title: Comparison between the RSA cryptosystem and elliptic curve cryptography

authors: Abdullah, Kamilah

subjects: Cryptography

abstract: In the globalization era, cryptography becomes more popular and powerful; in fact it is very important in many areas (i.e. mathematics, computer science, networks, etc). This thesis provides an overview and comparison between the
RSA cryptosystem and elliptic curve cryptography, which both focus on sending and receiving messages. The basic theories of the RSA cryptosystem and elliptic curve cryptography are explored. The RSA cryptosystem and elliptic
curve cryptography theories are quite similar but elliptic curve cryptography is more complicated. The idea of the RSA cryptosystem is based on three
popular theorems which are Euler's Theorem, Fermat's Little Theorem and the Chinese Remainder Theorem. This discussion shows that the reliability and strong security of the RSA cryptosystem depends on the degree of dif-
ficulty of integer factorization. Therefore, methods for integer factorization are discussed. In addition I show how the security of elliptic curve cryptography depends on the apparent difficulty of solving the elliptic curve discrete
logarithm problem (ECDLP).

text: Comparison between the RSA cryptosystem and elliptic curve cryptography In the globalization era, cryptography becomes more popular and powerful; in fact it is very important in many areas (i.e. mathematics, computer science, networks, etc). This thesis provides an overview and comparison between the
RSA cryptosystem and elliptic curve cryptography, which both focus on sending and receiving messages. The basic theories of the RSA cryptosystem and elliptic curve cryptography are explored. The RSA cryptosystem and elliptic
curve cryptography theories are quite similar but elliptic curve cryptography is more complicated. The idea of the RSA cryptosystem is based on three
popular theorems which are Euler's Theorem, Fermat's Little Theorem and the Chinese Remainder Theorem. This discussion shows that the reliability and strong security of the RSA cryptosystem depends on the degree of dif-
ficulty of integer factorization. Therefore, methods for integer factorization are discussed. In addition I show how the security of elliptic curve cryptography depends on the apparent difficulty of solving the elliptic curve discrete
logarithm problem (ECDLP).

year: 2010

title: Surgical treatment of early stage breast cancer in the Auckland and Waikato regions of New Zealand

authors: Campbell, Ian

subjects: Science & Technology

abstract: Background
The aim of this study was to understand the factors influencing the use of surgical options by New Zealand women with newly diagnosed breast cancer.

Methods
Using data from the Auckland and Waikato breast cancer registers, we included 11 798 women diagnosed with stage I–III breast cancer from June 2000 to May 2013. The characteristics of women receiving different surgical treatments and having immediate breast reconstruction following mastectomy were examined. A logistic regression was used to estimate the odds ratio of having breast‐conserving surgery (BCS) versus mastectomy and immediate post‐mastectomy reconstruction. Bilateral breast cancer cases and women with unilateral breast cancer, but who had bilateral surgery, were also identified.

Results
Fifty‐two percent of women received BCS and 44% had mastectomy over the study period. Key influences associated with BCS were age, mode of diagnosis, socio‐economic status and public or private treatment. Just under half of the women who underwent bilateral surgery did not have bilateral cancer. Nineteen percent of women undergoing mastectomy underwent immediate reconstruction. Implant use increased slightly over the study period but there was a decrease in the use of autologous flap procedures.

Conclusion
Surgical management of women with localized breast cancer was generally in line with guidelines, but with potential to further increase the use of breast conservation and immediate reconstruction in suitable cases.

text: Surgical treatment of early stage breast cancer in the Auckland and Waikato regions of New Zealand Background
The aim of this study was to understand the factors influencing the use of surgical options by New Zealand women with newly diagnosed breast cancer.

Methods
Using data from the Auckland and Waikato breast cancer registers, we included 11 798 women diagnosed with stage I–III breast cancer from June 2000 to May 2013. The characteristics of women receiving different surgical treatments and having immediate breast reconstruction following mastectomy were examined. A logistic regression was used to estimate the odds ratio of having breast‐conserving surgery (BCS) versus mastectomy and immediate post‐mastectomy reconstruction. Bilateral breast cancer cases and women with unilateral breast cancer, but who had bilateral surgery, were also identified.

Results
Fifty‐two percent of women received BCS and 44% had mastectomy over the study period. Key influences associated with BCS were age, mode of diagnosis, socio‐economic status and public or private treatment. Just under half of the women who underwent bilateral surgery did not have bilateral cancer. Nineteen percent of women undergoing mastectomy underwent immediate reconstruction. Implant use increased slightly over the study period but there was a decrease in the use of autologous flap procedures.

