Timing of metamorphism of the Lansang gneiss and implications for left-lateral motion along the Mae Ping (Wang Chao) strike-slip fault, Thailand

Science.gov (United States)

Palin, R. M.; Searle, M. P.; Morley, C. K.; Charusiri, P.; Horstwood, M. S. A.; Roberts, N. M. W.

2013-10-01

The Mae Ping fault (MPF), western Thailand, exhibits dominantly left-lateral strike-slip motion and stretches for >600 km, reportedly branching off the right-lateral Sagaing fault in Myanmar and extending southeast towards Cambodia. Previous studies have suggested that the fault assisted the large-scale extrusion of Sundaland that occurred during the Late Eocene-Early Oligocene, with a geological offset of ˜120-150 km estimated from displaced high-grade gneisses and granites of the Chiang Mai-Lincang belt. Exposures of high-grade orthogneiss in the Lansang National Park, part of this belt, locally contain strong mylonitic textures and are bounded by strike-slip ductile shear zones and brittle faults. Geochronological analysis of monazite from a sample of sheared biotite-K-feldspar orthogneiss suggests two episodes of crystallization, with core regions documenting Th-Pb ages between c. 123 and c. 114 Ma and rim regions documenting a significantly younger age range between c. 45-37 Ma. These data are interpreted to represent possible magmatic protolith emplacement for the Lansang orthogneiss during the Early Cretaceous, with a later episode of metamorphism occurring during the Eocene. Textural relationships provided by in situ analysis suggest that ductile shearing along the MPF occurred during the latter stages of, or after, this metamorphic event. In addition, monazite analyzed from an undeformed garnet-two-mica granite dyke intruding metamorphic units at Bhumipol Lake outside of the Mae Ping shear zone produced a Th-Pb age of 66.2 ± 1.6 Ma. This age is interpreted to date the timing of dyke emplacement, implying that the MPF cuts through earlier formed magmatic and high-grade metamorphic rocks. These new data, when combined with regional mapping and earlier geochronological work, show that neither metamorphism, nor regional cooling, was directly related to strike-slip motion.

Strike-slip linked core complexes: A new kinematic model of basement rock exhumation in a crustal-scale fault system

Science.gov (United States)

Meyer, Sven Erik; Passchier, Cees; Abu-Alam, Tamer; Stüwe, Kurt

2014-05-01

Metamorphic core complexes usually develop as extensional features during continental crustal thinning, such as the Basin and Range and the Aegean Terrane. The Najd fault system in Saudi Arabia is a 2000 km-long and 400 km-wide complex network of crustal-scale strike-slip shear zones in a Neoproterozoic collision zone. Locally, the anastomosing shear zones lead to exhumation of lower crustal segments and represent a new kinematic model for the development of core complexes. We report on two such structures: the Qazaz complex in Saudi Arabia and the Hafafit complex in Egypt. The 15 km-wide Qazaz complex is a triangular dome of gently dipping mylonitic foliations within the 140 km-long sinistral strike-slip Qazaz mylonite zone. The gneissic dome consists of high-grade rocks, surrounded by low-grade metasediments and metavolcanics. The main SE-trending strike-slip Qazaz shear zone splits southwards into two branches around the gneiss dome: the western branch is continuous with the shallow dipping mylonites of the dome core, without overprinting, and changes by more than 90 degrees from a NS-trending strike-slip zone to an EW-trending 40 degree south-dipping detachment that bounds the gneiss dome to the south. The eastern SE-trending sinistral strike-slip shear zone branch is slightly younger and transects the central dome fabrics. The gneiss dome appears to have formed along a jog in the strike-slip shear zone during 40 km of horizontal strike-slip motion, which caused local exhumation of lower crustal rocks by 25 km along the detachment. The eastern shear zone branch formed later during exhumation, transacted the gneiss dome and offset the two parts by another 70 km. The Hafafit core complex in Egypt is of similar shape and size to the Qazaz structure, but forms the northern termination of a sinistral strike-slip zone that is at least 100 km in length. This zone may continue into Saudi Arabia as the Ajjaj shear zone for another 100 km. The NW trending strike slip

Structural setting and kinematics of Nubian fault system, SE Western Desert, Egypt: An example of multi-reactivated intraplate strike-slip faults

Science.gov (United States)

Sakran, Shawky; Said, Said Mohamed

2018-02-01

Detailed surface geological mapping and subsurface seismic interpretation have been integrated to unravel the structural style and kinematic history of the Nubian Fault System (NFS). The NFS consists of several E-W Principal Deformation Zones (PDZs) (e.g. Kalabsha fault). Each PDZ is defined by spectacular E-W, WNW and ENE dextral strike-slip faults, NNE sinistral strike-slip faults, NE to ENE folds, and NNW normal faults. Each fault zone has typical self-similar strike-slip architecture comprising multi-scale fault segments. Several multi-scale uplifts and basins were developed at the step-over zones between parallel strike-slip fault segments as a result of local extension or contraction. The NNE faults consist of right-stepping sinistral strike-slip fault segments (e.g. Sin El Kiddab fault). The NNE sinistral faults extend for long distances ranging from 30 to 100 kms and cut one or two E-W PDZs. Two nearly perpendicular strike-slip tectonic regimes are recognized in the NFS; an inactive E-W Late Cretaceous - Early Cenozoic dextral transpression and an active NNE sinistral shear.

Role of N-S strike-slip faulting in structuring of north-eastern Tunisia; geodynamic implications

Science.gov (United States)

Arfaoui, Aymen; Soumaya, Abdelkader; Ben Ayed, Noureddine; Delvaux, Damien; Ghanmi, Mohamed; Kadri, Ali; Zargouni, Fouad

2017-05-01

Three major compressional events characterized by folding, thrusting and strike-slip faulting occurred in the Eocene, Late Miocene and Quaternary along the NE Tunisian domain between Bou Kornine-Ressas-Msella and Cap Bon Peninsula. During the Plio-Quaternary, the Grombalia and Mornag grabens show a maximum of collapse in parallelism with the NNW-SSE SHmax direction and developed as 3rd order distensives zones within a global compressional regime. Using existing tectonic and geophysical data supplemented by new fault-kinematic observations, we show that Cenozoic deformation of the Mesozoic sedimentary sequences is dominated by first order N-S faults reactivation, this sinistral wrench system is responsible for the formation of strike-slip duplexes, thrusts, folds and grabens. Following our new structural interpretation, the major faults of N-S Axis, Bou Kornine-Ressas-Messella (MRB) and Hammamet-Korbous (HK) form an N-S first order compressive relay within a left lateral strike-slip duplex. The N-S master MRB fault is dominated by contractional imbricate fans, while the parallel HK fault is characterized by a trailing of extensional imbricate fans. The Eocene and Miocene compression phases in the study area caused sinistral strike-slip reactivation of pre-existing N-S faults, reverse reactivation of NE-SW trending faults and normal-oblique reactivation of NW-SE faults, creating a NE-SW to N-S trending system of east-verging folds and overlaps. Existing seismic tomography images suggest a key role for the lithospheric subvertical tear or STEP fault (Slab Transfer Edge Propagator) evidenced below this region on the development of the MRB and the HK relay zone. The presence of extensive syntectonic Pliocene on top of this crustal scale fault may be the result of a recent lithospheric vertical kinematic of this STEP fault, due to the rollback and lateral migration of the Calabrian slab eastward.

A Study of Interactions Between Thrust and Strike-slip Faults

Directory of Open Access Journals (Sweden)

Jeng-Cheng Wang

2013-01-01

Full Text Available A 3-D finite difference method is applied in this study to investigate a spontaneous rupture within a fault system which includes a primary thrust fault and two strike-slip sub-faults. With the occurrence of a rupture on a fault, the rupture condition follows Coulomb¡¦s friction law wherein the stress-slip obeys the slip-weakening fracture criteria. To overcome the geometrical complexity of such a system, a finite difference method is encoded in two different coordinate systems; then, the calculated displacements are connected between the two systems using a 2-D interpolation technique. The rupture is initiated at the center of the main fault under the compression of regional tectonic stresses and then propagates to the boundaries whereby the main fault rupture triggers two strike-slip sub-faults. Simulation results suggest that the triggering of two sub-faults is attributed to two primary factors, regional tectonic stresses and the relative distances between the two sub-faults and the main fault.

Assemblage of strike-slip faults and tectonic extension and ...

Indian Academy of Sciences (India)

12

the formation, evolution and distribution of these strike-slip faults have important. 80 ...... function of coal-derived gas study for natural gas industry development in China; .... Bohai-Zhangjiakou seismotectonic zone based on 3D visco-elastic ...

Onset of aseismic creep on major strike-slip faults

KAUST Repository

Çakir, Ziyadin

2012-10-02

Time series analysis of spaceborne synthetic aperture radar (SAR) data, GPS measurements, and fi eld observations reveal that the central section of the Izmit (Turkey) fault that slipped with a supershear rupture velocity in the A.D. 1999, Mw7.4, Izmit earthquake began creeping aseismically following the earthquake. Rapid initial postseismic afterslip decayed logarithmically with time and appears to have reached a steady rate comparable to the preearthquake full fault-crossing rate, suggesting that it may continue for decades and possibly until late in the earthquake cycle. If confi rmed by future monitoring, these observations identify postseismic afterslip as a mechanism for initiating creep behavior along strike-slip faults. Long-term afterslip and/or creep has signifi cant implications for earthquake cycle models, recurrence intervals of large earthquakes, and accordingly, seismic hazard estimation along mature strike-slip faults, in particular for Istanbul which is believed to lie adjacent to a seismic gap along the North Anatolian fault in the Sea of Marmara. © 2012 Geological Society of America.

Onset of aseismic creep on major strike-slip faults

KAUST Repository

Ç akir, Ziyadin; Ergintav, Semih; Ö zener, Haluk; Doǧan, Uǧur; Akoglu, Ahmet; Meghraoui, Mustapha; Reilinger, Robert E.

2012-01-01

Time series analysis of spaceborne synthetic aperture radar (SAR) data, GPS measurements, and fi eld observations reveal that the central section of the Izmit (Turkey) fault that slipped with a supershear rupture velocity in the A.D. 1999, Mw7.4, Izmit earthquake began creeping aseismically following the earthquake. Rapid initial postseismic afterslip decayed logarithmically with time and appears to have reached a steady rate comparable to the preearthquake full fault-crossing rate, suggesting that it may continue for decades and possibly until late in the earthquake cycle. If confi rmed by future monitoring, these observations identify postseismic afterslip as a mechanism for initiating creep behavior along strike-slip faults. Long-term afterslip and/or creep has signifi cant implications for earthquake cycle models, recurrence intervals of large earthquakes, and accordingly, seismic hazard estimation along mature strike-slip faults, in particular for Istanbul which is believed to lie adjacent to a seismic gap along the North Anatolian fault in the Sea of Marmara. © 2012 Geological Society of America.

The role of post-collisional strike-slip tectonics in the geological evolution of the late Neoproterozoic volcano-sedimentary Guaratubinha Basin, southern Brazil

Science.gov (United States)

Barão, Leonardo M.; Trzaskos, Barbara; Vesely, Fernando F.; de Castro, Luís Gustavo; Ferreira, Francisco J. F.; Vasconcellos, Eleonora M. G.; Barbosa, Tiago C.

2017-12-01

The Guaratubinha Basin is a late Neoproterozoic volcano-sedimentary basin included in the transitional-stage basins of the South American Platform. The aim of this study is to investigate its tectonic evolution through a detailed structural analysis based on remote sensing and field data. The structural and aerogeophysics data indicate that at least three major deformational events affected the basin. Event E1 caused the activation of the two main basin-bounding fault zones, the Guaratubinha Master Fault and the Guaricana Shear Zone. These structures, oriented N20-45E, are associated with well-defined right-lateral to oblique vertical faults, conjugate normal faults and vertical flow structures. Progressive transtensional deformation along the two main fault systems was the main mechanism for basin formation and the deposition of thick coarse-grained deposits close to basin-borders. The continuous opening of the basin provided intense intermediate and acid magmatism as well as deposition of volcaniclastic sediments. Event E2 characterizes generalized compression, recorded as minor thrust faults with tectonic transport toward the northwest and left-lateral activation of the NNE-SSW Palmital Shear Zone. Event E3 is related to the Mesozoic tectonism associated with the South Atlantic opening, which generated diabase dykes and predominantly right-lateral strike-slip faults oriented N10-50W. Its rhomboidal geometry with long axis parallel to major Precambrian shear zones, the main presence of high-angle, strike-slip or oblique faults, the asymmetric distribution of geological units and field evidence for concomitant Neoproterozoic magmatism and strike-slip movements are consistent with pull-apart basins reported in the literature.

Geometry and kinematics of adhesive wear in brittle strike-slip fault zones

Science.gov (United States)

Swanson, Mark T.

2005-05-01

Detailed outcrop surface mapping in Late Paleozoic cataclastic strike-slip faults of coastal Maine shows that asymmetric sidewall ripouts, 0.1-200 m in length, are a significant component of many mapped faults and an important wall rock deformation mechanism during faulting. The geometry of these structures ranges from simple lenses to elongate slabs cut out of the sidewalls of strike-slip faults by a lateral jump of the active zone of slip during adhesion along a section of the main fault. The new irregular trace of the active fault after this jump creates an indenting asperity that is forced to plow through the adjoining wall rock during continued adhesion or be cut off by renewed motion along the main section of the fault. Ripout translation during adhesion sets up the structural asymmetry with trailing extensional and leading contractional ends to the ripout block. The inactive section of the main fault trace at the trailing end can develop a 'sag' or 'half-graben' type geometry due to block movement along the scallop-shaped connecting ramp to the flanking ripout fault. Leading contractional ramps can develop 'thrust' type imbrication and forces the 'humpback' geometry to the ripout slab due to distortion of the inactive main fault surface by ripout translation. Similar asymmetric ripout geometries are recognized in many other major crustal scale strike-slip fault zones worldwide. Ripout structures in the 5-500 km length range can be found on the Atacama fault system of northern Chile, the Qujiang and Xiaojiang fault zones in western China, the Yalakom-Hozameen fault zone in British Columbia and the San Andreas fault system in southern California. For active crustal-scale faults the surface expression of ripout translation includes a coupled system of extensional trailing ramps as normal oblique-slip faults with pull-apart basin sedimentation and contractional leading ramps as oblique thrust or high angle reverse faults with associated uplift and erosion. The

The 2005 - 2007 Bala (Ankara, central Turkey) earthquakes: a case study for strike-slip fault terminations

OpenAIRE

Esat, K.; Çivgin, B.; Kaypak, B.; Isik, V.; Ecevitoglu, B.; Seyitoglu, G.

2014-01-01

An intense seismic activity has been observed after the Bala (Ankara, NW central Turkey) earthquakes (30 July 2005: Mw=5.3, 20 December 2007: Mw=5.4, and 26 December 2007: Mw=5.3), continuing up to the present. The epicenters and the focal mechanism solutions of the earthquakes indicate that the right lateral strike-slip Afşar fault, trending N55-60°W, is responsible for the main shocks. The Afşar fault is thought to be the NW continuation of the Tuzgölü fault zone, which is one of the main n...

Characterization of Aftershock Sequences from Large Strike-Slip Earthquakes Along Geometrically Complex Faults

Science.gov (United States)

Sexton, E.; Thomas, A.; Delbridge, B. G.

2017-12-01

Large earthquakes often exhibit complex slip distributions and occur along non-planar fault geometries, resulting in variable stress changes throughout the region of the fault hosting aftershocks. To better discern the role of geometric discontinuities on aftershock sequences, we compare areas of enhanced and reduced Coulomb failure stress and mean stress for systematic differences in the time dependence and productivity of these aftershock sequences. In strike-slip faults, releasing structures, including stepovers and bends, experience an increase in both Coulomb failure stress and mean stress during an earthquake, promoting fluid diffusion into the region and further failure. Conversely, Coulomb failure stress and mean stress decrease in restraining bends and stepovers in strike-slip faults, and fluids diffuse away from these areas, discouraging failure. We examine spatial differences in seismicity patterns along structurally complex strike-slip faults which have hosted large earthquakes, such as the 1992 Mw 7.3 Landers, the 2010 Mw 7.2 El-Mayor Cucapah, the 2014 Mw 6.0 South Napa, and the 2016 Mw 7.0 Kumamoto events. We characterize the behavior of these aftershock sequences with the Epidemic Type Aftershock-Sequence Model (ETAS). In this statistical model, the total occurrence rate of aftershocks induced by an earthquake is λ(t) = λ_0 + \\sum_{i:t_i

Geologic Inheritance and Earthquake Rupture Processes: The 1905 M ≥ 8 Tsetserleg-Bulnay Strike-Slip Earthquake Sequence, Mongolia

Science.gov (United States)

Choi, Jin-Hyuck; Klinger, Yann; Ferry, Matthieu; Ritz, Jean-François; Kurtz, Robin; Rizza, Magali; Bollinger, Laurent; Davaasambuu, Battogtokh; Tsend-Ayush, Nyambayar; Demberel, Sodnomsambuu

2018-02-01

In 1905, 14 days apart, two M 8 continental strike-slip earthquakes, the Tsetserleg and Bulnay earthquakes, occurred on the Bulnay fault system, in Mongolia. Together, they ruptured four individual faults, with a total length of 676 km. Using submetric optical satellite images "Pleiades" with ground resolution of 0.5 m, complemented by field observation, we mapped in detail the entire surface rupture associated with this earthquake sequence. Surface rupture along the main Bulnay fault is 388 km in length, striking nearly E-W. The rupture is formed by a series of fault segments that are 29 km long on average, separated by geometric discontinuities. Although there is a difference of about 2 m in the average slip between the western and eastern parts of the Bulnay rupture, along-fault slip variations are overall limited, resulting in a smooth slip distribution, except for local slip deficit at segment boundaries. We show that damage, including short branches and secondary faulting, associated with the rupture propagation, occurred significantly more often along the western part of the Bulnay rupture, while the eastern part of the rupture appears more localized and thus possibly structurally simpler. Eventually, the difference of slip between the western and eastern parts of the rupture is attributed to this difference of rupture localization, associated at first order with a lateral change in the local geology. Damage associated to rupture branching appears to be located asymmetrically along the extensional side of the strike-slip rupture and shows a strong dependence on structural geologic inheritance.

A Possible Differentially Shortened Strike-slip Plate Boundary: the Okhotsk Plate Example.

Science.gov (United States)

Hindle, D.; Egorov, V.; Mackey, K. G.; Fujita, K.

2004-12-01

The Okhotsk plate has been postulated based on a combination of GPS geodetic inversions (REVEL1), seimsicity, geologic and lineament data. Lying between the North American and Eurasian plates, its northwestern corner would appear to be undergoing compression in a scissors motion between the two bounding plates. Extrusion tectonics along multiple, large strike-slip faults within the Okhotsk plate itself have been suggested to allow the escape of material away from the apex of Eurasia-North America. The plate boundary between Okhotsk and North America has been suggested to be diffuse, based on widely scattered minor seismicity. However, the large, left lateral, Ulakhan fault has also been suggested as a candidate plate boundary. We present field geological and geomorphological evidence of the partitioning of deformation between the Ulakhan fault, and several parallel and oblique, linked faults. The Ulakhan fault strand appears to have a maximum displacement of 24 km based on river valley offsets and closing large pull apart basins. Some of the displacement from the Ulakhan fault appears relayed into the plate margin along oblique trending, thrust/oblique slip faults. Estimated shortening over these faults is equivalent to the amount of shortening relayed into the plate margin from the plate boundary. There may be several thrust/oblique slip faults along the Ulakhan fault, which leads to the interesting situation of a segmented, strike-slip plate boundary being actively shortened in a margin parallel direction. This may be the result of postulated extrusion of the Okhotsk plate due to North America/Eurasia convergence. Such a situation would have important consequences for the interpretation of GPS data in a plate tectonic context.

Strike-slip pull-apart process and emplacement of Xiangshan uranium-producing volcanic basin

International Nuclear Information System (INIS)

Qiu Aijin; Guo Lingzhi; Shu Liangshu

2001-01-01

Xiangshan volcanic basin is one of the famous uranium-producing volcanic basins in China. Emplacement mechanism of Xiangshan uranium-producing volcanic basin is discussed on the basis of the latest research achievements of deep geology in Xiangshan area and the theory of continental dynamics. The study shows that volcanic activity in Xiangshan volcanic basin may be divided into two cycles, and its emplacement is controlled by strike-ship pull-apart process originated from the deep regional faults. Volcanic apparatus in the first cycle was emplaced in EW-trending structure activated by clockwise strike-slipping of NE-trending deep fault, forming the EW-trending fissure-type volcanic effusion belt. Volcanic apparatus in the second cycle was emplaced at junction points of SN-trending pull-apart structure activated by sinistral strike-slipping of NE-trending deep faults and EW-trending basement faults causing the center-type volcanic magma effusion and extrusion. Moreover, the formation mechanism of large-rich uranium deposits is discussed as well

Strike-slip tectonics and Quaternary basin formation along the Vienna Basin fault system inferred from Bouguer gravity derivatives

NARCIS (Netherlands)

Salcher, B. C.; Meurers, B.; Smit, J.; Decker, K.; HöLzel, M.; Wagreich, M.

2012-01-01

The Vienna Basin at the transition between the Alpine and Carpathian belt hosts a number of large Pleistocene sub-basins forming along an active continental scale strike-slip fault (Vienna Basin strike-slip fault). We utilize first-order derivatives from industrial Bouguer gravity data to unravel

Transition from strike-slip faulting to oblique subduction: active tectonics at the Puysegur Margin, South New Zealand

Science.gov (United States)

Lamarche, Geoffroy; Lebrun, Jean-Frédéric

2000-01-01

South of New Zealand the Pacific-Australia (PAC-AUS) plate boundary runs along the intracontinental Alpine Fault, the Puysegur subduction front and the intraoceanic Puysegur Fault. The Puysegur Fault is located along Puysegur Ridge, which terminates at ca. 47°S against the continental Puysegur Bank in a complex zone of deformation called the Snares Zone. At Puysegur Trench, the Australian Plate subducts beneath Puysegur Bank and the Fiordland Massif. East of Fiordland and Puysegur Bank, the Moonlight Fault System (MFS) represents the Eocene strike-slip plate boundary. Interpretation of seafloor morphology and seismic reflection profiles acquired over Puysegur Bank and the Snares Zone allows study of the transition from intraoceanic strike-slip faulting along the Puysegur Ridge to oblique subduction at the Puysegur Trench and to better understand the genetic link between the Puysegur Fault and the MFS. Seafloor morphology is interpreted from a bathymetric dataset compiled from swath bathymetry data acquired during the 1993 Geodynz survey, and single beam echo soundings acquired by the NZ Royal Navy. The Snares Zone is the key transition zone from strike-slip faulting to subduction. It divides into three sectors, namely East, NW and SW sectors. A conspicuous 3600 m-deep trough (the Snares Trough) separates the NW and East sectors. The East sector is characterised by the NE termination of Puysegur Ridge into right-stepping en echelon ridges that accommodate a change of strike from the Puysegur Fault to the MFS. Between 48°S and 47°S, in the NW sector and the Snares Trough, a series of transpressional faults splay northwards from the Puysegur Fault. Between 49°50'S and 48°S, thrusts develop progressively at Puysegur Trench into a decollement. North of 48°S the Snares Trough develops between two splays of the Puysegur Fault, indicating superficial extension associated with the subsidence of Puysegur Ridge. Seismic reflection profiles and bathymetric maps show a

Magmatic control along a strike-slip volcanic arc: The central Aeolian arc (Italy)

Science.gov (United States)

Ruch, J.; Vezzoli, L.; De Rosa, R.; Di Lorenzo, R.; Acocella, V.

2016-02-01

The regional stress field in volcanic areas may be overprinted by that produced by magmatic activity, promoting volcanism and faulting. In particular, in strike-slip settings, the definition of the relationships between the regional stress field and magmatic activity remains elusive. To better understand these relationships, we collected stratigraphic, volcanic, and structural field data along the strike-slip central Aeolian arc (Italy): here the islands of Lipari and Vulcano separate the extensional portion of the arc (to the east) from the contractional one (to the west). We collected >500 measurements of faults, extension fractures, and dikes at 40 sites. Most structures are NNE-SSW to NNW-SSE oriented, eastward dipping, and show almost pure dip-slip motion, consistent with an E-W extension direction, with minor dextral and sinistral shear. Our data highlight six eruptive periods during the last 55 ka, which allow considering both islands as a single magmatic system, in which tectonic and magmatic activities steadily migrated eastward and currently focus on a 10 km long × 2 km wide active segment. Faulting appears to mostly occur in temporal and spatial relation with magmatic events, supporting that most of the observable deformation derives from transient magmatic activity (shorter term, days to months), rather than from steady longer-term regional tectonics (102-104 years). More in general, the central Aeolian case shows how magmatic activity may affect the structure and evolution of volcanic arcs, overprinting any strike-slip motion with magma-induced extension at the surface.

Magmatic control along a strike-slip volcanic arc: The central Aeolian arc (Italy)

KAUST Repository

Ruch, Joel

2016-01-23

The regional stress field in volcanic areas may be overprinted by that produced by magmatic activity, promoting volcanism and faulting. In particular, in strike-slip settings, the definition of the relationships between the regional stress field and magmatic activity remains elusive. To better understand these relationships, we collected stratigraphic, volcanic and structural field data along the strike-slip Central Aeolian arc (Italy): here the islands of Lipari and Vulcano separate the extensional portion of the arc (to the east) from the contractional one (to the west). We collected >500 measurements of faults, extension fractures and dikes at 40 sites. Most structures are NNE-SSW to NNW-SSE oriented, eastward dipping, and show almost pure dip-slip motion; consistent with an E-W extension direction, with minor dextral and sinistral shear. Our data highlight six eruptive periods during the last 55 ka, which allow considering both islands as a single magmatic system, in which tectonic and magmatic activity steadily migrated eastward and currently focus on a 10 km long x 2 km wide active segment. Faulting appears to mostly occur in temporal and spatial relation with magmatic events, supporting that most of the observable deformation derives from transient magmatic activity (shorter-term, days to months), rather than from steady longer-term regional tectonics (102-104 years). More in general, the Central Aeolian case shows how magmatic activity may affect the structure and evolution of volcanic arcs, overprinting any strike-slip motion with magma-induced extension at the surface.

Effect of inherited structures on strike-slip plate boundaries: insight from analogue modelling of the central Levant Fracture System, Lebanon

Science.gov (United States)

Ghalayini, Ramadan; Daniel, Jean-Marc; Homberg, Catherine; Nader, Fadi

2015-04-01

Analogue sandbox modeling is a tool to simulate deformation style and structural evolution of sedimentary basins. The initial goal is to test what is the effect of inherited and crustal structures on the propagation, evolution, and final geometry of major strike-slip faults at the boundary between two tectonic plates. For this purpose, we have undertaken a series of analogue models to validate and reproduce the structures of the Levant Fracture System, a major NNE-SSW sinistral strike-slip fault forming the boundary between the Arabian and African plates. Onshore observations and recent high quality 3D seismic data in the Levant Basin offshore Lebanon demonstrated that Mesozoic ENE striking normal faults were reactivated into dextral strike-slip faults during the Late Miocene till present day activity of the plate boundary which shows a major restraining bend in Lebanon with a ~ 30°clockwise rotation in its trend. Experimental parameters consisted of a silicone layer at the base simulating the ductile crust, overlain by intercalated quartz sand and glass sand layers. Pre-existing structures were simulated by creating a graben in the silicone below the sand at an oblique (>60°) angle to the main throughgoing strike-slip fault. The latter contains a small stepover at depth to create transpression during sinistral strike-slip movement and consequently result in mountain building similarly to modern day Lebanon. Strike-slip movement and compression were regulated by steady-speed computer-controlled engines and the model was scanned using a CT-scanner continuously while deforming to have a final 4D model of the system. Results showed that existing normal faults were reactivated into dextral strike-slip faults as the sinistral movement between the two plates accumulated. Notably, the resulting restraining bend is asymmetric and segmented into two different compartments with differing geometries. One compartment shows a box fold anticline, while the second shows an

Strike-Slip Fault Deformation and Its Control in Hydrocarbon Trapping in Ketaling Area, Jambi Subbasin, Indonesia

Science.gov (United States)

Ramadhan, Aldis; Badai Samudra, Alexis; Jaenudin; Puji Lestari, Enik; Saputro, Julian; Sugiono; Hirosiadi, Yosi; Amrullah, Indi

2018-03-01

Geologically, Ketaling area consists of a local high considered as flexure margin of Tempino-Kenali Asam Deep in west part and graben in east part also known as East Ketaling Deep. Numerous proven plays were established in Ketaling area with reservoir in early Miocene carbonate and middle Miocene sand. This area underwent several major deformations. Faults are developed widely, yet their geometrical features and mechanisms of formation remained so far indistinct, which limited exploration activities. With new three-dimensional seismic data acquired in 2014, this area evidently interpreted as having strike-slip mechanism. The objective of this study is to examine characteristic of strike slip fault and its affect to hydrocarbon trapping in Ketaling Area. Structural pattern and characteristic of strike slip fault deformation was examined with integration of normal seismic with variance seismic attribute analysis and the mapping of Syn-rift to Post-rift horizon. Seismic flattening on 2D seismic cross section with NW-SE direction is done to see the structural pattern related to horst (paleohigh) and graben. Typical flower structure, branching strike-slip fault system and normal fault in synrift sediment clearly showed in section. An echelon pattern identified from map view as the result of strike slip mechanism. Detail structural geology analysis show the normal fault development which has main border fault in the southern of Ketaling area dipping to the Southeast-East with NE-SW lineament. These faults related to rift system in Ketaling area. NW-SE folds with reactive NE-SW fault which act as hydrocarbon trapping in the shallow zone. This polyphase tectonic formed local graben, horst and inverted structure developed a good kitchen area (graben) and traps (horst, inverted structure). Subsequently, hydrocarbon accumulation potentials such as basement fractures, inverted syn-rift deposit and shallow zone are very interesting to explore in this area.

Respecting the right to strike

CERN Multimedia

Staff Association

2015-01-01

Since two years the representatives of the employers in the ILO, a tripartite multilateral body responsible for guaranteeing the correct application of an international labour code, try to weaken the global work regulations. On the occasion of the Global Day of Action for the right to strike at the invitation of the Geneva community of Union action (Communauté genevoise d’action syndicale) and the Swiss Trade Union Association (Union syndicale suisse) around noon on Wednesday 18th February some fifty staff representatives of international organizations gathered on the place des Nations in Geneva to reaffirm the importance of this fundamental right, too often flouted. A delegation of the CERN Staff Association was also present. In a short speech, the Staff Association said that, while being one of the fundamental human rights, to be efficient the right to strike must be used intelligently. It must be implemented taking into account the sensitivities of the professional environment and r...

Rupture model of the 2015 M7.2 Sarez, Central Pamir, earthquake and the importance of strike-slip faulting in the Pamir interior

Science.gov (United States)

Metzger, S.; Schurr, B.; Schoene, T.; Zhang, Y.; Sudhaus, H.

2016-12-01

The Pamir mountain range, located in the Northwest of the India-Asia collision zone, accommodates approximately one third of the northward advance of the Indian continent at this longitude (i.e. 34 mm/yr) mostly by shortening at its northern thrust system. Geodetic and seismic data sets reveal here a narrow zone of high deformation and M7+ earthquakes of mostly thrust type with some dextral strike-slip faulting observed, too. The Pamir interior shows sinistral strike-slip and normal faulting indicating north-south compression and east-west extension. In this tectonic setting the two largest instrumentally recorded earthquakes, the M7+ 1911 and 2015 earthquake events in the central Pamir occurred with left-lateral shear along a NE-SW rupture plane. We present the co-seismic deformation field of the 2015 earthquake observed by Radar satellite interferometry (InSAR), SAR amplitude offsets and high-rate Global Positioning System (GPS). The InSAR and offset results reveal that the earthquake created a 50 km long surface rupture with maximum left-lateral offsets of more than two meters on a yet unmapped fault trace of the Sarez Karakul Fault System (SKFS). We further derive a distributed slip-model including a thorough model parameter uncertainty study. Using a two-step approach to first find the optimal rupture geometry and then invert for slip on discrete patches, we show that a data-driven patch resolution produces yields a better representation of the near-surface slip and an increased slip precision than a uniform patch approach without increasing the number of parameters and thus calculation time. Our best-fit model yields a sub-vertical fault plane with a strike of N39.5 degrees and a rupture area of 80 x 40 km2 with a maximum slip of 2 meters in the upper 10 km of the crust near the surface rupture. The 1911 and 2015 earthquakes demonstrate the importance of sinistral strike-slip faulting on the SKFS, contributing both to shear between the western and eastern

Stress near geometrically complex strike-slip faults - Application to the San Andreas fault at Cajon Pass, southern California

Science.gov (United States)

Saucier, Francois; Humphreys, Eugene; Weldon, Ray, II

1992-01-01

A model is presented to rationalize the state of stress near a geometrically complex major strike-slip fault. Slip on such a fault creates residual stresses that, with the occurrence of several slip events, can dominate the stress field near the fault. The model is applied to the San Andreas fault near Cajon Pass. The results are consistent with the geological features, seismicity, the existence of left-lateral stress on the Cleghorn fault, and the in situ stress orientation in the scientific well, found to be sinistral when resolved on a plane parallel to the San Andreas fault. It is suggested that the creation of residual stresses caused by slip on a wiggle San Andreas fault is the dominating process there.

The 2015 Mw7.2 Sarez Strike-Slip Earthquake in the Pamir Interior: Response to the Underthrusting of India's Western Promontory

Science.gov (United States)

Metzger, Sabrina; Schurr, Bernd; Ratschbacher, Lothar; Sudhaus, Henriette; Kufner, Sofia-Katerina; Schöne, Tilo; Zhang, Yong; Perry, Mason; Bendick, Rebecca

2017-11-01

The Pamir orogen, Central Asia, is the result of the ongoing northward advance of the Indian continent causing shortening inside Asia. Geodetic and seismic data place the most intense deformation along the northern rim of the Pamir, but the recent 7 December 2015, Mw7.2 Sarez earthquake occurred in the Pamir's interior. We present a distributed slip model of this earthquake using coseismic geodetic data and postseismic field observations. The earthquake ruptured an ˜80 km long, subvertical, sinistral fault consisting of three right-stepping segments from the surface to ˜30 km depth with a maximum slip of three meters in the upper 10 km of the crust. The coseismic slip model agrees well with en échelon secondary surface breaks that are partly influenced by liquefaction-induced mass movements. These structures reveal up to 2 m of sinistral offset along the northern, low-offset segment of modeled rupture. The 2015 event initiated close to the presumed epicenter of the 1911 Mw˜7.3 Lake Sarez earthquake, which had a similar strike-slip mechanism. These earthquakes highlight the importance of NE trending sinistral faults in the active tectonics of the Pamir. Strike-slip deformation accommodates shear between the rapidly northward moving eastern Pamir and the Tajik basin in the west and is part of the westward (lateral) extrusion of thickened Pamir plateau crust into the Tajik basin. The Sarez-Karakul fault system and the two large Sarez earthquakes likely are crustal expressions of the underthrusting of the northwestern leading edge of the Indian mantle lithosphere beneath the Pamir.

San Andreas-sized Strike-slip Fault on Europa

Science.gov (United States)

1998-01-01

This mosaic of the south polar region of Jupiter's moon Europa shows the northern 290 kilometers (180 miles) of a strike-slip fault named Astypalaea Linea. The entire fault is about 810 kilometers (500 miles) long, about the size of the California portion of the San Andreas fault, which runs from the California-Mexico border north to the San Francisco Bay. In a strike-slip fault, two crustal blocks move horizontally past one another, similar to two opposing lanes of traffic. Overall motion along the fault seems to have followed a continuous narrow crack along the feature's entire length, with a path resembling steps on a staircase crossing zones that have been pulled apart. The images show that about 50 kilometers (30 miles) of displacement have taken place along the fault. The fault's opposite sides can be reconstructed like a puzzle, matching the shape of the sides and older, individual cracks and ridges broken by its movements. [figure removed for brevity, see original site] The red line marks the once active central crack of the fault. The black line outlines the fault zone, including material accumulated in the regions which have been pulled apart. Bends in the fault have allowed the surface to be pulled apart. This process created openings through which warmer, softer ice from below Europa's brittle ice shell surface, or frozen water from a possible subsurface ocean, could reach the surface. This upwelling of material formed large areas of new ice within the boundaries of the original fault. A similar pulling-apart phenomenon can be observed in the geological trough surrounding California's Salton Sea, in Death Valley and the Dead Sea. In those cases, the pulled-apart regions can include upwelled materials, but may be filled mostly by sedimentary and eroded material from above. One theory is that fault motion on Europa is induced by the pull of variable daily tides generated by Jupiter's gravitational tug on Europa. Tidal tension opens the fault and

Late Quaternary strike-slip along the Taohuala Shan-Ayouqi fault zone and its tectonic implications in the Hexi Corridor and the southern Gobi Alashan, China

Science.gov (United States)

Yu, Jing-xing; Zheng, Wen-jun; Zhang, Pei-zhen; Lei, Qi-yun; Wang, Xu-long; Wang, Wei-tao; Li, Xin-nan; Zhang, Ning

2017-11-01

The Hexi Corridor and the southern Gobi Alashan are composed of discontinuous a set of active faults with various strikes and slip motions that are located to the north of the northern Tibetan Plateau. Despite growing understanding of the geometry and kinematics of these active faults, the late Quaternary deformation pattern in the Hexi Corridor and the southern Gobi Alashan remains controversial. The active E-W trending Taohuala Shan-Ayouqi fault zone is located in the southern Gobi Alashan. Study of the geometry and nature of slip along this fault zone holds crucial value for better understanding the regional deformation pattern. Field investigations combined with high-resolution imagery show that the Taohuala Shan fault and the E-W trending faults within the Ayouqi fault zone (F2 and F5) are left-lateral strike-slip faults, whereas the NW or WNW-trending faults within the Ayouqi fault zone (F1 and F3) are reverse faults. We collected Optically Stimulated Luminescence (OSL) and cosmogenic exposure age dating samples from offset alluvial fan surfaces, and estimated a vertical slip rate of 0.1-0.3 mm/yr, and a strike-slip rate of 0.14-0.93 mm/yr for the Taohuala Shan fault. Strata revealed in a trench excavated across the major fault (F5) in the Ayouqi fault zone and OSL dating results indicate that the most recent earthquake occurred between ca. 11.05 ± 0.52 ka and ca. 4.06 ± 0.29 ka. The geometry and kinematics of the Taohuala Shan-Ayouqi fault zone enable us to build a deformation pattern for the entire Hexi Corridor and the southern Gobi Alashan, which suggest that this region experiences northeastward oblique extrusion of the northern Tibetan Plateau. These left-lateral strike-slip faults in the region are driven by oblique compression but not associated with the northeastward extension of the Altyn Tagh fault.

The morphology of strike-slip faults - Examples from the San Andreas Fault, California

Science.gov (United States)

Bilham, Roger; King, Geoffrey

1989-01-01

The dilatational strains associated with vertical faults embedded in a horizontal plate are examined in the framework of fault kinematics and simple displacement boundary conditions. Using boundary element methods, a sequence of examples of dilatational strain fields associated with commonly occurring strike-slip fault zone features (bends, offsets, finite rupture lengths, and nonuniform slip distributions) is derived. The combinations of these strain fields are then used to examine the Parkfield region of the San Andreas fault system in central California.

Carpathian Shear Corridor – A strike-slip boundary of an extruded crustal segment

Czech Academy of Sciences Publication Activity Database

Marko, F.; Andriessen, P.A.M.; Tomek, Č.; Bezák, V.; Fojtíková, Lucia; Bošanský, M.; Piovarči, M.; Reichenwalder, P.

703-704, APR 22 (2017), s. 119-134 ISSN 0040-1951 Grant - others:Slovak Foundation Grant(SK) VEGA 2/0188/15 Institutional support: RVO:67985891 Keywords : extrusion * Neo-alpine evolution * strike-slip faulting * uplift history * Western Carpathians Subject RIV: DC - Siesmology, Volcanology, Earth Structure OBOR OECD: Geology Impact factor: 2.693, year: 2016

Tsunamis from strike-slip earthquakes in the Wharton Basin, northeast Indian Ocean: March 2016 Mw7.8 event and its relationship with the April 2012 Mw 8.6 event

Science.gov (United States)

Heidarzadeh, Mohammad; Harada, Tomoya; Satake, Kenji; Ishibe, Takeo; Takagawa, Tomohiro

2017-12-01

The Wharton Basin, off southwest Sumatra, ruptured to a large intraplate left-lateral strike-slip Mw 7.8 earthquake on 2016 March 2. The epicentre was located ∼800 km to the south of another similar-mechanism intraplate Mw 8.6 earthquake in the same basin on 2012 April 11. Small tsunamis from these strike-slip earthquakes were registered with maximum amplitudes of 0.5-1.5 cm on DARTs and 1-19 cm on tide gauges for the 2016 event, and the respective values of 0.5-6 and 6-40 cm for the 2012 event. By using both teleseismic body waves and tsunami observations of the 2016 event, we obtained optimum slip models with rupture velocity (Vr) in the range of 2.8-3.6 km s-1 belonging to both EW and NS faults. While the EW fault plane cannot be fully ruled out, we chose the best model as the NS fault plane with a Vr of 3.6 km s-1, a maximum slip of 7.7 m and source duration of 33 s. The tsunami energy period bands were 4-15 and 7-24 min for the 2016 and 2012 tsunamis, respectively, reflecting the difference in source sizes. Seismicity in the Wharton Basin is dominated by large strike-slip events including the 2012 (Mw 8.6 and 8.2) and 2016 (Mw 7.8) events, indicating that these events are possible tsunami sources in the Wharton Basin. Cumulative number and cumulative seismic-moment curves revealed that most earthquakes are of strike-slip mechanisms and the largest seismic-moment is provided by the strike-slip earthquakes in this basin.

States of stress and slip partitioning in a continental scale strike-slip duplex: Tectonic and magmatic implications by means of finite element modeling

Science.gov (United States)

Iturrieta, Pablo Cristián; Hurtado, Daniel E.; Cembrano, José; Stanton-Yonge, Ashley

2017-09-01

Orogenic belts at oblique convergent subduction margins accommodate deformation in several trench-parallel domains, one of which is the magmatic arc, commonly regarded as taking up the margin-parallel, strike-slip component. However, the stress state and kinematics of volcanic arcs is more complex than usually recognized, involving first- and second-order faults with distinctive slip senses and mutual interaction. These are usually organized into regional scale strike-slip duplexes, associated with both long-term and short-term heterogeneous deformation and magmatic activity. This is the case of the 1100 km-long Liquiñe-Ofqui Fault System in the Southern Andes, made up of two overlapping margin-parallel master faults joined by several NE-striking second-order faults. We present a finite element model addressing the nature and spatial distribution of stress across and along the volcanic arc in the Southern Andes to understand slip partitioning and the connection between tectonics and magmatism, particularly during the interseismic phase of the subduction earthquake cycle. We correlate the dynamics of the strike-slip duplex with geological, seismic and magma transport evidence documented by previous work, showing consistency between the model and the inferred fault system behavior. Our results show that maximum principal stress orientations are heterogeneously distributed within the continental margin, ranging from 15° to 25° counter-clockwise (with respect to the convergence vector) in the master faults and 10-19° clockwise in the forearc and backarc domains. We calculate the stress tensor ellipticity, indicating simple shearing in the eastern master fault and transpressional stress in the western master fault. Subsidiary faults undergo transtensional-to-extensional stress states. The eastern master fault displays slip rates of 5 to 10 mm/yr, whereas the western and subsidiary faults show slips rates of 1 to 5 mm/yr. Our results endorse that favorably oriented

Magma storage in a strike-slip caldera.

Science.gov (United States)

Saxby, J; Gottsmann, J; Cashman, K; Gutiérrez, E

2016-07-22

Silicic calderas form during explosive volcanic eruptions when magma withdrawal triggers collapse along bounding faults. The nature of specific interactions between magmatism and tectonism in caldera-forming systems is, however, unclear. Regional stress patterns may control the location and geometry of magma reservoirs, which in turn may control the spatial and temporal development of faults. Here we provide new insight into strike-slip volcano-tectonic relations by analysing Bouguer gravity data from Ilopango caldera, El Salvador, which has a long history of catastrophic explosive eruptions. The observed low gravity beneath the caldera is aligned along the principal horizontal stress orientations of the El Salvador Fault Zone. Data inversion shows that the causative low-density structure extends to ca. 6 km depth, which we interpret as a shallow plumbing system comprising a fractured hydrothermal reservoir overlying a magmatic reservoir with vol% exsolved vapour. Fault-controlled localization of magma constrains potential vent locations for future eruptions.

Structural characteristics and implication on tectonic evolution of the Daerbute strike-slip fault in West Junggar area, NW China

Science.gov (United States)

Wu, Kongyou; Pei, Yangwen; Li, Tianran; Wang, Xulong; Liu, Yin; Liu, Bo; Ma, Chao; Hong, Mei

2018-03-01

The Daerbute fault zone, located in the northwestern margin of the Junggar basin, in the Central Asian Orogenic Belt, is a regional strike-slip fault with a length of 400 km. The NE-SW trending Daerbute fault zone presents a distinct linear trend in plain view, cutting through both the Zair Mountain and the Hala'alate Mountain. Because of the intense contraction and shearing, the rocks within the fault zone experienced high degree of cataclasis, schistosity, and mylonization, resulting in rocks that are easily eroded to form a valley with a width of 300-500 m and a depth of 50-100 m after weathering and erosion. The well-exposed outcrops along the Daerbute fault zone present sub-horizontal striations and sub-vertical fault steps, indicating sub-horizontal shearing along the observed fault planes. Flower structures and horizontal drag folds are also observed in both the well-exposed outcrops and high-resolution satellite images. The distribution of accommodating strike-slip splay faults, e.g., the 973-pluton fault and the Great Jurassic Trough fault, are in accordance with the Riedel model of simple shear. The seismic and time-frequency electromagnetic (TFEM) sections also demonstrate the typical strike-slip characteristics of the Daerbute fault zone. Based on detailed field observations of well-exposed outcrops and seismic sections, the Daerbute fault can be subdivided into two segments: the western segment presents multiple fault cores and damage zones, whereas the eastern segment only presents a single fault core, in which the rocks experienced a higher degree of rock cataclasis, schistosity, and mylonization. In the central overlapping portion between the two segments, the sediments within the fault zone are primarily reddish sandstones, conglomerates, and some mudstones, of which the palynological tests suggest middle Permian as the timing of deposition. The deformation timing of the Daerbute fault was estimated by integrating the depocenters' basinward

A note on 2-D lithospheric deformation due to a blind strike-slip fault

Indian Academy of Sciences (India)

mic deformation. Several researchers have devel- oped models of coseismic lithospheric deformation. Rybicki (1971) found a closed-form analytical solu- tion for the problem of a long vertical strike-slip fault in a two-layer model of the earth. Chinnery and Jovanovich (1972) extended the solution to a three-layer model.

Effects of Strike-Slip Fault Segmentation on Earthquake Energy and Seismic Hazard

Science.gov (United States)

Madden, E. H.; Cooke, M. L.; Savage, H. M.; McBeck, J.

2014-12-01

Many major strike-slip faults are segmented along strike, including those along plate boundaries in California and Turkey. Failure of distinct fault segments at depth may be the source of multiple pulses of seismic radiation observed for single earthquakes. However, how and when segmentation affects fault behavior and energy release is the basis of many outstanding questions related to the physics of faulting and seismic hazard. These include the probability for a single earthquake to rupture multiple fault segments and the effects of segmentation on earthquake magnitude, radiated seismic energy, and ground motions. Using numerical models, we quantify components of the earthquake energy budget, including the tectonic work acting externally on the system, the energy of internal rock strain, the energy required to overcome fault strength and initiate slip, the energy required to overcome frictional resistance during slip, and the radiated seismic energy. We compare the energy budgets of systems of two en echelon fault segments with various spacing that include both releasing and restraining steps. First, we allow the fault segments to fail simultaneously and capture the effects of segmentation geometry on the earthquake energy budget and on the efficiency with which applied displacement is accommodated. Assuming that higher efficiency correlates with higher probability for a single, larger earthquake, this approach has utility for assessing the seismic hazard of segmented faults. Second, we nucleate slip along a weak portion of one fault segment and let the quasi-static rupture propagate across the system. Allowing fractures to form near faults in these models shows that damage develops within releasing steps and promotes slip along the second fault, while damage develops outside of restraining steps and can prohibit slip along the second fault. Work is consumed in both the propagation of and frictional slip along these new fractures, impacting the energy available

Structure of the la VELA Offshore Basin, Western Venezuela: AN Obliquely-Opening Rift Basin Within the South America-Caribbean Strike-Slip Plate Boundary

Science.gov (United States)

Blanco, J. M.; Mann, P.

2015-12-01

Bathymetric, gravity and magnetic maps show that the east-west trend of the Cretaceous Great Arc of the Caribbean in the Leeward Antilles islands is transected by an en echelon series of obliquely-sheared rift basins that show right-lateral offsets ranging from 20 to 40 km. The basins are 75-100 km in length and 20-30 km in width and are composed of sub-parallel, oblique slip normal faults that define deep, bathymetric channels that bound the larger islands of the Leeward Antilles including Aruba, Curacao and Bonaire. A single basin of similar orientation and structure, the Urumaco basin, is present to the southwest in the Gulf of Venezuela. We mapped structures and sedimentation in the La Vela rift basin using a 3D seismic data volume recorded down to 6 seconds TWT. The basin can be mapped from the Falcon coast where it is correlative with the right-lateral Adicora fault mapped onshore, and its submarine extension. To the southeast of the 3D survey area, previous workers have mapped a 70-km-wide zone of northeast-striking, oblique, right-lateral faults, some with apparent right-lateral offsets of the coastline. On seismic data, the faults vary in dip from 45 to 60 degrees and exhibit maximum vertical offsets of 600 m. The La Vela and other obliquely-opening rifts accommodate right-lateral shear with linkages to intervening, east-west-striking right-lateral faults like the Adicora. The zone of oblique rifts is restricted to the trend of the Great Arc of the Caribbean and may reflect the susceptiblity of this granitic basement to active shearing. The age of onset for the basins known from previous studies on the Leeward Antilles is early Miocene. As most of these faults occur offshore their potential to generate damaging earthquakes in the densely populated Leeward Antilles is not known.

The balancing act between the constitutional right to strike and the constitutional right to education

Directory of Open Access Journals (Sweden)

H J (Jaco Deacon

2014-06-01

Full Text Available While the South African Constitution enshrines both children's right to a basic education and teachers' right to strike, conflict between these two often occurs when the way in which teachers' unions conduct strike actions detracts from learners' education. This article identifies the parties affected by industrial action in the school context, and then proceeds to examine educators' right to strike as defined by the provisions of the Labour Relations Act. The unique implications of picketing in the education environment are then discussed, covering relevant questions such as where pickets may be held, the issue of picketing rules as well as unprotected pickets. Even though we are faced with a qualified right to strike as opposed to an unqualified right to education, the South African reality seems to be that striking teachers are handled with kid gloves. It is therefore concluded that the vast range of existing laws regulating protest action should be applied more effectively. One of the most important aspects should be the picketing rules, which should clearly determine whether picketing in fact contributes to resolution of the dispute, and how learners' interests and rights may best be actualised.

Source study of the Jan Mayen transform fault strike-slip earthquakes

Science.gov (United States)

Rodríguez-Pérez, Q.; Ottemöller, L.

2014-07-01

Seismic source parameters of oceanic transform zone earthquakes have been relatively poorly studied. Previous studies showed that this type of earthquakes has unique characteristics such as not only the relatively common occurrence of slow events with weak seismic radiation at high frequencies but also the occurrence of some events that have high apparent stress indicating strong high frequency radiation. We studied 5 strike-slip earthquakes in the Jan Mayen fracture zone with magnitudes in the range of 5.9 centroid time delay compared to other oceanic transform fault earthquakes.

Using an Earthquake Simulator to Model Tremor Along a Strike Slip Fault

Science.gov (United States)

Cochran, E. S.; Richards-Dinger, K. B.; Kroll, K.; Harrington, R. M.; Dieterich, J. H.

2013-12-01

We employ the earthquake simulator, RSQSim, to investigate the conditions under which tremor occurs in the transition zone of the San Andreas fault. RSQSim is a computationally efficient method that uses rate- and state- dependent friction to simulate a wide range of event sizes for long time histories of slip [Dieterich and Richards-Dinger, 2010; Richards-Dinger and Dieterich, 2012]. RSQSim has been previously used to investigate slow slip events in Cascadia [Colella et al., 2011; 2012]. Earthquakes, tremor, slow slip, and creep occurrence are primarily controlled by the rate and state constants a and b and slip speed. We will report the preliminary results of using RSQSim to vary fault frictional properties in order to better understand rupture dynamics in the transition zone using observed characteristics of tremor along the San Andreas fault. Recent studies of tremor along the San Andreas fault provide information on tremor characteristics including precise locations, peak amplitudes, duration of tremor episodes, and tremor migration. We use these observations to constrain numerical simulations that examine the slip conditions in the transition zone of the San Andreas Fault. Here, we use the earthquake simulator, RSQSim, to conduct multi-event simulations of tremor for a strike slip fault modeled on Cholame section of the San Andreas fault. Tremor was first observed on the San Andreas fault near Cholame, California near the southern edge of the 2004 Parkfield rupture [Nadeau and Dolenc, 2005]. Since then, tremor has been observed across a 150 km section of the San Andreas with depths between 16-28 km and peak amplitudes that vary by a factor of 7 [Shelly and Hardebeck, 2010]. Tremor episodes, comprised of multiple low frequency earthquakes (LFEs), tend to be relatively short, lasting tens of seconds to as long as 1-2 hours [Horstmann et al., in review, 2013]; tremor occurs regularly with some tremor observed almost daily [Shelly and Hardebeck, 2010; Horstmann

The balancing act between the constitutional right to strike and the ...

African Journals Online (AJOL)

While the South African Constitution enshrines both children's right to a basic education and teachers' right to strike, conflict between these two often occurs when the way in which teachers' unions conduct strike actions detracts from learners' education. This article identifies the parties affected by industrial action in the ...

Three-dimensional shuffling of horses in a strike-slip duplex: an example from the Lambertville sill, New Jersey

Science.gov (United States)

Laney, Stephen E.; Gates, Alexander E.

1996-06-01

Detailed analysis of a dextral strike-slip duplex within the relatively isotropic rocks of the Lambertville sill, New Jersey indicates that horses have experienced vertical, horizontal and oblique movements resulting from extrusional shuffling within a restraining bend. This is the first documentation of the three-dimensional movement of horses within a strike-slip duplex. Deformation within the duplex shows a complex system of early synthetic fractures and reverse faults followed by antithetic fractures which dissect previously continuous slab-shaped horses into diamond-shaped lenses. Most faults are oblique slip. Antithetic fault movements and clockwise rigid rotation of horses dominate the south half of the duplex and synthetic movements and counterclockwise rotations dominate the north half. Slickenline plunges on curved horse-bounding fault surfaces within the duplex range from nearly horizontal to 40° resulting in both lateral movements (middle) to normal movements (tails) on a single horse. Curved slickensides commonly have opposite senses of movement on either side of individual horses indicating relative emergence or submergence. Such a geometry could also result from a group of horses moving in the same oblique direction but at different rates. These complex extrusional-type movements were observed in both cross-sectional and plan views. The net result of the movements is a contraction or flattening of the duplex normal to the bounding faults. The horses shifted to accommodate this flattening as overall displacement was transferred between the bounding faults along curved internal faults.

The 2012 Strike-slip Earthquake Sequence in Black Sea and its Link to the Caucasus Collision Zone

Science.gov (United States)

Tseng, T. L.; Hsu, C. H.; Legendre, C. P.; Jian, P. R.; Huang, B. S.; Karakhanian, A.; Chen, C. W.

2016-12-01

The Black Sea formed as a back-arc basin in Late Cretaceous to Paleogene with lots of extensional features. However, the Black Sea is now tectonically stable and absent of notable earthquakes except for the coastal region. In this study we invert regional waveforms of a new seismic array to constrain the focal mechanisms and depths of the 2012/12/23 earthquake sequence occurred in northeastern Black Sea basin that can provide unique estimates on the stress field in the region. The results show that the focal mechanisms for the main shock and 5 larger aftershocks are all strike-slip faulting and resembling with each other. The main rupture fall along the vertical dipping, NW-SE trending sinistral fault indicated by the lineation of most aftershocks. The fault strike and aftershock distribution are both consistent with the Shatsky Ridge, which is continental in nature but large normal faults was created by previous subsidence. The occurrence of 2012 earthquakes can be re-activated, as strike-slip, on one of the pre-existing normal fault cutting at depth nearly 20-30 km in the extended crust. Some of the aftershocks, including a larger one occurred 5 days later, are distributed toward NE direction 20 km away from main fault zone. Those events might be triggered by the main shock along a conjugate fault, which is surprisingly at the extension of proposed transform fault perpendicular to the rift axis of eastern Black Sea Basin. The focal mechanisms also indicate that the maximum compression in northeast Black Sea is at E-W direction, completely different from the N-S compression in the Caucasus and East Turkey controlled by Arabia-Eurasia collision. The origin of E-W maximum compression is probably the same as the secondary stress inferred from earthquakes in Racha region of the Greater Caucasus.

The 2015 M7.2 Sarez, Central Pamir, Earthquake And The Importance Of Strike-Slip Faulting In The Pamir Interior: Insights From Geodesy And Field Observations

Science.gov (United States)

Metzger, Sabrina; Schurr, Bernd; Ratschbacher, Lothar; Schöne, Tilo; Kufner, Sofia-Katerina; Zhang, Yong; Sudhaus, Henriette

2017-04-01

The Pamir mountain range, located in the Northwest of the India-Asia collision zone, accommodates approximately one third of the northward advance of the Indian continent at this longitude (i. e. ˜34 mm/yr) mostly by shortening at its northern thrust system. Geodetic and seismic data sets reveal here a narrow zone of high deformation and M7+ earthquakes of mostly thrust type with some dextral strike-slip faulting observed, too. The Pamir interior shows sinistral strike-slip and normal faulting indicating north-south compression and east-west extension. In this tectonic setting the two largest instrumentally recorded earthquakes, the M7+ 1911 and 2015 earthquake events in the central Pamir occurred with left-lateral shear along a NE-SW rupture plane. We present the co-seismic deformation field of the 2015 earthquake observed by radar satellite interferometry (InSAR), SAR amplitude pixel offsets and high-rate Global Positioning System (GPS). The InSAR and pixel offset results suggest a 50+ km long rupture with sinistral fault offsets at the surface of more than 2 m on a yet unmapped fault trace of the Sarez Karakul Fault System (SKFS). A distributed slip model with a data-driven slip patch resolution yields a sub-vertical fault plane with a strike of N39.5 degrees and a rupture area of ˜80 x 40 km with a maximum slip of 2 m in the upper 10 km of the crust near the surface rupture. Field observations collected some nine months after the earthquake confirm the rupture mechanism, surface trace location and fault offset measurements as constrained by geodetic data. Diffuse deformation was observed across a 1-2 km wide zone, hosting primary fractures sub-parallel to the rupture strike with offsets of 2 m and secondary, en echelon fractures including Riedel shears and hybrid fractures often related to gravitational mass movements. The 1911 and 2015 earthquakes demonstrate the importance of sinistral strike-slip faulting on the SKFS, contributing both to shear between the

A note on 2-D lithospheric deformation due to a blind strike-slip fault

Indian Academy of Sciences (India)

Analytical solution for the problem of a surface-breaking long strike-slip fault in an elastic layer overlying an elastic half-space is well known. The purpose of this note is to obtain the corresponding solution for a blind fault. Since the solution is valid for arbitrary values of the fault-depth and the dip angle, the effects of these ...

Evidence of extensional and strike-slip deformation in the offshore Gökova-Kos area affected by the July 2017 Mw6.6 Bodrum-Kos earthquake, eastern Aegean Sea

Science.gov (United States)

Ocakoğlu, Neslihan; Nomikou, Paraskevi; İşcan, Yeliz; Loreto, Maria Filomena; Lampridou, Danai

2018-01-01

The interpretation of new multichannel seismic profiles and previously published high-resolution swath and seismic reflection data from the Gökova Gulf and southeast of Kos Island in the eastern Aegean Sea revealed new morphotectonic features related to the July 20, 2017 Mw6.6 Bodrum-Kos earthquake offshore between Kos Island and the Bodrum Peninsula. The seafloor morphology in the northern part of the gulf is characterized by south-dipping E-W-oriented listric normal faults. These faults bend to a ENE-WSW direction towards Kos Island, and then extend parallel to the southern coastline. A left-lateral SW-NE strike-slip fault zone is mapped with segments crossing the Gökova Gulf from its northern part to south of Kos Island. This fault zone intersects and displaces the deep basins in the gulf. The basins are thus interpreted as the youngest deformed features in the study area. The strike-slip faults also produce E-W-oriented ridges between the basin segments, and the ridge-related vertical faults are interpreted as reverse faults. This offshore study reveals that the normal and strike-slip faults are well correlated with the focal mechanism solutions of the recent earthquake and general seismicity of the Gökova Gulf. Although the complex morphotectonic features could suggest that the area is under a transtensional regime, kinematic elements normally associated with a transtensional system are missing. At present, the Gökova Gulf is experiencing strike-slip motion with dominant extensional deformation, rather than transtensional deformation.

Evidence of extensional and strike-slip deformation in the offshore Gökova-Kos area affected by the July 2017 Mw6.6 Bodrum-Kos earthquake, eastern Aegean Sea

Science.gov (United States)

Ocakoğlu, Neslihan; Nomikou, Paraskevi; İşcan, Yeliz; Loreto, Maria Filomena; Lampridou, Danai

2018-06-01

The interpretation of new multichannel seismic profiles and previously published high-resolution swath and seismic reflection data from the Gökova Gulf and southeast of Kos Island in the eastern Aegean Sea revealed new morphotectonic features related to the July 20, 2017 Mw6.6 Bodrum-Kos earthquake offshore between Kos Island and the Bodrum Peninsula. The seafloor morphology in the northern part of the gulf is characterized by south-dipping E-W-oriented listric normal faults. These faults bend to a ENE-WSW direction towards Kos Island, and then extend parallel to the southern coastline. A left-lateral SW-NE strike-slip fault zone is mapped with segments crossing the Gökova Gulf from its northern part to south of Kos Island. This fault zone intersects and displaces the deep basins in the gulf. The basins are thus interpreted as the youngest deformed features in the study area. The strike-slip faults also produce E-W-oriented ridges between the basin segments, and the ridge-related vertical faults are interpreted as reverse faults. This offshore study reveals that the normal and strike-slip faults are well correlated with the focal mechanism solutions of the recent earthquake and general seismicity of the Gökova Gulf. Although the complex morphotectonic features could suggest that the area is under a transtensional regime, kinematic elements normally associated with a transtensional system are missing. At present, the Gökova Gulf is experiencing strike-slip motion with dominant extensional deformation, rather than transtensional deformation.

The geometry of the active strike-slip El Tigre Fault, Precordillera of San Juan, Central-Western Argentina: integrating resistivity surveys with structural and geomorphological data

Science.gov (United States)

Fazzito, Sabrina Y.; Cortés, José M.; Rapalini, Augusto E.; Terrizzano, Carla M.

