title: A comparison of two methods for assessing critical flicker fusion frequency in hens

authors: Railton, Renee Caron Richards

subjects: conditional discrimination

abstract: This paper compared two general methods for assessing critical fusion frequency in hens (gallus gallus domesticus). The first method was a conditional discrimination procedure with the stimuli presented successively. The second was a two-alternative forced-choice procedure with the stimuli presented simultaneously. It was found that both methods of stimulus presentation gave comparable results suggesting that either method is useful when investigating psychophysics in animals. The results also show that hens’ critical fusion frequency is considerably higher than that of humans which may account for hens’ inability to recognise images presented on standard computer or television monitors.

text: A comparison of two methods for assessing critical flicker fusion frequency in hens This paper compared two general methods for assessing critical fusion frequency in hens (gallus gallus domesticus). The first method was a conditional discrimination procedure with the stimuli presented successively. The second was a two-alternative forced-choice procedure with the stimuli presented simultaneously. It was found that both methods of stimulus presentation gave comparable results suggesting that either method is useful when investigating psychophysics in animals. The results also show that hens’ critical fusion frequency is considerably higher than that of humans which may account for hens’ inability to recognise images presented on standard computer or television monitors.

year: 2009

title: Analysis of bonded joints for small craft and marine applications

authors: Armeanu, Liviu Eduard

subjects: bonded joint

abstract: This Thesis investigates the possibility of replacing, in small craft and recreative boats, some of the more traditionally made joints (using tabbing) with ones made using structural adhesives (adhesive used where the load applied may cause the separation of the adherends [2]), which have the potential to be quicker to produce and have good fatigue resistance. It also focuses on methods that are available to a small and medium size boatbuilding or boat design company in order to design and produce a general safe, light weight adhesive joint. Several static tests were conducted in order to identify the characteristics of the materials to be joined and the properties of the adhesives investigated. A summary of the analytical theories available in order to determine the characteristics of the joints are presented and compared, and several finite element models have been investigated in order to determine the suitability of this method when using adhesive materials. This Thesis focuses first on Single-Lap joints, not only as a joint, but also as a way to compare the characteristics of the adhesives to be used. Three types of adhesives have been tested, two commercially available (Plexus MA550 and Sikaflex 252) and one commonly found on boatbuilding yards, a mixture of vinyl ester and Epiglass HT120 (a silica based filler). It was found that the Plexus MA550 adhesive performed well across different substrates (aluminium and composites) followed closely in performance by the vinyl ester/filler mixture. Very promising results were obtained when a carrier fabric was used inside the adhesive layer. Secondly, a very common type of joint, the T-joint, has been anti - symmetrically tested. A comparison has been made between a more traditionally produced joint (using a small fillet made from vinyl ester and microballoons based filler and EU-glass tabbing) with a joint produced using a fillet made from the above adhesives. It was found that the results from samples with the fillet using the vinyl ester/filler mixture are the closest to the benchmark samples and it seems to be the best candidate to replace the traditional joint, given the strength, failure mode, price and the availability. The joint using a Sikaflex 252 fillet has shown the most interesting results such that none of the materials forming the joint suffered any visible damage after deformation. The joint using a R20mm Plexus MA550 fillet has benefited from the stiffness and the good adhesion characteristics of the adhesive but in all the tests the panels joined ware damaged earlier than for the benchmark samples.

text: Analysis of bonded joints for small craft and marine applications This Thesis investigates the possibility of replacing, in small craft and recreative boats, some of the more traditionally made joints (using tabbing) with ones made using structural adhesives (adhesive used where the load applied may cause the separation of the adherends [2]), which have the potential to be quicker to produce and have good fatigue resistance. It also focuses on methods that are available to a small and medium size boatbuilding or boat design company in order to design and produce a general safe, light weight adhesive joint. Several static tests were conducted in order to identify the characteristics of the materials to be joined and the properties of the adhesives investigated. A summary of the analytical theories available in order to determine the characteristics of the joints are presented and compared, and several finite element models have been investigated in order to determine the suitability of this method when using adhesive materials. This Thesis focuses first on Single-Lap joints, not only as a joint, but also as a way to compare the characteristics of the adhesives to be used. Three types of adhesives have been tested, two commercially available (Plexus MA550 and Sikaflex 252) and one commonly found on boatbuilding yards, a mixture of vinyl ester and Epiglass HT120 (a silica based filler). It was found that the Plexus MA550 adhesive performed well across different substrates (aluminium and composites) followed closely in performance by the vinyl ester/filler mixture. Very promising results were obtained when a carrier fabric was used inside the adhesive layer. Secondly, a very common type of joint, the T-joint, has been anti - symmetrically tested. A comparison has been made between a more traditionally produced joint (using a small fillet made from vinyl ester and microballoons based filler and EU-glass tabbing) with a joint produced using a fillet made from the above adhesives. It was found that the results from samples with the fillet using the vinyl ester/filler mixture are the closest to the benchmark samples and it seems to be the best candidate to replace the traditional joint, given the strength, failure mode, price and the availability. The joint using a Sikaflex 252 fillet has shown the most interesting results such that none of the materials forming the joint suffered any visible damage after deformation. The joint using a R20mm Plexus MA550 fillet has benefited from the stiffness and the good adhesion characteristics of the adhesive but in all the tests the panels joined ware damaged earlier than for the benchmark samples.

year: 2010

title: Māori leaders wellbeing: A self-determination perspective

authors: Roche, Maree A.

subjects: Positive psychology

abstract: This research draws on interviews with 18 Māori leaders from various leadership positions within business, community, political and marae organisations, to garner an understanding of how their leadership roles interact with their own well-being. Analysis of interviews revealed that crosscultural developments in self-determination theory could be gained by incorporating Māori tikanga and values into a model of well-being for Māori leaders. Largely, the principles of tino rangatiratanga (autonomy and self-determination), mana (respect and influence), whānau (extended family), whakapapa (shared history) and whanaungatanga (kin relations, consultation and engagement), were united into a model of leader well-being. This ensured that mātauranga Māori (Māori knowledge) informed our model of Māori leader well-being, while also drawing on the burgeoning Western research in the area of well-being, specifically self-determination theory. Overall, we find that similarities exist with self-determination theory and Māori tikanga and values. However, in contrast to self-determination theory, autonomy and competence are developed within relationships, which means that ‘others’ underpin Māori leaders’ well-being. From this perspective, we present a view of the psychological and well-being resources that Māori leaders draw on to guide them through complex times.

text: Māori leaders wellbeing: A self-determination perspective This research draws on interviews with 18 Māori leaders from various leadership positions within business, community, political and marae organisations, to garner an understanding of how their leadership roles interact with their own well-being. Analysis of interviews revealed that crosscultural developments in self-determination theory could be gained by incorporating Māori tikanga and values into a model of well-being for Māori leaders. Largely, the principles of tino rangatiratanga (autonomy and self-determination), mana (respect and influence), whānau (extended family), whakapapa (shared history) and whanaungatanga (kin relations, consultation and engagement), were united into a model of leader well-being. This ensured that mātauranga Māori (Māori knowledge) informed our model of Māori leader well-being, while also drawing on the burgeoning Western research in the area of well-being, specifically self-determination theory. Overall, we find that similarities exist with self-determination theory and Māori tikanga and values. However, in contrast to self-determination theory, autonomy and competence are developed within relationships, which means that ‘others’ underpin Māori leaders’ well-being. From this perspective, we present a view of the psychological and well-being resources that Māori leaders draw on to guide them through complex times.

year: 2015