Conclusion
Surgical management of women with localized breast cancer was generally in line with guidelines, but with potential to further increase the use of breast conservation and immediate reconstruction in suitable cases.

year: 2018

title: Spatial and temporal characteristics of the underwater soundscape around the Motiti Protection Area: Ōtaiti/Astrolabe Reef and Motiti Island

authors: Riegel, Maria Sophie

subjects: Underwater Soundscapes

abstract: Marine ecosystems around the world have been impacted by degradation and loss of biodiversity as a result of human impacts and climate change. The monitoring and management of ecologically significant areas is vital in understanding the effects of habitat degradation on marine ecosystems. Traditional monitoring methods are often expensive, time consuming, labour intensive and invasive. Soundscapes offer a unique opportunity for monitoring habitats in a way that is cost effective, minimally invasive and efficient. The aim of this study was to use passive acoustic monitoring to create a baseline data set using ambient sound data to investigate the spatial and temporal changes in ambient sound pressure levels, and to identify biotic, abiotic and anthropogenic sound sources which make up the marine soundscapes at the Motiti Island and Ōtaiti/Astrolabe Reef. Five diverse and ecologically significant sites in the Motiti Protection Area – at Ōtaiti/Astrolabe Reef and Motiti Island, in the Bay of Plenty, New Zealand were selected and monitored over the course of a year. This provided a wide variety of data to show the diel, lunar and seasonal patterns and trends in acoustic biological activity in order to represent the ecosystems accurately. The results showed that all sites showed strong diel patterns, with a sound pressure level increase of ~6-10dB during daylight hours compared to dark hours, and evident peaks during dawn and dusk hours as a result of biological choruses composed largely of sea urchins. There were also strong seasonal trends among the five sites, with Summer having the overall highest sound pressure level compared to Spring, Autumn and Winter, this also had an effect on the peaks in dusk choruses, which were also found to be highest during Summer. Lunar phases were also found to have an impact on the sound pressure levels of all five sites, with increased sound pressure levels during the new moon, compared to sound pressure levels during the full moon. This study created a baseline data set for a culturally, ecologically, and economically valuable area. Passive acoustic monitoring was found to be an incredibly useful tool in understand the ecosystems health and biological condition, and offers an alternative to traditional monitoring which is an effective, minimally invasive, and less labour intensive way of monitoring marine ecosystems.

text: Spatial and temporal characteristics of the underwater soundscape around the Motiti Protection Area: Ōtaiti/Astrolabe Reef and Motiti Island Marine ecosystems around the world have been impacted by degradation and loss of biodiversity as a result of human impacts and climate change. The monitoring and management of ecologically significant areas is vital in understanding the effects of habitat degradation on marine ecosystems. Traditional monitoring methods are often expensive, time consuming, labour intensive and invasive. Soundscapes offer a unique opportunity for monitoring habitats in a way that is cost effective, minimally invasive and efficient. The aim of this study was to use passive acoustic monitoring to create a baseline data set using ambient sound data to investigate the spatial and temporal changes in ambient sound pressure levels, and to identify biotic, abiotic and anthropogenic sound sources which make up the marine soundscapes at the Motiti Island and Ōtaiti/Astrolabe Reef. Five diverse and ecologically significant sites in the Motiti Protection Area – at Ōtaiti/Astrolabe Reef and Motiti Island, in the Bay of Plenty, New Zealand were selected and monitored over the course of a year. This provided a wide variety of data to show the diel, lunar and seasonal patterns and trends in acoustic biological activity in order to represent the ecosystems accurately. The results showed that all sites showed strong diel patterns, with a sound pressure level increase of ~6-10dB during daylight hours compared to dark hours, and evident peaks during dawn and dusk hours as a result of biological choruses composed largely of sea urchins. There were also strong seasonal trends among the five sites, with Summer having the overall highest sound pressure level compared to Spring, Autumn and Winter, this also had an effect on the peaks in dusk choruses, which were also found to be highest during Summer. Lunar phases were also found to have an impact on the sound pressure levels of all five sites, with increased sound pressure levels during the new moon, compared to sound pressure levels during the full moon. This study created a baseline data set for a culturally, ecologically, and economically valuable area. Passive acoustic monitoring was found to be an incredibly useful tool in understand the ecosystems health and biological condition, and offers an alternative to traditional monitoring which is an effective, minimally invasive, and less labour intensive way of monitoring marine ecosystems.

year: 2022