bluuebunny/crossref_metadata_2025 huggingface dataset:
The Annual Cycle of Circulation of the Southwest Subtropical Pacific, Analyzed in an Ocean GCM*
Authors: Kessler William S. , Gourdeau Lionel
Published: June 2007

An ocean GCM, interpreted in light of linear models and sparse observations, is used to diagnose the dynamics of the annual cycle of circulation in the western boundary current system of the southwest Pacific Ocean. The simple structure of annual wind stress curl over the South Pacific produces a large region of uniformly phased, stationary thermocline depth anomalies such that the western subtropical gyre spins up and down during the year, directing flow anomalies alternately toward and away from the boundary at its northern end, near 10°S. The response of the western boundary currents is to redistribute these anomalies northward toward the equator and southward to the subtropical gyre, a redistribution that is determined principally by linear Rossby processes, not boundary dynamics. When the subtropical gyre and South Equatorial Current (SEC) are strong (in the second half of the year), the result is both increased equatorward transport of the New Guinea Coastal Current and poleward transport anomalies along the entire Australian coast. Because of this opposite phasing of boundary current anomalies across 10°S, annual migration of the bifurcation point of the total SEC, near 18°S in the mean, has no significance regarding variability of transport from subtropics to equator.
Interaction of a Coastal Kelvin Wave with the Mean State in the Gulf Stream Separation Area
Authors: Février Sabine , Sirven Jérôme , Herbaut Christophe
Published: June 2007

The interaction of a coastal Kelvin wave with the mean state in the Gulf Stream separation area is studied using a hierarchy of numerical models including both low- and high-resolution 2.5-layer models and a coarse-resolution ocean general circulation model (OGCM) in a simple configuration. When the Kelvin front reaches the separation area in the low-resolution 2.5-layer model, an anomaly of opposite sign emerges and remains in the upper layer of the separation area. The mechanism leading to its buildup is the following: the variations of thickness in the active midlayer due to the propagation of the Kelvin wave induce current variations that act as a source of thickness anomalies for the upper layer (negative feedback). This source term is proportional to the mean vorticity gradient. The latter therefore must be large enough to obtain a significant response, which explains why this phenomenon occurs only in the separation area. The anomaly remains in the separation area because the advection by the mean zonal current is balanced by the current anomalies due to the variations of thickness in the surface layer. A very similar response is obtained in the high-resolution case and with the OGCM; thus, the mechanism leading to this evolution seems also largely independent of the model. However, in the OGCM, the surface current is sufficiently strong to advect the anomaly in the surface layers (above 200-m depth). Note finally that these anomalies do not prevent the Kelvin waves from pursuing their travel southward and then eastward toward the eastern boundary where Rossby waves are radiated. Numerous recent results based on this adjustment mechanism therefore would be robust.
Origin and Composition of Seasonal Labrador Sea Freshwater
Authors: Schmidt Sunke , Send Uwe
Published: June 2007

The depth of winter convection in the central Labrador Sea is strongly influenced by the prevailing stratification in late summer. For this late summer stratification salinity is as important as temperature, and in the upper water layers salinity even dominates. To analyze the source of the spring and summer freshening in the central region, seasonal freshwater cycles have been constructed for the interior Labrador Sea, the West Greenland Current, and the Labrador Current. It is shown that none of the local freshwater sources is responsible for the spring–summer freshening in the interior, which appears to occur in two separate events in April to May and July to September. Comparing the timing and volume estimates of the seasonal freshwater cycles of the boundary currents with the central Labrador Sea helps in understanding the origin of the interior freshwater signals. The first smaller pulse cannot be attributed clearly to either of the boundary currents. The second one is about three times stronger and supplies 60% of the seasonal summer freshwater. Transport estimates and calculated mixing properties provide evidence that its source is the West Greenland Current. The finding implies a connection also on interannual time scales between Labrador Sea surface salinity and freshwater sources in the West Greenland Current and farther upstream in the East Greenland Current. The freshwater input from the West Greenland Current thus also is the likely pathway for the known modulation of Labrador Sea Water mass formation by freshwater export from the Arctic (via the East Greenland Current), which implies some predictability on longer time scales.
Is the Loop Current a Chaotic Oscillator?
Authors: Lugo-Fernández Alexis
Published: June 2007

Dynamical systems theory is employed to study the irregular Loop Current in the Gulf of Mexico using a short database of shedding periods and north–south positions of the current. Two independent tests based on these data suggest that the Loop Current is not chaotic but behaves as a nonlinear driven and dampened oscillator with a very short memory. It is suggested that this current varies around a limit-cycle elliptical attractor. It was found that the amplitude and period of the oscillation vary at time scales of 3–5 yr, a time scale that agrees with those of the North Atlantic Oscillation (NAO) and/or ENSO; however, it is proposed that NAO provides the link between these systems. The proposed mechanism is the ITCZ changes caused by NAO, which affects the wind strength and the transport across the Yucatan Channel. A forecasting scheme that allows for prediction of the next eddy-shedding period from knowledge of the last shedding event, a condition caused by the short memory of the system, is provided.
Cascade Inequalities for Forced–Dissipated Geostrophic Turbulence
Authors: Arbic Brian K. , Flierl Glenn R. , Scott Robert B.
Published: June 2007