2013-07-01

The geometry and related geomorphological features of the right-lateral strike-slip El Tigre Fault, one of the main morphostructural discontinuities in the Central-Western Precordillera of Argentina, were investigated. Achievements of this survey include: recognition of structural and geometrical discontinuities along the fault trace, identification and classification of landforms associated with local transpressional and transtensional sectors, observation of significant changes in the fault strike and detection of right and left bends of different wavelength. In the Central Segment of the El Tigre Fault, 2D electrical resistivity tomography surveys were carried out across the fault zone. The resistivity imaging permitted to infer the orientation of the main fault surface, the presence of blind fault branches along the fault zone, tectonic tilting of the Quaternary sedimentary cover, subsurface structure of pressure ridges and depth to the water table. Based on this information, it is possible to characterize the El Tigre Fault also as an important hydro-geological barrier. Our survey shows that the main fault surface changes along different segments from a high-angle to a subvertical setting whilst the vertical-slip component is either reverse or normal, depending on the local transpressive or transtensive regime induced by major bends along the trace. These local variations are expressed as sections of a few kilometres in length with relatively homogeneous behaviour and frequently separated by oblique or transversal structures.

Holocene paleoearthquakes on the strike-slip Porters Pass Fault, Canterbury, New Zealand

International Nuclear Information System (INIS)

Howard, M.; Nicol, A.; Campbell, J.; Pettinga, J.R.

2005-01-01

The Porters Pass Fault comprises a series of discontinuous Holocene active traces which extend for c. 40 km between the Rakaia and Waimakariri Rivers in the foothills of the Southern Alps. There have been no historical earthquakes on the Porters Pass Fault (i.e., within the last 150 yr), and the purpose of this paper is to establish the timing and magnitudes of displacements on the fault at the ground surface during Holocene paleoearthquakes. Displaced geomorphic features (e.g., relict streams, stream channels, and ridge crests), measured using either tape measure (n = 20) or surveying equipment (n = 5), range from 5.5 to 33 m right lateral strike slip and are consistent with six earthquakes characterised by slip per event of c. 5-7 m. The timing of these earthquakes is constrained by radiocarbon dates from four trenches excavated across the fault and two auger sites from within swamps produced by ponding of drainage along the fault scarp. These data indicate markedly different Holocene earthquake histories along the fault length separated by a behavioural segment boundary near Lake Coleridge. On the eastern segment at least six Holocene earthquakes were identified at 8400-9000, 5700-6700, 4500-6000, 2300-2500, 800-1100, and 500-600 yr BP, producing an average recurrence interval of c. 1500 yr. On the western segment of the fault in the Rakaia River valley, a single surface-rupturing earthquake displaced Acheron Advance glacial deposits (c.10,000-14,000 yr in age) and may represent the southward continuation of the 2300-2500 yr event identified on the eastern segment. These data suggest Holocene slip rates of 3.2-4.1 mm/yr and 0.3-0.9 mm/yr on the eastern and western sections of the fault, respectively. Displacement and timing data suggest that earthquakes ruptured the western segment of the fault in no more than one-sixth of cases and that for a sample period of 10,000 yr the recurrence intervals were not characteristic. (auth). 45 refs., 10 figs., 3 tabs

Structure of the Melajo clay near Arima, Trinidad and strike-slip motion in the El Pilar fault zone

Science.gov (United States)

Robertson, P.; Burke, K.; Wadge, G.

1985-01-01

No consensus has yet emerged on the sense, timing and amount of motion in the El Pilar fault zone. As a contribution to the study of this problem, a critical area within the zone in North Central Trinidad has been mapped. On the basis of the mapping, it is concluded that the El Pilar zone has been active in right-lateral strike-slip motion during the Pleistocene. Recognition of structural styles akin to those of the mapped area leads to the suggestion that the El Pilar zone is part of a 300 km wide plate boundary zone extending from the Orinoco delta northward to Grenada. Lateral motion of the Caribbean plate with respect to South America has been suggested to amount to 1900 km in the last 38 Ma. Part of this displacement since the Miocene can be readily accommodated within the broad zone identified here. No one fault system need account for more than a fraction of the total motion and all faults need not be active simultaneously.

The rupture process of the Manjil, Iran earthquake of 20 june 1990 and implications for intraplate strike-slip earthquakes

Science.gov (United States)

Choy, G.L.; Zednik, J.

1997-01-01

In terms of seismically radiated energy or moment release, the earthquake of 20 January 1990 in the Manjil Basin-Alborz Mountain region of Iran is the second largest strike-slip earthquake to have occurred in an intracontinental setting in the past decade. It caused enormous loss of life and the virtual destruction of several cities. Despite a very large meizoseismal area, the identification of the causative faults has been hampered by the lack of reliable earthquake locations and conflicting field reports of surface displacement. Using broadband data from global networks of digitally recording seismographs, we analyse broadband seismic waveforms to derive characteristics of the rupture process. Complexities in waveforms generated by the earthquake indicate that the main shock consisted of a tiny precursory subevent followed in the next 20 seconds by a series of four major subevents with depths ranging from 10 to 15 km. The focal mechanisms of the major subevents, which are predominantly strike-slip, have a common nodal plane striking about 285??-295??. Based on the coincidence of this strike with the dominant tectonic fabric of the region we presume that the EW striking planes are the fault planes. The first major subevent nucleated slightly south of the initial precursor. The second subevent occurred northwest of the initial precursor. The last two subevents moved progressively southeastward of the first subevent in a direction collinear with the predominant strike of the fault planes. The offsets in the relative locations and the temporal delays of the rupture subevents indicate heterogeneous distribution of fracture strength and the involvement of multiple faults. The spatial distribution of teleseismic aftershocks, which at first appears uncorrelated with meizoseismal contours, can be decomposed into stages. The initial activity, being within and on the periphery of the rupture zone, correlates in shape and length with meizoseismal lines. In the second stage

The initiation and linkage of surface fractures above a buried strike ...

Indian Academy of Sciences (India)

a buried strike-slip fault: An experimental approach. N Ghosh and A ... conditions viz., (i) heterogeneous simple shear of the cover rocks above a buried strike slip fault. (wrench .... (iii) study of fracture types in the damage zones from Gozo .... was dominant, the results may vary from a true ... For example, as shown in figure 5 ...

The Damage and Geochemical Signature of a Crustal Scale Strike-Slip Fault Zone

Science.gov (United States)

Gomila, R.; Mitchell, T. M.; Arancibia, G.; Jensen Siles, E.; Rempe, M.; Cembrano, J. M.; Faulkner, D. R.

2013-12-01

Fluid-flow migration in the upper crust is strongly controlled by fracture network permeability and connectivity within fault zones, which can lead to fluid-rock chemical interaction represented as mineral precipitation in mesh veins and/or mineralogical changes (alteration) of the host rock. While the dimensions of fault damage zones defined by fracture intensity is beginning to be better understood, how such dimensions compare to the size of alteration zones is less well known. Here, we show quantitative structural and chemical analyses as a function of distance from a crustal-scale strike-slip fault in the Atacama Fault System, Northern Chile, to compare fault damage zone characteristics with its geochemical signature. The Jorgillo Fault (JF) is a ca. 18 km long NNW striking strike-slip fault cutting Mesozoic rocks with sinistral displacement of ca. 4 km. In the study area, the JF cuts through orthogranulitic and gabbroic rocks at the west (JFW) and the east side (JFE), respectively. A 200 m fault perpendicular transect was mapped and sampled for structural and XRF analyses of the core, damage zone and protolith. The core zone consists of a ca. 1 m wide cataclasite zone bounded by two fault gouge zones ca. 40 cm. The damage zone width defined by fracture density is ca. 50 m wide each side of the core. The damage zone in JFW is characterized by NW-striking subvertical 2 cm wide cataclastic rocks and NE-striking milimetric open fractures. In JFE, 1-20 mm wide chlorite, quartz-epidote and quartz-calcite veins, cut the gabbro. Microfracture analysis in JFW reveal mm-wide cataclasitic/ultracataclasitic bands with clasts of protolith and chlorite orientated subparallel to the JF in the matrix, calcite veins in a T-fractures orientation, and minor polidirectional chlorite veins. In JFE, chlorite filled conjugate fractures with syntaxial growth textures and evidence for dilational fracturing processes are seen. Closest to the core, calcite veins crosscut chlorite veins

Structural analysis of S-wave seismics around an urban sinkhole: evidence of enhanced dissolution in a strike-slip fault zone

Science.gov (United States)

Wadas, Sonja H.; Tanner, David C.; Polom, Ulrich; Krawczyk, Charlotte M.

2017-12-01

In November 2010, a large sinkhole opened up in the urban area of Schmalkalden, Germany. To determine the key factors which benefited the development of this collapse structure and therefore the dissolution, we carried out several shear-wave reflection-seismic profiles around the sinkhole. In the seismic sections we see evidence of the Mesozoic tectonic movement in the form of a NW-SE striking, dextral strike-slip fault, known as the Heßleser Fault, which faulted and fractured the subsurface below the town. The strike-slip faulting created a zone of small blocks ( sinkholes and dissolution-induced depressions. Since the processes are still ongoing, the occurrence of a new sinkhole cannot be ruled out. This case study demonstrates how S-wave seismics can characterize a sinkhole and, together with geological information, can be used to study the processes that result in sinkhole formation, such as a near-surface fault zone located in soluble rocks. The more complex the fault geometry and interaction between faults, the more prone an area is to sinkhole occurrence.

The San Andreas Fault and a Strike-slip Fault on Europa

Science.gov (United States)

1998-01-01

The mosaic on the right of the south polar region of Jupiter's moon Europa shows the northern 290 kilometers (180 miles) of a strike-slip fault named Astypalaea Linea. The entire fault is about 810 kilometers (500 miles) long, the size of the California portion of the San Andreas fault on Earth which runs from the California-Mexico border north to the San Francisco Bay. The left mosaic shows the portion of the San Andreas fault near California's san Francisco Bay that has been scaled to the same size and resolution as the Europa image. Each covers an area approximately 170 by 193 kilometers(105 by 120 miles). The red line marks the once active central crack of the Europan fault (right) and the line of the San Andreas fault (left). A strike-slip fault is one in which two crustal blocks move horizontally past one another, similar to two opposing lanes of traffic. The overall motion along the Europan fault seems to have followed a continuous narrow crack along the entire length of the feature, with a path resembling stepson a staircase crossing zones which have been pulled apart. The images show that about 50 kilometers (30 miles) of displacement have taken place along the fault. Opposite sides of the fault can be reconstructed like a puzzle, matching the shape of the sides as well as older individual cracks and ridges that had been broken by its movements. Bends in the Europan fault have allowed the surface to be pulled apart. This pulling-apart along the fault's bends created openings through which warmer, softer ice from below Europa's brittle ice shell surface, or frozen water from a possible subsurface ocean, could reach the surface. This upwelling of material formed large areas of new ice within the boundaries of the original fault. A similar pulling apart phenomenon can be observed in the geological trough surrounding California's Salton Sea, and in Death Valley and the Dead Sea. In those cases, the pulled apart regions can include upwelled materials, but may

The Right to strike: International and regional legal instruments with accent of legislation in Republic of Macedonia

OpenAIRE

Majhosev, Andon; Denkova, Jadranka

2013-01-01

The right to strike is a universal democratic right of all employees, regardless of where they are employed: Real or public sector. Depending on the degree of realization of this right in a state, it is accordingly evaluated on the scale of democracy. Therefore, we can say that the right to strike is a fundamental measure of democratic values of a society. There is no real democracy without the right to strike. The right to strike is governed by international legal instruments (acts) of the U...

The role of the East Asian active margin in widespread extensional and strike-slip deformation in East Asia

NARCIS (Netherlands)

Schellart, Wouter P.; Lister, G. S.

2005-01-01

East Asia is a region of widespread deformation, dominated by normal and strike-slip faults. Deformation has been interpreted to result from extrusion tectonics related to the India-Eurasia collision, which started in the Early Eocene. In East and SE China, however, deformation started earlier than

Oblique strike-slip motion off the Southeastern Continental Margin of India: Implication for the separation of Sri Lanka from India

Science.gov (United States)

Desa, Maria Ana; Ismaiel, Mohammad; Suresh, Yenne; Krishna, Kolluru Sree

2018-05-01

The ocean floor in the Bay of Bengal has evolved after the breakup of India from Antarctica since the Early Cretaceous. Recent geophysical investigations including updated satellite derived gravity map postulated two phases for the tectonic evolution of the Bay of Bengal, the first phase of spreading occurred in the NW-SE direction forming its Western Basin, while the second phase occurred in the N-S direction resulting in its Eastern Basin. Lack of magnetic data along the spreading direction in the Western Basin prompted us to acquire new magnetic data along four tracks (totaling ∼3000 km) to validate the previously identified magnetic anomaly picks. Comparison of the synthetic seafloor spreading model with the observed magnetic anomalies confirmed the presence of Mesozoic anomalies M12n to M0 in the Western Basin. Further, the model suggests that this spreading between India and Antarctica took place with half-spreading rates of 2.7-4.5 cm/yr. The trend of the fracture zones in the Western Basin with respect to that of the Southeastern Continental Margin of India (SCMI) suggests that SCMI is an oblique transform margin with 37° obliquity. Further, the SCMI consists of two oblique transform segments separated by a small rift segment. The strike-slip motion along the SCMI is bounded by the rift segments of the Northeastern Continental Margin of India and the southern margin of Sri Lanka. The margin configuration and fracture zones inferred in its conjugate Western Enderby Basin, East Antarctica helped in inferring three spreading corridors off the SCMI in the Western Basin of the Bay of Bengal. Detailed grid reconstruction models traced the oblique strike-slip motion off the SCMI since M12n time. The strike-slip motion along the short northern transform segment ended by M11n time. The longer transform segment, found east of Sri Lanka lost its obliquity and became a pure oceanic transform fault by M0 time. The eastward propagation of the Africa

A Physical Analog Model of Strike-Slip Faulting for Model-Based Inquiry in the Classroom

Science.gov (United States)

Curren, I. S.; Glesener, G.

2013-12-01

Geoscience educators often use qualitative physical analog models to demonstrate natural processes; while these are effective teaching tools, they often neglect the fundamental scientific practices that make up the core of scientific work. Physical analog models with dynamic properties that can be manipulated and measured quantitatively in real-time, on the other hand, can give students the opportunity to explore, observe and empirically test their own ideas and hypotheses about the relevant target concepts within a classroom setting. Providing classroom content for inquiry, such as a hands-on physical analog model, which fosters students' production and refinement of their mental models in participatory and discursive activities have been argued by many education researchers to help students build a deeper understanding of science and scientific reasoning. We present a physical analog model that was originally developed by UCLA's Modeling and Educational Demonstrations Laboratory (MEDL) for the purpose of engaging students in the study of elastic rebound on a strike-slip fault; it was later modified to accommodate research of complex tectonic processes associated with strike-slip faulting, which are currently debated by scientists in both the geology and geophysics disciplines. During experimentation, it became clear that this new design could be used as a relevant resource for inquiry from which students would be able to make and discuss real-time empirical measurements and observations to help them infer causal accounts of theoretical and/or unobservable dynamic processes within the Earth's crust. In our poster session, we will: 1) demonstrate the physical analog model; 2) describe various real-time data collection tools, as well as quantitative methods students can use to process their data; and 3) describe the surficial, structural and relational similarities between the physical analog model and the target concepts intended for students to explore in the

The Trans-Rocky Mountain Fault System - A Fundamental Precambrian Strike-Slip System

Science.gov (United States)

Sims, P.K.

2009-01-01

Recognition of a major Precambrian continental-scale, two-stage conjugate strike-slip fault system - here designated as the Trans-Rocky Mountain fault system - provides new insights into the architecture of the North American continent. The fault system consists chiefly of steep linear to curvilinear, en echelon, braided and branching ductile-brittle shears and faults, and local coeval en echelon folds of northwest strike, that cut indiscriminately across both Proterozoic and Archean cratonic elements. The fault system formed during late stages of two distinct tectonic episodes: Neoarchean and Paleoproterozoic orogenies at about 2.70 and 1.70 billion years (Ga). In the Archean Superior province, the fault system formed (about 2.70-2.65 Ga) during a late stage of the main deformation that involved oblique shortening (dextral transpression) across the region and progressed from crystal-plastic to ductile-brittle deformation. In Paleoproterozoic terranes, the fault system formed about 1.70 Ga, shortly following amalgamation of Paleoproterozoic and Archean terranes and the main Paleoproterozoic plastic-fabric-producing events in the protocontinent, chiefly during sinistral transpression. The postulated driving force for the fault system is subcontinental mantle deformation, the bottom-driven deformation of previous investigators. This model, based on seismic anisotropy, invokes mechanical coupling and subsequent shear between the lithosphere and the asthenosphere such that a major driving force for plate motion is deep-mantle flow.

Strikes in Serbia since 2000 to 2005

OpenAIRE

Novaković Nada

2005-01-01

In this article author deals with main characteristics of strikes in Serbia within the period 2000–2005. Analysis starts with thesis that strike is open class conflict within class divided society. Therefore strike is radical form of trade union struggle for workers rights. Main questions in the analysis were: on social structure as a background of strikes, on organizations and trade unions included in it, on effects of strikes in Serbia in the given period. Main thesis of the article is that...

The balancing act between the constitutional right to strike and the ...

African Journals Online (AJOL)

(a) a service the interruption of which endangers the life, personal safety or health of the whole or ... companies act through organs such as the board of directors. ... Once a right to strike is recognised, an application for the right to picket must.

Palaeopermeability anisotropies of a strike-slip fault damage zone: 3D Insights of quantitative fluid flow from µCT analysis.

Science.gov (United States)

Gomila, R.; Arancibia, G.; Nehler, M.; Bracke, R.; Morata, D.

2017-12-01

Fault zones and their related structural permeability are a key aspect in the migration of fluids through the continental crust. Therefore, the estimation of the hydraulic properties (palaeopermeability conditions; k) and the spatial distribution of the fracture mesh within the damage zone (DZ) are critical in the assessment of fault zones behavior for fluids. The study of the real spatial distribution of the veinlets of the fracture mesh (3D), feasible with the use of µCT analyses, is a first order factor to unravel both, the real structural permeability conditions of a fault-zone, and the validation of previous (and classical) estimations made in 2D analyses in thin-sections. This work shows the results of a fault-related fracture mesh and its 3D spatial distribution in the damage-zone of the Jorgillo Fault (JF), an ancient subvertical left-lateral strike-slip fault exposed in the Atacama Fault System in northern Chile. The JF is a ca. 20 km long NNW-striking strike-slip fault with sinistral displacement of ca. 4 km. The methodology consisted of drilling 5 mm vertically oriented plugs at several locations within the JF damage zone. Each specimen was scanned with an X-Ray µCT scanner, to assess the fracture mesh, with a voxel resolution of ca. 4.5 µm in the 3D reconstructed data. Tensor permeability modeling, using Lattice-Boltzmann Method, through the segmented microfracture mesh show GMkmin (geometric mean values) of 2.1x10-12 and 9.8x10-13 m2, and GMkmax of 6.4x10-12 and 2.1x10-12 m2. A high degree of anisotropy of the DZ permeability tensor both sides of the JF (eastern and western side, respectively) is observed, where the k values in the kmax plane are 2.4 and 1.9 times higher than the kmin direction at the time of fracture sealing. This style of anisotropy is consistent with the obtained for bedded sandstones supporting the idea that damage zones have an analogous effect - but vertically orientated - on bulk permeability (in low porosity rocks) as

Ethical and legal consideration of prisoner's hunger strike in Serbia.

Science.gov (United States)

Alempijevic, Djordje; Pavlekic, Snezana; Jecmenica, Dragan; Nedeljkov, Aleksandra; Jankovic, Milos

2011-03-01

Hunger strike of prisoners and detainees remains a major human rights and ethical issue for medical professionals. We are reporting on a case of a 48-year-old male sentenced prisoner, intravenous heroin user, who went on a hunger strike and died 15 days later. Throughout the fasting period, the prisoner, who was capable of decision making, refused any medical examination. Autopsy findings were not supporting prolonged starvation, while toxicology revealed benzodiazepines and opiates in blood and urine. Cause of death was given as "heroin intoxication" in keeping with detection of 6-MAM. Legal and ethical issues pertinent to medical examination and treatment of prisoners on hunger strike are explored in accordance with legislation and professional ethical standards in Serbia. A recommendation for the best autopsy practice in deaths following hunger strike has been made. © 2011 American Academy of Forensic Sciences.

The effect of hand dominance on martial arts strikes.

Science.gov (United States)

Neto, Osmar Pinto; Silva, Jansen Henrique; Marzullo, Ana Carolina de Miranda; Bolander, Richard P; Bir, Cynthia A

2012-08-01

The main goal of this study was to compare dominant and non-dominant martial arts palm strikes under different circumstances that usually happen during martial arts and combative sports applications. Seven highly experienced (10±5 years) right hand dominant Kung Fu practitioners performed strikes with both hands, stances with left or right lead legs, and with the possibility or not of stepping towards the target (moving stance). Peak force was greater for the dominant hand strikes (1593.76±703.45 N vs. 1042.28±374.16 N; p<.001), whereas no difference was found in accuracy between the hands (p=.141). Additionally, peak force was greater for the strikes with moving stance (1448.75±686.01 N vs. 1201.80±547.98 N; p=.002) and left lead leg stance (1378.06±705.48 N vs. 1269.96±547.08 N). Furthermore, the difference in peak force between strikes with moving and stationary stances was statistically significant only for the strikes performed with a left lead leg stance (p=.007). Hand speed was higher for the dominant hand strikes (5.82±1.08 m/s vs. 5.24±0.78 m/s; p=.001) and for the strikes with moving stance (5.79±1.01 m/s vs. 5.29±0.90 m/s; p<.001). The difference in hand speed between right and left hand strikes was only significant for strikes with moving stance. In summary, our results suggest that the stronger palm strike for a right-handed practitioner is a right hand strike on a left lead leg stance moving towards the target. Copyright © 2011 Elsevier B.V. All rights reserved.

Striking Clepsydras

Science.gov (United States)

Nam, Moon-Hyon

The term "Striking Clepsydra" is a shortened translation of the Korean name Jagyeongnu (自擊漏, tzu-chi lou in Chinese, literally "automatic-striking water-clock"). It was given to the two monumental time-keeping installations built by chief court engineer Yeong-sil Jang in AD 1432-38 under King Sejong (r. AD 1418-50) of the Joseon dynasty (1392-1910) in Seoul. These were housed separately in the Gyeongbok palace complex as major installations of the Royal Observatory Ganuidae equipped during 1432-38. One was the Striking Palace Clepsydra Borugangnu that was employed as the standard time-keeper from 1434, and the other was the Striking Heavenly Clepsydra Heumgyeonggangnu that was put into use not only as the symbol of Neo-Confucian ideology from 1438, but also as a demonstrational orrery and time-keeper. These were restored several times through the dynasty after loss by fires and warfare, and clepsydra-making technologies were succeeded by the development of armillary clocks in 1669. The National Palace Museum of Korea recreated the 1434 Striking Palace Clepsydra of King Sejong, and the replica was installed for permanent exhibition from November 2007.

Lightning Often Strikes Twice

Science.gov (United States)

2005-01-01

Contrary to popular misconception, lightning often strikes the same place twice. Certain conditions are just ripe for a bolt of electricity to come zapping down; and a lightning strike is powerful enough to do a lot of damage wherever it hits. NASA created the Accurate Location of Lightning Strikes technology to determine the ground strike point of lightning and prevent electrical damage in the immediate vicinity of the Space Shuttle launch pads at Kennedy Space Center. The area surrounding the launch pads is enmeshed in a network of electrical wires and components, and electronic equipment is highly susceptible to lightning strike damage. The accurate knowledge of the striking point is important so that crews can determine which equipment or system needs to be retested following a strike. Accurate to within a few yards, this technology can locate a lightning strike in the perimeter of the launch pad. As an added bonus, the engineers, then knowing where the lightning struck, can adjust the variables that may be attracting the lightning, to create a zone that will be less susceptible to future strikes.

The Evolution from Late Miocene West Salton Detachment Faulting to Cross-Cutting Pleistocene Oblique Strike-Slip Faults in the SW Salton Trough, Southern California

OpenAIRE

Steely, Alexander N.

2006-01-01

Field studies in the southwest Salton Trough between Yaqui Ridge and Borrego Mountain show that the West Salton detachment fault was active during the Pliocene and may have initiated during the latest Miocene. At Yaqui Ridge dominantly east-directed extension is recorded by slickenlines on the NW-striking detachment fault, and shows that the fault is actually a low-angle dextral oblique strike-slip fault. Crustal inheritance is responsible for the position of the fault at Yaqui Ridge, which r...

Stress distribution of metatarsals during forefoot strike versus rearfoot strike: A finite element study.

Science.gov (United States)

Li, Shudong; Zhang, Yan; Gu, Yaodong; Ren, James

2017-12-01

Due to the limitations of experimental approaches, comparison of the internal deformation and stresses of the human man foot between forefoot and rearfoot landing is not fully established. The objective of this work is to develop an effective FE modelling approach to comparatively study the stresses and energy in the foot during forefoot strike (FS) and rearfoot strike (RS). The stress level and rate of stress increase in the Metatarsals are established and the injury risk between these two landing styles is evaluated and discussed. A detailed subject specific FE foot model is developed and validated. A hexahedral dominated meshing scheme was applied on the surface of the foot bones and skin. An explicit solver (Abaqus/Explicit) was used to stimulate the transient landing process. The deformation and internal energy of the foot and stresses in the metatarsals are comparatively investigated. The results for forefoot strike tests showed an overall higher average stress level in the metatarsals during the entire landing cycle than that for rearfoot strike. The increase rate of the metatarsal stress from the 0.5 body weight (BW) to 2 BW load point is 30.76% for forefoot strike and 21.39% for rearfoot strike. The maximum rate of stress increase among the five metatarsals is observed on the 1st metatarsal in both landing modes. The results indicate that high stress level during forefoot landing phase may increase potential of metatarsal injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analogue Modeling of Oblique Convergent Strike-Slip Faulting and Application to The Seram Island, Eastern Indonesia

Directory of Open Access Journals (Sweden)

Benyamin Sapiie

2014-12-01

Full Text Available DOI:10.17014/ijog.v1i3.189Sandbox experiment is one of the types of analogue modeling in geological sciences in which the main purpose is simulating deformation style and structural evolution of the sedimentary basin.  Sandbox modeling is one of the effective ways in conducting physically modeling and evaluates complex deformation of sedimentary rocks. The main purpose of this paper is to evaluate structural geometry and deformation history of oblique convergent deformation using of integrated technique of analogue sandbox modeling applying to deformation of Seram Fold-Thrust-Belt (SFTB in the Seram Island, Eastern Indonesia. Oblique convergent strike-slip deformation has notoriously generated area with structural complex geometry and pattern resulted from role of various local parameters that control stress distributions. Therefore, a special technique is needed for understanding and solving such problem in particular to relate 3D fault geometry and its evolution. The result of four case (Case 1 to 4 modeling setting indicated that two of modeling variables clearly affected in our sandbox modeling results; these are lithological variation (mainly stratigraphy of Seram Island and pre-existing basement fault geometry (basement configuration. Lithological variation was mainly affected in the total number of faults development.  On the other hand, pre-existing basement fault geometry was highly influenced in the end results particularly fault style and pattern as demonstrated in Case 4 modeling.  In addition, this study concluded that deformation in the Seram Island is clearly best described using oblique convergent strike-slip (transpression stress system.

Structural analysis of S-wave seismics around an urban sinkhole: evidence of enhanced dissolution in a strike-slip fault zone

Directory of Open Access Journals (Sweden)

S. H. Wadas

2017-12-01

Full Text Available In November 2010, a large sinkhole opened up in the urban area of Schmalkalden, Germany. To determine the key factors which benefited the development of this collapse structure and therefore the dissolution, we carried out several shear-wave reflection-seismic profiles around the sinkhole. In the seismic sections we see evidence of the Mesozoic tectonic movement in the form of a NW–SE striking, dextral strike-slip fault, known as the Heßleser Fault, which faulted and fractured the subsurface below the town. The strike-slip faulting created a zone of small blocks ( < 100 m in size, around which steep-dipping normal faults, reverse faults and a dense fracture network serve as fluid pathways for the artesian-confined groundwater. The faults also acted as barriers for horizontal groundwater flow perpendicular to the fault planes. Instead groundwater flows along the faults which serve as conduits and forms cavities in the Permian deposits below ca. 60 m depth. Mass movements and the resulting cavities lead to the formation of sinkholes and dissolution-induced depressions. Since the processes are still ongoing, the occurrence of a new sinkhole cannot be ruled out. This case study demonstrates how S-wave seismics can characterize a sinkhole and, together with geological information, can be used to study the processes that result in sinkhole formation, such as a near-surface fault zone located in soluble rocks. The more complex the fault geometry and interaction between faults, the more prone an area is to sinkhole occurrence.

'Extra-regional' strike-slip fault systems in Chile and Alaska: the North Pacific Rim orogenic Stream vs. Beck's Buttress

Science.gov (United States)

Redfield, T. F.; Scholl, D. W.; Fitzgerald, P. G.

2010-12-01

The ~2000 km long Denali Fault System (DFS) of Alaska is an example of an extra-regional strike-slip fault system that terminates in a zone of widely-distributed deformation. The ~1200 km long Liquiñe-Ofqui Fault Zone (LOFZ) of Patagonia (southern Chile) is another. Both systems are active, having undergone large-magnitude seismic rupture is 2002 (DFS) and 2007 (LOFZ). Both systems appear to be long-lived: the DFS juxtaposes terranes that docked in at least early Tertiary time, whilst the central LOFZ appears to also record early Tertiary or Mesozoic deformation. Both fault systems comprise a relatively well-defined central zone where individual fault traces can be identified from topographic features or zones of deformed rock. In both cases the proximal and distal traces are much more diffuse tributary and distributary systems of individual, branching fault traces. However, since their inception the DFS and LOFZ have followed very different evolutionary paths. Copious Alaskan paleomagnetic data are consistent with vertical axis small block rotation, long-distance latitudinal translation, and a recently-postulated tectonic extrusion towards a distributary of subordinate faults that branch outward towards the Aleution subduction zone (the North Pacific Rim orogenic Stream; see Redfield et al., 2007). Paleomagnetic data from the LOFZ region are consistent with small block rotation but preclude statistically-significant latitudinal transport. Limited field data from the southernmost LOFZ suggest that high-angle normal and reverse faults dominate over oblique to strike-slip structures. Rather than the high-angle oblique 'slivering regime' of the southeasternmost DFS, the initiation of the LOFZ appears to occur across a 50 to 100 km wide zone of brittly-deformed granitic and gneissic rock characterized by bulk compression and vertical pathways of exhumation. In both cases, relative plate motions are consistent with the hypothetical style, and degree, of offset, leading

Understanding the limitations to the right to strike in essential and ...

African Journals Online (AJOL)

The nature of the limitations to the right to strike in essential and public services in the nine sub-regional countries of Southern Africa – South Africa, Botswana, Lesotho, Namibia, Swaziland, Malawi, Mozambique, Zambia and Zimbabwe – is examined in this contribution. While all of these countries share common influences ...

Preemptive strikes: Fear, hope, and defensive aggression.

Science.gov (United States)

Halevy, Nir

2017-02-01

Preemptive strikes are costly and harmful. Existing models of defensive aggression focus narrowly on the role fear plays in motivating preemptive strikes. Theoretically integrating the literatures on conflict, decision making, and emotion, the current research investigated how specific emotions associated with certainty or uncertainty, including fear, anger, disgust, hope, and happiness, influence preemptive strikes. Study 1 demonstrated that hope negatively predicts defensive exits from relationships in choice dilemmas. Studies 2 and 3 experimentally manipulated risk of being attacked in an incentivized, interactive decision making task-the Preemptive Strike Game. Risk of being attacked fueled preemptive strikes; reduced feelings of hope partially mediated this effect in Study 3. Studies 4 and 5 investigated preemptive strikes under uncertainty (rather than risk). In Study 4, reasoning about the factors that make one trustful of others curbed preemptive strikes; cogitating about the factors that underlie discrete emotions, however, did not influence defensive aggression. Study 5 demonstrated that the valence and uncertainty appraisals of incidental emotions interact in shaping preemptive strikes. Specifically, recalling an autobiographical emotional experience that produced hope significantly decreased attack rates relative to fear, happiness, and a control condition. Fear, anger, disgust, and happiness were either unrelated to preemptive strikes or showed inconsistent relationships with preemptive strikes across the 5 studies. These findings shed light on how emotions shape defensive aggression, advance knowledge on strategic choice under risk and uncertainty, and demonstrate hope's positive effects on social interactions and relationships. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Women, transition and strikes in Serbia

Directory of Open Access Journals (Sweden)

Novaković Nada G.

2014-01-01

Full Text Available The author, in a sociological way, describes and analyzes the concepts of transition, privatization and strikes in Serbia, particularly the place of women in it. It examines the most important economic and social causes and consequences of these phenomena. The main hypothesis is: women's strikes in the Serbian transition are less efficient than strikes and public protests of women in the developed world and the second Yugoslavia. A strike is a class conflict, in which the workers are fighting for their social and economic rights, threatened by the capitalist class. Elites in government and state authorities protect the interests of big capital at the detriment of the interests of the majority of workers. Exploring women's strikes in transition reveals the nature of the social and political system. Their strikes in enterprises, the blocking of public spaces and public protests are systemic, ie. class determined. As the transition was very fast, the resistance of the strikers was inefficient, and the protests of women became an expression of desperation against the loss of jobs and basic resources for lifehood. In short, this research is about the main causes, the organizational forms and the consequences of strikes in which the majority were women. For this purpose, the author chose to describe an array of strikes in the industries and the companies where women are most employed. The choice of strikes in the economic sector is not accidental, but a consequence of the fact that the women there were the most vulnerable. Women in public institutions and companies had much higher financial and social position. They are less likely to strike and publicly protested. After 2000, these strikes were more successful than worker's strikes in textile, food processing, manufacturing and trade. Relationship between the government and the public towards them was tainted by self-interest and selective. The main criterion for the selection of companies and

Analogue modelling of a reactivated, basement controlled strike-slip zone, Sierra de Albarracín, Spain: application of sandbox modelling to polyphase deformation

NARCIS (Netherlands)

Merten, S.; Smit, W.G.; Nieuwland, D.A.; Rondeel, H.E.

2006-01-01

This paper presents the results of an analogue modelling study on the reactivation of Riedel shears generated by basement-induced sinistral strike-slip faulting. It is based on a natural example in the Sierra de Albarracín, Iberian Range (Spain). The area has a polyphase deformation history, defined

(Plio-)Pleistocene alluvial-lacustrine basin infill evolution in a strike-slip active zone (Northern Andes, Western-Central Cordilleras, Colombia)

OpenAIRE

SUTER, F.; NEUWERTH, R.; GORIN, G.; GUZMÁN, C.

2009-01-01

The (Plio)-Pleistocene Zarzal Formation was deposited in the Cauca Depression and Quindío-Risaralda Basin between the Western and Central Cordilleras (Northern Andes). This area is structurally located on the transcurrent Romeral Fault System (RFS). Because of the interaction between the Nazca plate and the Chocó-Panamá block (an active indenter), the RFS strike-slip component changes direction around the study zone (dextral in the south, senestral in the north). Zarzal sediments are the olde...

Analysis of the growth of strike-slip faults using effective medium theory

Energy Technology Data Exchange (ETDEWEB)

Aydin, A.; Berryman, J.G.

2009-10-15

Increases in the dimensions of strike-slip faults including fault length, thickness of fault rock and the surrounding damage zone collectively provide quantitative definition of fault growth and are commonly measured in terms of the maximum fault slip. The field observations indicate that a common mechanism for fault growth in the brittle upper crust is fault lengthening by linkage and coalescence of neighboring fault segments or strands, and fault rock-zone widening into highly fractured inner damage zone via cataclastic deformation. The most important underlying mechanical reason in both cases is prior weakening of the rocks surrounding a fault's core and between neighboring fault segments by faulting-related fractures. In this paper, using field observations together with effective medium models, we analyze the reduction in the effective elastic properties of rock in terms of density of the fault-related brittle fractures and fracture intersection angles controlled primarily by the splay angles. Fracture densities or equivalent fracture spacing values corresponding to the vanishing Young's, shear, and quasi-pure shear moduli were obtained by extrapolation from the calculated range of these parameters. The fracture densities or the equivalent spacing values obtained using this method compare well with the field data measured along scan lines across the faults in the study area. These findings should be helpful for a better understanding of the fracture density/spacing distribution around faults and the transition from discrete fracturing to cataclastic deformation associated with fault growth and the related instabilities.

Long term fault system reorganization of convergent and strike-slip systems

Science.gov (United States)

Cooke, M. L.; McBeck, J.; Hatem, A. E.; Toeneboehn, K.; Beyer, J. L.

2017-12-01

Laboratory and numerical experiments representing deformation over many earthquake cycles demonstrate that fault evolution includes episodes of fault reorganization that optimize work on the fault system. Consequently, the mechanical and kinematic efficiencies of fault systems do not increase monotonically through their evolution. New fault configurations can optimize the external work required to accommodate deformation, suggesting that changes in system efficiency can drive fault reorganization. Laboratory evidence and numerical results show that fault reorganization within accretion, strike-slip and oblique convergent systems is associated with increasing efficiency due to increased fault slip (frictional work and seismic energy) and commensurate decreased off-fault deformation (internal work and work against gravity). Between episodes of fault reorganization, fault systems may become less efficient as they produce increasing off fault deformation. For example, laboratory and numerical experiments show that the interference and interaction between different fault segments may increase local internal work or that increasing convergence can increase work against gravity produced by a fault system. This accumulation of work triggers fault reorganization as stored work provides the energy required to grow new faults that reorganize the system to a more efficient configuration. The results of laboratory and numerical experiments reveal that we should expect crustal fault systems to reorganize following periods of increasing inefficiency, even in the absence of changes to the tectonic regime. In other words, fault reorganization doesn't require a change in tectonic loading. The time frame of fault reorganization depends on fault system configuration, strain rate and processes that relax stresses within the crust. For example, stress relaxation may keep pace with stress accumulation, which would limit the increase in the internal work and gravitational work so that

Understanding the Limitations to the Right to Strike in Essential and Public Services in the SADC Region

Directory of Open Access Journals (Sweden)

Rochelle le Roux

2016-05-01

Full Text Available The nature of the limitations to the right to strike in essential and public services in the nine sub-regional countries of Southern Africa – South Africa, Botswana, Lesotho, Namibia, Swaziland, Malawi, Mozambique, Zambia and Zimbabwe – is examined in this contribution. While all of these countries share common influences and face common challenges, there appears to be a vast disparity in the approaches taken to the right to strike in public and essential services in the region. A brief overview of the demographics and labour markets in the countries under discussion is sketched, the salient features of the ILO's approach to strike in essential and public services is highlighted, and a broad overview of the contrasting and disparate approaches to essential and public services in the region is provided. The focus is, however, on the legislative approach taken to essential service employees in South Africa. It is concluded that – with the exception of South Africa and Namibia – the limitations to the right to strike of public sector employees exceed those endorsed by international conventions, and the broad definition of essential services generally relied upon effectively

Gait Retraining From Rearfoot Strike to Forefoot Strike does not change Running Economy.

Science.gov (United States)

Roper, Jenevieve Lynn; Doerfler, Deborah; Kravitz, Len; Dufek, Janet S; Mermier, Christine

2017-12-01

Gait retraining is a method for management of patellofemoral pain, which is a common ailment among recreational runners. The present study investigated the effects of gait retraining from rearfoot strike to forefoot strike on running economy, heart rate, and respiratory exchange ratio immediately post-retraining and one-month post-retraining in recreational runners with patellofemoral pain. Knee pain was also measured. Sixteen participants (n=16) were randomly placed in the control (n=8) or experimental (n=8) group. A 10-minute treadmill RE test was performed by all subjects. The experimental group performed eight gait retraining running sessions where foot strike pattern was switched from rearfoot strike to forefoot strike, while the control group received no intervention. There were no significant differences for running economy (p=0.26), respiratory exchange ratio (p=0.258), or heart rate (p=0.248) between the groups. Knee pain reported on a visual analog scale was also significantly reduced (pstrike to forefoot strike did not affect running economy up to one-month post-retraining while reducing running-related patellofemoral pain. © Georg Thieme Verlag KG Stuttgart · New York.

3D deformation in strike-slip systems: Analogue modelling and numerical restoration Deformación 3D en sistemas de rumbo: modelación analógica y restauración numérica

Directory of Open Access Journals (Sweden)

Daniel González

2012-05-01

Full Text Available Regional and local strike-slip systems in Chile are complex and pose interesting questions, such as the interaction between strike-slip and reverse faults, how they evolve, and the relationship between shortening, rotation and uplift. Within this context, we developed a new analytical method based on analogue and numerical modelling applied to 3D, pure and transtensional-transpressional strike-slip systems. Analogue modelling results indicate that in restraining stepovers of strike-slip fault systems, where antiformal pop-up structures are usually formed, pre-existent basement structures with a high angle to the main strike-slip fault will generate a higher rotation of blocks. However, when these structures are oriented at a high angle with respect to the main stress convergence vector, the rotation will be less and therefore a higher tendency to uplift will be produced. These results were applied to NW- and SE-striking basement faults oblique to N-S mega-thrust faults in central Chile (32°-35°S, for which we propose a simultaneous development based on the analogue model results. Moreover, we propose that strike-slip movement occurred on thrust faults in central Chile. Furthermore, we performed a numerical restoration of an analogue experiment which modeled a pure strike-slip system, and concluded that the restoration is very sensitive to shortening data as well as to rotational data. These results are extremely important for future numerical and regional analysis of strike-slip systems.Los sistemas de rumbo regionales y locales en Chile son complejos y plantean interesantes preguntas, tales como la interacción entre fallas de rumbo y fallas inversas, cómo evolucionan ellas, y la relación entre acortamiento, rotación y alzamiento. En este contexto, desarrollamos un nuevo método analítico basado en modelamiento analógico y numérico de sistemas de rumbo de cizalle puro y sistemas transpresionales-trantensionales en 3D. Los resultados del

Predicting timing of foot strike during running, independent of striking technique, using principal component analysis of joint angles.

Science.gov (United States)

Osis, Sean T; Hettinga, Blayne A; Leitch, Jessica; Ferber, Reed

2014-08-22

As 3-dimensional (3D) motion-capture for clinical gait analysis continues to evolve, new methods must be developed to improve the detection of gait cycle events based on kinematic data. Recently, the application of principal component analysis (PCA) to gait data has shown promise in detecting important biomechanical features. Therefore, the purpose of this study was to define a new foot strike detection method for a continuum of striking techniques, by applying PCA to joint angle waveforms. In accordance with Newtonian mechanics, it was hypothesized that transient features in the sagittal-plane accelerations of the lower extremity would be linked with the impulsive application of force to the foot at foot strike. Kinematic and kinetic data from treadmill running were selected for 154 subjects, from a database of gait biomechanics. Ankle, knee and hip sagittal plane angular acceleration kinematic curves were chained together to form a row input to a PCA matrix. A linear polynomial was calculated based on PCA scores, and a 10-fold cross-validation was performed to evaluate prediction accuracy against gold-standard foot strike as determined by a 10 N rise in the vertical ground reaction force. Results show 89-94% of all predicted foot strikes were within 4 frames (20 ms) of the gold standard with the largest error being 28 ms. It is concluded that this new foot strike detection is an improvement on existing methods and can be applied regardless of whether the runner exhibits a rearfoot, midfoot, or forefoot strike pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lightning Strike in Pregnancy With Fetal Injury.

Science.gov (United States)

Galster, Kellen; Hodnick, Ryan; Berkeley, Ross P

2016-06-01

Injuries from lightning strikes are an infrequent occurrence, and are only rarely noted to involve pregnant victims. Only 13 cases of lightning strike in pregnancy have been previously described in the medical literature, along with 7 additional cases discovered within news media reports. This case report presents a novel case of lightning-associated injury in a patient in the third trimester of pregnancy, resulting in fetal ischemic brain injury and long-term morbidity, and reviews the mechanics of lightning strikes along with common injury patterns of which emergency providers should be aware. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

"Thunderstruck": penetrating thoracic injury from lightning strike.

Science.gov (United States)

van Waes, Oscar J F; van de Woestijne, Pieter C; Halm, Jens A

2014-04-01

Lightning strike victims are rarely presented at an emergency department. Burns are often the primary focus. This case report describes the improvised explosive device like-injury to the thorax due to lightning strike and its treatment, which has not been described prior in (kerauno)medicine. Penetrating injury due to blast from lightning strike is extremely rare. These "shrapnel" injuries should however be ruled out in all patients struck by lightning. Copyright © 2013 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.

Finite element models of earthquake cycles in mature strike-slip fault zones

Science.gov (United States)

Lynch, John Charles

The research presented in this dissertation is on the subject of strike-slip earthquakes and the stresses that build and release in the Earth's crust during earthquake cycles. Numerical models of these cycles in a layered elastic/viscoelastic crust are produced using the finite element method. A fault that alternately sticks and slips poses a particularly challenging problem for numerical implementation, and a new contact element dubbed the "Velcro" element was developed to address this problem (Appendix A). Additionally, the finite element code used in this study was bench-marked against analytical solutions for some simplified problems (Chapter 2), and the resolving power was tested for the fault region of the models (Appendix B). With the modeling method thus developed, there are two main questions posed. First, in Chapter 3, the effect of a finite-width shear zone is considered. By defining a viscoelastic shear zone beneath a periodically slipping fault, it is found that shear stress concentrates at the edges of the shear zone and thus causes the stress tensor to rotate into non-Andersonian orientations. Several methods are used to examine the stress patterns, including the plunge angles of the principal stresses and a new method that plots the stress tensor in a manner analogous to seismic focal mechanism diagrams. In Chapter 4, a simple San Andreas-like model is constructed, consisting of two great earthquake producing faults separated by a freely-slipping shorter fault. The model inputs of lower crustal viscosity, fault separation distance, and relative breaking strengths are examined for their effect on fault communication. It is found that with a lower crustal viscosity of 1018 Pa s (in the lower range of estimates for California), the two faults tend to synchronize their earthquake cycles, even in the cases where the faults have asymmetric breaking strengths. These models imply that postseismic stress transfer over hundreds of kilometers may play a

Influence of fault steps on rupture termination of strike-slip earthquake faults

Science.gov (United States)

Li, Zhengfang; Zhou, Bengang

2018-03-01

A statistical analysis was completed on the rupture data of 29 historical strike-slip earthquakes across the world. The purpose of this study is to examine the effects of fault steps on the rupture termination of these events. The results show good correlations between the type and length of steps with the seismic rupture and a poor correlation between the step number and seismic rupture. For different magnitude intervals, the smallest widths of the fault steps (Lt) that can terminate the rupture propagation are variable: Lt = 3 km for Ms 6.5 6.9, Lt = 4 km for Ms 7.0 7.5, Lt = 6 km for Ms 7.5 8.0, and Lt = 8 km for Ms 8.0 8.5. The dilational fault step is easier to rupture through than the compression fault step. The smallest widths of the fault step for the rupture arrest can be used as an indicator to judge the scale of the rupture termination of seismic faults. This is helpful for research on fault segmentation, as well as estimating the magnitude of potential earthquakes, and is thus of significance for the assessment of seismic risks.

Evidence for slip partitioning and bimodal slip behavior on a single fault: Surface slip characteristics of the 2013 Mw7.7 Balochistan, Pakistan earthquake

Science.gov (United States)

Barnhart, William; Briggs, Richard; Reitman, Nadine G.; Gold, Ryan D.; Hayes, Gavin

2015-01-01

Deformation is commonly accommodated by strain partitioning on multiple, independent strike-slip and dip-slip faults in continental settings of oblique plate convergence. As a corollary, individual faults tend to exhibit one sense of slip – normal, reverse, or strike-slip – until whole-scale changes in boundary conditions reactivate preexisting faults in a new deformation regime. In this study, we show that a single continental fault may instead partition oblique strain by alternatively slipping in a strike-slip or a dip-slip sense during independent fault slip events. We use 0.5 m resolution optical imagery and sub-pixel correlation analysis of the 200+ km 200+km"> 2013 Mw7.7 Balochistan, Pakistan earthquake to document co-seismic surface slip characteristics and Quaternary tectonic geomorphology along the causative Hoshab fault. We find that the 2013 earthquake, which involved a ∼6:1 strike-slip to dip-slip ratio, ruptured a structurally segmented fault. Quaternary geomorphic indicators of gross fault-zone morphology reveal both reverse-slip and strike-slip deformation in the rupture area of the 2013 earthquake that varies systematically along fault strike despite nearly pure strike-slip motion in 2013. Observations of along-strike variations in range front relief and geomorphic offsets suggest that the Hoshab fault accommodates a substantial reverse component of fault slip in the Quaternary, especially along the southern section of the 2013 rupture. We surmise that Quaternary bimodal slip along the Hoshab fault is promoted by a combination of the arcuate geometry of the Hoshab fault, the frictional weakness of the Makran accretionary prism, and time variable loading conditions from adjacent earthquakes and plate interactions.

A nonlinear least-squares inverse analysis of strike-slip faulting with application to the San Andreas fault

Science.gov (United States)

Williams, Charles A.; Richardson, Randall M.

1988-01-01

A nonlinear weighted least-squares analysis was performed for a synthetic elastic layer over a viscoelastic half-space model of strike-slip faulting. Also, an inversion of strain rate data was attempted for the locked portions of the San Andreas fault in California. Based on an eigenvector analysis of synthetic data, it is found that the only parameter which can be resolved is the average shear modulus of the elastic layer and viscoelastic half-space. The other parameters were obtained by performing a suite of inversions for the fault. The inversions on data from the northern San Andreas resulted in predicted parameter ranges similar to those produced by inversions on data from the whole fault.

Silurian to Devonian magmatism, molybdenite mineralization, regional exhumation and brittle strike-slip deformation along the Loch Shin Line, NW Scotland

OpenAIRE

Holdsworth, R.; Dempsey, E.; Selby, D.; Darling, James Richard; Feely, M.; Costanzo, A.; Strachan, Robin A; Waters, P.; Finlay, A.J.

2015-01-01

The Loch Shin Line is a geological–geophysical lineament associated with a zone of mantle-derived appinites, granites and strike-slip faulting that runs NW–SE across the Moine Nappe, northern Scotland. U–Pb zircon and Re–Os molybdenite dating of the Loch Shin and Grudie plutons, which lie immediately SW of the NW–SE Loch Shin–Strath Fleet fault system, yield c. 427–430 Ma ages that overlap within error. They also coincide with previously obtained U–Pb zircon ages for the Rogart pluton, which ...

Strike action by nurses in South Africa: A value clarification

Directory of Open Access Journals (Sweden)

Marie Muller

2001-09-01

Full Text Available The Labour Relations Act (South Africa, 1991 made provision for protected strike action by employees, subject to certain conditions, procedures and negotiated agreements. This led to the removal of the strike clause in the Nursing Act (South Africa, 1992. The labour rights of all citizens are entrenched in the Constitution of the country (South Africa, 1996. Participation in strike action by the nurse/ midwife, regardless of the legal requirements and specifications, does, however, pose an ethical question. It is therefore necessary to conduct a value clarification on strike action by nurses in South Africa. The purpose of this research is to explore and describe the perceived values of participants from an accessible population on this phenomenon. A qualitative, exploratory and descriptive research design was deployed. The perceived values of nurses on strike action were collected by means of an openended questionnaire/sketch. Over a period of three years a purposive and convenient sampling method was used, involving all the enrolled post basic nursing/midwifery students/ learners at a particular Nursing Education Institution. The justification of the sample was further enhanced by also collecting data on the participants’ age and provincial distribution location. Although a 63% sample realisation (of the accessible population was achieved, this represents only 1,5% of the registered nursing/midwifery population in the country. A descriptive analysis of the participants’ age and provincial distribution was undertaken, as well as a content analysis of their perceived values on strike action. The mean age of the participants was 48 years, which could be attributed to the fact that most of them were enrolled for a post-basic Diploma in Community Nursing Science. Most of the responses (52,7% were against strike action and 32,5% supported strike action by nurses as a constitutional and legal right. A fairly substantial number of participants (14

Acute transient hemiparesis induced by lightning strike.

Science.gov (United States)

Rahmani, Seyed Hesam; Faridaalaee, Gholamreza; Jahangard, Samira

2015-07-01

According to data from the National Oceanic and Atmospheric Administration,in the years from 1959 to 1994, lightning was responsible for more than 3000 deaths and nearly 10,000 casualties. The most important characteristic features of lightning injuries are multisystem involvement and widely variable severity. Lightning strikes are primarily a neurologic injury that affects all 3 components of the nervous system: central, autonomic,and peripheral. Neurologic complications of lightning strikes vary from transient benign symptoms to permanent disability. Many patients experience a temporary paralysis called keraunoparalysis. Here we reported a 22-year-old mountaineer man with complaining of left sided hemiparesis after being hit by a lightning strike in the mountain 3 hours ago. There was no loss of consciousness at hitting time. On arrival the patient was alert, awake and hemodynamically stable. In neurologic examination cranial nerves were intact, left sided upper and lower extremity muscle force was I/V with a combination of complete sensory loss, and right-sided muscle force and sensory examination were normal. There is not any evidence of significant vascular impairment in the affected extremities. Brain MRI and CT scan and cervical MRI were normal. During 2 days of admission, with intravenous hydration, heparin 5000 unit SC q12hr and physical therapy of the affected limbs, motor and sensory function improved and was normal except mild paresthesia. He was discharged 1 day later for outpatient follow up while vitamin B1 100mg orally was prescribed.Paresthesia improved after 3 days without further sequels.

[Force-feeding of hunger-striking prisoners].

Science.gov (United States)

Glick, Shimon

2014-09-01

In contrast to the position of the World Medical Association and the Ethics Council of the Israel Medical Association, the author argues for forced-feeding of hunger-striking prisoners when their condition reaches a stage of danger of death or permanent injury. This position is based on the priority of human life over autonomy, and of a communitarian ethic. This position is supported by a District Court decision ordering the feeding of a hunger-striking prisoner, by a Supreme Court decision imposing surgery on a non-consenting prisoner, and in line with Israel's Patient's Right Law.

Women, transition and strikes in Serbia

OpenAIRE

Novaković, Nada G.

2014-01-01

The author, in a sociological way, describes and analyzes the concepts of transition, privatization and strikes in Serbia, particularly the place of women in it. It examines the most important economic and social causes and consequences of these phenomena. The main hypothesis is: women's strikes in the Serbian transition are less efficient than strikes and public protests of women in the developed world and the second Yugoslavia. A strike is a class conflict, in which the workers are fighting...

Foot-strike pattern and performance in a marathon.

Science.gov (United States)

Kasmer, Mark E; Liu, Xue-Cheng; Roberts, Kyle G; Valadao, Jason M

2013-05-01

To determine prevalence of heel strike in a midsize city marathon, if there is an association between foot-strike classification and race performance, and if there is an association between foot-strike classification and gender. Foot-strike classification (forefoot, midfoot, heel, or split strike), gender, and rank (position in race) were recorded at the 8.1-km mark for 2112 runners at the 2011 Milwaukee Lakefront Marathon. 1991 runners were classified by foot-strike pattern, revealing a heel-strike prevalence of 93.67% (n = 1865). A significant difference between foot-strike classification and performance was found using a Kruskal-Wallis test (P strike. No significant difference between foot-strike classification and gender was found using a Fisher exact test. In addition, subgroup analysis of the 126 non-heel strikers found no significant difference between shoe wear and performance using a Kruskal-Wallis test. The high prevalence of heel striking observed in this study reflects the foot-strike pattern of most mid-distance to long-distance runners and, more important, may predict their injury profile based on the biomechanics of a heel-strike running pattern. This knowledge can help clinicians appropriately diagnose, manage, and train modifications of injured runners.

A recent Mw 4.3 earthquake proving activity of a shallow strike-slip fault in the northern part of the Western Desert, Egypt

Science.gov (United States)

Ezzelarab, Mohamed; Ebraheem, Mohamed O.; Zahradník, Jiří

2018-03-01

The Mw 4.3 earthquake of September 2015 is the first felt earthquake since 1900 A.D in the northern part of the Western Desert, Egypt, south of the El-Alamein City. The available waveform data observed at epicentral distances 52-391 km was collected and carefully evaluated. Nine broad-band stations were selected to invert full waveforms for the centroid position (horizontal and vertical) and for the focal mechanism solution. The first-arrival travel times, polarities and low-frequency full waveforms (0.03-0.08 Hz) are consistently explained in this paper as caused by a shallow source of the strike-slip mechanism. This finding indicates causal relation of this earthquake to the W-E trending South El-Alamein fault, which developed in Late Cretaceous as dextral strike slip fault. Recent activity of this fault, proven by the studied rare earthquake, is of fundamental importance for future seismic hazard evaluations, underlined by proximity (∼65 km) of the source zone to the first nuclear power plant planned site in Egypt. Safe exploration and possible future exploitation of hydrocarbon reserves, reported around El-Alamein fault in the last decade, cannot be made without considering the seismic potential of this fault.

14 CFR 35.38 - Lightning strike.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Lightning strike. 35.38 Section 35.38... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by... lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...

Options with Extreme Strikes

Directory of Open Access Journals (Sweden)

Lingjiong Zhu

2015-07-01

Full Text Available In this short paper, we study the asymptotics for the price of call options for very large strikes and put options for very small strikes. The stock price is assumed to follow the Black–Scholes models. We analyze European, Asian, American, Parisian and perpetual options and conclude that the tail asymptotics for these option types fall into four scenarios.

Torts Liability for Strike Action and Third Party Rights.

Science.gov (United States)

Raday, Frances

1979-01-01

Studies the nature of the torts liability incurred in strikes and the extent of existing immunities bestowed on strikers and their organizers, and explores the principles that should govern liability and immunity. Available from Israel Law Review Association, c/o Faculty of Law, Hebrew University of Jerusalem, Mount Scopus, P.O.B. 24100, Jerusalem…

[Physicians' strikes--ethical considerations].

Science.gov (United States)

Glick, Shimon; Schwarzfuchs, Dan

2012-01-01

Strikes in general represent a solution based on a form of coercion. Historically, the striker caused direct damage to his employer, who was responsible for the perceived unfair treatment of the employee. In the case of strikes in the public sector, the employer is generally not harmed, but innocent citizens suffer in order to pressure the government agencies, a questionable practice from an ethical viewpoint. Physicians' strikes have more serious ethical problems. They cause suffering and death to innocent citizens. They violate the ethical codes to which physicians have committed themselves as professionals, and they seriously impair the trust of the public in physicians. Better and more ethical ways to provide fair compensation for physicians must be employed, perhaps like those used for judges and members of the IDF.

The Implications of Strike-Slip Earthquake Source Properties on the Transform Boundary Development Process

Science.gov (United States)

Neely, J. S.; Huang, Y.; Furlong, K.

2017-12-01

Subduction-Transform Edge Propagator (STEP) faults, produced by the tearing of a subducting plate, allow us to study the development of a transform plate boundary and improve our understanding of both long-term geologic processes and short-term seismic hazards. The 280 km long San Cristobal Trough (SCT), formed by the tearing of the Australia plate as it subducts under the Pacific plate near the Solomon and Vanuatu subduction zones, shows along-strike variations in earthquake behaviors. The segment of the SCT closest to the tear rarely hosts earthquakes > Mw 6, whereas the SCT sections more than 80 - 100 km from the tear experience Mw7 earthquakes with repeated rupture along the same segments. To understand the effect of cumulative displacement on SCT seismicity, we analyze b-values, centroid-time delays and corner frequencies of the SCT earthquakes. We use the spectral ratio method based on Empirical Green's Functions (eGfs) to isolate source effects from propagation and site effects. We find high b-values along the SCT closest to the tear with values decreasing with distance before finally increasing again towards the far end of the SCT. Centroid time-delays for the Mw 7 strike-slip earthquakes increase with distance from the tear, but corner frequency estimates for a recent sequence of Mw 7 earthquakes are approximately equal, indicating a growing complexity in earthquake behavior with distance from the tear due to a displacement-driven transform boundary development process (see figure). The increasing complexity possibly stems from the earthquakes along the eastern SCT rupturing through multiple asperities resulting in multiple moment pulses. If not for the bounding Vanuatu subduction zone at the far end of the SCT, the eastern SCT section, which has experienced the most displacement, might be capable of hosting larger earthquakes. When assessing the seismic hazard of other STEP faults, cumulative fault displacement should be considered a key input in

Footwear Matters: Influence of Footwear and Foot Strike on Load Rates during Running.

Science.gov (United States)

Rice, Hannah M; Jamison, Steve T; Davis, Irene S

2016-12-01

Running with a forefoot strike (FFS) pattern has been suggested to reduce the risk of overuse running injuries, due to a reduced vertical load rate compared with rearfoot strike (RFS) running. However, resultant load rate has been reported to be similar between foot strikes when running in traditional shoes, leading to questions regarding the value of running with a FFS. The influence of minimal footwear on the resultant load rate has not been considered. This study aimed to compare component and resultant instantaneous loading rate (ILR) between runners with different foot strike patterns in their habitual footwear conditions. Twenty-nine injury-free participants (22 men, seven women) ran at 3.13 m·s along a 30-m runway, with their habitual foot strike and footwear condition. Ground reaction force data were collected. Peak ILR values were compared between three conditions; those who habitually run with an RFS in standard shoes, with an FFS in standard shoes, and with an FFS in minimal shoes. Peak resultant, vertical, lateral, and medial ILR were lower (P strike. When running with an FFS, peak posterior ILR were lower (P strike. Therefore, it appears that footwear alters the load rates during running, even with similar foot strike patterns.

Effect of public transport strikes on air pollution levels in Barcelona (Spain).

Science.gov (United States)

Basagaña, Xavier; Triguero-Mas, Margarita; Agis, David; Pérez, Noemí; Reche, Cristina; Alastuey, Andrés; Querol, Xavier

2018-01-01

Public transport strikes can lead to an increase of the number of private vehicle trips, which in turn can increase air pollution levels. We aimed to estimate the change in air pollution concentrations during public transport strikes in the city of Barcelona (Spain). Data on strikes of the metro, train or bus systems were collected from government records (2005-2016). We collected daily concentrations of NOx; particulate matter with an aerodynamic diameter smaller than 10μm (PM10), 2.5μm (PM2.5), and 1μm (PM1); particle number concentration (N); black carbon (BC) and CO from research and official monitoring stations. We fitted linear regression models for each pollutant with the strike indicator as an independent variable, and models were adjusted for day of the week, month, year, and holiday periods. During the study period, there were 208days affected by a strike of the metro (28), train (106) or bus (91) systems. Half of the strikes were partial, most of them were single-day strikes, there was little overlap between strikes of the different transport systems, and all strikes had to comply with mandatory minimal services. When pooling all types of strikes, NOx and BC showed higher levels during strike days in comparison with non-strike days (increase between 4.1% and 7.7%, with higher increases for NO). The increases in these concentrations were more evident during full day and multiday metro strikes. In conclusion, alterations in public transport have consequences on air quality. This highlights the importance of public transport in reducing air pollution concentrations in cities. Copyright © 2017 Elsevier B.V. All rights reserved.

Fault Branching and Long-Term Earthquake Rupture Scenario for Strike-Slip Earthquake

Science.gov (United States)

Klinger, Y.; CHOI, J. H.; Vallage, A.

2017-12-01

Careful examination of surface rupture for large continental strike-slip earthquakes reveals that for the majority of earthquakes, at least one major branch is involved in the rupture pattern. Often, branching might be either related to the location of the epicenter or located toward the end of the rupture, and possibly related to the stopping of the rupture. In this work, we examine large continental earthquakes that show significant branches at different scales and for which ground surface rupture has been mapped in great details. In each case, rupture conditions are described, including dynamic parameters, past earthquakes history, and regional stress orientation, to see if the dynamic stress field would a priori favor branching. In one case we show that rupture propagation and branching are directly impacted by preexisting geological structures. These structures serve as pathways for the rupture attempting to propagate out of its shear plane. At larger scale, we show that in some cases, rupturing a branch might be systematic, hampering possibilities for the development of a larger seismic rupture. Long-term geomorphology hints at the existence of a strong asperity in the zone where the rupture branched off the main fault. There, no evidence of throughgoing rupture could be seen along the main fault, while the branch is well connected to the main fault. This set of observations suggests that for specific configurations, some rupture scenarios involving systematic branching are more likely than others.

