Hydraulic servo system increases accuracy in fatigue testing

Hydraulic servo system increases accuracy in applying fatigue loading to a specimen under test. An error sensing electronic control loop, coupled to the hydraulic proportional closed loop cyclic force generator, provides an accurately controlled peak force to the specimen

Phase operators, phase states and vector phase states for SU(3) and SU(2,1)

This paper focuses on phase operators, phase states and vector phase states for the sl(3) Lie algebra. We introduce a one-parameter generalized oscillator algebra A(k,2) which provides a unified scheme for dealing with su(3) (for k < 0), su(2,1) (for k > 0) and h(4) x h(4) (for k = 0) symmetries. Finite- and infinite-dimensional representations of A(k,2) are constructed for k < 0 and k > 0 or = 0, respectively. Phase operators associated with A(k,2) are defined and temporally stable phase states (as well as vector phase states) are constructed as eigenstates of these operators. Finally, we discuss a relation between quantized phase states and a quadratic discrete Fourier transform and show how to use these states for constructing mutually unbiased bases

Bases for qudits from a nonstandard approach to SU(2)

Bases of finite-dimensional Hilbert spaces (in dimension d) of relevance for quantum information and quantum computation are constructed from angular momentum theory and su(2) Lie algebraic methods. We report on a formula for deriving in one step the (1+p)p qupits (i.e., qudits with d = p a prime integer) of a complete set of 1+p mutually unbiased bases in C^p. Repeated application of the formula can be used for generating mutually unbiased bases in C^d with d = p^e (e > or = 2) a power of a prime integer. A connection between mutually unbiased bases and the unitary group SU(d) is briefly discussed in the case d = p^e.Comment: From a talk presented at the 13th International Conference on Symmetry Methods in Physics (Dubna, Russia, 6-9 July 2009) organized in memory of Prof. Yurii Fedorovich Smirnov by the Bogoliubov Laboratory of Theoretical Physics of the JINR and the ICAS at Yerevan State University

Determination of ASPS performance for large payloads in the shuttle orbiter disturbance environment

A high fidelity simulation of the annular suspension and pointing system (ASPS), its payload, and the shuttle orbiter was used to define the worst case orientations of the ASPS and its payload for the various vehicle disturbances, and to determine the performance capability of the ASPS under these conditions. The most demanding and largest proposed payload, the Solar Optical Telescope was selected for study. It was found that, in all cases, the ASPS more than satisfied the payload's requirements. It is concluded that, to satisfy facility class payload requirements, the ASPS or a shuttle orbiter free-drift mode (control system off) should be utilized

Sum Rules for Multi-Photon Spectroscopy of Ions in Finite Symmetry

Models describing one- and two-photon transitions for ions in crystalline environments are unified and extended to the case of parity-allowed and parity- forbidden p-photon transitions. The number of independent parameters for characterizing the polarization dependence is shown to depend on an ensemble of properties and rules which combine symmetry considerations and physical models.Comment: 16 pages, Tex fil

Application of a local linearization technique for the solution of a system of stiff differential equations associated with the simulation of a magnetic bearing assembly

A digital local linearization technique was used to solve a system of stiff differential equations which simulate a magnetic bearing assembly. The results prove the technique to be accurate, stable, and efficient when compared to a general purpose variable order Adams method with a stiff option

Archeological Investigations and National Register Testing at 41CV1636, Coryell County, Texas