Analysis of spectral kinetic energy fluxes in satellite altimetry data has demonstrated that an inverse cascade of kinetic energy is ubiquitous in the ocean. In geostrophic turbulence models, a fully developed inverse cascade results in barotropic eddies with large horizontal scales. However, midocean eddies contain substantial energy in the baroclinic mode and in compact horizontal scales (scales comparable to the deformation radius Ld). This paper examines the possibility that relatively strong bottom friction prevents the oceanic cascade from becoming fully developed. The importance of the vertical structure of friction is demonstrated by contrasting numerical simulations of two-layer quasigeostrophic turbulence forced by a baroclinically unstable mean flow and damped by bottom Ekman friction with turbulence damped by vertically symmetric Ekman friction (equal decay rates in the two layers). “Cascade inequalities” derived from the energy and enstrophy equations are used to interpret the numerical results. In the symmetric system, the inequality formally requires a cascade to large-scale barotropic flow, independent of the stratification. The inequality is less strict when friction is in the bottom layer only, especially when stratification is surface intensified. Accordingly, model runs with surface-intensified stratification and relatively strong bottom friction retain substantial small-scale baroclinic energy. Altimetric data show that the symmetric inequality is violated in the low- and midlatitude ocean, again suggesting the potential impact of the “bottomness” of friction on eddies. Inequalities developed for multilayer turbulence suggest that high baroclinic modes in the mean shear also enhance small-scale baroclinic eddy energy. The inequalities motivate a new interpretation of barotropization in weakly damped turbulence. In that limit the barotropic mode dominates the spatial average of kinetic energy density because large values of barotropic density are found throughout the model domain, consistent with the barotropic cascade to large horizontal scales, while baroclinic density is spatially localized.
Gap-Leaping Western Boundary Current in a Circular Tank Model
Authors: Sheremet Vitalii A. , Kuehl Joseph
Published: June 2007

An oceanographically generic problem of the interaction of a boundary current with bathymetric features such as a gap in the ridge or a strait between two islands is considered. Multiple flow patterns (penetrating or leaping the gap) and hysteresis (dependence on prior evolution) may exist in such systems. Examples include the Gulf Stream leaping from the Yucatan to Florida and the Kuroshio leaping from Luzon to Taiwan. Using numerical analysis, Sheremet earlier found that multiple steady states can be explained by variation in the balance between the inertia (which promotes leaping state) and the β effect (which promotes penetrating state). In the present work a verification of the multiple states and hysteresis in a laboratory model are offered. To set up a gap-leaping current, a circular tank with a sloping bottom (simulating the β effect) is used, and the flow is driven using a new method of pumping fluid through sponges (thus generating a Sverdrup flow in the interior). A semicircular ridge with a gap is inserted into the western part of the tank. Using a dye release flow visualization method, the existence of multiple flow patterns over varying boundary current transport values differing by a factor of more than 2 are dramatically shown. An associated numerical model in bipolar curvilinear coordinates, which allows for the matching of all the boundaries, reproduces the laboratory results very well. This idealized problem offers a very useful geophysical test case for numerical models involving flow separation and reattachment.
The Importance of Tidal and Lateral Asymmetries in Stratification to Residual Circulation in Partially Mixed Estuaries*
Authors: Scully Malcolm E. , Friedrichs Carl T.
Published: June 2007

Measurements collected in the York River estuary, Virginia, demonstrate the important impact that tidal and lateral asymmetries in turbulent mixing have on the tidally averaged residual circulation. A reduction in turbulent mixing during the ebb phase of the tide caused by tidal straining of the axial density gradient results in increased vertical velocity shear throughout the water column during the ebb tide. In the absence of significant lateral differences in turbulent mixing, the enhanced ebb-directed transport caused by tidal straining is balanced by a reduction in the net seaward-directed barotropic pressure gradient, resulting in laterally uniform two-layer residual flow. However, the channel–shoal morphology of many drowned river valley estuaries often leads to lateral gradients in turbulent mixing. Tidal straining may then lead to tidal asymmetries in turbulent mixing near the deeper channel while the neighboring shoals remain relatively well mixed. As a result, the largest lateral asymmetries in turbulent mixing occur at the end of the ebb tide when the channel is significantly more stratified than the shoals. The reduced friction at the end of ebb delays the onset of the flood tide, increasing the duration of ebb in the channel. Conversely, over the shoal regions where stratification is more inhibited by tidal mixing, there is greater friction and the transition from ebb to flood occurs more rapidly. The resulting residual circulation is seaward over the channel and landward over the shoal. The shoal–channel segregation of this barotropically induced estuarine residual flow is opposite to that typically associated with baroclinic estuarine circulation over channel–shoal bathymetry.
Internal Tides in the Southwestern Atlantic off Brazil: Observations and Numerical Modeling
Authors: Pereira Adriene F. , Castro Belmiro M.
Published: June 2007