A bird strike handbook for base-level managers

Science.gov (United States)

Payson, R. P.; Vance, J. D.

1984-09-01

To help develop more awareness about bird strikes and bird strike reduction techniques, this thesis compiled all relevant information through an extensive literature search, review of base-level documents, and personal interviews. The final product--A Bird Strike Handbook for Base-Level Managers--provides information on bird strike statistics, methods to reduce the strike hazards, and means to obtain additional assistance. The handbook is organized for use by six major base agencies: Maintenance, Civil Engineering, Operations, Air Field Management, Safety, and Air Traffic Control. An appendix follows at the end.

Is the foot striking pattern more important than barefoot or shod conditions in running?

Science.gov (United States)

Shih, Yo; Lin, Kuan-Lun; Shiang, Tzyy-Yuang

2013-07-01

People have advocated barefoot running, claiming that it is better suited to human nature. Humans usually run barefoot using a forefoot strike and run shod using a heel strike. The striking pattern was thought to be a key factor that contributes to the benefit of barefoot running. The purpose of this study is to use scientific data to prove that the striking pattern is more important than barefoot or shod conditions for runners on running injuries prevention. Twelve habitually male shod runners were recruited to run under four varying conditions: barefoot running with a forefoot strike, barefoot running with a heel strike, shod running with a forefoot strike, and shod running with a heel strike. Kinetic and kinematic data and electromyography signals were recorded during the experiments. The results showed that the lower extremity can gain more compliance when running with a forefoot strike. Habitually shod runners can gain more shock absorption by changing the striking pattern to a forefoot strike when running with shoes and barefoot conditions. Habitually shod runners may be subject to injuries more easily when they run barefoot while maintaining their heel strike pattern. Higher muscle activity in the gastrocnemius was observed when running with a forefoot strike, which may imply a greater training load on the muscle and a tendency for injury. Copyright © 2013 Elsevier B.V. All rights reserved.

Collective Labor Disputes and Strikes in Russia: The Impact of Judicial Precedents and Enforcement

Directory of Open Access Journals (Sweden)

Elena Gerasimova

2017-01-01

Full Text Available The right to strike is recognized in the Constitution and the Labor Code of the Russian Federation as a means to resolve collective labor disputes. However, in Russia labor protests come up for discussion much more frequently than strikes. In recent years the number of labor protests in Russia, including various forms of work stoppage, has increased significantly compared to previous years, but the number of legally constituted collective labor disputes and strikes has remained very low. The legislation on resolution of collective labor disputes and mounting strikes is quite restrictive in Russia, and its enforcement also encourages employees to seek alternative ways to settle collective labor conflicts. There is little empirical research on the judicial implementation of these norms and its influence on the enforcement of legislation. Therefore, this paper analyses the reasoning of courts in cases on the legality of strikes, their interpretations of the law, and the impact these decisions have on the enforcement of the legislation on resolution of collective labor disputes and strikes. Our conclusion is that the courts act as another restrictive influence on the resolution of collective labor disputes and the exercise of the right to strike in Russia.

Seismic Evidence for Conjugate Slip and Block Rotation Within the San Andreas Fault System, Southern California

Science.gov (United States)

Nicholson, Craig; Seeber, Leonardo; Williams, Patrick; Sykes, Lynn R.

1986-08-01

The pattern of seismicity in southern California indicates that much of the activity is presently occurring on secondary structures, several of which are oriented nearly orthogonal to the strikes of the major through-going faults. Slip along these secondary transverse features is predominantly left-lateral and is consistent with the reactivation of conjugate faults by the current regional stress field. Near the intersection of the San Jacinto and San Andreas faults, however, these active left-lateral faults appear to define a set of small crustal blocks, which in conjunction with both normal and reverse faulting earthquakes, suggests contemporary clockwise rotation as a result of regional right-lateral shear. Other left-lateral faults representing additional rotating block systems are identified in adjacent areas from geologic and seismologic data. Many of these structures predate the modern San Andreas system and may control the pattern of strain accumulation in southern California. Geodetic and paleomagnetic evidence confirm that block rotation by strike-slip faulting is nearly ubiquitous, particularly in areas where shear is distributed, and that it accommodates both short-term elastic and long-term nonelastic strain. A rotating block model accounts for a number of structural styles characteristic of strike-slip deformation in California, including: variable slip rates and alternating transtensional and transpressional features observed along strike of major wrench faults; domains of evenly-spaced antithetic faults that terminate against major fault boundaries; continued development of bends in faults with large lateral displacements; anomalous focal mechanisms; and differential uplift in areas otherwise expected to experience extension and subsidence. Since block rotation requires a detachment surface at depth to permit rotational movement, low-angle structures like detachments, of either local or regional extent, may be involved in the contemporary strike-slip

Foot strike patterns after obstacle clearance during running.

Science.gov (United States)

Scholten, Shane D; Stergiou, Nicholas; Hreljac, Alan; Houser, Jeremy; Blanke, Daniel; Alberts, L Russell

2002-01-01

Running over obstacles of sufficient height requires heel strike (HS) runners to make a transition in landing strategy to a forefoot (FF) strike, resulting in similar ground reaction force patterns to those observed while landing from a jump. Identification of the biomechanical variables that distinguish between the landing strategies may offer some insight into the reasons that the transition occurs. The purpose of this study was to investigate the difference in foot strike patterns and kinetic parameters of heel strike runners between level running and running over obstacles of various heights. Ten heel strike subjects ran at their self-selected pace under seven different conditions: unperturbed running (no obstacle) and over obstacles of six different heights (10%, 12.5%, 15%, 17.5%, 20%, and 22.5% of their standing height). The obstacle was placed directly before a Kistler force platform. Repeated measures ANOVAs were performed on the subject means of selected kinetic parameters. The statistical analysis revealed significant differences (P strike patterns were affected by the increased obstacle height. Between the 12.5% and 15% obstacle conditions, the group response changed from a heel strike to a forefoot strike pattern. At height > 15%, the pattern was more closely related to the foot strike patterns found in jumping activities. This strategy change may represent a gait transition effected as a mechanism to protect against increased impact forces. Greater involvement of the ankle and the calf muscles could have assisted in attenuating the increased impact forces while maintaining speed after clearing the obstacle.

Strikes and solidarity: coalfield conflict in Britain, 1889-1966

Energy Technology Data Exchange (ETDEWEB)

Roy Church; Quentin Outram [University of East Anglia, Norwich (United Kingdom)

2002-05-01

This book investigates the history of strike activity in the British coal mining industry, a byword for industrial militancy since the late nineteenth century. Contents: 1. Interpreting coalfield conflict: focus and formulations; 2. Tradition and modernity: the mining industry 1889-1940; 3. Employers and workers: organizations and strategies; 4. Employers and workers: ideologies, attitudes and political orientations; 5. Configurations of strike activity; 6. Strike participation and solidarity before 1912; 7. Strikes, organization and consciousness in 1912 and after; 8. Conflictual context? The 'isolated mass' revisited; 9. Mining and modernity: size, sectionalism and solidarity; 10. The foundations of strike propensity; 11. Miners and management: agency and action; 12. Industrial relations and strikes after nationalization; 13. International perspectives; 14. Myths and realities: strikes, solidarity and 'militant miners'.

The effects of preferred and non-preferred running strike patterns on tissue vibration properties.

Science.gov (United States)

Enders, Hendrik; von Tscharner, Vinzenz; Nigg, Benno M

2014-03-01

To characterize soft tissue vibrations during running with a preferred and a non-preferred strike pattern in shoes and barefoot. Cross-sectional study. Participants ran at 3.5 m s(-1) on a treadmill in shoes and barefoot using a rearfoot and a forefoot strike for each footwear condition. The preferred strike patterns for the subjects were a rearfoot strike and a forefoot strike for shod and barefoot running, respectively. Vibrations were recorded with an accelerometer overlying the belly of the medial gastrocnemius. Thirteen non-linearly scaled wavelets were used for the analysis. Damping was calculated as the overall decay of power in the acceleration signal post ground contact. A higher damping coefficient indicates higher damping capacities of the soft tissue. The shod rearfoot strike showed a 93% lower damping coefficient than the shod forefoot strike (pforefoot strike showed a trend toward a lower damping coefficient compared to a barefoot rearfoot strike. Running barefoot with a forefoot strike resulted in a significantly lower damping coefficient than a forefoot strike when wearing shoes (pstrike showed lower damping compared to a barefoot rearfoot strike (p<0.001). While rearfoot striking showed lower vibration frequencies in shod and barefoot running, it did not consistently result in lower damping coefficients. This study showed that the use of a preferred movement resulted in lower damping coefficients of running related soft tissue vibrations. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Estimating the Impact of Bird Strikes

NARCIS (Netherlands)

Metz, I.C.; Muhlhausen, Thorsten; Ellerbroek, J.; Hoekstra, J.M.

2018-01-01

Bird strikes have the potential to cause severe damage to aircraft. Therefore, measures to reduce the risk of bird strikes are performed at airports. However, this risk is not limited to the airport but is increased in the arrival and departure corridors as well. Consequently, a significant amount

Earthquake Activities Along the Strike-Slip Fault System on the Thailand-Myanmar Border

Directory of Open Access Journals (Sweden)

Santi Pailoplee

2014-01-01

Full Text Available This study investigates the present-day seismicity along the strike-slip fault system on the Thailand-Myanmar border. Using the earthquake catalogue the earthquake parameters representing seismic activities were evaluated in terms of the possible maximum magnitude, return period and earthquake occurrence probabilities. Three different hazardous areas could be distinguished from the obtained results. The most seismic-prone area was located along the northern segment of the fault system and can generate earthquakes of magnitude 5.0, 5.8, and 6.8 mb in the next 5, 10, and 50 years, respectively. The second most-prone area was the southern segment where earthquakes of magnitude 5.0, 6.0, and 7.0 mb might be generated every 18, 60, and 300 years, respectively. For the central segment, there was less than 30 and 10% probability that 6.0- and 7.0-mb earthquakes will be generated in the next 50 years. With regards to the significant infrastructures (dams in the vicinity, the operational Wachiralongkorn dam is situated in a low seismic hazard area with a return period of around 30 - 3000 years for a 5.0 - 7.0 mb earthquake. In contrast, the Hut Gyi, Srinakarin and Tha Thung Na dams are seismically at risk for earthquakes of mb 6.4 - 6.5 being generated in the next 50 years. Plans for a seismic-retrofit should therefore be completed and implemented while seismic monitoring in this region is indispensable.

BIRD/WILDLIFE STRIKE CONTROL FOR SAFER AIR ...

African Journals Online (AJOL)

Osondu

2012-06-05

Jun 5, 2012 ... Keywords: bird/wildlife, strike, aviation, hazard, control. Introduction ... Ethiopian Journal of Environmental Studies and Management EJESM Vol. 5 No. 3 2012 .... Aircraft Bird. Strike Avoidance Rader System (ABARS) and.

MORE THAN A LABOR DISPUTE: THE PATCO STRIKE OF 1981

Directory of Open Access Journals (Sweden)

Paul L. Butterworth

2005-01-01

Full Text Available On August 3, 1981, 13,000 air traffic controllers walked off the job. Under US law, the strike was illegal. President Ronald Reagan ordered the strikers as a group to return to work; when they did not, he ordered individual strikers to return, and again they refused. Two days later the president fired the strikers. Reagan's action transformed relations between organized labor and American management, and created the worst turbulence to hit the American airways in recent history. “More Than a Labor Dispute” examines the work stoppage and aftermath through the eyes of two controllers and a pilot, all of whom worked during the strike.

Determine the Foot Strike Pattern Using Inertial Sensors

Directory of Open Access Journals (Sweden)

Tzyy-Yuang Shiang

2016-01-01

Full Text Available From biomechanical point of view, strike pattern plays an important role in preventing potential injury risk in running. Traditionally, strike pattern determination was conducted by using 3D motion analysis system with cameras. However, the procedure is costly and not convenient. With the rapid development of technology, sensors have been applied in sport science field lately. Therefore, this study was designed to determine the algorithm that can identify landing strategies with a wearable sensor. Six healthy male participants were recruited to perform heel and forefoot strike strategies at 7, 10, and 13 km/h speeds. The kinematic data were collected by Vicon 3D motion analysis system and 2 inertial measurement units (IMU attached on the dorsal side of both shoes. The data of each foot strike were gathered for pitch angle and strike index analysis. Comparing the strike index from IMU with the pitch angle from Vicon system, our results showed that both signals exhibited highly correlated changes between different strike patterns in the sagittal plane (r=0.98. Based on the findings, the IMU sensors showed potential capabilities and could be extended beyond the context of sport science to other fields, including clinical applications.

A decade of U.S. Air Force bat strikes

Science.gov (United States)

Peurach, Suzanne C.; Dove, Carla J.; Stepko, Laura

2009-01-01

From 1997 through 2007, 821 bat strikes were reported to the U.S. Air Force (USAF) Safety Center by aircraft personnel or ground crew and sent to the National Museum of Natural History, Smithsonian Institution, for identification. Many samples were identified by macroscopic and or microscopic comparisons with bat specimens housed in the museum and augmented during the last 2 years by DNA analysis. Bat remains from USAF strikes during this period were received at the museum from 40 states in the United States and from 20 countries. We confirmed that 46% of the strikes were caused by bats, but we did not identify them further; we identified 5% only to the family or genus level, and 49% to the species level. Fifty-five of the 101 bat-strike samples submitted for DNA analysis have been identified to the species level. Twenty-five bat species have been recorded striking USAF planes worldwide. The Brazilian free-tailed bat (Tadarida brasiliensis; n = 173) is the species most commonly identified in USAF strike impacts, followed by the red bat (Lasiurus borealis; n = 83). Bat strikes peak during the spring and fall, with >57% occurring from August through October; 82% of the reports that included time of strike were recorded between 2100 and 0900 hours. More than 12% of the bat strikes were reported at >300 m above ground level (AGL). Although $825,000 and >50% of this sum was attributable to 5 bat-strike incidents. Only 5 bats from the 10 most damaging bat strikes were identified to the species level, either because we did not receive remains with the reports or the sample was insufficient for identification.

2002 Bird Strike Committee USA/Canada Conference

National Research Council Canada - National Science Library

Dolbeer, Richard

2002-01-01

Over 380 people from 20 countries and 17 exhibitors attended the 4th annual joint meeting of Bird Strike Committee-USA and Bird Strike Committee Canada in Sacramento, California on October 21-24, 2002...

Wavelet transform analysis of electromyography kung fu strikes data.

Science.gov (United States)

Neto, Osmar Pinto; Marzullo, Ana Carolina de Miranda

2009-11-01

In martial arts and contact sports strikes are performed at near maximum speeds. For that reason, electromyography (EMG) analysis of such movements is non-trivial. This paper has three main goals: firstly, to investigate the differences in the EMG activity of muscles during strikes performed with and without impacts; secondly, to assess the advantages of using Sum of Significant Power (SSP) values instead of root mean square (rms) values when analyzing EMG data; and lastly to introduce a new method of calculating median frequency values using wavelet transforms (WMDF). EMG data of the deltoid anterior (DA), triceps brachii (TB) and brachioradialis (BR) muscles were collected from eight Kung Fu practitioners during strikes performed with and without impacts. SSP results indicated significant higher muscle activity (p = 0.023) for the strikes with impact. WMDF results, on the other hand, indicated significant lower values (p = 0. 007) for the strikes with impact. SSP results presented higher sensitivity than rms to quantify important signal differences and, at the same time, presented lower inter-subject coefficient of variations. The result of increase in SSP values and decrease in WMDF may suggest better synchronization of motor units for the strikes with impact performed by the experienced Kung Fu practitioners. Key PointsThe results show higher muscle activity and lower electromyography median frequencies for strikes with impact compared to strikes without.SSP results presented higher sensitivity and lower inter-subject coefficient of variations than rms results.Kung Fu palm strikes with impact may present better motor units' synchronization than strikes without.

When Push Comes to Shove: Strikes in Higher Education.

Science.gov (United States)

Magney, John

2002-01-01

To provide a better sense of how academic unions handle a strike situation, examines six unions who, between 1996 and 2000, went through strikes. Discusses the key issues and outcomes of the strikes. (EV)

Lower limb joint angles and ground reaction forces in forefoot strike and rearfoot strike runners during overground downhill and uphill running.

Science.gov (United States)

Kowalski, Erik; Li, Jing Xian

2016-11-01

This study investigated the normal and parallel ground reaction forces during downhill and uphill running in habitual forefoot strike and habitual rearfoot strike (RFS) runners. Fifteen habitual forefoot strike and 15 habitual RFS recreational male runners ran at 3 m/s ± 5% during level, uphill and downhill overground running on a ramp mounted at 6° and 9°. Results showed that forefoot strike runners had no visible impact peak in all running conditions, while the impact peaks only decreased during the uphill conditions in RFS runners. Active peaks decreased during the downhill conditions in forefoot strike runners while active loading rates increased during downhill conditions in RFS runners. Compared to the level condition, parallel braking peaks were larger during downhill conditions and parallel propulsive peaks were larger during uphill conditions. Combined with previous biomechanics studies, our findings suggest that forefoot strike running may be an effective strategy to reduce impacts, especially during downhill running. These findings may have further implications towards injury management and prevention.

Patellofemoral joint stress during running with alterations in foot strike pattern.

Science.gov (United States)

Vannatta, Charles Nathan; Kernozek, Thomas W

2015-05-01

This study aimed to quantify differences in patellofemoral joint stress that may occur when healthy runners alter their foot strike pattern from their habitual rearfoot strike to a forefoot strike to gain insight on the potential etiology and treatment methods of patellofemoral pain. Sixteen healthy female runners completed 20 running trials in a controlled laboratory setting under rearfoot strike and forefoot strike conditions. Kinetic and kinematic data were used to drive a static optimization technique to estimate individual muscle forces to input into a model of the patellofemoral joint to estimate joint stress during running. Peak patellofemoral joint stress and the stress-time integral over stance phase decreased by 27% and 12%, respectively, in the forefoot strike condition (P forefoot strike condition (P forefoot strike (P forefoot strike condition (P strike pattern to a forefoot strike results in consistent reductions in patellofemoral joint stress independent of changes in step length. Thus, implementation of forefoot strike training programs may be warranted in the treatment of runners with patellofemoral pain. However, it is suggested that the transition to a forefoot strike pattern should be completed in a graduated manner.

Martial arts striking hand peak acceleration, accuracy and consistency.

Science.gov (United States)

Neto, Osmar Pinto; Marzullo, Ana Carolina De Miranda; Bolander, Richard P; Bir, Cynthia A

2013-01-01

The goal of this paper was to investigate the possible trade-off between peak hand acceleration and accuracy and consistency of hand strikes performed by martial artists of different training experiences. Ten male martial artists with training experience ranging from one to nine years volunteered to participate in the experiment. Each participant performed 12 maximum effort goal-directed strikes. Hand acceleration during the strikes was obtained using a tri-axial accelerometer block. A pressure sensor matrix was used to determine the accuracy and consistency of the strikes. Accuracy was estimated by the radial distance between the centroid of each subject's 12 strikes and the target, whereas consistency was estimated by the square root of the 12 strikes mean squared distance from their centroid. We found that training experience was significantly correlated to hand peak acceleration prior to impact (r(2)=0.456, p =0.032) and accuracy (r(2)=0. 621, p=0.012). These correlations suggest that more experienced participants exhibited higher hand peak accelerations and at the same time were more accurate. Training experience, however, was not correlated to consistency (r(2)=0.085, p=0.413). Overall, our results suggest that martial arts training may lead practitioners to achieve higher striking hand accelerations with better accuracy and no change in striking consistency.

Orthotic intervention in forefoot and rearfoot strike running patterns.

Science.gov (United States)

Stackhouse, Carrie Laughton; Davis, Irene McClay; Hamill, Joseph

2004-01-01

To compare the differential effect of custom orthoses on the lower extremity mechanics of a forefoot and rearfoot strike pattern. Fifteen subjects ran with both a forefoot and a rearfoot strike pattern with and without orthoses. Lower extremity kinematic and kinetic variables were compared between strike pattern and orthotic conditions. Foot orthoses have been shown to be effective in controlling excessive rearfoot motion in rearfoot strikers. The effect of orthotic intervention on rearfoot motion in forefoot strikers has not been previously reported. Five trials were collected for each condition. Peak rearfoot eversion, eversion excursion, eversion velocity, peak inversion moment, and inversion work were compared between conditions. Kinematic variables in the sagittal plane of the rearfoot and in the frontal and sagittal plane of the knee were also determined. Increased rearfoot excursions and velocities and decreased peak eversion were noted in the forefoot strike pattern compared to the rearfoot strike pattern. Orthotic intervention, however,did not significantly change rearfoot motion in either strike pattern. Reductions in internal rotation and abduction of the knee were noted with orthotic intervention. Foot orthoses do not differentially effect rearfoot motion of a rearfoot strike and a forefoot strike running pattern. Orthotic intervention has a larger and more systematic effect on rearfoot kinetics compared to rearfoot kinematics.

VARIATION OF STRIKE INCENTIVES IN DEEP REDUCTIONS; FINAL

International Nuclear Information System (INIS)

G.H. CANAVAN

2001-01-01

This note studies the sensitivity of strike incentives to deep offensive force reductions using exchange, cost, and game theoretic decision models derived and discussed in companion reports. As forces fall, weapon allocations shift from military to high value targets, with the shift being half complete at about 1,000 weapons. By 500 weapons, the first and second strikes are almost totally on high value. The dominant cost for striking first is that of damage to one's high value, which is near total absent other constraints, and hence proportional to preferences for survival of high value. Changes in military costs are largely offsetting, so total first strike costs change little. The resulting costs at decision nodes are well above the costs of inaction, so the preferred course is inaction for all offensive reductions studied. As the dominant cost for striking first is proportional to the preference for survival of high value. There is a wide gap between the first strike cost and that of inaction for the parameters studied here. These conclusions should be insensitive to significant reductions in the preference for survival of high value, which is the most sensitive parameter

The last interglacial period at Guantanamo Bay, Cuba and an estimate of late Quaternary tectonic uplift rate in a strike-slip regime

Science.gov (United States)

Schweig, E. S.; Muhs, D. R.; Simmons, K. R.; Halley, R. B.

2015-12-01

Guantanamo Bay, Cuba is an area dominated by a strike-slip tectonic regime and is therefore expected to have very low Quaternary uplift rates. We tested this hypothesis by study of an unusually well preserved emergent reef terrace around the bay. Up to 12 m of unaltered, growth-position reef corals are exposed at about 40 sections examined around ˜40 km of coastline. Maximum reef elevations in the protected, inner part of the bay are ˜11-12 m, whereas outer-coast shoreline angles of wave-cut benches are as high as ˜14 m. Fifty uranium-series analyses of unrecrystallized corals from six localities yield ages ranging from ˜134 ka to ˜115 ka, when adjusted for small biases due to slightly elevated initial 234U/238U values. Thus, ages of corals correlate this reef to the peak of the last interglacial period, marine isotope stage (MIS) 5.5. Previously, we dated the Key Largo Limestone to the same high-sea stand in the tectonically stable Florida Keys. Estimates of paleo-sea level during MIS 5.5 in the Florida Keys are ~6.6 to 8.3 m above present. Assuming a similar paleo-sea level in Cuba, this yields a long-term tectonic uplift rate of 0.04-0.06 m/ka over the past ~120 ka. This estimate supports the hypothesis that the tectonic uplift rate should be low in this strike-slip regime. Nevertheless, on the southeast coast of Cuba, east of our study area, we have observed flights of multiple marine terraces, suggesting either (1) a higher uplift rate or (2) an unusually well-preserved record of pre-MIS 5.5 terraces not observed at Guantanamo Bay.

[Hunger striking in prisons: ethics and the ethical and legal aspects].

Science.gov (United States)

García-Guerrero, J

2013-01-01

Hunger strike is a common form of protest in prisons and is a potential cause of many types of problems, both for the prison administration and the doctors who care for prisoners who participate in one. Issues of conflict of rights and obligations involved, and how to treat people who are subject to the Administration, which in this case takes the position of guarantor, have created major controversies over doctrine. Conscientious objection and the conflict of dual loyalty of doctors working in prisons are also issues closely linked to a prison hunger strike. In this paper we review the solution given to the problem of treatment of a prison hunger strike from three perspectives: ethics, ethical and legal.

Fault Slip Partitioning in the Eastern California Shear Zone-Walker Lane Belt: Pliocene to Late Pleistocene Contraction Across the Mina Deflection

Science.gov (United States)

Lee, J.; Stockli, D.; Gosse, J.

2007-12-01

Two different mechanisms have been proposed for fault slip transfer between the subparallel NW-striking dextral- slip faults that dominant the Eastern California Shear Zone (ECSZ)-Walker Lane Belt (WLB). In the northern WLB, domains of sinistral-slip along NE-striking faults and clockwise block rotation within a zone of distributed deformation accommodated NW-dextral shear. A somewhat modified version of this mechanism was also proposed for the Mina deflection, southern WLB, whereby NE-striking sinistral faults formed as conjugate faults to the primary zone of NW-dextral shear; clockwise rotation of the blocks bounding the sinistral faults accommodated dextral slip. In contrast, in the northern ECSZ and Mina deflection, domains of NE-striking pure dip-slip normal faults, bounded by NW-striking dextral-slip faults, exhibited no rotation; the proposed mechanism of slip transfer was one of right-stepping, high angle normal faults in which the magnitude of extension was proportional to the amount of strike-slip motion transferred. New geologic mapping, tectonic geomorphologic, and geochronologic data from the Queen Valley area, southern Mina deflection constrain Pliocene to late Quaternary fault geometries, slip orientations, slip magnitudes, and slip rates that bear on the mechanism of fault slip transfer from the relatively narrow northern ECSZ to the broad deformation zone that defines the Mina deflection. Four different fault types and orientations cut across the Queen Valley area: (1) The NE-striking normal-slip Queen Valley fault; (2) NE-striking sinistral faults; (3) the NW-striking dextral Coyote Springs fault, which merges into (4) a set of EW-striking thrust faults. (U-Th)/He apatite and cosmogenic radionuclide data, combined with magnitude of fault offset measurements, indicate a Pliocene to late Pleistocene horizontal extension rate of 0.2-0.3 mm/yr across the Queen Valley fault. Our results, combined with published slip rates for the dextral White Mountain

Pan-African deformations in the basement of the Negele area, southern Ethiopia

Science.gov (United States)

Yihunie, Tadesse

2002-03-01

Polydeformed and metamorphosed Neoproterozoic rocks of the East African Orogen in the Negele area constituted three lithostructurally distinct and thrust-bounded terranes. These are, from west to east, the Kenticha, Alghe and Bulbul terranes. The Kenticha and Bulbul terranes are metavolcano-sedimentary and ultramafic sequences, representing parts of the Arabian-Nubian Shield (ANS), which are welded to the central Alghe gneissic terrane of the Mozambique Belt affinity along N-S-trending sheared thrust contacts. Structural data suggest that the Negele basement had evolved through three phases of deformation. During D1 (folding) deformation, north-south upright and inclined folds with north-trending axes were developed. East and west-verging thrusts, right-lateral shearing along the north-oriented Kenticha and Bulbul thrust contacts and related structural elements were developed during D2 (thrusting) deformation. The pervasive D1 event is interpreted to have occurred at 620-610 Ma and the D2 event ended prior to 554 Ma. Right-lateral strike-slips along thrust contacts are interpreted to have been initiated during late D2. During D3, left-lateral strike-slip along the Wadera Shear Zone and respective strike-slip movements along conjugate set of shear zones were developed in the Alghe terrane, and are interpreted to have occurred later than 557 Ma. The structural data suggest that eastward thrusting of the Kenticha and westward tectonic transport of the Bulbul sequences over the Alghe gneissic terrane of the Mozambique Belt, during D2, were accompanied by right-lateral strike-slip displacements along thrust contacts. Right-lateral strike-slip movements along the Kenticha thrust contact, further suggest northward movement of the Kenticha sequence during the Pan-African orogeny in the Neoproterozoic. Left-lateral strike-slip along the orogen-parallel NNE-SSW Wadera Shear Zone and strike-slip movements along a conjugate set of shear zones completed final terrane

Foot strike patterns of recreational and sub-elite runners in a long-distance road race.

Science.gov (United States)

Larson, Peter; Higgins, Erin; Kaminski, Justin; Decker, Tamara; Preble, Janine; Lyons, Daniela; McIntyre, Kevin; Normile, Adam

2011-12-01

Although the biomechanical properties of the various types of running foot strike (rearfoot, midfoot, and forefoot) have been studied extensively in the laboratory, only a few studies have attempted to quantify the frequency of running foot strike variants among runners in competitive road races. We classified the left and right foot strike patterns of 936 distance runners, most of whom would be considered of recreational or sub-elite ability, at the 10 km point of a half-marathon/marathon road race. We classified 88.9% of runners at the 10 km point as rearfoot strikers, 3.4% as midfoot strikers, 1.8% as forefoot strikers, and 5.9% of runners exhibited discrete foot strike asymmetry. Rearfoot striking was more common among our sample of mostly recreational distance runners than has been previously reported for samples of faster runners. We also compared foot strike patterns of 286 individual marathon runners between the 10 km and 32 km race locations and observed increased frequency of rearfoot striking at 32 km. A large percentage of runners switched from midfoot and forefoot foot strikes at 10 km to rearfoot strikes at 32 km. The frequency of discrete foot strike asymmetry declined from the 10 km to the 32 km location. Among marathon runners, we found no significant relationship between foot strike patterns and race times.

A simple field method to identify foot strike pattern during running.

Science.gov (United States)

Giandolini, Marlène; Poupard, Thibaut; Gimenez, Philippe; Horvais, Nicolas; Millet, Guillaume Y; Morin, Jean-Benoît; Samozino, Pierre

2014-05-07

Identifying foot strike patterns in running is an important issue for sport clinicians, coaches and footwear industrials. Current methods allow the monitoring of either many steps in laboratory conditions or only a few steps in the field. Because measuring running biomechanics during actual practice is critical, our purpose is to validate a method aiming at identifying foot strike patterns during continuous field measurements. Based on heel and metatarsal accelerations, this method requires two uniaxial accelerometers. The time between heel and metatarsal acceleration peaks (THM) was compared to the foot strike angle in the sagittal plane (αfoot) obtained by 2D video analysis for various conditions of speed, slope, footwear, foot strike and state of fatigue. Acceleration and kinematic measurements were performed at 1000Hz and 120Hz, respectively, during 2-min treadmill running bouts. Significant correlations were observed between THM and αfoot for 14 out of 15 conditions. The overall correlation coefficient was r=0.916 (Pstrike except for extreme forefoot strike during which the heel rarely or never strikes the ground, and for different footwears and states of fatigue. We proposed a classification based on THM: FFS<-5.49msrights reserved.

Slicing up the San Francisco Bay Area: Block kinematics and fault slip rates from GPS-derived surface velocities

Science.gov (United States)

d'Alessio, M. A.; Johanson, I.A.; Burgmann, R.; Schmidt, D.A.; Murray, M.H.

2005-01-01

Observations of surface deformation allow us to determine the kinematics of faults in the San Francisco Bay Area. We present the Bay Area velocity unification (BA??VU??, "bay view"), a compilation of over 200 horizontal surface velocities computed from campaign-style and continuous Global Positioning System (GPS) observations from 1993 to 2003. We interpret this interseismic velocity field using a three-dimensional block model to determine the relative contributions of block motion, elastic strain accumulation, and shallow aseismic creep. The total relative motion between the Pacific plate and the rigid Sierra Nevada/Great Valley (SNGV) microplate is 37.9 ?? 0.6 mm yr-1 directed toward N30.4??W ?? 0.8?? at San Francisco (??2??). Fault slip rates from our preferred model are typically within the error bounds of geologic estimates but provide a better fit to geodetic data (notable right-lateral slip rates in mm yr-1: San Gregorio fault, 2.4 ?? 1.0; West Napa fault, 4.0 ?? 3.0; zone of faulting along the eastern margin of the Coast Range, 5.4 ?? 1.0; and Mount Diablo thrust, 3.9 ?? 1.0 of reverse slip and 4.0 ?? 0.2 of right-lateral strike slip). Slip on the northern Calaveras is partitioned between both the West Napa and Concord/ Green Valley fault systems. The total convergence across the Bay Area is negligible. Poles of rotation for Bay Area blocks progress systematically from the North America-Pacific to North America-SNGV poles. The resulting present-day relative motion cannot explain the strike of most Bay Area faults, but fault strike does loosely correlate with inferred plate motions at the time each fault initiated. Copyright 2005 by the American Geophysical Union.

Joint stiffness and running economy during imposed forefoot strike before and after a long run in rearfoot strike runners.

Science.gov (United States)

Melcher, Daniel A; Paquette, Max R; Schilling, Brian K; Bloomer, Richard J

2017-12-01

Research has focused on the effects of acute strike pattern modifications on lower extremity joint stiffness and running economy (RE). Strike pattern modifications on running biomechanics have mostly been studied while runners complete short running bouts. This study examined the effects of an imposed forefoot strike (FFS) on RE and ankle and knee joint stiffness before and after a long run in habitual rearfoot strike (RFS) runners. Joint kinetics and RE were collected before and after a long run. Sagittal joint kinetics were computed from kinematic and ground reaction force data that were collected during over-ground running trials in 13 male runners. RE was measured during treadmill running. Knee flexion range of motion, knee extensor moment and ankle joint stiffness were lower while plantarflexor moment and knee joint stiffness were greater during imposed FFS compared with RFS. The long run did not influence the difference in ankle and knee joint stiffness between strike patterns. Runners were more economical during RFS than imposed FFS and RE was not influenced by the long run. These findings suggest that using a FFS pattern towards the end of a long run may not be mechanically or metabolically beneficial for well-trained male RFS runners.

Management of patients during hunger strike and refeeding phase.

Science.gov (United States)

Eichelberger, M; Joray, M L; Perrig, M; Bodmer, M; Stanga, Z

2014-01-01

Hunger strikers resuming nutritional intake may develop a life-threatening refeeding syndrome (RFS). Consequently, hunger strikers represent a core challenge for the medical staff. The objective of the study was to test the effectiveness and safety of evidence-based recommendations for prevention and management of RFS during the refeeding phase. This was a retrospective, observational data analysis of 37 consecutive, unselected cases of prisoners on a hunger strike during a 5-y period. The sample consisted of 37 cases representing 33 individual patients. In seven cases (18.9%), the hunger strike was continued during the hospital stay, in 16 episodes (43.2%) cessation of the hunger strike occurred immediately after admission to the security ward, and in 14 episodes (37.9%) during hospital stay. In the refeed cases (n = 30), nutritional replenishment occurred orally, and in 25 (83.3%) micronutrients substitutions were made based on the recommendations. The gradual refeeding with fluid restriction occurred over 10 d. Uncomplicated dyselectrolytemia was documented in 12 cases (40%) within the refeeding phase. One case (3.3%) presented bilateral ankle edemas as a clinical manifestation of moderate RFS. Intensive medical treatment was not necessary and none of the patients died. Seven episodes of continued hunger strike were observed during the entire hospital stay without medical complications. Our data suggested that seriousness and rate of medical complications during the refeeding phase can be kept at a minimum in a hunger strike population. This study supported use of recommendations to optimize risk management and to improve treatment quality and patient safety in this vulnerable population. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluating the Effects of a Bird Strike Advisory System

NARCIS (Netherlands)

Metz, I.C.; Mühlhausen, T; Ellerbroek, J.; Hoekstra, J.M.

2016-01-01

Bird strikes have operational impacts and cause economic loss to the aviation industry. In the worst case, the damages resulting from bird strikes lead to crashes. The highest risk for bird strikes lies in the area below 3000 ft and thus mainly in airport environments. Despite intense efforts from

Debunking the viper's strike: harmless snakes kill a common assumption.

Science.gov (United States)

Penning, David A; Sawvel, Baxter; Moon, Brad R

2016-03-01

To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. © 2016 The Author(s).

Foot strike and injury rates in endurance runners: a retrospective study.

Science.gov (United States)

Daoud, Adam I; Geissler, Gary J; Wang, Frank; Saretsky, Jason; Daoud, Yahya A; Lieberman, Daniel E

2012-07-01

This retrospective study tests if runners who habitually forefoot strike have different rates of injury than runners who habitually rearfoot strike. We measured the strike characteristics of middle- and long-distance runners from a collegiate cross-country team and quantified their history of injury, including the incidence and rate of specific injuries, the severity of each injury, and the rate of mild, moderate, and severe injuries per mile run. Of the 52 runners studied, 36 (69%) primarily used a rearfoot strike and 16 (31%) primarily used a forefoot strike. Approximately 74% of runners experienced a moderate or severe injury each year, but those who habitually rearfoot strike had approximately twice the rate of repetitive stress injuries than individuals who habitually forefoot strike. Traumatic injury rates were not significantly different between the two groups. A generalized linear model showed that strike type, sex, race distance, and average miles per week each correlate significantly (P strike have significantly higher rates of repetitive stress injury than those who mostly forefoot strike. This study does not test the causal bases for this general difference. One hypothesis, which requires further research, is that the absence of a marked impact peak in the ground reaction force during a forefoot strike compared with a rearfoot strike may contribute to lower rates of injuries in habitual forefoot strikers.

effects of strike cost on economic development in nigeria

African Journals Online (AJOL)

USER

same firm, in other firms even in other industries (Kempner, 1980). For example ... The main purpose of this paper is to examine the strike cost and productivity in. Nigeria. ... Obnoxious Policies: Workers do go on strike when management makes obnoxious ... ASUU had to go on strike; the FGN had rescinded the decision.

Paleomagnetic and structural evidence for oblique slip in a fault-related fold, Grayback monocline, Colorado

Science.gov (United States)

Tetreault, J.; Jones, C.H.; Erslev, E.; Larson, S.; Hudson, M.; Holdaway, S.

2008-01-01

Significant fold-axis-parallel slip is accommodated in the folded strata of the Grayback monocline, northeastern Front Range, Colorado, without visible large strike-slip displacement on the fold surface. In many cases, oblique-slip deformation is partitioned; fold-axis-normal slip is accommodated within folds, and fold-axis-parallel slip is resolved onto adjacent strike-slip faults. Unlike partitioning strike-parallel slip onto adjacent strike-slip faults, fold-axis-parallel slip has deformed the forelimb of the Grayback monocline. Mean compressive paleostress orientations in the forelimb are deflected 15??-37?? clockwise from the regional paleostress orientation of the northeastern Front Range. Paleomagnetic directions from the Permian Ingleside Formation in the forelimb are rotated 16??-42?? clockwise about a bedding-normal axis relative to the North American Permian reference direction. The paleostress and paleomagnetic rotations increase with the bedding dip angle and decrease along strike toward the fold tip. These measurements allow for 50-120 m of fold-axis-parallel slip within the forelimb, depending on the kinematics of strike-slip shear. This resolved horizontal slip is nearly equal in magnitude to the ???180 m vertical throw across the fold. For 200 m of oblique-slip displacement (120 m of strike slip and 180 m of reverse slip), the true shortening direction across the fold is N90??E, indistinguishable from the regionally inferred direction of N90??E and quite different from the S53??E fold-normal direction. Recognition of this deformational style means that significant amounts of strike slip can be accommodated within folds without axis-parallel surficial faulting. ?? 2008 Geological Society of America.

Global medicine: Is it ethical or morally justifiable for doctors and other healthcare workers to go on strike?

Science.gov (United States)

2013-01-01

Background Doctor and healthcare worker (HCW) strikes are a global phenomenon with the potential to negatively impact on the quality of healthcare services and the doctor-patient relationship. Strikes are a legitimate deadlock breaking mechanism employed when labour negotiations have reached an impasse during collective bargaining. Striking doctors usually have a moral dilemma between adherence to the Hippocratic tenets of the medical profession and fiduciary obligation to patients. In such circumstances the ethical principles of respect for autonomy, justice and beneficence all come into conflict, whereby doctors struggle with their role as ordinary employees who are rightfully entitled to a just wage for just work versus their moral obligations to patients and society. Discussion It has been argued that to deny any group of workers, including "essential workers" the right to strike is akin to enslavement which is ethically and morally indefensible. While HCW strikes occur globally, the impact appears more severe in developing countries challenged by poorer socio-economic circumstances, embedded infrastructural deficiencies, and lack of viable alternative means of obtaining healthcare. These communities appear to satisfy the criteria for vulnerability and may be deserving of special ethical consideration when doctor and HCW strikes are contemplated. Summary The right to strike is considered a fundamental right whose derogation would be inimical to the proper functioning of employer/employee collective bargaining in democratic societies. Motivations for HCW strikes include the natural pressure to fulfil human needs and the paradigm shift in modern medical practice, from self-employment and benevolent paternalism, to managed healthcare and consumer rights. Minimizing the incidence and impact of HCW strikes will require an ethical approach from all stakeholders, and recognition that all parties have an equal moral obligation to serve the best interests of society

Global medicine: is it ethical or morally justifiable for doctors and other healthcare workers to go on strike?

Science.gov (United States)

Chima, Sylvester C

2013-01-01

Doctor and healthcare worker (HCW) strikes are a global phenomenon with the potential to negatively impact on the quality of healthcare services and the doctor-patient relationship. Strikes are a legitimate deadlock breaking mechanism employed when labour negotiations have reached an impasse during collective bargaining. Striking doctors usually have a moral dilemma between adherence to the Hippocratic tenets of the medical profession and fiduciary obligation to patients. In such circumstances the ethical principles of respect for autonomy, justice and beneficence all come into conflict, whereby doctors struggle with their role as ordinary employees who are rightfully entitled to a just wage for just work versus their moral obligations to patients and society. It has been argued that to deny any group of workers, including "essential workers" the right to strike is akin to enslavement which is ethically and morally indefensible. While HCW strikes occur globally, the impact appears more severe in developing countries challenged by poorer socio-economic circumstances, embedded infrastructural deficiencies, and lack of viable alternative means of obtaining healthcare. These communities appear to satisfy the criteria for vulnerability and may be deserving of special ethical consideration when doctor and HCW strikes are contemplated. The right to strike is considered a fundamental right whose derogation would be inimical to the proper functioning of employer/employee collective bargaining in democratic societies. Motivations for HCW strikes include the natural pressure to fulfil human needs and the paradigm shift in modern medical practice, from self-employment and benevolent paternalism, to managed healthcare and consumer rights. Minimizing the incidence and impact of HCW strikes will require an ethical approach from all stakeholders, and recognition that all parties have an equal moral obligation to serve the best interests of society. Employers should implement

Forward to the Past: Strikes and Striking as Dialogue by other ...

African Journals Online (AJOL)

In Nigeria, from the colonial period to the present, the employment of strikes and protests by nationalists, Nigerian workers and civil society groups has been established as one of the potent means of conveying viewpoints, positions as well as the demand for equality, fairness, social justice and reforms. It has been used as ...

Joint contact loading in forefoot and rearfoot strike patterns during running.

Science.gov (United States)

Rooney, Brandon D; Derrick, Timothy R

2013-09-03

Research concerning forefoot strike pattern (FFS) versus rearfoot strike pattern (RFS) running has focused on the ground reaction force even though internal joint contact forces are a more direct measure of the loads responsible for injury. The main purpose of this study was to determine the internal loading of the joints for each strike pattern. A secondary purpose was to determine if converted FFS and RFS runners can adequately represent habitual runners with regards to the internal joint loading. Using inverse dynamics to calculate the net joint moments and reaction forces and optimization techniques to estimate muscle forces, we determined the axial compressive loading at the ankle, knee, and hip. Subjects consisted of 15 habitual FFS and 15 habitual RFS competitive runners. Each subject ran at a preferred running velocity with their habitual strike pattern and then converted to the opposite strike pattern. Plantar flexor muscle forces and net ankle joint moments were greater in the FFS running compared to the RFS running during the first half of the stance phase. The average contact forces during this period increased by 41.7% at the ankle and 14.4% at the knee joint during FFS running. Peak ankle joint contact force was 1.5 body weights greater during FFS running (pstrike pattern. Copyright © 2013 Elsevier Ltd. All rights reserved.

Option Strike Price and Managerial Investment Decisions

Institute of Scientific and Technical Information of China (English)

刘鸿雁; 张维

2003-01-01

The manager′s investment decisions is modeled when the manager is risk-averse and has stock options as compensation. It is found that the strike price of options is crucial to the investment incentives of managers, and that the correct value, or interval of values, of managerial stock option strike price can bring stockholder and manager interests in agreement.

Effects of footwear and strike type on running economy.

Science.gov (United States)

Perl, Daniel P; Daoud, Adam I; Lieberman, Daniel E

2012-07-01

This study tests if running economy differs in minimal shoes versus standard running shoes with cushioned elevated heels and arch supports and in forefoot versus rearfoot strike gaits. We measured the cost of transport (mL O(2)·kg(-1)·m(-1)) in subjects who habitually run in minimal shoes or barefoot while they were running at 3.0 m·s(-1) on a treadmill during forefoot and rearfoot striking while wearing minimal and standard shoes, controlling for shoe mass and stride frequency. Force and kinematic data were collected when subjects were shod and barefoot to quantify differences in knee flexion, arch strain, plantar flexor force production, and Achilles tendon-triceps surae strain. After controlling for stride frequency and shoe mass, runners were 2.41% more economical in the minimal-shoe condition when forefoot striking and 3.32% more economical in the minimal-shoe condition when rearfoot striking (P forefoot and rearfoot striking did not differ significantly in cost for either minimal- or standard-shoe running. Arch strain was not measured in the shod condition but was significantly greater during forefoot than rearfoot striking when barefoot. Plantar flexor force output was significantly higher in forefoot than in rearfoot striking and in barefoot than in shod running. Achilles tendon-triceps surae strain and knee flexion were also lower in barefoot than in standard-shoe running. Minimally shod runners are modestly but significantly more economical than traditionally shod runners regardless of strike type, after controlling for shoe mass and stride frequency. The likely cause of this difference is more elastic energy storage and release in the lower extremity during minimal-shoe running.

The geometry of pull-apart basins in the southern part of Sumatran strike-slip fault zone

Science.gov (United States)

Aribowo, Sonny

2018-02-01

Models of pull-apart basin geometry have been described by many previous studies in a variety tectonic setting. 2D geometry of Ranau Lake represents a pull-apart basin in the Sumatran Fault Zone. However, there are unclear geomorphic traces of two sub-parallel overlapping strike-slip faults in the boundary of the lake. Nonetheless, clear geomorphic traces that parallel to Kumering Segment of the Sumatran Fault are considered as inactive faults in the southern side of the lake. I demonstrate the angular characteristics of the Ranau Lake and Suoh complex pull-apart basins and compare with pull-apart basin examples from published studies. I use digital elevation model (DEM) image to sketch the shape of the depression of Ranau Lake and Suoh Valley and measure 2D geometry of pull-apart basins. This study shows that Ranau Lake is not a pull-apart basin, and the pull-apart basin is actually located in the eastern side of the lake. Since there is a clear connection between pull-apart basin and volcanic activity in Sumatra, I also predict that the unclear trace of the pull-apart basin near Ranau Lake may be covered by Ranau Caldera and Seminung volcanic products.

Geomorphic Evidence of a Complex late-Cenozoic Uplift and Lateral Displacement History Along the 2013 M7.7 Baluchistan, Pakistan Strike-slip Rupture

Science.gov (United States)

Harbor, D. J.; Barnhart, W. D.

2017-12-01

The 2013 M7.7 Baluchistan earthquake in southern Pakistan ruptured 200 km of the north-dipping Hoshab reverse fault with dominantly lateral motion, clearly at odds with the regional topography created by previous reverse fault offsets. The kinematics of this earthquake led to the hypotheses that the Hoshab fault may alternatively slip in a reverse and lateral sense (bi-modal slip), and that the southeast Makran rotates as a uniform block around the fault (ball-and-socket rotation). Here, we use river profiles, regional relief, fault locations, and detailed geomorphic maps derived from optical imagery and DEMs to evaluate the recent uplift history of this region. We find that late Cenozoic fault zone geomorphology supports a spatially complex transition from lateral-dominated offsets in the NE to reverse-dominated offsets in the SW. Additionally, fault zone geomorphology suggests that the location of the Hoshab fault itself may change through time, leading to active incision of footwall alluvial fans and pediments. Stream profiles likewise record incision patterns that vary along the Hoshab fault. Incision and deposition in the SW are illustrative of relative footwall subsidence, consistent with recent uplift on the Hoshab fault; whereas incision and deposition in the NE are illustrative of relative footwall uplift consistent with ongoing regional uplift due to ball-and-socket rotations and dominantly lateral offsets along the northern Hoshab fault. The largest streams also record multiple, discrete, base-level drops, including the presence of convex-up river profiles in the hanging wall of the Hoshab fault. These profiles along hanging wall streams highlight a complex spatial and temporal history of reverse offset, lateral channel offset, and base-level resetting in regional streams that are altogether inconsistent with the kinematics of the 2013 earthquake alone, but that are consistent with the bi-modal slip model. Additionally, the evidence of footwall uplift in

Strike Point Control on EAST Using an Isoflux Control Method

International Nuclear Information System (INIS)

Xing Zhe; Xiao Bingjia; Luo Zhengping; Walker, M. L.; Humphreys, D. A.

2015-01-01

For the advanced tokamak, the particle deposition and thermal load on the divertor is a big challenge. By moving the strike points on divertor target plates, the position of particle deposition and thermal load can be shifted. We could adjust the Poloidal Field (PF) coil current to achieve the strike point position feedback control. Using isoflux control method, the strike point position can be controlled by controlling the X point position. On the basis of experimental data, we establish relational expressions between X point position and strike point position. Benchmark experiments are carried out to validate the correctness and robustness of the control methods. The strike point position is successfully controlled following our command in the EAST operation. (paper)

Comparison of force, power, and striking efficiency for a Kung Fu strike performed by novice and experienced practitioners: preliminary analysis.

Science.gov (United States)

Neto, Osmar Pinto; Magini, Marcio; Saba, Marcelo M F; Pacheco, Marcos Tadeu Tavares

2008-02-01

This paper presents a comparison of force, power, and efficiency values calculated from Kung Fu Yau-Man palm strikes, when performed by 7 experienced and 6 novice men. They performed 5 palm strikes to a freestanding basketball, recorded by high-speed camera at 1000 Hz. Nonparametric comparisons and correlations showed experienced practitioners presented larger values of mean muscle force, mean impact force, mean muscle power, mean impact power, and mean striking efficiency, as is noted in evidence obtained for other martial arts. Also, an interesting result was that for experienced Kung Fu practitioners, muscle power was linearly correlated with impact power (p = .98) but not for the novice practitioners (p = .46).

Preventive strike vs. false targets and protection in defense strategy

International Nuclear Information System (INIS)

Levitin, Gregory; Hausken, Kjell

2011-01-01

A defender allocates its resource between defending an object passively and striking preventively against an attacker seeking to destroy the object. With no preventive strike the defender distributes its entire resource between deploying false targets, which the attacker cannot distinguish from the genuine object, and protecting the object. If the defender strikes preventively, the attacker's vulnerability depends on its protection and on the defender's resource allocated to the strike. If the attacker survives, the object's vulnerability depends on the attacker's revenge attack resource allocated to the attacked object. The optimal defense resource distribution between striking preventively, deploying the false targets and protecting the object is analyzed. Two cases of the attacker strategy are considered: when the attacker attacks all of the targets and when it chooses a number of targets to attack. An optimization model is presented for making a decision about the efficiency of the preventive strike based on the estimated attack probability, dependent on a variety of model parameters.

WAVELET TRANSFORM ANALYSIS OF ELECTROMYOGRAPHY KUNG FU STRIKES DATA

Directory of Open Access Journals (Sweden)

Ana Carolina de Miranda Marzullo

2009-11-01

Full Text Available In martial arts and contact sports strikes are performed at near maximum speeds. For that reason, electromyography (EMG analysis of such movements is non-trivial. This paper has three main goals: firstly, to investigate the differences in the EMG activity of muscles during strikes performed with and without impacts; secondly, to assess the advantages of using Sum of Significant Power (SSP values instead of root mean square (rms values when analyzing EMG data; and lastly to introduce a new method of calculating median frequency values using wavelet transforms (WMDF. EMG data of the deltoid anterior (DA, triceps brachii (TB and brachioradialis (BR muscles were collected from eight Kung Fu practitioners during strikes performed with and without impacts. SSP results indicated significant higher muscle activity (p = 0.023 for the strikes with impact. WMDF results, on the other hand, indicated significant lower values (p = 0. 007 for the strikes with impact. SSP results presented higher sensitivity than rms to quantify important signal differences and, at the same time, presented lower inter-subject coefficient of variations. The result of increase in SSP values and decrease in WMDF may suggest better synchronization of motor units for the strikes with impact performed by the experienced Kung Fu practitioners

Review of the Lightning Strike Incident at Launch Complex 37 on July 27, 1967, and Comparison to a Gemini Lightning Strike

Science.gov (United States)

Llewellyn, J. A.

1967-01-01

The Launch Complex 37 lightning strike of July 27, 1967, was reviewed and compared to a similar incident on the Gemini Program. Available data indicate little likelihood of damaging currents having been present in SA-204 Launch Vehicle or the ground equipment during the July 27th incident. Based on the results of subsystem and system testing after the strike, anticipated results of future testing, the six months elapsed time between the strike-and launch, and the fact that much of the critical airborne electrical/electronic equipment has been removed since the strike for other reasons, no new actions are considered necessary at this time in the Gemini case, significant failures occurred in both airborne and ground circuits. Due to the resultant semi, condlictor uncertainty, and the relatively' short time prior to planned launch, all critical airborne components containing semiconduetors were replaced, and a sophisticated data comparison task was implemented.

ILO: Grev Hakkına İlişkin Kriz / ILO: Crisis in Terms of Right to Strike

Directory of Open Access Journals (Sweden)

Sevda KÖSE

2018-02-01

Full Text Available Bu çalışmanın amacı, 2012 yılında Uluslararası Çalışma Örgütü Konferansındaki işveren grubunun grev hakkı ile ilgili yaptığı sert itirazların Uluslararası Çalışma Örgütü (ILO bağlamında bir krize yol açıp açmadığının incelenmesidir. ILO ve denetim mekanizmaları aracılığı ile oluşturulan içtihatlar bağlamında 60 yıl boyunca grev hakkına, örgütlenme özgürlüğünün bir parçası olarak yer verilerek, toplu sözleşme, sendika hakkı ve grev hakkı bir bütün olarak düşünülmüştür. Bu içtihatların, grev hakkının uluslararası alanda tanınmasına olan katkısı fazladır. Bu durum ta ki 2012 yılındaki ILO Konferansı’na kadar devam etmiştir. İşveren grubundan ciddi bir itiraz ile birlikte grev hakkı ile ilgili ILO’da bir kriz olup olmadığı sorusu gündeme gelmeye başlamıştır. Bu durum ILO’nun denetim mekanizmasının etkinliğinin sorgulanmasına neden olurken aynı zamanda ILO’nun denetim organları içindeki eşgüdümün de eleştirilmesine yol açmıştır. / The purpose of this study is to examine whether the rigid objections made by the employers’ group at the International Labor Organization Conference in 2012 on the right to strike led to a crisis the context of the International Labor Organization. For sixty years in the context of jurispurudence of ILO’s superbody mechanicsm when it is thought that right to strike has been included as a part of freedom of association and at the same time, the right to collective bargaining, trade union rights and right to strike has been considered as a whole. This situation continued until 2012 ILO Conference. With a serious objection from the employers’ group, the question of whether there was a crisis in the ILO regarding the right to strike began to come to the fore. This led to the questioning of the effectiveness of the ILO’s superbody mechanism and at the same time the ILO’s criticism of its coordination

Analogue modelling on the interaction between shallow magma intrusion and a strike-slip fault: Application on the Middle Triassic Monzoni Intrusive Complex (Dolomites, Italy)

Science.gov (United States)

Michail, Maria; Coltorti, Massimo; Gianolla, Piero; Riva, Alberto; Rosenau, Matthias; Bonadiman, Costanza; Galland, Olivier; Guldstrand, Frank; Thordén Haug, Øystein; Rudolf, Michael; Schmiedel, Tobias

2017-04-01

The southwestern part of the Dolomites in Northern Italy has undergone a short-lived Ladinian (Middle Triassic) tectono-magmatic event, forming a series of significant magmatic features. These intrusive bodies deformed and metamorphosed the Permo-Triassic carbonate sedimentary framework. In this study we focus on the tectono-magmatic evolution of the shallow shoshonitic Monzoni Intrusive Complex of this Ladinian event (ca 237 Ma), covering an area of 20 km^2. This NW-SE elongated intrusive structure (5 km length) shows an orogenic magmatic affinity which is in contrast to the tectonic regime at the time of intrusion. Strain analysis shows anorogenic transtensional displacement in accordance with the ENE-WSW extensional pattern in the central Dolomites during the Ladinian. Field interpretations led to a detailed description of the regional stratigraphic sequence and the structural features of the study area. However, the geodynamic context of this magmatism and the influence of the inherited strike-slip fault on the intrusion, are still in question. To better understand the specific natural prototype and the general mechanisms of magma emplacement in tectonically active areas, we performed analogue experiments defined by, but not limited to, first order field observations. We have conducted a systematic series of experiments in different tectonic regimes (static conditions, strike-slip, transtension). We varied the ratio of viscous to brittle stresses between magma and country rock, by injecting Newtonian fluids both of high and low viscosity (i.e. silicone oil/vegetable oil) into granular materials of varying cohesion (sand, silica flour, glass beads). The evolving surface and side view of the experiments were monitored by photogrammetric techniques for strain analyses and topographic evolution. In our case, the combination of the results from field and analogue experiments brings new insights regarding the tectonic regime, the geometry of the intrusive body, and

The Teacher Strike: School District Protection Procedures. A Manual for School District Officials on How to Handle a Teachers' Strike.

Science.gov (United States)

Igoe, Joseph A.; DiRocco, Anthony P.

This booklet is designed to give practical and realistic advice to school district officials faced with the possibility of a teachers' strike. It is intended for use both by school district administrators and school board members. The booklet is organized into four sections that focus in turn on signs of a pending teachers' strike, union…

‘The Nairobi General Strike [1950]: from protest to insurgency’

OpenAIRE

Hyde, David

2002-01-01

The Nairobi General Strike [1950] was the culmination of Kenya’s post war strike wave and urban upheaval. An unprecedented upsurge occurred with the general strikes in Mombasa [1947] led by the African Workers Federation [A.W.F.] and in Nairobi by the East African Trades Union Congress [E.A.T.U.C.]. While this has been termed and treated as a city wide strike, there is enough evidence to suggest a movement that went some way beyond Nairobi. The extent of the cohesion and reciprocal impacts am...

Children on hunger strike: child abuse or legitimate protest?

OpenAIRE

Mok, A.; Nelson, E. A.; Murphy, J.; Hampson, A.; Hendriks, J. H.

1996-01-01

The issue of children on hunger strike (voluntary total fasting) has not been reported before. The World Medical Association Declaration of Tokyo 1975 and the Declaration of Malta 1991 (revised 1992) provide clinicians with guidelines for the management of adult patients on hunger strike but do not mention children. We report the management of 14 Vietnamese children, aged 1 to 12 years, who took part in a hunger strike at a refugee detention centre in Hong Kong.

Expertise of using striking techniques for power stroke in badminton.

Science.gov (United States)

Zhu, Qin

2013-10-01

Two striking techniques (fast swing and angled striking) were examined to see if they allowed effective use of string tension for the power stroke in badminton. 12 participants (4 novices, 4 recreational, and 4 expert badminton players) were recorded by a fast-speed camera while striking a shuttlecock with racquets of 8 different string tensions. The peak speed of the shuttlecock, the racquet angle and the shuttlecock angle were analyzed. The results showed that expert players succeeded in using both striking techniques to overcome the constraint of string tension and produce a consistently superior stroke. Failure to use either striking technique resulted in inferior performance that was constrained by string tension. Expertise in badminton allows the necessary motor adjustments based on the affordance perception of the string tension.

Developing personal values: trainees' attitudes toward strikes by health care providers.

Science.gov (United States)

Li, Su-Ting T; Srinivasan, Malathi; Der-Martirosian, Claudia; Kravitz, Richard L; Wilkes, Michael S

2011-05-01

Worldwide, health care providers use strikes and job actions to influence policy. For health care providers, especially physicians, strikes create an ethical tension between an obligation to care for current patients (e.g., to provide care and avoid abandonment) and an obligation to better care for future patients by seeking system improvements (e.g., improvements in safety, to access, and in the composition and strength of the health care workforce). This tension is further intensified when the potential benefit of a strike involves professional self-interest and the potential risk involves patient harm or death. By definition, trainees are still forming their professional identities and values, including their opinions on fair wages, health policy, employee benefits, professionalism, and strikes. In this article, the authors explore these ethical tensions, beginning with a discussion of reactions to a potential 2005 nursing strike at the University of California, Davis, Medical Center. The authors then propose a conceptual model describing factors that may influence health care providers' decisions to strike (including personal ethics, personal agency, and strike-related context). In particular, the authors explore the relationship between training level and attitudes toward taking a job action, such as going on strike. Because trainees' attitudes toward strikes continue to evolve during training, the authors maintain that open discussion around the ethics of health care professionals' strikes and other methods of conflict resolution should be included in medical education to enhance professionalism and systems-based practice training. The authors include sample case vignettes to help initiate these important discussions. Copyright © by the Association of American medical Colleges.

Impact of lightning strikes on hospital functions.

Science.gov (United States)

Mortelmans, Luc J M; Van Springel, Gert L J; Van Boxstael, Sam; Herrijgers, Jan; Hoflacks, Stefaan

2009-01-01

Two regional hospitals were struck by lightning during a one-month period. The first hospital, which had 236 beds, suffered a direct strike to the building. This resulted in a direct spread of the power peak and temporary failure of the standard power supply. The principle problems, after restoring standard power supply, were with the fire alarm system and peripheral network connections in the digital radiology systems. No direct impact on the hardware could be found. Restarting the servers resolved all problems. The second hospital, which had 436 beds, had a lightning strike on the premises and mainly experienced problems due to induction. All affected installations had a cable connection from outside in one way or another. The power supplies never were endangered. The main problem was the failure of different communication systems (telephone, radio, intercom, fire alarm system). Also, the electronic entrance control went out. During the days after the lightening strike, multiple software problems became apparent, as well as failures of the network connections controlling the technical support systems. There are very few ways to prepare for induction problems. The use of fiber-optic networks can limit damage. To the knowledge of the authors, these are the first cases of lightning striking hospitals in medical literature.

Near N-S paleo-extension in the western Deccan region, India: Does it link strike-slip tectonics with India-Seychelles rifting?