Prewitt and Associates, Inc. (PAI), conducted archeological testing of 41CV1636 for the Texas Department of Transportation (TxDOT), Environmental Affairs Division, under Contract No. 575XXSA006 (Work Authorization No. 57530SA006) and Texas Antiquities Permit No. 3980 from the Texas Historical Commission. Site 41CV1636 is situated in northwestern Coryell County, approximately 13 km east of Evant, Texas. The site was located during an archeological survey for a proposed roadway widening project along U.S. Highway 84. Proposed design plans required an additional 5 m of new right of way that would directly impact 41CV1636. Site 41CV1636 is a prehistoric site buried in Holocene alluvium of a relict channel of Cowhouse Creek. At this location, Cowhouse Creek has a ca. 1.5-km-wide stretch of Holocene alluvium. Archeological testing consisted of the excavation of two backhoe trenches and four 1x1-m hand-dug units. All sediments were water-screened. Excavations recovered a rather large lithic assemblage and two burned rock features: a partially dismantled slab-lined, basin-shaped hearth and a possible burned rock discard pile or stockpile. The recovery of Pedernales and Provisional Type 1 projectile point forms argues for a multicomponent occupation during portions of the early Late Archaic Period; however, only one analysis unit could be defined. The alluvial deposits at 41CV1636 appear correlative to the Fort Hood and West Range alluvium identified by other researchers along downstream portions of Cowhouse Creek on the Fort Hood military reservation. Soil stratigraphy at the site indicates that cultural occupations occurred as floodplain aggradation slowed and soil development began. Sedimentation via overbank flooding and colluvial deposition continued at a pace quick enough to impose some vertical separation between multiple occupations that occurred during a short time span. Poor preservation of organic remains has been a hindrance to providing good temporal control at the site. The lack of radiocarbon ages and poor preservation mean that few substantial statements can be made regarding chronology or subsistence. 41CV1636 is considered ineligible for the National Register of Historic Places or as a designated State Archeological Landmark, and no further work is warranted for this site

Archeological Investigations and National Register Testing at 41CV163, Coryell County, Texas

Prewitt and Associates, Inc. (PAI), conducted archeological testing of 41CV1636 for the Texas Department of Transportation (TxDOT), Environmental Affairs Division, under Contract No. 575XXSA006 (Work Authorization No. 57530SA006) and Texas Antiquities Permit No. 3980 from the Texas Historical Commission. Site 41CV1636 is situated in northwestern Coryell County, approximately 13 km east of Evant, Texas. The site was located during an archeological survey for a proposed roadway widening project along U.S. Highway 84. Proposed design plans required an additional 5 m of new right of way that would directly impact 41CV1636. Site 41CV1636 is a prehistoric site buried in Holocene alluvium of a relict channel of Cowhouse Creek. At this location, Cowhouse Creek has a ca. 1.5-km-wide stretch of Holocene alluvium. Archeological testing consisted of the excavation of two backhoe trenches and four 1x1-m hand-dug units. All sediments were water-screened. Excavations recovered a rather large lithic assemblage and two burned rock features: a partially dismantled slab-lined, basin-shaped hearth and a possible burned rock discard pile or stockpile. The recovery of Pedernales and Provisional Type 1 projectile point forms argues for a multicomponent occupation during portions of the early Late Archaic Period; however, only one analysis unit could be defined. The alluvial deposits at 41CV1636 appear correlative to the Fort Hood and West Range alluvium identified by other researchers along downstream portions of Cowhouse Creek on the Fort Hood military reservation. Soil stratigraphy at the site indicates that cultural occupations occurred as floodplain aggradation slowed and soil development began. Sedimentation via overbank flooding and colluvial deposition continued at a pace quick enough to impose some vertical separation between multiple occupations that occurred during a short time span. Poor preservation of organic remains has been a hindrance to providing good temporal control at the site. The lack of radiocarbon ages and poor preservation mean that few substantial statements can be made regarding chronology or subsistence. 41CV1636 is considered ineligible for the National Register of Historic Places or as a designated State Archeological Landmark, and no further work is warranted for this site

National Register Testing at 41BQ285, Bosque County, Texas: FM 56 Bridge Replacement at the North Bosque River

