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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Single Jet Impingement Cooling in a Roughened Rotating Square Duct

Tsai, Hsiu-Huang 24 July 2001 (has links)
Abstract The experiments was studied on a rotating ribbed square duct from two different impingement position of air jets (termed as Type A and B) and at rotational speeds of 0,300 and 600 rpm¡CThe jet impinged on two different geometric types of rib (square and semi-circular ribs). The study covered jet Reynolds number 5000 to 9000 and the jet rotation number was varied from 0 to 0.0053. Results are presented and focused on the effect of two of circular jet arrangements and different geometric of ribs. Significant heat transfer enhancement was found for Type A configuration and square ribs within the ranges of operating parameters considered in the study. However, rotation induced Coriolis and centrifuged forces decreased the Nusselt number values (up to 20%) which is quitely conincided with those of previous studies.
2

Assessment of Sexual Dimorphism on the First and Second Ribs: Exploring Geometric Morphometrics

Unknown Date (has links)
Estimating the sex of unknown human skeletal remains is important to the fields of forensic anthropology, bioarchaeology, and other specialties. I studied sexual dimorphism on the first and second ribs to estimate sex from skeletal remains. I employed two approaches. I used geometric morphometrics to analyze landmark and semilandmark coordinate points to examine the overall shape of the ribs. I also examined the sternal end of the ribs for size using the superior-inferior height (SIH) and anteriorposterior breadth (APB) in a binary logistic regression (BLR) model. Differences in male and female first and second ribs are undetectable when landmark coordinate points are used to capture shape variability, but significant differences in the shape of the ribs, however, are detected through the use of semilandmark coordinate points. Using semilandmark points to estimate sex presented an accuracy rate of 80.7% from the first rib, and 72.9% from the second rib. The use of the sternal end presents consistent results in its ability to estimate sex with an accuracy rate of 84.2%. The BLR model reveals significant differences between males and females than the geometric morphometric approach; it is more applicable for discerning sexual dimorphism of unknown individuals. This study reveals that while geometric morphometrics provides a powerful approach to assessing morphological differences, it is not always better than simpler methods, in this case, simple measurements analyzed through BLR. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
3

Heat Transfer in Smooth and Ribbed Rectangular Two-Pass Channels with a Developing Flow Entrance at High Rotation Numbers

Huh, Michael 16 January 2010 (has links)
Cooling channels with a developing flow entrance condition and aspect ratios of 1:4 and 2:1 were studied. The range of the rotation number and buoyancy parameter for the selected AR channels was extended. The maximum Ro and Bo for the 1:4 channel was 0.67 and 1.9, respectively. For the 2:1 channel, these values were 0.45 and 0.85, respectively. The effect of rib spacing and rib height on heat transfer in the 1:4 channel is investigated. Three rib spacing configurations were considered: P/e=2.5, 5, 10 with a constant e/Dh ratio of 0.078. To investigate the effect of rib height, a rib configuration with an e/Dh ratio of 0.156 and P/e ratio of 10 was considered. For the 2:1 channel, a smooth channel surface condition was studied. For each channel aspect ratio and surface condition, five Reynolds numbers were studied up to 40K. At each Re, five rotational speeds are considered up to 400 rpm. The results of this research work indicate that rotation can cause a significant increase in heat transfer on the first pass trailing surface of both aspect ratio channels. The leading surface in ribbed channels has shown a dramatic decrease in heat transfer with rotation in the first pass. Reductions in heat transfer by as much as 50% were observed. In the second pass, the leading and trailing surfaces with ribs showed very similar effects of rotation. Also, the effect of rotation seems to vary with the rib spacing. The strength of rotation showed to be greater in the tight rib spacing of P/e=2.5. The rib height in the 1:4 channel had minimal impact due to the large distance between the leading and trailing surfaces. The tip cap heat transfer for both channels showed large increases with rotation. This is very beneficial since tip cooling is an important part of maintaining the life a turbine blade. Finally, the buoyancy parameter proved to be very useful in predicting heat transfer in rotating conditions. The correlations developed showed very acceptable accuracy when compared to the experimental data.
4

Chirurgická léčba nestabilních zlomenin sterna a žeber / THE SURGICAL TREATMENT OF UNSTABLE FRACTURES OF STERNUM AND RIBS

Šimánek, Václav January 2007 (has links)
The injury of chest belongs to most frequented injuries. As far as 70 per cent of injuries of thorax is connected with injury of other organs. The relevance of injury of chest increases with age. The prognosis of polytraumatized patients with injury of thorax is aggravated in combination with craniocerebral injury. 50 per cent of death caused by injuries is connected with trauma of chest. The trauma of thorax are most frequently blunt. The open injuries are heavier. The main reason of blunt injuries of chest are road traffic accidents. 80 per cent of open injuries are created by shooting weapons or by stabbing. The fractures of ribs belong to most frequent types of fractures and simultaneously to the most types of injuries of thorax. The multiple fractures of ribs are serious. From 10 to 20 per cent of fractures of ribs have the manifestation of paradox breathing. The unstable fractures of ribs are classified after Pate and Eschapasse-Gailard. The conservative and operative types of treatment are used for stabilization of chest wall. The opinion on usage of this treatment are not unified. The artificial lung ventilation with low PEEP is used during conservative treatment. Operative treatment utilizes the external or internal fixation of unstable fragments of chest wall. At the Department of Surgery,...
5

