title: Heat transfer enhancement for site level indirect heat recovery systems using nanofluids as the intermediate fluid

authors: Tarighaleslami, Amir Hossein

subjects: nanoparticle

abstract: In this paper, implementation of nanofluids as a Heat Transfer Enhancement technique in Process Integration has been studied. A step by step flowchart is introduced and as a case study the effect of replacing water with various nanofluids as the heat transfer media in an industrial Heat Recovery Loop (HRL) has been modelled. Nanofluids are prepared by distributing a nanoparticle through a base fluid such as water, ethylene glycol or oils. Suspended nanoparticles slightly affect the thermal and physical properties of the base fluid. Primarily nanoparticles are added to improve the fluid’s heat transfer characteristics by increasing its Reynolds number and thermal conductivity. HRL system in a large dairy factory in New Zealand has been studied as case study. Results show that by applying various HRL design methods and a nanofluid as an intermediate fluid, an increase in heat recovery is possible without the need for extra heat exchanger area and infrastructure. 1.5 vol.% CuO/water nanofluid has been chosen as an intermediate fluid and by using a constant temperature storage control strategy, heat recovery from liquid–liquid heat exchangers increases between 5% and 9%. The air-side heat transfer coefficient limits the impact of using a nanofluid for the air–liquid exchangers. In other cases, the total available duty from the process stream, such as a condenser, significantly nullifies the heat transfer benefit of using a nano- fluid in a retrofit situation. Alternative to increasing heat recovery, results show that applying a nanofluid in the HRL design phase enables heat exchanger area to decrease significantly for liquid–liquid matches. Results show that the increase in pressure drop and friction factor effects in such a system is negligible

text: Heat transfer enhancement for site level indirect heat recovery systems using nanofluids as the intermediate fluid In this paper, implementation of nanofluids as a Heat Transfer Enhancement technique in Process Integration has been studied. A step by step flowchart is introduced and as a case study the effect of replacing water with various nanofluids as the heat transfer media in an industrial Heat Recovery Loop (HRL) has been modelled. Nanofluids are prepared by distributing a nanoparticle through a base fluid such as water, ethylene glycol or oils. Suspended nanoparticles slightly affect the thermal and physical properties of the base fluid. Primarily nanoparticles are added to improve the fluid’s heat transfer characteristics by increasing its Reynolds number and thermal conductivity. HRL system in a large dairy factory in New Zealand has been studied as case study. Results show that by applying various HRL design methods and a nanofluid as an intermediate fluid, an increase in heat recovery is possible without the need for extra heat exchanger area and infrastructure. 1.5 vol.% CuO/water nanofluid has been chosen as an intermediate fluid and by using a constant temperature storage control strategy, heat recovery from liquid–liquid heat exchangers increases between 5% and 9%. The air-side heat transfer coefficient limits the impact of using a nanofluid for the air–liquid exchangers. In other cases, the total available duty from the process stream, such as a condenser, significantly nullifies the heat transfer benefit of using a nano- fluid in a retrofit situation. Alternative to increasing heat recovery, results show that applying a nanofluid in the HRL design phase enables heat exchanger area to decrease significantly for liquid–liquid matches. Results show that the increase in pressure drop and friction factor effects in such a system is negligible

year: 2016

title: An Analysis of Precision teaching

authors: Pocock, Trudy Louise

subjects: precision teaching

abstract: This research examined three components of precision teaching; charting, timed practices, and performance aims. In the first study beginner skaters performed two roller skating skills, forward crosses and back scissors, with the aim of increasing fluency in these skills using precision teaching methods.  Skaters were told to perform the skills as fast as they could during 1-min practises, aiming at a set performance aim, or goal. After each timing skaters were told how many repetitions they had performed. One group charted back scissors only and the other forward crosses only. The skaters became faster in both skills and charting did not produce faster rates. The improvement seen may have been a direct result of the performance aims. Therefore the second study, using back crosses, compared a fixed, difficult performance aim (complete 50 per minute) for one group and an easier, flexible performance aim (beat your previous sessions' high score) for a second group. After each timing skaters were told how many back crosses they had performed. Performance rates increased similarly for both groups, thus the different performance aims did not have different effects, contrary to the goal-setting literature. A third study investigated this further. Skaters performed forward crosses and back scissors during a baseline condition, where there were no performance aims or feedback. Increases in performance rates for both skills occurred. In a second condition, a performance aim higher than their number of repetitions in the previous condition was set and feedback was given for one skill only. There was an immediate increase in rate of the targeted skill for 3 of the 4 skaters, suggesting that the goal, when given with feedback, influenced the rate at which the skaters performed the skill. In the fourth study, where the effect of feedback and practice was examined more closely, soccer players dribbled a ball in and out of cones. As expected those who took part in eight to ten sessions that were told to do their best (an easy goal) and not given feedback performed this skill faster than those who completed only two sessions with the same conditions. Unexpectedly, they also performed faster than those set a performance aim of beating their previous highest score (a hard goal) and who were given feedback. Methodological issues that may have been responsible for this latter result were addressed in the fifth study. Skaters completing 10 sessions of forward crosses, with feedback and with a performance aim of completing 60 repetitions in one minute (a hard goal), became faster than skaters completing 10 sessions without feedback who were told to do their best. Skaters told to do their best, who completed only three sessions without feedback, did not get faster. These results support those in the goal-setting literature that, hard goals with feedback have more effect than being told to do your best. Overall these studies show that short, timed practices and hard performance aims, or goals, may be effective components of precision teaching while visual feedback from charting may not. Further, precision teaching methods were effective when applied to sporting skills such as those used by roller skaters and soccer players for building fluency of basic skills.

