Experimental and analytical investigation of refrigerant and lubricant migration

The off-cycle refrigerant mass migration has a direct influence on the on-cycle performance since compressor energy is necessary to redistribute the refrigerant mass. No studies, as of today, are available in the open literature which experimentally measured the lubricant migration within a refrigeration system during cycling or stop/start transients. Therefore, experimental procedures measuring the refrigerant and lubricant migration through the major components of a refrigeration system during stop/start transients were developed and implemented. Results identifying the underlying physics are presented. The refrigerant and lubricant migration of an R134a automotive A/C system-utilizing a fixed orifice tube, minichannel condenser, plate and fin evaporator, U-tube type accumulator and fixed displacement compressor-was measured across five sections divided by ball valves. Using the Quick-Closing Valve Technique (QCVT) combined with the Remove and Weigh Technique (RWT) using liquid nitrogen as the condensing agent resulted in a measurement uncertainty of 0.4 percent regarding the total refrigerant mass in the system. The determination of the lubricant mass distribution was achieved by employing three different techniques-Remove and Weigh, Mix and Sample, and Flushing. To employ the Mix and Sample Technique a device-called the Mix and Sample Device-was built. A method to separate the refrigerant and lubricant was developed with an accuracy-after separation-of 0.04 grams of refrigerant left in the lubricant. When applying the three techniques, the total amount of lubricant mass in the system was determined to within two percent. The combination of measurement results-infrared photography and high speed and real time videography-provide unprecedented insight into the mechanisms of refrigerant and lubricant migration during stop-start operation. During the compressor stop period, the primary refrigerant mass migration is caused by, and follows, the diminishing pressure difference across the expansion device. The secondary refrigerant migration is caused by a pressure gradient as a result of thermal nonequilibrium within the system and causes only vapor phase refrigerant migration. Lubricant migration is proportional to the refrigerant mass during the primary refrigerant mass migration. During the secondary refrigerant mass migration lubricant is not migrating. The start-up refrigerant mass migration is caused by an imbalance of the refrigerant mass flow rates across the compressor and expansion device. The higher compressor refrigerant mass flow rate was a result of the entrainment of foam into the U-tube of the accumulator. The lubricant mass migration during the start-up was not proportional to the refrigerant mass migration. The presence of water condensate on the evaporator affected the refrigerant mass migration during the compressor stop period. Caused by an evaporative cooling effect the evaporator held 56 percent of the total refrigerant mass in the system after three minutes of compressor stop time-compared to 25 percent when no water condensate was present on the evaporator coil. Foam entrainment led to a faster lubricant and refrigerant mass migration out of the accumulator than liquid entrainment through the hole at the bottom of the U-tube. The latter was observed for when water condensate was present on the evaporator coil because-as a result of the higher amount of refrigerant mass in the evaporator before start-up-the entrainment of foam into the U-tube of the accumulator ceased before the steady state refrigerant mass distribution was reached.

No right to sext? A critical examination of media and legal debates about teenage girls' sexual agency in the digital age