Science.gov (United States)

Misra, Achyuta Ayan; Bhattacharya, Gourab; Mukherjee, Soumyajit; Bose, Narayan

2014-09-01

This is the first detailed report and analyses of deformation from the W part of the Deccan large igneous province (DLIP), Maharashtra, India. This deformation, related to the India-Seychelles rifting during Late Cretaceous-Early Paleocene, was studied, and the paleostress tensors were deduced. Near N-S trending shear zones, lineaments, and faults were already reported without significant detail. An E-W extension was envisaged by the previous workers to explain the India-Seychelles rift at ~64 Ma. The direction of extension, however, does not match with their N-S brittle shear zones and also those faults (sub-vertical, ~NE-SW/~NW-SE, and few ~N-S) we report and emphasize in this work. Slickenside-bearing fault planes, brittle shear zones, and extension fractures in meso-scale enabled us to estimate the paleostress tensors (directions and relative magnitudes). The field study was complemented by remote sensing lineament analyses to map dykes and shear zones. Dykes emplaced along pre-existing ~N-S to ~NE-SW/~NW-SE shears/fractures. This information was used to derive regional paleostress trends. A ~NW-SE/NE-SW minimum compressive stress in the oldest Kalsubai Subgroup and a ~N-S direction for the younger Lonavala, Wai, and Salsette Subgroups were deciphered. Thus, a ~NW/NE to ~N-S extension is put forward that refutes the popular view of E-W India-Seychelles extension. Paleostress analyses indicate that this is an oblique rifted margin. Field criteria suggest only ~NE-SW and ~NW-SE, with some ~N-S strike-slip faults/brittle shear zones. We refer this deformation zone as the "Western Deccan Strike-slip Zone" (WDSZ). The observed deformation was matched with offshore tectonics deciphered mainly from faults interpreted on seismic profiles and from magnetic seafloor spreading anomalies. These geophysical findings too indicate oblique rifting in this part of the W Indian passive margin. We argue that the Seychelles microcontinent separated from India only after much of

Strike kinematics and performance in juvenile ball pythons (Python regius).

Science.gov (United States)

Ryerson, William G; Tan, Weimin

2017-08-01

The rapid strike of snakes has interested researchers for decades. Although most work has focused on the strike performance of vipers, recent work has shown that other snakes outside of the Viperidae can strike with the same velocities and accelerations. However, to date all of these examples focus on performance in adult snakes. Here, we use high-speed video to measure the strike kinematics and performance of 10 juvenile (pythons, Python regius. We find that juvenile P. regius strike at levels comparable to larger snakes, but with shorter durations and over shorter distances. We conclude that the juvenile P. regius maintain performance likely through manipulation of the axial musculature and accompanying elastic tissues, and that this is a first step to understanding ontogenetic changes in behavior and a potential avenue for understanding how captivity may also impact behavior. © 2017 Wiley Periodicals, Inc.

effect of strikes on management and planning of educational ...

African Journals Online (AJOL)

Global Journal

Strike is an event that consumes and waste a lot of time which implies that ... from this paper. KEYWORDS: Strikes, Management, Planning, Educational, Activities, Universities ..... employers; and Introduction of new technology which affect the ...

Acute changes in foot strike pattern and cadence affect running parameters associated with tibial stress fractures.

Science.gov (United States)

Yong, Jennifer R; Silder, Amy; Montgomery, Kate L; Fredericson, Michael; Delp, Scott L

2018-05-18

Tibial stress fractures are a common and debilitating injury that occur in distance runners. Runners may be able to decrease tibial stress fracture risk by adopting a running pattern that reduces biomechanical parameters associated with a history of tibial stress fracture. The purpose of this study was to test the hypothesis that converting to a forefoot striking pattern or increasing cadence without focusing on changing foot strike type would reduce injury risk parameters in recreational runners. Running kinematics, ground reaction forces and tibial accelerations were recorded from seventeen healthy, habitual rearfoot striking runners while running in their natural running pattern and after two acute retraining conditions: (1) converting to forefoot striking without focusing on cadence and (2) increasing cadence without focusing on foot strike. We found that converting to forefoot striking decreased two risk factors for tibial stress fracture: average and peak loading rates. Increasing cadence decreased one risk factor: peak hip adduction angle. Our results demonstrate that acute adaptation to forefoot striking reduces different injury risk parameters than acute adaptation to increased cadence and suggest that both modifications may reduce the risk of tibial stress fractures. Copyright © 2018 Elsevier Ltd. All rights reserved.

Kinematic Analysis of Fault-Slip Data in the Central Range of Papua, Indonesia

Directory of Open Access Journals (Sweden)

Benyamin Sapiie

2016-01-01

Full Text Available DOI:10.17014/ijog.3.1.1-16Most of the Cenozoic tectonic evolution in New Guinea is a result of obliquely convergent motion that ledto an arc-continent collision between the Australian and Pacific Plates. The Gunung Bijih (Ertsberg Mining District(GBMD is located in the Central Range of Papua, in the western half of the island of New Guinea. This study presentsthe results of detailed structural mapping concentrated on analyzing fault-slip data along a 15-km traverse of theHeavy Equipment Access Trail (HEAT and the Grasberg mine access road, providing new information concerning thedeformation in the GBMD and the Cenozoic structural evolution of the Central Range. Structural analysis indicatesthat two distinct stages of deformation have occurred since ~12 Ma. The first stage generated a series of en-echelonNW-trending (π-fold axis = 300° folds and a few reverse faults. The second stage resulted in a significant left-lateralstrike-slip faulting sub-parallel to the regional strike of upturned bedding. Kinematic analysis reveals that the areasbetween the major strike-slip faults form structural domains that are remarkably uniform in character. The changein deformation styles from contractional to a strike-slip offset is explained as a result from a change in the relativeplate motion between the Pacific and Australian Plates at ~4 Ma. From ~4 - 2 Ma, transform motion along an ~ 270°trend caused a left-lateral strike-slip offset, and reactivated portions of pre-existing reverse faults. This action had aprofound effect on magma emplacement and hydrothermal activity.

When strike comes to town... anticipated and actual behavioural reactions to a one-day, pre-announced, complete rail strike in the Netherlands

NARCIS (Netherlands)

Rietveld, P.; Exel, N.J.A.

2009-01-01

We conducted secondary analysis on data collected among rail users, days before and after a national rail strike in the Netherlands. Our aim was to compare anticipated and actual behavioural reactions to the rail strike, investigate associations with traveller and trip characteristics, and perceived

Continental United States Hurricane Strikes

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Continental U.S. Hurricane Strikes Poster is our most popular poster which is updated annually. The poster includes all hurricanes that affected the U.S. since...

Is the rearfoot pattern the most frequently foot strike pattern among recreational shod distance runners?

Science.gov (United States)

de Almeida, Matheus Oliveira; Saragiotto, Bruno Tirotti; Yamato, Tiê Parma; Lopes, Alexandre Dias

2015-02-01

To determine the distribution of the foot strike patterns among recreational shod runners and to compare the personal and training characteristics between runners with different foot strike patterns. Cross-sectional study. Areas of running practice in São Paulo, Brazil. 514 recreational shod runners older than 18 years and free of injury. Foot strike patterns were evaluated with a high-speed camera (250 Hz) and photocells to assess the running speed of participants. Personal and training characteristics were collected through a questionnaire. The inter-rater reliability of the visual foot strike pattern classification method was 96.7% and intra-rater reliability was 98.9%. 95.1% (n = 489) of the participants were rearfoot strikers, 4.1% (n = 21) were midfoot strikers, and four runners (0.8%) were forefoot strikers. There were no significant differences between strike patterns for personal and training characteristics. This is the first study to demonstrate that almost all recreational shod runners were rearfoot strikers. The visual method of evaluation seems to be a reliable and feasible option to classify foot strike pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.

Miners' strike 1984-85

Energy Technology Data Exchange (ETDEWEB)

Brown, L; Salter, S [comps.

1985-01-01

References relating to the 1984-85 UK miners strike are listed under the following subject headings: events and analysis - a chronological record; short term effects - coal stocks and supplies, electricity supplies, financial, industrial and economic; the miners and their leadership; social aspects - civil liberties, media coverage, mining communities, picketing, policing, the future; pit closures. 240 references.

Influence of slip-surface geometry on earth-flow deformation, Montaguto earth flow, southern Italy

Science.gov (United States)

Guerriero, L.; Coe, Jeffrey A.; Revellio, P.; Grelle, G.; Pinto, F.; Guadagno, F.

2016-01-01

We investigated relations between slip-surface geometry and deformational structures and hydrologic features at the Montaguto earth flow in southern Italy between 1954 and 2010. We used 25 boreholes, 15 static cone-penetration tests, and 22 shallow-seismic profiles to define the geometry of basal- and lateral-slip surfaces; and 9 multitemporal maps to quantify the spatial and temporal distribution of normal faults, thrust faults, back-tilted surfaces, strike-slip faults, flank ridges, folds, ponds, and springs. We infer that the slip surface is a repeating series of steeply sloping surfaces (risers) and gently sloping surfaces (treads). Stretching of earth-flow material created normal faults at risers, and shortening of earth-flow material created thrust faults, back-tilted surfaces, and ponds at treads. Individual pairs of risers and treads formed quasi-discrete kinematic zones within the earth flow that operated in unison to transmit pulses of sediment along the length of the flow. The locations of strike-slip faults, flank ridges, and folds were not controlled by basal-slip surface topography but were instead dependent on earth-flow volume and lateral changes in the direction of the earth-flow travel path. The earth-flow travel path was strongly influenced by inactive earth-flow deposits and pre-earth-flow drainages whose positions were determined by tectonic structures. The implications of our results that may be applicable to other earth flows are that structures with strikes normal to the direction of earth-flow motion (e.g., normal faults and thrust faults) can be used as a guide to the geometry of basal-slip surfaces, but that depths to the slip surface (i.e., the thickness of an earth flow) will vary as sediment pulses are transmitted through a flow.

Midtarsal locking, the windlass mechanism, and running strike pattern: A kinematic and kinetic assessment.

Science.gov (United States)

Bruening, Dustin A; Pohl, Michael B; Takahashi, Kota Z; Barrios, Joaquin A

2018-05-17

Changes in running strike pattern affect ankle and knee mechanics, but little is known about the influence of strike pattern on the joints distal to the ankle. The purpose of this study was to explore the effects of forefoot strike (FFS) and rearfoot strike (RFS) running patterns on foot kinematics and kinetics, from the perspectives of the midtarsal locking theory and the windlass mechanism. Per the midtarsal locking theory, we hypothesized that the ankle would be more inverted in early stance when using a FFS, resulting in decreased midtarsal joint excursions and increased dynamic stiffness. Associated with a more engaged windlass mechanism, we hypothesized that a FFS would elicit increased metatarsophalangeal joint excursions and negative work in late stance. Eighteen healthy female runners ran overground with both FFS and RFS patterns. Instrumented motion capture and a validated multi-segment foot model were used to analyze midtarsal and metatarsophalangeal joint kinematics and kinetics. During early stance in FFS the ankle was more inverted, with concurrently decreased midtarsal eversion (p strike pattern during running. However, the windlass mechanism appeared to be engaged to a greater extent during FFS. Copyright © 2018 Elsevier Ltd. All rights reserved.

Variation in foot strike patterns during running among habitually barefoot populations.

Science.gov (United States)

Hatala, Kevin G; Dingwall, Heather L; Wunderlich, Roshna E; Richmond, Brian G

2013-01-01

Endurance running may have a long evolutionary history in the hominin clade but it was not until very recently that humans ran wearing shoes. Research on modern habitually unshod runners has suggested that they utilize a different biomechanical strategy than runners who wear shoes, namely that barefoot runners typically use a forefoot strike in order to avoid generating the high impact forces that would be experienced if they were to strike the ground with their heels first. This finding suggests that our habitually unshod ancestors may have run in a similar way. However, this research was conducted on a single population and we know little about variation in running form among habitually barefoot people, including the effects of running speed, which has been shown to affect strike patterns in shod runners. Here, we present the results of our investigation into the selection of running foot strike patterns among another modern habitually unshod group, the Daasanach of northern Kenya. Data were collected from 38 consenting adults as they ran along a trackway with a plantar pressure pad placed midway along its length. Subjects ran at self-selected endurance running and sprinting speeds. Our data support the hypothesis that a forefoot strike reduces the magnitude of impact loading, but the majority of subjects instead used a rearfoot strike at endurance running speeds. Their percentages of midfoot and forefoot strikes increased significantly with speed. These results indicate that not all habitually barefoot people prefer running with a forefoot strike, and suggest that other factors such as running speed, training level, substrate mechanical properties, running distance, and running frequency, influence the selection of foot strike patterns.

Variation in foot strike patterns during running among habitually barefoot populations.

Directory of Open Access Journals (Sweden)

Kevin G Hatala

Full Text Available Endurance running may have a long evolutionary history in the hominin clade but it was not until very recently that humans ran wearing shoes. Research on modern habitually unshod runners has suggested that they utilize a different biomechanical strategy than runners who wear shoes, namely that barefoot runners typically use a forefoot strike in order to avoid generating the high impact forces that would be experienced if they were to strike the ground with their heels first. This finding suggests that our habitually unshod ancestors may have run in a similar way. However, this research was conducted on a single population and we know little about variation in running form among habitually barefoot people, including the effects of running speed, which has been shown to affect strike patterns in shod runners. Here, we present the results of our investigation into the selection of running foot strike patterns among another modern habitually unshod group, the Daasanach of northern Kenya. Data were collected from 38 consenting adults as they ran along a trackway with a plantar pressure pad placed midway along its length. Subjects ran at self-selected endurance running and sprinting speeds. Our data support the hypothesis that a forefoot strike reduces the magnitude of impact loading, but the majority of subjects instead used a rearfoot strike at endurance running speeds. Their percentages of midfoot and forefoot strikes increased significantly with speed. These results indicate that not all habitually barefoot people prefer running with a forefoot strike, and suggest that other factors such as running speed, training level, substrate mechanical properties, running distance, and running frequency, influence the selection of foot strike patterns.

Foot strike pattern in children during shod-unshod running.

Science.gov (United States)

Latorre Román, Pedro Ángel; Balboa, Fernando Redondo; Pinillos, Felipe García

2017-10-01

The purpose of this study was to determine the foot strike patterns (FSPs) and neutral support (no INV/EVE and no foot rotation) in children, as well as to determine the influence of shod/unshod conditions and sex. A total of 713 children, aged 6 to 16 years, participated in this study (Age=10.28±2.71years, body mass index [BMI]=19.70±3.91kg/m 2 , 302 girls and 411 boys). A sagittal and frontal-plane video (240Hz) was recorded using a high-speed camcorder, to record the following variables: rearfoot strike (RFS), midfoot strike (MFS), forefoot strike (FFS), inversion/eversion (INV/EVE) and foot rotation on initial contact. RFS prevalence was similar between boys and girls in both shod and unshod conditions. In the unshod condition there was a significant reduction (p<0.001) of RFS prevalence both in boys (shod condition=83.95% vs. 62.65% unshod condition) and in girls (shod condition=87.85% vs. 62.70% unshod condition). No significant differences were found in INV/EVE and foot rotation between sex groups. In the unshod condition there was a significant increase (p<0.001) of neutral support (no INV/EVE) both in boys (shod condition=12.55% vs. 22.22% unshod condition) and in girls (shod condition=17.9% vs. 28.15% unshod condition). In addition, in the unshod condition there is a significant reduction (p<0.001) of neutral support (no foot rotation) both in boys (shod condition=21.55% vs. 11.10% unshod condition) and in girls (shod condition=21.05% vs. 11.95% unshod condition). In children, RFS prevalence is lower than adult's population. Additionally, barefoot running reduced the prevalence of RFS and INV/EVE, however increased foot rotation. Copyright © 2017 Elsevier B.V. All rights reserved.

Algab õppus "Saber Strike"

Index Scriptorium Estoniae

2014-01-01

Täna algab Eestis, Lätis ja Leedus Ameerika Ühendriikide Euroopa väekoondise õppus "Saber Strike", mille eesmärk on maaväeüksuste koostöö harjutamine. Õppusest võtab osa üle 2000 kaitseväelase Baltimaadest, USAst, Ühendkuningriigist, Taanist, Norrast, Soomest ja Saksamaalt. Eestist osaleb õppusel ligi 400 kaitseväelast

Central hyperadrenergic state after lightning strike.

Science.gov (United States)

Parsaik, Ajay K; Ahlskog, J Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H; Seime, Richard J; Craft, Jennifer M; Staab, Jeffrey P; Kantor, Birgit; Low, Phillip A

2013-08-01

To describe and review autonomic complications of lightning strike. Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation was highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the central nervous system or a secondary response is open to speculation.

VARIATION OF STRIKE INCENTIVES WITH DAMAGE PREFERENCES; FINAL

International Nuclear Information System (INIS)

G. CANAVAN

2001-01-01

For START III level forces, strike allocations and magnitudes vary little with L, but first strike costs vary directly with L, which means that for K reflecting a preference for the survival of high value targets over their destruction and a preference for high value over military targets, the costs of action are far greater than those of inaction for a wide range of values of damage preference L. Thus, if both sides have much greater preferences for the survival of their high value targets than for military targets or destruction, they do not see a net incentive to strike, and crises are terminated by inaction. Recent decades suggest strong preferences for the survival of high value and that this has contributed to the lack of direct conflict during that period

Seismically-triggered soft-sediment deformation structures close to a major strike-slip fault system in the Eastern Alps (Hirlatz cave, Austria)

Science.gov (United States)

Salomon, Martina Lan; Grasemann, Bernhard; Plan, Lukas; Gier, Susanne; Schöpfer, Martin P. J.

2018-05-01

We investigate episodic soft-sediment deformation structures cross-cut by normal faults preserved in unlithified finely laminated calcite rich sediments in the Hirlatz cave in the Northern Calcareous Alps (Austria). These sediments comprise varve-like alternations of brighter carbonate/quartz rich layers, and darker clay mineral rich layers. The deformed sediments contain abundant millimeter to centimeter-scale soft-sediment structures (load casts, ball-and-pillow structures), sheet slumps (thrust faults and folds), erosive channels filled with slides and chaotic slumps. After deposition and soft-sediment deformation normal faults developed within the entire sedimentary succession, an event that probably correlates with an offset of c. 10 cm of the passage wall above the outcrop. Our major conclusions are: (i) The sediments have a glacial origin and were deposited in the Hirlatz cave under phreatic fluvio-lacustrine conditions. The deposition and the soft-sediment deformation occurred most likely during the last glaciation (i.e. around 25 ka ago); (ii) The liquefaction and formation of the soft-sediment structures in water-saturated stratified layers was triggered by episodic seismic events; (iii) The internally deformed sediments were later displaced by normal faults; (iv) A possible source for the seismic events is the active sinistral Salzach-Ennstal-Mariazeller-Puchberger (SEMP) strike-slip fault which is located about 10 km south of the outcrop and plays a major role in accommodating the extrusion of the Eastern Alps towards the Pannonian Basin. To our knowledge, the described structures are the first report of liquefaction and seismically induced soft-sediment deformations in Quaternary sediments in the Eastern Alps.

Causes of falls of hangingwall over gullies adjacent to stabilizing strike pillars

CSIR Research Space (South Africa)

Turner, PA

1987-08-01

Full Text Available This report discusses the occurrence of falls of ground in strike gullies. Falls of hangingwall over strike gullies on the up-dip side of strike stabilizing pillars in longwall mining systems were investigated. Gullies were examined in both...

["Bell-striking" Saying of Acupuncture Therapy].

Science.gov (United States)

Zhao, Jing-Sheng

2017-04-25

As an analogy, a prototype of "bell-striking" is proposed in the present paper for exploring the basic properties, major elements, and potential mechanisms of acupuncture stimulation. On the strength of analysis on the physiological basis of acupuncture effect, several fundamental aspects of acupuncture are summarized as a) the body-surface stimulating characters, b) general and local effects, and c) triggering the auto-regulative function of the organism, which mimics the "bell-striking" response. Namely, when stroke, bell will chime, otherwise, chiming will not be heard. During analyzing special contents of acupuncture theory, its formative background should not be separated, and it is improper to take, modern medical theory of the human body as the guiding thinking way for researching the ancient Chinese medical literature.

Effect of Forefoot Strike on Lower Extremity Muscle Activity and Knee Joint Angle During Cutting in Female Team Handball Players.

Science.gov (United States)

Yoshida, Naruto; Kunugi, Shun; Mashimo, Sonoko; Okuma, Yoshihiro; Masunari, Akihiko; Miyazaki, Shogo; Hisajima, Tatsuya; Miyakawa, Shumpei

2015-06-01

The purpose of this study is to examine the effects of different strike forms, during cutting, on knee joint angle and lower limb muscle activity. Surface electromyography was used to measure muscle activity in individuals performing cutting manoeuvres involving either rearfoot strikes (RFS) or forefoot strikes (FFS). Three-dimensional motion analysis was used to calculate changes in knee angles, during cutting, and to determine the relationship between muscle activity and knee joint angle. Force plates were synchronized with electromyography measurements to compare muscle activity immediately before and after foot strike. The valgus angle tends to be smaller during FFS cutting than during RFS cutting. Just prior to ground contact, biceps femoris, semitendinosus, and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was greater during RFS cutting. Immediately after ground contact, biceps femoris and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was significantly lower during FFS cutting. The results of the present study suggest that the hamstrings demonstrate greater activity, immediately after foot strike, during FFS cutting than during RFS cutting. Thus, FFS cutting may involve a lower risk of anterior cruciate ligament injury than does RFS cutting.

Effect of basement structure and salt tectonics on deformation styles along strike: An example from the Kuqa fold-thrust belt, West China

Science.gov (United States)

Neng, Yuan; Xie, Huiwen; Yin, Hongwei; Li, Yong; Wang, Wei

2018-04-01

The Kuqa fold-thrust belt (KFTB) has a complex thrust-system geometry and comprises basement-involved thrusts, décollement thrusts, triangle zones, strike-slip faults, transpressional faults, and pop-up structures. These structures, combined with the effects of Paleogene salt tectonics and Paleozoic basement uplift form a complex structural zone trending E-W. Interpretation and comprehensive analysis of recent high-quality seismic data, field observations, boreholes, and gravity data covering the KFTB has been performed to understand the characteristics and mechanisms of the deformation styles along strike. Regional sections, fold-thrust system maps of the surface and the sub-salt layer, salt and basement structure distribution maps have been created, and a comprehensive analysis of thrust systems performed. The results indicate that the thrust-fold system in Paleogene salt range can be divided into five segments from east to west: the Kela-3, Keshen, Dabei, Bozi, and Awate segments. In the easternmost and westernmost parts of the Paleogene salt range, strike-slip faulting and basement-involved thrusting are the dominant deformation styles, as basement uplift and the limits of the Cenozoic evaporite deposit are the main controls on deformation. Salt-core detachment fold-thrust systems coincide with areas of salt tectonics, and pop-up, imbricate, and duplex structures are associated with the main thrust faults in the sub-salt layer. Distribution maps of thrust systems, basement structures, and salt tectonics show that Paleozoic basement uplift controlled the Paleozoic foreland basin morphology and the distribution of Cenozoic salt in the KFTB, and thus had a strong influence on the segmented structural deformation and evolution of the fold-thrust belt. Three types of transfer zone are identified, based on the characteristics of the salt layer and basement uplift, and the effects of these zones on the fault systems are evaluated. Basement uplift and the boundary of

THE EFFECT OF STEP RATE MANIPULATION ON FOOT STRIKE PATTERN OF LONG DISTANCE RUNNERS.

Science.gov (United States)

Allen, Darrell J; Heisler, Hollie; Mooney, Jennifer; Kring, Richard

2016-02-01

Running gait retraining to change foot strike pattern in runners from a heel strike pattern to a non heel- strike pattern has been shown to reduce impact forces and may help to reduce running related injuries. Step rate manipulation above preferred is known to help decrease step length, foot inclination angle, and vertical mass excursion, but has not yet been evaluated as a method to change foot strike pattern. The purpose of this study was to investigate the effect of step rate manipulation on foot strike pattern in shod recreational runners who run with a heel strike pattern. A secondary purpose was to describe the effect of step rate manipulation at specific percentages above preferred on foot inclination angle at initial contact. Forty volunteer runners, who were self-reported heel strikers and had a weekly running mileage of at least 10 miles, were recruited. Runners were confirmed to be heel strikers during the warm up period on the treadmill. The subject's step rate was determined at their preferred running pace. A metronome was used to increase step rate above the preferred step rate by 5%, 10% and 15%. 2D video motion analysis was utilized to determine foot strike pattern and to measure foot inclination angle at initial contact for each step rate condition. There was a statistically significant change in foot strike pattern from a heel strike pattern to a mid-foot or forefoot strike pattern at both 10% and 15% step rates above preferred. Seven of the 40 subjects (17.5%) changed from a heel- strike pattern to a non- heel strike pattern at +10% and 12 of the 40 subjects (30%) changed to a non-heel strike pattern at +15%. Mean foot inclination angle at initial contact showed a statistically significant change (reduction) as step rate increased. Step rate manipulation of 10% or greater may be enough to change foot strike pattern from a heel strike to a mid-foot or forefoot strike pattern in a small percentage of recreational runners who run in traditional

Stress sensitivity of fault seismicity: A comparison between limited-offset oblique and major strike-slip faults

Science.gov (United States)

Parsons, T.; Stein, R.S.; Simpson, R.W.; Reasenberg, P.A.

1999-01-01

We present a new three-dimensional inventory of the southern San Francisco Bay area faults and use it to calculate stress applied principally by the 1989 M = 7.1 Loma Prieta earthquake and to compare fault seismicity rates before and after 1989. The major high-angle right-lateral faults exhibit a different response to the stress change than do minor oblique (right-lateral/thrust) faults. Seismicity on oblique-slip faults in the southern Santa Clara Valley thrust belt increased where the faults were unclamped. The strong dependence of seismicity change on normal stress change implies a high coefficient of static friction. In contrast, we observe that faults with significant offset (>50-100 km) behave differently; microseismicity on the Hayward fault diminished where right-lateral shear stress was reduced and where it was unclamped by the Loma Prieta earthquake. We observe a similar response on the San Andreas fault zone in southern California after the Landers earthquake sequence. Additionally, the offshore San Gregorio fault shows a seismicity rate increase where right-lateral/oblique shear stress was increased by the Loma Prieta earthquake despite also being clamped by it. These responses are consistent with either a low coefficient of static friction or high pore fluid pressures within the fault zones. We can explain the different behavior of the two styles of faults if those with large cumulative offset become impermeable through gouge buildup; coseismically pressurized pore fluids could be trapped and negate imposed normal stress changes, whereas in more limited offset faults, fluids could rapidly escape. The difference in behavior between minor and major faults may explain why frictional failure criteria that apply intermediate coefficients of static friction can be effective in describing the broad distributions of aftershocks that follow large earthquakes, since many of these events occur both inside and outside major fault zones.

Manipulation of Foot Strike and Footwear Increases Achilles Tendon Loading During Running.

Science.gov (United States)

Rice, Hannah; Patel, Mubarak

2017-08-01

The Achilles tendon is the most common site of tendon overuse injury in humans. Running with a forefoot strike pattern and in minimal shoes is a topic of recent interest, yet evidence is currently limited regarding the combined influence of foot strike and footwear on Achilles tendon loading. To investigate the influence of both foot strike and footwear on Achilles tendon loading in habitual rearfoot strike runners. Controlled laboratory study. Synchronized kinematic and force data were collected from 22 habitual rearfoot strikers (11 male), who habitually ran in nonminimal running shoes, during overground running at 3.6 m·s -1 . Participants ran in 3 different footwear conditions (standard running shoe, minimal running shoe, and barefoot) with both a rearfoot strike (RFS) and an imposed forefoot strike (FFS) in each footwear condition. Achilles tendon loading was estimated by use of inverse dynamics, where the Achilles tendon moment arm was determined with a regression equation. A 2-way, repeated-measures analysis of variance was used to compare conditions. Achilles tendon impulse was greater when subjects ran with an FFS rather than an RFS in minimal shoes. Achilles tendon loading rates were higher when subjects ran either in minimal shoes or barefoot than in standard shoes, regardless of foot strike. In runners who habitually rearfoot strike in standard running shoes, running in minimal shoes or barefoot increased the rate of tendon loading, and running with a forefoot strike in minimal shoes increased the magnitude of tendon loading. Transitioning to these running conditions may increase the risk of tendinopathy.

Precision Strike Training in Lean Manufacturing: A Workplace Literacy Guidebook [and] Final Report on Precision Strike Workplace Literacy Training at CertainTeed Corporation.

Science.gov (United States)

National Alliance of Business, Inc., Washington, DC.

CertainTeed's Precision Strike training program was designed to close the gaps between the current status of its workplace and where that work force needed to be to compete successfully in global markets. Precision Strike included Skills and Knowledge in Lifelong Learning (SKILL) customized, computerized lessons in basic skills, one-on-one…

Effects of Foot Strike and Step Frequency on Achilles Tendon Stress During Running.

Science.gov (United States)

Lyght, Michael; Nockerts, Matthew; Kernozek, Thomas W; Ragan, Robert

2016-08-01

Achilles tendon (AT) injuries are common in runners. The AT withstands high magnitudes of stress during running which may contribute to injury. Our purpose was to examine the effects of foot strike pattern and step frequency on AT stress and strain during running utilizing muscle forces based on a musculoskeletal model and subject-specific ultrasound-derived AT cross-sectional area. Nineteen female runners performed running trials under 6 conditions, including rearfoot strike and forefoot strike patterns at their preferred cadence, +5%, and -5% preferred cadence. Rearfoot strike patterns had less peak AT stress (P forefoot strike pattern. A reduction in peak AT stress and strain were exhibited with a +5% preferred step frequency relative to the preferred condition using a rearfoot (P forefoot (P=.005) strike pattern. Strain rate was not different (P > .05) between step frequencies within each foot strike condition. Our results suggest that a rearfoot pattern may reduce AT stress, strain, and strain rate. Increases in step frequency of 5% above preferred frequency, regardless of foot strike pattern, may also lower peak AT stress and strain.

Force, reaction time, and precision of Kung Fu strikes.

Science.gov (United States)

Neto, Osmar Pinto; Bolander, Richard; Pacheco, Marcos Tadeu Tavares; Bir, Cynthia

2009-08-01

The goal was to compare values of force, precision, and reaction time of several martial arts punches and palm strikes performed by advanced and intermediate Kung Fu practitioners, both men and women. 13 Kung Fu practitioners, 10 men and three women, participated. Only the men, three advanced and seven intermediate, were considered for comparisons between levels. Reaction time values were obtained using two high speed cameras that recorded each strike at 2500 Hz. Force of impact was measured by a load cell. For comparisons of groups, force data were normalized by participant's body mass and height. Precision of the strikes was determined by a high speed pressure sensor. The results show that palm strikes were stronger than punches. Women in the study presented, on average, lower values of reaction time and force but higher values of precision than men. Advanced participants presented higher forces than intermediate participants. Significant negative correlations between the values of force and precision and the values of force and reaction time were also found.

Teaching Striking Skills in Elementary Physical Education Using Woodball

Science.gov (United States)

Chang, Seung Ho; Lee, Jihyun

2017-01-01

Object control (OC) skills are a part of fundamental motor skills and basic functional skills, which work as a prerequisite to becoming a skilled performer in many sports. Of various OC skills, striking is one of the most difficult to master due to a variety of interrelated movement components. A form of vertical or underarm striking is a more…

Fault slip and earthquake recurrence along strike-slip faults — Contributions of high-resolution geomorphic data

KAUST Repository

Zielke, Olaf

2015-01-01

the latter. While slip accumulation along a fault segment may be dominated by repetition of large, nearly constant offset increments, timing of surface-rupture is less regular. (C) 2014 Elsevier B.V. All rights reserved.

Feature Hepatitis: Hepatitis Can Strike Anyone

Science.gov (United States)

... Navigation Bar Home Current Issue Past Issues Feature Hepatitis Hepatitis Can Strike Anyone Past Issues / Spring 2009 Table ... from all walks of life are affected by hepatitis, especially hepatitis C, the most common form of ...

Physicians' strikes and the competing bases of physicians' moral obligations.

Science.gov (United States)

MacDougall, D Robert

2013-09-01

Many authors have addressed the morality of physicians' strikes on the assumption that medical practice is morally different from other kinds of occupations. This article analyzes three prominent theoretical accounts that attempt to ground such special moral obligations for physicians--practice-based accounts, utilitarian accounts, and social contract accounts--and assesses their applicability to the problem of the morality of strikes. After critiquing these views, it offers a fourth view grounding special moral obligations in voluntary commitments, and explains why this is a preferable basis for understanding physicians' moral obligations in general and especially as pertaining to strikes.

The Legislative Process as a Safeguard of the Public Servant´S Right to Go on Strike

Directory of Open Access Journals (Sweden)

Edilene Lôbo

2016-10-01

Full Text Available The right to go on strike can only be realized after a specific national bill – such law has been denied for decades. Acknowledged the omission it should be remedied. The Supreme Court, nonetheless, declared the legislative gap but created, by analogy, rules and procedural issues, bestowing upon the remaining courts discretion to establish a stricter regime and erga omnes effect replacing the legislator. This work criticizes the right´s regulation through judicial rulings removed from the legislative process. The methodology utilized, supported by Estate´s  functions  separation  and  democratic  process  theories,  consisted  in  exam  of legislation, court rulings AND specialized literature.

The Left Labourites and the General Strike of 1926 in the UK

Directory of Open Access Journals (Sweden)

Evgeniya G. Blosfeld

2017-12-01

Full Text Available The author analyses the left labourites’ attitude to the interaction of the Labour Party and trade unions and use of general strike as a means of the social struggle. Besides the article analyses the left labourites’ estimation of 1926 general strike and the causes of the defeat, and the strike of the miners who decided to continue it. The left labourites defended the branch principle of the trade unions’ organization based on the shopstewards’ model which was better adopted for the strike struggle. The left labourites took into account that the general structure of the labour movement would remain the same, but the Labour Party would take over the leadership from trade unions. The left labourites supported the peaceful way of transition to socialism and they considered the general strike to be analogy of social revolution or a means of pressure of the government for nationalization of the main economic branches and the improvement of the workers’ life conditions. Under extreme circumstances, the general strike was considered to be a means to prevent antidemocratic revolution. Evaluating the general strike of 1926, the author marks the absence of unity in the leadership, hesitations and inconsistency of the left labourites themselves. They didn’t give a single proposal about the improvement of the working-class movement organization except of state British Trade Unions Congress. As a result, the criticism of the General Council’s renegade position was bestowed upon the leadership of the Miners Federation who didn’t submit to the General Council order to stop the strike.

Factors affecting defensive strike behavior in Brown Treesnakes (Boiga irregularis) provoked by humans

Science.gov (United States)

Spencer, McKayka M.; Lardner, Bjorn; Mazurek, M.J.; Reed, Robert N.

2015-01-01

Striking is a typical antipredator defense exhibited by many species of snakes. While trapping Brown Treesnakes (Boiga irregularis) on Guam, we observed that snakes most frequently struck at an approaching person at a site where snakes had been trapped, marked, and handled in the past. Using a combination of between-sites and within-site comparisons, we assessed if the propensity to strike was correlated with capture histories (both recent and long-term), snake size, body condition (a proxy to nutritional stress), sex, or tail condition (broken or intact), while controlling for confounding variables. We confirmed that propensity to strike was higher at the site where we had been conducting capture-mark-recapture for several years. However, we were unable to demonstrate a correlation between striking tendencies and individual recent or long-term capture histories. The only morphological covariate that had an effect on strike propensity was sex, with females striking more often than males. After removing the site effect from our model, we found that snakes missing parts of their tails were more likely to strike than snakes with intact tails. We have yet to identify the factor(s) that cause the pronounced difference across sites in snake propensity to strike, and data from additional sites might help elucidate any geographical patterns.

Relationship between foot strike pattern, running speed, and footwear condition in recreational distance runners.

Science.gov (United States)

Cheung, Roy T H; Wong, Rodney Y L; Chung, Tim K W; Choi, R T; Leung, Wendy W Y; Shek, Diana H Y

2017-06-01

Compared to competitive runners, recreational runners appear to be more prone to injuries, which have been associated with foot strike patterns. Surprisingly, only few studies had examined the foot strike patterns outside laboratories. Therefore, this study compared the foot strike patterns in recreational runners at outdoor tracks with previously reported data. We also investigated the relationship between foot strike pattern, speed, and footwear in this cohort. Among 434 recreational runners analysed, 89.6% of them landed with rearfoot strike (RFS). Only 6.9 and 3.5% landed with midfoot and forefoot, respectively. A significant shift towards non-RFS was observed in our cohort, when compared with previously reported data. When speed increased by 1 m/s, the odds of having forefoot strike and midfoot strike relative to RFS increased by 2.3 times and 2.6 times, respectively. Runners were 9.2 times more likely to run with a forefoot strike in minimalists compared to regular running shoes, although 70% of runners in minimalists continued to use a RFS. These findings suggest that foot strike pattern may differ across running conditions and runners should consider these factors in order to mitigate potential injury.

Constraining slip rates and spacings for active normal faults

Science.gov (United States)

Cowie, Patience A.; Roberts, Gerald P.

2001-12-01

Numerous observations of extensional provinces indicate that neighbouring faults commonly slip at different rates and, moreover, may be active over different time intervals. These published observations include variations in slip rate measured along-strike of a fault array or fault zone, as well as significant across-strike differences in the timing and rates of movement on faults that have a similar orientation with respect to the regional stress field. Here we review published examples from the western USA, the North Sea, and central Greece, and present new data from the Italian Apennines that support the idea that such variations are systematic and thus to some extent predictable. The basis for the prediction is that: (1) the way in which a fault grows is fundamentally controlled by the ratio of maximum displacement to length, and (2) the regional strain rate must remain approximately constant through time. We show how data on fault lengths and displacements can be used to model the observed patterns of long-term slip rate where measured values are sparse. Specifically, we estimate the magnitude of spatial variation in slip rate along-strike and relate it to the across-strike spacing between active faults.

Implications of Incessant Strike Actions on the Implementation of Technical Education Programme in Nigeria

Science.gov (United States)

Adavbiele, J. A.

2015-01-01

This paper was designed to x-ray the implications of incessant strike actions on the implementation of Technical education programme in Nigeria. The paper took an exploratory view on the concept of strike actions in Nigeria with particular references on notable strike actions that have occurred in Nigeria. The types of strike were explained and…

Variation in Foot Strike Patterns among Habitually Barefoot and Shod Runners in Kenya.

Science.gov (United States)

Lieberman, Daniel E; Castillo, Eric R; Otarola-Castillo, Erik; Sang, Meshack K; Sigei, Timothy K; Ojiambo, Robert; Okutoyi, Paul; Pitsiladis, Yannis

2015-01-01

Runners are often categorized as forefoot, midfoot or rearfoot strikers, but how much and why do individuals vary in foot strike patterns when running on level terrain? This study used general linear mixed-effects models to explore both intra- and inter-individual variations in foot strike pattern among 48 Kalenjin-speaking participants from Kenya who varied in age, sex, body mass, height, running history, and habitual use of footwear. High speed video was used to measure lower extremity kinematics at ground contact in the sagittal plane while participants ran down 13 meter-long tracks with three variables independently controlled: speed, track stiffness, and step frequency. 72% of the habitually barefoot and 32% of the habitually shod participants used multiple strike types, with significantly higher levels of foot strike variation among individuals who ran less frequently and who used lower step frequencies. There was no effect of sex, age, height or weight on foot strike angle, but individuals were more likely to midfoot or forefoot strike when they ran on a stiff surface, had a high preferred stride frequency, were habitually barefoot, and had more experience running. It is hypothesized that strike type variation during running, including a more frequent use of forefoot and midfoot strikes, used to be greater before the introduction of cushioned shoes and paved surfaces.

Variation in Foot Strike Patterns among Habitually Barefoot and Shod Runners in Kenya.

Directory of Open Access Journals (Sweden)

Daniel E Lieberman

Full Text Available Runners are often categorized as forefoot, midfoot or rearfoot strikers, but how much and why do individuals vary in foot strike patterns when running on level terrain? This study used general linear mixed-effects models to explore both intra- and inter-individual variations in foot strike pattern among 48 Kalenjin-speaking participants from Kenya who varied in age, sex, body mass, height, running history, and habitual use of footwear. High speed video was used to measure lower extremity kinematics at ground contact in the sagittal plane while participants ran down 13 meter-long tracks with three variables independently controlled: speed, track stiffness, and step frequency. 72% of the habitually barefoot and 32% of the habitually shod participants used multiple strike types, with significantly higher levels of foot strike variation among individuals who ran less frequently and who used lower step frequencies. There was no effect of sex, age, height or weight on foot strike angle, but individuals were more likely to midfoot or forefoot strike when they ran on a stiff surface, had a high preferred stride frequency, were habitually barefoot, and had more experience running. It is hypothesized that strike type variation during running, including a more frequent use of forefoot and midfoot strikes, used to be greater before the introduction of cushioned shoes and paved surfaces.

Insights on the seismotectonics of the western part of northern Calabria (southern Italy) by integrated geological and geophysical data: Coexistence of shallow extensional and deep strike-slip kinematics

Science.gov (United States)

Ferranti, L.; Milano, G.; Pierro, M.

2017-11-01

We assess the seismotectonics of the western part of the border area between the Southern Apennines and Calabrian Arc, centered on the Mercure extensional basin, by integrating recent seismicity with a reconstruction of the structural frame from surface to deep crust. The analysis of low-magnitude (ML ≤ 3.5) events occurred in the area during 2013-2017, when evaluated in the context of the structural model, has revealed an unexpected complexity of seismotectonics processes. Hypocentral distribution and kinematics allow separating these events into three groups. Focal mechanisms of the shallower (kinematics. These results are consistent with the last kinematic event recorded on outcropping faults, and with the typical depth and kinematics of normal faulting earthquakes in the axial part of southern Italy. By contrast, intermediate ( 9-17 km) and deep ( 17-23 km) events have fault plane solutions characterized by strike- to reverse-oblique slip, but they differ from each other in the orientation of the principal axes. The intermediate events have P axes with a NE-SW trend, which is at odds with the NW-SE trend recorded by strike-slip earthquakes affecting the Apulia foreland plate in the eastern part of southern Italy. The intermediate events are interpreted to reflect reactivation of faults in the Apulia unit involved in thrust uplift, and appears aligned along an WNW-ESE trending deep crustal, possibly lithospheric boundary. Instead, deep events beneath the basin, which have P-axis with a NW-SE trend, hint to the activity of a deep overthrust of the Tyrrhenian back-arc basin crust over the continental crust of the Apulia margin, or alternatively, to a tear fault in the underthrust Apulia plate. Results of this work suggest that extensional faulting, as believed so far, does not solely characterizes the seismotectonics of the axial part of the Southern Apennines.

Expeditionary Strike Group: Command Structure Design Support

National Research Council Canada - National Science Library

Hutchins, Susan G; Kemple, William G; Kleinman, David L; Hocevar, Susan P

2005-01-01

An Expeditionary Strike Group (ESG) is a new capability mix that combines the combat power of three surface combatants and one submarine with an Amphibious Readiness Group/ Marine Expeditionary Unit...

[FORCE-FEEDING OR LIFE-SAVING? - DEALING WITH HUNGER STRIKES IN ISRAEL].

Science.gov (United States)

Siegal, Gil; Glick, Shimon; Offer-Stark, Irit; Steinberg, Avraham

2018-01-01

Force feeding of fasting hunger-striking prisoners is the subject of considerable controversy in Israel and elsewhere, posing a direct conflict between two basic ethical values: that of human life and respect for autonomy. The Israel Medical Association, as well as the World Medical Association, has taken the position that force feeding of such prisoners is an act of torture and is therefore unethical. However this paper presents an opposing view, which recently became the law in Israel, that, whereas the rights of prisoners to decree a hunger strike as a form of protest should be respected, if the prolongation of the strike reaches a stage of clear and present danger to the life and health of a prisoner, the saving of the prisoner's life must take precedence over considerations of autonomy. The paper present the steps that should be taken, including extensive and empathic efforts to persuade the prisoner to end his/her fast; gaining the approval of a hospital's ethics committee; and gaining the approval of a district court judge; the feeding is to be carried out in the most humane and sensitive manner as befitting a lifesaving procedure for any patient. This position is consistent with Israel's Basic Law: Human Dignity and Liberty, Israel's Patient Rights Law, Israel's "Do not stand idly by your fellow man's blood" Law, with several Israeli court decisions and in keeping with the dominant Israeli culture. Finally, instructions for physicians who object to such measures are discussed, ascertaining the freedom of conscience as well as preserving the life of the hunger-strikers.

Electric converters of electromagnetic strike machine with battery power

Science.gov (United States)

Usanov, K. M.; Volgin, A. V.; Kargin, V. A.; Moiseev, A. P.; Chetverikov, E. A.

2018-03-01

At present, the application of pulse linear electromagnetic engines to drive strike machines for immersion of rod elements into the soil, strike drilling of shallow wells, dynamic probing of soils is recognized as quite effective. The pulse linear electromagnetic engine performs discrete consumption and conversion of electrical energy into mechanical work. Pulse dosing of a stream transmitted by the battery source to the pulse linear electromagnetic engine of the energy is provided by the electrical converter. The electric converters with the control of an electromagnetic strike machine as functions of time and armature movement, which form the unipolar supply pulses of voltage and current necessary for the normal operation of a pulse linear electromagnetic engine, are proposed. Electric converters are stable in operation, implement the necessary range of output parameters control determined by the technological process conditions, have noise immunity and automatic disconnection of power supply in emergency modes.

Hematite (U-Th)/He thermochronometry constrains intraplate strike-slip faulting on the Kuh-e-Faghan Fault, central Iran

Science.gov (United States)

Calzolari, Gabriele; Rossetti, Federico; Ault, Alexis K.; Lucci, Federico; Olivetti, Valerio; Nozaem, Reza

2018-03-01

The Kuh-e-Faghan strike-slip fault system (KFF), located to the northern edge of the Lut Block in central Iran, developed through a Neogene-Quaternary pulsed history of eastward fault propagation and fault-related exhumation. This system is a consequence of the residual stresses transmitted from the Arabia-Eurasia convergent plate boundary. Here we integrate structural and textural analysis with new and previously published apatite fission-track (AFT) and apatite (U-Th)/He (apatite He) results, chlorite thermomentry, and hematite (U-Th)/He data from hematite-coated brittle fault surfaces to constrain the timing of tectonic activity and refine patterns of late Miocene-Pliocene burial and exhumation associated with the propagation of the KFF. Twenty-nine hematite (U-Th)/He (hematite He) dates from three striated hematite coated slip surfaces from the KFF fault core and damage zone yield individual dates from 12-2 Ma. Petrographic analysis and chlorite thermometry of a polyphase, fossil fluid system in the KFF fault core document that fluid circulation and mineralization transitioned from a closed system characterized by pressure solution and calcite growth to an open system characterized by hot hydrothermal (T = 239 ± 10 °C) fluids and hematite formation. Hematite microtextures and grain size analysis reveal primary and secondary syntectonic hematite fabrics, no evidence of hematite comminution and similar hematite He closure temperatures ( 60-85 °C) in each sample. Integration of these results with thermal history modeling of AFT and apatite He data shows that KFF activity in the late Miocene is characterized by an early stage of fault nucleation, fluid circulation, hematite mineralization, and eastward propagation not associated with vertical movement that lasted from 12 to 7 Ma. Hematite He, AFT, and apatite He data track a second phase of fault system activity involving fault-related exhumation initiating at 7 Ma and continuing until present time. Our new data

Lower extremity joint loads in habitual rearfoot and mid/forefoot strike runners with normal and shortened stride lengths.

Science.gov (United States)

Boyer, Elizabeth R; Derrick, Timothy R

2018-03-01

Our purpose was to compare joint loads between habitual rearfoot (hRF) and habitual mid/forefoot strikers (hFF), rearfoot (RFS) and mid/forefoot strike (FFS) patterns, and shorter stride lengths (SLs). Thirty-eight hRF and hFF ran at their normal SL, 5% and 10% shorter, as well as with the opposite foot strike. Three-dimensional ankle, knee, patellofemoral (PF) and hip contact forces were calculated. Nearly all contact forces decreased with a shorter SL (1.2-14.9% relative to preferred SL). In general, hRF had higher PF (hRF-RFS: 10.8 ± 1.4, hFF-FFS: 9.9 ± 2.0 BWs) and hip loads (axial hRF-RFS: -9.9 ± 0.9, hFF-FFS: -9.6 ± 1.0 BWs) than hFF. Many loads were similar between foot strike styles for the two groups, including axial and lateral hip, PF, posterior knee and shear ankle contact forces. Lateral knee and posterior hip contact forces were greater for RFS, and axial ankle and knee contact forces were greater for FFS. The tibia may be under greater loading with a FFS because of these greater axial forces. Summarising, a particular foot strike style does not universally decrease joint contact forces. However, shortening one's SL 10% decreased nearly all lower extremity contact forces, so it may hold potential to decrease overuse injuries associated with excessive joint loads.

BIRD/WILDLIFE STRIKE CONTROL FOR SAFER AIR ...

African Journals Online (AJOL)

Osondu

2012-06-05

Jun 5, 2012 ... Several factors including lack of adequate data, shortage of funds, inadequate training of staff and lack of ... Keywords: bird/wildlife, strike, aviation, hazard, control. Introduction ..... implications of some human activities within.

Body load in heel-strike running: the effect of a firm heel counter.

Science.gov (United States)

Jørgensen, U

1990-01-01

The effect of a firm heel counter in the shoe was studied in 11 athletes during submaximal heel-strike running on a treadmill under standardized conditions. The runners were tested in identical shoes with and without the distal 2 cm of the firm heel counter. Body load was expressed by absolute and relative VO2, surface EMG on the right leg, and g-force registration from an accelerometer below the right tibial tuberosity. The heel counter caused a 2.4% significant decrease in VO2, a reduction in musculoskeletal transients, and a decrease in the activity of the triceps surae and quadriceps muscles at heel strike. The changes found are expressions of kinematic adaptations in the body to increased or decreased load and provide functional evidence for the loading factor in the pathophysiology of overuse injuries.

Electrically conductive carbon fibre-reinforced composite for aircraft lightning strike protection

Science.gov (United States)

Katunin, Andrzej; Krukiewicz, Katarzyna; Turczyn, Roman; Sul, Przemysław; Bilewicz, Marcin

2017-05-01

Aircraft elements, especially elements of exterior fuselage, are subjected to damage caused by lightning strikes. Due to the fact that these elements are manufactured from polymeric composites in modern aircraft, and thus, they cannot conduct electrical charges, the lightning strikes cause burnouts in composite structures. Therefore, the effective lightning strike protection for such structures is highly desired. The solution presented in this paper is based on application of organic conductive fillers in the form of intrinsically conducting polymers and carbon fabric in order to ensure electrical conductivity of whole composite and simultaneously retain superior mechanical properties. The presented studies cover synthesis and manufacturing of the electrically conductive composite as well as its characterization with respect to mechanical and electrical properties. The performed studies indicate that the proposed material can be potentially considered as a constructional material for aircraft industry, which characterizes by good operational properties and low cost of manufacturing with respect to current lightning strike protection materials solutions.

2005 Significant U.S. Hurricane Strikes Poster

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The 2005 Significant U.S. Hurricane Strikes poster is one of two special edition posters for the Atlantic Hurricanes. This beautiful poster contains two sets of...

Are physicians strikes ever morally justifiable? A call for a return to tradition

Directory of Open Access Journals (Sweden)

Munyaradzi Mawere

2010-08-01

Full Text Available Though physicians strike provides an opportunity to generate more knowledge about the process in which legitimacy of an organization can be restored, it meets with a great deal of resistance not only by the public but from within the medical profession. This paper critically examines the legitimacy of strike by medical doctors heretofore referred to as physicians. Though critically reflecting on strikes of physicians in general, the paper makes more emphasis on Africa where physician strikes are rampant. More importantly, the paper argues that strike implies a failure for everyone in the organization (including the strikers themselves, not only the responsible government or authority. This is because when a strike occurs, an organization/fraternity is subjected to questions, scrutiny and slander. It becomes difficult to decouple what is said, decided and done. Traditionally, all medical fraternities the world-over are committed to acting comfortably to external demands- guaranteeing the patients lives and public health. By paying attention to external reactions, the medical fraternity adapts and learns what ought and should be done so that it is never again caught in the same messy. At the same time, the fraternity prepares itself for the future strikes. When the fraternity and those outside consider it is doing up to the external expectations, its lost legitimacy is restored. When legitimacy is restored, external pressure like once disturbed water returns to normal

Remarkable rates of lightning strike mortality in Malawi.

Science.gov (United States)

Mulder, Monique Borgerhoff; Msalu, Lameck; Caro, Tim; Salerno, Jonathan

2012-01-01

Livingstone's second mission site on the shore of Lake Malawi suffers very high rates of consequential lightning strikes. Comprehensive interviewing of victims and their relatives in seven Traditional Authorities in Nkhata Bay District, Malawi revealed that the annual rate of consequential strikes was 419/million, more than six times higher than that in other developing countries; the rate of deaths from lightning was 84/million/year, 5.4 times greater than the highest ever recorded. These remarkable figures reveal that lightning constitutes a significant stochastic source of mortality with potential life history consequences, but it should not deflect attention away from the more prominent causes of mortality in this rural area.

Continental United States Hurricane Strikes 1950-2012

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Continental U.S. Hurricane Strikes Poster is our most popular poster which is updated annually. The poster includes all hurricanes that affected the U.S. since...

Plantar loading changes with alterations in foot strike patterns during a single session in habitual rear foot strike female runners.

Science.gov (United States)

Kernozek, Thomas W; Vannatta, Charles N; Gheidi, Naghmeh; Kraus, Sydnie; Aminaka, Naoko

2016-03-01

Characterize plantar loading parameters when habitually rear foot strike (RFS) runners change their pattern to a non-rear foot strike (NRFS). Experimental. University biomechanics laboratory. Twenty three healthy female runners (Age: 22.17 ± 1.64 yrs; Height: 168.91 ± 5.46 cm; Mass: 64.29 ± 7.11 kg). Plantar loading was measured using an in-sole pressure sensor while running down a 20-m runway restricted to a range of 3.52-3.89 m/s under two conditions, using the runner's typical RFS, and an adapted NRFS pattern. Repeated measures multivariate analysis of variance was performed to detect differences in loading between these two conditions. Force and pressure variables were greater in the forefoot and phalanx in NRFS and greater in the heel and mid foot in RFS pattern, but the total force imposed upon the whole foot and contact time remained similar between conditions. Total peak pressure was higher and contact area was lower during NRFS running. The primary finding of this investigation is that there are distinctly different plantar loads when changing from a RFS to NRFS during running. So, during a transition from RFS to a NRFS pattern; a period of acclimation should be considered to allow for adaptations to these novel loads incurred on plantar regions of the foot. Copyright © 2015 Elsevier Ltd. All rights reserved.

Using regional moment tensors to constrain the kinematics and stress evolution of the 2010–2013 Canterbury earthquake sequence, South Island, New Zealand

Science.gov (United States)

Herman, Matthew W.; Herrmann, Robert B.; Benz, Harley M.; Furlong, Kevin P.

2014-01-01

On September 3, 2010, a MW 7.0 (U.S. Geological Survey moment magnitude) earthquake ruptured across the Canterbury Plains in South Island, New Zealand. Since then, New Zealand GNS Science has recorded over 10,000 aftershocks ML 2.0 and larger, including three destructive ~ MW 6.0 earthquakes near Christchurch. We treat the Canterbury earthquake sequence as an intraplate earthquake sequence, and compare its kinematics to an Andersonian model for fault slip in a uniform stress field. We determined moment magnitudes and double couple solutions for 150 earthquakes having MW 3.7 and larger through the use of a waveform inversion technique using data from broadband seismic stations on South Island, New Zealand. The majority (126) of these double couple solutions have strike-slip focal mechanisms, with right-lateral slip on ENE fault planes or equivalently left-lateral slip on SSE fault planes. The remaining focal mechanisms indicate reverse faulting, except for two normal faulting events. The strike-slip segments have compatible orientations for slip in a stress field with a horizontal σ1 oriented ~ N115°E, and horizontal σ3. The preference for right lateral strike-slip earthquakes suggests that these structures are inherited from previous stages of deformation. Reverse slip is interpreted to have occurred on previously existing structures in regions with an absence of existing structures optimally oriented for strike-slip deformation. Despite the variations in slip direction and faulting style, most aftershocks had nearly the same P-axis orientation, consistent with the regional σ1. There is no evidence for significant changes in these stress orientations throughout the Canterbury earthquake sequence.

Expert Anticipatory Skill in Striking Sports: A Review and a Model

Science.gov (United States)

Muller, Sean; Abernethy, Bruce

2012-01-01

Expert performers in striking sports can hit objects moving at high speed with incredible precision. Exceptionally well developed anticipation skills are necessary to cope with the severe constraints on interception. In this paper, we provide a review of the empirical evidence regarding expert interception in striking sports and propose a…

Properties of Lightning Strike Protection Coatings

Science.gov (United States)

Gagne, Martin

Composite materials are being increasingly used by many industries. In the case of aerospace companies, those materials are installed on their aircraft to save weight, and thus, fuel costs. These aircraft are lighter, but the loss of electrical conductivity makes aircraft vulnerable to lightning strikes, which hit commercial aircrafts on average once per year. This makes lightning strike protection very important, and while current metallic expanded copper foils offer good protection, they increase the weight of composites. Therefore, under the CRIAQ COMP-502 project, a team of industrial partners and academic researchers are investigating new conductive coatings with the following characteristics: High electromagnetic protection, high mechanical resistance, good environmental protection, manufacturability and moderate cost. The main objectives of this thesis, as part of this project, was to determine the main characteristics, such as electrical and tribomechanical properties, of conductive coatings on composite panels. Their properties were also to be tested after destructive tests such as current injection and environmental testing. Bombardier Aerospace provided the substrate, a composite of carbon fiber reinforced epoxy matrix, and the current commercial product, a surfacing film that includes an expanded copper foil used to compare with the other coatings. The conductive coatings fabricated by the students are: silver nanoparticles inside a binding matrix (PEDOT:PSS or a mix of Epoxy and PEDOT:PSS), silvered carbon nanofibers embedded in the surfacing film, cold sprayed tin, graphene oxide functionalized with silver nanowires, and electroless plated silver. Additionally as part of the project and thesis, magnetron sputtered aluminum coated samples were fabricated. There are three main types of tests to characterize the conductive coatings: electrical, mechanical and environmental. Electrical tests consist of finding the sheet resistance and specific resistivity

Law and ethics of strikes in the Nigerian health system | Mcfubara ...

African Journals Online (AJOL)

Despite that health services are essential, health sector strikes have continued. The purpose here was to examine the legal and ethical justification of strikes in the Nigerian health sector. Documentary analysis and literature reviews were carried out. It was found that the Trade Disputes Act and the National Health Act do not ...

Foot strike patterns and collision forces in habitually barefoot versus shod runners.

Science.gov (United States)

Lieberman, Daniel E; Venkadesan, Madhusudhan; Werbel, William A; Daoud, Adam I; D'Andrea, Susan; Davis, Irene S; Mang'eni, Robert Ojiambo; Pitsiladis, Yannis

2010-01-28

Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s. For most of human evolutionary history, runners were either barefoot or wore minimal footwear such as sandals or moccasins with smaller heels and little cushioning relative to modern running shoes. We wondered how runners coped with the impact caused by the foot colliding with the ground before the invention of the modern shoe. Here we show that habitually barefoot endurance runners often land on the fore-foot (fore-foot strike) before bringing down the heel, but they sometimes land with a flat foot (mid-foot strike) or, less often, on the heel (rear-foot strike). In contrast, habitually shod runners mostly rear-foot strike, facilitated by the elevated and cushioned heel of the modern running shoe. Kinematic and kinetic analyses show that even on hard surfaces, barefoot runners who fore-foot strike generate smaller collision forces than shod rear-foot strikers. This difference results primarily from a more plantarflexed foot at landing and more ankle compliance during impact, decreasing the effective mass of the body that collides with the ground. Fore-foot- and mid-foot-strike gaits were probably more common when humans ran barefoot or in minimal shoes, and may protect the feet and lower limbs from some of the impact-related injuries now experienced by a high percentage of runners.

The Poster Strikes Back

DEFF Research Database (Denmark)

Christensen, Line Hjorth

2005-01-01

The paper discusses fundamental issues in relation to placing graphic design in locations such as museums of decorative arts and living history museums. Based on my Ph.D. project on British commercial posters of the interwar years and approached from a combined perspective of museology, semiotics...... and design history, I argue that the poster during the interwar years inhabits a new active position. By exploiting and challenging the commercial and aesthetic paradox out of which it arose, the poster ‘strikes back' as a museologized, exhibited object. Rather than being absorbed into the city swirl...

COMPARISON OF COSEISMIC IONOSPHERIC DISTURBANCE WAVEFORMS REVISITED: STRIKE-SLIP, NORMAL, AND REVERSE FAULT EARTHQUAKE

Directory of Open Access Journals (Sweden)

Mokhamad Nur Cahyadi

2015-02-01

Full Text Available Using Total Electron Content (TEC measurements with Global Positioning System we studied ionospheric responses to three large earthquakes with difference focal mechanism that occurred in the Sumatra Andaman 26 December 2004, North off Sumatra 11 April 2012, and North Japan 7 December 2012. These earthquakes have different focal mechanisms, i.e. high-angle reverse, strike-slip, and normal faulting, respectively. TEC responses to the Sumatra Andaman 2004 and north Japan 2012 events initiated with positive changes. On the other hand, the initial TEC changes in the Sumatra 2012 earthquake showed both positive and negative polarities depending on the azimuth around the focal area. Such a variety may reflect differences in coseismic vertical crustal displacements, which are dominated by uplift and subsidence in the Sumatra 2012 event. This phenomena has same characteristic with 1994 Kuril Arch earthquake. There are three different propagation velocity in the Sumatra 2012 earthquake, within the first 300 km until 430 km, the CID propagation velocity was ~3 km/s, which is equal to the secod sound speed at the height of the ionospheric F-layer. Starting from 380 km until 750 km out from the epicenter, the disturbance seems to divide into two separate perturbations, with each propagating at a different velocity, about 1 km/s for the one and about 0.4 m/s for the other. The apparent velocity in the Sumatra Andaman 2004 and Japan 2012 propagated ~ 1 km/s and ~ 0.3 km/s, consistent with the sound speed at the ionospheric F layer height and internal gravity wave respectively. Resonant oscillation of TEC with a frequency of ~ 3.7 mHZ and ~4.4 mHz have been found in the Sumatra 2012 and Sumatra Andaman 2004 events. Those earthquakes, which occurred during a period of quiet geomagnetic activity, also showed clear preseismic TEC anomalies similar to those before the 2011 Tohoku-Oki and 2007 Bengkulu earthquake.   The positive anomalies started 30-60 minutes

Parkinsonian abnormality of foot strike: a phenomenon of ageing and/or one responsive to levodopa therapy?

Science.gov (United States)

Hughes, J R; Bowes, S G; Leeman, A L; O'Neill, C J; Deshmukh, A A; Nicholson, P W; Dobbs, S M; Dobbs, R J

1990-01-01

1. Normally during walking, the heel strikes the ground before the forefoot. Abnormalities of foot strike in idiopathic Parkinson's disease may be amenable to therapy: objective measurements may reveal response which is not clinically apparent. Occult changes in foot strike leading to instability may parallel the normal, age-related loss of striatal dopamine. 2. The nature of foot strike was studied using pedobarography in 160 healthy volunteers, aged 15 to 91 years. Although 16% of strikes were made simultaneously by heel and forefoot, there were no instances of the forefoot preceding the heel. No significant effect of age on an index of normality of foot strikes was detected (P greater than 0.3). 3. The effect on foot strike of substituting placebo for a morning dose of a levodopa/carbidopa combination was studied in a double-blind, cross-over trial in 14 patients, aged 64 to 88 years, with no overt fluctuations in control of their idiopathic Parkinson's disease in relation to dosing. On placebo treatment there was a highly significant (P = 0.004) reduction in the number of more normal strikes, i.e. heel strikes plus simultaneous heel and forefoot strikes. The effect appeared unrelated to the corresponding difference between active and placebo treatments in plasma concentration of levodopa or a metabolite of long half-time, 3-O-methyldopa (3OMD). However, it correlated negatively (P less than 0.05) with the mean of the 3OMD concentrations. 4. It appears that some abnormalities of foot strike due to Parkinson's disease are reversible. Employing test conditions, designed to provoke abnormalities of foot strike, might be useful in screening for pre-clinical Parkinson's disease. PMID:2306409

Physicians and strikes: can a walkout over the malpractice crisis be ethically justified?

