title: Choosing the right microcontroller: A comparison of 8-bit Atmel, Microchip and Freescale MCUs

authors: Slade, Mel

subjects: engineering

abstract: When choosing a microcontroller there are many options, so which platform should you choose? There is little independent information available to help engineers decide which platform might best suit their needs and most designers tend to stick with the brand with which they are familiar. This is a difficult question to answer without bias if the people
conducting the evaluations have had previous experience with MCU programming predominantly on one platform. This article draws on a case study. We built three “Smart” Sprinkler Taps, small, self-contained irrigation controllers, differing only in the microcontroller unit (MCU) on the inside. We compare cost, development software quality and hardware performance from the perspective of a new user to each of the platforms.

text: Choosing the right microcontroller: A comparison of 8-bit Atmel, Microchip and Freescale MCUs When choosing a microcontroller there are many options, so which platform should you choose? There is little independent information available to help engineers decide which platform might best suit their needs and most designers tend to stick with the brand with which they are familiar. This is a difficult question to answer without bias if the people
conducting the evaluations have had previous experience with MCU programming predominantly on one platform. This article draws on a case study. We built three “Smart” Sprinkler Taps, small, self-contained irrigation controllers, differing only in the microcontroller unit (MCU) on the inside. We compare cost, development software quality and hardware performance from the perspective of a new user to each of the platforms.

year: 2011-11

title: Electromyographic assessment of pullover exercise variations and javelin throw on nine upper-body muscles

authors: Washif, Jad Adrian

abstract: Exercise choice is one important variable for attaining athletic training aims. Pullover exercises are integrated into resistance training programs of javelin throwers to develop event-specific strength. We examined the electromyography (EMG) signals during four pullover exercise variations: conventional (CONV), straight-arm (STR), bent-arm (BENT), and conventional on unstable surface (UNS); and javelin throwing (JAVT) using an 800 g standard implement. Generally, BENT elicited the highest peak activity of all muscles (22-89% MVC), except for the rectus abdominus which was highest during UNS (106%). In contrast, CONV tended to produce the lowest peak muscle activation (12-77%), except for the pectoral and middle deltoid muscles. It was noteworthy that despite being the same exercise, performance on the unstable surface elicited higher peak muscle activity than CONV, except from the pectoralis muscles. Peak muscle activation in JAVT ranged from 29 (posterior deltoid) to 124% (latissimus dorsi), with the relatively high peaks in the deltoids and latissimus dorsi not being matched during the pullover exercises. Surface EMG of five national male javelin throwers were recorded from nine muscles on the throwing-arm side: upper trapezius; anterior, middle, and posterior deltoid; triceps brachii; clavicular and sternal portions of pectoralis major; latissimus dorsi, and rectus abdominus. In a randomised fashion, all throwers performed six repetitions of each pullover variation using a free-weight curl-barbell against an external load at 85% of 1-repetition maximum, while EMG signals were recorded during both the concentric and eccentric phases of the movement and subsequently normalized to a maximal voluntary contraction (MVC). The throwers then performed three maximal javelin throws and the one with the greatest throwing velocity was used for analysis. It has been noted that pullover exercise emphasize chest muscle activation, i.e. pectoralis major (Marchetti & Uchida, 2011). Here, the level of activation depended on pullover variation, and BENT elicited the highest overall peak muscle activity. Strength and conditioning specialists should be aware of the impact of different pullover variations on muscle activation levels, and note that additional exercises to target the musculature of the shoulder and upper back should be incorporated in the training of javelin throwers.