Data collected from moored instruments, deployed over the southeastern Brazilian continental shelf during the summer and winter months of 2001, show internal tide activity near the shelf break. To help to elucidate the observations, a fully three-dimensional nonlinear primitive equation model is applied to simulate the regional barotropic and baroclinic tides. Two semidiurnal (M2 and S2) and two diurnal (K1 and O1) tidal frequencies are considered. Tidal surface elevations are relatively small over the whole modeled area, reaching maximum values of about 0.40 m for M2 and 0.11 m for O1. Comparison between observed and computed tide elevation and Greenwich phase shows reasonable agreement. When the baroclinic response of the model is investigated, stratification is prescribed using summer and winter climatology data of potential density. In this case, the model response to summer and winter stratifications is very similar and internal tides are generated over the shelf break and slope, with vertical displacements up to 25 m, and seaward propagation. Modeled semidiurnal tidal ellipses agree well with winter and summer observations. Observed diurnal tidal ellipses in the middle of the continental shelf and close to the shelf break during summer show an intensification through the water column that could not be represented by the model. Estimates of the total baroclinic M2 offshore energy flux are about 3.5 and 0.5 MW considering winter and summer stratifications, respectively. Although these quantities are three orders of magnitude less than that estimated for regions known for intense internal tides, they refer to offshore fluxes computed for a very small section of the southeastern Brazilian shelf. This is the first published investigation into internal tides in the southwestern Atlantic Ocean off Brazil.
Distribution of Energy Spectra, Reynolds Stresses, Turbulence Production, and Dissipation in a Tidally Driven Bottom Boundary Layer
Authors: Luznik L. , Zhu W. , Gurka R. , Katz J. , Nimmo Smith W. A. M. , Osborn T. R.
Published: June 2007

Seven sets of 2D particle image velocimetry data obtained in the bottom boundary layer of the coastal ocean along the South Carolina and Georgia coast [at the South Atlantic Bight Synoptic Offshore Observational Network (SABSOON) site] are examined, covering the accelerating and decelerating phases of a single tidal cycle at several heights above the seabed. Additional datasets from a previous deployment are also included in the analysis. The mean velocity profiles are logarithmic, and the vertical distribution of Reynolds stresses normalized by the square of the free stream velocity collapse well for data obtained at the same elevation but at different phases of the tidal cycle. The magnitudes of 〈u′u′〉, 〈w′w′〉, and −〈u′w′〉 decrease with height above bottom in the 25–160-cm elevation range and are consistent with the magnitudes and trends observed in laboratory turbulent boundary layers. If a constant stress layer exists, it is located below 25-cm elevation. Two methods for estimating dissipation rate are compared. The first, a direct estimate, is based on the measured in-plane instantaneous velocity gradients. The second method is based on fitting the resolved part of the dissipation spectrum to the universal dissipation spectrum available in Gargett et al. Being undervalued, the direct estimates are a factor of 2–2.5 smaller than the spectrum-based estimates. Taylor microscale Reynolds numbers for the present analysis range from 24 to 665. Anisotropy is present at all resolved scales. At the transition between inertial and dissipation range the longitudinal spectra exhibit a flatter than −5/3 slope and form spectral bumps. Second-order statistics of the velocity gradients show a tendency toward isotropy with increasing Reynolds number. Dissipation exceeds production at all measurement heights, but the difference varies with elevation. Close to the bottom, the production is 40%–70% of the dissipation, but it decreases to 10%–30% for elevations greater than 80 cm.
Vortex Dipole Formation by Baroclinic Instability of Boundary Currents
Authors: Chérubin L. , Carton X. , Dritschel D. G.
Published: June 2007

In situ data of the Mediterranean Water undercurrents and eddies south of Portugal indicate that the undercurrents have a tubelike structure in potential vorticity and that dipole formation can occur when the lower undercurrent extends seaward below an offshore upper countercurrent. A two-layer quasigeostrophic model is used to determine the dynamical conditions under which dipole formation is possible. With piecewise-constant potential vorticity, the flow exhibits two linear modes of instability comparable to those found in the Phillips model with topography. Weakly nonlinear analysis and fully nonlinear simulations of the flow evolution agree on the regimes of either finite-amplitude perturbation saturation, corresponding to filamentation, or amplification, corresponding to vortex or dipole formation. This latter regime is more specifically studied: vortex dipole formation and ejection from the coast is obtained for long waves, with opposite-signed but similar amplitude layer potential vorticities. A simple point vortex model reproduces this phenomenon under the same conditions. It is then shown that dipole formation occurs for minimal wave dispersion, and hence for weak horizontal velocity shears. As observed at sea, dipoles are formed when the lower potential vorticity core extends seaward below a countercurrent.
Dynamical Tropical Cyclone 96- and 120-h Track Forecast Errors in the Western North Pacific
Authors: Kehoe Ryan M. , Boothe Mark A. , Elsberry Russell L.
Published: June 2007

