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: Production outsourcing offshore in the New Zealand printing, publishing and packaging industries

authors: Skiffington, Hayden

subjects: offshore outsourcing

abstract: Purpose – The study aims to investigate the production offshore outsourcing practices of SMEs in the New Zealand printing, publishing and packaging industries. It identifies the techniques SMEs use to organise and manage their offshore outsourcing activities. The authors then develop a managerial framework to assist SMEs in their future offshore outsourcing ambitions.

Design/methodology/approach – The study takes a qualitative approach; obtaining data from a sample of 22 New Zealand SMEs in the printing, publishing and packaging industries that are actively offshore outsourcing production tasks. Data was gathered in the form of semi-structured interviews with SME managers who have carried out offshore outsourcing.

Findings – To mitigate offshore outsourcing costs, SMEs use the internet to locate suppliers and use short-term reliable contracts that are managed remotely or by intermediaries. Customer involvement was highly important during the entire offshore outsourcing process. Most SMEs developed long-term business relationships with reliable suppliers. These findings are integrated into the SME framework, which identifies ways SMEs can overcome resource constraints and minimise risks when offshore outsourcing.

Research limitations/implications – This study is confined to a single country and reports on findings for several related industries, i.e. the printing, publishing and packaging industries in New Zealand. This limits its applicability to research in other settings and other industries. However, it identifies an area of research (offshore outsourcing activities in SMEs) that could be extended to other industries and countries by future research.

Practical implications – The SME framework presents an easily understood approach that has been verified by SME managers who have successfully offshore outsourced production tasks. The research proves that SMEs can offshore outsource within the constraints of limited physical and managerial resources.

Social implications – The study showed that the decision-making process to outsource is supported by the transaction costs approach. Firms have to balance out total cost considerations in making their decision to offshore (including contingency costs) to ensure that the savings from outsourcing are greater than the transaction costs. The resource-based view of the firm is also used to suggest that offshore outsourcing means that firms may be able to improve their own competences by providing (through their suppliers) access to more sophisticated and higher-quality processes.

Originality/value – The research contributes to the growing area of SME offshore outsourcing research, providing detailed empirical evidence of SME offshore outsourcing activities occurring in New Zealand.

text: Production outsourcing offshore in the New Zealand printing, publishing and packaging industries Purpose – The study aims to investigate the production offshore outsourcing practices of SMEs in the New Zealand printing, publishing and packaging industries. It identifies the techniques SMEs use to organise and manage their offshore outsourcing activities. The authors then develop a managerial framework to assist SMEs in their future offshore outsourcing ambitions.

Design/methodology/approach – The study takes a qualitative approach; obtaining data from a sample of 22 New Zealand SMEs in the printing, publishing and packaging industries that are actively offshore outsourcing production tasks. Data was gathered in the form of semi-structured interviews with SME managers who have carried out offshore outsourcing.

Findings – To mitigate offshore outsourcing costs, SMEs use the internet to locate suppliers and use short-term reliable contracts that are managed remotely or by intermediaries. Customer involvement was highly important during the entire offshore outsourcing process. Most SMEs developed long-term business relationships with reliable suppliers. These findings are integrated into the SME framework, which identifies ways SMEs can overcome resource constraints and minimise risks when offshore outsourcing.

Research limitations/implications – This study is confined to a single country and reports on findings for several related industries, i.e. the printing, publishing and packaging industries in New Zealand. This limits its applicability to research in other settings and other industries. However, it identifies an area of research (offshore outsourcing activities in SMEs) that could be extended to other industries and countries by future research.

Practical implications – The SME framework presents an easily understood approach that has been verified by SME managers who have successfully offshore outsourced production tasks. The research proves that SMEs can offshore outsource within the constraints of limited physical and managerial resources.

Social implications – The study showed that the decision-making process to outsource is supported by the transaction costs approach. Firms have to balance out total cost considerations in making their decision to offshore (including contingency costs) to ensure that the savings from outsourcing are greater than the transaction costs. The resource-based view of the firm is also used to suggest that offshore outsourcing means that firms may be able to improve their own competences by providing (through their suppliers) access to more sophisticated and higher-quality processes.