The effectiveness of first rib adjustment as an adjunct to the treatment of mechanical neck pain

Brown, Colin Douglas January 2006 (has links)
Thesis (M.Tech.: Chiropractic)- Dept. of Chiropractic, Durban Institute of Technology, 2006. 130 leaves. / The purpose of this investigation was to evaluate the efficacy of the adjustment of the first rib as an adjunct to the manipulative treatment of mechanical neck pain, according to subjective and objective clinical findings. The results of this study would indicate to Chiropractors which specific types of adjustments, used for the treatment of mechanical neck pain, would potentially increase the cervical range of motion and / or decrease pain experienced by the patient and thus lead to a more effective treatment protocol. The outcome of the study will help clinicians select the more appropriate treatment for patients based on the subjective and objective outcomes.
6

Internal crossflow effects on turbine airfoil film cooling adiabatic effectiveness with compound angle round holes

Klavetter, Sean Robert 07 October 2014 (has links)
Internal crossflow is an important element to actual gas turbine blade cooling; however, there are very few studies in open literature that have documented its effects on turbine blade film cooling. Experiments measuring adiabatic effectiveness were conducted to investigate the effects of perpendicular crossflow on a row of 45 degree compound angle, cylindrical film cooling holes. Tests included a standard plenum condition, a baseline crossflow case consisting of a smooth-walled channel, and various crossflow configurations with ribs. The ribs were angled to the direction of prevailing internal crossflow at 45 and 135 degrees and were positioned at different locations. Experiments were conducted at a density ratio of DR=1.5 for a range of blowing ratios including M=0.5, 0.75, 1.0, 1.5, and 2.0. Results showed that internal crossflow can significantly influence adiabatic effectiveness when compared to the standard plenum condition. The implementation of ribs generally decreased the adiabatic effectiveness when compared to the smooth-walled crossflow case. The highest adiabatic effectiveness measurements were recorded for the smooth-walled case in which crossflow was directed against the spanwise hole orientation angle. Tests indicated that the direction of perpendicular crossflow in relation to the hole orientation can significantly influence the adiabatic effectiveness. Among the rib crossflow tests, rib configurations that directed the coolant forward in the direction of the mainstream resulted in higher adiabatic effectiveness measurements. However, no other parameters could consistently be identified correlating to increased film cooling performance. It is likely that a combination of factors are responsible for influencing performance, including internal local pressure caused by the ribs, the internal channel flow field, jet exit velocity profiles, and in-hole vortices. / text
7

The effectiveness of first rib adjustment as an adjunct to the treatment of mechanical neck pain

Brown, Colin Douglas January 2006 (has links)
A dissertation submitted in partial compliance with the requirements for a Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2006. / The purpose of this investigation was to evaluate the efficacy of the adjustment of the first rib as an adjunct to the manipulative treatment of mechanical neck pain, according to subjective and objective clinical findings. The results of this study would indicate to Chiropractors which specific types of adjustments, used for the treatment of mechanical neck pain, would potentially increase the cervical range of motion and / or decrease pain experienced by the patient and thus lead to a more effective treatment protocol. The outcome of the study will help clinicians select the more appropriate treatment for patients based on the subjective and objective outcomes. / M
8

A Study of Carasaurus' (Dinosaura: Sauropodomorph) Torso and its Biomechanical Implications

Wood, Jacqueline Mary 22 May 2006 (has links)
Physical examination of the articulations between the dorsal vertebrae and the dorsal ribs of the sauropod dinosaur Camarasaurus (Upper Cretaceous, Wyoming or whatever) shows that the dorsal vertebral column has a slight double curve and the torso is more narrow and volumetrically smaller than previously reconstructed. The shape of the dorsal vertebrae series was based upon the position of the zygopophyses and centrum spacing. The dorsal ribs were placed on the vertebrae based upon the position of tuberculum/diapophysis, capitulum/parapophysis, and the lateral edge of the rib head. Comparisons between the articulated torso of Camarasaurus and extant relatives allowed for the first attempt in reconstructing the three intercostal muscle groups. The newly defined torso shape in combination with the presence of scapular facets on the ribs allowed the scapulocoracoid to be placed upon the torso at an angle of 20-30°.
9

Estimating sexual dimorphism from sternal rib ends /

Gavit, Kristina Rhea, January 1900 (has links)
Thesis (M.A.)--Texas State University--San Marcos, 2009. / Vita. Appendix: leaves 28-40. Includes bibliographical references (leaves 41-43). Also available on microfilm.
10

Chest wall sarcomas

Widhe, Björn, January 2010 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2010.

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