1,996 research outputs found
On Sampling of stationary increment processes
Under a complex technical condition, similar to such used in extreme value
theory, we find the rate q(\epsilon)^{-1} at which a stochastic process with
stationary increments \xi should be sampled, for the sampled process
\xi(\lfloor\cdot /q(\epsilon)\rfloor q(\epsilon)) to deviate from \xi by at
most \epsilon, with a given probability, asymptotically as \epsilon
\downarrow0. The canonical application is to discretization errors in computer
simulation of stochastic processes.Comment: Published at http://dx.doi.org/10.1214/105051604000000468 in the
Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute
of Mathematical Statistics (http://www.imstat.org
On overload in a storage model, with a self-similar and infinitely divisible input
Let {X(t)}_{t\ge0} be a locally bounded and infinitely divisible stochastic
process, with no Gaussian component, that is self-similar with index H>0.
Pick constants \gamma >H and c>0. Let \nu be the L\'evy measure on
R^{[0,\infty)} of X, and suppose that R(u)\equiv\nu({y\inR^{[0,\infty)}:supt\ge
0y(t)/(1+ct^{\gamma})>u}) is suitably ``heavy tailed'' as u\to\infty (e.g.,
subexponential with positive decrease). For the ``storage process'' Y(t)\equiv
sup_{s\ge t}(X(s)-X(t)-c(s-t)^{\gamma}), we show that
P{sup_{s\in[0,t(u)]}Y(s)>u}\sim P{Y(\hat t(u))>u} as u\to\infty, when 0\le \hat
t(u)\le t(u) do not grow too fast with u [e.g., t(u)=o(u^{1/\gamma})]
Design, performance evaluation, and investigation of the theoretical capabilities of the NASA Millimeter-wave Imaging Radiometer (MIR)
The development of techniques for passive microwave retrieval of water vapor and precipitation parameters using millimeter- and sub-millimeter wavelength channels is reviewed. Channels of particular interest are in the tropospheric transmission windows at 90, 150, 220, and 340 GHz and centered around the water vapor lines at 183 and 325 GHz. Collectively, these channels have potential application in high-resolution mapping (e.g., from geosynchronous orbit), remote sensing of cloud and precipitation parameters, and retrieval of water vapor profiles. Both theoretical and experimental results to date are discussed
Functional outcome of patients undergoing open rotator cuff repair
Background: Rotator cuff tears are a common source of shoulder pain. The incidence of rotator cuff damage increases with age and is most frequently due to degeneration of the tendon rather than injury from sports or trauma. Rotator cuff tear can be treated arthroscopically, arthroscopically assisted (mini-open) or by an open procedure. Because of the technical demands of arthroscopic repair many surgeons consider open repair for the treatment of rotator cuff tears. This study was done to evaluate the functional outcome of shoulder after open rotator cuff repair.Methods: 26 patients with partial and complete rotator cuff tears underwent open rotator cuff repair and acromioplasty. Cases were followed up at 3 months and 6 months intervals and shoulder function was assessed using Constant-Murley scoring system and compared with the preoperative scores and analyzed using SPSS software.Results: Mean preoperative constant score was 33.95±7.545 while the mean constant score at 6 months post-surgery was 79.83±8.51 which was highly significant according to paired t test. The difference between preoperative, 3 months and 6 months constant scores of complete and partial tear patients was found to be statistically significant.Conclusions: There was highly significant increase in Constant-Murley score after 6 months in patients treated by open rotator cuff repair. Open repair still stands as an effective treatment for rotator cuff tears and doing acromioplasty during the procedure adds to better outcome after surgery
Exploration of Health Care Needs Among Sudanese Refugee Women
Many Sudanese refugees that have resettled in the United States have experienced severe trauma and loss during their migration, as well as physical, social, and psychological struggles in their continued adaptation to living in a new country. This study explored the healthcare needs of Sudanese women as they transition to living in the United States. Community-Based Collaborative Action Research (CBCAR) provided a framework for the study.
Qualitative descriptive design using focus groups was utilized to explore the healthcare needs of Sudanese Women. Eighteen women participated in the study, which consisted of five educational sessions that were immediately followed by five audio-taped focus groups. The educational seminars presented topics such as parenting skills, preventative health practices, childhood illnesses, and emotional well-being. Focus groups allowed for a confidential setting in which women were able to reflect on the information presented, as well as verbalize topics that they would like to receive more education on in the future.