text: Electromyographic assessment of pullover exercise variations and javelin throw on nine upper-body muscles Exercise choice is one important variable for attaining athletic training aims. Pullover exercises are integrated into resistance training programs of javelin throwers to develop event-specific strength. We examined the electromyography (EMG) signals during four pullover exercise variations: conventional (CONV), straight-arm (STR), bent-arm (BENT), and conventional on unstable surface (UNS); and javelin throwing (JAVT) using an 800 g standard implement. Generally, BENT elicited the highest peak activity of all muscles (22-89% MVC), except for the rectus abdominus which was highest during UNS (106%). In contrast, CONV tended to produce the lowest peak muscle activation (12-77%), except for the pectoral and middle deltoid muscles. It was noteworthy that despite being the same exercise, performance on the unstable surface elicited higher peak muscle activity than CONV, except from the pectoralis muscles. Peak muscle activation in JAVT ranged from 29 (posterior deltoid) to 124% (latissimus dorsi), with the relatively high peaks in the deltoids and latissimus dorsi not being matched during the pullover exercises. Surface EMG of five national male javelin throwers were recorded from nine muscles on the throwing-arm side: upper trapezius; anterior, middle, and posterior deltoid; triceps brachii; clavicular and sternal portions of pectoralis major; latissimus dorsi, and rectus abdominus. In a randomised fashion, all throwers performed six repetitions of each pullover variation using a free-weight curl-barbell against an external load at 85% of 1-repetition maximum, while EMG signals were recorded during both the concentric and eccentric phases of the movement and subsequently normalized to a maximal voluntary contraction (MVC). The throwers then performed three maximal javelin throws and the one with the greatest throwing velocity was used for analysis. It has been noted that pullover exercise emphasize chest muscle activation, i.e. pectoralis major (Marchetti & Uchida, 2011). Here, the level of activation depended on pullover variation, and BENT elicited the highest overall peak muscle activity. Strength and conditioning specialists should be aware of the impact of different pullover variations on muscle activation levels, and note that additional exercises to target the musculature of the shoulder and upper back should be incorporated in the training of javelin throwers.

year: 2016

title: The Determinants of Tribal Population Growth in the New Zealand Census

authors: Rarere, Moana

subjects: tribal population growth

abstract: By the early twentieth century the notion that ethnic populations would dissipate was a commonly held belief.  However, after World War II, the modern world has seen an incredible resurgence in ethnic identities.  Ethnic conflicts, mobilisations, and the political movements of the 1950s and 1960s served as a major catalyst in the diffusion of indigenous identities and rights.  Consequently, indigenous groups in settler states, especially in North America, experienced population growth beyond the levels of natural demographic factors, that is, fertility, mortality and migration.  Researchers attributed a significant proportion of this growth to changing patterns of ethnic identification, also referred to as ethnic mobility .  Although this phenomenon is well documented in North America, it is only just beginning to be understood in relation to the New Zealand context. 

During the 1970s and 1980s, the indigenous Māori population of New Zealand gained substantial progress in political, social and economic spheres, following the same patterns of ethnic identity growth as in North America.  Despite these gains, the average individual socio-economic outcomes for Māori remain poor, especially in comparison to New Zealand Europeans/Pākehā.  Through key legislation, iwi (tribal) organisations became the core mechanism in which to address Māori socio-economic issues, achieve Māori aspirations and to manage Treaty of Waitangi settlement monies.  Subsequently, the need for iwi statistics for policy and planning purposes saw the reinstatement of iwi data in the New Zealand census in 1991.  Surprisingly, however, very little attention has been given to contemporary patterns of iwi demography.

Since the 1991 census, observations of total iwi population growth patterns indicate these patterns cannot solely be explained by natural demographic factors.  Furthermore, the growth trajectories of individual iwi were markedly different, and in some cases erratic.  These initial observations have raised the following key research questions: What do patterns of iwi growth look like?  What is the role of ethnic mobility?  What factors drive ethnic mobility?  Who changes iwi identification?  Why should we care?  

This thesis examines patterns of iwi identification in the New Zealand Census of Population and Dwellings from 1991 to 2006.  It uses statistical methods to not only document iwi population changes but to also identify the key determinants driving these trajectories.  In addition, this thesis considers ethnic mobility as an important driver of population growth but, situates this within the broader macro-political environment.  Along with the analysis of aggregate iwi population changes, this thesis also provides an in-depth analysis of four iwi groups – Ngāi Tahu, Waikato, Ngāti Awa and Tūhoe, in order to observe individual iwi dynamics that are not clearly visible at the aggregate level.