The Joint Typhoon Warning Center has been issuing 96- and 120-h track forecasts since May 2003. It uses four dynamical models that provide guidance at these forecast intervals and relies heavily on a consensus of these four models in producing the official forecast. Whereas each of the models has skill, each occasionally has large errors. The objective of this study is to provide a characterization of these errors in the western North Pacific during 2004 for two of the four models: the Navy Operational Global Atmospheric Prediction System (NOGAPS) and the U.S. Navy’s version of the Geophysical Fluid Dynamics Laboratory model (GFDN). All 96- and 120-h track errors greater than 400 and 500 n mi, respectively, are examined following the approach developed recently by Carr and Elsberry. All of these large-error cases can be attributed to the models not properly representing the physical processes known to control tropical cyclone motion, which were classified in a series of conceptual models by Carr and Elsberry for either tropical-related or midlatitude-related mechanisms. For those large-error cases where an error mechanism could be established, midlatitude influences caused 83% (85%) of the NOGAPS (GFDN) errors. The most common tropical influence is an excessive direct cyclone interaction in which the tropical cyclone track is erroneously affected by an adjacent cyclone. The most common midlatitude-related errors in the NOGAPS tracks arise from an erroneous prediction of the environmental flow dominated by a ridge in the midlatitudes. Errors in the GFDN tracks are caused by both ridge-dominated and trough-dominated environmental flows in the midlatitudes. Case studies illustrating the key error mechanisms are provided. An ability to confidently identify these error mechanisms and thereby eliminate likely erroneous tracks from the consensus would improve the accuracy of 96- and 120-h track forecasts.
The New French Operational Radar Rainfall Product. Part II: Validation
Authors: Tabary P. , Desplats J. , Do Khac K. , Eideliman F. , Gueguen C. , Heinrich J-C.
Published: June 2007

A new operational radar-based rainfall product has been developed at Météo-France and is currently being deployed within the French operational network. The new quantitative precipitation estimation (QPE) product is based entirely on radar data and includes a series of modules aimed at correcting for ground clutter, partial beam blocking, and vertical profile of reflectivity (VPR) effects, as well as the nonsimultaneity of radar measurements. The surface rainfall estimation is computed as a weighted mean of the corrected tilts. In addition to the final QPE, a map of quality indexes is systematically generated. This paper is devoted to the validation of the new radar QPE. The VPR identification module has been specifically validated by analyzing 489 precipitation events observed over 1 yr by a representative eight-radar subset of the network. The conceptual model of VPR used in the QPE processing chain is shown to be relevant. A climatology of the three shape parameters of the conceptual VPR (brightband peak, brightband thickness, and upper-level decreasing rate) is established and the radar-derived freezing-level heights are shown to be in good agreement with radiosonde data. A total of 27 precipitation events observed by three S-band radars of the network during the winter of 2005 and the autumns of 2002 and 2003 are used to compare the new radar QPE to the old one. Results are stratified according to the distance to the radar and according to the height of the freezing level. The Nash criterion is increased from 0.23 to 0.62 at close range (below 50 km) and from 0.35 to 0.42 at long range (between 100 and 150 km). The relevance of the proposed quality indexes is assessed by examining their statistical relationship with long-term radar–rain gauge statistics. Mosaics of QPE and quality indexes are also illustrated.
Forecasting the Maintenance of Quasi-Linear Mesoscale Convective Systems
Authors: Coniglio Michael C. , Brooks Harold E. , Weiss Steven J. , Corfidi Stephen F.
Published: June 2007

The problem of forecasting the maintenance of mesoscale convective systems (MCSs) is investigated through an examination of observed proximity soundings. Furthermore, environmental variables that are statistically different between mature and weakening MCSs are input into a logistic regression procedure to develop probabilistic guidance on MCS maintenance, focusing on warm-season quasi-linear systems that persist for several hours. Between the mature and weakening MCSs, shear vector magnitudes over very deep layers are the best discriminators among hundreds of kinematic and thermodynamic variables. An analysis of the shear profiles reveals that the shear component perpendicular to MCS motion (usually parallel to the leading line) accounts for much of this difference in low levels and the shear component parallel to MCS motion accounts for much of this difference in mid- to upper levels. The lapse rates over a significant portion of the convective cloud layer, the convective available potential energy, and the deep-layer mean wind speed are also very good discriminators and collectively provide a high level of discrimination between the mature and dissipation soundings as revealed by linear discriminant analysis. Probabilistic equations developed from these variables used with short-term numerical model output show utility in forecasting the transition of an MCS with a solid line of 50+ dBZ echoes to a more disorganized system with unsteady changes in structure and propagation. This study shows that empirical forecast tools based on environmental relationships still have the potential to provide forecasters with improved information on the qualitative characteristics of MCS structure and longevity. This is especially important since the current and near-term value added by explicit numerical forecasts of convection is still uncertain.
The Use of a Vortex Insertion Technique to Simulate the Extratropical Transition of Hurricane Michael (2000)
Authors: Fogarty Christopher T. , Greatbatch Richard J. , Ritchie Harold
Published: June 2007