Prewitt and Associates, Inc., conducted archeological test excavations at 41BQ285 in June 2006 for the Texas Department of Transportation under Texas Antiquities Permit No. 4102. Site 41BQ285, in southeastern Bosque County, was located during an archeological survey for the proposed replacement of the FM 56 bridge over the North Bosque River. It is a prehistoric campsite buried in a cumulic soil in the upper deposits of a late Holocene alluvial terrace. Mechanical excavations consisted of re-opening four backhoe trenches from the survey phase followed by hand excavation of six 1x1-m test units. This work identified three burned rock features and yielded a moderate amount of materials, including projectile points and bifaces, pottery sherds, unmodified debitage, vertebrate faunal remains, and freshwater mussel shells. Diagnostic artifacts and five radiocarbon ages indicate that the site has a lower but rather ephemeral Late Archaic component and an upper and more substantial Late Prehistoric component. The Late Prehistoric component yielded Perdiz arrow points and ceramics, and it is radiocarbon dated to between a.d. 1280 and 1650. The evidence suggests a series of relatively short occupations and a focus on the use of local resources. Site activities included late-stage biface reduction and bifacial tool production, tool resharpening, and the exploitation and intensive processing of deer. Foodstuffs were processed and prepared using bifacial tools, ground and battered stone tools, rock-lined cooking basins, and small ceramic jars and bowls. The Late Prehistoric component is Toyah-like in many ways, but the small sample size and nature of the materials preclude assigning it a specific sociocultural group or archeological phase. Of particular interest are the five pottery sherds—two plain, two fingernail punctate, and one engraved sherd from a carinated bowl with a Caddo-like design. Geochemical analysis indicates that none of the pottery, including the engraved bowl sherd, matches any Caddo-made pottery from East Texas. The fact that a Caddo vessel form and decorative style appears on pottery that was probably made in or near Bosque County is interesting and adds a new dynamic to our understanding of the Toyah phenomenon in central Texas. The portion of site 41BQ285 within FM 56 is considered eligible for listing in the National Register of Historic Places (NRHP) or for designation as a State Archeological Landmark (SAL). However, current investigations already recovered most of the Late Prehistoric component within the spatially limited project area, and additional investigations inside the highway right of way cannot reasonably be expected to contribute any more significant archeological information. Therefore, no further fieldwork is recommended, and construction should be allowed to proceed

Val Verde on the Sunny Rio Grande Geoarcheological and Historical Investigations at San Felipe Springs, Val Verde County, Texas

In the fall of 1997, Prewitt and Associates, Inc. conducted archival and oral history research, an archeological survey, and National Register testing of a prehistoric site in the vicinity of the San Felipe Springs in southeastern Val Verde County, Texas. The work was done in preparation for construction of a water treatment plant and related facilities for the City of Del Rio. The survey resulted in the recording of one historic site (41VV1820) and further documentation of historic and prehistoric components at a previously known site, 41VV444. The latter site also was the focus of intensive geoarcheological investigations. National Register testing of 41VV444, called the San Felipe Springs site, was restricted to portions of the alluvial terraces of San Felipe Creek near the East and West San Felipe Springs. A 40-m\u27 block excavation near the East Springs revealed three stratified prehistoric components in the upper ca. 100 m of alluvium. These sediments represent continual deposition over the last 3,000-4,000 years, and archeological materials denoting Late Prehistoric, Protohistoric, Late Archaic, and Middle Archaic occupations were recovered. The upper component post-dates A.D. 1300 and produced plain bone-tempered potsherds, ClifIton and Perdiz arrow points, and steeply beveled scrapers. This component represents a Toyah phase occupation on the western periphery of the Toyah culture area, but it shares many attributes with Protohistoric Infierno phase occupations of the Lower Pecos. The middle component is characterized by Shumla dart points and three pit features originating near the base of a dense burned rock layer. It represents utilization of the area during the Flanders Subperiod of the Late Archaic. Although recovered from many sites (particularly rockshelters), the chronology of Shumla points is not well established in the region. Radiocarbon assays place the age of the San Felipe Springs Shumla component at ca. 800-200 B.C. Geomorphic evidence suggests that a major flood episode (or episodes) occurred along San Felipe Creek between ca. 1300 and 800 B.C. This gravelly deposit separates the middle component from the lower component and is indicative of a high volume flood event, possibly similar to the August 1998 flooding along San Felipe Creek resulting from Hurricane Charley. Underlying this zone is a discrete Middle Archaic occupation containing a dense burned rock layer and an internal pit feature. Radiocarbon dates, along with associated Bulverde and Langtry variant dart points, correlate to the San Felipe Subperiod. Also associated with this occupation is a small concentration of artifacts representing a dump or cache of usable lithic materials. Historic components at 41VV1820 and 41VV444 contain structures related to the City of Del Rio\u27s water pumping and distribution system. These resources, particularly the East Springs pump house and pond enclosure at 41VV444, are historically significant; however, they will be removed during construction of new water pumping facilities. Site 41VV444 encompasses most of what is now the San Felipe Country Club golfcourse. Built by Texas\u27 first golfcourse architect, John Bredemus, in 1922, the San Felipe course is now recognized as an important historic landscape