Improving storage performance through layout optimizations

Disk drives are the bottleneck in the processing of large amounts of data used in almost all common applications. File systems attempt to reduce this by storing data sequentially on the disk drives, thereby reducing the access latencies. Although this strategy is useful when data is retrieved sequentially, the access patterns in real world workloads is not necessarily sequential and this mismatch results in storage I/O performance degradation. This thesis demonstrates that one way to improve the storage performance is to reorganize data on disk drives in the same way in which it is mostly accessed. We identify two classes of accesses: static, where access patterns do not change over the lifetime of the data and dynamic, where access patterns frequently change over short durations of time, and propose, implement and evaluate layout strategies for each of these. Our strategies are implemented in a way that they can be seamlessly integrated or removed from the system as desired. We evaluate our layout strategies for static policies using tree-structured XML data where accesses to the storage device are mostly of two kinds���parent-to-child or child-to-sibling. Our results show that for a specific class of deep-focused queries, the existing file system layout policy performs better by 5���54X. For the non-deep-focused queries, our native layout mechanism shows an improvement of 3���127X. To improve performance of the dynamic access patterns, we implement a self-optimizing storage system that performs rearranges popular block accesses on a dedicated partition based on the observed workload characteristics. Our evaluation shows an improvement of over 80% in the disk busy times over a range of workloads. These results show that applying the knowledge of data access patterns for allocation decisions can substantially improve the I/O performance.

Factors influencing the implementation of substance use prevention programs in elementary schools

Prevention scientists have called for more research on the factors affecting the implementation of substance use prevention programs. Given the lack of literature in this area, coupled with evidence that children as early as elementary school engage in substance use, the purpose of this study was to identify the factors that influence the implementation of substance use prevention programs in elementary schools. This study involved a mixed methods approach comprised of a survey and in-person interviews. Sixty-five guidance counselors and teachers completed the survey, and 9 guidance counselors who completed the survey were interviewed individually. Correlation analyses and hierarchical multiple regression were conducted. Quantitative findings revealed ease of implementation most frequently influenced program implementation, followed by beliefs about the program's effectiveness. Qualitative findings showed curriculum modification as an important theme, as well as difficulty of program implementation. The in-person interviews also shed light on three interrelated themes influencing program implementation ��� The Wheel, time, and scheduling. Results indicate the majority of program providers modified the curriculum in some way. Implications for research, policy, and practice are discussed, and areas for future research are suggested.^

A Study of Teachers' Espoused Instructional Beliefs

The purpose of this study was to investigate teachers��� espoused instructional beliefs and whether they differed in relation to schools��� socioeconomic status, extent of teachers��� educational background, or extent of teachers��� classroom experience. The study comprised a total of 242 Miami-Dade County public school educators who responded to a thirty-nine question Likert scale, Literacy Instructional Practices Questionnaire. Eighteen schools, three from each of the six regions, were purposively selected based on the socioeconomic status of students. Nine participants were interviewed using semi-standardized interview procedures and open-ended questioning techniques. Multivariate Analysis of Variance (MANOVA) results revealed that teachers��� espoused beliefs concerning the instruction of literacy and forces and influences affecting instruction do not significantly differ depending on schools��� socioeconomic status, extent of teachers��� educational background, or extent of teachers��� classroom experience. The majority of teachers appear to follow a top-down generated direct instruction model. Generally, students are taught as a whole class and ability grouped for specific skill instruction utilizing commercially produced reading and language arts texts. There was no evidence of a relationship between teachers��� espoused beliefs concerning the model of instruction that they practice or teachers��� espoused beliefs concerning research and its application to practice and the three independent variables. Interview data corroborated much of the information garnered through the questionnaire. However, interview participants espoused the belief that research did not influence their selection of instructional practices. Although teachers perceive of themselves as eclectic in their espoused instructional beliefs, they appear to follow a skills based direct instruction pedagogy in practice. Much of what teachers believe constitutes effective practice, few researchers recommend, affirming the findings of Calderhead (1993) and the National Educational Research Policy and Priorities Board (U.S. Department of Education, 1998, p. 18) that ���educators rarely know research, seek it out, or act in accordance with its results.���

Improving Storage Performance Through Layout Optimizations

Disk drives are the bottleneck in the processing of large amounts of data used in almost all common applications. File systems attempt to reduce this by storing data sequentially on the disk drives, thereby reducing the access latencies. Although this strategy is useful when data is retrieved sequentially, the access patterns in real world workloads is not necessarily sequential and this mismatch results in storage I/O performance degradation. This thesis demonstrates that one way to improve the storage performance is to reorganize data on disk drives in the same way in which it is mostly accessed. We identify two classes of accesses: static, where access patterns do not change over the lifetime of the data and dynamic, where access patterns frequently change over short durations of time, and propose, implement and evaluate layout strategies for each of these. Our strategies are implemented in a way that they can be seamlessly integrated or removed from the system as desired. We evaluate our layout strategies for static policies using tree-structured XML data where accesses to the storage device are mostly of two kinds - parent-tochild or child-to-sibling. Our results show that for a specific class of deep-focused queries, the existing file system layout policy performs better by 5-54X. For the non-deep-focused queries, our native layout mechanism shows an improvement of 3-127X. To improve performance of the dynamic access patterns, we implement a self-optimizing storage system that performs rearranges popular block accesses on a dedicated partition based on the observed workload characteristics. Our evaluation shows an improvement of over 80% in the disk busy times over a range of workloads. These results show that applying the knowledge of data access patterns for allocation decisions can substantially improve the I/O performance.

Influence of climate change and human activities on the organic and inorganic composition of peat during the Little Ice Age (El Payo mire, W Spain)

Acknowledgements This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N. Silva-S��nchez is currently supported by a FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government. We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provide us data included in Figure 5a. We also want to thank constructive comments from two anonymous reviewers.

Influence of climate change and human activities on the organic and inorganic composition of peat during the ���Little Ice Age��� (El Payo mire, W Spain)

Acknowledgements This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N. Silva-S��nchez is currently supported by a FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government. We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provide us data included in Figure 5a. We also want to thank constructive comments from two anonymous reviewers.

The effectiveness of corporate Web in small and m��diumsized business: an analysis of Web Usability

Internet and the Web have changed the way that companies communicate with their publics, improving relations between them. Also providing substantial benefits for organizations. This has led to small and medium enterprises (SMEs) to develop corporate sites to establish relationships with their audiences. This paper, applying the methodology of content analysis, analyzes the main factors and tools that make the Websites usable and intuitive sites that promote better relations between SMEs and their audiences. Also, it has developed an index to measure the effectiveness of Webs from the perspective of usability. The results indicate that the Websites have, in general, appropriate levels of usability.

Adaptaci��n del sector tur��stico al cambio clim��tico en Espa��a. La importancia de las acciones a escala local y en empresas tur��sticas

El 5�� Informe del IPCC (Panel Intergubernamental de Cambio Clim��tico, 2014) se��ala que el turismo ser�� una de las actividades econ��micas que mayores efectos negativos experimentar�� en las pr��ximas d��cadas debido al calentamiento t��rmico del planeta. En Espa��a, el turismo es una fuente principal de ingresos y de creaci��n de puestos de trabajo en su econom��a. De ah�� que sea necesaria la puesta en marcha de medidas de adaptaci��n a la nueva realidad clim��tica que, en nuestro pa��s, va a suponer cambios en el confort clim��tico de los destinos e incremento de extremos atmosf��ricos. Frente a los planes de adaptaci��n al cambio clim��tico en la actividad tur��stica, elaborados por los gobiernos estatal y regional, que apenas se han desarrollado en Espa��a, la escala local muestra interesantes ejemplos de acciones de adaptaci��n al cambio clim��tico, desarrolladas tanto por los municipios (energ��a, transporte, vivienda, planificaci��n urban��stica) como por la propia empresa tur��stica (hoteles, campings, apartamentos). Medidas de ahorro de agua y luz, fomento del transporte p��blico y de las energ��as limpias, creaci��n de zonas verdes urbanas y adaptaci��n a los extremos atmosf��ricos destacan como acciones de mitigaci��n del cambio clim��tico en los destinos tur��sticos principales de nuestro pa��s.

Of Marx and Makers: an Historical Perspective on Generative Justice

In Marxist frameworks ���distributive justice��� depends on extracting value through a centralized state. Many new social movements���peer to peer economy, maker activism, community agriculture, queer ecology, etc.���take the opposite approach, keeping value in its unalienated form and allowing it to freely circulate from the bottom up. Unlike Marxism, there is no general theory for bottom-up, unalienated value circulation. This paper examines the concept of ���generative justice��� through an historical contrast between Marx���s writings and the indigenous cultures that he drew upon. Marx erroneously concluded that while indigenous cultures had unalienated forms of production, only centralized value extraction could allow the productivity needed for a high quality of life. To the contrary, indigenous cultures now provide a robust model for the ���gift economy��� that underpins open source technological production, agroecology, and restorative approaches to civil rights. Expanding Marx���s concept of unalienated labor value to include unalienated ecological (nonhuman) value, as well as the domain of freedom in speech, sexual orientation, spirituality and other forms of ���expressive��� value, we arrive at an historically informed perspective for generative justice.��

Hoe be��nvloeden de marktkenmerken de belemmeringen voor innovatie in de utiliteitsbouw in Nederland?