On 19 October 2000, Hurricane Michael merged with an approaching baroclinic trough over the western North Atlantic Ocean south of Nova Scotia. As the hurricane moved over cooler sea surface temperatures (SSTs; less than 25°C), it intensified to category-2 intensity on the Saffir–Simpson hurricane scale [maximum sustained wind speeds of 44 m s−1 (85 kt)] while tapping energy from the baroclinic environment. The large “hybrid” storm made landfall on the south coast of Newfoundland with maximum sustained winds of 39 m s−1 (75 kt) causing moderate damage to coastal communities east of landfall. Hurricane Michael presented significant challenges to weather forecasters. The fundamental issue was determining which of two cyclones (a newly formed baroclinic low south of Nova Scotia or the hurricane) would become the dominant circulation center during the early stages of the extratropical transition (ET) process. Second, it was difficult to predict the intensity of the storm at landfall owing to competing factors: 1) decreasing SSTs conducive to weakening and 2) the approaching negatively tilted upper-level trough, favoring intensification. Numerical hindcast simulations using the limited-area Mesoscale Compressible Community model with synthetic vortex insertion (cyclone bogus) prior to the ET of Hurricane Michael led to a more realistic evolution of wind and pressure compared to running the model without vortex insertion. Specifically, the mesoscale model correctly simulates the hurricane as the dominant circulation center early in the transition process, versus the baroclinic low to its north, which was the favored development in the runs not employing vortex insertion. A suite of experiments is conducted to establish the sensitivity of the ET to various initial conditions, lateral driving fields, domain sizes, and model parameters. The resulting storm tracks and intensities fall within the range of the operational guidance, lending support to the possibility of improving numerical forecasts using synthetic vortex insertion prior to ET in such a model.
Operational Evaluation of a Selective Consensus in the Western North Pacific Basin
Authors: Sampson Charles R. , Knaff John A. , Fukada Edward M.
Published: June 2007

The Systematic Approach Forecast Aid (SAFA) has been in use at the Joint Typhoon Warning Center since the 2000 western North Pacific season. SAFA is a system designed for determination of erroneous 72-h track forecasts through identification of predefined error mechanisms associated with numerical weather prediction models. A metric for the process is a selective consensus in which model guidance suspected to have 72-h error greater than 300 n mi (1 n mi = 1.85 km) is first eliminated prior to calculating the average of the remaining model tracks. The resultant selective consensus should then provide improved forecasts over the nonselective consensus. In the 5 yr since its introduction into JTWC operations, forecasters have been unable to produce a selective consensus that provides consistent improved guidance over the nonselective consensus. Also, the rate at which forecasters exercised the selective consensus option dropped from approximately 45% of all forecasts in 2000 to 3% in 2004.
Increasing the Reliability of Reliability Diagrams
Authors: Bröcker Jochen , Smith Leonard A.
Published: June 2007

The reliability diagram is a common diagnostic graph used to summarize and evaluate probabilistic forecasts. Its strengths lie in the ease with which it is produced and the transparency of its definition. While visually appealing, major long-noted shortcomings lie in the difficulty of interpreting the graph visually; for the most part, ambiguities arise from variations in the distributions of forecast probabilities and from various binning procedures. A resampling method for assigning consistency bars to the observed frequencies is introduced that allows for immediate visual evaluation as to just how likely the observed relative frequencies are under the assumption that the predicted probabilities are reliable. Further, an alternative presentation of the same information on probability paper eases quantitative evaluation and comparison. Both presentations can easily be employed for any method of binning.
Just Whose Side Is Time On?
Authors: Hathaway Robert M.
Published: June 2007

President Bush's bold National Security Strategy document of September 2002 would appear to have been written with North Korea as much as Iraq in mind. Yet the Bush administration has been uncharacteristically passive in responding to the challenge posed by Pyongyang's nuclear weapons ambitions, especially in comparison with the forceful manner with which the administration dealt with Iraq. In the latter case, Bush mobilized the full weight of military force; seemed disdainful of allies, international institutions and multilateral diplomacy; and moved forward with what his critics deemed reckless abandon. In the case of North Korea, on the other hand, the President has emphasized patience, close coordination with allies and an overall lack of urgency oddly at variance with his `axis of evil' characterization of the regime in Pyongyang, and with dangerous advances in North Korea's nuclear arsenal. This essay attempts to explain the rationale behind the Bush administration's surprisingly relaxed approach to the North Korea challenge.
Caught between Alliance and Brotherhood
Authors: Kim Tae-hyo
Published: June 2007