Advances in digital photography and distribution technologies enable many people to produce and distribute images of their sex acts. When teenagers do this, the photos and videos they create can be legally classified as child pornography since the law makes no exception for youth who create sexually explicit images of themselves. The dominant discussions about teenage girls producing sexually explicit media (including sexting) are profoundly unproductive: (1) they blame teenage girls for creating private images that another person later maliciously distributed and (2) they fail to respect—or even discuss—teenagers’ rights to freedom of expression. Cell phones and the internet make producing and distributing images extremely easy, which provide widely accessible venues for both consensual sexual expression between partners and for sexual harassment. Dominant understandings view sexting as a troubling teenage trend created through the combination of camera phones and adolescent hormones and impulsivity, but this view often conflates consensual sexting between partners with the malicious distribution of a person’s private image as essentially equivalent behaviors. In this project, I ask: What is the role of assumptions about teen girls’ sexual agency in these problematic understandings of sexting that blame victims and deny teenagers’ rights? In contrast to the popular media panic about online predators and the familiar accusation that youth are wasting their leisure time by using digital media, some people champion the internet as a democratic space that offers young people the opportunity to explore identities and develop social and communication skills. Yet, when teen girls’ sexuality enters this conversation, all this debate and discussion narrows to a problematic consensus. The optimists about adolescents and technology fall silent, and the argument that media production is inherently empowering for girls does not seem to apply to a girl who produces a sexually explicit image of herself. Instead, feminist, popular, and legal commentaries assert that she is necessarily a victim: of a “sexualized” mass media, pressure from her male peers, digital technology, her brain structures or hormones, or her own low self-esteem and misplaced desire for attention. Why and how are teenage girls’ sexual choices produced as evidence of their failure or success in achieving Western liberal ideals of self-esteem, resistance, and agency? Since mass media and policy reactions to sexting have so far been overwhelmingly sexist and counter-productive, it is crucial to interrogate the concepts and assumptions that characterize mainstream understandings of sexting. I argue that the common sense that is co-produced by law and mass media underlies the problematic legal and policy responses to sexting. Analyzing a range of nonfiction texts including newspaper articles, talk shows, press releases, public service announcements, websites, legislative debates, and legal documents, I investigate gendered, racialized, age-based, and technologically determinist common sense assumptions about teenage girls’ sexual agency. I examine the consensus and continuities that exist between news, nonfiction mass media, policy, institutions, and law, and describe the limits of their debates. I find that this early 21st century post-feminist girl-power moment not only demands that girls live up to gendered sexual ideals but also insists that actively choosing to follow these norms is the only way to exercise sexual agency. This is the first study to date examining the relationship of conventional wisdom about digital media and teenage girls’ sexuality to both policy and mass media.

Improving the assessment and outcome of free tissue transfer breast reconstruction

Introduction: Free tissue transfer using an abdominal tissue flap is a commonly used method of breast reconstruction. However, there are well recognised complications including venous congestion, fat necrosis and flap loss associated with the perfusion of these flaps. Post-operative aesthetic outcome assessment of such breast reconstructions have also proven to be difficult with current methods displaying poor inter-rater reliability and patient correlation. The aim of this research was to investigate potential improvements to the post-operative outcome of free abdominal tissue transfer breast reconstruction by assessing the effects of vascular augmentation interventions on flap perfusion and to assess the use of real-time digital video as a post-operative assessment tool. Methods: An in-vivo pilot study carried out on 12 patients undergoing DIEP flap breast reconstruction assessed the effect on Zone IV perfusion, using LDI and ICG angiography, of vascular augmentation of the flap using the contralateral SIEA and SIEV. A further animal experimental study was carried out on 12 Sprague Dawley rats to assess the effects on main pedicle arterial blood flow and on Zone I and Zone IV perfusion of vascular augmentation of the abdominal flap using the contralateral vascular system. A separate post-operative assessment study was undertaken on 35 breast reconstruction patients who evaluated their own reconstructions via patient questionnaire and underwent photograph and real-time digital video capture of their reconstructions with subsequent panel assessment. Results: Our results showed that combined vascular augmentation of DIEP flaps, using both the SIEA and SIEV together, led to an increase in Zone IV perfusion. Vascular augmentation of the rat abdominal flaps also led to a significant increase in Zone I/IV perfusion, but the augmentation procedure resulted in a decreased main pedicle arterial blood flow. Our post-operative assessment study revealed that real-time digital video footage led to greater inter-rater agreement with regards to cosmesis and shape than photography and also correlated more with patient self-assessment. Conclusion: Vascular augmentation of abdominal free tissue flaps using the contralateral vascular system results in an increase to Zone IV perfusion, however this may lead to decreased main pedicle arterial blood flow. Real-time digital video is a valid post-operative aesthetic assessment method of breast reconstruction outcome and is superior to static photography when coupled with panel assessment.