Originality/value – The research contributes to the growing area of SME offshore outsourcing research, providing detailed empirical evidence of SME offshore outsourcing activities occurring in New Zealand.

year: 2013

title: Toitu Te Moananui a Toi – The Effects of the MV Rena on the Water Quality, Chemistry and Zooplankton of Otaiti (Astrolabe Reef)

authors: Dempsey, Te Puea Toni

subjects: metal contamination

abstract: Humans have had a profound effect on the world’s oceans, particularly through pollution. Marine pollution incidents are particularly important and increasingly involve both petrochemical and metal contamination. The effects of complex high level, point source pollution events such as ship wrecks on larval recruitment to reef environments is not well understood. Larval settlement is heavily influenced by chemical cues, hence pollution events could have a long term influence on reef ecology, and the likelihood that planktonic zooplankton can entrain contaminants into the reef food web is also of concern.
This thesis aims to address concerns from local Tangata Whenua, government, researchers, stakeholders and the public about the long term recovery of Otaiti following the MV Rena shipwreck and subsequent reef contamination. The incident is a complex one involving metallic container debris contamination along with oil. Research focussed on assessing the effects of water borne contamination surrounding the wreck site in order to examine acute and chronic responses of planktonic invertebrates: (1) the influence of Rena and associated debris to the chemistry and quality of water in the benthic zone around the wreck, (2) the toxicity of contaminants to survivorship of zooplankton, and (3) the influence on contaminant plumes to zooplankton recruitment behaviour of Otaiti.
There is a clear effect from the Rena and its associated debris field on the water quality and chemistry of Otaiti. Aluminium and copper for example, were consistently elevated in dissolved and total metal concentrations around the debris field. Laboratory based exposure of zooplankton to realistic concentration gradients of Rena contaminated sediments resulted in increased mortality with increased contaminant concentrations. Behavioural responses of pelagic and settling invertebrates to Rena pollution influenced sediment highlighted sensitivity to associated contaminant plumes. This could have significant ecological implications to the recruitment behaviour of other planktonic organisms that rely on reef conspecifics and chemical cues to initiate settlement.
Ecological concepts such as ecosystem function and biodiversity dynamics (including recruitment) relate the life force and longevity of a system. Key concerns within the scope of this research were highlighted that may have implications to Tangata Whenua decision making in assessing the Mauri of Otaiti. It can be implied that the Rena continues to impact the Mauri of Otaiti due to the presence of contaminants within the debris field.

text: Toitu Te Moananui a Toi – The Effects of the MV Rena on the Water Quality, Chemistry and Zooplankton of Otaiti (Astrolabe Reef) Humans have had a profound effect on the world’s oceans, particularly through pollution. Marine pollution incidents are particularly important and increasingly involve both petrochemical and metal contamination. The effects of complex high level, point source pollution events such as ship wrecks on larval recruitment to reef environments is not well understood. Larval settlement is heavily influenced by chemical cues, hence pollution events could have a long term influence on reef ecology, and the likelihood that planktonic zooplankton can entrain contaminants into the reef food web is also of concern.
This thesis aims to address concerns from local Tangata Whenua, government, researchers, stakeholders and the public about the long term recovery of Otaiti following the MV Rena shipwreck and subsequent reef contamination. The incident is a complex one involving metallic container debris contamination along with oil. Research focussed on assessing the effects of water borne contamination surrounding the wreck site in order to examine acute and chronic responses of planktonic invertebrates: (1) the influence of Rena and associated debris to the chemistry and quality of water in the benthic zone around the wreck, (2) the toxicity of contaminants to survivorship of zooplankton, and (3) the influence on contaminant plumes to zooplankton recruitment behaviour of Otaiti.
There is a clear effect from the Rena and its associated debris field on the water quality and chemistry of Otaiti. Aluminium and copper for example, were consistently elevated in dissolved and total metal concentrations around the debris field. Laboratory based exposure of zooplankton to realistic concentration gradients of Rena contaminated sediments resulted in increased mortality with increased contaminant concentrations. Behavioural responses of pelagic and settling invertebrates to Rena pollution influenced sediment highlighted sensitivity to associated contaminant plumes. This could have significant ecological implications to the recruitment behaviour of other planktonic organisms that rely on reef conspecifics and chemical cues to initiate settlement.
Ecological concepts such as ecosystem function and biodiversity dynamics (including recruitment) relate the life force and longevity of a system. Key concerns within the scope of this research were highlighted that may have implications to Tangata Whenua decision making in assessing the Mauri of Otaiti. It can be implied that the Rena continues to impact the Mauri of Otaiti due to the presence of contaminants within the debris field.

year: 2015