A cost—benefit analysis leads to the conclusion that South Korea's search for non-violent responses to the North Korean nuclear issue causes a dilemma for Seoul. It must balance its security policies toward Washington and Pyongyang, and that dilemma can be resolved only when the North Korean nuclear problem, the most critical and the most difficult hurdle, is resolved. In analyzing critical variables that will determine the success or failure of the six-party talks multilateral approach, this article challenges the central tenet of cooperation theories: if a sufficient number of countries collaborate, they can achieve preventive diplomacy. Cooperation to dismantle the North Korean nuclear program will be difficult due to backsliding (`sanction busting') by concerned countries.
Integration of Vision and Inertial Sensors for 3D Arm Motion Tracking in Home-based Rehabilitation
Authors: Tao Yaqin , Hu Huosheng , Zhou Huiyu
Published: June 2007

The integration of visual and inertial sensors for human motion tracking has attracted significant attention recently, due to its robust performance and wide potential application. This paper introduces a real-time hybrid solution to articulated 3D arm motion tracking for home-based rehabilitation by combining visual and inertial sensors. Data fusion is a key issue in this hybrid system and two different data fusion methods are proposed. The first is a deterministic method based on arm structure and geometry information, which is suitable for simple rehabilitation motions. The second is a probabilistic method based on an Extended Kalman Filter (EKF) in which data from two sensors is fused in a predict-correct manner in order to deal with sensor noise and model inaccuracy. Experimental results are presented and compared with commercial marker-based systems, CODA and Qualysis. They show good performance for the proposed solution.
An Introduction to Inertial and Visual Sensing
Authors: Corke Peter , Lobo Jorge , Dias Jorge
Published: June 2007

In this paper we present a tutorial introduction to two important senses for biological and robotic systems — inertial and visual perception. We discuss the fundamentals of these two sensing modalities from a biological and an engineering perspective. Digital camera chips and micro-machined accelerometers and gyroscopes are now commodities, and when combined with today's available computing can provide robust estimates of self-motion as well 3D scene structure, without external infrastructure. We discuss the complementarity of these sensors, describe some fundamental approaches to fusing their outputs and survey the field.
Modernization of Library and Information Services in Higher Education in Swaziland: strategic interventions, 2000/1—2005/6
Authors: Muswazi Paiki , Yumba Dickson
Published: June 2007

This is a discussion of the implementation of the University of Swaziland (UNISWA) strategic plan 2000/1—2005/6. The goal of the article is to assess the impact of the information technology, policies and procedures, collaboration, funding, management, human resources development, preservation, marketing and information service delivery strategies on the modernization of its library and information services (LIS). It is argued that UNISWA has effected considerable staff re-skilling and made some progress towards widening access to quality subscription based electronic resources and optimizing the utilization of open access materials. Implementation was negatively influenced by low funding, limited local content on the web, inadequate information and communication technology infrastructure, scarce professional skills, and restrictive policies and procedures. It concludes that further work revolving around the above factors, taking into account user needs for independent life long learning, is the key to deepening the modernization of LIS at UNISWA.
Special Section: Where to look? Supervising Group Analysis — A Relations Disorder Perspective
Authors: Friedman Robi
Published: June 2007

Thinking in interpersonal terms rather than intra-psychic processes may not be easy. A further move in this direction seems cardinal in the development of conductors of group therapy. Handling questions of the optimal therapeutic environment for patients encounters great difficulties because of the lamentable scarcity of indications for group therapy. The unsatisfactory situation of indications is also true for individual psychotherapy. This article focuses on some of the most common problems encountered while supervising group therapy, related to the therapist's difficulty in handling the relations patterns and their influence.
Special Section: Internal and External Boundaries of Supervision
Authors: Gregurek Rudolf
Published: June 2007

This article proposes that supervision is an essential element of psychotherapy education and explains the relationship between internal and external boundaries of supervision. It is important that the boundary between the supervisory and the therapeutic relationship is clear. Each supervisor-supervisee negotiates the intimacy and content of the supervision according to their style and needs; there are clear differences between the tasks of the two relationships. It is important to understand any controversy as to the degree to which the supervision should serve as an exploration of the supervisee's countertransference (internal boundaries) versus conflict inherent in the roles of supervisor in institutes where the supervisor is also the superior or older colleague of the supervisee (external boundaries).
Special Section: Group Supervision of Group Psychotherapy with Psychotic Patients: A Group-Analytic Approach
Authors: Urlić Ivan , Britvić Dolores
Published: June 2007

In this article the authors document their experiences in small and median groups of supervision of conductors and therapeutic teams who are engaged in group psychotherapy with psychotic patients within different institutional frameworks, and discuss dynamics, as well as the enlarging of therapeutic possibilities of group psychotherapy of group-analytic orientation for application in these settings. They propose the possibility that at times the group itself can become the supervisor, i.e. that the supervision might be effectuated by the group, under guidance of an experienced conductor.
Theoretical and Conceptual Notes Concerning Transference and Countertransference Processes in Groups and by Groups, and the Social Unconscious: Part III
Authors: Hopper Earl
Published: June 2007