How do the market characteristics influence the obstacles to innovation in the non-residential building industry in the Netherlands? Innovation can make an important contribution to the firm���s competitive advantage. Within the nonresidential building industry in the Netherlands the competition is very high. Therefore there should be enough motivation to innovate. The building industry has been severely hit by the economic crisis in the past years in the Netherlands, which made the competition even harder. Nevertheless the industry has a poor reputation on innovation and is known as a conservative industry. In the past decade the industry and government have put a lot of effort into making the sector more innovative. Sadly the innovation level has hardly improved. Why does the building industry fail to make itself more innovative? To make a contribution to this issue a research can be conducted to investigate the causes of this low innovation level. Research This thesis tends to make more clear about the causes of the low innovation level. Based on an extensive field research as well as a literature research the main question of this thesis is: How do the market characteristics influence the obstacles to innovation in the non-residential building industry in the Netherlands? The structure is based on qualitative research through case study research. Therefore a conceptual model is structured which is used as a fundamental base. Within the first case 21 interviews were held with the prime actors which played a direct role in the innovation level of non-residential projects. These prime actors are clients, consultancy agencies and building contractors. Also two panel discussions were organized to discuss the outcomes of the interviews. In the second and third case a part of certain market characteristics of the conceptual model were changed. The main reason to investigate these cases is to substantiate the results of the first case.

���Optimaliserend Onderwijs��� voor elke leerling. Multiniveau theoretisch ontwerp en praktijkontwikkeling

Een review van onderwijsanalyses en (beleids)onderzoeken verricht in de periode 1916-2015 wijst uit dat de reguliere jaarklassensystematiek in het Nederlandse primair en voortgezet onderwijs aanleiding geeft tot prestatie- en motivatieproblemen bij risico-leerlingen. Dit zijn met name de leerlingen die qua ontwikkelingspotenties of leervorderingen (aanvankelijk) duidelijk naar beneden of naar boven afwijken van leeftijdsgenoten in een groep of klas. Ondervanging van deze problemen lijkt mogelijk via een preventieve systematiek van ���Optimaliserend Onderwijs��� voor elk kind in de v����r- of vroegschoolse educatie en elke leerling in het primair of voortgezet onderwijs. Een eerste vraag betreft de inhoudelijke en vormgevingskenmerken van dit onderwijsontwerp: welke richtlijnen en specificaties daarvan kunnen het onderwijs, spelen en leren voor elke leerling, zo optimaal mogelijk inhoud en vorm geven en hoe ziet een model van dit Optimaliserend Onderwijs eruit? Een tweede vraag is gericht op de realisatie van dit onderwijsontwerp: hoe is deze onderwijssystematiek te ontwikkelen in de Nederlandse schoolpraktijk? Gebruik van de sneeuwbalmethode in met name Nederlandse onderzoeks- en designliteratuur leidt tot beantwoording van de eerste vraag in de vorm van een multiniveau theoretisch ontwerp van ���Optimaliserend Onderwijs���. Kernpunten hierin zijn: landelijke (deel)curricula gekenmerkt door instructievarianten; integratie van dubbele diagnostiek (individueel-longitudinaal en vergelijkend-genormeerd); flexibele certificerings- en diplomeringsstructuur; een ondersteunende schoolorganisatie; gecontroleerde opbrengst-optimalisering per kind of leerling en op instellings- en schoolniveau; per v����r- of vroegschoolse instelling of school(bestuur) kunnen ook vrije ofwel eigen onderwijsinvullingen worden ingericht. Beantwoording van de tweede vraag gebeurt met behulp van (onderzoeks)literatuur over multiniveau onderwijsinnovatie in de schoolpraktijk. Aanbevolen wordt om, op basis van een gezamenlijk besluit van het ministerie van Onderwijs, Cultuur en Wetenschap, de Tweede Kamer, relevante onderwijsinstanties, schoolbesturen en ouderorganisaties, te komen tot inrichting van samenhangende ontwikkelingsprojecten en -onderzoeken. Via een projectenserie in instellingen voor v����r- of vroegschoolse educatie en scholen voor primair en voortgezet onderwijs kan gecontroleerd worden samengewerkt tussen leid(st)ers, leerkrachten en docenten, scholen, ontwikkelings- en andere onderwijsinstellingen, instellingen voor onderzoek en informatietechnologie, en onderwijspolitiek. Tussenresultaten van Optimaliserend Onderwijs worden steeds in andere instellingen en scholen beproefd en verder verspreid.