"Am I Korean American?": beliefs and practices of parents and children living in two languages and two cultures

The purpose of this study is to explore attitudes and practices regarding their heritage language and the dominant English language among Korean American immigrant families. Using the framework of Language Ideology (Silverstein, 1979), I had three research questions: a) why do parents send their children to a Korean language school, b) what attitudes do immigrant parents and their children show toward Korean and English, and c) how are the parents and children involved in the practices of these two languages? I conducted a survey of parents whose children attended a Korean language school in Urbana-Champaign, Illinois, where the number of Korean sojourners (temporary residents) exceeds that of Korean immigrants. Forty participant parents provided demographic information. They described their children's language-use patterns depending on interlocutors as well as their language proficiency in both Korean and English. The reasons for sending their children to the Korean language school were significantly different depending on the respondents' residential status. In comparison to the sojourners, immigrants tended to give more priority to their children's oral language development and Korean identity construction. I also conducted case studies of three Korean immigrant families with 3- to 5-year-old children, using interviews, observations, and photographs of children's work. The collected data were analyzed according to themes such as daily life, parental beliefs about two languages, practices in two languages, children's attitudes toward two languages, and challenges and needs. Despite individual families' different immigration histories, the three families faced some common challenges. Because of their busy daily routines and different lifestyles, the immigrant families had limited interactions with other Koreans. The parents wanted their children to benefit from two communities and build a combined ethnic identity as Korean Americans. I argue that a Korean language school should expand its role as a comfort zone for all Koreans and Korean Americans. This study explores the heterogeneity among Korean sojourner and immigrant families and their language use and identity construction.

Tourist Destination Image in the New Technological Environments: Dialogism under the Public Relations Gaze

The dependence and influence of new media on social and organizational life have led to a new orientation of the communicational practices of organizations and to a research paradigm shift to a cocriational model within public relations theory. This model is based on dialogic rhetoric and dialogue that requires a joint production of content and meanings by organizations and publics, which have a central role in shaping image. The new social and communicational paradigms have also an impact on tourism research, implying the need to understand the role of new technologies, particularly websites, in image formation. The purpose of this study is to investigate the role of website in the formation of a tourist destination image (Portugal) through the understanding of the degree of adoption of dialogical principles on websites by official and unofficial tourist organizations and the identifying of denotative and connotative elements that are represented on published and shared photographs in these websites. The research corpus consisted of websites of entities and photographs published and shared on these websites. The methodology used is quantitative and qualitative, based on content analysis of data of websites and photographs. Results indicate that official tourist entities adopted the dialogic principles in a higher degree than unofficials. There is also a higher adoption of the principles related to technical dimension than dialogical dimension. Results confirm a relation between the adoption of dialogical link and an increased openness by entities to the possibility of photo sharing. The analysis of denotative and connotative elements of photography reflects a similarity in representations of entities and tourists. This study contributes to both theoretical perspectives, because it provides a conceptual scheme of destination image formation online and to a practical perspective, because it also suggests guidelines of dialogical practices to incorporate in websites of tourism entities.

Contested Play and Clean Water: McMillan Park, Race, and the Built Environment in Washington, D.C., 1900-1941

This study focuses on the intersection of the politics and culture of open public space with race relations in the United States from 1900 to 1941. The history of McMillan Park in Washington, D.C. serves as a lens to examine these themes. Ultimately, the park’s history, as documented in newspapers, interviews, reports, and photographs, reveals how white residents attempted to protect their dominance in a racial hierarchy through the control of both the physical and cultural elements of public recreation space. White use of discrimination through seemingly neutral desires to protect health, safety, and property values, establishes a congruence with their defense of residential property. Without similar access to legal methods, African Americans acted through direct action in gaps of governmental control. Their use of this space demonstrates how African-American residents of Washington and the United States contested their race, recreation, and spatial privileges in the pre-World War II era.

