Spelling suggestions: "subject:"artifacts""
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Compensating for Respiratory Artifacts in Blood Pressure Waveforms / Hemodynamisk kompensering för andningsartefakterWikström, Martin January 2004 (has links)
<p>Cardiac catheterization has for a long time been a valuable way to evaluate the hemodynamics of a patient. One of the benefits is that the entire blood pressure waveform can be recorded and visualized to the cardiologist. These measurements are however disturbed by different phenomenon, such as respiration and the dynamics of the fluid filled catheter, which introduces artifacts in the blood pressure waveform. If these disturbances could be removed, the measurement would be more accurate. This report focuses on the effects of respiratory artifacts in blood pressure signals during cardiac catheterization. </p><p>Four methods, a standard bandpass filter, two adaptive filters and one wavelet based method are considered. The difference between respiratory artifacts in systolic and diastolic pressure is studied and dealt with during compensation. All investigated methods are implemented in Matlab and validated against blood pressure signals from catheterized patients. </p><p>The results are algorithms that try to correct for respiratory artifacts. The rate of success is hard to determine since only a few measured blood pressure signals have been available and since the size and appearance of the actual artifacts are unknown.</p>
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Exploring the effects of different fidelities in an early design process of mobile prototypingDanielsson, Pehr-Henric January 2010 (has links)
<p>There are a vast number of research and studies undertaken within the domain of user-centered design concerning the design process of an artifact, but still there are questions being raised of the relatively new and successful field of mobile design. During recent years mobile technology have surpassed the standardized thoughts of how to prototype and evaluate such a ubiquitous device. The paper addresses this predicament by discussing aspects of fidelity differences in an early design process of a mobile design. The example being presented refers to a design study of an iPhone-application, where two different types of prototypes were created and user tested, a low-fidelity paper prototype and a mixed-fidelity interactive prototype. The paper sets focus on the various differences between these fidelities closely related to the case. It also reflects on how mobile design approaches can mature during the early stages of a design process.</p>
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加速器質量分析計を用いた鉄製遺物の14C年代測定に関する基礎研究NAKAMURA, Toshio, KONDO, Hiroki, 中村, 俊夫, 近藤, 宏樹 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
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”Det är ju troligen inte en overheadapparat de kommer att använda sig av i framtiden…” : Om skolans tekniksprång, en undersökning om datorns användning på gymnasietEinarsson, Marie January 2012 (has links)
The aim of this qualitative respondent investigation is to delve into the various views that teachers have concerning the “One-to-One project”, as well as the use of computers as an aid in teaching. One-to-One means that teachers and students will be equipped with a laptop they can use at home and at school.This essay looks at how several factors have changed as a result of this. These factors are threefold: the role of the teacher, the teaching experience, and the student´s learning process. In order to answer the mentioned questions, four interviews have been conducted at two different high schools in southern Norrland. The theory used is the socio-cultural perspective. One result has been that computers can simplify teaching in various ways. Students have faster access to information, and there exists a platform for further communication between the teacher and student outside the classroom. However, there are also several negative aspects. One of these is that the students spend time doing non-school related activities, such as interacting using social mediums. Results also show that the role of the teacher has due to the "One-to-One project" gone from being structural to being interactional. The conclusions reached by the investigation are that today’s schools are experiencing a paradigm shift. Old teaching methods are being replaced by new methods and an altered teaching practice has developed as a result of the presence of the computer in the classroom.
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Health Information Systems Affordances: How the Materiality of Information Technology Enables and Constrains the Work Practices of CliniciansAnderson, Chad 11 August 2011 (has links)
The IT artifact is at the core of the information systems (IS) discipline and yet most IS research does not directly theorize the IT artifact or its nomological network (Benbasat and Zmud 2003; Orlikowski and Iacono 2001). This research seeks to answer a repeated call for more direct engagement with the IT artifact and its nomological net with affordance theory adopted as the basis for this theoretical work. An exploratory case study was conducted to answer the research question, how do the material properties of health information systems enable and constrain the work practices of clinicians? The study was conducted at a large urban acute care hospital in the Midwestern United States with registered nurses working on inpatient care units as the clinicians of interest. Through interviews with nurses and other clinical stakeholders and the observation of nurse’s work practices on three patient care units in the hospital, theoretical insights were developed on the nature of affordances for information systems research. IS affordances are defined in this study as relationships between abilities of an individual and features of an information systems within the context of the environment in which they function. The concepts of an affordance range and an affordance threshold are proposed as theoretical constructs in the nomological network of affordances that help to explain the use of information systems as a function of the difficulty of acting on IS affordances. The relationship between affordances and constraints is theorized and linked to the affordance range and threshold with the assertion that constraints are closely associated with the difficulties experienced by users in acting on IS affordances. The challenge of studying IS affordances in all their complexity is discussed with the suggestion that researchers take the user’s perspective of affordances to alleviate the need for repeated decomposition. Finally, the role of information systems in facilitating social interaction is emphasized through the concept of affordances for sociality. The contribution of this research to the IS field is a more nuanced understanding of the nature of the IT artifact and its relationship to the users of that technology.
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Exploring the effects of different fidelities in an early design process of mobile prototypingDanielsson, Pehr-Henric January 2010 (has links)
There are a vast number of research and studies undertaken within the domain of user-centered design concerning the design process of an artifact, but still there are questions being raised of the relatively new and successful field of mobile design. During recent years mobile technology have surpassed the standardized thoughts of how to prototype and evaluate such a ubiquitous device. The paper addresses this predicament by discussing aspects of fidelity differences in an early design process of a mobile design. The example being presented refers to a design study of an iPhone-application, where two different types of prototypes were created and user tested, a low-fidelity paper prototype and a mixed-fidelity interactive prototype. The paper sets focus on the various differences between these fidelities closely related to the case. It also reflects on how mobile design approaches can mature during the early stages of a design process.
