Undervisning och lärande är grundbultar i ett modernt demokratiskt samhälle. Dessa aktiviteter sker i stor utsträckning av lärare vilka bär ansvaret för att utbilda framtidens generationer. Inom utbildningsväsendet existerar en rad olika läromedel såsom böcker och datorer vilka ofta tenderar att vara statiska i sitt förhållande till eleven. Enligt internationella kunskapsmätningar har svenska elevers matematiska kunskap stagnerat de senaste två decennierna, även om en vändning har skett de senaste åren. En möjlig förklaring till detta kan vara att ett för stort fokus hos bl.a. lärare och matematikböcker ägnats åt procedurella färdigheter snarare än begreppslig förståelse. Detta i kombination med lärares upplevda svårigheter kring att tillämpa ett formativt arbetssätt kan innebära hinder för elevers matematiska kunskapsutveckling. Flera digitala verktyg har utvecklats för att stötta lärare och elever i deras lärandeprocess. Ett sådant digitalt verktyg är Mentimeter som utvecklats för att öka interaktionen mellan en presentatör (t.ex. en lärare) och dess publik. Mentimeterär inte avsett specifikt för en lärandekontext och det finns idag ingen etablerad utgivning av läromedel som använder Mentimeter för skolans värld. Det här examensarbetet har med bakgrund av detta haft som mål att designa och konstruera ett matematiskt läromedel med hjälp av Mentimeter, ämnat för att utveckla elevers förståelse för ett matematiskt begrepp (funktioner). Detta har gjorts med en designbaserad forskningsmetodik vilket är en metod som lämpar sig väl för att utveckla tekniska artefakter inom en skolkontext samt undersöka hur den utvecklade artefakten fungerar i en specifik kontext. Syftet med studien har varit att undersöka lärares upplevelse av att använda det utvecklade läromedlet och med den kunskapen, genom en iterativ process utveckla och samtidigt öka förståelse för hur ett digitalt utbildningsverktyg kan möjliggöra ett formativt arbetssätt. Ett grundantagande inom ramen för detta examensarbete är att ett formativt arbetssätt kan bidra till ett ökat lärande och därmed ökad förståelse för funktionsbegreppet, men att det behövs mer kunskap för att förstå sambandet mellan didaktisk teori och hur den kan användas inom en skolkontext. Detta examensarbete utgår både från en konstruktivistisk och en sociokulturell syn på lärande. Motiveringen av denna breda syn på lärande är att det möjliggör en mer induktiv ansats i förhållande till tolkningen av studiens resultat. Studiens resultat är en“Mentimeter-modul” som designats för att möjliggöra ökad förståelse för matematiska begrepp, samt en teoretisk förståelse för hur modulen upplevts av lärare i en skolkontext. Vidare visar studiens resultat på vikten av att lärare använder Mentimeter-modulen som ett komplement till den ordinarie undervisningen istället för att låta verktyget agera som en egen aktör. Slutsatsen är att den utvecklade Mentimeter-modulen upplevs möjliggöra ett formativt arbetssätt om syftet med modulen tydliggörs och lärarna ser på modulen som ett komplement till sin ordinarie undervisning. / Teaching and learning could be considered as cornerstones of a modern democratic society. These activities are largely being practiced by teachers who are in part responsible for educating future generations. In the education system, there are a number of different teaching materials such as books and computers, which often tend to be static with no or little interaction with the student. According to international surveys the mathematical knowledge among Swedish student’s has stagnated over the past two decades, although a turnaround has taken place in recent years. A possible explanation for this may be that too much focus has been devoted to procedural skills rather than conceptual understanding. This, combined with teachers' perceived difficulties in applying a formative approach, can slow down the development of students' mathematical knowledge. Several digital educational tools have been developed to support teachers and students in their learning process. One such tool is Mentimeter, which was developed to increase the interaction between a presenter (e.g. a teacher) and its audience (e.g. a student). Mentimeter is not intended specifically for a learning context and there is currently no mathematical educational materials developed with the software and that is accessible for everyone with a Menitemeter account. This master thesis has aimed to design and construct a mathematical teaching aid with the help of Mentimeter, intended to develop students' understanding of a mathematical concept (functions). This has been done with a design-based research methodology which is suited for exploring learning environments and gaining deeper theoretical understanding by introducing a designed technical artifact in the context that is being observed. The purpose of this Master Thesis has been to investigate teachers' experience of using the developed teaching aid and with that knowledge, through an iterative process develop understanding on how a digital educational tool can enable a formative approach. A basic assumption made by the authors of this study is that a formative approach can contribute to increased learning andthus increased understanding of the concept of a function. But more knowledge is needed to understand the connection between the didactic theory and how it can be applied in a school context. This study is based partly on a constructivist view of learning but also on a socio-cultural perspective. The motivation for this broad view of learning enables a more inductive approach in relation to the interpretation of the study results. The results of this thesis are a “Mentimeter module” designed to enable an increased understanding of mathematical concepts, as well as a theoretical understanding of how the module is experienced by teachers in a school context. Furthermore, the study shows the importance of teachers using the Mentimeter module as a complement to their regular teaching activities instead of letting the digital education tool act on its own. The conclusion is that the developed Mentimeter module is perceived to enable a formative approach if the purpose of the module is clarified and the teachers see the module as a complement to their established experience andprevious knowledge.

