinforcing bars in the joint region. Test results indicated that the non-seismically detailed specimens had a high rate of strength and stiffness degradation when compared to the seismically detailed specimen, which was attributed primarily to the joint shear failure or bond failure of the beam bottom bars. The non-seismically detailed specimens also showed a 30% reduction in both average strength and ductility and a 60% loss of energy dissipation capacity in comparison to the seismically detailed specimen.     

Effects of Base and Lift Joints on the Dynamic Response of Concrete Gravity Dams to Pulse-Like Excitations

Near-fault earthquakes with forward-directivity effects produce pulse-like excitations. This article studies the dynamic response of monolithic and cracked sections of gravity dam under symmetric and anti-symmetric pulse-like excitations. The pulses are generated by the modified Gabor Wavelet transform. Two main characteristics of the pulses are pulse period and amplitude. The prescribed cracks are located along the base and two distinct lift joints through the dam body. The dam is modeled along with its reservoir using finite element method. The effects of base and lift joints, pulses shape, period, and amplitude, and reservoir height on the dam dynamic response are studied.