Underwater survey of ichthyofauna of eastern Atlantic seamounts: Gettysburg and Ormond (Gorringe Bank)

Gettysburg and Ormond are seamounts belonging to the Gorringe Bank, which is located on the Europen-African plate boundary. Given the importance of these oceanic features for understanding marine biodiversity patterns, two surveys were carried out in 1998 (Gettysburg) and 1999 (Ormond) using diving, photography and video for species identification and abundance evaluation. Of the 9 fish species found at Gettysburg and 11 at Ormond, 6 were common to both sites and these included the dominant species: the oceanic and commercially important, Seriola rivoliana, and the coastal, typically Atlantic-Mediterranean Coris julis and Anthias anthias. The strong representation of coastal, demersal and Atlantic-Mediterranean species in the Gorringe Bank region and the presence of Abudefduf luridus, an endemic Macaronesian species, at Gettysburg suggests that the upper part of these seamounts may have acted and still act as “stepping stones” for the dispersal of coastal species.

New insight on the underdrawing of 16th Flemish-Portuguese easel paintings by combined surface analysis and microanalytical techniques

This paper focusses on the study of the underdrawings of 16th century easel paintings attributed to the workshop of the Portuguese-Flemish Master Frei Carlos. This investigation encompasses multidisciplinary research that relates the results of surface exams (infrared reflectography, standard light photography and infrared photography) with analytical investigations. The surface analysis of Frei Carlos’ underdrawings by infrared reflectography has shown heterogeneous work, revealing two different situations: (1) an abundant and expressive underdrawing, revealing a Flemish influence and (2) a simple and outlined underdrawing. This preliminary research raised an important question related to this Portuguese-Flemish workshop and to the analytical approach: Is the underdrawing's heterogeneity, as observed in the reflectograms, related to different artists or is this rather an effect that is produced due to the use of different materials in the underdrawing's execution? Consequently, if different materials were used, how can we have access to the hidden underdrawings? In order to understand the reasons for this dissemblance, chemical analysis of micro-samples collected in underdrawing areas and representing both situations were carried out by optical microscopy, micro Fourier transform infrared spectroscopy (μ-FTIR), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDX) and micro-Raman spectroscopy (μ-Raman). Taking into account the different possibilities and practical and theoretical limitations of surface and punctual examinations in the study of easel painting underdrawings, the methodology of research was adjusted, sometimes resulting in a re-analysis of experimental results. This research shows the importance of combining multispectral surface exams and chemical analysis in the understanding of the artistic creative processes of 16th century easel paintings.

Many Mount Barrens

Cibachrome photographic prints, Digital print, Acrylic Sheet , wire & card.--------- Total size: 170cm x 119cm x 15cm---------- The work employs a terrestrial photography and cartographic technique to represent a diversity of landscape types surrounding West Mt Barren in Western Australia. Sixteen views of West Mt Barren were captured over a two week period from map grid coordinates in the surround landscape. These images are configured in Many Mount Barrens in a manner which corresponds to the position from which they were recorded.---------- The work was exhibited at Eyes wide open (curators K Bradby and A Brandenberg) which was held at Gorepani Gallery, Albany WA to coincide with the first national screening on SBS Television of the Western Australian documentary A Million Acres a Year (Rijavec, F, Harrison, N & Bradby K (directors), Snakewood Films & Film Australia, c2003).

Incorporating community history into urban redevelopment

A community history project must be relevant to each person within it so that they see themselves as part of the socio-cultural fabric of the area and feel a sense of ownership of their environment. The Mill Albion community history project is a diverse, multi-layered public history/art program that captures the social heritage of The Mill Albion and allows the community to contribute to their ongoing history. The Albion Flour Mill was built in 1930 at a time when Australia was feeling the effects of its worst economic depression and continued operations for more than 72 years. After ceasing operation in 2005 the site was left to deteriorate. The FKP Property Group purchased the land to undertake a new urban redevelopment project, drawing on the design principles of a traditional ‘village’, while valuing the importance of remembering the community that once included the Flour Mill. This paper reflects on the this project and showcases some of the culturally creative ways this community’s history was told, using methods such as digital stories, contemporary and historical photography and oral history.