Science.gov (United States)

Fiester, Autumn

2004-01-01

Malpractice insurance rates have created a crisis in American medicine. Rates are rising and reimbursements are not keeping pace. In response, physicians in the states hardest hit by this crisis are feeling compelled to take political action, and the current action of choice seems to be physician strikes. While the malpractice insurance crisis is acknowledged to be severe, does it justify the extreme action of a physician walkout? Should physicians engage in this type of collective action, and what are the costs to patients and the profession when such action is taken? I will offer three related arguments against physician strikes that constitute a prima facie prohibition against such action: first, strikes are intended to cause harm to patients; second, strikes are an affront to the physician-patient relationship; and, third, strikes risk decreasing the public's respect for the medical profession. As with any prima facie obligation, there are justifying conditions that may override the moral prohibition, but I will argue that the current malpractice crisis does not rise to the level of such a justifying condition. While the malpractice crisis demands and justifies a political response on the part of the nation's physicians, strikes and slow-downs are not an ethically justified means to the legitimate end of controlling insurance costs.

Parkinsonian abnormality of foot strike: a phenomenon of ageing and/or one responsive to levodopa therapy?

OpenAIRE

Hughes, J R; Bowes, S G; Leeman, A L; O'Neill, C J; Deshmukh, A A; Nicholson, P W; Dobbs, S M; Dobbs, R J

1990-01-01

1. Normally during walking, the heel strikes the ground before the forefoot. Abnormalities of foot strike in idiopathic Parkinson's disease may be amenable to therapy: objective measurements may reveal response which is not clinically apparent. Occult changes in foot strike leading to instability may parallel the normal, age-related loss of striatal dopamine. 2. The nature of foot strike was studied using pedobarography in 160 healthy volunteers, aged 15 to 91 years. Although 16% of strikes w...

Heel–toe running: A new look at the influence of foot strike pattern on impact force

OpenAIRE

John A. Mercer; Sarah Horsch

2015-01-01

Background/Objective: It is important to understand the factors that influence the impact force observed during running, since the impact force is likely to be related to overuse injuries. The purpose of this study was to compare the impact force during running when participants were instructed to use different foot strike patterns: obvious heel strike (Obvious-HS), subtle heel strike (Subtle-HS), midfoot strike (Mid-FS), and fore foot strike (Fore-FS) patterns. Methods: Participants (n = ...

NATURE AND DRIVING FORCES OF STRIKE MOVEMENT IN MOLDOVA IN LATE 1980S

Directory of Open Access Journals (Sweden)

Галина Евгеньевна Слободянюк

2016-12-01

Full Text Available The article discloses the nature and driving forces of the republican protest strike movement in Moldova in the period of perestroika reformsand its impact on the emergence and development of the civil conflict,which became the catalyst for the territorial division of the republic and the creation of the self-proclaimed Transnistrian statehood.In the article there is presented the analysis of the process of formationand activity of the strike movement. The author shows that the United Council of LabourUnionswas the initiator, organizer and the main acting force of the protest of the workers' movement, defending the civil and constitutional rights of the Russian-speaking population of the Transdnistrian region of the Moldavian SSR. The article allows getting an idea of the ways and methods of struggle of the working movement against the Soviet Moldavia nationalist representatives of the Popular front, which operated on the territory of the republic of Moldova. Particular attention is paid to the reasons of occurrence and major activities of the strike movement.Moreover, there are analyzed the consequences of these actions for the further political development of Moldova.

The large 1956 earthquake in the South Aegean: Macroseismic field configuration, faulting, and neotectonics of Amorgos Island

Science.gov (United States)

Papadopoulos, Gerassimos A.; Pavlides, Spyros B.

1992-10-01

New field observations of the seismic intensity distribution of the large (M s = 7.4) South Aegean (Amorgos) earthquake of 9 July 1956 are presented. Interpretations based on local ground conditions, structural properties of buildings and peculiarities of the rupture process lead to a re-evaluation of the macroseismic field configuration. This, together with the aftershock epicentral distribution, quite well defines the earthquake rupture zone, which trends NE-SW and coincides with the Amorgos Astypalea trough. The lateral extent of the rupture zone, however, is about 40% smaller than that predicted for Aegean earthquakes of M s = 7.4. This discrepancy could be attributed to sea-bottom topography changes, which seem to control the rupture terminations, and to relatively high stressdrop with respect to other Aegean earthquakes. Fault plane solutions obtained by several authors indicate either mainly normal faulting with a significant right-lateral strike-slip component or predominantly strike-slip motion. The neotectonism of Amorgos Island, based on new field observations, aerial photograph analysis and fault mechanisms, is consistent with the dip-slip interpretation. The neotectonic master fault of Amorgos and the 1956 seismic faulting appear to belong to the same tectonic phase (NE-SW strike and a southeasterly dip). However, the significant right-lateral strike-slip component supports the idea that the Amorgos region deviates from the simple description for pure extension in back-arc conditions.

Independent effects of step length and foot strike pattern on tibiofemoral joint forces during running.

Science.gov (United States)

Bowersock, Collin D; Willy, Richard W; DeVita, Paul; Willson, John D

2017-10-01

The purpose of this study was to examine the effects of step length and foot strike pattern along with their interaction on tibiofemoral joint (TFJ) and medial compartment TFJ kinetics during running. Nineteen participants ran with a rear foot strike pattern at their preferred speed using a short (-10%), preferred, and long (+10%) step length. These step length conditions were then repeated using a forefoot strike pattern. Regardless of foot strike pattern, a 10% shorter step length resulted in decreased peak contact force, force impulse per step, force impulse per kilometre, and average loading rate at the TFJ and medial compartment, while a 10% increased step length had the opposite effects (all P forefoot strike pattern significantly lowered TFJ and medial compartment TFJ average loading rates compared with a rear foot strike pattern (both forefoot strike pattern produced the greatest reduction in peak medial compartment contact force (P < 0.05). Knowledge of these running modification effects may be relevant to the management or prevention of TFJ injury or pathology among runners.

Heel-toe running: A new look at the influence of foot strike pattern on impact force.

Science.gov (United States)

Mercer, John A; Horsch, Sarah

2015-06-01

It is important to understand the factors that influence the impact force observed during running, since the impact force is likely to be related to overuse injuries. The purpose of this study was to compare the impact force during running when participants were instructed to use different foot strike patterns: obvious heel strike (Obvious-HS), subtle heel strike (Subtle-HS), midfoot strike (Mid-FS), and fore foot strike (Fore-FS) patterns. Participants ( n  = 10, 25 ± 5.7 years, 70.2 ± 12.1 kg, 174.6 ± 7.2 cm) completed four foot strike patterns while running over ground: Obvious-HS, Subtle-HS, Mid-FS, and Fore-FS. Speed was controlled between conditions (random order). Vertical ground reaction forces were recorded (1000 Hz) along with the impact force, peak force, and stance time for analysis. A repeated measures analysis of variance was used to compare each variable across foot strike instructions, with post hoc comparisons contrasting Obvious-HS to each of the other conditions. Impact force was influenced by foot strike instructions, with Obvious-HS being greater than Subtle-HS and Fore-FS ( p   0.05). The peak force was not influenced by foot strike instructions ( p  > 0.05); stance time was longer during Obvious-HS than during Mid-FS or Fore-FS ( p   0.05). The unique observation of this study was that impact force was different when participants were instructed to run with either an Obvious-HS or a Subtle-HS at contact. Both these foot strike patterns would have been considered rear foot strike patterns, suggesting that something other than which specific part of the foot strikes the ground initially influenced impact force.

Combining Earthquake Focal Mechanism Inversion and Coulomb Friction Law to Yield Tectonic Stress Magnitudes in Strike-slip Faulting Regime

Science.gov (United States)

Soh, I.; Chang, C.

2017-12-01

The techniques for estimating present-day stress states by inverting multiple earthquake focal mechanism solutions (FMS) provide orientations of the three principal stresses and their relative magnitudes. In order to estimate absolute magnitudes of the stresses that are generally required to analyze faulting mechanics, we combine the relative stress magnitude parameter (R-value) derived from the inversion process and the concept of frictional equilibrium of stress state defined by Coulomb friction law. The stress inversion in Korean Peninsula using 152 FMS data (magnitude≥2.5) conducted at regularly spaced grid points yields a consistent strike-slip faulting regime in which the maximum (S1) and the minimum (S3) principal stresses act in horizontal planes (with an S1 azimuth in ENE-WSW) and the intermediate principal stress (S2) close to vertical. However, R-value varies from 0.28 to 0.75 depending on locations, systematically increasing eastward. Based on the assumptions that the vertical stress is lithostatic, pore pressure is hydrostatic, and the maximum differential stress (S1-S3) is limited by Byerlee's friction of optimally oriented faults for slip, we estimate absolute magnitudes of the two horizontal principal stresses using R-value. As R-value increases, so do the magnitudes of the horizontal stresses. Our estimation of the stress magnitudes shows that the maximum horizontal principal stress (S1) normalized by vertical stress tends to increase from 1.3 in the west to 1.8 in the east. The estimated variation of stress magnitudes is compatible with distinct clustering of faulting types in different regions. Normal faulting events are densely populated in the west region where the horizontal stress is relatively low, whereas numerous reverse faulting events prevail in the east offshore where the horizontal stress is relatively high. Such a characteristic distribution of distinct faulting types in different regions can only be explained in terms of stress

Inefficient postural responses to unexpected slips during walking in older adults.

Science.gov (United States)

Tang, P F; Woollacott, M H

1998-11-01

Slips account for a high percentage of falls and subsequent injuries in community-dwelling older adults but not in young adults. This phenomenon suggests that although active and healthy older adults preserve a mobility level comparable to that of young adults, these older adults may have difficulty generating efficient reactive postural responses when they slip. This study tested the hypothesis that active and healthy older adults use a less effective reactive balance strategy than young adults when experiencing an unexpected forward slip occurring at heel strike during walking. This less effective balance strategy would be manifested by slower and smaller postural responses, altered temporal and spatial organization of the postural responses, and greater upper trunk instability after the slip. Thirty-three young adults (age range=19-34 yrs, mean=25+/-4 yrs) and 32 community-dwelling older adults (age range=70-87 yrs, mean=74+/-14 yrs) participated. Subjects walked across a movable forceplate which simulated a forward slip at heel strike. Surface electromyography was recorded from bilateral leg, thigh, hip, and trunk muscles. Kinematic data were collected from the right (perturbed) side of the body. Although the predominant postural muscles and the activation sequence of these muscles were similar between the two age groups, the postural responses of older adults were of longer onset latencies, smaller magnitudes, and longer burst durations compared to young adults. Older adults also showed a longer coactivation duration for the ankle, knee, and trunk agonist/antagonist pairs on the perturbed side and for the knee agonist/antagonist pair on the nonperturbed side. Behaviorally, older adults became less stable after the slips. This was manifested by a higher incidence of being tripped (21 trials in older vs 5 trials in young adults) and a greater trunk hyperextension with respect to young adults. Large arm elevation was frequently used by older adults to assist in

Global strike hypersonic weapons

Science.gov (United States)

Lewis, Mark J.

2017-11-01

Beginning in the 1940's, the United States has pursued the development of hypersonic technologies, enabling atmospheric flight in excess of five times the speed of sound. Hypersonic flight has application to a range of military and civilian applications, including commercial transport, space access, and various weapons and sensing platforms. A number of flight tests of hypersonic vehicles have been conducted by countries around the world, including the United States, Russia, and China, that could lead the way to future hypersonic global strike weapon systems. These weapons would be especially effective at penetrating conventional defenses, and could pose a significant risk to national security.

Recent state of stress change in the Walker Lane zone, western Basin and Range province, United States

Science.gov (United States)

Bellier, Olivier; Zoback, Mary Lou

1995-06-01

the youngest striae observed on faults in Plio-Quaternary deposits. Geologic control on the timing of the change is poor; it is impossible to determine if there has been a single recent absolute change or if there is, rather, an alternating or cyclical variation in stress magnitudes. Our slip data, in particular, the cross-cutting normal and strike-slip striae on the same fault plane, are inconsistent with postulated simple strain partitioning of deformation within a single regional stress field suggested for the WLZ by Wesnousky and Jones [1994]. The location of the WLZ between the deep-seated regional extension of the Basin and Range and the right-lateral strike-slip regional tectonics of the San Andreas fault zone is probably responsible for the complex interaction of tectonic regimes in this transition zone. In early to mid-Tertiary time the WLZ appears to have had a similarly complex deformational history, in this case as a back arc or intra-arc region, accommodating at least part of the right-lateral component of oblique convergence as well as a component of extension.

Electromiographic and kinematic characteristics of Kung Fu Yau-Man palm strike.

Science.gov (United States)

Neto, O P; Magini, Marcio

2008-12-01

A kinematic and electromyographic analysis of Kung Fu (KF) Yau-Man palm strikes without impact is presented. An empirical model applied to data obtained by a high-speed camera describes the kinematic characteristics of the movement. The electromyographic patterns of the biceps brachii, brachioradialis and triceps brachii muscles were studied during the strike in the time (root mean square) and frequency (wavelet transform) domains. Eight KF practitioners participated in the investigation. A wooden board was placed in front of the subjects, and they were asked to perform the strike imagining a target above the board. The results show that the Yau-Man KF palm strike has very similar kinematic characteristics to a simple moderate speed elbow extension movement. All practitioners positioned themselves in relation to the wooden board in a way to achieve their highest hand speeds in the instant their hands crossed the board. The analyses of the electromyography data shows a well developed muscle coordination of the practitioners in agreement with kinematic results. The results of this paper are important not only for improving the performance of practitioners but also to demonstrate the applicability of KF in the process of motor control development.

Why Teach a 100-Year-Old Strike?: The "Bread and Roses" Centenary

Science.gov (United States)

Diamond, Norm

2012-01-01

Today's movement in support of the 99 percent is a reminder that throughout U.S. history, a major engine of change has been grass-roots organizing and solidarity. Major history textbooks, however, downplay the role of ordinary people in shaping events--especially those who formed labor unions and used the strike to assert their rights. One of the…

Geochemistry of travertine deposits in the Eastern Anatolia District: an example of the Karakoçan-Yoğunağaç (Elazığ) and Mazgirt-Dedebağ (Tunceli) travertines, Turkey

OpenAIRE

KALENDER, LEYLA; OKAN, ÖZLEM ÖZTEKİN; İNCEÖZ, MURAT; ÇETİNDAĞ, BAHATTİN; YILDIRIM, VESİLE

2015-01-01

The Karakoçan-Yoğunağaç (Elazığ) and Mazgirt-Dedebağ (Tunceli) travertines, which are related to thermal springs, are situated on the right-lateral strike-slip Karakoçan Fault Zone (KFZ) and left-lateral strike-slip Pamuklu Fault Zone (PFZ) in eastern Anatolia. The surface area of the travertines varies from m2 to km2. Morphologically, the travertines are classified as ridge, banded, and terrace types due to deposition in different ways, in the releasing/restraining bends of the KFZ and PFZ a...

A Comparison of Geodetic and Geologic Rates Prior to Large Strike-Slip Earthquakes: A Diversity of Earthquake-Cycle Behaviors?

Science.gov (United States)

Dolan, James F.; Meade, Brendan J.

2017-12-01

Comparison of preevent geodetic and geologic rates in three large-magnitude (Mw = 7.6-7.9) strike-slip earthquakes reveals a wide range of behaviors. Specifically, geodetic rates of 26-28 mm/yr for the North Anatolian fault along the 1999 MW = 7.6 Izmit rupture are ˜40% faster than Holocene geologic rates. In contrast, geodetic rates of ˜6-8 mm/yr along the Denali fault prior to the 2002 MW = 7.9 Denali earthquake are only approximately half as fast as the latest Pleistocene-Holocene geologic rate of ˜12 mm/yr. In the third example where a sufficiently long pre-earthquake geodetic time series exists, the geodetic and geologic rates along the 2001 MW = 7.8 Kokoxili rupture on the Kunlun fault are approximately equal at ˜11 mm/yr. These results are not readily explicable with extant earthquake-cycle modeling, suggesting that they may instead be due to some combination of regional kinematic fault interactions, temporal variations in the strength of lithospheric-scale shear zones, and/or variations in local relative plate motion rate. Whatever the exact causes of these variable behaviors, these observations indicate that either the ratio of geodetic to geologic rates before an earthquake may not be diagnostic of the time to the next earthquake, as predicted by many rheologically based geodynamic models of earthquake-cycle behavior, or different behaviors characterize different fault systems in a manner that is not yet understood or predictable.

Earthquake scaling laws for rupture geometry and slip heterogeneity

Science.gov (United States)

Thingbaijam, Kiran K. S.; Mai, P. Martin; Goda, Katsuichiro

2016-04-01

We analyze an extensive compilation of finite-fault rupture models to investigate earthquake scaling of source geometry and slip heterogeneity to derive new relationships for seismic and tsunami hazard assessment. Our dataset comprises 158 earthquakes with a total of 316 rupture models selected from the SRCMOD database (http://equake-rc.info/srcmod). We find that fault-length does not saturate with earthquake magnitude, while fault-width reveals inhibited growth due to the finite seismogenic thickness. For strike-slip earthquakes, fault-length grows more rapidly with increasing magnitude compared to events of other faulting types. Interestingly, our derived relationship falls between the L-model and W-model end-members. In contrast, both reverse and normal dip-slip events are more consistent with self-similar scaling of fault-length. However, fault-width scaling relationships for large strike-slip and normal dip-slip events, occurring on steeply dipping faults (δ~90° for strike-slip faults, and δ~60° for normal faults), deviate from self-similarity. Although reverse dip-slip events in general show self-similar scaling, the restricted growth of down-dip fault extent (with upper limit of ~200 km) can be seen for mega-thrust subduction events (M~9.0). Despite this fact, for a given earthquake magnitude, subduction reverse dip-slip events occupy relatively larger rupture area, compared to shallow crustal events. In addition, we characterize slip heterogeneity in terms of its probability distribution and spatial correlation structure to develop a complete stochastic random-field characterization of earthquake slip. We find that truncated exponential law best describes the probability distribution of slip, with observable scale parameters determined by the average and maximum slip. Applying Box-Cox transformation to slip distributions (to create quasi-normal distributed data) supports cube-root transformation, which also implies distinctive non-Gaussian slip

THE EFFECTS OF HEIGHT AND DISTANCE ON THE FORCE PRODUCTION AND ACCELERATION IN MARTIAL ARTS STRIKES

Directory of Open Access Journals (Sweden)

Cynthia A. Bir

2009-11-01

Full Text Available Almost all cultures have roots in some sort of self defence system and yet there is relatively little research in this area, outside of a sports related environment. This project investigated different applications of strikes from Kung Fu practitioners that have not been addressed before in the literature. Punch and palm strikes were directly compared from different heights and distances, with the use of a load cell, accelerometers, and high speed video. The data indicated that the arm accelerations of both strikes were similar, although the force and resulting acceleration of the target were significantly greater for the palm strikes. Additionally, the relative height at which the strike was delivered was also investigated. The overall conclusion is that the palm strike is a more effective strike for transferring force to an object. It can also be concluded that an attack to the chest would be ideal for maximizing impact force and moving an opponent off balance

Using a Sound Field to Reduce the Risks of Bird-Strike: An Experimental Approach.

Science.gov (United States)

Swaddle, John P; Ingrassia, Nicole M

2017-07-01

Each year, billions of birds collide with large human-made structures, such as building, towers, and turbines, causing substantial mortality. Such bird-strike, which is projected to increase, poses risks to populations of birds and causes significant economic costs to many industries. Mitigation technologies have been deployed in an attempt to reduce bird-strike, but have been met with limited success. One reason for bird-strike may be that birds fail to pay adequate attention to the space directly in front of them when in level, cruising flight. A warning signal projected in front of a potential strike surface might attract visual attention and reduce the risks of collision. We tested this idea in captive zebra finches (Taeniopygia guttata) that were trained to fly down a long corridor and through an open wooden frame. Once birds were trained, they each experienced three treatments at unpredictable times and in a randomized order: a loud sound field projected immediately in front of the open wooden frame; a mist net (i.e., a benign strike surface) placed inside the wooden frame; and both the loud sound and the mist net. We found that birds slowed their flight approximately 20% more when the sound field was projected in front of the mist net compared with when the mist net was presented alone. This reduction in velocity would equate to a substantial reduction in the force of any collision. In addition to slowing down, birds increased the angle of attack of their body and tail, potentially allowing for more maneuverable flight. Concomitantly, the only cases where birds avoided the mist net occurred in the sound-augmented treatment. Interestingly, the sound field by itself did not demonstrably alter flight. Although our study was conducted in a limited setting, the alterations of flight associated with our sound field has implications for reducing bird-strike in nature and we encourage researchers to test our ideas in field trials. © The Author 2017. Published by

Rearfoot striking runners are more economical than midfoot strikers.

Science.gov (United States)

Ogueta-Alday, Ana; Rodríguez-Marroyo, José Antonio; García-López, Juan

2014-03-01

This study aimed to analyze the influence of foot strike pattern on running economy and biomechanical characteristics in subelite runners with a similar performance level. Twenty subelite long-distance runners participated and were divided into two groups according to their foot strike pattern: rearfoot (RF, n = 10) and midfoot (MF, n = 10) strikers. Anthropometric characteristics were measured (height, body mass, body mass index, skinfolds, circumferences, and lengths); physiological (VO2max, anaerobic threshold, and running economy) and biomechanical characteristics (contact and flight times, step rate, and step length) were registered during both incremental and submaximal tests on a treadmill. There were no significant intergroup differences in anthropometrics, VO2max, or anaerobic threshold measures. RF strikers were 5.4%, 9.3%, and 5.0% more economical than MF at submaximal speeds (11, 13, and 15 km·h respectively, although the difference was not significant at 15 km·h, P = 0.07). Step rate and step length were not different between groups, but RF showed longer contact time (P Foot strike pattern affected both contact and flight times, which may explain the differences in running economy.

A model of high-rate indentation of a cylindrical striking pin into a deformable body

Science.gov (United States)

Zalazinskaya, E. A.; Zalazinsky, A. G.

2017-12-01

Mathematical modeling of an impact and high-rate indentation to a significant depth of a flat-faced hard cylindrical striking pin into a massive deformable target body is carried out. With the application of the kinematic extreme theorem of the plasticity theory and the kinetic energy variation theorem, the phase trajectories of the striking pin are calculated, the initial velocity of the striking pin in the body, the limit values of the inlet duct length, and the depth of striking pin penetration into the target are determined.

SAR-revealed slip partitioning on a bending fault plane for the 2014 Northern Nagano earthquake at the northern Itoigawa-Shizuoka tectonic line

Science.gov (United States)

Kobayashi, Tomokazu; Morishita, Yu; Yarai, Hiroshi

2018-05-01

By applying conventional cross-track synthetic aperture radar interferometry (InSAR) and multiple aperture InSAR techniques to ALOS-2 data acquired before and after the 2014 Northern Nagano, central Japan, earthquake, a three-dimensional ground displacement field has been successfully mapped. Crustal deformation is concentrated in and around the northern part of the Kamishiro Fault, which is the northernmost section of the Itoigawa-Shizuoka tectonic line. The full picture of the displacement field shows contraction in the northwest-southeast direction, but northeastward movement along the fault strike direction is prevalent in the northeast portion of the fault, which suggests that a strike-slip component is a significant part of the activity of this fault, in addition to a reverse faulting. Clear displacement discontinuities are recognized in the southern part of the source region, which falls just on the previously known Kamishiro Fault trace. We inverted the SAR and GNSS data to construct a slip distribution model; the preferred model of distributed slip on a two-plane fault surface shows a combination of reverse and left-lateral fault motions on a bending east-dipping fault surface with a dip of 30° in the shallow part and 50° in the deeper part. The hypocenter falls just on the estimated deeper fault plane where a left-lateral slip is inferred, whereas in the shallow part, a reverse slip is predominant, which causes surface ruptures on the ground. The slip partitioning may be accounted for by shear stress resulting from a reverse fault slip with left-lateral component at depth, for which a left-lateral slip is suppressed in the shallow part where the reverse slip is inferred. The slip distribution model with a bending fault surface, instead of a single fault plane, produces moment tensor solution with a non-double couple component, which is consistent with the seismically estimated mechanism.

Fault zone architecture of a major oblique-slip fault in the Rawil depression, Western Helvetic nappes, Switzerland

Science.gov (United States)

Gasser, D.; Mancktelow, N. S.

2009-04-01

solution seams and veins and in the sandstones of coarse breccia and veins. Later, straight, sharp fault planes cross-cut all these features. In all lithologies, common veins and calcite-cemented fault rocks indicate the strong involvement of fluids during faulting. Today, the southern Rawil depression and the Rhone Valley belong to one of the seismically most active regions in Switzerland. Seismogenic faults interpreted from earthquake focal mechanisms strike ENE-WSW to WNW-ESE, with dominant dextral strike-slip and minor normal components and epicentres at depths of the current stress field inferred from the current seismicity. This implies that the same mechanisms that formed these fault zones in the past may still persist at depth. The Rezli fault zone allows the detailed study of a fossil fault zone that can act as a model for processes still occurring at deeper levels in this seismically active region.

The impact of public transportation strikes on use of a bicycle share program in London: interrupted time series design.

Science.gov (United States)

Fuller, Daniel; Sahlqvist, Shannon; Cummins, Steven; Ogilvie, David

2012-01-01

To investigate the immediate and sustained effects of two London Underground strikes on use of a public bicycle share program. An interrupted time series design was used to examine the impact of two 24 hour strikes on the total number of trips per day and mean trip duration per day on the London public bicycle share program. The strikes occurred on September 6th and October 4th 2010 and limited service on the London Underground. The mean total number of trips per day over the whole study period was 14,699 (SD=5390) while the mean trip duration was 18.5 minutes (SD=3.7). Significant increases in daily trip count were observed following strike 1 (3864: 95% CI 125 to 7604) and strike 2 (11,293: 95% CI 5169 to 17,416). Events that greatly constrain the primary motorised mode of transportation for a population may have unintended short-term effects on travel behaviour. These findings suggest that limiting transportation options may have the potential to increase population levels of physical activity by promoting the use of cycling. Copyright © 2011 Elsevier Inc. All rights reserved.

Geo-electrical and geological strikes of the Mount Lamongan geothermal area, East Java, Indonesia – preliminary results

Science.gov (United States)

Nugraheni, L. R.; Niasari, S. W.; Nukman, M.

2018-04-01

Geothermal manifestations located in the Tiris, Mount Lamongan, Probolinggo, consist of warm springs. These warm springs have temperature from 35° until 45°C. Tiris fault has NW-SE dominant orientation, similar to some lineaments of maars and cinder cones around Mount Lamongan. The Mount Lamongan geothermal area is situated between Bromo and Argapura volcanoes. This study aims to map the geo-electrical and geological strikes in the study area. Phase tensor analysis has been performed in this study to determine geo-electrical strike of study area. Geological field campaign has been conducted to measure geological strikes. Then, orientation of geo-electrical strike was compared to geological strike. The result presents that the regional geological strike of study area is NW-SE while the orientation of geo-electrical strike is N-S.

The Palos Verdes Fault offshore southern California: late Pleistocene to present tectonic geomorphology, seascape evolution and slip rate estimate based on AUV and ROV surveys

Science.gov (United States)

Brothers, Daniel S.; Conrad, James E.; Maier, Katherine L.; Paull, Charles K.; McGann, Mary L.; Caress, David W.

2015-01-01

The Palos Verdes Fault (PVF) is one of few active faults in Southern California that crosses the shoreline and can be studied using both terrestrial and subaqueous methodologies. To characterize the near-seafloor fault morphology, tectonic influences on continental slope sedimentary processes and late Pleistocene to present slip rate, a grid of high-resolution multibeam bathymetric data, and chirp subbottom profiles were acquired with an autonomous underwater vehicle (AUV) along the main trace of PVF in water depths between 250 and 600 m. Radiocarbon dates were obtained from vibracores collected using a remotely operated vehicle (ROV) and ship-based gravity cores. The PVF is expressed as a well-defined seafloor lineation marked by subtle along-strike bends. Right-stepping transtensional bends exert first-order control on sediment flow dynamics and the spatial distribution of Holocene depocenters; deformed strata within a small pull-apart basin record punctuated growth faulting associated with at least three Holocene surface ruptures. An upper (shallower) landslide scarp, a buried sedimentary mound, and a deeper scarp have been right-laterally offset across the PVF by 55 ± 5, 52 ± 4 , and 39 ± 8 m, respectively. The ages of the upper scarp and buried mound are approximately 31 ka; the age of the deeper scarp is bracketed to 17–24 ka. These three piercing points bracket the late Pleistocene to present slip rate to 1.3–2.8 mm/yr and provide a best estimate of 1.6–1.9 mm/yr. The deformation observed along the PVF is characteristic of strike-slip faulting and accounts for 20–30% of the total right-lateral slip budget accommodated offshore Southern California.

Are physicians' strikes ever morally justifiable? A call for a return to ...

African Journals Online (AJOL)

Though physicians strike provides an opportunity to generate more knowledge about the process in which legitimacy of an organization can be restored, it meets with a great deal of resistance not only by the public but from within the medical profession. This paper critically examines the legitimacy of strike by medical ...

Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics.

Science.gov (United States)

Valenzuela, Kevin A; Lynn, Scott K; Mikelson, Lisa R; Noffal, Guillermo J; Judelson, Daniel A

2015-03-01

The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern -forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group - PFFG, PRFG) mixed model ANOVAs (p strike patterns during shod running can create alterations in certain lower limb kinematic and kinetic measures that are not dependent on the preferred foot strike pattern of the individual. This research also challenges the contention that the impact transient spike in the vertical ground reaction force curve is only present during a rear foot strike type of running gait. Key pointsFootstrike pattern changes should be individually considered and implemented based on individual histories/abilitiesForefoot strike patterns increase external dorsiflexion momentsRearfoot strike patterns increase external knee flexion momentsRecreational shod runners are able to mimic habitual mechanics of different foot strike patterns.

Repeated Evolution of Power-Amplified Predatory Strikes in Trap-Jaw Spiders.

Science.gov (United States)

Wood, Hannah M; Parkinson, Dilworth Y; Griswold, Charles E; Gillespie, Rosemary G; Elias, Damian O

2016-04-25

Small animals possess intriguing morphological and behavioral traits that allow them to capture prey, including innovative structural mechanisms that produce ballistic movements by amplifying power [1-6]. Power amplification occurs when an organism produces a relatively high power output by releasing slowly stored energy almost instantaneously, resulting in movements that surpass the maximal power output of muscles [7]. For example, trap-jaw, power-amplified mechanisms have been described for several ant genera [5, 8], which have evolved some of the fastest known movements in the animal kingdom [6]. However, power-amplified predatory strikes were not previously known in one of the largest animal classes, the arachnids. Mecysmaucheniidae spiders, which occur only in New Zealand and southern South America, are tiny, cryptic, ground-dwelling spiders that rely on hunting rather than web-building to capture prey [9]. Analysis of high-speed video revealed that power-amplified mechanisms occur in some mecysmaucheniid species, with the fastest species being two orders of magnitude faster than the slowest species. Molecular phylogenetic analysis revealed that power-amplified cheliceral strikes have evolved four times independently within the family. Furthermore, we identified morphological innovations that directly relate to cheliceral function: a highly modified carapace in which the cheliceral muscles are oriented horizontally; modification of a cheliceral sclerite to have muscle attachments; and, in the power-amplified species, a thicker clypeus and clypeal apodemes. These structural innovations may have set the stage for the parallel evolution of ballistic predatory strikes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Middle Pleistocene infill of Hinkley Valley by Mojave River sediment and associated lake sediment: Depositional architecture and deformation by strike-slip faults

Science.gov (United States)

Miller, David; Haddon, Elizabeth; Langenheim, Victoria; Cyr, Andrew J.; Wan, Elmira; Walkup, Laura; Starratt, Scott W.

2018-01-01

avulsed through the valley, rather than continuing toward Lake Manix, during the late Pleistocene. Two dextral strike-slip fault zones, the Lockhart and the Mt. General, fold and displace the distinctive stratigraphic units, as well as surficial late Pleistocene and Holocene deposits. The sedimentary architecture and the two fault zones provide a framework for evaluating groundwater flow in Hinkley Valley.

Vådområder, flyvepladser og risiko for bird strikes

DEFF Research Database (Denmark)

Christensen, Thomas Kjær; Hounisen, Jens Peder

2015-01-01

Rapporten udgør en opdatering af Teknisk anvisning nr. 23 fra DMU (Christensen & Hounisen 2006), omhandlende risikovurdering for bird strikes (kollisioner mellem fugle og fly) i danske lufthavne ved etablering af vådområder nær disse. Rapporten analyserer relationen mellem ændrede forekomster af...... søer og enge/moser indenfor lufthavnenes sikkerhedszoner på 13 km og forekomsten af bird strikes i perioden 2006-2013. Anbefalinger til placering og størrelse af vådområder i lufthavnenes sikkerhedszoner er opdateret på baggrund af rapportens resultater....

Triggered lightning strikes to aircraft and natural intracloud discharges

Science.gov (United States)

Mazur, Vladislav

1989-01-01

The physical model of Mazur (1989) for triggering lightning strikes by aircraft was used to interpret the initiation of intracloud flashes observed by the French UHF-VHF interferometric system. It is shown that both the intracloud discharges and airplane-triggered lightning strikes were initiated by simultaneous bidirectional development of the negative stepped leader and the positive leader-continous current process. However, the negative stepped leader phase in triggered flashes is of shorter duration (tens of milliseconds), than that in intracloud flashes (usually hundreds of milliseconds). This is considered to be due to the fact that, on the aircraft there is a single initiation process, versus the numerous initiation processes that occur inside the cloud.

Escape tectonism in the Gulf of Thailand: Paleogene left-lateral pull-apart rifting in the Vietnamese part of the Malay Basin

DEFF Research Database (Denmark)

Fyhn, Michael B.W.; Boldreel, Lars Ole; Nielsen, Lars H

2010-01-01

The Malay Basin represents one of the largest rift basins of SE Asia. Based on a comprehensive 2-D seismic database tied to wells covering mainly Vietnamese acreage, the evolution of the Vietnamese part of the basin is outlined and a new tectonic model is proposed for the development of the basin....... The Vietnamese part of the Malay Basin comprises a large and deep Paleogene pull-apart basin formed through Middle or Late Eocene to Oligocene left-lateral strike-slip along NNW-trending fault zones. The Tho Chu Fault Zone constitutes a significant Paleogene left-lateral strike-slip zone most likely associated......–Strending faults in the central part of the basin. However, the lack of inversion in Vietnamese territory only seems to merit a few kilometers of dextral inversion....

High Frequency Near-Field Ground Motion Excited by Strike-Slip Step Overs

Science.gov (United States)

Hu, Feng; Wen, Jian; Chen, Xiaofei

2018-03-01

We performed dynamic rupture simulations on step overs with 1-2 km step widths and present their corresponding horizontal peak ground velocity distributions in the near field within different frequency ranges. The rupture speeds on fault segments are determinant in controlling the near-field ground motion. A Mach wave impact area at the free surface, which can be inferred from the distribution of the ratio of the maximum fault-strike particle velocity to the maximum fault-normal particle velocity, is generated in the near field with sustained supershear ruptures on fault segments, and the Mach wave impact area cannot be detected with unsustained supershear ruptures alone. Sub-Rayleigh ruptures produce stronger ground motions beyond the end of fault segments. The existence of a low-velocity layer close to the free surface generates large amounts of high-frequency seismic radiation at step over discontinuities. For near-vertical step overs, normal stress perturbations on the primary fault caused by dipping structures affect the rupture speed transition, which further determines the distribution of the near-field ground motion. The presence of an extensional linking fault enhances the near-field ground motion in the extensional regime. This work helps us understand the characteristics of high-frequency seismic radiation in the vicinities of step overs and provides useful insights for interpreting the rupture speed distributions derived from the characteristics of near-field ground motion.

Strike type variation among Tarahumara Indians in minimal sandals versus conventional running shoes

Directory of Open Access Journals (Sweden)

Daniel E. Lieberman

2014-06-01

Conclusion: These data reinforce earlier studies that there is variation among foot strike patterns among minimally shod runners, but also support the hypothesis that foot stiffness and important aspects of running form, including foot strike, differ between runners who grow up using minimal versus modern, conventional footwear.

Dynamic response to strike-slip tectonic control on the deposition and evolution of the Baranof Fan, Gulf of Alaska

Science.gov (United States)

Walton, Maureen A. L.; Gulick, Sean P. S.; Reece, Robert S.; Barth, Ginger A.; Christeson, Gail L.; VanAvendonk, Harm J.

2014-01-01

The Baranof Fan is one of three large deep-sea fans in the Gulf of Alaska, and is a key component in understanding large-scale erosion and sedimentation patterns for southeast Alaska and western Canada. We integrate new and existing seismic reflection profiles to provide new constraints on the Baranof Fan area, geometry, volume, and channel development. We estimate the fan’s area and total sediment volume to be ∼323,000 km2 and ∼301,000 km3, respectively, making it among the largest deep-sea fans in the world. We show that the Baranof Fan consists of channel-levee deposits from at least three distinct aggradational channel systems: the currently active Horizon and Mukluk channels, and the waning system we call the Baranof channel. The oldest sedimentary deposits are in the northern fan, and the youngest deposits at the fan’s southern extent; in addition, the channels seem to avulse southward consistently through time. We suggest that Baranof Fan sediment is sourced from the Coast Mountains in southeastern Alaska, transported offshore most recently via fjord to glacial sea valley conduits. Because of the translation of the Pacific plate northwest past sediment sources on the North American plate along the Queen Charlotte strike-slip fault, we suggest that new channel formation, channel beheadings, and southward-migrating channel avulsions have been influenced by regional tectonics. Using a simplified tectonic reconstruction assuming a constant Pacific plate motion of 4.4 cm/yr, we estimate that Baranof Fan deposition initiated ca. 7 Ma.

Seismotectonics and fault structure of the California Central Coast

Science.gov (United States)

Hardebeck, Jeanne L.

2010-01-01

I present and interpret new earthquake relocations and focal mechanisms for the California Central Coast. The relocations improve upon catalog locations by using 3D seismic velocity models to account for lateral variations in structure and by using relative arrival times from waveform cross-correlation and double-difference methods to image seismicity features more sharply. Focal mechanisms are computed using ray tracing in the 3D velocity models. Seismicity alignments on the Hosgri fault confirm that it is vertical down to at least 12 km depth, and the focal mechanisms are consistent with right-lateral strike-slip motion on a vertical fault. A prominent, newly observed feature is an ~25 km long linear trend of seismicity running just offshore and parallel to the coastline in the region of Point Buchon, informally named the Shoreline fault. This seismicity trend is accompanied by a linear magnetic anomaly, and both the seismicity and the magnetic anomaly end where they obliquely meet the Hosgri fault. Focal mechanisms indicate that the Shoreline fault is a vertical strike-slip fault. Several seismicity lineations with vertical strike-slip mechanisms are observed in Estero Bay. Events greater than about 10 km depth in Estero Bay, however, exhibit reverse-faulting mechanisms, perhaps reflecting slip at the top of the remnant subducted slab. Strike-slip mechanisms are observed offshore along the Hosgri–San Simeon fault system and onshore along the West Huasna and Rinconada faults, while reverse mechanisms are generally confined to the region between these two systems. This suggests a model in which the reverse faulting is primarily due to restraining left-transfer of right-lateral slip.

The General Strike - An Artist Talk on the Work of Santiago Sierra & Claire Fontaine

OpenAIRE

Mansoor, Jaleh

2012-01-01

The General Strike, the organized refusal to work among a critical mass of laborers, has been attendant upon and responsive to the capitalist form of accumulation since the latter’s inception. Having variously emerged and receded as a broadly recognized means of resistance since the mid 19th century, the potential of a general strike to precipitate capitalism's inherent tendency to crisis was forcefully expressed by the anti-austerity movement in Greece and in Spain in 2012. A general strike ...

Managing the risks: An analysis of bird strike reporting at Part 139 Airports in Indiana 2001-2014

Directory of Open Access Journals (Sweden)

Flavio Mendonca

2017-04-01

Full Text Available Purpose: The purpose of the current study was fourfold: to identify bird strike reporting trends at Part 139 airports in Indiana (2001-2014 for comparison to national data; to determine which quarter of the year yields the most bird strike data; to gain a clearer understanding of the relationship between altitude and bird strikes, and to develop information based upon the data analyzed that can be used for the safety management of birds including comparisons to national data.  Design/methodology: The researchers in this study answered the research questions by reviewing, sorting, and analyzing existing data.  The data collection took place from March 01 to May 02, 2016. Two data sets were utilized for data collection. The National Wildlife Strike Database (NWSD and the FAA Air Traffic Activity System (ATADS. Findings: When compared to national data, Indiana Part 139 airports have seen a faster increase in bird strike reporting during 2012 and 2014. Aggregate data indicated June through September (Quarter 3 had a significantly higher frequency of bird strikes reported.  When examining bird strikes and altitude of occurrences, the exponential equation explained 95 % of the variation in number of strikes by 1,000-foot intervals from 1000 to 10,000 feet. Not surprisingly, the risk of bird strikes appears to decrease as altitude increases. Originality/value: This study adds to the body of knowledge by addressing the lack of published bird strike report analyses at a regional level.  It also connects data analyses to safety management system (SMS concepts and Wildlife Hazards Management Programs (WHMP. The aviation community can use regional bird strike data and information to develop or enhance existing wildlife hazard management programs, increase pilot awareness, and offers airport managerial implications.

Fault-Slip Data Analysis and Cover Versus Basement Fracture Patterns - Implications for Subsurface Technical Processes in Thuringia, Germany

Science.gov (United States)

Kasch, N.; Kley, J.; Navabpour, P.; Siegburg, M.; Malz, A.

2014-12-01

Recent investigations in Thuringia, Central Germany, focus on the potential for carbon sequestration, groundwater supply and geothermal energy. We report on the results of an integrated fault-slip data analysis to characterize the geometries and kinematics of systematic fractures in contrasting basement and cover rock lithologies. The lithostratigraphy of the area comprises locally exposed crystalline rocks and intermittently overlying Permian volcanic and clastic sedimentary rocks, together referred to as basement. A Late Permian sequence of evaporites, carbonates and shale constitutes the transition to the continuous sedimentary cover of Triassic age. Major NW-SE-striking fault zones and minor NNE-SSW-striking faults affect this stratigraphic succession. These characteristic narrow deforming areas ( 15 km) non-deforming areas suggesting localized zones of mechanical weakness, which can be confirmed by the frequent reactivation of single fault strands. Along the major fault zones, the basement and cover contain dominant inclined to sub-vertical NW-SE-striking fractures. These fractures indicate successive normal, dextral strike-slip and reverse senses of slip, evidencing events of NNE-SSW extension and contraction. Another system of mostly sub-vertical NNW-SSE- and NE-SW-striking conjugate strike-slip faults mainly developed within the cover implies NNE-SSW contraction and WNW-ESE extension. Earthquake focal mechanisms and in-situ stress measurements reveal a NW-SE trend for the modern SHmax. Nevertheless, fractures and fault-slip indicators are rare in the non-deforming areas, which characterizes Thuringia as a dual domain of (1) large unfractured areas and (2) narrow zones of high potential for technical applications. Our data therefore provide a basis for estimation of slip and dilation tendency of the contrasting fractures in the basement and cover under the present-day stress field, which must be taken into account for different subsurface technical

Interaction effects of stride angle and strike pattern on running economy.

Science.gov (United States)

Santos-Concejero, J; Tam, N; Granados, C; Irazusta, J; Bidaurrazaga-Letona, I; Zabala-Lili, J; Gil, S M

2014-12-01

This study aimed to investigate the relationship between stride angle and running economy (RE) in athletes with different foot strike patterns. 30 male runners completed 4 min running stages on a treadmill at different velocities. During the test, biomechanical variables such as stride angle, swing time, contact time, stride length and frequency were recorded using an optical measurement system. Their foot strike pattern was determined, and VO2 at velocities below the lactate threshold were measured to calculate RE. Midfoot/forefoot strikers had better RE than rearfoot strikers (201.5±5.6 ml · kg(-1) · km(-1) vs. 213.5±4.2 ml · kg(-1) · km(-1)respectively; p=0.019). Additionally, midfoot/fore-foot strikers presented higher stride angles than rearfoot strikers (p=0.043). Linear modelling analysis showed that stride angle is closely related to RE (r=0.62, pstrike pattern is likely to be more economical, whereas at any lower degree, the midfoot/forefoot strike pattern appears to be more desirable. A biomechanical running technique characterised by high stride angles and a midfoot/forefoot strike pattern is advantageous for a better RE. Athletes may find stride angle useful for improving RE. © Georg Thieme Verlag KG Stuttgart · New York.

Electromyographic Study of a Sequence of Yau-Man Kung Fu Palm Strikes with and without Impact.

Science.gov (United States)

Neto, Osmar Pinto; Magini, Marcio; Pacheco, Marcos T T

2007-01-01

IN MARTIAL ARTS AND CONTACT SPORTS, STRIKES ARE OFTEN TRAINED IN TWO DIFFERENT WAYS: with and without impacts. This study aims to compare the electromyographical activity (EMG) of the triceps brachii (TB), biceps brachii (BB) and brachioradialis (BR) muscles during strikes with and without impacts. Eight Yau-Man Kung Fu practitioners participated in the experiment. Each participant performed 5 sequences of 5 consecutive KF Yau-Man palm strikes with no impact intercalated with 5 sequences of 5 repetitions targeting a KF training shield. Surface EMG signals were obtained from the TB, BB, and RB for 3.0 seconds using an eight-channel module with a total amplifier gain of 2000 and sampled at 3500 Hz. The EMG analyses were done in the time (rms) and frequency (wavelet) domains. For the frequency domain, Morlet wavelet power spectra were obtained and an original method was used to quantify statistically significant regions on the power spectra. The results both in the time and frequency domains indicate a higher TB and BR muscle activity for the strikes with impacts. No significant difference was found for the BB in the two different scenarios. In addition, the results show that the wavelet power spectra pattern for the three analysed muscles obtained from the strikes with and without impacts were similar. Key pointsEMG analysis of a sequence of Kung Fu strikes demonstrates higher Triceps Brachii and Brachioradialis muscle activity for strikes with impact than strikes without impact.An original reliable method for quantifying EMG wavelet transform results is presented.EMG wavelet power spectra describe muscle roles during a Kung Fu sequence of strikes.

Delayed Onset of Atrial Fibrillation and Ventricular Tachycardia after an Automobile Lightning Strike.

Science.gov (United States)

Drigalla, Dorian; Essler, Shannon E; Stone, C Keith

2017-11-01

Lightning strike is a rare medical emergency. The primary cause of death in lightning strike victims is immediate cardiac arrest. The mortality rate from lightning exposure can be as high as 30%, with up to 70% of patients left with significant morbidity. An 86-year-old male was struck by lightning while driving his vehicle and crashed. On initial emergency medical services evaluation, he was asymptomatic with normal vital signs. During his transport, he lost consciousness several times and was found to be in atrial fibrillation with intermittent runs of ventricular tachycardia during the unconscious periods. In the emergency department, atrial fibrillation persisted and he experienced additional episodes of ventricular tachycardia. He was treated with i.v. amiodarone and admitted to cardiovascular intensive care unit, where he converted to a normal sinus rhythm on the amiodarone drip. He was discharged home without rhythm-control medications and did not have further episodes of dysrhythmias on follow-up visits. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Lightning strikes are one of the most common injuries suffered from natural phenomenon, and short-term mortality ordinarily depends on the cardiac effects. This case demonstrates that the cardiac effects can be multiple, delayed, and recurrent, which compels the emergency physician to be vigilant in the initial evaluation and ongoing observation of patients with lightning injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

When the Ocean Strikes Back

DEFF Research Database (Denmark)

Gebauer, Mirjam

2013-01-01

The disaster scenario is one of the predominant settings we find unfold in the pop-cultural imagination, namely in films and novels. In recent years, as increased awareness of environmental issues affect the agendas of public debate, we also see local and increasingly global environmental disasters...... is evolving caused by an intelligent life form of the deep sea striking back at mankind. This article aims at discussing in what ways The Swarm uses elements and patterns of the pop-cultural disaster imagination, specifically the disaster and science fiction movie of the 1990s. Furthermore, it investigates...

The role of trade union organization in solving labor disputes and strikes in Vietnam

Directory of Open Access Journals (Sweden)

Nguen T.H.

2017-01-01

Full Text Available the article describes the role of the trade union organization in solving labor disputes and strikes and the legal basis of the role of trade union organization in solving labor disputes and strikes in Vietnam.

Strong paleoearthquakes along the Talas-Fergana Fault, Kyrgyzstan

Directory of Open Access Journals (Sweden)

A.M. Korzhenkov

2014-02-01

Full Text Available The Talas-Fergana Fault, the largest strike-slip structure in Centred. Asia, forms an obliquely oriented boundary between the northeastern and southwestern parts of the Tianshan mountain belt. The fault underwent active right-lateral strike-slip during the Paleozoic, with right-lateral movements being rejuvenated in the Late Cenozoic. Tectonic movements along the intracontinental strike-slip faults contribute to absorb part of the regional crustal shortening linked to the India-Eurasia collision; knowledge of strike-slip motions along the Talas-Fergana Fault are necessary for a complete assessment of the active deformation of the Tianshan orogen. To improve our understanding of the intracontinental deformation of the Tianshan mountain belt and the occurrence of strong earthquakes along the whole length of the Talas-Fergana Fault, we identify features of relief arising during strong paleoearthquakes along the Talas-Fergana Fault, fault segmentation, the length of seismogenic ruptures, and the energy and age of ancient catastrophes. We show that during neotectonic time the fault developed as a dextral strike-slip fault, with possible dextral displacements spreading to secondary fault planes north of the main fault trace. We determine rates of Holocene and Late Pleistocene dextral movements, and our radiocarbon dating indicates tens of strong earthquakes occurring along the fault zone during arid interval of 15800 years. The reoccurrence of strong earthquakes along the Talas-Fergana Fault zone during the second half of the Holocene is about 300 years. The next strong earthquake along the fault will most probably occur along its southeastern chain during the next several decades. Seismotectonic deformation parameters indicate that M > 7 earthquakes with oscillation intensity I > IX have occurred.

Documentation of programs that compute 1) static tilts for a spatially variable slip distribution, and 2) quasi-static tilts produced by an expanding dislocation loop with a spatially variable slip distribution

Science.gov (United States)

McHugh, Stuart

1976-01-01

The material in this report is concerned with the effects of a vertically oriented rectangular dislocation loop on the tilts observed at the free surface of an elastic half-space. Part I examines the effect of a spatially variable static strike-slip distribution across the slip surface. The tilt components as a function of distance parallel, or perpendicular, to the strike of the slip surface are displayed for different slip-versus-distance profiles. Part II examines the effect of spatially and temporally variable slip distributions across the dislocation loop on the quasi-static tilts at the free surface of an elastic half space. The model discussed in part II may be used to generate theoretical tilt versus time curves produced by creep events.

High-Precision Locations and the Stress Field from Instrumental Seismicity, Moment Tensors, and Short-Period Mechanisms through the Mina Deflection, Central Walker Lane

Science.gov (United States)

Ruhl, C. J.; Smith, K. D.

2012-12-01

The Mina Deflection (MD) region of the central Walker Lane of eastern California and western Nevada, is a complex zone of northeast-trending normal, and primarily left-lateral strike-slip to oblique-slip faulting that separates the Southern Walker Lane (SWL) from a series of east-tilted normal fault blocks in the Central Walker Lane (CWL) (Faulds and Henry, 2008; Surpless, 2008). The MD accommodates the transfer of right-lateral strike-slip motion from northwest-striking faults in the SWL to a series of left-stepping northwest-striking right-lateral strike-slip faults in the CWL, east of the Wassuk Range near Hawthorne, NV. The ~50 km wide ~80 km long right-step is a distinct transition in regional physiography that has been attributed to strain accommodation through pre-Cenozoic lithospheric structures. Several slip transfer mechanisms have been proposed within the MD, from clockwise rotation of high-angle fault blocks (Wesnousky, 2005), to low-angle displacement within the Silver Peak-Lone Mountain complex (Oldow et al., 2001), and curved fault arrays associated with localized basins and tectonic depressions (Ferranti et al., 2009). The region has been a regular source of M4+ events, the most recent being an extended sequence that included twenty-seven M 3.5+ earthquakes (largest event M 4.6) south of Hawthorne in 2011. These earthquakes (Mina, NV, and the 1932 M 7.1 Cedar Mountains earthquake east of the Pilot Mountains. Another persistent feature in the seismicity is an ~40 km long arcuate distribution of activity extending from approximately Queen Valley, north of the White Mountains, to Mono Lake that appears to reflect a southwestern boundary to northeast-striking structures in the MD. Here we develop high-precision relocations of instrumental seismicity in the MD from 1984 through 2012, including relocations of the 2004 sequence, and account for the historical seismic record. MT solutions from published reports and computed from recent M 3.5+ earthquakes as

Relationship between ionospheric plasma bubble occurrence and lightning strikes over the Amazon region

Directory of Open Access Journals (Sweden)

J. Sousasantos

2018-03-01

Full Text Available The vertical coupling between the troposphere and the ionosphere presents some remarkable features. Under intense tropospheric convection, gravity waves may be generated, and once they reach the ionosphere, these waves may seed instabilities and spread F and equatorial plasma bubble events may take place. Additionally, there is a close association between severe tropospheric convection and lightning strikes. In this work an investigation covering an equinox period (September–October during the deep solar minimum (2009 presents the relation between lightning strike activity and spread F (equatorial plasma bubble detected over a low-latitude Brazilian region. The results show a considerable correlation between these two phenomena. The common element in the center of this conformity seems to be the gravity waves. Once gravity waves and lightning strikes share the same source (intense tropospheric convection and the effects of such gravity waves in the ionosphere include the seeding of instabilities according to the gravity waves magnitude, the monitoring of the lightning strike activity seems to offer some information about the subsequent development of spread F over the equatorial region.

Relationship between ionospheric plasma bubble occurrence and lightning strikes over the Amazon region

Science.gov (United States)

Sousasantos, Jonas; Sobral, José Humberto Andrade; Alam Kherani, Esfhan; Magalhães Fares Saba, Marcelo; Rodolfo de Campos, Diovane

2018-03-01

The vertical coupling between the troposphere and the ionosphere presents some remarkable features. Under intense tropospheric convection, gravity waves may be generated, and once they reach the ionosphere, these waves may seed instabilities and spread F and equatorial plasma bubble events may take place. Additionally, there is a close association between severe tropospheric convection and lightning strikes. In this work an investigation covering an equinox period (September-October) during the deep solar minimum (2009) presents the relation between lightning strike activity and spread F (equatorial plasma bubble) detected over a low-latitude Brazilian region. The results show a considerable correlation between these two phenomena. The common element in the center of this conformity seems to be the gravity waves. Once gravity waves and lightning strikes share the same source (intense tropospheric convection) and the effects of such gravity waves in the ionosphere include the seeding of instabilities according to the gravity waves magnitude, the monitoring of the lightning strike activity seems to offer some information about the subsequent development of spread F over the equatorial region.

Select injury-related variables are affected by stride length and foot strike style during running.

Science.gov (United States)

Boyer, Elizabeth R; Derrick, Timothy R

2015-09-01

Some frontal plane and transverse plane variables have been associated with running injury, but it is not known if they differ with foot strike style or as stride length is shortened. To identify if step width, iliotibial band strain and strain rate, positive and negative free moment, pelvic drop, hip adduction, knee internal rotation, and rearfoot eversion differ between habitual rearfoot and habitual mid-/forefoot strikers when running with both a rearfoot strike (RFS) and a mid-/forefoot strike (FFS) at 3 stride lengths. Controlled laboratory study. A total of 42 healthy runners (21 habitual rearfoot, 21 habitual mid-/forefoot) ran overground at 3.35 m/s with both a RFS and a FFS at their preferred stride lengths and 5% and 10% shorter. Variables did not differ between habitual groups. Step width was 1.5 cm narrower for FFS, widening to 0.8 cm as stride length shortened. Iliotibial band strain and strain rate did not differ between foot strikes but decreased as stride length shortened (0.3% and 1.8%/s, respectively). Pelvic drop was reduced 0.7° for FFS compared with RFS, and both pelvic drop and hip adduction decreased as stride length shortened (0.8° and 1.5°, respectively). Peak knee internal rotation was not affected by foot strike or stride length. Peak rearfoot eversion was not different between foot strikes but decreased 0.6° as stride length shortened. Peak positive free moment (normalized to body weight [BW] and height [h]) was not affected by foot strike or stride length. Peak negative free moment was -0.0038 BW·m/h greater for FFS and decreased -0.0004 BW·m/h as stride length shortened. The small decreases in most variables as stride length shortened were likely associated with the concomitant wider step width. RFS had slightly greater pelvic drop, while FFS had slightly narrower step width and greater negative free moment. Shortening one's stride length may decrease or at least not increase propensity for running injuries based on the variables

Delayed Post Mortem Predation in Lightning Strike Carcasses ...

African Journals Online (AJOL)

Campbell Murn

An adult giraffe was struck dead by lightning on a game farm outside. Phalaborwa, South Africa in March 2014. Interestingly, delayed post-mortem predation occurred on the carcass, which according to the farm owners was an atypical phenomenon for the region. Delayed post-mortem scavenging on lightning strike ...

Influencia de un bloque rígido en un sistema de fallas de rumbo: modelamiento análogo Influence of a rigid block in a strike-slip fault system: analogue modelling

Directory of Open Access Journals (Sweden)

Thierry Nalpas

2011-01-01

Full Text Available En este trabajo se presenta un estudio de modelamiento análogo sobre la naturaleza, geometría y cinemática de la deformación a lo largo de fallas de rumbo dada la presencia de un bloque rígido en su trayectoria de deformación. Los modelos análogos están apropiadamente escalados considerando las características reológicas de los materiales que se desean contrastar en la deformación. Dos grandes parámetros fueron probados: la configuración del bloque rígido, variando su forma y tamaño, y el monto del desplazamiento. Los resultados experimentales muestran el desarrollo de rotaciones, fallas y pliegues como producto de la presencia de un bloque rígido en la trayectoria de falla. Los diversos casos geométricos probados pueden ser empleados para su comparación con sistemas de fallas de rumbo en los cuales existen diferencias litológicas de comportamiento reológico diferencial, como por ejemplo el caso del 'Núcleo rígido de Limón Verde' al sur de Chuquicamata, ubicado en la trayectoria del sistema de fallas de Domeyko.This work addresses the kinematic effects of a rigid block in strike-slip systems by using analogue models. The experiments (size, behaviour of materials were scaled down in order to represent deformation of the tested rheologic contrast conditions in deformation. Two main parameters were tested: the configuration of the rigid block, changing its form and size, and the amount of displacement. The experiments evidenced the development of rotations, faults and folds along the fault trajectory, as resulting from the presence of the rigid block during the deformation. Testing of diverse geometric situations may be used for comparison to strike-slip fault systems in which different lithologies and rheologic behaviour exist, for example, presence of the 'Limón Verde rigid core' along the Domeyko fault system, just south of Chuquicamata.

Heel–toe running: A new look at the influence of foot strike pattern on impact force

Directory of Open Access Journals (Sweden)

John A. Mercer

2015-06-01

Conclusion: The unique observation of this study was that impact force was different when participants were instructed to run with either an Obvious-HS or a Subtle-HS at contact. Both these foot strike patterns would have been considered rear foot strike patterns, suggesting that something other than which specific part of the foot strikes the ground initially influenced impact force.

Proliferation of Precision Strike: Issues for Congress

Science.gov (United States)

2012-05-14

industrial base. Finally, should Congress legislate requirements for DOD to develop precision strike countermeasures and then provide funding for that...Defense, Part 187 – Environmental Effects Abroad of Major Department of Defense Actions, Section 187.3: Definitions. 32 Bryan Clark and Dan Whiteneck...so many missiles ... referring to reports of Venezuelan arms flowing to Colombian guerrillas.... The Chavez regime also has close ties with

Foot-strike haemolysis in an ultramarathon runner.

Science.gov (United States)

Fazal, Abid A; Whittemore, Mary S; DeGeorge, Katharine C

2017-12-13

This case report describes mild anaemia and intravascular haemolysis in an otherwise healthy 41-year-old ultramarathon runner. In long-distance endurance athletes, trace gastrointestinal bleeding and plasma volume expansion are recognised sources of mild anaemia, often found incidentally. However, repetitive forceful foot striking can lead to blood cell lysis in the feet, resulting in a mild macrocytic anaemia and intravascular haemolysis, as was demonstrated in the patient described herein. Mild anaemia in runners, often called 'runner's pseudoanaemia', is typically clinically insignificant and does not require intervention. However, an unexplained anaemia can cause undue worry for otherwise healthy patients and lead to costly further testing, providing an argument against routine testing with complete blood counts in healthy, asymptomatic patients. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Micro-seismicity and seismotectonic study in Western Himalaya-Ladakh-Karakoram using local broadband seismic data

Science.gov (United States)

Kanna, Nagaraju; Gupta, Sandeep; Prakasam, K. S.

2018-02-01

We document the seismic activity and fault plane solutions (FPSs) in the Western Himalaya, Ladakh and Karakoram using data from 16 broadband seismographs operated during June 2002 to December 2003. We locate 206 earthquakes with a local magnitude in the range of 1.5 to 4.9 and calculate FPSs of 19 selected earthquakes based on moment tensor solutions. The earthquakes are distributed throughout the study region and indicate active tectonics in this region. The observed seismicity pattern is quite different than a well-defined pattern of seismicity, along the Main Central Thrust zone, in the eastern side of the study region (i.e., Kumaon-Garhwal Himalaya). In the Himalaya region, the earthquakes are distributed in the crust and upper mantle, whereas in the Ladakh-Karakoram area the earthquakes are mostly confined up to crustal depths. The fault plane solutions show a mixture of thrust, normal and strike-slip type mechanisms, which are well corroborated with the known faults/tectonics of the region. The normal fault earthquakes are observed along the Southern Tibet Detachment, Zanskar Shear Zone, Tso-Morari dome, and Kaurik-Chango fault; and suggest E-W extension tectonics in the Higher and Tethys Himalaya. The earthquakes of thrust mechanism with the left-lateral strike-slip component are seen along the Kistwar fault. The right-lateral strike-slip faulting with thrust component along the bending of the Main Boundary Thrust and Main Central Thrust shows the transpressional tectonics in this part of the Himalaya. The observed earthquakes with right-lateral strike-slip faulting indicate seismically active nature of the Karakoram fault.

Segmentation of Slow Slip Events in South Central Alaska Possibly Controlled by a Subducted Oceanic Plateau

Science.gov (United States)

Li, Haotian; Wei, Meng; Li, Duo; Liu, Yajing; Kim, YoungHee; Zhou, Shiyong

2018-01-01

Recent GPS observations show that slow slip events in south central Alaska are segmented along strike. Here we review several mechanisms that might contribute to this segmentation and focus on two: along-strike variation of slab geometry and effective normal stress. We then test them by running numerical simulations in the framework of rate-and-state friction with a nonplanar fault geometry. Results show that the segmentation is most likely related to the along-strike variation of the effective normal stress on the fault plane caused by the Yakutat Plateau. The Yakutat Plateau could affect the effective normal stress by either lowering the pore pressure in Upper Cook Inlet due to less fluids release or increasing the normal stress due to the extra buoyancy caused by the subducted Yakutat Plateau. We prefer the latter explanation because it is consistent with the relative amplitudes of the effective normal stress in Upper and Lower Cook Inlet and there is very little along-strike variation in Vp/Vs ratio in the fault zone from receiver function analysis. However, we cannot exclude the possibility that the difference in effective normal stress results from along-strike variation of pore pressure due to the uncertainties in the Vp/Vs estimates. Our work implies that a structural anomaly can have a long-lived effect on the subduction zone slip behavior and might be a driving factor on along-strike segmentation of slow slip events.