In this article, I will define my concept of the social unconscious and specify several aspects of it, and compare this concept with the Jungian concept of the collective unconscious. I will focus on the constraints and restraints of the social unconscious on transference and countertransference processes by persons in groups (Part I, December, 2006) and by groups of persons (Part II, March, 2007). I will also discuss continuing resistance to the use of the `social unconscious' in clinical work.
Envisioning Nursing in 2050 Through the Eyes of Nurse Theorists: Katie Eriksson and Margaret Newman
Authors: Pilkington F. Beryl
Published: June 2007

Nurse theorists Katie Eriksson and Margaret Newman envision how their theoretical ideas will be expressed in the world in 2050. Eriksson believes that the fundamental concepts of health and suffering in her theory of caritative caring will endure, but will find newer and richer forms of expression. By giving voice to the caring ethos in symbolic form, we can shape the mysterious and unpredictable future. Newman speaks of an emerging pattern of nursing knowledge that reflects compassion, transformation, and freedom. She believes that individual nurses who focus on clients' unitary, evolving pattern of the whole will help to transform the health of society.
Your Magical, Mystical Ways Part II: A Community Forum on Quality of Life
Authors: Bunkers Sandra Schmidt
Published: June 2007

This column presents the proceedings of a community forum for nursing sponsored by South Dakota State University College of Nursing in Sioux Falls, South Dakota. The community forum was entitled Quality of Life & Healthcare Today and featured Dr. Rosemarie Rizzo Parse as the keynote speaker. Several panelists presented papers on quality of life including the following: “Quality of Life Issues for Returning Iraq Veterans,” “Quality of Life Issues in the Student Experience,” “Quality of Life Issues in an Acute Health Crisis,” and “Quality of Life Issues in Nursing Leadership.” Dr. Parse responded to each panelist's presentation with insights that expanded understanding of quality of life and human becoming.
Nursing, Healthcare, and Culture: A View of the Year 2050 From Germany and the United Kingdom
Authors: Fawcett Jacqueline , Bekel Gerd , Biley Francis C. , Fragemann Kirstin
Published: June 2007

This column presents a dialogue with German nurse scholar Gerd Bekel and United Kingdom nurse scholars, Francis C. Biley and Kirstin Fragemann, who share their respective visions and understanding of each country's vision of nursing, healthcare, and quality of life in the year 2050.
Coping Processes of Taiwanese Families During the Postdischarge Period for an Elderly Family Member With Hip Fracture
Authors: Li Hsiao-Juan , Shyu Yea-Ing Lotus
Published: June 2007

The purposes of this study were to develop a conceptual framework explaining the coping processes of Taiwanese families after hospital discharge of an elderly family member with hip fracture and to use the Roy adaptation model to examine their interdependence relationships. In-depth, face-to-face interviews were tape-recorded and transcribed verbatim. Data were analyzed by grounded theory method. Findings revealed that a harmony between receiving and giving relationships was maintained by care receivers and caregivers during the postdischarge period to achieve an outcome of adaptation in their relationships. By understanding these coping processes, nurses can assist families to enhance adaptation.
Forms of Positioning in the Dialogical Self
Authors: Raggatt Peter T.F.
Published: June 2007

Notions of a `dialogical self' are finding application across many areas of psychology and beyond into neighbouring social sciences disciplines. This breadth, however, creates problems of overall coherence. When authors refer to a `dialogical self', they are not always talking about the same thing. In this paper I address this problem by considering theories of positioning . I argue that dialogical theory and positioning theory are closely inter-linked, and that forms of positioning which bear on the dialogical self can be classified. A system is outlined which organizes forms of positioning by mode of expression (e.g. discursive, performed, embodied), sources of dynamic conflict (e.g. moral career, agency, communion) and cultural and social constructions (e.g. roles, power hierarchies). The paper discusses the classificatory system and illustrates different forms of positioning in the life of the Australian actor and comic satirist Barry Humphries.
Sex Differences, Evolutionary Psychology and Biosocial Theory
Authors: Luxen Marc F.
Published: June 2007

Biosocial theory claims that evolution did not design human psychological sex differences. It argues that these are the result of the allocation of men and women into different sex roles, based on physical differences. This article argues, however, that biosocial theory is not an alternative to evolutionary psychology in the explanation of human psychological sex differences. Specifically, biosocial theory is incompatible with evolutionary reasoning and it ignores findings of hormonal psychology, developmental psychology and comparative psychology. Moreover, by posing the need for special explanations, it violates the principle of Occam's razor. Finally, it does not provide an explanation as to why sex differences in human partner choice are finely tuned to fitness.
A Life of Variable Speeds
Authors: Mølbak Rune L.
Published: June 2007

