title: WekaPyScript: Classification, regression, and filter schemes for WEKA implemented in Python

authors: Beckham, Christopher J.

subjects: computer science

abstract: WekaPyScript is a package for the machine learning software WEKA that allows learning algorithms and preprocessing methods for classification and regression to be written in Python, as opposed to WEKA’s implementation language, Java. This opens up WEKA to its machine learning and scientific computing ecosystem. Furthermore, due to Python’s minimalist syntax, learning algorithms and preprocessing methods can be prototyped easily and utilised from within WEKA. WekaPyScript works by running a local Python server using the host’s installation of Python; as a result, any libraries installed in the host installation can be leveraged when writing a script for WekaPyScript. Three example scripts (two learning algorithms and one preprocessing method) are presented.

text: WekaPyScript: Classification, regression, and filter schemes for WEKA implemented in Python WekaPyScript is a package for the machine learning software WEKA that allows learning algorithms and preprocessing methods for classification and regression to be written in Python, as opposed to WEKA’s implementation language, Java. This opens up WEKA to its machine learning and scientific computing ecosystem. Furthermore, due to Python’s minimalist syntax, learning algorithms and preprocessing methods can be prototyped easily and utilised from within WEKA. WekaPyScript works by running a local Python server using the host’s installation of Python; as a result, any libraries installed in the host installation can be leveraged when writing a script for WekaPyScript. Three example scripts (two learning algorithms and one preprocessing method) are presented.

year: 2016

title: Hydrodynamic and water quality modelling of the lower kaituna river and maketu estuary

authors: Goodhue, Nigel David

subjects: numerical

abstract: The Maketu Estuary is a shallow intertidal estuary (2.3 km2) located in the Bay of Plenty, North Island, New Zealand. The Kaituna River contributes the largest freshwater flow into the estuary through control gates. Lake Rotoiti and indirectly Lake Rotorua supply the base flow to the Kaituna River, with tributaries along the 50 km reach also significantly contributing to the flow. Water quality within the river is affected by elevated nutrients, faecal coliforms, high oxygen demand and algae concentrations derived from the lakes as well as contributions from tributaries and industrial and urban discharge. Through the use of a coupled hydrodynamic-biogeochemical numerical model ELCOM-CAEDYM, this study aims to examine the nutrient, phytoplankton and hydrodynamics of the Maketu Estuary and lower Kaituna River. 

Water quality and hydrodynamic measurements were sourced from Environment Bay of Plenty's data archives as well as a number of instrument deployments to collect water velocity, tidal elevation and salinity and temperature measurements during the course of this study. Included in the field work was a survey of the lower river and estuary bathymetry.

Model simulations predicted that the maximum residence time in the Maketu Estuary is 1.5 days, occurring in the inner western region.  Residence time in the lower river (mouth to 8.5 km upstream) is in the order of hours although some variations were predicted near the river mouth. Growth rates of four phytoplankton groups where assessed over a 15 day period in January 2004. In the Kaituna River ELCOM-CAEDYM predicted that the community growth rates were small with the exception of a slight increase in biomass of the two freshwater groups in a semi-detached river bend. The increase in the loop was correlated with an increase of residence time. In the estuary, marine diatoms showed the highest growth rates in the western region which is expected to relate to retention time and available nutrients. Dinoflagellates showed the smallest variation in predicted growth rates, most likely due to their broad salinity tolerance. The two freshwater species showed a reduction in abundance when mixed with marine water. A principle limiting factor to phytoplankton growth in both the river and estuary is the low residence time.

A number of scenarios were simulated in the river and estuary by altering the forcing conditions in the model. A simulation of the increased nutrient load associated with the Rotoiti diversion wall revealed that phytoplankton growth in the river and estuary will not be significantly affected. Because of the close proximity of the control gates to the river mouth, a proportion of water drawn through the structure can be marine. By opening the old river channel, model simulations predicted that a reduction in salinity would be possible, however the outcome of complete freshwater is probably not achievable. Increasing the discharge volume from the river into the estuary was also simulated. The results indicated that increasing the freshwater inflow at Fords Cut would reduce the salinity in the estuary while increasing the net (residual) flow towards the estuary mouth. Increasing the flow would also result in a greater range of salinity in regions of the estuary. Changing the inflow location to the historic Papahikahawai Channel also affected the salinity in the estuary. The most significant effect of an inflow at this location was a reduction of the residual currents in the western region of the estuary.

text: Hydrodynamic and water quality modelling of the lower kaituna river and maketu estuary The Maketu Estuary is a shallow intertidal estuary (2.3 km2) located in the Bay of Plenty, North Island, New Zealand. The Kaituna River contributes the largest freshwater flow into the estuary through control gates. Lake Rotoiti and indirectly Lake Rotorua supply the base flow to the Kaituna River, with tributaries along the 50 km reach also significantly contributing to the flow. Water quality within the river is affected by elevated nutrients, faecal coliforms, high oxygen demand and algae concentrations derived from the lakes as well as contributions from tributaries and industrial and urban discharge. Through the use of a coupled hydrodynamic-biogeochemical numerical model ELCOM-CAEDYM, this study aims to examine the nutrient, phytoplankton and hydrodynamics of the Maketu Estuary and lower Kaituna River. 