The Reliability and Validity of a Child and Adolescent Participation in Decision Making Questionnaire

Background<br/>There is a growing impetus across the research, policy and practice communities for children and young people to participate in decisions that affect their lives. Furthermore, there is a dearth of general instruments that measure children and young people���s views on their participation in decision making. This paper presents the reliability and validity of the Child and Adolescent Participation in Decision Making Questionnaire (CAP-DMQ) and specifically looks at a population of looked-after children where a lack of participation in decision making is an acute issue.<br/>Methods<br/>The participants were 151 looked after children and adolescents between 10-23 years of age who completed the 10 item CAP-DMQ. Of the participants 113 were in receipt of an advocacy service that had an aim of increasing participation in decision-making with the remaining participants not having received this service.<br/>Results<br/>The results showed that the CAP-DMQ had good reliability (Cronbach���s alpha = .94) and showed promising uni-dimensional construct validity through an exploratory factor analysis. The items in the CAP-DMQ also demonstrated good content validity by overlapping with prominent models of child and adolescent participation (Lundy 2007) and decision making (Halpern 2014). A regression analysis showed that age and gender were not significant predictors of CAP-DMQ scores but receipt of advocacy was a significant predictor of scores (effect size d=.88), thus showing appropriate discriminant criterion validity. <br/>Conclusion <br/>Overall, the CAP-DMQ showed good reliability and validity. Therefore, the measure has excellent promise for theoretical investigation in the area of child and adolescent participation in decision making and equally shows empirical promise for use as a measure in evaluating services which have increasing the participation of children and adolescents in decision making as an intended outcome. <br/>

Multilevel processes and cultural adaptation: examples from past and present small-scale societies

The last two decades have seen a proliferation of research frameworks that emphasise the importance of understanding adaptive processes that happen at different levels. We contribute to this growing body of literature by exploring how cultural (mal)adaptive dynamics relate to multilevel social-ecological processes occurring at different scales, where the lower levels combine into new units with new organizations, functions, and emergent properties or collective behaviors. After a brief review of the concept of &#8220;cultural adaptation&#8221; from the perspective of cultural evolutionary theory, the core of the paper is constructed around the exploration of multilevel processes occurring at the temporal, spatial, social, and political scales. We do so by using insights from cultural evolutionary theory and by examining small-scale societies as case studies. In each section, we discuss the importance of the selected scale for understanding cultural adaptation and then present an example that illustrates how multilevel processes in the selected scale help explain observed patterns in the cultural adaptive process. The last section of the paper discusses the potential of modeling and computer simulation for studying multilevel processes in cultural adaptation. We conclude by highlighting how elements from cultural evolutionary theory might enrich the multilevel process discussion in resilience theory.

Berufsausbildung und sozio-��konomischer Wandel. Ursachen der "Krise des dualen Systems" der Berufsausbildung

Zu einem Zeitpunkt, zu dem zahlreiche Entwicklungs- und neuerdings auch Industriel��nder das ���duale System" der Berufsausbildung in Deutschland als eine Art Idealmodell der beruflichen Qualifizierung entdecken, wachsen die Zweifel, ob dieses Ausbildungssystem angesichts der anhaltenden Expansion von Gymnasium und Hochschule noch eine Zukunftsperspektive hat. Im vorliegenden Beitrag werden die zahlreichen Symptome der Krise des dualen Systems aufgezeigt, es wird versucht, die Ursachen dieser Krise unter sozialhistorischer Fragestellung zu deuten, und es werden die bislang aufgezeigten Vorschl��ge diskutiert, diese Krise zu ��berwinden. (DIPF/Orig.)

'Introducing Dendritic Cells as a Novel Immune-Inspired Algorithm for Anomaly Detection'

Abstract. Dendritic cells are antigen presenting cells that provide a vital link between the innate and adaptive immune system. Research into this family of cells has revealed that they perform the role of coordinating T-cell based immune responses, both reactive and for generating tolerance. We have derived an algorithm based on the functionality of these cells, and have used the signals and differentiation pathways to build a control mechanism for an artificial immune system. We present our algorithmic details in addition to some preliminary results, where the algorithm was applied for the purpose of anomaly detection. We hope that this algorithm will eventually become the key component within a large, distributed immune system, based on sound immunological concepts.