Spatial Comparisons of Tremor and Slow Slip as a Constraint on Fault Strength in the Northern Cascadia Subduction Zone

Science.gov (United States)

Hall, K.; Schmidt, D. A.; Houston, H.

2017-12-01

We measure displacement vectors from about 50 or more PANGA 3-component GPS stations to analyze six large ETS events from 2007 - 2016 in northern Cascadia, and invert for slip on a realistic plate interface. Our previous results indicated that significant slip of up to 2 cm occurs 10 to 15 km up-dip of the western edge of tremor beneath the Olympic Peninsula. This far up-dip aseismic slip persists in several of the ETS events. We also find that this offset appears to vary along-strike with a greater offset beneath the Olympic Peninsula and up into the Strait of Juan de Fuca in comparison to lower Puget Sound. To explain this, we explore how properties (temperature and permeability) of the overlying structure may influence fault strength. In our conceptual model, the observation that slip inferred from GPS can extend updip of tremor suggests that updip of the observed edge of tremor, seismogenic patches that could produce tremor and low frequency earthquakes (LFEs) are too strong to fail from the relatively minor amount of far up-dip slow slip. This is consistent with the observation that, within the ETS zone, down-dip LFEs occur frequently, whereas up-dip LFEs occur only during the largest ETS events and are unaffected by tidal stresses until the later stages of an ETS event. This suggests that the up-dip seismogenic patches have a larger discrepancy between their strength and stress states, and therefore require larger stress perturbations (such as those from a propagating ETS slip pulse) to trigger seismic failure. We consider whether lateral variations in overlying structure may explain the along-strike variations in far up-dip aseismic slip. There is an abrupt change in lithology from the meta-sediments of the Olympic accretionary complex to the mafic basalts of the Crescent terrane. The juxtaposition of these different lithologies could potentially explain the along-strike variations in far up-dip aseismic slip. We propose to explore whether relative changes

Light-induced bird strikes on vessels in Southwest Greenland

DEFF Research Database (Denmark)

Merkel, Flemming Ravn; Johansen, Kasper Lambert

2011-01-01

Light-induced bird strikes are known to occur when vessels navigate during darkness in icy waters using powerful searchlight. In Southwest Greenland, which is important internationally for wintering seabirds, we collected reports of incidents of bird strikes over 2–3 winters (2006–2009) from navy...... vessels, cargo vessels and trawlers (total n = 19). Forty-one incidents were reported: mainly close to land (birds were reported killed in a single incident. All occurred between 5 p.m. and 6 a.m. and significantly more birds were involved when...... visibility was poor (snow) rather than moderate or good. Among five seabird species reported, the common eider (Somateria mollissima) accounted for 95% of the bird casualties. Based on spatial analyses of data on vessel traffic intensity and common eider density we are able to predict areas with high risk...

Striking Inside Angola with 32 Battalion | Scheepers | Scientia ...

African Journals Online (AJOL)

Scientia Militaria: South African Journal of Military Studies. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 42, No 1 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Striking Inside Angola with 32 ...

Relationship between Achilles tendon properties and foot strike patterns in long-distance runners.

Science.gov (United States)

Kubo, Keitaro; Miyazaki, Daisuke; Tanaka, Shigeharu; Shimoju, Shozo; Tsunoda, Naoya

2015-01-01

The purpose of this study was to investigate the relationship between Achilles tendon properties and foot strike patterns in long-distance runners. Forty-one highly trained male long-distance runners participated in this study. Elongation of the Achilles tendon and aponeurosis of the medial gastrocnemius muscle were measured using ultrasonography, while the participants performed ramp isometric plantar flexion up to the voluntary maximum. The relationship between the estimated muscle force and tendon elongation during the ascending phase was fit to a linear regression, the slope of which was defined as stiffness. In addition, the cross-sectional area of the Achilles tendon was measured using ultrasonography. Foot strike patterns (forefoot, midfoot and rearfoot) during running were determined at submaximal velocity (18 km · h(-1)) on a treadmill. The number of each foot strike runner was 12 for the forefoot (29.3%), 12 for the midfoot (29.3%) and 17 for the rearfoot (41.5%). No significant differences were observed in the variables measured for the Achilles tendon among the three groups. These results suggested that the foot strike pattern during running did not affect the morphological or mechanical properties of the Achilles tendon in long-distance runners.

A numerical model for bird strike on sidewall structure of an aircraft nose

Directory of Open Access Journals (Sweden)

Liu Jun

2014-06-01

Full Text Available In order to examine the potential of using the coupled smooth particles hydrodynamic (SPH and finite element (FE method to predict the dynamic responses of aircraft structures in bird strike events, bird-strike tests on the sidewall structure of an aircraft nose are carried out and numerically simulated. The bird is modeled with SPH and described by the Murnaghan equation of state, while the structure is modeled with finite elements. A coupled SPH–FE method is developed to simulate the bird-strike tests and a numerical model is established using a commercial software PAM-CRASH. The bird model shows no signs of instability and correctly modeled the break-up of the bird into particles. Finally the dynamic response such as strains in the skin is simulated and compared with test results, and the simulated deformation and fracture process of the sidewall structure is compared with images recorded by a high speed camera. Good agreement between the simulation results and test data indicates that the coupled SPH–FE method can provide a very powerful tool in predicting the dynamic responses of aircraft structures in events of bird strike.

Making inference from wildlife collision data: inferring predator absence from prey strikes

Directory of Open Access Journals (Sweden)

Peter Caley

2017-02-01

Full Text Available Wildlife collision data are ubiquitous, though challenging for making ecological inference due to typically irreducible uncertainty relating to the sampling process. We illustrate a new approach that is useful for generating inference from predator data arising from wildlife collisions. By simply conditioning on a second prey species sampled via the same collision process, and by using a biologically realistic numerical response functions, we can produce a coherent numerical response relationship between predator and prey. This relationship can then be used to make inference on the population size of the predator species, including the probability of extinction. The statistical conditioning enables us to account for unmeasured variation in factors influencing the runway strike incidence for individual airports and to enable valid comparisons. A practical application of the approach for testing hypotheses about the distribution and abundance of a predator species is illustrated using the hypothesized red fox incursion into Tasmania, Australia. We estimate that conditional on the numerical response between fox and lagomorph runway strikes on mainland Australia, the predictive probability of observing no runway strikes of foxes in Tasmania after observing 15 lagomorph strikes is 0.001. We conclude there is enough evidence to safely reject the null hypothesis that there is a widespread red fox population in Tasmania at a population density consistent with prey availability. The method is novel and has potential wider application.

Identifying ideology: media representations of the Irving Oil Refinery strike, 1994-1996

Energy Technology Data Exchange (ETDEWEB)

Steuter, E.C.

1998-07-01

Media coverage of a strike at the Irving Oil Refinery in Saint John, New Brunswick which began in 1994 and lasted until 1996 is used as a background for the examination of ideology, used here in the more inclusive sense, one in which the term suggests a frame of mind without the coherence and easily recognized label usually associated with political ideology. Central issues such as monopoly ownership of the New Brunswick media by the Irving Group of Companies (also owners of the refinery) , the ideological presentation of strikes in general, and the representation of changing labour relations in a post-industrial, globally-oriented society are analyzed to show how these issues influenced media coverage. Four New Brunswick dailies as well as selected English-language dailies from other parts of Canada have been scrutinized in an effort to determine their ideological stand. It was found that restrictive ideologies such as liberalism or conservatism are on the decline; instead, more inclusive ideologies like defeatism and individualism were prominently featured especially by the St. John Telegraph-Journal in New Brunswick and other papers outside the province. The most striking finding was that if the media coverage of the Irving Refinery strike is representative of public opinion, the current organization of the provincial political economy is accepted as 'natural' by a majority of New Brunswickers.

Making inference from wildlife collision data: inferring predator absence from prey strikes.

Science.gov (United States)

Caley, Peter; Hosack, Geoffrey R; Barry, Simon C

2017-01-01

Wildlife collision data are ubiquitous, though challenging for making ecological inference due to typically irreducible uncertainty relating to the sampling process. We illustrate a new approach that is useful for generating inference from predator data arising from wildlife collisions. By simply conditioning on a second prey species sampled via the same collision process, and by using a biologically realistic numerical response functions, we can produce a coherent numerical response relationship between predator and prey. This relationship can then be used to make inference on the population size of the predator species, including the probability of extinction. The statistical conditioning enables us to account for unmeasured variation in factors influencing the runway strike incidence for individual airports and to enable valid comparisons. A practical application of the approach for testing hypotheses about the distribution and abundance of a predator species is illustrated using the hypothesized red fox incursion into Tasmania, Australia. We estimate that conditional on the numerical response between fox and lagomorph runway strikes on mainland Australia, the predictive probability of observing no runway strikes of foxes in Tasmania after observing 15 lagomorph strikes is 0.001. We conclude there is enough evidence to safely reject the null hypothesis that there is a widespread red fox population in Tasmania at a population density consistent with prey availability. The method is novel and has potential wider application.

Analogue modelling of strike-slip fault propagation across a rheological/morphological crustal anisotropy: implications for the morphotectonic evolution of the Gloria Fault - Tore Madeira Rise area in NE Atlantic.

Science.gov (United States)

Tomás, Ricardo; Rosas, Filipe M.; Duarte, João C.; Terrinha, Pedro; Kullberg, Maria C.; Almeida, Jaime; Barata, Frederico; Carvalho, Bruno; Almeida, Pedro

2015-04-01

The Gloria Fault (GF) marks the E-W dextral transcurrent plate boundary between Eurasia and Africa in NE Atlantic, displaying complying high magnitude (historical and instrumental) seismic activity (e.g. M=7.1 in 1939 and M=8.4 in 1941, Bufforn et al., 1988), and cutting across a NNE-SSW 1000 km long bathymetric ridge: the so called Tore-Madeira Rise - TMR (rising in average 3km above the abyssal plain). The precise origin and tectono-magmatic evolution of the TMR is still not fully understood, although reported wide-angle refraction data points to a rheological configuration comprising an isostatically compensated thickened oceanic crust, possibly formed during a period of high accretion in the Mid-Atlantic Ridge (Pierce and Barton, 1991). Widespread evidence for volcanic activity has also been recognized, spanning from late Cretaceous to Present (Geldmacher et al. 2006, Merle et al. 2009), noticeably with the most recent volcanism (~500 Ky) occurring as tectonically aligned volcanic plugs, distributed along the E-W tectonic trend of the GF-related structures. To better understand the complex interference at play in this key area between the tectonic structures (essentially determined by the Gloria Fault system), the present and past magmatic activity and the resulting seafloor morphology, a series of dynamically scaled analogue modelling experiments have been conceived and carried out. The main focus of this experimental work was to decipher the potential influence of a rheological vs. morphological anisotropy (accounting for the TMR) on the lateral propagation of a major right-lateral strike-slip fault (representing the GF). The preliminary comparison of the obtained experimental results with the natural morphotectonic pattern in the study area reveals, not only a strong tectonic control of the ongoing volcanism, manifested by the observed preferred directions of aligned volcanic plugs, but also a so far unsuspected deflection/distributed pattern of several

Changes in foot and shank coupling due to alterations in foot strike pattern during running.

Science.gov (United States)

Pohl, Michael B; Buckley, John G

2008-03-01

Determining if and how the kinematic relationship between adjacent body segments changes when an individual's gait pattern is experimentally manipulated can yield insight into the robustness of the kinematic coupling across the associated joint(s). The aim of this study was to assess the effects on the kinematic coupling between the forefoot, rearfoot and shank during ground contact of running with alteration in foot strike pattern. Twelve subjects ran over-ground using three different foot strike patterns (heel strike, forefoot strike, toe running). Kinematic data were collected of the forefoot, rearfoot and shank, which were modelled as rigid segments. Coupling at the ankle-complex and midfoot joints was assessed using cross-correlation and vector coding techniques. In general good coupling was found between rearfoot frontal plane motion and transverse plane shank rotation regardless of foot strike pattern. Forefoot motion was also strongly coupled with rearfoot frontal plane motion. Subtle differences were noted in the amount of rearfoot eversion transferred into shank internal rotation in the first 10-15% of stance during heel strike running compared to forefoot and toe running, and this was accompanied by small alterations in forefoot kinematics. These findings indicate that during ground contact in running there is strong coupling between the rearfoot and shank via the action of the joints in the ankle-complex. In addition, there was good coupling of both sagittal and transverse plane forefoot with rearfoot frontal plane motion via the action of the midfoot joints.

EDITORIAL Plagiarism - time to strike at the epidemic

African Journals Online (AJOL)

admin

Plagiarism - time to strike at the epidemic. Lukman Yusuf1, Abraham Aseffa2. We live in a globalized world where information is instantly shared across continents. The number of biomedical journals available for reference is quite enormous and there is a sudden huge surge of free open access journals in the last few years ...

Seismic and geodetic signatures of fault slip at the Slumgullion Landslide Natural Laboratory

Science.gov (United States)

Gomberg, J.; Schulz, W.; Bodin, P.; Kean, J.

2011-01-01

We tested the hypothesis that the Slumgullion landslide is a useful natural laboratory for observing fault slip, specifically that slip along its basal surface and side-bounding strike-slip faults occurs with comparable richness of aseismic and seismic modes as along crustal- and plate-scale boundaries. Our study provides new constraints on models governing landslide motion. We monitored landslide deformation with temporary deployments of a 29-element prism array surveyed by a robotic theodolite and an 88-station seismic network that complemented permanent extensometers and environmental instrumentation. Aseismic deformation observations show that large blocks of the landslide move steadily at approximately centimeters per day, possibly punctuated by variations of a few millimeters, while localized transient slip episodes of blocks less than a few tens of meters across occur frequently. We recorded a rich variety of seismic signals, nearly all of which originated outside the monitoring network boundaries or from the side-bounding strike-slip faults. The landslide basal surface beneath our seismic network likely slipped almost completely aseismically. Our results provide independent corroboration of previous inferences that dilatant strengthening along sections of the side-bounding strike-slip faults controls the overall landslide motion, acting as seismically radiating brakes that limit acceleration of the aseismically slipping basal surface. Dilatant strengthening has also been invoked in recent models of transient slip and tremor sources along crustal- and plate-scale faults suggesting that the landslide may indeed be a useful natural laboratory for testing predictions of specific mechanisms that control fault slip at all scales.

Refining fault slip rates using multiple displaced terrace risers-An example from the Honey Lake fault, NE California, USA

Science.gov (United States)

Gold, Ryan D.; Briggs, Richard W.; Crone, Anthony J.; DuRoss, Christopher B.

2017-11-01

Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4 difference observed globally) produce large uncertainties in the slip-rate estimate. In this investigation, we explore how the full range of displacements and bounding ages from multiple faulted terrace risers can be combined to yield a more accurate fault slip rate. We use 0.25-m cell size digital terrain models derived from airborne lidar data to analyze three sites where terrace risers are offset right-laterally by the Honey Lake fault in NE California, USA. We use ages for locally extensive subhorizontal surfaces to bracket the time of riser formation: an upper surface is the bed of abandoned Lake Lahontan having an age of 15.8 ± 0.6 ka and a lower surface is a fluvial terrace abandoned at 4.7 ± 0.1 ka. We estimate lateral offsets of the risers ranging between 6.6 and 28.3 m (median values), a greater than fourfold difference in values. The amount of offset corresponds to the riser's position relative to modern stream meanders: the smallest offset is in a meander cutbank position, whereas the larger offsets are in straight channel or meander point-bar positions. Taken in isolation, the individual terrace-riser offsets yield slip rates ranging from 0.3 to 7.1 mm/a. However, when the offset values are collectively assessed in a probabilistic framework, we find that a uniform (linear) slip rate of 1.6 mm/a (1.4-1.9 mm/a at 95% confidence) can satisfy the data, within their respective uncertainties. This investigation demonstrates that integrating observations of multiple offset elements (crest, midpoint, and base) from numerous faulted and dated terrace risers at closely spaced

Refining fault slip rates using multiple displaced terrace risers—An example from the Honey Lake fault, NE California, USA

Science.gov (United States)

Gold, Ryan D.; Briggs, Richard; Crone, Anthony J.; Duross, Christopher

2017-01-01

Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4 difference observed globally) produce large uncertainties in the slip-rate estimate. In this investigation, we explore how the full range of displacements and bounding ages from multiple faulted terrace risers can be combined to yield a more accurate fault slip rate. We use 0.25-m cell size digital terrain models derived from airborne lidar data to analyze three sites where terrace risers are offset right-laterally by the Honey Lake fault in NE California, USA. We use ages for locally extensive subhorizontal surfaces to bracket the time of riser formation: an upper surface is the bed of abandoned Lake Lahontan having an age of 15.8 ± 0.6 ka and a lower surface is a fluvial terrace abandoned at 4.7 ± 0.1 ka. We estimate lateral offsets of the risers ranging between 6.6 and 28.3 m (median values), a greater than fourfold difference in values. The amount of offset corresponds to the riser's position relative to modern stream meanders: the smallest offset is in a meander cutbank position, whereas the larger offsets are in straight channel or meander point-bar positions. Taken in isolation, the individual terrace-riser offsets yield slip rates ranging from 0.3 to 7.1 mm/a. However, when the offset values are collectively assessed in a probabilistic framework, we find that a uniform (linear) slip rate of 1.6 mm/a (1.4–1.9 mm/a at 95% confidence) can satisfy the data, within their respective uncertainties. This investigation demonstrates that integrating observations of multiple offset elements (crest, midpoint, and base) from numerous faulted and dated terrace risers at closely spaced

EU Water Governance: Striking the Right Balance between Regulatory Flexibility and Enforcement?

Directory of Open Access Journals (Sweden)

Olivia O. Green

2013-06-01

Full Text Available Considering the challenges and threats currently facing water management and the exacerbation of uncertainty by climate change, the need for flexible yet robust and legitimate environmental regulation is evident. The European Union took a novel approach toward sustainable water resource management with the passage of the EU Water Framework Directive in 2000. The Directive promotes sustainable water use through long-term protection of available water resources, progressively reduces discharges of hazardous substances in ground and surface waters, and mitigates the effects of floods and droughts. The lofty goal of achieving good status of all waters requires strong adaptive capacity, given the large amounts of uncertainty in water management. Striking the right balance between flexibility in local implementation and robust and enforceable standards is essential to promoting adaptive capacity in water governance, yet achieving these goals simultaneously poses unique difficulty. Applied resilience science reveals a conceptual framework for analyzing the adaptive capacity of governance structures that includes multiple overlapping levels of control or coordination, information flow horizontally and vertically, meaningful public participation, local capacity building, authority to respond to changed circumstances, and robust monitoring, system feedback, and enforcement. Analyzing the Directive through the lens of resilience science, we highlight key elements of modern European water management and their contribution to the resilience of the system and conclude that the potential lack of enforcement and adequate feedback of monitoring results does not promote managing for resilience. However, the scale-appropriate governance aspects of the EU approach promotes adaptive capacity by enabling vertical and horizontal information flow, building local capacity, and delegating control at multiple relevant scales.

12 weeks of simulated barefoot running changes foot-strike patterns in female runners.

Science.gov (United States)

McCarthy, C; Fleming, N; Donne, B; Blanksby, B

2014-05-01

To investigate the effect of a transition program of simulated barefoot running (SBR) on running kinematics and foot-strike patterns, female recreational athletes (n=9, age 29 ± 3 yrs) without SBR experience gradually increased running distance in Vibram FiveFingers SBR footwear over 12 weeks. Matched controls (n=10, age 30 ± 4 yrs) continued running in standard footwear. A 3-D motion analysis of treadmill running at 12 km/h(-1) was performed by both groups, barefoot and shod, pre- and post-intervention. Post-intervention data indicated a more-forefoot strike pattern in the SBR group compared to controls; both running barefoot (P>0.05), and shod (Pstrike (Pforefoot strike pattern and "barefoot" kinematics, regardless of preferred footwear. © Georg Thieme Verlag KG Stuttgart · New York.

Three-dimensional impact kinetics with foot-strike manipulations during running

Directory of Open Access Journals (Sweden)

Andrew D. Nordin

2017-12-01

Conclusion: Loading rate–time assessment identified contrasting impact characteristics in each direction and the 3D resultant following foot-strike manipulations, with potential implications for lower extremity structures in running.

Geologic map of the Bodie Hills, California and Nevada

Science.gov (United States)

John, David A.; du Bray, Edward A.; Box, Stephen E.; Vikre, Peter G.; Rytuba, James J.; Fleck, Robert J.; Moring, Barry C.

2015-01-01

The Bodie Hills covers about 1,200 km2 straddling the California-Nevada state boundary just north of Mono Lake in the western part of the Basin and Range Province, about 20 km east of the central Sierra Nevada. The area is mostly underlain by the partly overlapping, middle to late Miocene Bodie Hills volcanic field and Pliocene to late Pleistocene Aurora volcanic field (John and others, 2012). Upper Miocene to Pliocene sedimentary deposits, mostly basin-filling sediments, gravel deposits, and fanglomerates, lap onto the west, north, and east sides of the Bodie Hills, where they cover older Miocene volcanic rocks. Quaternary surficial deposits, including extensive colluvial, fluvial, glacial, and lacustrine deposits, locally cover all older rocks. Miocene and younger rocks are tilted ≤30° in variable directions. These rocks are cut by several sets of high-angle faults that exhibit a temporal change from conjugate northeast-striking left-lateral and north-striking right-lateral oblique-slip faults in rocks older than about 9 Ma to north- and northwest-striking dip-slip faults in late Miocene rocks. The youngest faults are north-striking normal and northeast-striking left-lateral oblique-slip faults that cut Pliocene-Pleistocene rocks. Numerous hydrothermal systems were active during Miocene magmatism and formed extensive zones of hydrothermally altered rocks and several large mineral deposits, including gold- and silver-rich veins in the Bodie and Aurora mining districts (Vikre and others, in press).

Three-Dimensional Growth of Flexural Slip Fault-Bend and Fault-Propagation Folds and Their Geomorphic Expression

Directory of Open Access Journals (Sweden)

Asdrúbal Bernal

2018-03-01

Full Text Available The three-dimensional growth of fault-related folds is known to be an important process during the development of compressive mountain belts. However, comparatively little is known concerning the manner in which fold growth is expressed in topographic relief and local drainage networks. Here we report results from a coupled kinematic and surface process model of fault-related folding. We consider flexural slip fault-bend and fault-propagation folds that grow in both the transport and strike directions, linked to a surface process model that includes bedrock channel development and hillslope diffusion. We investigate various modes of fold growth under identical surface process conditions and critically analyse their geomorphic expression. Fold growth results in the development of steep forelimbs and gentler, wider backlimbs resulting in asymmetric drainage basin development (smaller basins on forelimbs, larger basins on backlimbs. However, topographies developed above fault-propagation folds are more symmetric than those developed above fault-bend folds as a result of their different forelimb kinematics. In addition, the surface expression of fault-bend and fault-propagation folds depends both on the slip distribution along the fault and on the style of fold growth. When along-strike plunge is a result of slip events with gently decreasing slip towards the fault tips (with or without lateral propagation, large plunge-panel drainage networks are developed at the expense of backpanel (transport-opposing and forepanel (transport-facing drainage basins. In contrast, if the fold grows as a result of slip events with similar displacements along strike, plunge-panel drainage networks are poorly developed (or are transient features of early fold growth and restricted to lateral fold terminations, particularly when the number of propagation events is small. The absence of large-scale plunge-panel drainage networks in natural examples suggests that the

Care around birth, infant and mother health and maternal health investments - Evidence from a nurse strike.

Science.gov (United States)

Kronborg, Hanne; Sievertsen, Hans Henrik; Wüst, Miriam

2016-02-01

Care around birth may impact child and mother health and parental health investments. We exploit the 2008 national strike among Danish nurses to identify the effects of care around birth on infant and mother health (proxied by health care usage) and maternal investments in the health of their newborns. We use administrative data from the population register on 39,810 Danish births in the years 2007-2010 and complementary survey and municipal administrative data on 8288 births in the years 2007-2009 in a differences-in-differences framework. We show that the strike reduced the number of mothers' prenatal midwife consultations, their length of hospital stay at birth, and the number of home visits by trained nurses after hospital discharge. We find that this reduction in care around birth increased the number of child and mother general practitioner (GP) contacts in the first month. As we do not find strong effects of strike exposure on infant and mother GP contacts in the longer run, this result suggests that parents substitute one type of care for another. While we lack power to identify the effects of care around birth on hospital readmissions and diagnoses, our results for maternal health investments indicate that strike-exposed mothers-especially those who lacked postnatal early home visits-are less likely to exclusively breastfeed their child at four months. Thus reduced care around birth may have persistent effects on treated children through its impact on parental investments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mesozoic to Cenozoic tectonic transition process in Zhanhua Sag, Bohai Bay Basin, East China

Science.gov (United States)

Cheng, Yanjun; Wu, Zhiping; Lu, Shunan; Li, Xu; Lin, Chengyan; Huang, Zheng; Su, Wen; Jiang, Chao; Wang, Shouye

2018-04-01

The Zhanhua sag is part of the Bohai Bay intracontinental basin system that has developed since the Mesozoic in East China. The timing of this basin system coincides with the final assembly of East Asia and the development of Western Pacific-type plate margin. Here we use 3-D seismic and core log data to investigate the evolution of this basin and discuss its broad tectonic settings. Our new structural study of Zhanhua sag suggests that there are four major tectonic transitions occurred in the Bohai Bay Basin during Mesozoic and Cenozoic: (1) The first tectonic transition was from stable Craton to thrusting during the Triassic, mainly caused by the South China Block's subduction northward beneath the North China Block, which induced the formation of the NW-striking thrust faults. (2) The second tectonic transition was mainly characterized by a change from compression to extension, which can be further divided into two-stages. At the first stage, two episodes of NW-SE shortening occurred in East Asia during Early-Middle Jurassic and Late Jurassic-earliest Cretaceous, respectively. At the second stage, the extension and left-lateral shearing took place during Early Cretaceous while compression occurred during Late Cretaceous. The NW-striking thrust faults changed to normal faults and the NNE-striking left-lateral strike-slip faults started to influence the eastern part of the basin. (3) The third transition occurred when the NW-SE extension and NNE-striking right-lateral shearing started to form during Paleogene, and the peak deformation happen around 40 Ma due to the change of the subduction direction of Pacific Plate relative to Eurasia Plate. The NE-striking normal faults are the main structure, and the pre-existing NNE-striking strike-slip faults changed from left-lateral to right-lateral. (4) The fourth transition saw the regional subsidence during Neogene, which was probably caused by the India-Asia "Hard collision" between 25 and 20 Ma.

Fault slip and earthquake recurrence along strike-slip faults — Contributions of high-resolution geomorphic data

KAUST Repository

Zielke, Olaf; Klinger, Yann; Arrowsmith, J. Ramon

2015-01-01

to contribute to better-informed models of EQ recurrence and slip-accumulation patterns. After reviewing motivation and background, we outline requirements to successfully reconstruct a fault's offset accumulation pattern from geomorphic evidence. We address

Comparison of foot strike patterns of barefoot and minimally shod runners in a recreational road race

OpenAIRE

Peter Larson

2014-01-01

Background: Previous studies of foot strike patterns of distance runners in road races have typically found that the overwhelming majority of shod runners initially contact the ground on the rearfoot. However, none of these studies has attempted to quantify foot strike patterns of barefoot or minimally shod runners. This study classifies foot strike patterns of barefoot and minimally shod runners in a recreational road race. Methods: High-speed video footage was obtained of 169 barefoot an...

Kinematics of Post-obduction Deformation of the Tertiary Ridge at Al-Khod Village (Muscat, Oman

Directory of Open Access Journals (Sweden)

Andreas Scharf

2016-11-01

Full Text Available Structural investigations in post-obductional Paleocene to Eocene limestones of the Tertiary Ridge reveal a ~1 km long WNW-ESE striking strike-slip fault system within the ridge, consisting of two main sub-parallel, strike-slip faults. Considering the geometry of the Harding Strain Ellipse, the orientation of structures between the two strike-slip faults (e.g., Riedel shears, folds, reverse faults point to left-lateral motion. The abundance of large-scale folds (up to 100 m in wave length and amplitude between the two strike-slip faults led us to the interpretation of transpressive conditions in a first approximation. Moreover, the Tertiary Ridge of the study area consists of three distinct structural domains. The faults of Domain A and C are oriented WNW-ESE, but the trend of the faults in the central Domain B differs by ~10°. The left-lateral strike-slip fault system exists only in Domain B. We propose that the direction of greatest stress during Miocene plate convergence (sigma 1 was oriented 032°/212°. Considering the trend of the strike-slip zone and the orientation of sigma 1, the left-lateral motion must have been transpressive. Sigma 1 is perpendicularly oriented to the domains A and C. Prior to the Miocene D2 compressional event the study area was affected by a D1 extensional event, related to the opening of the Red Sea and the Gulf of Aden or to gravity-driven normal faulting. The D2 compressional/transpressional structures of the Miocene are reactivating the D1 structures of the Oligocene.

Ankle and knee kinetics between strike patterns at common training speeds in competitive male runners.

Science.gov (United States)

Kuhman, Daniel; Melcher, Daniel; Paquette, Max R

2016-01-01

The purpose of this study was to investigate the interaction of foot strike and common speeds on sagittal plane ankle and knee joint kinetics in competitive rear foot strike (RFS) runners when running with a RFS pattern and an imposed forefoot strike (FFS) pattern. Sixteen competitive habitual male RFS runners ran at two different speeds (i.e. 8 and 6 min mile(-1)) using their habitual RFS and an imposed FFS pattern. A repeated measures analysis of variance was used to assess a potential interaction between strike pattern and speed for selected ground reaction force (GRF) variables and, sagittal plane ankle and knee kinematic and kinetic variables. No foot strike and speed interaction was observed for any of the kinetic variables. Habitual RFS yielded a greater loading rate of the vertical GRF, peak ankle dorsiflexor moment, peak knee extensor moment, peak knee eccentric extensor power, peak dorsiflexion and sagittal plane knee range of motion compared to imposed FFS. Imposed FFS yielded greater maximum vertical GRF, peak ankle plantarflexor moment, peak ankle eccentric plantarflexor power and sagittal plane ankle ROM compared to habitual RFS. Consistent with previous literature, imposed FFS in habitual RFS reduces eccentric knee extensor and ankle dorsiflexor involvement but produce greater eccentric ankle plantarflexor action compared to RFS. These acute differences between strike patterns were independent of running speeds equivalent to typical easy and hard training runs in competitive male runners. Current findings along with previous literature suggest differences in lower extremity kinetics between habitual RFS and imposed FFS running are consistent among a variety of runner populations.

Structured methods and striking moments: using question sequences in "living" ways.

Science.gov (United States)

Lowe, Roger

2005-03-01

This article draws together two seemingly incompatible practices in social constructionist therapies: the use of structured questioning methods (associated with solution-focused and narrative therapies) and the poetic elaboration of "striking moments" (associated with conversational therapies). To what extent can we value and use both styles of practice? Beginning with practitioners' concerns about the use of structured question sequences, I explore possibilities for resituating these methods in different conceptual and metaphorical frames, selectively drawing on ideas from the philosophy of striking moments. The aim is not to reduce one therapeutic style to another, but to encourage the teaching and practice of structured methods in more creative, improvisational, and "living" ways.

Foot strike pattern in preschool children during running: sex and shod-unshod differences.

Science.gov (United States)

Latorre-Román, Pedro Á; Párraga-Montilla, Juan A; Guardia-Monteagudo, Ignacio; García-Pinillos, Felipe

2018-04-01

This study aims to determine the foot strike patterns (FSPs) and neutral support (no inversion [INV]/eversion [EVE] and no foot rotation) in preschool children, as well as to determine the influence of shod/unshod conditions and sex. A total of 1356 children aged 3-6 years (673 boys and 683 girls) participated in this study. A sagittal and frontal-plane video (240 Hz) was recorded using a high-speed camcorder to record the following variables: rearfoot strike (RFS), midfoot strike (MFS), forefoot strike (FFS), inversion/ eversion (INV/EVE) and foot rotation on initial contact. There were no between-sex significant differences in both shod and unshod conditions in RFS. In the unshod condition, there was a significant reduction (p < 0.001) of RFS prevalence in both boys (shod condition = 44.2% vs. 34.7% unshod condition) and girls (shod condition = 48.5% vs. 36.1% unshod condition). As for neutral support, there were no between-sex differences in both shod and unshod conditions or in the shod-unshod comparison. In preschool children, no between-sex differences were found in relation to prevalence of RFS and neutral support (no INV/EVE). Shod running alters FSP of running barefoot, producing a significant increase of RFS prevalence.

A lightning strike to the head causing a visual cortex defect with simple and complex visual hallucinations

Science.gov (United States)

Kleiter, Ingo; Luerding, Ralf; Diendorfer, Gerhard; Rek, Helga; Bogdahn, Ulrich; Schalke, Berthold

2009-01-01

The case of a 23-year-old mountaineer who was hit by a lightning strike to the occiput causing a large central visual field defect and bilateral tympanic membrane ruptures is described. Owing to extreme agitation, the patient was sent into a drug-induced coma for 3 days. After extubation, she experienced simple and complex visual hallucinations for several days, but otherwise largely recovered. Neuropsychological tests revealed deficits in fast visual detection tasks and non-verbal learning and indicated a right temporal lobe dysfunction, consistent with a right temporal focus on electroencephalography. At 4 months after the accident, she developed a psychological reaction consisting of nightmares, with reappearance of the complex visual hallucinations and a depressive syndrome. Using the European Cooperation for Lightning Detection network, a meteorological system for lightning surveillance, the exact geographical location and nature of the lightning strike were retrospectively retraced PMID:21734915

Skin Cancer Can Strike Anyone | NIH MedlinePlus the Magazine

Science.gov (United States)

... of this page please turn Javascript on. Feature: Skin Cancer Skin Cancer Can Strike Anyone Past Issues / Summer 2013 ... removed. That is the most common form of skin cancer and not as dangerous as melanoma. Photo: ...

Structural analysis of hanging wall and footwall blocks within the Río Guanajibo fold-and-thrust belt in Southwest Puerto Rico

Science.gov (United States)

Laó-Dávila, Daniel A.; Llerandi-Román, Pablo A.

2017-01-01

The Río Guanajibo fold-and-thrust belt (RGFT), composed of Cretaceous serpentinite and volcano-sedimentary rocks, represents the deformation front of a contractional event in SW Puerto Rico during the Paleogene. Previous studies inferred structural and stratigraphic relationships from poorly exposed outcrops. New road cuts exposed the Yauco (YF) and El Rayo Formations (ERF) providing insights on the deformation of the hanging wall and footwall. We described the nature and orientation of faults and folds and analyzed the kinematic indicators to characterize the deformation. The YF occurs in the hanging wall and shows a sequence of folded, medium-bedded mudstone and thinly bedded shale and sandstone. Major folds strike NW-SE and are gentle with steeply inclined axial planes and sub-horizontal fold axes. Minor folds are open with moderately inclined axial planes and gently to moderately inclined SE-plunging fold axes. NW-SE striking reverse and thrust faults cut layers and show movement to the SW. Steep left-lateral faults strike NW-SE and NE-SW, and smaller right-lateral strike-slip faults strike NNE-SSW. At the footwall, the ERF consists of bioclastic limestone and polymictic orthoconglomerates and paraconglomerates. Reverse and strike-slip faults cut along lithological contacts. Results suggest that the hanging wall and footwall accommodated strain along preexisting weaknesses, which are dependent on lithology and sedimentary structures. The kinematic analysis suggests that shortening in the NE-SW direction was partitioned between folding and interlayer shortening, accommodated by flexural slip, and reverse and left-lateral faults that resulted from contraction. The RGFT represents the Paleogene back arc deformation of a bivergent thrust system.

Three models of labor conflict in chile: the weight of the economy, trade union organization, and work regime in illegal strike tendencies

Directory of Open Access Journals (Sweden)

Rodrigo Medel Sierralta

2017-07-01

Full Text Available From the return to democracy to the present, illegal strikes have acquired a prominent role in Chile’s labor conflicts, mainly due to the fact that many more workers mobilize, compared to those who participate in legal strikes. Nevertheless, existing studies on the subject focus on descriptions and general tendencies, thus neglecting the in-depth analysis of the factors determining the specific occurrence of the extralegal strikes. Consequently, the factors that might be contributing to the possibility of illegal strikes remain unknown. If labor strikes are construed as analytical events that are fundamental in order to understand power relations in capitalist enterprises, the review of the international literature on the subject helps us solve that problem, since it proposes statistical analysis models to study the economy at the national level (economic cycles, trade union organization (membership and size of unions, and work regime (fragmentation and job insecurity, as well as a further company-level analysis of the last two models. On the basis of statistics regarding the strikes that took place in Chile between 1990 and 2015 and a binary logistic regression analysis, we analyzed the weight of each one of those statistical models separately and that of all of them taken together, in the private sector of the economy (in which it is possible to opt for one or the other strike modality in the Chilean case. The results show that the trade union organization and the work regime models have a greater power to determine illegal strikes, and that the economic model loses meaning when its variables are included in the complete model. Finally, the article presents the conclusions regarding the relevance of the distinction between legal and illegal strikes for the Chilean case, in terms of workers that not only represent subjects without rights, but also actors with a certain autonomy regarding legality. In this sense, these

Acute neuromuscular responses to short and long roundhouse kick striking paces in professional Muay Thai fighters.

Science.gov (United States)

Cimadoro, Giuseppe; Mahaffey, Ryan; Babault, Nicolas

2018-04-04

Muay Thai fighters strongly rely on the use of the roundhouse kick due to its effectiveness (i.e. power) and implications on the final score. Therefore, different striking tempos at full power are used during training as a method to enhance kicking power. However, the neuromuscular responses are unknown. Thus, the goal of this study was to investigate neuromuscular responses to a single bout of shorter (every second = H1) and longer (every 3s = H3) kick striking time intervals, measured with the countermovement jump (CMJ). Nine professional Muay Thai fighters participated in this randomized, cross-over trial. CMJs were measured on force plates before and after (post 0min, post 5min, post 10min, post 20min and post 30min) two striking (1set x 20reps) conditions (H1; H3). Although no difference was observed between H1 and H3 values, neuromuscular fatigue parameters displayed different patterns over time. CMJ height decreased immediately after H3 striking (PMuay Thai and conditioning coaches should focus on hard striking with both long and slow pacing during specific heavy bag or pad work.

2018 NDIA Precision Strike Annual Review (PSAR-18)

Science.gov (United States)

2018-03-20

Planning Agenda as of 9 MAR 18 Ginny Sniegon: 703-575-6653 PRECISION STRIKE ANNUAL REVIEW (PSAR-18) 20 MARCH 2018...Ginny Sniegon PSA Programs Vice-Chair: Captain David “Jumbo” Baird, USN Annual Review Chair: Kurt Chankaya Congressional & William J. Perry...0745 PSA ANNUAL REVIEW WELCOME: Ken Masson—PSA Chairman 0755 PSAR-18 OPENING REMARKS: Kurt Chankaya—PSAR-18 Event Chair 0800 CONGRESSIONAL

Characterization of Foot-Strike Patterns: Lack of an Association With Injuries or Performance in Soldiers.

Science.gov (United States)

Warr, Bradley J; Fellin, Rebecca E; Sauer, Shane G; Goss, Donald L; Frykman, Peter N; Seay, Joseph F

2015-07-01

Characterize the distribution of foot-strike (FS) patterns in U.S. Army Soldiers and determine if FS patterns are related to self-reported running injuries and performance. 341 male Soldiers from a U.S. Army Combined Arms Battalion ran at their training pace for 100 meters, and FSs were recorded in the sagittal plane. Participants also completed a survey related to training habits, injury history, and run times. Two researchers classified FS patterns as heel strike (HS) or nonheel strike (NHS, combination of midfoot strike and forefoot strike patterns). Two clinicians classified the musculoskeletal injuries as acute or overuse. The relationship of FS type with two-mile run time and running-related injury was analyzed (p ≤ 0.05). The Soldiers predominately landed with an HS (87%) and only 13% were characterized as NHS. Running-related injury was similar between HS (50.3%) and NHS (55.6%) patterns (p = 0.51). There was no difference (p = 0.14) between overuse injury rates between an HS pattern (31.8%) and an NHS pattern (31.0%). Two-mile run times were also similar, with both groups averaging 14:48 minutes. Soldiers were mostly heel strikers (87%) in this U.S. Army Combined Arms Battalion. Neither FS pattern was advantageous for increased performance or decreased incidence of running-related injury. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Analyzing structural variations along strike in a deep-water thrust belt

Science.gov (United States)

Totake, Yukitsugu; Butler, Robert W. H.; Bond, Clare E.; Aziz, Aznan

2018-03-01

We characterize a deep-water fold-thrust arrays imaged by a high-resolution 3D seismic dataset in the offshore NW Borneo, Malaysia, to understand the kinematics behind spatial arrangement of structural variations throughout the fold-thrust system. The seismic volume used covers two sub-parallel fold trains associated with a series of fore-thrusts and back-thrusts. We measured fault heave, shortening value, fold geometries (forelimb dip, interlimb angle and crest depth) along strike in individual fold trains. Heave plot on strike projection allows to identify individual thrust segments showing semi-elliptical to triangular to bimodal patterns, and linkages of these segments. The linkage sites are marked by local minima in cumulative heave. These local heave minima are compensated by additional structures, such as small imbricate thrusts and tight folds indicated by large forelimb dip and small interlimb angle. Complementary profiles of the shortening amount for the two fold trains result in smoother gradient of total shortening across the structures. We interpret this reflects kinematic interaction between two fold-thrust trains. This type of along-strike variation analysis provides comprehensive understanding of a fold-thrust system and may provide an interpretative strategy for inferring the presence of complex multiple faults in less well-imaged parts of seismic volumes.

Striking dynamics and kinetic properties of boxing and MMA gloves

Directory of Open Access Journals (Sweden)

Benjamin Lee

2014-08-01

Full Text Available With the growing popularity of Mixed Martial Arts (MMA as a competitive sport, questions regarding the dynamic response and properties of MMA gloves arise. High-energy impacts from punches are very similar to boxing yet MMA competition requires the use of 4 oz fingerless glove, compared to the larger full enclosure boxing glove. This work assessed the kinetic properties and strike dynamics of MMA gloves and compared findings with traditional boxing gloves. Gloves mounted on a molded fist were impacted repetitively on an instrumental anvil designed for impact, over a 5 hour period resulting in 10,000 continuous and consistent strikes. Kinetic data from impacts were sampled at the beginning of the data collection and subsequently every 30 minutes (every 1,000 strikes. MMA gloves produced 4-5 times greater peak force and 5 times faster load rate compared to the boxing glove. However, MMA gloves also showed signs of material fatigue, with peak force increasing by 35% and rate of loading increasing by 60% over the duration of the test. Boxing glove characteristics did deteriorate but to a lesser extent. In summary, the kinetic properties of MMA glove differed substantially from the boxing glove resulting in impacts characterized by higher peak forces and more rapid development of force. Material properties including stiffness and thickness play a role in the kinetic characteristics upon impact, and can be inferred to alter injury mechanisms of blunt force trauma.

Spatial and Temporal Variations in Slip Partitioning During Oblique Convergence Experiments

Science.gov (United States)

Beyer, J. L.; Cooke, M. L.; Toeneboehn, K.

2017-12-01

Physical experiments of oblique convergence in wet kaolin demonstrate the development of slip partitioning, where two faults accommodate strain via different slip vectors. In these experiments, the second fault forms after the development of the first fault. As one strain component is relieved by one fault, the local stress field then favors the development of a second fault with different slip sense. A suite of physical experiments reveals three styles of slip partitioning development controlled by the convergence angle and presence of a pre-existing fault. In experiments with low convergence angles, strike-slip faults grow prior to reverse faults (Type 1) regardless of whether the fault is precut or not. In experiments with moderate convergence angles, slip partitioning is dominantly controlled by the presence of a pre-existing fault. In all experiments, the primarily reverse fault forms first. Slip partitioning then develops with the initiation of strike-slip along the precut fault (Type 2) or growth of a secondary reverse fault where the first fault is steepest. Subsequently, the slip on the first fault transitions to primarily strike-slip (Type 3). Slip rates and rakes along the slip partitioned faults for both precut and uncut experiments vary temporally, suggesting that faults in these slip-partitioned systems are constantly adapting to the conditions produced by slip along nearby faults in the system. While physical experiments show the evolution of slip partitioning, numerical simulations of the experiments provide information about both the stress and strain fields, which can be used to compute the full work budget, providing insight into the mechanisms that drive slip partitioning. Preliminary simulations of precut experiments show that strain energy density (internal work) can be used to predict fault growth, highlighting where fault growth can reduce off-fault deformation in the physical experiments. In numerical simulations of uncut experiments with a

Counterproliferation Strategy: The Role of Preventive War, Preventive Strikes, and Interdiction

National Research Council Canada - National Science Library

Rak, Claire

2003-01-01

This thesis analyzes the potential effectiveness of preventive war, preventive strikes, and interdiction as tools for the United States to counter the proliferation of weapons of mass destruction (WMD...

Rozšíření produktové řady značky Lucky Strike

OpenAIRE

Boháč, Radim

2012-01-01

The aim of this thesis is a detailed analysis of marketing plan for line extension of Lucky Strike on Czech tobacco market. The theoretical part will be focused on the analysis of a brand, proccess of strategic brand management and marketing planning. The practical part is dedicated to positioning and marketing plan of Lucky Strike.

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Pseudotachylytes, as well as the country rock, bear the evidence of conjugate strike slip shearing along NNE–SSW and NW–SE directions, suggesting an N–S compression. The Gangavalli Shear Zone represents the NNE–SSW fault of the conjugate system along which a right lateral shear has produced seismic slip motion ...

The lightning striking probability for offshore wind turbine blade with salt fog contamination

Science.gov (United States)

Li, Qingmin; Ma, Yufei; Guo, Zixin; Ren, Hanwen; Wang, Guozheng; Arif, Waqas; Fang, Zhiyang; Siew, Wah Hoon

2017-08-01

The blades of an offshore wind turbine are prone to be adhered with salt fog after long-time exposure in the marine-atmosphere environment, and salt fog reduces the efficiency of the lightning protection system. In order to study the influence of salt fog on lightning striking probability (LSP), the lightning discharge process model for the wind turbine blade is adopted in this paper considering the accumulation mechanism of surface charges around the salt fog area. The distribution of potential and electric field with the development of the downward leader is calculated by COMSOL Multiphysics LiveLink for MATLAB. A quantitative characterization method is established to calculate the LSP base on the average electric field before the return stroke and the LSP distribution of the blade is shown in the form of a graphic view. The simulation results indicate that the receptor and conductor area close to the receptor area are more likely to get struck by lightning, and the LSP increases under the influence of salt fog. The validity of the model is verified by experiments. Furthermore, the receptor can protect the blade from lightning strikes effectively when the lateral distance between the rod electrode and receptor is short. The influence of salt fog on LSP is more obvious if salt fog is close to the receptor or if the scope of salt fog area increases.

Preliminary slip history of the 2002 Denali earthquake

Science.gov (United States)

Ji, C.; Helmberger, D.; Wald, D.

2002-12-01

Rapid slip histories for the 2002 Denali earthquake were derived from the IRIS global data before geologists arrived in the field. We were able to predict many of the features they observed. Three models were produced indicating a step-wise improvement in matching the waveform data applying a formalism discussed in Ji et al. (2002). The first model referred to as Phase I is essentially an automated solution where a simple fault plane (300 km long) is fixed agreeing with CMT (Harvard) solution (strike 298 dip =86) assuming the PDE epicenter. The fit to the initial P waves does not work since they do not display a strike-slip polarity pattern. Thus, to continue we added a thrusting event (Phase II) following roughly the fault geometry of the Denali fault based on DEM topography map. While this produced some improvements, major misfits still remained. Before proceeding with Phase III, we did some homework on a foreshock, the Mw=6.7 Nenana event. After modeling this strike-slip event as a distributed fault, we used this relatively simple event to calibrate paths where shifts in P-waves and SH-waves ranged up to 4 and 8 sec respectively. Applying these corrections revealed some discrepancies in the rupture initiation. To produce a consistent picture requires 4 fault segments A, B, C and D. A weak rupture may initiate on a strike-slip Denali fault branch A at a depth of 10 km where a low angle thrust fault plane B intersects A. After about 2 sec, a major event occurred on plane B (strike=221, dip=35) and dominated the rupture of next 8 sec. When rupture B reaches the surface at about 10 sec after initiation, the major portion of the Denali fault (segment C) ruptured eastward with a relatively fast velocity (3 km/sec) producing a large slip concentration (up to 9 m at a depth of 10 km). The surface slip is about 7 km at a 20 km long segment. This feature is near the intersection of the Denali fault and the Totichunda fault (branch D). The rupture on D is relatively

Biomechanical Differences of Foot-Strike Patterns During Running: A Systematic Review With Meta-analysis.

Science.gov (United States)

Almeida, Matheus O; Davis, Irene S; Lopes, Alexandre D

2015-10-01

Systematic review with meta-analysis. To determine the biomechanical differences between foot-strike patterns used when running. Strike patterns during running have received attention in the recent literature due to their potential mechanical differences and associated injury risks. Electronic databases (MEDLINE, Embase, LILACS, SciELO, and SPORTDiscus) were searched through July 2014. Studies (cross-sectional, case-control, prospective, and retrospective) comparing the biomechanical characteristics of foot-strike patterns during running in distance runners at least 18 years of age were included in this review. Two independent reviewers evaluated the risk of bias. A meta-analysis with a random-effects model was used to combine the data from the included studies. Sixteen studies were included in the final analysis. In the meta-analyses of kinematic variables, significant differences between forefoot and rearfoot strikers were found for foot and knee angle at initial contact and knee flexion range of motion. A forefoot-strike pattern resulted in a plantar-flexed ankle position and a more flexed knee position, compared to a dorsiflexed ankle position and a more extended knee position for the rearfoot strikers, at initial contact with the ground. In the comparison of rearfoot and midfoot strikers, midfoot strikers demonstrated greater ankle dorsiflexion range of motion and decreased knee flexion range of motion compared to rearfoot strikers. For kinetic variables, the meta-analysis revealed that rearfoot strikers had higher vertical loading rates compared to forefoot strikers. There are differences in kinematic and kinetic characteristics between foot-strike patterns when running. Clinicians should be aware of these characteristics to help in the management of running injuries and advice on training.

Effects of foot strike on low back posture, shock attenuation, and comfort in running.

Science.gov (United States)

Delgado, Traci L; Kubera-Shelton, Emilia; Robb, Robert R; Hickman, Robbin; Wallmann, Harvey W; Dufek, Janet S

2013-03-01

Barefoot running (BF) is gaining popularity in the running community. Biomechanical changes occur with BF, especially when initial contact changes from rearfoot strike (RFS) to forefoot strike (FFS). Changes in lumbar spine range of motion (ROM), particularly involving lumbar lordosis, have been associated with increased low back pain. However, it is not known if changing from RFS to FFS affects lumbar lordosis or low back pain. The purpose of this study was to determine whether a change from RFS to FFS would change lumbar lordosis, influence shock attenuation, or change comfort levels in healthy recreational/experienced runners. Forty-three subjects performed a warm-up on the treadmill where a self-selected foot strike pattern was determined. Instructions on running RFS/FFS were taught, and two conditions were examined. Each condition consisted of 90 s of BF with RFS or FFS, order randomly assigned. A comfort questionnaire was completed after both conditions. Fifteen consecutive strides from each condition were extracted for analyses. Statistically significant differences between FFS and RFS shock attenuation (P strike from RFS to FFS decreased overall ROM in the lumbar spine but did not make a difference in flexion or extension in which the lumbar spine is positioned. Shock attenuation was greater in RFS. RFS was perceived a more comfortable running pattern.

The Distribution of Cloud to Ground Lightning Strike Intensities and Associated Magnetic Inductance Fields Near the Kennedy Space Center

Science.gov (United States)

Burns, Lee; Decker, Ryan

2005-01-01

Lightning strike location and peak current are monitored operationally in the Kennedy Space Center (KSC) Cape Canaveral Air Force Station (CCAFS) area by the Cloud to Ground Lightning Surveillance System (CGLSS). The present study compiles ten years worth of CGLSS data into a database of near strikes. Using shuffle launch platform LP39A as a convenient central point, all strikes recorded within a 20-mile radius for the period of record O R ) from January 1, 1993 to December 31,2002 were included in the subset database. Histograms and cumulative probability curves are produced for both strike intensity (peak current, in kA) and the corresponding magnetic inductance fields (in A/m). Results for the full POR have application to launch operations lightning monitoring and post-strike test procedures.

A parabolic variational inequality arising from the valuation of strike reset options

Science.gov (United States)

Yang, Zhou; Yi, Fahuai; Dai, Min

A strike reset option is an option that allows its holder to reset the strike price to the prevailing underlying asset price at a moment chosen by the holder. The pricing model of the option can be formulated as a one-dimensional parabolic variational inequality, or equivalently, a free boundary problem, where the free boundary just corresponds to the optimal reset strategy adopted by the holder of the option. This paper is concerned with the theoretical analysis of the model. The existence and uniqueness of the solution are established. Furthermore, we study properties of the free boundary. The monotonicity and C smoothness of the free boundary are proven in some situations.

Ductile bookshelf faulting: A new kinematic model for Cenozoic deformation in northern Tibet

Science.gov (United States)

Zuza, A. V.; Yin, A.

2013-12-01

It has been long recognized that the most dominant features on the northern Tibetan Plateau are the >1000 km left-slip strike-slip faults (e.g., the Atyn Tagh, Kunlun, and Haiyuan faults). Early workers used the presence of these faults, especially the Kunlun and Haiyuan faults, as evidence for eastward lateral extrusion of the plateau, but their low documented offsets--100s of km or less--can not account for the 2500 km of convergence between India and Asia. Instead, these faults may result from north-south right-lateral simple shear due to the northward indentation of India, which leads to the clockwise rotation of the strike-slip faults and left-lateral slip (i.e., bookshelf faulting). With this idea, deformation is still localized on discrete fault planes, and 'microplates' or blocks rotate and/or translate with little internal deformation. As significant internal deformation occurs across northern Tibet within strike-slip-bounded domains, there is need for a coherent model to describe all of the deformational features. We also note the following: (1) geologic offsets and Quaternary slip rates of both the Kunlun and Haiyuan faults vary along strike and appear to diminish to the east, (2) the faults appear to kinematically link with thrust belts (e.g., Qilian Shan, Liupan Shan, Longmen Shan, and Qimen Tagh) and extensional zones (e.g., Shanxi, Yinchuan, and Qinling grabens), and (3) temporal relationships between the major deformation zones and the strike-slip faults (e.g., simultaneous enhanced deformation and offset in the Qilian Shan and Liupan Shan, and the Haiyuan fault, at 8 Ma). We propose a new kinematic model to describe the active deformation in northern Tibet: a ductile-bookshelf-faulting model. With this model, right-lateral simple shear leads to clockwise vertical axis rotation of the Qaidam and Qilian blocks, and left-slip faulting. This motion creates regions of compression and extension, dependent on the local boundary conditions (e.g., rigid

An evaluation method for tornado missile strike probability with stochastic correction

Energy Technology Data Exchange (ETDEWEB)

Eguchi, Yuzuru; Murakami, Takahiro; Hirakuchi, Hiromaru; Sugimoto, Soichiro; Hattori, Yasuo [Nuclear Risk Research Center (External Natural Event Research Team), Central Research Institute of Electric Power Industry, Abiko (Japan)

2017-03-15

An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, QV(r), of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of QV(r) and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure.

An evaluation method for tornado missile strike probability with stochastic correction

International Nuclear Information System (INIS)

Eguchi, Yuzuru; Murakami, Takahiro; Hirakuchi, Hiromaru; Sugimoto, Soichiro; Hattori, Yasuo

2017-01-01

An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, QV(r), of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of QV(r) and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure

Strain analysis and stratigraphic status of Nongkhya, Sumer and ...

Indian Academy of Sciences (India)

effect of right and left lateral strike slip movement of Sumer conglomerate at Sumer and Adabasti points, respectively. .... A mere one or .... imagery, hill morphology and isolated exposure of ..... Dasgupta, Associate Editor of the Journal, for his.

Reflections on the health workers' strike at Malawi's major tertiary hospital, QECH, Blantyre, 2001: a case study.

Science.gov (United States)

Muula, A S; Phiri, A

2003-03-01

Health workers and support staff at Malawi's major referral hospital, the Queen Elizabeth Central Hospital, Blantyre, were on strike between 5th and 19th October 2001. The health workers' grievances included: lack of risk allowances; poor professional allowances; low salaries; and low housing allowances. The strike resulted in almost total closure of the 1500-bed hospital; only the burns and orthopaedic wards continued to serve patients. Volunteer staff, comprising the Red Cross, and nursing and medical students provided services. Verbal and written threats by the authorities had minimal effect on terminating the strike; rather, they encouraged the resolve to continue with the industrial action. We report aspects of the genesis, progress and resolution of the strike. Although not much seems to have been achieved, both the employer and the workers need to draw lessons from the experience.

Foot strike patterns of runners at the 15-km point during an elite-level half marathon.

Science.gov (United States)

Hasegawa, Hiroshi; Yamauchi, Takeshi; Kraemer, William J

2007-08-01

There are various recommendations by many coaches regarding foot landing techniques in distance running that are meant to improve running performance and prevent injuries. Several studies have investigated the kinematic and kinetic differences between rearfoot strike (RFS), midfoot strike (MFS), and forefoot strike (FFS) patterns at foot landing and their effects on running efficiency on a treadmill and over ground conditions. However, little is known about the actual condition of the foot strike pattern during an actual road race at the elite level of competition. The purpose of the present study was to document actual foot strike patterns during a half marathon in which elite international level runners, including Olympians, compete. Four hundred fifteen runners were filmed by 2 120-Hz video cameras in the height of 0.15 m placed at the 15.0-km point and obtained sagittal foot landing and taking off images for 283 runners. Rearfoot strike was observed in 74.9% of all analyzed runners, MFS in 23.7%, and FFS in 1.4%. The percentage of MFS was higher in the faster runners group, when all runners were ranked and divided into 50 runner groups at the 15.0-km point of the competition. In the top 50, which included up to the 69th place runner in actual order who passed the 15-km point at 45 minutes, 53 second (this speed represents 5.45 m x s(-1), or 15 minutes, 17 seconds per 5 km), RFS, MFS, and FFS were 62.0, 36.0, and 2.0%, respectively. Contact time (CT) clearly increased for the slower runners, or the placement order increased (r = 0.71, p strike was observed in 42% of all runners. The percentage of INV for MFS was higher than for RFS and FFS (62.5, 32.0, and 50%, respectively). The CT with INV for MFS + FFS was significantly shorter than the CT with and without INV for RFS. Furthermore, the CT with INV was significantly shorter than push-off time without INV for RFS. The findings of this study indicate that foot strike patterns are related to running speed. The

Rupture geometry and slip distribution of the 2016 January 21st Ms6.4 Menyuan, China earthquake

Science.gov (United States)

Zhou, Y.

2017-12-01

On 21 January 2016, an Ms6.4 earthquake stroke Menyuan country, Qinghai Province, China. The epicenter of the main shock and locations of its aftershocks indicate that the Menyuan earthquake occurred near the left-lateral Lenglongling fault. However, the focal mechanism suggests that the earthquake should take place on a thrust fault. In addition, field investigation indicates that the earthquake did not rupture the ground surface. Therefore, the rupture geometry is unclear as well as coseismic slip distribution. We processed two pairs of InSAR images acquired by the ESA Sentinel-1A satellite with the ISCE software, and both ascending and descending orbits were included. After subsampling the coseismic InSAR images into about 800 pixels, coseismic displacement data along LOS direction are inverted for earthquake source parameters. We employ an improved mixed linear-nonlinear Bayesian inversion method to infer fault geometric parameters, slip distribution, and the Laplacian smoothing factor simultaneously. This method incorporates a hybrid differential evolution algorithm, which is an efficient global optimization algorithm. The inversion results show that the Menyuan earthquake ruptured a blind thrust fault with a strike of 124°and a dip angle of 41°. This blind fault was never investigated before and intersects with the left-lateral Lenglongling fault, but the strikes of them are nearly parallel. The slip sense is almost pure thrusting, and there is no significant slip within 4km depth. The max slip value is up to 0.3m, and the estimated moment magnitude is Mw5.93, in agreement with the seismic inversion result. The standard error of residuals between InSAR data and model prediction is as small as 0.5cm, verifying the correctness of the inversion results.

ELECTROMYOGRAPHIC STUDY OF A SEQUENCE OF YAU-MAN KUNG FU PALM STRIKES WITH AND WITHOUT IMPACT

Directory of Open Access Journals (Sweden)

Osmar Pinto Neto

2007-10-01

Full Text Available In martial arts and contact sports, strikes are often trained in two different ways: with and without impacts. This study aims to compare the electromyographical activity (EMG of the triceps brachii (TB, biceps brachii (BB and brachioradialis (BR muscles during strikes with and without impacts. Eight Yau-Man Kung Fu practitioners participated in the experiment. Each participant performed 5 sequences of 5 consecutive KF Yau-Man palm strikes with no impact intercalated with 5 sequences of 5 repetitions targeting a KF training shield. Surface EMG signals were obtained from the TB, BB, and RB for 3.0 seconds using an eight-channel module with a total amplifier gain of 2000 and sampled at 3500 Hz. The EMG analyses were done in the time (rms and frequency (wavelet domains. For the frequency domain, Morlet wavelet power spectra were obtained and an original method was used to quantify statistically significant regions on the power spectra. The results both in the time and frequency domains indicate a higher TB and BR muscle activity for the strikes with impacts. No significant difference was found for the BB in the two different scenarios. In addition, the results show that the wavelet power spectra pattern for the three analysed muscles obtained from the strikes with and without impacts were similar

Lateral Offset Quality Rating along Low Slip Rate Faults: Application to the Alhama de Murcia Fault (SE Iberian Peninsula

Directory of Open Access Journals (Sweden)

Marta Ferrater

2015-11-01

Full Text Available Seismic hazard assessment of strike-slip faults is based partly on the identification and mapping of landforms laterally offset due to fault activity. The characterization of these features affected by slow-moving faults is challenging relative to studies emphasizing rapidly slipping faults. We propose a methodology for scoring fault offsets based on subjective and objective qualities. We apply this methodology to the Alhama de Murcia fault (SE Iberian Peninsula where we identify 138 offset features that we mapped on a high-resolution (0.5 × 0.5 m pixel size Digital Elevation Model (DEM. The amount of offset, the uncertainty of the measurement, the subjective and objective qualities, and the parameters that affect objective quality are independent variables, suggesting that our methodological scoring approach is good. Based on the offset measurements and qualifications we calculate the Cumulative Offset Probability Density (COPD for the entire fault and for each fault segment. The COPD for the segments differ from each other. Tentative interpretation of the COPDs implies that the slip rate varies from one segment to the other (we assume that channels with the same amount of offset were incised synchronously. We compare the COPD with climate proxy curves (aligning using the very limited age control to test if entrenchment events are coincident with climatic changes. Channel incision along one of the traces in Lorca-Totana segment may be related to transitions from glacial to interglacial periods.

When the Corporate Storm Strikes the Academy: Faculty Response Required

Science.gov (United States)

DeBoy, James L.

2015-01-01

When the corporate storm strikes the academy, faculty must be willing and able to repel administrative assaults upon academic freedom, shared governance, and tenure. This paper will describe the on-going clash between administrators who embrace the corporate mindset and faculty who cherish traditions of shared governance and collegial…

Update Direct-Strike Lightning Environment for Stockpile-to-Target Sequence

International Nuclear Information System (INIS)

Uman, M.A.; Rakov, V.A.; Elisme, J.O.; Jordan, D.M.; Biagi, C.J.; Hill, J.D.