Water quality and hydrodynamic measurements were sourced from Environment Bay of Plenty's data archives as well as a number of instrument deployments to collect water velocity, tidal elevation and salinity and temperature measurements during the course of this study. Included in the field work was a survey of the lower river and estuary bathymetry.

Model simulations predicted that the maximum residence time in the Maketu Estuary is 1.5 days, occurring in the inner western region.  Residence time in the lower river (mouth to 8.5 km upstream) is in the order of hours although some variations were predicted near the river mouth. Growth rates of four phytoplankton groups where assessed over a 15 day period in January 2004. In the Kaituna River ELCOM-CAEDYM predicted that the community growth rates were small with the exception of a slight increase in biomass of the two freshwater groups in a semi-detached river bend. The increase in the loop was correlated with an increase of residence time. In the estuary, marine diatoms showed the highest growth rates in the western region which is expected to relate to retention time and available nutrients. Dinoflagellates showed the smallest variation in predicted growth rates, most likely due to their broad salinity tolerance. The two freshwater species showed a reduction in abundance when mixed with marine water. A principle limiting factor to phytoplankton growth in both the river and estuary is the low residence time.

A number of scenarios were simulated in the river and estuary by altering the forcing conditions in the model. A simulation of the increased nutrient load associated with the Rotoiti diversion wall revealed that phytoplankton growth in the river and estuary will not be significantly affected. Because of the close proximity of the control gates to the river mouth, a proportion of water drawn through the structure can be marine. By opening the old river channel, model simulations predicted that a reduction in salinity would be possible, however the outcome of complete freshwater is probably not achievable. Increasing the discharge volume from the river into the estuary was also simulated. The results indicated that increasing the freshwater inflow at Fords Cut would reduce the salinity in the estuary while increasing the net (residual) flow towards the estuary mouth. Increasing the flow would also result in a greater range of salinity in regions of the estuary. Changing the inflow location to the historic Papahikahawai Channel also affected the salinity in the estuary. The most significant effect of an inflow at this location was a reduction of the residual currents in the western region of the estuary.

year: 2007

title: Maori sustainable development in the 21st Century: The importance of Maori values, strategic planning and information systems

authors: Harmsworth, Garth

subjects: Development studies

abstract: The term ‘sustainable development’ has been widely used since the latter part of the 20th century. The concept implies economic and social development, economic growth, and environmental responsibility in order to sustain improved standards of living based on economic growth, to achieve some form of social equity, and to manage the environment in a sustainable way. Sustainable development should generally be at a rate that allows future generations to meet their needs without causing degradation of the natural environment, and should avoid economic or social decay. The concept has been debated and criticised by many as being ambiguous, untenable, and difficult to achieve, and frequently labelled part of global capitalism. But the concept provides a challenge to all of us, on how to balance economic, social, and cultural goals, while at the same time safeguarding and responsibly managing the environment for future generations. Attempts by indigenous peoples internationally to achieve sustainable development have been based on holistic approaches and frameworks that seek to balance economic, social, cultural and environmental objectives, and these provide effective models for viable sustainable development approaches. Māori Sustainable Development in Aotearoa-New Zealand is a term often used to describe a pathway to Māori autonomy, self-determination, the building of human and social capacity, as part of a strategic direction to capitalise on opportunities in the 21st century. This paper outlines research undertaken between 1998 and 2002 and funded by the Foundation for Research, Science, and Technology (FRST) in the programme “Māori Sustainable Development in Te Puku o Te Ika”, contract UOWX0005, simply referred to as the MSD programme. It focuses on the importance of determining Māori values, a vision, strategic planning and development of information systems as a holistic framework and process method to achieve Māori sustainable development.

text: Maori sustainable development in the 21st Century: The importance of Maori values, strategic planning and information systems The term ‘sustainable development’ has been widely used since the latter part of the 20th century. The concept implies economic and social development, economic growth, and environmental responsibility in order to sustain improved standards of living based on economic growth, to achieve some form of social equity, and to manage the environment in a sustainable way. Sustainable development should generally be at a rate that allows future generations to meet their needs without causing degradation of the natural environment, and should avoid economic or social decay. The concept has been debated and criticised by many as being ambiguous, untenable, and difficult to achieve, and frequently labelled part of global capitalism. But the concept provides a challenge to all of us, on how to balance economic, social, and cultural goals, while at the same time safeguarding and responsibly managing the environment for future generations. Attempts by indigenous peoples internationally to achieve sustainable development have been based on holistic approaches and frameworks that seek to balance economic, social, cultural and environmental objectives, and these provide effective models for viable sustainable development approaches. Māori Sustainable Development in Aotearoa-New Zealand is a term often used to describe a pathway to Māori autonomy, self-determination, the building of human and social capacity, as part of a strategic direction to capitalise on opportunities in the 21st century. This paper outlines research undertaken between 1998 and 2002 and funded by the Foundation for Research, Science, and Technology (FRST) in the programme “Māori Sustainable Development in Te Puku o Te Ika”, contract UOWX0005, simply referred to as the MSD programme. It focuses on the importance of determining Māori values, a vision, strategic planning and development of information systems as a holistic framework and process method to achieve Māori sustainable development.

year: 2002