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Compensating for Respiratory Artifacts in Blood Pressure Waveforms / Hemodynamisk kompensering för andningsartefakterWikström, Martin January 2004 (has links)
Cardiac catheterization has for a long time been a valuable way to evaluate the hemodynamics of a patient. One of the benefits is that the entire blood pressure waveform can be recorded and visualized to the cardiologist. These measurements are however disturbed by different phenomenon, such as respiration and the dynamics of the fluid filled catheter, which introduces artifacts in the blood pressure waveform. If these disturbances could be removed, the measurement would be more accurate. This report focuses on the effects of respiratory artifacts in blood pressure signals during cardiac catheterization. Four methods, a standard bandpass filter, two adaptive filters and one wavelet based method are considered. The difference between respiratory artifacts in systolic and diastolic pressure is studied and dealt with during compensation. All investigated methods are implemented in Matlab and validated against blood pressure signals from catheterized patients. The results are algorithms that try to correct for respiratory artifacts. The rate of success is hard to determine since only a few measured blood pressure signals have been available and since the size and appearance of the actual artifacts are unknown.
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Image/Video Deblocking via Sparse RepresentationChiou, Yi-Wen 08 September 2012 (has links)
Blocking artifact, characterized by visually noticeable changes in pixel values along block boundaries, is a common problem in block-based image/video compression, especially at low bitrate coding. Various post-processing techniques have been proposed to reduce blocking artifacts, but they usually introduce excessive blurring or ringing effects. This paper proposes a self-learning-based image/ video deblocking framework via properly formulating deblocking as an MCA (morphological component analysis)-based image decomposition problem via sparse representation. The proposed method first decomposes an image/video frame into the low-frequency and high-frequency parts by applying BM3D (block-matching and 3D filtering) algorithm. The high-frequency part is then decomposed into a ¡§blocking component¡¨ and a ¡§non-blocking component¡¨ by performing dictionary learning and sparse coding based on MCA. As a result, the blocking component can be removed from the image/video frame successfully while preserving most original image/video details. Experimental results demonstrate the efficacy of the proposed algorithm.
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Conserving Waterlogged Rope: A Review of Traditional Methods and Experimental Research with Polyethylene GlycolMcCaskill, Jennifer R. 16 January 2010 (has links)
The excavation of Sieur de la Salle's ship, La Belle, yielded a large amount of
waterlogged rope requiring conservation. A history of hemp and rope manufacture is
reviewed to assist in the identification of the materials and rope-work recovered from the
La Belle, as well as to assist in selecting an appropriate conservation treatment.
A summary of several methods used to conserve cordage is presented. Time has
shown that not all of these treatment methods have remained viable options, and that
continued study and experimentation are needed so that the conservator has the tools to
develop an appropriate conservation plan for each artifact.
The majority of La Belle's cordage was conserved using the passivation
polymers method developed by Dr. C. Wayne Smith and Dr. Donny L. Hamilton, both
of Texas A&M University, in conjunction with Dow Corning Corporation, Midland,
Michigan. An experiment applying knowledge gleaned from the passivation polymers
process to polyethylene glycol (PEG) impregnation was conducted in an attempt to
stabilize the PEG within the rope. The results were good; the rope retained some
flexibility and appears stable with a slightly darker color than with silicone oil.
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Fort Walton ceramics in the Perry Collection, Apalachicola Valley, Northwest FloridaYuellig, Amber J 01 June 2007 (has links)
Fort Walton, the local variant of Mississippian culture in northwest Florida, has long been studied in the Apalachicola River Valley beginning in the early 1900s, most notably by Clarence B. Moore (though he did not call it Fort Walton), and has continued to intrigue archaeologists and collectors alike. Gordon Willey and Richard Woodbury were the first to create a ceramic chronology for the Florida Gulf Coast. Willey continued this work, resulting in the publication of Archeology of the Florida Gulf Coast, an impressive compilation of information on prehistoric cultures, sites, and their ceramic technologies and typologies. This book has continued to be most widely accepted reference for Fort Walton ceramics. This thesis builds on knowledge of ceramic seriations for the Apalachicola River Valley, working toward a more accurate chronology. Two sources of data are utilized in this study. Each comes from the Curlee Site (8Ja7), in Jackson County, Florida, just south of the Jim Woodruff Dam near the top of the Apalachicola River.
The first, the Leon Perry Collection, is an unprovenienced collection donated to the University of South Florida. The second, the Cleveland Museum of Natural History Collection, consists of excavated data and materials collected in the late 1970s. Over 10,000 sherds were documented in the Leon Perry Collection. Type, weight, vessel shape, temper, and decorative attributes of each sherd were recorded. The type Fort Walton Incised in this collection revealed several variations of scroll designs increasingly varied through time. Commonalities were found between Lake Jackson Plain and Lake Jackson Incised types. These two should should be consolidated into one ceramic type. Ceramics from the Cleveland Museum of Natural History collection were reexamined by White and Yuellig in the spring of 2006 with consideration toward patterns found in Fort Walton Incised and Lake Jackson types in the Leon Perry Collection.
Trends in the stratigraphic distribution of these patterns were documented in order to test whether they could result in better temporal control. This research serves as a case study in how knowledge gained from an unprovenienced collection can shed new light on archaeological data with temporal control.
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