Everything

Everything (2008) is a looped 3 channel digital video (extracted from a 3D computer animation) that appropriates a range of media including photography, drawing, painting, and pre-shot video. The work departs from traditional time-based video which is generally based on a recording of an external event. Instead, “Everything” constructs an event and space more like a painting or drawing might. The works combines constructed events (including space, combinations of objects, and aesthetic relationship of forms) with pre-recorded video footage and pre-made paintings and drawings. The result is a montage of objects, images – both still and moving – and abstracted ‘painterly’ gestures. This technique creates a complex temporal displacement. 'Past' refers to pre-recorded media such as painting and photography, and 'future' refers to a possible virtual space not in the present, that these objects may occupy together. Through this simultaneity between the real and the virtual, the work comments on a disembodied sense of space and time, while also puncturing the virtual with a sense of materiality through the tactility of drawing and painting forms and processes. In so doing, te work challenges the perspectival Cartesian space synonymous with the virtual. In this work the disembodied wandering virtual eye is met with an uncanny combination of scenes, where scale and the relationships between objects are disrupted and changed. Everything is one of the first international examples of 3D animation technology being utilised in contemporary art. The work won the inaugural $75,000 Premier of Queensland National New Media Art Award and was subsequently acquired by the Queensland Art Gallery. The work has been exhibited and reviewed nationally and internationally.

The way

In this wall-mounted sculpture, a car stereo is mounted into a photographic image of a redwood forest. It plays a sparse and evocative guitar soundtrack. The supporting cabinet is finished with timber veneer to resemble a retro home stereo or piece of designer furniture. This work examines how we construct, represent and deploy notions of nature in our contemporary lives. It mixes the languages of furniture design, landscape photography and sculpture. Drawing on Zygmunt Bauman’s theoretical work on “liquid modernity”, this work questions how and where we find space for contemplation and reflection in a contemporary context increasingly defined by temporary social bonds and consumer choices.

Peace unknown

In this freestanding sculpture, domestic ‘in-wall’ speakers are mounted in custom-built cabinets. The speakers play a calming stock music soundtrack. The cabinets are faced with photographic mural wallpaper of a stereotypical waterfall scene. This work examines how we construct, represent and deploy notions of nature in our contemporary lives. It mixes the languages of furniture design, landscape photography and sculpture. Drawing on Zygmunt Bauman’s theoretical work on “liquid modernity”, this work questions how and where we find space for contemplation and reflection in a contemporary context increasingly defined by temporary social bonds and consumer choices.

Outcrop

In this wall-mounted sculpture, speakers are mounted into a timber-veneered cabinet. The speakers play a dark, searching soundtrack. Also mounted on the cabinet is a photographic image of a rocky gully in the American desert. This work examines how we construct, represent and deploy notions of nature in our contemporary lives. It mixes the languages of furniture design, landscape photography and sculpture. Drawing on Zygmunt Bauman’s theoretical work on “liquid modernity”, this work questions how and where we find space for contemplation and reflection in a contemporary context increasingly defined by temporary social bonds and consumer choices.

Visualising the 48 hour game making challenge

We have always felt that “something very special” was happening in the 48hr and other similar game jams. This “something” is more than the intensity and challenge of the experience, although this certainly has appeal for the participants. We had an intuition that these intense 48 hour game jams exposed something pertinent to the changing shape of the Australian games industry where we see the demise of the late 20th century large studio - the “Night Elf” model and the growth of the small independent model. There are a large number of wider economic and cultural factors around this evolution but our interest is specifically in the change from “industry” to “creative industry” and the growth of games as a cultural media and art practice. If we are correct in our intuition, then illuminating this something also has important ramifications for those courses which teach game and interaction design and development. Rather than undertake a formal ethno-methodological approach, we decided to track as many of the actors in the event as possible. We documented the experience (Keith Novak’s beautiful B&W photography), the individual and their technology (IOGraph mouse tracking), the teams as a group (Time lapse photography) and movement tracking throughout the whole space (Blue tooth phone tracking). The raw data collected has given us opportunity to start a commentary on the “something special” happening in the 48hr.