Ocean waves and turbulence as observed with an adaptive coherent multifrequency radar

An adaptive coherent multifrequency radar system is developed for several applications. The velocity distribution (Doppler spectrum) and spectral intensity of 15 different irregularity scales (waves and turbulence) can be measured simultaneously. Changing the azimuth angle of the antennas at regular intervals, the directivity of the wave/turbulence pattern on the sea surface can also be studied. A series of measurements for different air/sea conditions are carried out from a coast based platform. Experiments in the Atlantic are also performed with the same equipment making use of the NASA Electra aircraft. The multifrequency radar allows the measurement of the velocity distribution (""coherent and incoherent component'') associated with 15 different ocean irregularity scales simultaneously in a directional manner. It is possible to study the different air/sea mechanisms in some degree of detail

Critical Illness Polyneuropathy, Complications

Background and Purpose: Critical Illness Polyneuropathy/Myopathy results from the presence of sepsis, multi-organ or respiratory failure, septic inflammatory response syndrome, or difficulty weaning from the ventilator. Decreased amplitudes of compound muscle and sensory action potentials, and widespread denervation potentials in muscle are the primary cause for the resultant muscle weakness. The purpose of this paper is to report on the rehabilitation progress in a woman who developed CIP following surgical complications. Case Description: A 63-year-old woman suffered from critical illness polyneuropathy following a complicated recovery following a sigmoidectomy secondary to diverticular disease. Multiple surgeries, inability to wean from the ventilator, and co-morbidities of obesity and smoking complicated her rehabilitation. Physical therapy rehabilitation included general strengthening, gait, balance and proprioceptive training, and activity modification education. Outcome: The patient returned home with assistance from family in three weeks. She was discharged with a single point cane and education on activity modification. Improvement, manifested in her AM-PAC and Tinetti functional outcome assessments, supported her discharge home. Discussion: Following three weeks of intensive physical therapy, the patient was ready for discharge and given the tools to further her rehabilitation to be functionally independent. She returned home with an assistive device and required minimal assistance from her family. Conclusion: Aggressive physical therapy that targets lower extremity and trunk strengthening, as well as balance and proprioception, and activity modification, is effective treatment for critical illness polyneuropathy

Superintendent Selection in North Dakota: Practices and Criteria

The purpose of this study was to learn how North Dakota school board members who had recendy participated in the selection of a school superintendent perceived the relative importance of (a) hiring practices, (b) administrative skills, and (c) superintendent attributes. Analyses of individual items and clusters of items were conducted. In addition to the general purpose, analyses were conducted by gender, by duration of board incumbency, and by school enrollment size. Data for the study consisted of responses from 124 school board members from 39 school districts. (The universe of districts which had hired a superintendent during the 1990-1993 time frame was 55 districts.) Responses were gathered from a three-part questionnaire constructed by the writer. Administrative skills assessments dominated the selection process for new superintendents. Board members placed more importance on personal attributes of candidates than on hiring practices used. Female board members generally recorded higher importance assessments than male board members. Female board members also preferred greater education, experience, and management skill. Board incumbency seemed to be a negligible variable in the selection of a new superintendent. In the selection process, board members from smaller schools valued the advice of others less than did board members from larger schools. Board members from large schools were less concerned about age, appearance, and current job location than were board members from smaller schools

Economy of Means in Ravel's Sonatine

Maurice Ravel&rsquo;s Sonatine is a strikingly brief and internally cohesive musical achievement. A Schoenberg-style motivic analysis reveals that this cohesiveness is achieved through an economical treatment of only a few short motives. This thesis analyzes the work and its component motives, from the motives that make up the basic idea of the first theme, to the myriad appearances and transformations of these motives throughout the rest of the piece. This analysis is in turn used to make suggestions about how the revealed connections translate into performance suggestions, from the puzzling rest that begins the piece, to motivic linkages between the beginnings and endings of each movement.</p

Skill-Acquisition Research and Piano Study: What a Cross-Disciplinary Approach Can Teach Us About Increasing the Use of Memory-Enhancing Techniques

Skill-acquisition and expertise research have revealed a wealth of information about the processes students use to gain expertise in a wide variety of fields, including music. Some of the most interesting theories to come out of this field of research are psychological- and cognitive-science-based descriptions of superior expert memory. This project examines some of the most prominent of these theories and suggests ways in which piano teachers can use their findings to teach in a way that maximizes the potential for growth in the memory skills of their students.</p

Modeling of unsaturated granular materials in flexible pavements

The unsaturated granular material (UGM) is found to exhibit the moisture-sensitive and stress-dependent nonlinear cross-anisotropic behaviour in flexible pavements. This paper aims at developing a finite element (FE) model for pavement structure, which takes into account this behaviour of UGM. First, the Lytton model is employed to characterize the moisture-sensitive and stress-dependent behaviour of UGM, which incorporated a matric suction term to the existing stress-dependent constitutive model. The Lytton model is validated by the laboratory resilient modulus tests on the selected UGMs at different moisture contents. Second, the nonlinear cross-anisotropic constitutive equation of UGM is derived from the generalized Hooke's Law. The coefficients of the constitutive model are determined by the rapid triaxial test. Third, a User-Defined Material (UMAT) subroutine is developed to characterize this constitutive behaviour in the FE software ABAQUS. The UMAT subroutine adopts the secant stiffness approach with multiple damping factors. The UMAT subroutine is then implemented in the FE model of flexible pavement structures. The FE simulation results indicate the nonlinear cross-anisotropic model predicts greater pavement responses than the isotropic model. When the UGM is suction sensitive, it is found that the moisture content of UGM significantly affects the moduli distribution of base layer and the critical strains (i.e., tensile strain at the bottom of asphalt concrete, and compressive strains in base and subgrade layers) of pavement structures

On dual Schur domain decomposition method for linear first-order transient problems

This paper addresses some numerical and theoretical aspects of dual Schur domain decomposition methods for linear first-order transient partial differential equations. In this work, we consider the trapezoidal family of schemes for integrating the ordinary differential equations (ODEs) for each subdomain and present four different coupling methods, corresponding to different algebraic constraints, for enforcing kinematic continuity on the interface between the subdomains. Method 1 (d-continuity) is based on the conventional approach using continuity of the primary variable and we show that this method is unstable for a lot of commonly used time integrators including the mid-point rule. To alleviate this difficulty, we propose a new Method 2 (Modified d-continuity) and prove its stability for coupling all time integrators in the trapezoidal family (except the forward Euler). Method 3 (v-continuity) is based on enforcing the continuity of the time derivative of the primary variable. However, this constraint introduces a drift in the primary variable on the interface. We present Method 4 (Baumgarte stabilized) which uses Baumgarte stabilization to limit this drift and we derive bounds for the stabilization parameter to ensure stability. Our stability analysis is based on the ``energy'' method, and one of the main contributions of this paper is the extension of the energy method (which was previously introduced in the context of numerical methods for ODEs) to assess the stability of numerical formulations for index-2 differential-algebraic equations (DAEs).Comment: 22 Figures, 49 pages (double spacing using amsart