2008-01-01

The University of Florida has surveyed all relevant publications reporting lightning characteristics and presents here an up-to-date version of the direct-strike lightning environment specifications for nuclear weapons published in 1989 by R. J. Fisher and M. A. Uman. Further, we present functional expressions for current vs. time, current derivative vs. time, second current derivative vs. time, charge transfer vs. time, and action integral (specific energy) vs. time for first return strokes, for subsequent return strokes, and for continuing currents; and we give sets of constants for these expressions so that they yield approximately the median and extreme negative lightning parameters presented in this report. Expressions for the median negative lightning waveforms are plotted. Finally, we provide information on direct-strike lightning damage to metals such as stainless steel, which could be used as components of storage containers for nuclear waste materials; and we describe UF's new experimental research program to add to the sparse data base on the properties of positive lightning. Our literature survey, referred to above, is included in four Appendices. The following four sections (II, III, IV, and V) of this final report deal with related aspects of the research: Section II. Recommended Direct-Strike Median and Extreme Parameters; Section III. Time-Domain Waveforms for First Strokes, Subsequent Strokes, and Continuing Currents; Section IV. Damage to Metal Surfaces by Lightning Currents; and Section V. Measurement of the Characteristics of Positive Lightning. Results of the literature search used to derive the material in Section II and Section IV are found in the Appendices: Appendix 1. Return Stroke Current, Appendix 2. Continuing Current, Appendix 3. Positive Lightning, and Appendix 4. Lightning Damage to Metal Surfaces

[Lightning strikes and lightning injuries in prehospital emergency medicine. Relevance, results, and practical implications].

Science.gov (United States)

Hinkelbein, J; Spelten, O; Wetsch, W A

2013-01-01

Up to 32.2% of patients in a burn center suffer from electrical injuries. Of these patients, 2-4% present with lightning injuries. In Germany, approximately 50 people per year are injured by a lightning strike and 3-7 fatally. Typically, people involved in outdoor activities are endangered and affected. A lightning strike usually produces significantly higher energy doses as compared to those in common electrical injuries. Therefore, injury patterns vary significantly. Especially in high voltage injuries and lightning injuries, internal injuries are of special importance. Mortality ranges between 10 and 30% after a lightning strike. Emergency medical treatment is similar to common electrical injuries. Patients with lightning injuries should be transported to a regional or supraregional trauma center. In 15% of all cases multiple people may be injured. Therefore, it is of outstanding importance to create emergency plans and evacuation plans in good time for mass gatherings endangered by possible lightning.

The oscillatory behavior of the CoM facilitates mechanical energy balance between push-off and heel strike.

Science.gov (United States)

Kim, Seyoung; Park, Sukyung

2012-01-10

Humans use equal push-off and heel strike work during the double support phase to minimize the mechanical work done on the center of mass (CoM) during the gait. Recently, a step-to-step transition was reported to occur over a period of time greater than that of the double support phase, which brings into question whether the energetic optimality is sensitive to the definition of the step-to-step transition. To answer this question, the ground reaction forces (GRFs) of seven normal human subjects walking at four different speeds (1.1-2.4 m/s) were measured, and the push-off and heel strike work for three differently defined step-to-step transitions were computed based on the force, work, and velocity. To examine the optimality of the work and the impulse data, a hybrid theoretical-empirical analysis is presented using a dynamic walking model that allows finite time for step-to-step transitions and incorporates the effects of gravity within this period. The changes in the work and impulse were examined parametrically across a range of speeds. The results showed that the push-off work on the CoM was well balanced by the heel strike work for all three definitions of the step-to-step transition. The impulse data were well matched by the optimal impulse predictions (R(2)>0.7) that minimized the mechanical work done on the CoM during the gait. The results suggest that the balance of push-off and heel strike energy is a consistent property arising from the overall gait dynamics, which implies an inherited oscillatory behavior of the CoM, possibly by spring-like leg mechanics. Copyright © 2011 Elsevier Ltd. All rights reserved.

Magmatic control along a strike-slip volcanic arc: The central Aeolian arc (Italy)

KAUST Repository

Ruch, Joel; Vezzoli, L.; De Rosa, R.; Di Lorenzo, R.; Acocella, V

2016-01-01

-slip motion; consistent with an E-W extension direction, with minor dextral and sinistral shear. Our data highlight six eruptive periods during the last 55 ka, which allow considering both islands as a single magmatic system, in which tectonic and magmatic

Structure of the Hat Creek graben region: Implications for the structure of the Hat Creek graben and transfer of right-lateral shear from the Walker Lane north of Lassen Peak, northern California, from gravity and magnetic anomalies

Science.gov (United States)

Langenheim, Victoria; Jachens, Robert C.; Clynne, Michael A.; Muffler, L. J. Patrick

2016-01-01

Interpretation of magnetic and new gravity data provides constraints on the geometry of the Hat Creek Fault, the amount of right-lateral offset in the area between Mt. Shasta and Lassen Peak, and confirmation of the influence of pre-existing structure on Quaternary faulting. Neogene volcanic rocks coincide with short-wavelength magnetic anomalies of both normal and reversed polarity, whereas a markedly smoother magnetic field occurs over the Klamath Mountains and its Paleogene cover. Although the magnetic field over the Neogene volcanic rocks is complex, the Hat Creek Fault, which is one of the most prominent normal faults in the region and forms the eastern margin of the Hat Creek Valley, is marked by the eastern edge of a north-trending magnetic and gravity high 20-30 km long. Modeling of these anomalies indicates that the fault is a steeply dipping (~75-85°) structure. The spatial relationship of the fault as modeled by the potential-field data, the youngest strand of the fault, and relocated seismicity suggests that deformation continues to step westward across the valley, consistent with a component of right-lateral slip in an extensional environment. Filtered aeromagnetic data highlight a concealed magnetic body of Mesozoic or older age north of Hat Creek Valley. The body’s northwest margin strikes northeast and is linear over a distance of ~40 km. Within the resolution of the aeromagnetic data (1-2 km), we discern no right-lateral offset of this body. Furthermore, Quaternary faults change strike or appear to end, as if to avoid this concealed magnetic body and to pass along its southeast edge, suggesting that pre-existing crustal structure influenced younger faulting, as previously proposed based on gravity data.

Fault structure and kinematics of the Long Valley Caldera region, California, revealed by high-accuracy earthquake hypocenters and focal mechanism stress inversions

Science.gov (United States)

Prejean, Stephanie; Ellsworth, William L.; Zoback, Mark; Waldhauser, Felix

2002-01-01

We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west-striking right-lateral strike-slip faults beneath the caldera's south moat and a series of more northerly striking strike-slip/normal faults beneath the caldera's resurgent dome. Seismicity in the SNB south of the caldera is confined to a crustal block bounded on the west by an east-dipping oblique normal fault and on the east by the Hilton Creek fault. Two NE-striking left-lateral strike-slip faults are responsible for most seismicity within this block. To understand better the stresses driving seismicity, we performed stress inversions using focal mechanisms with 50 or more first motions. This analysis reveals that the least principal stress direction systematically rotates across the studied region, from NE to SW in the caldera's south moat to WNW-ESE in Round Valley, 25 km to the SE. Because WNW-ESE extension is characteristic of the western boundary of the Basin and Range province, caldera area stresses appear to be locally perturbed. This stress perturbation does not seem to result from magma chamber inflation but may be related to the significant (???20 km) left step in the locus of extension along the Sierra Nevada/Basin and Range province boundary. This implies that regional-scale tectonic processes are driving seismic deformation in the Long Valley caldera.

Scissoring Fault Rupture Properties along the Median Tectonic Line Fault Zone, Southwest Japan

Science.gov (United States)

Ikeda, M.; Nishizaka, N.; Onishi, K.; Sakamoto, J.; Takahashi, K.

2017-12-01

The Median Tectonic Line fault zone (hereinafter MTLFZ) is the longest and most active fault zone in Japan. The MTLFZ is a 400-km-long trench parallel right-lateral strike-slip fault accommodating lateral slip components of the Philippine Sea plate oblique subduction beneath the Eurasian plate [Fitch, 1972; Yeats, 1996]. Complex fault geometry evolves along the MTLFZ. The geomorphic and geological characteristics show a remarkable change through the MTLFZ. Extensional step-overs and pull-apart basins and a pop-up structure develop in western and eastern parts of the MTLFZ, respectively. It is like a "scissoring fault properties". We can point out two main factors to form scissoring fault properties along the MTLFZ. One is a regional stress condition, and another is a preexisting fault. The direction of σ1 anticlockwise rotate from N170°E [Famin et al., 2014] in the eastern Shikoku to Kinki areas and N100°E [Research Group for Crustral Stress in Western Japan, 1980] in central Shikoku to N85°E [Onishi et al., 2016] in western Shikoku. According to the rotation of principal stress directions, the western and eastern parts of the MTLFZ are to be a transtension and compression regime, respectively. The MTLFZ formed as a terrain boundary at Cretaceous, and has evolved with a long active history. The fault style has changed variously, such as left-lateral, thrust, normal and right-lateral. Under the structural condition of a preexisting fault being, the rupture does not completely conform to Anderson's theory for a newly formed fault, as the theory would require either purely dip-slip motion on the 45° dipping fault or strike-slip motion on a vertical fault. The fault rupture of the 2013 Barochistan earthquake in Pakistan is a rare example of large strike-slip reactivation on a relatively low angle dipping fault (thrust fault), though many strike-slip faults have vertical plane generally [Avouac et al., 2014]. In this presentation, we, firstly, show deep subsurface

The characteristics of the western extension of the Karakax fault in NW Tibet and its tectonic implications

Science.gov (United States)

Ge, C.; Liu, D.; Li, H.; Zheng, Y.; Pan, J.

2017-12-01

The Karakax strike-slip fault, located in northwest Tibet, is a mature deformation belt with a long-time evolutionary history, which is also active at present and plays an important role in the tectonic deformation of the northwestern Tibetan Plateau. Nowadays, most geologists consider that the Karakax fault is generally east-west striking along the Karakax river valley, and northwest striking until to the Tashkorgan in the Mazar area. However, an ENE-WSW fault was identified at the Mazar area, which sited at the bend of the Karakax fault, we named this fault as the Matar fault. Via the detailed geological survey, the similar geometry and kinematic characteristics were identified between the Karakax and Matar faults: (1) The similar fault zone scale(Karakax:90 300m; Matar:100 220m); (2) The similar preferred orientation (nearly EW) of the stretching lineations and foliations; (3) All the fault planes of the both faults have a high dip angle and is nearly EW striking; (4) Lots of ductile deformations, such as σ-type quartz rotational mortar, S-C fabric, symmetric drag fold and so on, indicated that the Matar fault is a right-lateral strike-slip and thrust fault during the early ductile deformation stage; (5) the deluvium, sheared by Matar fault, indicated that the Matar fault has already transformed into a left-lateral strike-slip fault during the later brittle deformation stage. All the above showed that the Matar fault has a similar geometry and kinematic characteristics with the Karakax fault, and the former is the probable the western extension of the latter. Moreover, the form of the Karakax-Matar fault may had an impact to the geomorphology of the west Kunlun-Pamir area, such as the strike of the moutains and faults. considering the age of west Kunlun mountains uplifting and Karakax fault activating, we regard that the Matar fault (the westward extension of Karakax fault) may contributes much in forming the modern geomorphology features of the west Kunlun

Bird/Wildlife Strike Control for Safer Air Transportation in Nigeria ...

African Journals Online (AJOL)

Kites and hawks were found to be responsible for 57% of reported strikes. Several factors including lack of adequate data, shortage of funds, inadequate training of staff and lack of public awareness about bird/wildlife hazard were found to be militating against effective control in Nigeria. The paper concludes by making ...

Bringing Cost-Wise Readiness to the Deckplates of a Strike Fighter Squadron Using the Balanced Scorecard

Science.gov (United States)

2013-12-01

Perspective Input Sheet ...................................................................97 Figure 26. Strike Fighter Balanced Scorecard Dashboard ...financial success (e.g., revenue growth, profit margin, cash flow) • Define the customer value proposition • Define processes that facilitate customer...Environment I 3 I I 3 I 1.00 3 3 Total Total 16.00 14.26 89% 98 Figure 26. Strike Fighter Balanced Scorecard Dashboard 99 LIST OF REFERENCES

Along strike variation of active fault arrays and their effect on landscape morphology of the northwestern Himalaya

Science.gov (United States)

Nennewitz, Markus; Thiede, Rasmus; Bookhagen, Bodo

2017-04-01

location of along strike changes which are interpreted as their segment boundaries. In addition to the steepness indices we use the accumulation of elevation data as a proxy for the strain that has been accumulated over a specific distance. Thus, despite the changes in topography, structural setting, and kinematics along the NW Himalaya we observe that the topography of the orogen is in good agreement with recently measured convergence rates obtained from GPS campaigns. These data suggest reduced crustal shortening towards the northwest. Deformation in the Central Himalaya has been explained either by in-sequence thrusting along the MFT that localize the entire Holocene shortening or a combination of this with out-of-sequence thrusting in the vicinity of the PT2. In contrast to these conceptual models, we propose that the segmented NW Himalaya is a product of the synchronous activity of different fault segments, accommodating the crustal shortening along three independently deforming organic segments. The lateral discontinuity of these segments is responsible for the accommodation of the variation in the deformation and the maintenance of the topography of the Himalaya in NW India.

Research on Line Patrol Strategy of 110kV Transmission Line after Lightning Strike

Directory of Open Access Journals (Sweden)

Li Mingjun

2016-01-01

Full Text Available Lightning faults occupy in the majority of instantaneous fault and reclosing can usually be successful, so power supply can be restored without immediate patrol in many cases. Firstly, this paper introduces the lightning fault positioning and identifying method. Then test electrical performance of insulators after lightning strike from 110kV lines. Data shows that lightning strike has little effect on the electric performance of insulator. Finally, illustrating disposal process of the 110 kV transmission line after lightning fault, certifying that the power supply reliability be ensured without line patrol.

Becoming stronger by becoming weaker: the hunger strike as a mode of doing politics

DEFF Research Database (Denmark)

Abrahamsson, Carl Sebastian; Danyi, Endre

2018-01-01

immigrants, we aim to achieve three things. First, we foreground physical bodies as political entities caught up in multiple modes of doing politics. Second, we show how such modes relate to one another, reinforcing citizenship, activism and party politics as specific performances of agency associated...... with liberal democracy. Finally, we argue that the Brussels hunger strike also challenges these performances by failing to meet certain expectations about what it is to be political/act politically. As the European refugee crisis is generating louder and louder voices, hunger strikes sensitise us to modes...

Deformed Fluvial Terraces of Little Rock Creek Capture Off-Fault Strain Adjacent to the Mojave Section of the San Andreas Fault

Science.gov (United States)

Moulin, A.; Scharer, K. M.; Cowgill, E.

2017-12-01

Examining discrepancies between geodetic and geomorphic slip-rates along major strike-slip faults is essential for understanding both fault behavior and seismic hazard. Recent work on major strike-slip faults has highlighted off-fault deformation and its potential impact on fault slip rates. However, the extent of off-fault deformation along the San Andreas Fault (SAF) remains largely uncharacterized. Along the Mojave section of the SAF, Little Rock Creek drains from south to north across the fault and has cut into alluvial terraces abandoned between 15 and 30 ka1. The surfaces offer a rare opportunity to both characterize how right-lateral slip has accumulated along the SAF over hundreds of seismic cycles, and investigate potential off-fault deformation along secondary structures, where strain accumulates at slower rates. Here we use both field observations and DEM analysis of B4 lidar data to map alluvial and tectonic features, including 9 terrace treads that stand up to 80 m above the modern channel. We interpret the abandonment and preservation of the fluvial terraces to result from episodic capture of Little Rock Creek through gaps in a shutter ridge north of the fault, followed by progressive right deflection of the river course during dextral slip along the SAF. Piercing lines defined by fluvial terrace risers suggest that the amount of right slip since riser formation ranges from 400m for the 15-ka-riser to 1200m for the 30-ka-riser. Where they are best-preserved NE of the SAF, terraces are also cut by NE-facing scarps that trend parallel to the SAF in a zone extending up to 2km from the main fault. Exposures indicate these are fault scarps, with both reverse and normal stratigraphic separation. Geomorphic mapping reveals deflections of both channel and terrace risers (up to 20m) along some of those faults suggesting they could have accommodated a component of right-lateral slip. We estimated the maximum total amount of strike-slip motion recorded by the

Exploiting Science: Enhancing the Safety Training of Pilots to Reduce the Risk of Bird Strikes

Science.gov (United States)

Mendonca, Flavio A. C.

Analysis of bird strikes to aviation in the U.S. from 1990 to 2015 indicate that the successful mitigation efforts at airports, which must be sustained, have reduced incidents with damage and a negative effect-on-flight since 2000. However, such efforts have done little to reduce strikes outside the airport jurisdiction, such as occurred with US Airways Flight 1549 in 2009. There are basically three strategies to mitigate the risk of bird strikes: standards set by aviation authorities, technology, and actions by crewmembers. Pilots play an important role as stakeholders in the prevention of bird strikes, especially outside the airport environment. Thus, safety efforts require enhanced risk management and aeronautical decision-making training for flight crews. The purpose of this study was to determine if a safety training protocol could effectively enhance CFR Part 141 general aviation pilots' knowledge and skills to reduce the risk of bird strikes to aviation. Participants were recruited from the Purdue University professional flight program and from Purdue Aviation. The researcher of this study used a pretest posttest experimental design. Additionally, qualitative data were collected through open-ended questions in the pretest, posttest, and a follow-up survey questionnaire. The participants' pretest and posttest scores were analyzed using parametric and nonparametric tests. Results indicated a significant increase in the posttest scores of the experimental group. An investigation of qualitative data showed that the topic "safety management of bird hazards by pilots" is barely covered during the ground and flight training of pilots. Furthermore, qualitative data suggest a misperception of the safety culture tenets and a poor familiarity with the safety risk management process regarding bird hazards. Finally, the researcher presented recommendations for practice and future research.

The effects of industrial conflicts and strikes in Nigeria: A socio ...

African Journals Online (AJOL)

This paper further averred that while industrial conflicts, strikes and work stoppages affect tremendously the economic development of Nigeria through low national productivity, it also has serious sociological consequences such as the dislocation and severance of the socialisation function of work. The paper therefore ...

Analysis of the effects of frequent strikes on academic performance ...

African Journals Online (AJOL)

The history of Academic Staff Union of Universities (ASUU)'s strike can be traced back to 1978, the period of the beginning of the decline in the oil boom, when the country faced the consequences of the failure by its rulers to use the oil wealth to generate production and a social welfare system. Military dictatorship had ...

Impact of Job Satisfaction and Burnout on Attitudes towards Strike Action among Employees of a Nigerian University

Science.gov (United States)

Ineme, Kubiat M.; Ineme, Mfon E.

2016-01-01

The Nigerian tertiary educational system has been ravaged by incessant strike action, which appears to defy all attempts to find solutions. This paper reports on a study that examines the impact of job satisfaction and burnout on attitudes towards strike actions among employees of a Nigerian university. A total of 576 employees participated in the…

Synthesis and testing of a conducting polymeric composite material for lightning strike protection applications

Science.gov (United States)

Katunin, A.; Krukiewicz, K.; Turczyn, R.; Sul, P.; Łasica, A.; Catalanotti, G.; Bilewicz, M.

2017-02-01

Lightning strike protection is one of the important issues in the modern maintenance problems of aircraft. This is due to a fact that the most of exterior elements of modern aircraft is manufactured from polymeric composites which are characterized by isolating electrical properties, and thus cannot carry the giant electrical charge when the lightning strikes. This causes serious damage of an aircraft structure and necessity of repairs and tests before returning a vehicle to operation. In order to overcome this problem, usually metallic meshes are immersed in the polymeric elements. This approach is quite effective, but increases a mass of an aircraft and significantly complicates the manufacturing process. The approach proposed by the authors is based on a mixture of conducting and dielectric polymers. Numerous modeling studies which are based on percolation clustering using kinetic Monte Carlo methods, finite element modeling of electrical and mechanical properties, and preliminary experimental studies, allow achieving an optimal content of conducting particles in a dielectric matrix in order to achieve possibly the best electrical conductivity and mechanical properties, simultaneously. After manufacturing the samples with optimal content of a conducting polymer, mechanical and electrical characterization as well as high-voltage testing was performed. The application of such a material simplifies manufacturing process and ensures unique properties of aircraft structures, which allows for minimizing damage after lightning strike, as well as provide electrical bounding and grounding, interference shielding, etc. The proposed solution can minimize costs of repair, testing and certification of aircraft structures damaged by lightning strikes.

Simulating Bird Strike on Aircraft Composite Wing Leading Edge.

OpenAIRE

Ericsson, Max

2012-01-01

In this master thesis project the possibility to model the response of a wing when subjected to bird strike using finite elements is analyzed. Since this transient event lasts only a few milliseconds the used solution method is explicit time integration. The wing is manufactured using carbon fiber laminate. Carbon fiber laminates have orthotropic material properties with different stiffness in different directions. Accordingly, there are damage mechanisms not considered when using metal that ...

Actual and perceived collision risk for bird strikes at Namibian airports

African Journals Online (AJOL)

At Namibia's two major airports, Hosea Kutako International and Eros (domestic), 117 bird strike collision incidents were recorded between 2006 and 2010. A risk assessment, which included a proposed risk weighting methodology, was conducted at Hosea Kutako and Eros airports, which estimated the probability of an ...

Combat Pair: The Evolution of Air Force-Navy Integration in Strike Warfare

National Research Council Canada - National Science Library

Lambeth, Benjamin

2007-01-01

This report documents the exceptional cross-service harmony that the U.S. Air Force and U.S. Navy have steadily developed in their conduct of integrated strike operations since the first Persian Gulf War in 1991...

Surface slip during large Owens Valley earthquakes

KAUST Repository

Haddon, E. K.; Amos, C. B.; Zielke, Olaf; Jayko, A. S.; Burgmann, R.

2016-01-01

The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross-correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) for each measurement. Stacking PDFs along strike to form cumulative offset probability distribution plots (COPDs) highlights common values corresponding to single and multiple-event displacements. Lateral offsets for 1872 vary systematically from approximate to 1.0 to 6.0 m and average 3.31.1 m (2 sigma). Vertical offsets are predominantly east-down between approximate to 0.1 and 2.4 m, with a mean of 0.80.5 m. The average lateral-to-vertical ratio compiled at specific sites is approximate to 6:1. Summing displacements across subparallel, overlapping rupture traces implies a maximum of 7-11 m and net average of 4.41.5 m, corresponding to a geologic M-w approximate to 7.5 for the 1872 event. We attribute progressively higher-offset lateral COPD peaks at 7.12.0 m, 12.8 +/- 1.5 m, and 16.6 +/- 1.4 m to three earlier large surface ruptures. Evaluating cumulative displacements in context with previously dated landforms in Owens Valley suggests relatively modest rates of fault slip, averaging between approximate to 0.6 and 1.6 mm/yr (1 sigma) over the late Quaternary.

Surface slip during large Owens Valley earthquakes

Science.gov (United States)

Haddon, E.K.; Amos, C.B.; Zielke, O.; Jayko, Angela S.; Burgmann, R.

2016-01-01

The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross-correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) for each measurement. Stacking PDFs along strike to form cumulative offset probability distribution plots (COPDs) highlights common values corresponding to single and multiple-event displacements. Lateral offsets for 1872 vary systematically from ∼1.0 to 6.0 m and average 3.3 ± 1.1 m (2σ). Vertical offsets are predominantly east-down between ∼0.1 and 2.4 m, with a mean of 0.8 ± 0.5 m. The average lateral-to-vertical ratio compiled at specific sites is ∼6:1. Summing displacements across subparallel, overlapping rupture traces implies a maximum of 7–11 m and net average of 4.4 ± 1.5 m, corresponding to a geologic Mw ∼7.5 for the 1872 event. We attribute progressively higher-offset lateral COPD peaks at 7.1 ± 2.0 m, 12.8 ± 1.5 m, and 16.6 ± 1.4 m to three earlier large surface ruptures. Evaluating cumulative displacements in context with previously dated landforms in Owens Valley suggests relatively modest rates of fault slip, averaging between ∼0.6 and 1.6 mm/yr (1σ) over the late Quaternary.

Surface slip during large Owens Valley earthquakes

KAUST Repository

Haddon, E. K.

2016-01-10

The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross-correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) for each measurement. Stacking PDFs along strike to form cumulative offset probability distribution plots (COPDs) highlights common values corresponding to single and multiple-event displacements. Lateral offsets for 1872 vary systematically from approximate to 1.0 to 6.0 m and average 3.31.1 m (2 sigma). Vertical offsets are predominantly east-down between approximate to 0.1 and 2.4 m, with a mean of 0.80.5 m. The average lateral-to-vertical ratio compiled at specific sites is approximate to 6:1. Summing displacements across subparallel, overlapping rupture traces implies a maximum of 7-11 m and net average of 4.41.5 m, corresponding to a geologic M-w approximate to 7.5 for the 1872 event. We attribute progressively higher-offset lateral COPD peaks at 7.12.0 m, 12.8 +/- 1.5 m, and 16.6 +/- 1.4 m to three earlier large surface ruptures. Evaluating cumulative displacements in context with previously dated landforms in Owens Valley suggests relatively modest rates of fault slip, averaging between approximate to 0.6 and 1.6 mm/yr (1 sigma) over the late Quaternary.

Bird-strike of a Cinereous Vulture Aegypius monachus in the ...

African Journals Online (AJOL)

Campbell Murn

Bird-strike of a Cinereous Vulture Aegypius monachus in the Balearic Islands, Spain. Alvaro Camiña1* and Joan ... http://dx.doi.org/10.4314/vulnew.v71i1.3. On 15 September 2016 a Lufthansa flight en route from Munich ... nautical miles from runway 24L. Considering the altitude of the area of around 100 meters, the bird ...

Foot strike pattern differently affects the axial and transverse components of shock acceleration and attenuation in downhill trail running.

Science.gov (United States)

Giandolini, Marlene; Horvais, Nicolas; Rossi, Jérémy; Millet, Guillaume Y; Samozino, Pierre; Morin, Jean-Benoît

2016-06-14

Trail runners are exposed to a high number of shocks, including high-intensity shocks on downhill sections leading to greater risk of osseous overuse injury. The type of foot strike pattern (FSP) is known to influence impact severity and lower-limb kinematics. Our purpose was to investigate the influence of FSP on axial and transverse components of shock acceleration and attenuation during an intense downhill trail run (DTR). Twenty-three trail runners performed a 6.5-km DTR (1264m of negative elevation change) as fast as possible. Four tri-axial accelerometers were attached to the heel, metatarsals, tibia and sacrum. Accelerations were continuously recorded at 1344Hz and analyzed over six sections (~400 steps per subject). Heel and metatarsal accelerations were used to identify the FSP. Axial, transverse and resultant peak accelerations, median frequencies and shock attenuation within the impact-related frequency range (12-20Hz) were assessed between tibia and sacrum. Multiple linear regressions showed that anterior (i.e. forefoot) FSPs were associated with higher peak axial acceleration and median frequency at the tibia, lower transverse median frequencies at the tibia and sacrum, and lower transverse peak acceleration at the sacrum. For resultant acceleration, higher tibial median frequency but lower sacral peak acceleration were reported with forefoot striking. FSP therefore differently affects the components of impact shock acceleration. Although a forefoot strike reduces impact severity and impact frequency content along the transverse axis, a rearfoot strike decreases them in the axial direction. Globally, the attenuation of axial and resultant impact-related vibrations was improved using anterior FSPs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Incipient Evolution of the Eastern California Shear Zone through a Transpressional Zone along the San Andreas Fault in the San Bernardino Mountains, California

Science.gov (United States)

Cochran, W. J.; Spotila, J. A.

2017-12-01

Measuring long-term accumulation of strike-slip displacements and transpressional uplift is difficult where strain is accommodated across wide shear zones, as opposed to a single major fault. The Eastern California Shear Zone (ECSZ) in southern California accommodates dextral shear across several strike-slip faults, and is potentially migrating and cutting through a formerly convergent zone of the San Bernardino Mountains (SBM). The advection of crust along the San Andreas fault to the SE has forced these two tectonic regimes into creating a nexus of interacting strike-slip faults north of San Gorgonio Pass. These elements make this region ideal for studying complex fault interactions, evolving fault geometries, and deformational overprinting within a wide shear zone. Using high-resolution topography and field mapping, this study aims to test whether diffuse, poorly formed strike-slip faults within the uplifted SBM block are nascent elements of the ECSZ. Topographic resolution of ≤ 1m was achieved using both lidar and UAV surveys along two Quaternary strike-slip faults, namely the Lake Peak fault and Lone Valley faults. Although the Lone Valley fault cuts across Quaternary alluvium, the geomorphic expression is obscured, and may be the result of slow slip rates. In contrast, the Lake Peak fault is located high elevations north of San Gorgonio Peak in the SBM, and displaces Quaternary glacial deposits. The deposition of large boulders along the escarpment also obscures the apparent magnitude of slip along the fault. Although determining fault offset is difficult, the Lake Peak fault does display evidence for minor right-lateral displacement, where the magnitude of slip would be consistent with individual faults within the ECSZ (i.e. ≤ 1 mm/yr). Compared to the preservation of displacement along strike-slip faults located within the Mojave Desert, the upland region of the SBM adds complexity for measuring fault offset. The distribution of strain across the entire

A novel anisotropic inversion approach for magnetotelluric data from subsurfaces with orthogonal geoelectric strike directions

Science.gov (United States)

Schmoldt, Jan-Philipp; Jones, Alan G.

2013-12-01

The key result of this study is the development of a novel inversion approach for cases of orthogonal, or close to orthogonal, geoelectric strike directions at different depth ranges, for example, crustal and mantle depths. Oblique geoelectric strike directions are a well-known issue in commonly employed isotropic 2-D inversion of MT data. Whereas recovery of upper (crustal) structures can, in most cases, be achieved in a straightforward manner, deriving lower (mantle) structures is more challenging with isotropic 2-D inversion in the case of an overlying region (crust) with different geoelectric strike direction. Thus, investigators may resort to computationally expensive and more limited 3-D inversion in order to derive the electric resistivity distribution at mantle depths. In the novel approaches presented in this paper, electric anisotropy is used to image 2-D structures in one depth range, whereas the other region is modelled with an isotropic 1-D or 2-D approach, as a result significantly reducing computational costs of the inversion in comparison with 3-D inversion. The 1- and 2-D versions of the novel approach were tested using a synthetic 3-D subsurface model with orthogonal strike directions at crust and mantle depths and their performance was compared to results of isotropic 2-D inversion. Structures at crustal depths were reasonably well recovered by all inversion approaches, whereas recovery of mantle structures varied significantly between the different approaches. Isotropic 2-D inversion models, despite decomposition of the electric impedance tensor and using a wide range of inversion parameters, exhibited severe artefacts thereby confirming the requirement of either an enhanced or a higher dimensionality inversion approach. With the anisotropic 1-D inversion approach, mantle structures of the synthetic model were recovered reasonably well with anisotropy values parallel to the mantle strike direction (in this study anisotropy was assigned to the

Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics

Directory of Open Access Journals (Sweden)

Kevin A. Valenzuela, Scott K. Lynn, Lisa R. Mikelson, Guillermo J. Noffal, Daniel A. Judelson

2015-03-01

Full Text Available subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m. On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern –forefoot strike [FFS], rearfoot strike [RFS] x 2 (Group – PFFG, PRFG mixed model ANOVAs (p < 0.05 were run on speed, active peak vertical ground reaction force (VGRF, peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW, dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg-1, FFS = -3.09 ± 0.32 Nm·kg-1, and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°. There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg-1, FFS = 0.01 ± 0.01 Nm·kg-1, peak knee moment (RFS = 2.61 ± 0.54 Nm·kg-1, FFS = 2.39 ± 0.61 Nm·kg-1, knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°, and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32° as compared with the FFS condition. This research suggests that acute changes in foot strike patterns during shod running can create alterations in certain lower limb kinematic and kinetic measures that are not dependent on the preferred foot strike pattern of the individual. This research also challenges the contention that the impact transient spike in the vertical ground reaction force curve is only present during a rear foot strike type of running gait.

Pseudodynamic Source Characterization for Strike-Slip Faulting Including Stress Heterogeneity and Super-Shear Ruptures

KAUST Repository

Mena, B.; Dalguer, L. A.; Mai, Paul Martin

2012-01-01

. (2004), we propose new relationships for PD models for moderate‐to‐large strike‐slip earthquakes that include local supershear rupture speed due to stress heterogeneities. We conduct dynamic rupture simulations using stochastic initial stress

PSpice Model of Lightning Strike to a Steel Reinforced Structure

International Nuclear Information System (INIS)

Koone, Neil; Condren, Brian

2003-01-01

Surges and arcs from lightning can pose hazards to personnel and sensitive equipment, and processes. Steel reinforcement in structures can act as a Faraday cage mitigating lightning effects. Knowing a structure's response to a lightning strike allows hazards associated with lightning to be analyzed. A model of lightning's response in a steel reinforced structure has been developed using PSpice (a commercial circuit simulation). Segments of rebar are modeled as inductors and resistors in series. A program has been written to take architectural information of a steel reinforced structure and 'build' a circuit network that is analogous to the network of reinforcement in a facility. A severe current waveform (simulating a 99th percentile lightning strike), modeled as a current source, is introduced in the circuit network, and potential differences within the structure are determined using PSpice. A visual three-dimensional model of the facility displays the voltage distribution across the structure using color to indicate the potential difference relative to the floor. Clear air arcing distances can be calculated from the voltage distribution using a conservative value for the dielectric breakdown strength of air. Potential validation tests for the model will be presented

Cardiac Arrest Secondary to Lightning Strike: Case Report and Review of the Literature.

Science.gov (United States)

Rotariu, Elena L; Manole, Mioara D

2017-08-01

Lightning strike injuries, although less common than electrical injuries, have a higher morbidity rate because of critical alterations of the circulatory system, respiratory system, and central nervous system. Most lightning-related deaths occur immediately after injury because of arrhythmia or respiratory failure. We describe the case of a pediatric patient who experienced cardiorespiratory arrest secondary to a lightning strike, where the Advanced Cardiac Life Support and Basic Life Support chain of survival was well executed, leading to return of spontaneous circulation and intact neurological survival. We review the pathophysiology of lightning injuries, prognostic factors of favorable outcome after cardiac arrest, including bystander cardiopulmonary resuscitation, shockable rhythm, and automatic external defibrillator use, and the importance of temperature management after cardiac arrest.

Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues

Science.gov (United States)

2016-02-24

FY2008, Congress rejected the requested funding for this program, but the Navy has continued to consider the possibility of deploying intermediate ...10 Submarine-Launched Intermediate -Range Global Strike .................................................. 11 Air Force Programs...Missiles............................................................................ 36 Submarine-Launched Intermediate -Range Ballistic Missiles

Annotated Bibliography of Bird Hazards to Aircraft: Bird Strike Committee Citations 1967-1997

National Research Council Canada - National Science Library

Short, Jeffrey

1998-01-01

.... This annotated bibliography of bird hazards to aircraft, termed ABBHA, is a compilation of citations with abstracts on a wide range of related topics such as bird strike tolerance engineering, bird...

Agreement reached at Unilever after three-week strike over plant closures

NARCIS (Netherlands)

Grünell, M.

2008-01-01

In mid October 2007, staff at the Unilever plant in the Netherlands went on strike for over three weeks in protest against the group’s plan to close three of the country’s six Unilever plants. The trade unions believe that the closures are unnecessary and are calling for job guarantees for employees

Evidence of a double peak in muscle activation to enhance strike speed and force: an example with elite mixed martial arts fighters.

Science.gov (United States)

McGill, Stuart M; Chaimberg, Jon D; Frost, David M; Fenwick, Chad M J

2010-02-01

The main issue addressed here is the paradox of muscle contraction to optimize speed and strike force. When muscle contracts, it increases in both force and stiffness. Force creates faster movement, but the corresponding stiffness slows the change of muscle shape and joint velocity. The purpose of this study was to investigate how this speed strength is accomplished. Five elite mixed martial arts athletes were recruited given that they must create high strike force very quickly. Muscle activation using electromyography and 3-dimensional spine motion was measured. A variety of strikes were performed. Many of the strikes intend to create fast motion and finish with a very large striking force, demonstrating a "double peak" of muscle activity. An initial peak was timed with the initiation of motion presumably to enhance stiffness and stability through the body before motion. This appeared to create an inertial mass in the large "core" for limb muscles to "pry" against to initiate limb motion. Then, some muscles underwent a relaxation phase as speed of limb motion increased. A second peak was observed upon contact with the opponent (heavy bag). It was postulated that this would increase stiffness through the body linkage, resulting in a higher effective mass behind the strike and likely a higher strike force. Observation of the contract-relax-contract pulsing cycle during forceful and quick strikes suggests that it may be fruitful to consider pulse training that involves not only the rate of muscle contraction but also the rate of muscle relaxation.

Principles Governing the Mechanics and Control of Snake Strikes

Science.gov (United States)

2015-06-26

small, potentially evasive target with an impact sufficient for prey capture but without 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13...strike a small, potentially evasive target with an impact sufficient for prey capture but without damaging their lightly-built skull. Although the...p o rt io n o f To ta l M as s Segment Number Boa/Python Mean Colubrid Mean Viper Mean Figure 3 – Proportion of body mass in each of 10 equal-length

Estimation of the Risks of Collision or Strike to Freshwater Aquatic Organisms Resulting from Operation of Instream Hydrokinetic Turbines

Energy Technology Data Exchange (ETDEWEB)

Schweizer, Peter E [ORNL; Cada, Glenn F [ORNL; Bevelhimer, Mark S [ORNL

2010-05-01

Hydrokinetic energy technologies have been proposed as renewable, environmentally preferable alternatives to fossil fuels for generation of electricity. Hydrokinetic technologies harness the energy of water in motion, either from waves, tides or from river currents. For energy capture from free-flowing rivers, arrays of rotating devices are most commonly proposed. The placement of hydrokinetic devices in large rivers is expected to increase the underwater structural complexity of river landscapes. Moore and Gregory (1988) found that structural complexity increased local fish populations because fish and other aquatic biota are attracted to structural complexity that provides microhabitats with steep flow velocity gradients (Liao 2007). However, hydrokinetic devices have mechanical parts, blades, wings or bars that move through the water column, posing a potential strike or collision risk to fish and other aquatic biota. Furthermore, in a setting with arrays of hydrokinetic turbines the cumulative effects of multiple encounters may increase the risk of strike. Submerged structures associated with a hydrokinetic (HK) project present a collision risk to aquatic organisms and diving birds (Cada et al. 2007). Collision is physical contact between a device or its pressure field and an organism that may result in an injury to that organism (Wilson et al. 2007). Collisions can occur between animals and fixed submerged structures, mooring equipment, horizontal or vertical axis turbine rotors, and structures that, by their individual design or in combination, may form traps. This report defines strike as a special case of collision where a moving part, such as a rotor blade of a HK turbine intercepts the path of an organism of interest, resulting in physical contact with the organism. The severity of a strike incidence may range from minor physical contact with no adverse effects to the organism to severe strike resulting in injury or death of the organism. Harmful effects

Geometry and Kinematics of the Lopukangri Fault System: Implications for Internal Deformation of the Tibetan Plateau

Science.gov (United States)

Murphy, M. A.; Taylor, M. H.

2006-12-01

We present geologic mapping and structural data from the Lopukangri fault system in south-central Tibet that sheds light on the geometry, kinematics and spatial characteristics of deformation in western Tibet and the western Himalaya. The Lopukangri fault system strikes N09E and extends 150 km from the Lhasa terrane into the Tethyan fold-thrust belt at 84.5° N. Geologic mapping shows that the deformation is accommodated by a northwest dipping oblique fault system, which accommodates both right-lateral and normal dip-slip movement, consistent with right-lateral separations of Quaternary surficial deposits. The fault system juxtaposes amphibolite-grade rocks in its footwall against greenschist-grade rocks in its hanging wall. Deformation is distributed over a 4 km wide zone that predominately records right-lateral normal slip in ductile and brittle shear fabrics. The fault system right-laterally separates the Gangdese batholith, Kailas conglomerate, Great Counter thrust, and the Tethyan fold-thrust belt for 15 km. Age estimates of the Kailas conglomerate in the Kailas region implies that the Lopukangri fault system initiated after the Early Miocene( 23Ma). The observation that the Lopukangri fault system cuts the Indus-Yaly suture zone, rules out active strike-slip faulting along it at this locality. To assess the role of the Lopukangri fault system in accommodating strain within western Tibet, we compare our results with fault-slip data and structural geometries from the Karakoram and Dangardzong (Thakkhola graben) fault systems. The Dangardzong fault shares similar kinematics with the Lopukangri fault system, both display a significant component of right-slip. Although the two faults do not strike into one another, they may be linked via a transfer zone. The Karakoram fault accommodates right-lateral slip in which a portion of the total slip extends from the Tibetan plateau into the Himalayan thrust belt via right-stepover structures. Fault slip data from the

Effects of track and threat information on judgments of hurricane strike probability.

Science.gov (United States)

Wu, Hao-Che; Lindell, Michael K; Prater, Carla S; Samuelson, Charles D

2014-06-01

Although evacuation is one of the best strategies for protecting citizens from hurricane threat, the ways that local elected officials use hurricane data in deciding whether to issue hurricane evacuation orders is not well understood. To begin to address this problem, we examined the effects of hurricane track and intensity information in a laboratory setting where participants judged the probability that hypothetical hurricanes with a constant bearing (i.e., straight line forecast track) would make landfall in each of eight 45 degree sectors around the Gulf of Mexico. The results from 162 participants in a student sample showed that the judged strike probability distributions over the eight sectors within each scenario were, unsurprisingly, unimodal and centered on the sector toward which the forecast track pointed. More significantly, although strike probability judgments for the sector in the direction of the forecast track were generally higher than the corresponding judgments for the other sectors, the latter were not zero. Most significantly, there were no appreciable differences in the patterns of strike probability judgments for hurricane tracks represented by a forecast track only, an uncertainty cone only, or forecast track with an uncertainty cone-a result consistent with a recent survey of coastal residents threatened by Hurricane Charley. The study results suggest that people are able to correctly process basic information about hurricane tracks but they do make some errors. More research is needed to understand the sources of these errors and to identify better methods of displaying uncertainty about hurricane parameters. © 2013 Society for Risk Analysis.

The effect of core training on distal limb performance during ballistic strike manoeuvres.

Science.gov (United States)

Lee, Benjamin; McGill, Stuart

2017-09-01

Ballistic limb motion is enabled by proximal "core" stiffness. However, controversy exists regarding the best method of training this characteristic. This study sought to determine the most effective core training method to enhance distal limb athleticism. A total of 12 participants (24 ± 3 years, 1.8 ± 0.05 m, 76.8 ± 9.7 kg) consisting of Muay Thai athletes performed a core training protocol (Isometric vs. Dynamic, with Control) for 6 weeks, using a repeated measures design to assess performance (peak strike velocity, peak impact force, muscular activation) in various strikes. Isometric training increased impact force in Jab (554.4 ± 70.1 N), Cross (1895.2 ± 203.1 N), Combo (616.8 ± 54.9 N), and Knee (1240.0 ± 89.1 N) trials (P training increased strike velocity in Jab (1.3 ± 0.2 m · s -1 ), Cross (5.5 ± 0.9 m · s -1 ), Combo (0.7 ± 0.1, 2.8 ± 0.3 m · s -1 ), and Knee (3.2 ± 0.3 m · s -1 ) trials (P training increased Combo impact force 935.1 ± 100.3 N greater than Dynamic and 931.6 ± 108.5 N more than Control (P training increased Jab strike velocity 1.3 ± 0.1 m · s -1 greater than Isometric and 0.8 ± 0.1 m · s -1 more than Control (P core training are needed to enhance both velocity and force in distal limbs.

F-35 Joint Strike Fighter: Preliminary Observations on Program Progress

Science.gov (United States)

2016-03-23

current fighter aircraft. The cost of extending the lives of current fighter aircraft and acquiring other major weapon systems, while continuing to... Norway . Ongoing Manufacturing and Reliability Progress Continue Page 12 GAO-16-489T rework, and repair costs have remained steady over...Program Progress Why GAO Did This Study With estimated acquisition costs of nearly $400 billion, the F-35 Joint Strike Fighter—also known as the

Concept of a Conducting Composite Material for Lightning Strike Protection

OpenAIRE

Katunin A.; Krukiewicz K.; Herega A.; Catalanotti G.

2016-01-01

The paper focuses on development of a multifunctional material which allows conducting of electrical current and simultaneously holds mechanical properties of a polymeric composite. Such material could be applied for exterior fuselage elements of an aircraft in order to minimize damage occurring during lightning strikes. The concept introduced in this paper is presented from the points of view of various scientific disciplines including materials science, chemistry, structural physics and mec...

Seismic attribute detection of faults and fluid pathways within an active strike-slip shear zone: New insights from high-resolution 3D P-Cable™ seismic data along the Hosgri Fault, offshore California

Science.gov (United States)

Kluesner, Jared W.; Brothers, Daniel

2016-01-01

Poststack data conditioning and neural-network seismic attribute workflows are used to detect and visualize faulting and fluid migration pathways within a 13.7 km2 13.7 km2 3D P-Cable™ seismic volume located along the Hosgri Fault Zone offshore central California. The high-resolution 3D volume used in this study was collected in 2012 as part of Pacific Gas and Electric’s Central California Seismic Imaging Project. Three-dimensional seismic reflection data were acquired using a triple-plate boomer source (1.75 kJ) and a short-offset, 14-streamer, P-Cable system. The high-resolution seismic data were processed into a prestack time-migrated 3D volume and publically released in 2014. Postprocessing, we employed dip-steering (dip and azimuth) and structural filtering to enhance laterally continuous events and remove random noise and acquisition artifacts. In addition, the structural filtering was used to enhance laterally continuous edges, such as faults. Following data conditioning, neural-network based meta-attribute workflows were used to detect and visualize faults and probable fluid-migration pathways within the 3D seismic volume. The workflow used in this study clearly illustrates the utility of advanced attribute analysis applied to high-resolution 3D P-Cable data. For example, results from the fault attribute workflow reveal a network of splayed and convergent fault strands within an approximately 1.3 km wide shear zone that is characterized by distinctive sections of transpressional and transtensional dominance. Neural-network chimney attribute calculations indicate that fluids are concentrated along discrete faults in the transtensional zones, but appear to be more broadly distributed amongst fault bounded anticlines and structurally controlled traps in the transpressional zones. These results provide high-resolution, 3D constraints on the relationships between strike-slip fault mechanics, substrate deformation, and fluid migration along an active

First negative ion beam measurement by the Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE)

Science.gov (United States)

Serianni, G.; De Muri, M.; Muraro, A.; Veltri, P.; Bonomo, F.; Chitarin, G.; Pasqualotto, R.; Pavei, M.; Rizzolo, A.; Valente, M.; Franzen, P.; Ruf, B.; Schiesko, L.

2014-02-01

The Source for Production of Ion of Deuterium Extracted from Rf plasma (SPIDER) test facility is under construction in Padova to optimise the operation of the beam source of ITER neutral beam injectors. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon-fibre-carbon-composite tiles. A small-scale version of the entire system has been employed in the BAvarian Test MAchine for Negative ions (BATMAN) testbed by arranging two prototype tiles in the vertical direction. The paper presents a description of the mini-STRIKE system and of the data analysis procedures, as well as some results concerning the BATMAN beam under varying operating conditions.

First negative ion beam measurement by the Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE)

International Nuclear Information System (INIS)

Serianni, G.; De Muri, M.; Veltri, P.; Bonomo, F.; Chitarin, G.; Pasqualotto, R.; Pavei, M.; Rizzolo, A.; Valente, M.; Muraro, A.; Franzen, P.; Ruf, B.; Schiesko, L.

2014-01-01

The Source for Production of Ion of Deuterium Extracted from Rf plasma (SPIDER) test facility is under construction in Padova to optimise the operation of the beam source of ITER neutral beam injectors. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon-fibre-carbon-composite tiles. A small-scale version of the entire system has been employed in the BAvarian Test MAchine for Negative ions (BATMAN) testbed by arranging two prototype tiles in the vertical direction. The paper presents a description of the mini-STRIKE system and of the data analysis procedures, as well as some results concerning the BATMAN beam under varying operating conditions

First negative ion beam measurement by the Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE)

Energy Technology Data Exchange (ETDEWEB)

Serianni, G., E-mail: gianluigi.serianni@igi.cnr.it; De Muri, M.; Veltri, P.; Bonomo, F.; Chitarin, G.; Pasqualotto, R.; Pavei, M.; Rizzolo, A.; Valente, M. [Consorzio RFX, Euratom-ENEA association, Corso Stati Uniti 4, 35127 Padova (Italy); Muraro, A. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy); Franzen, P.; Ruf, B.; Schiesko, L. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching bei München (Germany)

2014-02-15

The Source for Production of Ion of Deuterium Extracted from Rf plasma (SPIDER) test facility is under construction in Padova to optimise the operation of the beam source of ITER neutral beam injectors. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon-fibre-carbon-composite tiles. A small-scale version of the entire system has been employed in the BAvarian Test MAchine for Negative ions (BATMAN) testbed by arranging two prototype tiles in the vertical direction. The paper presents a description of the mini-STRIKE system and of the data analysis procedures, as well as some results concerning the BATMAN beam under varying operating conditions.

A rare manifestation of burns after lightning strike in rural Ghana: a case report.

Science.gov (United States)

Apanga, Paschal Awingura; Azumah, John Atigiba; Yiranbon, Joseph Bayewala

2017-07-25

Lightning is a natural phenomenon that mostly affects countries in the tropical and subtropical regions of the globe, including Ghana. Lightning strikes pose a global public health issue. Although strikes to humans are uncommon, it is associated with high morbidity and mortality. We present a case of a 10-year-old Ghanaian girl who got second-degree burns after being struck by lightning. She was put on an intravenous broad-spectrum antibiotic (ceftriaxone), Ringer's lactate, and her burns were dressed with sterile gauze impregnated with Vaseline (petroleum jelly) and silver sulfadiazine ointment. There was marked improvement on the 16 th day of treatment despite the lack in capacity of the hospital to carry out some laboratory diagnostic tests. On the 21 st day of treatment, the burns were completely healed without scars and contractures. This is evidence of burns due to lightning strike, despite its rare occurrence. This report will help inform those in doubt, particularly in communities where lightning injuries are associated with widespread superstition. The case report also revealed how rural healthcare can be challenging amid a lack of basic diagnostic equipment and logistics. However, in resource-limited settings, Vaseline (petroleum jelly) and silver sulfadiazine could be used in the treatment of burns.

Induction and Conduction Electromagnetic Waves Caused by Lightning Strike on the Low Voltage Network

Directory of Open Access Journals (Sweden)

Reynaldo Zoro

2010-10-01

Full Text Available Direct and indirect lightning strikes can disturb and induce low voltage overheadlines and it can produced overvoltage due to traveling waves along the lines. This overvoltage can damage the equipments connected to it. It was recorded that there were already a lot of damages of electronic equipments and arrestesr located inside the building of Lightning Measurement Station at Mnt. Tangkuban Perahu. Most of the overvoltage which was developed on the low voltage lines were coming from indirect lightning strike nearby due to the fact that most of the lines were covered by trees. Research was carried out to study and evaluate the induction and conduction of the lightning strikes to the LV lines that can lead to the cause of equipment and arrester damages inside the building. Local lightning data for the analysis were derived from measurement system installed at the stations and historical lightning data from lightning detection network called Jadpen (National Lightning Detection Network. The data was used for calculating and evaluating the voltage elevation, induction voltage profiles and conduction in the form of traveling waves using Rusck Model. Two damaged arresters were evaluated and compared and it give the better understanding on how the protection system work.Keywords: 

Moengo on strike: the politics of labour in Suriname’s Bauxite industry

NARCIS (Netherlands)

de Koning, A.

2011-01-01

This article examines one crucial period of contestation in colonial Suriname, the years 1941 and 1942, when sustained labour unrest in the bauxite town of Moengo led to the establishment of the first mining unions. It argues that these strikes laid the groundwork for future relations between

[Lightning strike and lesions outside the brain: Clinical cases and a review of the literature].

Science.gov (United States)

Morin, A; Lesourd, A; Cabane, J

2015-01-01

Every year, 240,000 people are struck by lightning worldwide, causing injuries leading to significant handicaps. Most of the symptoms involve brain lesions; neuromuscular sequelae and myelopathy are less common. We describe five cases of patients struck by lightning with various clinical presentations. The first patient presented painful paresthesias in both upper limbs that disappeared 18 months later; the injury was a plexopathy. The second patient developed proximal weakness in the upper-left limb due to a myopathy. Two patients presented with various motor weaknesses in the lower limbs due to motor neuron disease and myelopathy. The last patient had a transient tetraplegy, which resolved in 5minutes; the diagnosis was keraunoparalysis. Lightning injuries can have many consequences depending on the different mechanisms involved. The clinical presentation is often due to a very focal lesion without any secondary extension. Motor neuron disease probably results from post-traumatic myelopathy. We discuss the ALS-electrocution association, frequently described in the literature. Various peripheral nerve and spinal cord lesions can be seen in lightning strike victims involving myelopathy, motor neuron, muscle and plexus. Clinical syndromes are often atypical but outcome is often favorable. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Mesozoic strike-slip movement of the Dunhua-Mishan Fault Zone in NE China: A response to oceanic plate subduction

Science.gov (United States)

Liu, Cheng; Zhu, Guang; Zhang, Shuai; Gu, Chengchuan; Li, Yunjian; Su, Nan; Xiao, Shiye

2018-01-01

The NE-striking Dunhua-Mishan Fault Zone (DMFZ) is one of two branches of the continental-scale sinistral Tan-Lu Fault Zone in NE China. The field data presented here indicate that the ca. 1000 km long DMFZ records two phases of sinistral faulting. The structures produced by these two phases of faulting include NE-SW-striking ductile shear belts and brittle faults, respectively. Mylonite-hosted microstructures and quartz c-axis fabrics suggest deformation temperatures of 450 °C-500 °C for the ductile shear belts. Combining new zircon U-Pb dates for 14 igneous rock samples analyzed during this study with the geology of this region indicates these shear belts formed during the earliest Early Cretaceous. This phase of sinistral displacement represents the initial formation of the DMFZ in response to the northward propagation of the Tan-Lu Fault Zone into NE China. A phase of Early Cretaceous rifting was followed by a second phase of sinistral faulting at 102-96 Ma, as evidenced by our new U-Pb ages for associated igneous rocks. Combining our new data with the results of previous research indicates that the DFMZ records a four-stage Cretaceous evolutionary history, where initial sinistral faulting at the beginning of the Early Cretaceous gave way to rifting during the rest of the Early Cretaceous. This was followed by a second phase of sinistral faulting at the beginning of the Late Cretaceous and a second phase of local rifting during the rest of the Late Cretaceous. The Cretaceous evolution of the DMFZ records the synchronous tectonic evolution of the NE China continent bordering the Pacific Ocean. Two phases of regional N-S compression generated the two phases of sinistral faulting within the DMFZ, whereas two-stage regional extension generated the two phases of rifting. The two compressive events were the result of the rapid low-angle subduction of the Izanagi and Pacific plates, whereas the two-stage extension was caused by the roll-back of these respective

An estimation of the impact of the 2012 platinum-sector strike on the South African economy

Directory of Open Access Journals (Sweden)

Johannes C Jordaan

2016-05-01

Full Text Available A Leontief-type economic-impact model for 2012 is used to estimate the potential impacts, in percentage terms, of the 2012 platinum-sector strike on the South African economy. Although it is impossible to incorporate and calculate all the potential impacts, such a model can provide an estimation based on sound statistics and methodologies. Understanding the potential, wider economic impacts of strike action can lead to valuable insights for policymakers, businesses and workers. This will hopefully result in improved policies, as well as enriched negotiations to find solutions to deadlocks in wage negotiations before such deadlocks progress to strike action. Data from the Department of Labour (DoL shows that 103,155 workers participated in the strike in the metal-ores sector during 2012, and company annual reports indicate that this strike action lasted seven weeks on average. Estimates show that the monetary value of ounces lost by the platinum-related mining industry as a result of lost production during the strike periods amounted to R10.6 billion. Two scenarios are estimated that result in a gross domestic product (GDP loss for 2012 of 0.53 per cent or R16.5 billion (Scenario 1, and of 0.49 per cent or R15.5 billion (Scenario 2. This implies that GDP growth could have been 3 per cent for Scenario 1 and 2.97 per cent for Scenario 2, instead of the actual GDP growth of 2.47 per cent. Exports could have been R9.05 billion higher for Scenario 1 and R8.4 billion higher for Scenario 2. The current-account deficit for 2012 could have been reduced to 4.93 per cent of GDP for Scenario 1 and to 4.9 per cent for Scenario 2, as against the actual deficit of 5.23 per cent. Tax income could have been R3.8 billion higher for Scenario 1 and R3.6 billion higher for Scenario 2. As a result, the government’s budget deficit could have been reduced to 5.13 per cent instead of 5.26 per cent. Expressing employment opportunities lost in terms of annual employment

Combining turbine blade-strike and life cycle models to assess mitigation strategies for fish passing dams

Energy Technology Data Exchange (ETDEWEB)

Ferguson, J.W. [National Marine Fisheries Service, Seattle, WA (United States). Fish Ecology Div.; Swedish Univ. of Agricultural Sciences, Umea (Sweden). Dept. of Wildlife, Fish and Environmental Studies; Ploskey, G.R. [Battelle-Pacific Northwest National Laboratory, Richland, WA (United States); Zabel, R.W. [National Marine Fisheries Service, Seattle, WA (United States). Fish Ecology Div.; Lundqvist, H. [Swedish Univ. of Agricultural Sciences, Umea (Sweden). Dept. of Wildlife, Fish and Environmental Studies

2008-08-15

Many diadromous and resident fish populations migrate within riverine, freshwater, and marine habitats that have been altered by human activities. This paper developed a tool designed to analyze the effects of dams on fish populations. The model combined a blade-strike model of a hydroelectric turbine and a life cycle model in order to generate point estimates of mortality and incorporate dam passage impacts. The modelling tool was used to study populations of Atlantic salmon and sea trout populations in Sweden which were depressed due to damming, dredging, pollution, and siltation of the rivers. The downstream migrating fish in the rivers passed through a single dam and power station containing Kaplan and Francis turbines. A blade-strike model was developed as the primary mechanism of mortality for the fish. The mortality of juvenile and adult fish and mortality rates from blade-strikes were then entered into salmon life cycle models that incorporated life history variability in age of reproduction and spawning activities. The life cycle model populations in the river were then modelled in hypothetical scenarios. Results of the scenarios were compared with effects from the blade-strike mortality results. Results of the study showed that increases in the number of female salmon escaping above the dam after 20 years was significantly higher when both juveniles and adult fish populations were protected. The model will be used to evaluate strategies designed to conserve fish populations impacted by dams. 49 refs., 9 tabs., 6 figs.

Combining turbine blade-strike and life cycle models to assess mitigation strategies for fish passing dams

International Nuclear Information System (INIS)

Ferguson, J.W.; Zabel, R.W.; Lundqvist, H.

2008-01-01

Many diadromous and resident fish populations migrate within riverine, freshwater, and marine habitats that have been altered by human activities. This paper developed a tool designed to analyze the effects of dams on fish populations. The model combined a blade-strike model of a hydroelectric turbine and a life cycle model in order to generate point estimates of mortality and incorporate dam passage impacts. The modelling tool was used to study populations of Atlantic salmon and sea trout populations in Sweden which were depressed due to damming, dredging, pollution, and siltation of the rivers. The downstream migrating fish in the rivers passed through a single dam and power station containing Kaplan and Francis turbines. A blade-strike model was developed as the primary mechanism of mortality for the fish. The mortality of juvenile and adult fish and mortality rates from blade-strikes were then entered into salmon life cycle models that incorporated life history variability in age of reproduction and spawning activities. The life cycle model populations in the river were then modelled in hypothetical scenarios. Results of the scenarios were compared with effects from the blade-strike mortality results. Results of the study showed that increases in the number of female salmon escaping above the dam after 20 years was significantly higher when both juveniles and adult fish populations were protected. The model will be used to evaluate strategies designed to conserve fish populations impacted by dams. 49 refs., 9 tabs., 6 figs

Kinematic and kinetic comparison of barefoot and shod running in mid/forefoot and rearfoot strike runners.

Science.gov (United States)

Thompson, M A; Lee, S S; Seegmiller, J; McGowan, C P

2015-05-01

Barefoot running has been associated with decreased stride length and switching from a rearfoot strike (RFS) pattern to a mid/forefoot strike (M/FFS) pattern. However, some individuals naturally contact the ground on their mid/forefoot, even when wearing cushioned running shoes. The purpose of this study was to determine if the mechanics of barefoot running by natural shod RFS runners differed from natural shod M/FFS runners. Twenty habitually shod runners (ten natural M/FFS and ten natural RFS) participated in this study. Three-dimensional motion analysis and ground reaction force data were captured as subjects ran at their preferred running speed in both barefoot and shod conditions. M/FFS experienced only a decrease in stride length when switching from shod to barefoot running. Whereas, when switching from shod to barefoot running, RFS individuals experienced a decrease in stride length, switched to a plantarflexed position at ground contact and saw reduced impact peak magnitudes. These results suggest that when barefoot, the RFS group ran similar to the M/FFS group running barefoot or shod. Copyright © 2015 Elsevier B.V. All rights reserved.

2-D Deformation analysis of a half-space due to a long dip-slip fault ...

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

tic deformation in a uniform half-space due to long faults has been attempted by a number of researchers. Singh and Rani (1996) presented step- by-step progress made in the direction of crustal deformation modeling associated with strike-slip and dip-slip faulting in the earth. Cohen (1996) gave convenient formulas for ...

Significance of heel pad confinement for the shock absorption at heel strike.

Science.gov (United States)

Jørgensen, U; Ekstrand, J

1988-12-01

Shock absorption (SA) is a simple way to reduce the body load and can be used in the prevention and treatment of injuries. The heel pad is the most important shock absorber in the shoe heel complex. The purpose of this study was to investigate whether the SA at heel strike can be increased by heel support in people and shoes with high or low SA. The impact forces at heel strike were measured on an AMTI (R) force platform. Fourteen legs were tested in seven persons (nine with normal and five with low heel pad SA) in gait analysis and in human drop tests. The tests were performed barefooted, and in a soccer and a running shoe (selected by shoe drop test), with and without the distal 2 cm of the heel counter. The heel pad confinement produced by the heel counter (the heel counter effect) increased the SA in both shoe types significantly in both impact situations. The mean increase in SA was 8.8% (range 5.8%-15.5%). The heel counter effect was in all situations significantly higher in persons with low heel pad shock absorbency (LHPSA) than in those with normal heel pads. The barefoot impact peak force per kg body weight was significantly higher (6% mean) on the side with LHPSA. The running shoe provided the significantly greatest SA compared with the soccer shoe. It is concluded that the shock absorbency at heel strike can be increased significantly by heel support, with highest effect in persons with LHPSA, both in shoes with high and low SA.(ABSTRACT TRUNCATED AT 250 WORDS)

Care around birth, infant and mother health and maternal health investments – Evidence from a nurse strike

DEFF Research Database (Denmark)

Kronborg, Hanne; Sievertsen, Hans Henrik; Wüst, Miriam

2016-01-01

Care around birth may impact child and mother health and parental health investments. We exploit the 2008 national strike among Danish nurses to identify the effects of care around birth on infant and mother health (proxied by health care usage) and maternal investments in the health...... not find strong effects of strike exposure on infant and mother GP contacts in the longer run, this result suggests that parents substitute one type of care for another. While we lack power to identify the effects of care around birth on hospital readmissions and diagnoses, our results for maternal health...... of their newborns. We use administrative data from the population register on 39,810 Danish births in the years 2007–2010 and complementary survey and municipal administrative data on 8288 births in the years 2007–2009 in a differences-in-differences framework. We show that the strike reduced the number of mothers...