text: An Analysis of Precision teaching This research examined three components of precision teaching; charting, timed practices, and performance aims. In the first study beginner skaters performed two roller skating skills, forward crosses and back scissors, with the aim of increasing fluency in these skills using precision teaching methods.  Skaters were told to perform the skills as fast as they could during 1-min practises, aiming at a set performance aim, or goal. After each timing skaters were told how many repetitions they had performed. One group charted back scissors only and the other forward crosses only. The skaters became faster in both skills and charting did not produce faster rates. The improvement seen may have been a direct result of the performance aims. Therefore the second study, using back crosses, compared a fixed, difficult performance aim (complete 50 per minute) for one group and an easier, flexible performance aim (beat your previous sessions' high score) for a second group. After each timing skaters were told how many back crosses they had performed. Performance rates increased similarly for both groups, thus the different performance aims did not have different effects, contrary to the goal-setting literature. A third study investigated this further. Skaters performed forward crosses and back scissors during a baseline condition, where there were no performance aims or feedback. Increases in performance rates for both skills occurred. In a second condition, a performance aim higher than their number of repetitions in the previous condition was set and feedback was given for one skill only. There was an immediate increase in rate of the targeted skill for 3 of the 4 skaters, suggesting that the goal, when given with feedback, influenced the rate at which the skaters performed the skill. In the fourth study, where the effect of feedback and practice was examined more closely, soccer players dribbled a ball in and out of cones. As expected those who took part in eight to ten sessions that were told to do their best (an easy goal) and not given feedback performed this skill faster than those who completed only two sessions with the same conditions. Unexpectedly, they also performed faster than those set a performance aim of beating their previous highest score (a hard goal) and who were given feedback. Methodological issues that may have been responsible for this latter result were addressed in the fifth study. Skaters completing 10 sessions of forward crosses, with feedback and with a performance aim of completing 60 repetitions in one minute (a hard goal), became faster than skaters completing 10 sessions without feedback who were told to do their best. Skaters told to do their best, who completed only three sessions without feedback, did not get faster. These results support those in the goal-setting literature that, hard goals with feedback have more effect than being told to do your best. Overall these studies show that short, timed practices and hard performance aims, or goals, may be effective components of precision teaching while visual feedback from charting may not. Further, precision teaching methods were effective when applied to sporting skills such as those used by roller skaters and soccer players for building fluency of basic skills.

year: 2006

title: Māori Women and Gambling: Every Day is a War Day!

authors: Morrison, Laurie Elena

subjects: Maori

abstract: This study was concerned with the health implications of new forms of gambling such as casinos, pokie machines and internet gambling for Māori women and their families in Auckland and the Bay of Plenty region of Aotearoa (New Zealand). It set out to discover what culturally appropriate services were available and the extent to which Māori women gamblers were utilising them. The literature documenting Māori perceptions of gambling shows that Māori women gamblers and their partner/whānau members and gambling service providers have been little studied previously.
These goals translated into the following specific aims: 1) to study how Māori women problem gamblers, their partner or whānau members and key informants perceived gambling, what it meant to them and why they did it; 2) to investigate the consequences of gambling for Māori women, whānau and service providers in dealing with the effects of gambling; 3) to report on how these three groups dealt with the effects of gambling; and 4) to discover what helped to bring about positive changes for the three groups.
 All of the aims were achieved. 
A Māori approach (Kaupapa Māori), combined with a naturalistic approach to data collection, was adopted. Qualitative methods are most appropriate to use when working with some Māori, as there is a growing realisation that research with Māori needs to be interactive. A Māori research procedure modelled on the ritual ceremony of encounter (Pōwhiri) provided an appropriate structure for the development and presentation of the research process. The major focus was on the qualitative data obtained from semi-structured interviews in two locations - Rotorua and Auckland. The interviews were conducted with twenty Māori women gamblers, sixteen whānau members including partners and ten interviews with staff involved in services that provided help for problem gamblers. The three interview schedules were based on a number of broad themes and open-ended questions to obtain meaningful descriptive data. The interviews were audio recorded and used to produce transcripts that were then sent back to the participants for feedback. Qualitative data analysis was conducted on the returned documents. 
The findings from this study revealed major impacts of the women's socio-economic, familial and societal circumstances on gambling behaviour and its effects, which are areas of concern for mental health professionals and researchers. The mythical Māori canoes on which Māori voyaged from their place of origin (Hawaiiki) to Aotearoa, the Waka, provided an appropriate metaphor to present the interrelationship between the pull and push factors toward gambling, and its implications for society. This is illustrated as a spinning waka, Te Waka Hūrihuri. On the other hand, Te Waka Māia (courageous) demonstrates the relationships between the variables that help Māori women gamblers to cope and helpful strategies found to assist them to modify or stop their gambling behaviour. It is recommended that the government limit the proliferation of gaming venues and continue to encourage development of emerging Māori services. Moreover, a coordinated approach is essential, as Māori women gamblers, partners and whānau members need to heal together for positive outcomes for Māori health development in Aotearoa. 
The main implication of this study is that a wide range of further research into Māori and gambling is required. Recommendations on ways in which the current delivery of services in Rotorua and Auckland could be improved are:
 	That the Ministry of Health purchase services that establish support groups for Māori people with problem gambling and their whānau, and
 	That non-Māori provider services and organisations support the development of emerging Māori services.
Heeding the outcome of this research should help improve New Zealand's existing health policy and capacity for Māori women's health development. It should also enrich our understanding of the adaptation patterns of Māori whānau member/s, and thus should have implications, not only for Māori health policies, but also relevance for the wider field of international cross-comparative research on indigenous gambling and mental health issues.  Limitations of this study included a small, localised sample that means the findings can only tentatively be generalised to the wider population of Māori women gamblers. Nonetheless, information gained from the study contributes to understanding of the adaptation patterns of Māori women gamblers, their whānau member/s, and those who are trying to help them.  It is hoped that the study will make it at least a little less true that  every day is a war day  for Māori women and their whānau trying to deal with the problem of gambling.