In this paper, I attempt to explicate the fundamental ontology of the French philosopher Gilles Deleuze in order to think through the implications of his understanding of the logic of sense for a critique and reconstruction of the ethics and practice of contemporary psychotherapy. I shall argue that Deleuze's understanding of sense leads to a new intensive conceptualization of subjectivity, which radically deconstructs the common sense and good sense that has structured Western notions of the subject since Plato. This new understanding of subjectivity opens up the possibility of constructing a different psychotherapy: a psychotherapy of difference conceptualized in terms of an ontology of dual temporalities or variable speeds.
The culpability of accounting in perpetuating the Holocaust
Authors: Lippman Ellen J. , Wilson Paula A.
Published: June 2007

The Holocaust was an event unprecedented in the history of man. Never before had a people been systematically and deliberately hunted and gathered, from many different countries, by one country for the sole purpose to annihilate a people. This article considers the Holocaust, specifically slave labor operations managed by German corporations and Nazi state run entities, and identifies accounting information and common financial analyses used to assist management in operation of these facilities. The article reviews the role of accountants and the information they prepared in perpetrating the injustices experienced by concentration camp victims during the Holocaust. The history of the German accounting profession and the changes to the profession during the war years are considered as a means to explain accountant behavior. Finally, the culpability of accountants for the Holocaust is considered, using slave trading literature as well as the standard of responsibility introduced during the International Military Tribunals.
Seeing and hearing music teaching and learning: Transforming classroom observations through ethnography and portraiture
Authors: Miranda Martina L. , Robbins Janet , Stauffer Sandra L.
Published: June 2007

The purpose of this study was to engage preservice teachers in thoughtful examination of teaching and learning in music classrooms through application of ethnographic and portraiture techniques, and to ascertain the efficacy of this approach in undergraduate music teacher preparation courses. Participants included faculty members at three universities and the preservice students enrolled in elementary general music methods courses. Students were coached in ethnographic data collection techniques (e.g., observations and field notes, memos, peer debrief, collection of artefacts) by their respective professors. Schwab's (1973) four curriculum commonplaces served as frames for students' observations in music classrooms. Students constructed ethnography-portraiture projects based on their data records and participated in exit interviews at the end of the semester. Data, comprised of students' projects and interviews, were analysed by the faculty participants for evidence of preservice teachers' ability to engage in the ethnography process, their thoughtful critique of the culture of the music classrooms and the teachers and children they observed, and changes in preservice teachers' perceptions and thinking about music teaching and learning. Analysis indicated that ethnographic techniques enabled the preservice teachers to articulate a multi-layered picture of teaching and learning in elementary music classrooms, to engage in nuanced reflections about their identity as teachers, and to provide detailed descriptions that were both analytical and critical as supported by data and informed by connections made with material from their methods coursework. Additional findings include evidence of insightful learning characterised by clarification of career goals, appreciation of the unexpected, changes in perspective, and emerging teacher identities.
Children's perspectives of participation in music youth arts settings: Meaning, value and participation
Authors: Barrett Margaret S. , Smigiel Heather M.
Published: June 2007

This paper presents an analysis of music specific data generated in a national collective case study of Australian children's perceptions of the meaning and value of the arts in their lives and their descriptions of the nature and extent of their participation. Specifically, the paper reports on children's (aged 6-17 years) perceptions of this phenomenon in relation to their participation in four music youth arts sites. i Data were generated through individual artefact-elicited interviews with 25 participants across these sites. A thematic analysis of these data was undertaken and five key factors emerged concerning children's perceptions of participation in music youth arts settings. Children attribute participation in these settings to: a love of performance; a shared unity of purpose; a desire for challenge and `professionalism'; the quality of relationships developed and sustained in these settings; and, the opportunities for individual growth and well-being that arise in these settings. Consideration is given to the implications that these five factors hold for music education in school settings.
The influence of teachers' backgrounds on their perceptions of musical creativity: A qualitative study with secondary school music teachers
Authors: Odena Oscar , Welch Graham F.
Published: June 2007

This paper examines the relationship between six secondary school teachers' backgrounds and their perceptions of musical creativity. A unit of work involving composition and improvisation activities with pupils aged 11-14 was videotaped for each teacher. Participants were invited to comment on the videotapes during interviews, which were subsequently analysed using content analysis with the assistance of the computer programme NVivo. Teachers were also asked to reflect on specific instances that had shaped the direction of their musical outlook by completing a Musical Career Path questionnaire. It was observed that their experiences fell into three strands, namely musical, teacher-education, and professional teaching. The influence of these strands on the teachers' thinking is discussed in four sections that refer to a four-fold framework outlined from the literature review: their perceptions of (a) creative pupils, (b) an environment that fosters creativity, (c) the creative process, and (d) creative musical products. Data analyses indicate that the most influential strand is `musical'. Participants with composing experience and practical knowledge of different music styles were more articulate at describing the environment for creativity and how this might be assessed in pupils' work. Educational implications based on these findings are considered in the conclusion.