235 research outputs found
Effects of pendent phenol functional groups on secondary coordination spheres of heme like Fe-salen complexes
No full textSince the beginning of industrial revolution, burning of fossil fuels has mainly led to increase in atmospheric concentration of CO2 , a Green House Gas (GHG), from 250 ppm to 400 ppm between 1800 and 2012. One way to reduce the burning of fossil fuels and CO2 emission rate is to explore alternative carbon free fuels to meet the energy demand.This project aims at the synthesis and study of metal complexes inspired by biological models that will help better design catalysts to perform water oxidation more effectively.This poster won the Dean, Faculty of Science award (2020). Advisor: Dr. Linus Chiang, Departmen of Chemistry
21st-century scholarship and Wikipedia
No full textWikipedia, the world’s fifth most-used Web site, is a good illustration of the growing credibility of online resources. In his article in Ariadne earlier this year, “Wikipedia: Reflections on Use and Academic Acceptance”, Brian Whalley described the debates around accuracy and review, in the context of geology. He concluded that ‘If Wikipedia is the first port of call, as it already seems to be, for information requirement traffic, then there is a commitment to build on Open Educational Resources (OERs) of various kinds and improve their quality.’ In a similar approach to the Geological Society event that Whalley describes, Sarah Fahmy of JISC worked with Wikimedia and the British Library on a World War One (WWI) Editathon. There is a rich discourse about the way that academics relate to Wikipedia
Query-Efficient Correlation Clustering via Active Learning of Pairwise Similarities [Elektronisk resurs]
No full textClustering is an important unsupervised learning problem used to group objects based on their characteristics. Correlation clustering is arguably the most natural form of clustering because it only assumes access to a pairwise similarity measure between objects, where the similarities can be expressed as any positive or negative real number. This makes correlation clustering widely applicable to many problems, even when high quality feature vectors are not available. However, obtaining pairwise similarities between all objects may be expensive and impractical in many contexts. Motivated by this, we study the problem of finding high quality correlation clustering solutions with a constrained budget of queries for pairwise similarities. Acquiring the most informative data within a constrained budget is generally studied in the field of active learning . Therefore, we develop a generic pool-based batch active learning procedure with the purpose of performing query-efficient correlation clustering, which is highly robust to noisy oracle feedback
Integrerat brounderhåll
No full textTrafikverket ansvarar för det statliga vägnätet i Sverige. Vägnätet består av cirka 15 500 broar som ständigt utsätts för olika former av nedbrytning. Broarna behöver därför underhållas med jämna mellanrum både för att hålla broarna i ett bra skick och för att motverka att nedbrytningen påskyndas. Under de senare åren har Trafikverket utformat en ny upphandlingsmetod av brounderhåll. Den går ut på att allt brounderhåll för en region paketeras, i ett s.k. brounderhållspaket, som en entreprenör sköter i en femårig period. I brounderhållspaketen ingår förebyggande underhåll, avhjälpande underhåll och akut underhåll. Syftet med det här arbetet är att följa upp den nya formen att upphandla brounderhåll i paket. Målet är att tydliggöra vilka vinster, eller förluster, som gjorts i effektivitet i hela kedjan sedan införandet av brounderhåll i paket. De metoder som använts vid skapandet av examensarbetet är litteraturstudier, möten och intervjuer samt analyser, beräkningar och jämförelser. Resultatet visar hur beställare, entreprenör och konsult arbetar i brounderhållspaket och vad som har förändrats jämfört med hur de arbetade med brounderhåll tidigare. De största effektivitetsvinsterna är administrativa. Genom att brounderhållspaketen är en totalentreprenad läggs mycket av ansvaret över från beställaren till entreprenören och därmed får beställaren tid till andra arbetsuppgifter. Eftersom brounderhållet numera ligger i eget kontrakt som löper under en längre tid får beställaren också en kunnig entreprenör till arbetet vilket minskar antalet grundläggande frågor och frigör tid. Entreprenören får mer frihet när arbetena skall utföras och samtidigt mer tid till att planera underhållsarbetet. Genom en tät kommunikation mellan beställare och entreprenör blir beslutsvägarna kortare vilket effektiviserar hela kedjan. Skaraborgspaketet var ett av de första brounderhållspaketen och det skiljer sig mycket från de senare underhållspaketen. Den största förändringen ligger i förfrågningsunderlagen. Skaraborgspaketet utgick från en fiktiv bro medan förfrågningsunderlagen i de nyare paketen behandlar verkliga åtgärder som entreprenören kommer att utföra under den kontrakterade tiden.Trafikverket is responsible for the public traffic network in Sweden. The traffic network contains around 15 500 bridges that constantly are exposed of different kinds of degradation. The bridges must therefore be maintained at regular intervals both to keep bridges in good condition and to prevent the degradation accelerated. During the last years Trafikverket has developed a new procurement method of bridge maintenance. The method involves that all bridges maintenance of a region is being bundled to one contract that an entrepreneur handles for five years, a socalled bridge maintenance package. A bridge maintenance package exists of preventive maintenance, remedial maintenance and emergency maintenance. The purpose of this paper is to follow up the new form to procure bridge maintenance in package. The goal is to clarify the gains or losses made in efficiency since the introduction of bridge maintenance in package. Methods used in the creating of this thesis are literary studies, meetings and interviews along with analysis, calculations and comparisons. The result lays the foundation for the client, contractor and consultant working in the bridge maintenance package and further what has changed from the way they were working on bridge maintenance earlier. The largest efficiency gains are administrative. Because a bridge maintenance package is a turnkey contract the majority of responsibility is put on the contractor, instead of the client, which gives the client time for other tasks. Nowadays the bridge maintenance is in a separate contract which lasts for a longer time which gives the client a more qualified contractor for that kind of work which is reducing the number of fundamental questions and gives the client extra time. The contractor will get more operating freedom and at the same time more time to plan maintenance work. Through frequent communication between client and contractor decision-making paths becomes shorter which gives more efficiency throughout the entire process. The package in the region Skaraborg was one of the first bridge maintenance packages and it differs a lot from later maintenance packages. The biggest difference is in the contract documents. The package in Skaraborg was based on a fictional bridge while the more recent maintenance packages documents addresses the real action which the contractor will perform during the contracted period
Intraductal papillary mucinous neoplasms of the pancreas. Clinical management, health economy and biomarkers.