Three themes were identified that reflected experience of Sudanese women. These included being pulled between two worldviews in ways of parenting and communicating with children, multiple difficulties maneuvering within the US health care system, and internal struggles in meeting emotional needs in their transition to living in the United States. This study may contribute to the empowerment of Sudanese women by providing them with a greater understanding and ability to maneuver within the US healthcare system. This partnering interchange may also increase nursing knowledge in offering culturally competent care to the Sudanese community and other refugee populations that have resettled in the United States.University of Kansas School of Nursing. Bachelor of Science in Nursing Honors Progra
Investigation of passive atmospheric sounding using millimeter and submillimeter wavelength channels
Activities within the period from July 1, 1992 through December 31, 1992 by Georgia Tech researchers in millimeter and submillimeter wavelength tropospheric remote sensing have been centered around the calibration of the Millimeter-wave Imaging Radiometer (MIR), preliminary flight data analysis, and preparation for TOGA/COARE. The MIR instrument is a joint project between NASA/GSFC and Georgia Tech. In the current configuration, the MIR has channels at 90, 150, 183(+/-1,3,7), and 220 GHz. Provisions for three additional channels at 325(+/-1,3) and 8 GHz have been made, and a 325-GHz receiver is currently being built by the ZAX Millimeter Wave Corporation for use in the MIR. Past Georgia Tech contributions to the MIR and its related scientific uses have included basic system design studies, performance analyses, and circuit and radiometric load design, in-flight software, and post-flight data display software. The combination of the above millimeter wave and submillimeter wave channels aboard a single well-calibrated instrument will provide unique radiometric data for radiative transfer and cloud and water vapor retrieval studies. A paper by the PI discussing the potential benefits of passive millimeter and submillimeter wave observations for cloud, water vapor and precipitation measurements has recently been published, and is included as an appendix
Investigation of passive atmospheric sounding using millimeter and submillimeter wavelength channels
Activities within the period from January 1, 1992 through June 30, 1992 by Georgia Tech researchers in millimeter and submillimeter wavelength tropospheric remote sensing have been centered around the integration and initial data flights of the MIR on board the NASA ER-2. Georgia Tech contributions during this period include completion of the MIR flight software and implementation of a 'quick-view' graphics program for ground based calibration and analysis of the MIR imagery. In the current configuration, the MIR has channels at 90, 150, 183 +/- 1,3,7, and 220 GHz. Provisions for three additional channels at 325 +/-1,3 and 9 GHZ have been made, and a 325-GHz receiver is currently being built by the ZAX Millimeter Wave Corporation for use in the MIR. The combination of the millimeter wave and submillimeter wave channels aboard a single well-calibrated instrument will provide the necessary aircraft radiometric data for radiative transfer and cloud and water vapor retrieval studies. A paper by the PI discussing the potential benefits of passive millimeter and submillimeter wave observations for cloud, water vapor and precipitation measurements has recently been accepted for publication (Gasiewski, 1992), and is included as Appendix A. The MIR instrument is a joint project between NASA/GSFC and Georgia Tech. Other Georgia Tech contributions to the MIR and its related scientific uses have included basic system design studies, performance analyses, and circuit and radiometric load design
“GoBabyGo!” – Rehab Engineering to Make Children Mobile
GoBabyGo! is a project to give children with movement difficulties a chance to move on their own. GoBabyGo! conducts community builds of modified ride-on-cars for these children and grants them mobility. Once issue is that once children have cars, there is no feedback to improve future builds. This project “GoBabyGo!” – Rehab Engineering to Make Children Mobile, wishes to collect quantifiable data on how these cars are being used and how they can be improved. This project aims to do this by collecting surveys from caretakers and through a programmed module to be installed in cars. The installed car module collects specific data about distance and time the child controls the vehicle. Through these collection methods, data can be analyzed to make future suggestions and improvements to new cars
Perceptions of Grade 8-12 Mathematics Teachers on Learner Centred Education (LCE)
The Ministry of Education, Arts and Culture (MEAC) in the Republic of Namibia advocates and encourages teaching in schools through Learner Centred Education (LCE). This call and expectation are evidenced in the vast number of school instructional leadership documents in favour of LCE including the Classroom Observation Instrument (COI), LCE policy [7] and the National Policy Guide for the Junior Primary Phase [15]. However, our 10 years of experience as mentor teachers of Junior Secondary Mathematics teachers suggests that a great number of teachers in schools, including recently trained Mathematics teachers, have a slanted notion of LCE and are subsequently confused as to how to apply this advocated approach in their Mathematics lessons. Thus, the focus of this research project. This research made use of two semi-structured instruments, questionnaires and interviews to explore perceptions of eight Grade 8-12 Mathematics teachers on LCE. All the participating teachers hailed from the two regions of //Kharas and Oshikoto, Namibia. The analysis of data suggests three conclusions with serious implications. First, teacher’s training institutions only practice Teacher Centred Education (TCE). Second, the study also found that Grade 8-12 Mathematics teachers preferred TCE methods to teach Mathematics, in varying Namibian school situations such as large class groups, ill-disciplined learners and even gifted learners, as well as learners who were not eager to learn or ready to perform. However, sometimes TCE does not challenge slower learners to learn and/or think critically and logically. Third, it was found that Grade 8-12 Mathematics teachers needed further training on understanding and applying LCE, as well as training to use technology to teach some topics of Mathematics. Furthermore, the study strongly recommends immediate review of the LCE policy in Namibia
Experimental Effects of Propulsive Jets and Afterbody Configurations on the Zero-lift Drag of Bodies of Revolution at a Mach Number of 1.59
The present investigation was made at a free-stream Mach number of 1.59 to compare the afterbody drags to a series of conical boattailed models at zero angle of attack. Afterbody drags were obtained for both the power-off and the power-on conditions. Power-on drags were obtained as a function of afterbody fineness ratio, jet pressure ratio and divergence, and jet Mach number
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