Excitation of tsunami by a pure strike-slip earthquake. ; Izu Oshima kinkai earthquake tsunami on Feb. 20, 1990. Yokozure danso jishin ni yoru tsunami no reiki. ; 1990 nen 2 gatsu 20 nichi Izu Oshima kinkai jishin tsunami

Energy Technology Data Exchange (ETDEWEB)

Abe, K. (Nippon Dental University, Tokyo (Japan). Niigata Junior College); Okada, M. (Meteorological Research Institute, Tsukuba (Japan))

1993-06-24

A numerical experiment was performed to reproduce the tsunami from the Izu-Oshima Kinkai Earthquake which occurred on February 20, 1990, using a tsunami excited by a pure strike-slip fault. An existence of a vertical fault with a length of 15 km and a width of 12 km was hypothesized in the south-north direction on the ocean bottom around the focal region. Then, a tsunami was assumed to have been excited when the fault was given a side-slip movement to create discrepancies of 1 m in the fault. Water level change for one hour after onset of the tsunami was calculated in one-second interval in each unit square with a side length of 1 km over an ocean area of 200 km from east to west and 150 km from north to south centering on the wave source. The results obtained from the calculation were harmonious with tsunami waveforms observed at five stations in the subject region and their spectral analytic results. Reproduced were the two predominant frequencies commonly observed at more than two stations, and difference in predominant cycles that appear according to azimuths of the observation points to the epicenter. These facts endorse the reasonability of the above hypothesis. 9 refs., 11 figs.

Environmental Assessment: Bird Strike Risk Reduction at Laughlin Air Force Base, Texas

Science.gov (United States)

2008-01-01

mglkg in rats, 291 - 609 mglkg in mice, > 1000 mglkg in sheep , > 100 mglkg in dogs and > 1000 mglkg in rabbits (Pesticide Residues in Food-1987... vineyards . Wildl. Soc. Bull. 21:47-51. LAFB Strike Risk Reduction EA - 39 Gaines, T.B. 1969. Acute toxicity of pesticides. Toxicol. Appl. Pharmacol

On the failure behaviour to striking bow penetration of impacted marine-steel structures

Science.gov (United States)

Prabowo, Aditya Rio; Muttaqie, Teguh; Sohn, Jung Min; Bae, Dong Myung; Setiyawan, Agus

2018-04-01

Demands for water transportation modes are continuously increasing as rapid economic and industrial growths in the recent decade. Ship as representative of the water transportation is generally needed to carry various products from one location to another. Besides as product carrier, ship also acts as public facility to transport human across islands for number of reasons, such as tourism and vehicle. Considering its importance, structural damage due to accidental loads or so-called impact can cause unacceptable casualties which threat ship passenger, shipping industry and maritime environment in same time. The most frequent impact phenomena occur in forms of collision and grounding, which are targeting side structure and double bottom consecutively. However, since responses of the impacts on structure are highly nonlinear and vary due to development of ship structures, sustainable analysis as an update of pioneer calculation can be beneficial as rational reference for improving safety and navigational instruments. This work aims to assess failures of the side structures subjected to penetration of striking bow in ship-ship collision scenario. Locations of impact are idealized to happen on after-end, midsection and fore-end to provide complete assessment. Striking bow is to be deployed by varying input velocity to observe significance of the fractures on the side structure. This configuration is implemented on the designed collision scenario, and later calculated using nonlinear finite element method (NLFEM). Summary of the solution indicated that the midsection produced the highest resistance against side collision. Breaching of the inner shell was successfully avoided on the fore-end, but the critical damage to the cargo was observed during bow penetration to the after-end region. This location was recommended to be added by longitudinal framing to increase its resistance against ship collision.

On the failure behaviour to striking bow penetration of impacted marine-steel structures

Directory of Open Access Journals (Sweden)

Prabowo Aditya Rio

2018-04-01

Full Text Available Demands for water transportation modes are continuously increasing as rapid economic and industrial growths in the recent decade. Ship as representative of the water transportation is generally needed to carry various products from one location to another. Besides as product carrier, ship also acts as public facility to transport human across islands for number of reasons, such as tourism and vehicle. Considering its importance, structural damage due to accidental loads or so-called impact can cause unacceptable casualties which threat ship passenger, shipping industry and maritime environment in same time. The most frequent impact phenomena occur in forms of collision and grounding, which are targeting side structure and double bottom consecutively. However, since responses of the impacts on structure are highly nonlinear and vary due to development of ship structures, sustainable analysis as an update of pioneer calculation can be beneficial as rational reference for improving safety and navigational instruments. This work aims to assess failures of the side structures subjected to penetration of striking bow in ship-ship collision scenario. Locations of impact are idealized to happen on after-end, midsection and fore-end to provide complete assessment. Striking bow is to be deployed by varying input velocity to observe significance of the fractures on the side structure. This configuration is implemented on the designed collision scenario, and later calculated using nonlinear finite element method (NLFEM. Summary of the solution indicated that the midsection produced the highest resistance against side collision. Breaching of the inner shell was successfully avoided on the fore-end, but the critical damage to the cargo was observed during bow penetration to the after-end region. This location was recommended to be added by longitudinal framing to increase its resistance against ship collision.

Global Strike 2035: Considerations for Enabling Effective Command and Control

Science.gov (United States)

2012-02-16

reach places .1 Broadly grouped under the moniker Global Strike,2 this family-of-systems capability should mature by 2035 leading to the realization of...and] ‘micro-actors with massive impact,’…[combine] with new technology and new or transfigured ways of war, but the old threats also remain and have...as the Joint Time-Sensitive Targets Manager (JTSTM),38 “operators and analysts [could] access the same dynamic common operating picture…to provide

Three-dimensional impact kinetics with foot-strike manipulations during running

OpenAIRE

Andrew D. Nordin; Janet S. Dufek; John A. Mercer

2017-01-01

Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other axes. The purpose of the investigation was to compare three-dimensional (3D) impact kinetics among foot-strike conditions in over-ground running using instantaneous loading rate–time profiles. Methods: Impact characteristics were assessed by identifying peak loading rates in e...

Stress and slip partitioning during oblique rifting: comparison between data from the Main Ethiopian Rift and laboratory experiments

Science.gov (United States)

Corti, G.; Philippon, M.; Sani, F.; Keir, D.

2012-04-01

roughly orthogonal to the extension direction, boundary faults form oblique to the imposed stretching vector: as a group, the faults follow the rift trend, controlled by a pre-existing weak anisotropy, but individually they form oblique to both the rift margin and the extension vector. Detailed analysis of fault displacements suggest that whereas the average displacement on single internal faults is consistent with the imposed direction of extension, slip on boundary faults does not parallel this direction; the average motion on these faults is orthogonal to the faults, resulting in a roughly pure dip-slip motion. This gives rise to a marked difference in fault-slip direction between internal faults (where slip orientation follow the regional extension) and boundary faults (where displacement is oblique to the "regional" extension). A similar scenario is observed for the reconstructed direction of the minimum principal stress that follows the regional stress field within the rift and is re-oriented at rift margins. Minor counterclockwise block rotations accommodate the different slip along the different fault systems. The model-to-nature striking is striking in terms of fault orientation, stress and slip orientation and its across-axis variations. The analogue models thus allows explaining the across-axis variability observed in natural fault-slip and earthquake data. Modeling results support that boundary faults form in response to a local stress re-orientation imposed by a deep seated anisotropy: their displacement trajectories deviate from those imposed by the regional extension, resulting in a pure dip-slip motion in an overall oblique rifting kinematics, as observed in other sectors of the East African Rift. Conversely, internal faults -which form later and affect a weaker, more uniform lithosphere- respond directly to the regional extension direction resulting in a fault slip sub-parallel to the Nubia-Somalia motion. Minor counterclockwise block rotations are

Fish passage through hydropower turbines: Simulating blade strike using the discrete element method

International Nuclear Information System (INIS)

Richmond, M C; Romero-Gomez, P

2014-01-01

Among the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though hydro-turbines two common physical processes can lead to injury and mortality: collisions/blade-strike and rapid decompression. Several methods are currently available to evaluate these stressors in installed turbines, e.g. using live fish or autonomous sensor devices, and in reduced-scale physical models, e.g. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and rapid pressure change by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions-representing fish collisions with turbine components such as blades-are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for unsteady turbulence using detached eddy simulation (DES), as compared to the conventional practice of simulating the system in steady state (which was also done here for comparison). While both schemes yielded comparable bulk hydraulic performance values, transient conditions exhibited an improvement in describing flow temporal and spatial variability. We released streamtraces (in the steady flow solution) and DEM particles (transient solution) at the same locations where sensor fish (SF) were released in previous field studies of the advanced turbine unit. The streamtrace- based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the

Laboratory demonstration of lightning strike pattern on different roof tops installed with Franklin Rods

Science.gov (United States)

Ullah, Irshad; Baharom, MNR; Ahmed, H.; Luqman, HM.; Zainal, Zainab

2017-11-01

Protection against lightning is always a challenging job for the researcher. The consequences due to lightning on different building shapes needs a comprehensive knowledge in order to provide the information to the common man. This paper is mainly concern with lightning pattern when it strikes on the building with different shape. The work is based on the practical experimental work in high voltage laboratory. Different shapes of the scaled structures have been selected in order to investigate the equal distribution of lightning voltage. The equal distribution of lightning voltage will provide the maximum probability of lightning strike on air terminal of the selected shapes. Building shapes have a very important role in lightning protection. The shapes of the roof tops have different geometry and the Franklin rod installation is also varies with changing the shape of the roof top. According to the ambient weather condition of Malaysia high voltage impulse is applied on the lightning rod installed on different geometrical shape. The equal distribution of high voltage impulse is obtained as the geometry of the scaled structure is identical and the air gap for all the tested object is kept the same. This equal distribution of the lightning voltage also proves that the probability of lightning strike is on the corner and the edges of the building structure.

Seismicity of the Earth 1900–2010 Himalaya and vicinity

Science.gov (United States)

Turner, Bethan; Jenkins, Jennifer; Turner, Rebecca; Parker, Amy; Sinclair, Alison; Davies, Sian; Hayes, Gavin P.; Villaseñor, Antonio; Dart, Rirchard L.; Tarr, Arthur C.; Furlong, Kevin P.; Benz, Harley M.

2013-01-01

Seismicity in the Himalaya region predominantly results from the collision of the India and Eurasia continental plates, which are converging at a relative rate of 40–50 mm/yr. Northward underthrusting of India beneath Eurasia generates numerous earthquakes and consequently makes this area one of the most seismically hazardous regions on Earth. The surface expression of the plate boundary is marked by the foothills of the north-south trending Sulaiman Range in the west, the Indo-Burmese Arc in the east, and the east-west trending Himalaya Front in the north of India. Along the western margin of the India plate, relative motions between India and Eurasia are accommodated by strike-slip, reverse, and oblique-slip faulting resulting in the complex Sulaiman Range fold and thrust belt, and the major translational Chaman Fault in Afghanistan. Beneath the Pamir‒Hindu Kush Mountains of northern Afghanistan, earthquakes occur to depths as great as 200 km as a result of remnant lithospheric subduction. Further north again, the Tian Shan is a seismically active intra-continental mountain belt defined by a series of east-west trending thrust faults thought to be related to the broad footprint of the India-Eurasia collision. Tectonics in northern India are dominated by motion along the Main Frontal Thrust and associated thrust faults of the India-Eurasia plate boundary, which have resulted in a series of large and devastating earthquakes in (and prior to) the 20th century. The Tibetan Plateau to the north of the main plate boundary is a broad region of uplift associated with the India-Eurasia collision, and is cut by a series of generally east-west trending strike-slip faults. These include the Kunlun, Haiyuan, and the Altyn Tagh faults, all of which are left-lateral structures, and the Kara-Koram right-lateral fault. Throughout the plateau, thrust faults accommodate the north-south compressional component of crustal shortening associated with the ongoing collision of India

F-35 Lightning II Joint Strike Fighter (JSF) Program: Background, Status, and Issues

National Research Council Canada - National Science Library

Bolkcom, Christopher; Murch, Anthony

2008-01-01

The Defense Department's F-35 Lightning II Joint Strike Fighter (JSF) is one of three aircraft modernization programs in tactical aviation, the others being the Air Force F-22A fighter and the Navy F/A-18E/F fighter/attack plane...

F-35 Lightning II Joint Strike Fighter "JSF" Program: Background, Status, and Issues

National Research Council Canada - National Science Library

Murch, Anthony; Bolkcom, Christopher

2007-01-01

The Defense Department's F-35 Lightning II Joint Strike Fighter (JSF) is one of three aircraft modernization programs in tactical aviation, the others being the Air Force F-22A fighter and the Navy F/A-18E/F fighter/attack plane...

F-35 Lightning II Joint Strike Fighter (JSF) Program: Background, Status, and Issues

National Research Council Canada - National Science Library

Bolkcom, Christopher

2009-01-01

The Defense Department's F-35 Lightning II Joint Strike Fighter (JSF) is one of three aircraft modernization programs in tactical aviation, the others being the Air Force F-22A fighter and the Navy F/A-18E/F fighter/attack plane...

Traumatic neuralgia from pressure-point strikes in the martial arts: results from a retrospective online survey.

Science.gov (United States)

Kelly, Michael D

2008-06-01

Many techniques in Asian martial arts hand-to-hand combat systems emphasize hitting or striking specific sites on the body that correlate with exposed portions of peripheral nerves. To evaluate the prevalence and clinical effects of this unique sports-related injury. An anonymous self-administered retrospective 20-question electronic survey was posted on a high-traffic martial arts Web site. Primary outcome measures were demographic and medical history data, including martial arts experience and neuropathic symptoms associated with injury from this form of combat. Risk of symptoms was calculated by dividing the number of individuals with symptoms in each pressure-point area by the number of individuals who were struck in these areas during martial arts training. Of the 651 survey responses received, 605 met inclusion criteria. Neuropathic symptoms were reported by 291 subjects. Most symptoms occurred in individuals aged between 20 and 30 years as well as in individuals with less than 1 year of martial arts training. The majority of respondents with neuropathic symptoms reported a symptom duration of less than 1 year (207 [71%]). Individuals with more than 5 years of combat training experience had a greater risk of chronic symptoms than individuals with less experience. Strikes to pressure points on the back had the greatest risk of inducing neuropathic symptoms. Symptoms of neurapraxia can occur in individuals as a result of practicing martial arts involving strikes on pressure points. Although the majority of symptoms resolve within 1 year, individuals with prolonged exposure to pressure-point strikes may be more likely to have chronic symptoms.

Fabrication and assessment of a thin flexible surface coating made of pristine graphene for lightning strike protection

Energy Technology Data Exchange (ETDEWEB)

Zhang, B. [Department of Mechanical Engineering, Wichita State University, 1845 Fairmount St., Wichita, KS 67260-0133 (United States); Soltani, S.A. [Department of Aerospace Engineering, Wichita State University, 1845 Fairmount St., Wichita, KS 67260-0133 (United States); Le, L.N. [Department of Mechanical Engineering, Wichita State University, 1845 Fairmount St., Wichita, KS 67260-0133 (United States); Asmatulu, R., E-mail: ramazan.asmatulu@wichita.edu [Department of Mechanical Engineering, Wichita State University, 1845 Fairmount St., Wichita, KS 67260-0133 (United States)

2017-02-15

A thin flexible coating made of pristine graphene was fabricated and applied on the surface of a commercial carbon fiber epoxy prepreg laminate to protect it against the lightning strike. To assess the coating’s effectiveness, the coated laminate was subjected to the simulated lightning strike as well as the electromagnetic interference shielding effectiveness (EMI SE) testing. It was observed that the damaged area and volume in the coated laminate were reduced by 94% and 96%, respectively, as compared to the laminate without the coating. Moreover, the coated laminate had an average EMI SE of 51 dB over 100–2000 MHz range, 55 dB over 8–12 GHz range, and 60 dB over 12–18 GHz range marking 22%, 44%, and 49% improvement in EMI SE for each frequency range, respectively. The results indicate a great potential for the developed coating to protect the commercially available prepreg composites against the lightning strike.

Fabrication and assessment of a thin flexible surface coating made of pristine graphene for lightning strike protection

International Nuclear Information System (INIS)

Zhang, B.; Soltani, S.A.; Le, L.N.; Asmatulu, R.

2017-01-01

A thin flexible coating made of pristine graphene was fabricated and applied on the surface of a commercial carbon fiber epoxy prepreg laminate to protect it against the lightning strike. To assess the coating’s effectiveness, the coated laminate was subjected to the simulated lightning strike as well as the electromagnetic interference shielding effectiveness (EMI SE) testing. It was observed that the damaged area and volume in the coated laminate were reduced by 94% and 96%, respectively, as compared to the laminate without the coating. Moreover, the coated laminate had an average EMI SE of 51 dB over 100–2000 MHz range, 55 dB over 8–12 GHz range, and 60 dB over 12–18 GHz range marking 22%, 44%, and 49% improvement in EMI SE for each frequency range, respectively. The results indicate a great potential for the developed coating to protect the commercially available prepreg composites against the lightning strike.

Short-term changes in running mechanics and foot strike pattern after introduction to minimalistic footwear.

Science.gov (United States)

Willson, John D; Bjorhus, Jordan S; Williams, D S Blaise; Butler, Robert J; Porcari, John P; Kernozek, Thomas W

2014-01-01

Minimalistic footwear has garnered widespread interest in the running community, based largely on the premise that the footwear may reduce certain running-related injury risk factors through adaptations in running mechanics and foot strike pattern. To examine short-term adaptations in running mechanics among runners who typically run in conventional cushioned heel running shoes as they transition to minimalistic footwear. A 2-week, prospective, observational study. A movement science laboratory. Nineteen female runners with a rear foot strike (RFS) pattern who usually train in conventional running shoes. The participants trained for 20 minutes, 3 times per week for 2 weeks by using minimalistic footwear. Three-dimensional lower extremity running mechanics were analyzed before and after this 2-week period. Hip, knee, and ankle joint kinematics at initial contact; step length; stance time; peak ankle joint moment and joint work; impact peak; vertical ground reaction force loading rate; and foot strike pattern preference were evaluated before and after the intervention. The knee flexion angle at initial contact increased 3.8° (P < .01), but the ankle and hip flexion angles at initial contact did not change after training. No changes in ankle joint kinetics or running temporospatial parameters were observed. The majority of participants (71%), before the intervention, demonstrated an RFS pattern while running in minimalistic footwear. The proportion of runners with an RFS pattern did not decrease after 2 weeks (P = .25). Those runners who chose an RFS pattern in minimalistic shoes experienced a vertical loading rate that was 3 times greater than those who chose to run with a non-RFS pattern. Few systematic changes in running mechanics were observed among participants after 2 weeks of training in minimalistic footwear. The majority of the participants continued to use an RFS pattern after training in minimalistic footwear, and these participants experienced higher

Lightning Strike Ablation Damage Influence Factors Analysis of Carbon Fiber/Epoxy Composite Based on Coupled Electrical-Thermal Simulation

Science.gov (United States)

Yin, J. J.; Chang, F.; Li, S. L.; Yao, X. L.; Sun, J. R.; Xiao, Y.

2017-10-01

According to the mathematical analysis model constructed on the basis of energy-balance relationship in lightning strike, and accompany with the simplified calculation strategy of composite resin pyrolysis degree dependent electrical conductivity, an effective three dimensional thermal-electrical coupling analysis finite element model of composite laminate suffered from lightning current was established based on ABAQUS, to elucidate the effects of lighting current waveform parameters and thermal/electrical properties of composite laminate on the extent of ablation damage. Simulated predictions agree well with the composite lightning strike directed effect experimental data, illustrating the potential accuracy of the constructed model. The analytical results revealed that extent of composite lightning strike ablation damage can be characterized by action integral validly, there exist remarkable power function relationships between action integral and visual damage area, projected damage area, maximum damage depth and damage volume of ablation damage, and enhancing the electrical conductivity and specific heat of composite, ablation damage will be descended obviously, power function relationships also exist between electrical conductivity, specific heat and ablation damage, however, the impact of thermal conductivity on the extent of ablation damage is not notable. The conclusions obtained provide some guidance for composite anti-lightning strike structure-function integration design.

Acoustic Emission Monitoring of Compression-after-Impact Test of Nano-Particles-Coated CFRP Damaged by Simulated Lightning Strikes

Energy Technology Data Exchange (ETDEWEB)

Shin, Je Ha; Kwon, Oh Yang; Seo, Seong Wook [Inha University, Incheon (Korea, Republic of)

2011-02-15

Nanoparticles-coated and impact-damaged carbon-fiber reinforced plastics(CFRP) laminates were tested under compression-after-impact(CAI) mode and the propagation of damage due to compressive loading has been monitored by acoustic emission(AE). The impact damage was induced not by mechanical loading but by a simulated lightning strike. CFRP laminates were made of carbon prepregs prepared by coating of conductive nano-particles directly on the fibers and the coupons were subjected to simulated lightning strikes with a high voltage/current impulse of 10{approx}40 kA within a few microseconds. The effects of nano-particles coating and the degree of damage induced by the simulated lightning strikes on the AE activities were examined, and the relationship between the compressive residual strength and AE behavior has been evaluated in terms of AE event counts and the onset of AE activity with the compressive loading. The degree of impact damage was also measured in terns of damage area by using ultrasonic C-scan images. From the results assessed during the CAI tests of damaged CFRP showed that AE monitoring appeared to be very useful to differentiate the degree of damage hence the mechanical integrity of composite structures damaged by lightning strikes

Acoustic Emission Monitoring of Compression-after-Impact Test of Nano-Particles-Coated CFRP Damaged by Simulated Lightning Strikes

International Nuclear Information System (INIS)

Shin, Je Ha; Kwon, Oh Yang; Seo, Seong Wook

2011-01-01

Nanoparticles-coated and impact-damaged carbon-fiber reinforced plastics(CFRP) laminates were tested under compression-after-impact(CAI) mode and the propagation of damage due to compressive loading has been monitored by acoustic emission(AE). The impact damage was induced not by mechanical loading but by a simulated lightning strike. CFRP laminates were made of carbon prepregs prepared by coating of conductive nano-particles directly on the fibers and the coupons were subjected to simulated lightning strikes with a high voltage/current impulse of 10∼40 kA within a few microseconds. The effects of nano-particles coating and the degree of damage induced by the simulated lightning strikes on the AE activities were examined, and the relationship between the compressive residual strength and AE behavior has been evaluated in terms of AE event counts and the onset of AE activity with the compressive loading. The degree of impact damage was also measured in terns of damage area by using ultrasonic C-scan images. From the results assessed during the CAI tests of damaged CFRP showed that AE monitoring appeared to be very useful to differentiate the degree of damage hence the mechanical integrity of composite structures damaged by lightning strikes

A survey of the prevalence of blowfly strike and the control measures used in the Rûens area of the Western Cape Province of South Africa

Directory of Open Access Journals (Sweden)

A. J. Scholtz

2011-04-01

Full Text Available Blowfly strike and the methods used to combat blowfly strike were recorded on 33 properties in the Rûens area of South Africa during 2003/2004. Data were recorded on Merino and Dohne Merino hoggets (n = 4951 with at least 3 months’ wool growth. The following data were captured: presence or absence of strike, site of the strike (body or breech, presence or absence of dermatophilosis as well as subjective scores for wool quality and wool colour. Control measures recorded include: chemical treatment (preventative and spot treatment, crutching, mulesing and the use of the Lucitrap® system. Blowfly strike was not significantly influenced by gender or breed. Hoggets suffering from dermatophilosis were more likely to be struck, compared with contemporaries not suffering from the skin disorder (0.057 vs 0.027; P < 0.05. Merino hoggets generally had higher scores than their Dohne Merino contemporaries for wool quality (32.6 vs 27.4; P<0.05 and wool colour (29.0 vs 27.2; P<0.05. There was an indication that the Lucitrap® system may have reduced flystrike, but the effect was not statistically significant (P = 0.19 for overall strikes and P = 0.12 for body strike. The Mules operation benefited overall flystrike (0.013 vs 0.110; P < 0.05; mainly through an effect on breech strike (0.010 vs 0.109; P < 0.05. The proportion of fly strikes increased with wool length, and declined with an increase in farm size in wool colour score. None of the ethically acceptable control measures assessed could substantially reduce blowfly strike on their own, and an integrated pest management programme was proposed.

Is there evidence to support a forefoot strike pattern in barefoot runners? A review.

Science.gov (United States)

Lorenz, Daniel S; Pontillo, Marisa

2012-11-01

Barefoot running is a trend among running enthusiasts that is the subject of much controversy. At this time, benefits appear to be more speculative and anecdotal than evidence based. Additionally, the risk of injuries is not well established. A PubMed search was undertaken for articles published in English from 1980 to 2011. Additional references were accrued from reference lists of research articles. While minimal data exist that definitively support barefoot running, there are data lending support to the argument that runners should use a forefoot strike pattern in lieu of a heel strike pattern to reduce ground reaction forces, ground contact time, and step length. Whether there is a positive or negative effect on injury has yet to be determined. Unquestionably, more research is needed before definitive conclusions can be drawn.

Oscillation thresholds for "striking outwards" reeds coupled to a resonator

OpenAIRE

Silva , Fabrice; Kergomard , Jean; Vergez , Christophe

2007-01-01

International audience; This paper considers a "striking outwards" reed coupled to a resonator. This expression, due to Helmholtz, is not discussed here : it corresponds to the most common model of a lip-type valve, when the valve is assumed to be a one degree of freedom oscillator. The presented work is an extension of the works done by Wilson and Beavers (1974), Tarnopolsky (2000). The range of the playing frequencies is investigated. The first results are analytical : when no losses are pr...

An integrated approach to the probabilistic assessments of aircraft strikes and structural mode of damages to nuclear power plants

International Nuclear Information System (INIS)

Godbout, P.; Brais, A.

1975-01-01

The possibilities of an aircraft striking a Canadian nuclear power plant in the vicinity of an airport and of inducing structural failure modes have been evaluated. This evaluation, together with other studies, may enhance decisions in the development of general criteria for the siting of reactors near airports. The study made use, for assessment, of the probabilistic approach and made judicious applications of the finite Canadian, French, German, American and English resources that were available. The tools, techniques and methods used for achieving the above, form what may be called an integrated approach. This method of approach requires that the study be made in six consecutive steps as follows: the qualitative evaluation of having an aircraft strike on a site situated near an airport with the use of the logic model technique; the statistical data gathering on aircraft movements and accidents; evaluating the probability distribution and calculating the basic event probabilities; evaluating the probability of an aircraft strike and the application of the sensitivity approach; generating the probability density distribution versus strike impact energy, that is, the evaluation of the energy envelope; and the probabilistic evaluation of structural failure mode inducements

Combined effects of magnetic field and partial slip on obliquely striking rheological fluid over a stretching surface

International Nuclear Information System (INIS)

Nadeem, S.; Mehmood, Rashid; Akbar, Noreen Sher

2015-01-01

This study explores the collective effects of partial slip and transverse magnetic field on an oblique stagnation point flow of a rheological fluid. The prevailing momentum equations are designed by manipulating Casson fluid model. By applying the suitable similarity transformations, the governing system of equations is being transformed into coupled nonlinear ordinary differential equations. The resulting system is handled numerically through midpoint integration scheme together with Richardson's extrapolation. It is found that both normal and tangential velocity profiles decreases with an increase in magnetic field as well as slip parameter. Streamlines pattern are presented to study the actual impact of slip mechanism and magnetic field on the oblique flow. A suitable comparison with the previous literature is also provided to confirm the accuracy of present results for the limiting case. - Highlights: • The MHD 2-Dimensional flow of Casson fluid is present. • Streamlines pattern are presented to study the actual impact of slip mechanism and magnetic field on the oblique flow. • The prevailing momentum equations are designed by manipulating Casson fluid model. • Obtained coupled ordinary differential equations are investigated numerically. • Graphical results are obtained for each physical parameter

A Pressure Plate-Based Method for the Automatic Assessment of Foot Strike Patterns During Running.

Science.gov (United States)

Santuz, Alessandro; Ekizos, Antonis; Arampatzis, Adamantios

2016-05-01

The foot strike pattern (FSP, description of how the foot touches the ground at impact) is recognized to be a predictor of both performance and injury risk. The objective of the current investigation was to validate an original foot strike pattern assessment technique based on the numerical analysis of foot pressure distribution. We analyzed the strike patterns during running of 145 healthy men and women (85 male, 60 female). The participants ran on a treadmill with integrated pressure plate at three different speeds: preferred (shod and barefoot 2.8 ± 0.4 m/s), faster (shod 3.5 ± 0.6 m/s) and slower (shod 2.3 ± 0.3 m/s). A custom-designed algorithm allowed the automatic footprint recognition and FSP evaluation. Incomplete footprints were simultaneously identified and corrected from the software itself. The widely used technique of analyzing high-speed video recordings was checked for its reliability and has been used to validate the numerical technique. The automatic numerical approach showed a good conformity with the reference video-based technique (ICC = 0.93, p < 0.01). The great improvement in data throughput and the increased completeness of results allow the use of this software as a powerful feedback tool in a simple experimental setup.

Geodynamics and Stress State of the Earth's Crust in the Greater and Lesser Caucasus (Azerbaijan) collision region

Science.gov (United States)

Babayev, Gulam; Akhmedova, Elnare; Babayev, Elvin

2017-04-01

The current study researches the present-day stress state of the Earth's crust within the territory of Azerbaijan by using the database of the international research project "World Stress Map" (WSM). The present stress state was also assessed by exploring the effects of the contemporary topographic properties of Caucasus in three-dimensional frame. Aiming to explore the relative roles of regional tectonic conditions in the definition of stress state of Greater and Lesser Caucasus, stress distribution model was developed by the earthquake data (1998-2016) and by the standard techniques of stress field calculation. The results show that the stress orientations are influenced also by the combination of topography and crust thickness distribution even at very large depth. Stress data and earthquake focal mechanisms indicate that the stress state of the Earth's crust of the Greater and Lesser Caucasus is characterized by the compression predominantly oriented across the regional strike. The model results suggest that the Lesser Caucasus and Kur depression are rotating coherently, with little or no internal deformation in a counter-clockwise rotation located near the north-eastern corner of the Black Sea. Orientation of stress axes well consistent with earthquake focal mechanisms revealed that within Upper and Lower Crusts, earthquakes are predominantly thrust-faulting with a number of normal-faulting and some strike-slip faulting. The map of the focal mechanisms and stress distribution suggests that the research area is characterized by the thrust of horizontal compression trending north-north-east in the western part of the southern Caucasus. In the western part of Azerbaijan, the compression takes place between the Main Caucasus Fault and the Kur depression, which strikes south along the northern margin of the mountain range. In addition, a clear transition from the left-lateral strike slip to the predominantly right-lateral strike slip is observed in the southern of

Feasibility of Observing and Characterizing Single Ion Strikes in Microelectronic Components

International Nuclear Information System (INIS)

Dingreville, Remi Philippe Michel; Hattar, Khalid Mikhiel; Bufford, Daniel Charles

2015-01-01

The transient degradation of semiconductor device performance under irradiation has long been an issue of concern. A single high-energy charged particle can degrade or permanently destroy the microelectronic component, potentially altering the course or function of the systems. Disruption of the the crystalline structure through the introduction of quasi-stable defect structures can change properties from semiconductor to conductor. Typically, the initial defect formation phase is followed by a recovery phase in which defect-defect or defect-dopant interactions modify the characteristics of the damaged structure. In this LDRD Express, in-situ ion irradiation transmission microscopy (TEM) in-situ TEM experiments combined with atomistic simulations have been conducted to determine the feasibility of imaging and characterizing the defect structure resulting from a single cascade in silicon. In-situ TEM experiments have been conducted to demonstrate that a single ion strike can be observed in Si thin films with nanometer resolution in real time using the in-situ ion irradiation transmission electron microscope (I 3 TEM). Parallel to this experimental effort, ion implantation has been numerically simulated using Molecular Dynamics (MD). This numerical framework provides detailed predictions of the damage and follow the evolution of the damage during the first nanoseconds. The experimental results demonstrate that single ion strike can be observed in prototypical semiconductors.

Style and rate of quaternary deformation of the Hosgri Fault Zone, offshore south-central coastal California

Science.gov (United States)

Hanson, Kathryn L.; Lettis, William R.; McLaren, Marcia; Savage, William U.; Hall, N. Timothy; Keller, Mararget A.

2004-01-01

The Hosgri Fault Zone is the southernmost component of a complex system of right-slip faults in south-central coastal California that includes the San Gregorio, Sur, and San Simeon Faults. We have characterized the contemporary style of faulting along the zone on the basis of an integrated analysis of a broad spectrum of data, including shallow high-resolution and deep penetration seismic reflection data; geologic and geomorphic data along the Hosgri and San Simeon Fault Zones and the intervening San Simeon/Hosgri pull-apart basin; the distribution and nature of near-coast seismicity; regional tectonic kinematics; and comparison of the Hosgri Fault Zone with worldwide strike-slip, oblique-slip, and reverse-slip fault zones. These data show that the modern Hosgri Fault Zone is a convergent right-slip (transpressional) fault having a late Quaternary slip rate of 1 to 3 mm/yr. Evidence supporting predominantly strike-slip deformation includes (1) a long, narrow, linear zone of faulting and associated deformation; (2) the presence of asymmetric flower structures; (3) kinematically consistent localized extensional and compressional deformation at releasing and restraining bends or steps, respectively, in the fault zone; (4) changes in the sense and magnitude of vertical separation both along trend of the fault zone and vertically within the fault zone; (5) strike-slip focal mechanisms along the fault trace; (6) a distribution of seismicity that delineates a high-angle fault extending through the seismogenic crust; (7) high ratios of lateral to vertical slip along the fault zone; and (8) the separation by the fault of two tectonic domains (offshore Santa Maria Basin, onshore Los Osos domain) that are undergoing contrasting styles of deformation and orientations of crustal shortening. The convergent component of slip is evidenced by the deformation of the early-late Pliocene unconformity. In characterizing the style of faulting along the Hosgri Fault Zone, we assessed

Intra-Continental Deformation by Mid-Crustal Shearing and Doming in a Cenozoic Compressive Setting Along the Ailao Shan-Red River Shear Zone

Science.gov (United States)

Zhang, B.

2016-12-01

Large-scale lateral strike-slip shear zones have been a key point in the debate about the deformation mechanisms of Asia in response to the India-Asia collision. The exhumed gneiss has been attributed to lateral strike-slip shear zone. This hypothesis has been challenged by recent discoveries indicating that a contractional doming deformation prior to the initiation of lateral strike-slip shearing. The Cenozoic Xuelong Shan antiformal dome is located at the northern segment of the Ailao Shan-Red River shear zone. Subhorizontal foliation in the gneiss core are recognized, representing a broad top-to-NE shear initiated under amphibolite facies conditions and propagated into greenschist facies in the mantling schist and strike-slip shear zone. Quartz CPOs and opening angles of crossed girdle fabrics in quartz suggest that the deformation temperatures increased with increasing structural depth from 300-500 °C in the mantling schist to ≥650 °C in the gneissic core. This trend is mirrored by variations in the metamorphic grade of the syn-kinematic mineral assemblages and microstructures, which ranges from garnet + amphibole + biotite + sillimanite + rutite + feldspar in the core to garnet + staurolite + biotite + epidote + muscovite within the limb units. Five-stage deformation is identified: (1) a broad top-to-NE shear in the subhorizontal level (D1); (2) opposing reverse-sense shear along the two schist limbs of the dome during contraction-related doming (D2-D3); (3) sinistral strike-slip shearing within the eastern limb (D4); and (4) extensional deformation (D5). The antiformal dome formation had been roughly coeval with top-to-NE ductile shearing in the mid-crust at 32 Ma or earlier. The geometries of the antiformal dome in the Xuelong Shan dome are similar to those associated with the antiform in the Dai Nui Con Voi, Diancang Shan and Ailao Shan zones. It is likely that the complex massifs, which define a regional linear gneiss dome zone in Cenozoic intra

Buried shallow fault slip from the South Napa earthquake revealed by near-field geodesy.

Science.gov (United States)

Brooks, Benjamin A; Minson, Sarah E; Glennie, Craig L; Nevitt, Johanna M; Dawson, Tim; Rubin, Ron; Ericksen, Todd L; Lockner, David; Hudnut, Kenneth; Langenheim, Victoria; Lutz, Andrew; Mareschal, Maxime; Murray, Jessica; Schwartz, David; Zaccone, Dana

2017-07-01

Earthquake-related fault slip in the upper hundreds of meters of Earth's surface has remained largely unstudied because of challenges measuring deformation in the near field of a fault rupture. We analyze centimeter-scale accuracy mobile laser scanning (MLS) data of deformed vine rows within ±300 m of the principal surface expression of the M (magnitude) 6.0 2014 South Napa earthquake. Rather than assuming surface displacement equivalence to fault slip, we invert the near-field data with a model that allows for, but does not require, the fault to be buried below the surface. The inversion maps the position on a preexisting fault plane of a slip front that terminates ~3 to 25 m below the surface coseismically and within a few hours postseismically. The lack of surface-breaching fault slip is verified by two trenches. We estimate near-surface slip ranging from ~0.5 to 1.25 m. Surface displacement can underestimate fault slip by as much as 30%. This implies that similar biases could be present in short-term geologic slip rates used in seismic hazard analyses. Along strike and downdip, we find deficits in slip: The along-strike deficit is erased after ~1 month by afterslip. We find no evidence of off-fault deformation and conclude that the downdip shallow slip deficit for this event is likely an artifact. As near-field geodetic data rapidly proliferate and will become commonplace, we suggest that analyses of near-surface fault rupture should also use more sophisticated mechanical models and subsurface geomechanical tests.

Buried shallow fault slip from the South Napa earthquake revealed by near-field geodesy

Science.gov (United States)

Brooks, Benjamin A.; Minson, Sarah E.; Glennie, Craig L.; Nevitt, Johanna M.; Dawson, Tim; Rubin, Ron; Ericksen, Todd L.; Lockner, David; Hudnut, Kenneth; Langenheim, Victoria; Lutz, Andrew; Mareschal, Maxime; Murray, Jessica; Schwartz, David; Zaccone, Dana

2017-01-01

Earthquake-related fault slip in the upper hundreds of meters of Earth’s surface has remained largely unstudied because of challenges measuring deformation in the near field of a fault rupture. We analyze centimeter-scale accuracy mobile laser scanning (MLS) data of deformed vine rows within ±300 m of the principal surface expression of the M (magnitude) 6.0 2014 South Napa earthquake. Rather than assuming surface displacement equivalence to fault slip, we invert the near-field data with a model that allows for, but does not require, the fault to be buried below the surface. The inversion maps the position on a preexisting fault plane of a slip front that terminates ~3 to 25 m below the surface coseismically and within a few hours postseismically. The lack of surface-breaching fault slip is verified by two trenches. We estimate near-surface slip ranging from ~0.5 to 1.25 m. Surface displacement can underestimate fault slip by as much as 30%. This implies that similar biases could be present in short-term geologic slip rates used in seismic hazard analyses. Along strike and downdip, we find deficits in slip: The along-strike deficit is erased after ~1 month by afterslip. We find no evidence of off-fault deformation and conclude that the downdip shallow slip deficit for this event is likely an artifact. As near-field geodetic data rapidly proliferate and will become commonplace, we suggest that analyses of near-surface fault rupture should also use more sophisticated mechanical models and subsurface geomechanical tests. PMID:28782026

Tectonic implications of the 2017 Ayvacık (Çanakkale) earthquakes, Biga Peninsula, NW Turkey

Science.gov (United States)

Özden, Süha; Över, Semir; Poyraz, Selda Altuncu; Güneş, Yavuz; Pınar, Ali

2018-04-01

The west to southwestward motion of the Anatolian block results from the relative motions between the Eurasian, Arabian and African plates along the right-lateral North Anatolian Fault Zone in the north and left-lateral East Anatolian Fault Zone in the east. The Biga Peninsula is tectonically influenced by the Anatolian motion originating along the North Anatolian Fault Zone which splits into two main (northern and southern) branches in the east of Marmara region: the southern branch extends towards the Biga Peninsula which is characterized by strike-slip to oblique normal faulting stress regime in the central to northern part. The southernmost part of peninsula is characterized by a normal to oblique faulting stress regime. The analysis of both seismological and structural field data confirms the change of stress regime from strike-slip character in the center and north to normal faulting character in the south of peninsula where the earthquake swarm recently occurred. The earthquakes began on 14 January 2017 (Mw: 4.4) on Tuzla Fault and migrated southward along the Kocaköy and Babakale's stepped-normal faults of over three months. The inversion of focal mechanisms yields a normal faulting stress regime with an approximately N-S (N4°E) σ3 axis. The inversion of earthquakes occurring in central and northern Biga Peninsula and the north Aegean region gives a strike-slip stress regime with approximately WNW-ESE (N85°W) σ1 and NNE-SSW (N17°E) σ3 axis. The strike-slip stress regime is attributed to westward Anatolian motion, while the normal faulting stress regime is attributed to both the extrusion of Anatolian block and the slab-pull force of the subducting African plate along the Hellenic arc.

Gait training reduces ankle joint stiffness and facilitates heel strike in children with Cerebral Palsy

DEFF Research Database (Denmark)

Willerslev-Olsen, Maria; Lorentzen, Jakob; Nielsen, Jens Bo

2014-01-01

and facilitate heel strike in children with CP? METHODS: Seventeen children with CP (4-14 years) were recruited. Muscle stiffness and gait ability were measured twice before and twice after training with an interval of one month. Passive and reflex-mediated stiffness were measured by a dynamometer which applied...... in stiffness following training (P = 0.01). Toe lift in the swing phase (P = 0.014) and heel impact (P = 0.003) increased significantly following the training during both treadmill and over-ground walking. CONCLUSIONS: Daily intensive gait training may influence the elastic properties of ankle joint muscles...... and facilitate toe lift and heel strike in children with CP. Intensive gait training may be beneficial in preventing contractures and maintain gait ability in children with CP....

Angles of total shifts and angles of maxumum crop during development of faces diagonal to seam strike directions

Directory of Open Access Journals (Sweden)

Н. А. Колесник

2017-06-01

Full Text Available When predicting deformations and determining measures to protect underworked objects, angular parameters are used: the boundary angles, the angles of total shift, the angle of maximum crop. The values of these angular parameters are given in the normative documents, but only for sections across and along the strike of the formation. However, at present, longwall face mining is mainly being carried out along a diagonal direction to the strike of the formation. In connection with this, the determination of the values of the angular parameters for such conditions is a topical task.The method of determination and the analytical dependences of the angles of total shifts and angles of maximum crop in sections of the longitudinal and transverse axes of coal-mining faces developed along diagonal directions to the strike of the formation are proposed. These angular parameters are used for prognosis of deformations of the earth's surface and for determining the characteristic zones of influence of mine workings on the local places.

Short-and-long-term Slip Rates Along the Carboneras Fault in the Betic Cordillera, Spain

Science.gov (United States)

Khazaradze, G.; López, R.; Pallàs, R.; Ortuño, M.; Bordonau, J.; Masana, E.

2017-12-01

We present the new results from our long-standing studies to understand the geodynamic behavior of the Carboneras fault, located in the SE Betic Cordilleras of Spain. Specifically, we quantify the geodetic and geologic slip rates for the onland section of the fault. As a result of our previous GPS observations, we have been able to confirm the continuing tectonic activity of the Carboneras fault: we were able to quantify that the geodetic slip rate of the fault equals 1.3±0.2 mm/yr, expressed mainly as a left-lateral strike slip motion (Echeverria et al., 2015). In autumn 2017, with the purpose of revealing a detailed nature of the crustal deformation and its partitioning between different structures, 3 new continuous GPS stations will be established along the fault-perpendicular profile. In addition, since summer 2016, we have conducted surveys of the nearby CuaTeNeo and IGN Regente campaign points. We have also established and measured several new geodetic points in the vicinity of the fault, with the aim of increasing the spatial coverage around it. The GPS measured, short-term slip rates are in surprising agreement with the estimates of the long-term, geologic slip rates based on paleoseismic studies, which indicate a minimum strike-slip rate of 1.31 mm/yr and dip-slip rate of 0.05 mm/yr since 110.3 ka (Moreno et al. 2015). In order to increase the paleoseismic event database, several new sites have been identified along the fault, where further paleoseismic trenching surveys will be performed within the coming year or two. At the site of Tostana, located at the central part of the fault, in winter 2017 seven trenches have been opened and clear evidence of past earthquakes has been encountered. These new data, combined with the findings of the recent geomorphological study of river offsets (Ferrater, 2016) and new GPS observations, should improve the reliability of the existent deformation data and therefore, will help to better understand the seismic hazard

3-D structure of the crust and uppermost mantle at the junction between the Southeastern Alps and External Dinarides from ambient noise tomography

Science.gov (United States)

Guidarelli, Mariangela; Aoudia, Abdelkrim; Costa, Giovanni

2017-12-01

We use ambient noise tomography to investigate the crust and the uppermost mantle structure beneath the junction between the Southern Alps, the Dinarides and the Po Plain. We obtained Rayleigh wave empirical Green's functions from cross-correlation of vertical component seismic recordings for three years (2010-2012) using stations from networks in Italy, Slovenia, Austria, Croatia, Serbia and Switzerland. We measure group and phase velocity dispersion curves from the reconstructed Rayleigh waves in the period range 5-30 and 8-37 s, respectively, and we invert the surface wave velocities for tomographic images on a grid of 0.1° × 0.1°. After the tomography, the group velocities are then inverted to compute the 3-D shear wave velocity model of the crust and the upper mantle beneath the region. Our shear wave velocity model provides the 3-D image of the structure in the region between Northeastern Italy, Slovenia and Austria. The velocity variations at shallow depths correlate with known geological and tectonic domains. We find low velocities below the Po Plain, the northern tip of the Adriatic and the Pannonian Basin, whereas higher velocities characterize the Alpine chain. The vertical cross-sections reveal a clear northward increase of the crustal thickness with a sharp northward dipping of the Moho that coincides at the surface with the leading edge of the Alpine thrust front adjacent to the Friuli Plain in Northeastern Italy. This geometry of the Moho mimics fairly well the shallow north dipping geometry of the decollement inferred from permanent GPS velocity field where high interseismic coupling is reported. From the northern Adriatic domain up to the Idrija right lateral strike-slip fault system beneath Western Slovenia, the crustal thickness is more uniform. Right across Idrija fault, to the northeast, and along its strike, we report a clear change of the physical properties of the crust up to the uppermost mantle as reflected by the lateral distribution

Recent strikes in South Africa’s platinum-group metal mines: effects upon world platinum-group metal supplies

Science.gov (United States)

Yager, Thomas R.; Soto-Viruet, Yadira; Barry, James J.

2012-01-01

The recent labor disputes over wages and working conditions that have affected South Africa’s three leading platinum-group metal (PGM) producers have affected an industry already plagued by market pressures and labor unrest and raised the specter of constraints in the world’s supply of these metals. Although low demand for these metals in 2011 and 2012 helped to offset production losses of recent years, and particularly those losses caused by the strikes in 2012, a prolonged resumption of strikes could cause severe shortages of iridium, platinum, rhodium, ruthenium, and, to a lesser extent, palladium.

Mass and performance optimization of an airplane wing leading edge structure against bird strike using Taguchi-based grey relational analysis

Directory of Open Access Journals (Sweden)

Hassan Pahange

2016-08-01

Full Text Available Collisions between birds and aircraft are one of the most dangerous threats to flight safety. In this study, smoothed particles hydrodynamics (SPH method is used for simulating the bird strike to an airplane wing leading edge structure. In order to verify the model, first, experiment of bird strike to a flat aluminum plate is simulated, and then bird impact on an airplane wing leading edge structure is investigated. After that, considering dimensions of wing internal structural components like ribs, skin and spar as design variables, we try to minimize structural mass and wing skin deformation simultaneously. To do this, bird strike simulations to 18 different wing structures are made based on Taguchi’s L18 factorial design of experiment. Then grey relational analysis is used to minimize structural mass and wing skin deformation due to the bird strike. The analysis of variance (ANOVA is also applied and it is concluded that the most significant parameter for the performance of wing structure against impact is the skin thickness. Finally, a validation simulation is conducted under the optimal condition to show the improvement of performance of the wing structure.

Changes in Kicking Pattern: Effect of Experience, Speed, Accuracy, and Effective Striking Mass

Science.gov (United States)

Southard, Dan L.

2014-01-01

Purpose: The purposes of this study were to: (a) examine the effect of experience and goal constraints (speed, accuracy) on kicking patterns; (b) determine if effective striking mass was independent of ankle velocity at impact; and (c) determine the accuracy of kicks relative to independent factors. Method: Twenty participants were recruited to…

Extreme-Strike and Small-time Asymptotics for Gaussian Stochastic Volatility Models

OpenAIRE

Zhang, Xin

2016-01-01

Asymptotic behavior of implied volatility is of our interest in this dissertation. For extreme strike, we consider a stochastic volatility asset price model in which the volatility is the absolute value of a continuous Gaussian process with arbitrary prescribed mean and covariance. By exhibiting a Karhunen-Loève expansion for the integrated variance, and using sharp estimates of the density of a general second-chaos variable, we derive asymptotics for the asset price density for large or smal...

Using Whatman FTA® Cards to Collect DNA for Bird-Strike Identifications

OpenAIRE

Dove, Carla J.; Dahlan, Nor Faridah; Heacker, Marcy A.; Whatton, James F.

2011-01-01

Identification of species of birds is fundamental to implementation of all management and mitigation issues involving bird–aircraft collisions (bird strikes). Methods of identifying bird remains have recently been enhanced to include the use of molecular techniques but the degraded condition of the fi eld sample remains problematic. The Whatman FTA® card is a novel way to instantly fi x DNA and inhibit degradation of DNA samples post-collection. During 2008–2009, we analyzed >200 FTA cards co...

Spatial Variation of Slip Behavior Beneath the Alaska Peninsula Along Alaska-Aleutian Subduction Zone

Science.gov (United States)

Li, Shanshan; Freymueller, Jeffrey T.

2018-04-01

We resurveyed preexisting campaign Global Positioning System (GPS) sites and estimated a highly precise GPS velocity field for the Alaska Peninsula. We use the TDEFNODE software to model the slip deficit distribution using the new GPS velocities. We find systematic misfits to the vertical velocities from the optimal model that fits the horizontal velocities well, which cannot be explained by altering the slip distribution, so we use only the horizontal velocities in the study. Locations of three boundaries that mark significant along-strike change in the locking distribution are identified. The Kodiak segment is strongly locked, the Semidi segment is intermediate, the Shumagin segment is weakly locked, and the Sanak segment is dominantly creeping. We suggest that a change in preexisting plate fabric orientation on the downgoing plate has an important control on the along-strike variation in the megathrust locking distribution and subduction seismicity.

The Evaluation Method of the Lightning Strike on Transmission Lines Aiming at Power Grid Reliability

Science.gov (United States)

Wen, Jianfeng; Wu, Jianwei; Huang, Liandong; Geng, Yinan; Yu, zhanqing

2018-01-01

Lightning protection of power system focuses on reducing the flashover rate, only distinguishing by the voltage level, without considering the functional differences between the transmission lines, and being lack of analysis the effect on the reliability of power grid. This will lead lightning protection design of general transmission lines is surplus but insufficient for key lines. In order to solve this problem, the analysis method of lightning striking on transmission lines for power grid reliability is given. Full wave process theory is used to analyze the lightning back striking; the leader propagation model is used to describe the process of shielding failure of transmission lines. The index of power grid reliability is introduced and the effect of transmission line fault on the reliability of power system is discussed in detail.

Negative ion beam characterisation in BATMAN by mini-STRIKE: Improved design and new measurements

Science.gov (United States)

Serianni, G.; Bonomo, F.; Brombin, M.; Cervaro, V.; Chitarin, G.; Cristofaro, S.; Delogu, R.; De Muri, M.; Fasolo, D.; Fonnesu, N.; Franchin, L.; Franzen, P.; Ghiraldelli, R.; Molon, F.; Muraro, A.; Pasqualotto, R.; Ruf, B.; Schiesko, L.; Tollin, M.; Veltri, P.

2015-04-01

The ITER project requires additional heating provided by two injectors of neutral beams resulting from the neutralisation of accelerated negative ions. To study and optimise negative ion production, the SPIDER test facility (particle energy 100keV; beam current 50A) is under construction in Padova, with the aim of testing beam characteristics and to verify the source proper operation. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon fibre carbon composite tiles. Some prototype tiles have been employed in 2012 as a small-scale version (mini-STRIKE) of the entire system to investigate the features of the beam from BATMAN at IPP-Garching. As the BATMAN beamlets are superposed at the measurement position, about 1m from the grounded grid, an actively cooled copper mask is located in front of the tiles; holes in the mask create an artificial beamlet structure. Recently the mini-STRIKE has been updated, taking into account the results obtained in the first campaign. In particular the spatial resolution of the system has been improved by increasing the number of the copper mask holes. Moreover a custom measurement system has been realized for the thermocouple signals and employed in BATMAN in view of its use in SPIDER. The present contribution gives a description of the new design of the system as well as of the thermocouple measurements system and its field test. A new series of measurements has been carried out in BATMAN. The BATMAN beam characterisation in different experimental conditions is presented.

Negative ion beam characterisation in BATMAN by mini-STRIKE: Improved design and new measurements

International Nuclear Information System (INIS)

Serianni, G.; Brombin, M.; Cervaro, V.; Chitarin, G.; Delogu, R.; Fasolo, D.; Fonnesu, N.; Franchin, L.; Ghiraldelli, R.; Molon, F.; Pasqualotto, R.; Tollin, M.; Veltri, P.; Bonomo, F.; Cristofaro, S.; De Muri, M.; Franzen, P.; Ruf, B.; Schiesko, L.; Muraro, A.

2015-01-01

The ITER project requires additional heating provided by two injectors of neutral beams resulting from the neutralisation of accelerated negative ions. To study and optimise negative ion production, the SPIDER test facility (particle energy 100keV; beam current 50A) is under construction in Padova, with the aim of testing beam characteristics and to verify the source proper operation. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon fibre carbon composite tiles. Some prototype tiles have been employed in 2012 as a small-scale version (mini-STRIKE) of the entire system to investigate the features of the beam from BATMAN at IPP-Garching. As the BATMAN beamlets are superposed at the measurement position, about 1m from the grounded grid, an actively cooled copper mask is located in front of the tiles; holes in the mask create an artificial beamlet structure. Recently the mini-STRIKE has been updated, taking into account the results obtained in the first campaign. In particular the spatial resolution of the system has been improved by increasing the number of the copper mask holes. Moreover a custom measurement system has been realized for the thermocouple signals and employed in BATMAN in view of its use in SPIDER. The present contribution gives a description of the new design of the system as well as of the thermocouple measurements system and its field test. A new series of measurements has been carried out in BATMAN. The BATMAN beam characterisation in different experimental conditions is presented

Variations in strength and slip rate along the san andreas fault system.

Science.gov (United States)

Jones, C H; Wesnousky, S G

1992-04-03

Convergence across the San Andreas fault (SAF) system is partitioned between strike-slip motion on the vertical SAF and oblique-slip motion on parallel dip-slip faults, as illustrated by the recent magnitude M(s) = 6.0 Palm Springs, M(s) = 6.7 Coalinga, and M(s) = 7.1 Loma Prieta earthquakes. If the partitioning of slip minimizes the work done against friction, the direction of slip during these recent earthquakes depends primarily on fault dip and indicates that the normal stress coefficient and frictional coefficient (micro) vary among the faults. Additionally, accounting for the active dip-slip faults reduces estimates of fault slip rates along the vertical trace of the SAF by about 50 percent in the Loma Prieta and 100 percent in the North Palm Springs segments.

Role of Transtension in Rifting at the Pacific-North America Plate Boundary

Science.gov (United States)

Stock, J. M.

2011-12-01

Transtensional plate motion can be accommodated either in a localized zone of transtensional rifting or over a broader region. Broader zones of deformation can be classified either as diffuse deformation or strain partitioning (one or more major strike-slip shear zones geographically offset from a region of a extensional faulting). The Pacific-North America plate boundary in southwestern North America was transtensional during much of its history and has exhibited the full range of these behaviors at different spatial scales and in different locations, as recorded by fault motions and paleomagnetic rotations. Here we focus on the northern Gulf of California part of the plate boundary (Upper and Lower Delfin basin segments), which has been in a zone of transtensional Pacific-North America plate boundary motion ever since the middle Miocene demise of adjacent Farallon-derived microplates. Prior to the middle Miocene, during the time of microplate activity, this sector of North America experienced basin-and-range normal faults (core complexes) in Sonora. However there is no evidence of continued extensional faulting nor of a Gulf-related topographic depression until after ca 12 Ma when a major ignimbrite (Tuff of San Felipe/ Ignimbrite of Hermosillo) was deposited across the entire region of the future Gulf of California rift in this sector. After 12 Ma, faults disrupted this marker bed in eastern Baja California and western Sonora, and some major NNW-striking right-lateral faults are inferred to have developed near the Sonoran coast causing offset of some of the volcanic facies. However, there are major tectonic rotations of the volcanic rocks in NE Baja California between 12 and 6 Ma, suggesting that the plate boundary motion was still occurring over a broad region. By contrast, after about 6 Ma, diminished rotations in latest Miocene and Pliocene volcanic rocks, as well as fault slip histories, show that plate boundary deformation became localized to a narrower

Annotated Bibliography of Bird Hazards to Aircraft: Bird Strike Committee Citations 1967-1997.

Science.gov (United States)

1998-03-01

birds. The products are completely biodegradable in aerobic and anaerobic environments and do not accumulate in the environment. No significant...strike database for 1976-1990 were analyzed and presented as an aerodrome digest showing trends in performance for each airport. The objective was...Carrion Garbage Invertebrates Vegetative Vertebrates Lighting Landfills (rubbish tips) Loafing/Safe Areas Roosts Sewage Slaughterhouses

Structural and microstructural evolution of fault zones in Cretaceous poorly lithified sandstones of the Rio do Peixe basin, Paraiba, NE Brazil

Science.gov (United States)

Balsamo, Fabrizio; Nogueira, Francisco; Storti, Fabrizio; Bezerra, Francisco H. R.; De Carvalho, Bruno R.; André De Souza, Jorge

2017-04-01

are arranged in conjugate system consisting of NNW-SSE- and WNW-ESE-trending fault zones with left-lateral and right-lateral kinematics, respectively. Compared to extensional fault zones, strike-slip fault zones have narrow fault cores (few cm thick) and up to 2-3 m-thick damage zones. Microstructural observations indicate that cataclasis with pervasive grain size reduction is the dominant deformation mechanisms within the fault core, thus suggesting that late-stage strike-slip faulting occurred when sandstones were partially lithified by diagenetic processes. Alternatively, the change in deformation mechanisms may indicate faulting at greater depth. Structural and microstructural data suggest that fault zones in the Rio do Peixe basin developed in a progression from "ductile" (sensu Rutter, 1986) to more "brittle" deformation during changes from extensional to strike-slip kinematic fields. Such rheological and stress configuration evolution is expected to impact the petrophysical and permeability structure of fault zones in the study area.

A pedestrian dead-reckoning system that considers the heel-strike and toe-off phases when using a foot-mounted IMU

Science.gov (United States)

Ju, Hojin; Lee, Min Su; Park, So Young; Song, Jin Woo; Park, Chan Gook

2016-01-01

In this paper, we propose an advanced pedestrian dead-reckoning (PDR) algorithm that considers the heel-strike and toe-off phases. Generally, PDR systems that use a foot-mounted inertial measurement unit are based on an inertial navigation system with an extended Kalman filter (EKF). To reduce the influence of the bias and white noises in the gyroscope and accelerometer signals, a zero-velocity update is often adopted at the stance phase. However, transient and large acceleration, which cannot be measured by the accelerometer used in pedestrian navigation, occur momentarily in the heel-strike phase. The velocity information from integration of the acceleration is not reliable because the acceleration is not measured in the heel-strike phase. Therefore, the designed EKF does not correctly reflect the actual environment, because conventional algorithms do not take the non-measurable acceleration into consideration. In order to reflect the actual environment, we propose a PDR system that considers the non-measurable acceleration from the heel-strike impact. To improve the PDR system’s performance, the proposed algorithm uses a new velocity measurement obtained using the constraint between the surface and the foot during the toe-off phase. The experimental results show improved filter performance after comparison of the proposed algorithm and a conventional algorithm.

A pedestrian dead-reckoning system that considers the heel-strike and toe-off phases when using a foot-mounted IMU

International Nuclear Information System (INIS)

Ju, Hojin; Lee, Min Su; Park, So Young; Park, Chan Gook; Song, Jin Woo

2016-01-01

In this paper, we propose an advanced pedestrian dead-reckoning (PDR) algorithm that considers the heel-strike and toe-off phases. Generally, PDR systems that use a foot-mounted inertial measurement unit are based on an inertial navigation system with an extended Kalman filter (EKF). To reduce the influence of the bias and white noises in the gyroscope and accelerometer signals, a zero-velocity update is often adopted at the stance phase. However, transient and large acceleration, which cannot be measured by the accelerometer used in pedestrian navigation, occur momentarily in the heel-strike phase. The velocity information from integration of the acceleration is not reliable because the acceleration is not measured in the heel-strike phase. Therefore, the designed EKF does not correctly reflect the actual environment, because conventional algorithms do not take the non-measurable acceleration into consideration. In order to reflect the actual environment, we propose a PDR system that considers the non-measurable acceleration from the heel-strike impact. To improve the PDR system’s performance, the proposed algorithm uses a new velocity measurement obtained using the constraint between the surface and the foot during the toe-off phase. The experimental results show improved filter performance after comparison of the proposed algorithm and a conventional algorithm. (paper)

Evolution of the stress fields in the Zagros Foreland Folded Belt using focal mechanisms and kinematic analyses: the case of the Fars salient, Iran

Science.gov (United States)

Sarkarinejad, Khalil; Zafarmand, Bahareh; Oveisi, Behnam

2018-03-01

The NW-SE trending Zagros orogenic belt was initiated during the convergence of the Afro-Arabian continent and the Iranian microcontinent in the Late Cretaceous. Ongoing convergence is confirmed by intense seismicity related to compressional stresses collision-related in the Zagros orogenic belt by reactivation of an early extensional faulting to latter compressional segmented strike-slip and dip-slip faulting. These activities are strongly related either to the deep-seated basement fault activities (deep-seated earthquakes) underlies the sedimentary cover or gently dipping shallow-seated décollement horizon of the rheological weak rocks of the infra-Cambrian Hormuz salt. The compressional stress regimes in the different units play an important role in controlling the stress conditions between the different units within the sedimentary cover and basement. A significant set of nearly N-S trending right-lateral strike-slip faults exists throughout the study area in the Fars area in the Zagros Foreland Folded Belt. Fault-slip and focal mechanism data were analyzed using the stress inversion method to reconstruct the paleo and recent stress conditions. The results suggest that the current direction of maximum principal stress averages N19°E, with N38°E that for the past from Cretaceous to Tertiary (although a few sites on the Kar-e-Bass fault yield a different direction). The results are consistent with the collision of the Afro-Arabian continent and the Iranian microcontinent. The difference between the current and paleo-stress directions indicates an anticlockwise rotation in the maximum principle stress direction over time. This difference resulted from changes in the continental convergence path, but was also influenced by the local structural evolution, including the lateral propagation of folds and the presence of several local décollement horizons that facilitated decoupling of the deformation between the basement and the sedimentary cover. The obliquity of

Misbheaving Faults: The Expanding Role of Geodetic Imaging in Unraveling Unexpected Fault Slip Behavior

Science.gov (United States)