No full textHow Many Answers Are Enough? Optimal Number of Answers for Q&A Sites
No full textWith the proliferation of the social web, questions about information quality and optimization attract the attention of IS scholars. Question-answering (QA) sites, such as Yahoo!Answers, have the potential to produce good answers, but at the same time not all answers are good and not all QA sites are alike. When organizations design and plan for the integration of question answering services on their sites, identification of good answers and process optimization become critical. Arguing that ‘given enough answers all questions are answered successfully,’ this paper identifies the optimal number of posts that generate high quality answers. Based on content analysis of Yahoo! Answers’ informational questions (n=174) and their answers (n=1,023), the study found that seven answers per question are ‘enough’ to provide a good answer
Intraductal papillary mucinous neoplasms of the pancreas. Clinical management, health economy and biomarkers. [Elektronisk resurs]
No full textSecurity Log Analysis with Explainable Machine Learning
No full textPhysical access control systems are implemented to restrict access in order to prevent
attacks from happening in the physical space. These systems usually produce access
logs that contain information to track accesses made by users. The access logs can
however end up becoming large and difficult to interpret, making security assessment
impractical for administrators and as a consequence, the logs are rarely inspected.
The current method of detecting anomalies by manual inspection is often not a
feasible approach in preventing attacks. For this reason, anomaly detection using
machine learning is a method that can aid administrators in detecting attacks and
being able to proactively prevent them from happening again. In this thesis, we first
analyze users from a dataset of physical access logs and cluster them into groups
with similar behavior based on their access pattern. Next, we train two LSTM
autoencoder models for each cluster in order to detect anomalies of two different
access sequence lengths. Finally, we evaluate the model with the help of a security
expert from the industry by reviewing explanations produced using SHAP values.
The results in this thesis show that our method was able to reduce the number of
log events that need to be manually inspected by 95.6% in the given dataset. The
results also show that the explanations provided by SHAP values was able to help
in understanding what caused an anomaly. In conclusion, our proposed method is
advantageous compared to manual inspection as it greatly reduces the amount of
work required to detect anomalies, and the SHAP values are able to help security
administrators to work in a more proactive manner
Power Relations and Social Classes in Pengakuan Pariyem by Linus Suryadi AG: Reflection of Masculine Ideology
No full textThe study aims to explore power relations and social classes as the reflections of the masculine ideology of the author in the novel Pengakuan Pariyem by Linus Suryadi AG. The theories implemented in the study are van Dijk’s power relations and social classes theory and Connell’s masculinity theory. The study is qualitative descriptive and applies the Critical Discourse Analysis (CDA) method, used to dismantle the ideology that is produced and reproduced through the language within the novel. The research data are lingual units that indicate power relations and social classes which simultaneously reflect the notion of masculinity. The results of the study are as follows. First, Pariyem as the central character in the novel lives within a hierarchical and dualistic Javanese society. Her submission as the babu (housemaid) of a priyayi (noble) family does not only lead Pariyem to be dominated symbolically, but also legitimizes the priyayi (aristocrats) power over wong cilik (commoners). It is reinforced by the representations of the priyayis’ world views in terms of culture, aristocracy, bureaucracy, and education orientation. It shows that priyayis are culturally dominant. Secondly, since Pariyem is a character created by a male author, her behaviors and actions reflect the ideology of masculinity. Rather than voicing women, the power relations that Pariyem experiences through the events constructed in the novel show that she embodies the masculine ideology, or masculinity.
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