The findings of this thesis raise important implications for theories of ethnicity and the demographic study of ethnic populations.  For example, this thesis argues that the category of ethnic mobility is mainly contextual, that is, decisions to change ethnic responses are influenced by the broader political, social and economic contexts.  Furthermore this thesis contends that individual ethnic identification decisions are for the most part defined by ethnic categories imposed by the State.  While traditional views suggest ethnicity is fixed, intrinsic and kinship based, this thesis finds significant support for contemporary views that argue ethnicity is fluid, extrinsic and socially constructed.  Rather than reject traditional views of Maori identity, this study recognises that ethnic identities are complex, and that shifts in iwi identification is about connecting and reconnecting with whakapapa.  Thus this thesis argues that in order to understand individual iwi dynamics both points of view need to be considered.

text: The Determinants of Tribal Population Growth in the New Zealand Census By the early twentieth century the notion that ethnic populations would dissipate was a commonly held belief.  However, after World War II, the modern world has seen an incredible resurgence in ethnic identities.  Ethnic conflicts, mobilisations, and the political movements of the 1950s and 1960s served as a major catalyst in the diffusion of indigenous identities and rights.  Consequently, indigenous groups in settler states, especially in North America, experienced population growth beyond the levels of natural demographic factors, that is, fertility, mortality and migration.  Researchers attributed a significant proportion of this growth to changing patterns of ethnic identification, also referred to as ethnic mobility .  Although this phenomenon is well documented in North America, it is only just beginning to be understood in relation to the New Zealand context. 

During the 1970s and 1980s, the indigenous Māori population of New Zealand gained substantial progress in political, social and economic spheres, following the same patterns of ethnic identity growth as in North America.  Despite these gains, the average individual socio-economic outcomes for Māori remain poor, especially in comparison to New Zealand Europeans/Pākehā.  Through key legislation, iwi (tribal) organisations became the core mechanism in which to address Māori socio-economic issues, achieve Māori aspirations and to manage Treaty of Waitangi settlement monies.  Subsequently, the need for iwi statistics for policy and planning purposes saw the reinstatement of iwi data in the New Zealand census in 1991.  Surprisingly, however, very little attention has been given to contemporary patterns of iwi demography.

Since the 1991 census, observations of total iwi population growth patterns indicate these patterns cannot solely be explained by natural demographic factors.  Furthermore, the growth trajectories of individual iwi were markedly different, and in some cases erratic.  These initial observations have raised the following key research questions: What do patterns of iwi growth look like?  What is the role of ethnic mobility?  What factors drive ethnic mobility?  Who changes iwi identification?  Why should we care?  

This thesis examines patterns of iwi identification in the New Zealand Census of Population and Dwellings from 1991 to 2006.  It uses statistical methods to not only document iwi population changes but to also identify the key determinants driving these trajectories.  In addition, this thesis considers ethnic mobility as an important driver of population growth but, situates this within the broader macro-political environment.  Along with the analysis of aggregate iwi population changes, this thesis also provides an in-depth analysis of four iwi groups – Ngāi Tahu, Waikato, Ngāti Awa and Tūhoe, in order to observe individual iwi dynamics that are not clearly visible at the aggregate level.

The findings of this thesis raise important implications for theories of ethnicity and the demographic study of ethnic populations.  For example, this thesis argues that the category of ethnic mobility is mainly contextual, that is, decisions to change ethnic responses are influenced by the broader political, social and economic contexts.  Furthermore this thesis contends that individual ethnic identification decisions are for the most part defined by ethnic categories imposed by the State.  While traditional views suggest ethnicity is fixed, intrinsic and kinship based, this thesis finds significant support for contemporary views that argue ethnicity is fluid, extrinsic and socially constructed.  Rather than reject traditional views of Maori identity, this study recognises that ethnic identities are complex, and that shifts in iwi identification is about connecting and reconnecting with whakapapa.  Thus this thesis argues that in order to understand individual iwi dynamics both points of view need to be considered.

year: 2012