title: Positive and negative penalty parameters in optimisation subjected to continuous constraints

authors: Ilanko, Sinniah

subjects: curve fitting

abstract: In solving variational, differential and optimisation equations subject to constraints, the penalty method is a well known procedure. Recent publications show that with a combination of positive and negative penalty parameters, constraint violations can be determined and controlled. This relies on the monotonic nature of convergence of the penalised model towards the constrained system, which has been proven and demonstrated for systems with discrete constraints. This paper investigates the use of this approach for systems with continuous constraints. It addresses the questions of whether the number of critical penalty parameters for continuous constraints is finite, and whether the positive and negative penalty method result in monotonic and bounded convergence towards the constrained solution, and compares the use of penalty functions in integral form and discrete forms to represent continuous constraints.

text: Positive and negative penalty parameters in optimisation subjected to continuous constraints In solving variational, differential and optimisation equations subject to constraints, the penalty method is a well known procedure. Recent publications show that with a combination of positive and negative penalty parameters, constraint violations can be determined and controlled. This relies on the monotonic nature of convergence of the penalised model towards the constrained system, which has been proven and demonstrated for systems with discrete constraints. This paper investigates the use of this approach for systems with continuous constraints. It addresses the questions of whether the number of critical penalty parameters for continuous constraints is finite, and whether the positive and negative penalty method result in monotonic and bounded convergence towards the constrained solution, and compares the use of penalty functions in integral form and discrete forms to represent continuous constraints.

year: 2012

title: Assessing vulnerability of New Zealand lakes to loss of conservation value from invasive fish impacts

authors: Collier, Kevin J.

subjects: lake

abstract: 1. Predictions of invasion risk for seven non-indigenous fish species, ecological impact scores for individual species, and lake conservation rankings were linked to develop Invasion Risk Impact (IRI) and Lake Vulnerability (LV) indices that help identify New Zealand lakes most at risk of loss of conservation value from potential multi-species invasions.
2. Species-specific IRI scores (the product of predicted invasion risk and species impact) highlighted Eurasian perch (Perca fluviatilis) and the brown bullhead (Ameiurus nebulosus), as the species most likely to spread and cause ecological harm in lakes. For 3431 lakes >1 ha throughout New Zealand, total IRI tended to be highest for lowland riverine and dune lakes most of which are already colonized by multiple invasive fish species.
3. The LV index indicated that lakes most at risk of loss of conservation value from invasive fish impacts were predominantly (i) in the northern half of the North Island where several uncommon lake types occur, and (ii) along the west coast of the South Island where conservation value is often greater, largely because of low catchment modification.
4. The IRI and LV indices can be used to assist with setting priorities for surveillance monitoring, advocacy, and response planning targeted at preventing the establishment of invasive fish in moderate-to-high value lakes most susceptible to ecological impacts. Both indices can be adapted to accommodate alternative impact and conservation scoring systems, providing a flexible tool for local- and national-scale assessments of lake vulnerability to fish invasion impacts.

text: Assessing vulnerability of New Zealand lakes to loss of conservation value from invasive fish impacts 1. Predictions of invasion risk for seven non-indigenous fish species, ecological impact scores for individual species, and lake conservation rankings were linked to develop Invasion Risk Impact (IRI) and Lake Vulnerability (LV) indices that help identify New Zealand lakes most at risk of loss of conservation value from potential multi-species invasions.
2. Species-specific IRI scores (the product of predicted invasion risk and species impact) highlighted Eurasian perch (Perca fluviatilis) and the brown bullhead (Ameiurus nebulosus), as the species most likely to spread and cause ecological harm in lakes. For 3431 lakes >1 ha throughout New Zealand, total IRI tended to be highest for lowland riverine and dune lakes most of which are already colonized by multiple invasive fish species.
3. The LV index indicated that lakes most at risk of loss of conservation value from invasive fish impacts were predominantly (i) in the northern half of the North Island where several uncommon lake types occur, and (ii) along the west coast of the South Island where conservation value is often greater, largely because of low catchment modification.
4. The IRI and LV indices can be used to assist with setting priorities for surveillance monitoring, advocacy, and response planning targeted at preventing the establishment of invasive fish in moderate-to-high value lakes most susceptible to ecological impacts. Both indices can be adapted to accommodate alternative impact and conservation scoring systems, providing a flexible tool for local- and national-scale assessments of lake vulnerability to fish invasion impacts.