text: Māori Women and Gambling: Every Day is a War Day! This study was concerned with the health implications of new forms of gambling such as casinos, pokie machines and internet gambling for Māori women and their families in Auckland and the Bay of Plenty region of Aotearoa (New Zealand). It set out to discover what culturally appropriate services were available and the extent to which Māori women gamblers were utilising them. The literature documenting Māori perceptions of gambling shows that Māori women gamblers and their partner/whānau members and gambling service providers have been little studied previously.
These goals translated into the following specific aims: 1) to study how Māori women problem gamblers, their partner or whānau members and key informants perceived gambling, what it meant to them and why they did it; 2) to investigate the consequences of gambling for Māori women, whānau and service providers in dealing with the effects of gambling; 3) to report on how these three groups dealt with the effects of gambling; and 4) to discover what helped to bring about positive changes for the three groups.
 All of the aims were achieved. 
A Māori approach (Kaupapa Māori), combined with a naturalistic approach to data collection, was adopted. Qualitative methods are most appropriate to use when working with some Māori, as there is a growing realisation that research with Māori needs to be interactive. A Māori research procedure modelled on the ritual ceremony of encounter (Pōwhiri) provided an appropriate structure for the development and presentation of the research process. The major focus was on the qualitative data obtained from semi-structured interviews in two locations - Rotorua and Auckland. The interviews were conducted with twenty Māori women gamblers, sixteen whānau members including partners and ten interviews with staff involved in services that provided help for problem gamblers. The three interview schedules were based on a number of broad themes and open-ended questions to obtain meaningful descriptive data. The interviews were audio recorded and used to produce transcripts that were then sent back to the participants for feedback. Qualitative data analysis was conducted on the returned documents. 
The findings from this study revealed major impacts of the women's socio-economic, familial and societal circumstances on gambling behaviour and its effects, which are areas of concern for mental health professionals and researchers. The mythical Māori canoes on which Māori voyaged from their place of origin (Hawaiiki) to Aotearoa, the Waka, provided an appropriate metaphor to present the interrelationship between the pull and push factors toward gambling, and its implications for society. This is illustrated as a spinning waka, Te Waka Hūrihuri. On the other hand, Te Waka Māia (courageous) demonstrates the relationships between the variables that help Māori women gamblers to cope and helpful strategies found to assist them to modify or stop their gambling behaviour. It is recommended that the government limit the proliferation of gaming venues and continue to encourage development of emerging Māori services. Moreover, a coordinated approach is essential, as Māori women gamblers, partners and whānau members need to heal together for positive outcomes for Māori health development in Aotearoa. 
The main implication of this study is that a wide range of further research into Māori and gambling is required. Recommendations on ways in which the current delivery of services in Rotorua and Auckland could be improved are:
 	That the Ministry of Health purchase services that establish support groups for Māori people with problem gambling and their whānau, and
 	That non-Māori provider services and organisations support the development of emerging Māori services.
Heeding the outcome of this research should help improve New Zealand's existing health policy and capacity for Māori women's health development. It should also enrich our understanding of the adaptation patterns of Māori whānau member/s, and thus should have implications, not only for Māori health policies, but also relevance for the wider field of international cross-comparative research on indigenous gambling and mental health issues.  Limitations of this study included a small, localised sample that means the findings can only tentatively be generalised to the wider population of Māori women gamblers. Nonetheless, information gained from the study contributes to understanding of the adaptation patterns of Māori women gamblers, their whānau member/s, and those who are trying to help them.  It is hoped that the study will make it at least a little less true that  every day is a war day  for Māori women and their whānau trying to deal with the problem of gambling.

year: 2008