year: 2016

title: Tā Pikitia Hei Āwhina Kōrero  Collaborative Drawing and Storying

authors: Kururangi, Aorere Helen Mary

subjects: collaborative drawing and storying

abstract: Creating a Māori medium context for beginning learners of te reo Māori to converse in genuine dialogue, was a real challenge for our mainstream bilingual unit. This study involved six Year 3-5 primary school students working in two groups of three. The bilingual unit is in a contributing school in an urban setting.

The teacher, a second language learner herself, found students seldom initiated any spontaneous Māori dialogue and tended to respond only to questions or formal teacher initiated direction. So the project sought to develop and explore the approach Tā Pikitia hei āwhina kōrero or Collaborative Drawing and Storying, to improve Children's Oral Language Acquisition in Māori, using a socially responsive approach (Glynn, Wearmouth,  Berryman, 2006)
 
This method encouraged students to initiate, respond and share their own learning in a social and interactive community of learners. The method also allowed students the freedom to generate conversations about their own interests, ideas and background experiences without teacher intervention or direction. The only requirement was me kōrero Māori i nga wā katoa (speak Māori all the time). A collaborative picture was created as each group of students quickly illustrated their ideas on a large piece of paper.

 Each student was pre tested and post tested using the Aromatawai Reo A Waha  - Kia Tere Tonu  (Berryman  Langdon, 2001).This test assessed each student's Māori vocabulary knowledge and their ability to speak spontaneously about a familiar item. The daily conversations created by each student group involved Tā Pikitia hei āwhina  kōrero was recorded on tape, then transcribed verbatim each day to assess changes over time. 

 Student ownership of the learning and their positive participation resulted in improved language outcomes. At the end of the ten week period there were encouraging gains in the post test, Aromatawai Reo A Waha - Kīanga or spontaneous phrases students were able to generate. Furthermore an improved ability to focus on an oral task, and improved engagement by the students were unexpected positive outcomes of this easy to implement activity.

text: Tā Pikitia Hei Āwhina Kōrero  Collaborative Drawing and Storying Creating a Māori medium context for beginning learners of te reo Māori to converse in genuine dialogue, was a real challenge for our mainstream bilingual unit. This study involved six Year 3-5 primary school students working in two groups of three. The bilingual unit is in a contributing school in an urban setting.

The teacher, a second language learner herself, found students seldom initiated any spontaneous Māori dialogue and tended to respond only to questions or formal teacher initiated direction. So the project sought to develop and explore the approach Tā Pikitia hei āwhina kōrero or Collaborative Drawing and Storying, to improve Children's Oral Language Acquisition in Māori, using a socially responsive approach (Glynn, Wearmouth,  Berryman, 2006)
 
This method encouraged students to initiate, respond and share their own learning in a social and interactive community of learners. The method also allowed students the freedom to generate conversations about their own interests, ideas and background experiences without teacher intervention or direction. The only requirement was me kōrero Māori i nga wā katoa (speak Māori all the time). A collaborative picture was created as each group of students quickly illustrated their ideas on a large piece of paper.

 Each student was pre tested and post tested using the Aromatawai Reo A Waha  - Kia Tere Tonu  (Berryman  Langdon, 2001).This test assessed each student's Māori vocabulary knowledge and their ability to speak spontaneously about a familiar item. The daily conversations created by each student group involved Tā Pikitia hei āwhina  kōrero was recorded on tape, then transcribed verbatim each day to assess changes over time. 

 Student ownership of the learning and their positive participation resulted in improved language outcomes. At the end of the ten week period there were encouraging gains in the post test, Aromatawai Reo A Waha - Kīanga or spontaneous phrases students were able to generate. Furthermore an improved ability to focus on an oral task, and improved engagement by the students were unexpected positive outcomes of this easy to implement activity.

year: 2008