This study investigates the application and implications of AI-generated content in podcast production. The research particularly explores the use of text-to-speech (TTS) systems and AI language models to simulate authentic-sounding conversations. This study analyzes listener responses to different AI-generated and human-edited podcast episodes through a series of prototypes and interviews with listeners. Findings suggest that listeners often perceive AI-generated conversations as less authentic and natural than human-made ones, especially due to issues like unnatural intonation and a lack of natural discourse markers. Despite these challenges, improvements were noted in later prototypes where manual editing was combined with AI-generated content. This highlights the potential for AI to complement human creativity in podcast production. The study concludes that for AI-generated content to achieve the desired level of authenticity, further involvement of human intuition is necessary. Future research should explore refining AI models to better simulate natural conversation flow and focus on enhancing the nuances of human-like speech. The findings also underline the potential of AI tools to revolutionize podcast production workflows. / Denna studie undersöker användningen och implikationerna av AI-genererat innehåll i podcastproduktion. Forskningen utforskar särskilt användningen av text-till-tal-system (TTS) och AI-språkmodeller för att simulera samtal som låter autentiska. Studien analyserar lyssnarreaktioner på olika AI-genererade och mänskligt redigerade poddavsnitt genom en serie prototyper och intervjuer med lyssnare. Resultaten visar att lyssnare ofta upplever AI-genererade samtal som mindre autentiska och naturliga än de som skapats av människor. Särskilt på grund av problem som onaturliga betoningar och brist på naturliga diskurspartiklar. Trots dessa utmaningar märktes förbättringar i senare prototyper där manuell redigering kombinerades med AI-genererat innehåll, vilket belyser potentialen för AI att komplettera mänsklig kreativitet i podcastproduktion. Genom forskningen dras slutsatsen att AI-genererat innehåll kräver ytterligare integration av mänsklig intuition för att uppnå önskad nivå av autenticitet. Framtida forskning bör utforska hur AI-modeller kan förfinas för att bättre simulera naturligt samtalsflöde och fokusera på att förbättra nyanserna i mänskligt tal. Resultaten understryker också potentialen hos AI-verktyg att revolutionera arbetsflödena för podcastproduktion.

The purpose of this study was to design a local theory explaining the relationship between metacognitive language and networks as constructs of a local instructional theory in the context of a fourth-year intermediate phase mathematics education methodology module. The local instructional theory was designed to facilitate an adapted lesson study through a problem-based learning instructional philosophy. A problem-based learning task was then designed outlining the education needs and resources of a South African primary school, characteristic of schools in a rural area. In particular the task describes a fictitious teacher’s concern for teaching a Grade 6 mathematics class the concept of place value. Two groups of students, who volunteered to participate in this research, collaboratively designed and presented research lessons across two educational design-based research cycles for two rural schools in North West, as a form of service learning. In implementing the local instructional theory phases, participants were required to follow the lesson study approach by investigating, planning, developing, presenting, reflecting, refining and re-presenting the research lesson and its resources. These design sessions were videorecorded, transcribed and then coded in Atlas.ti through interpretivistic and hermeneutic analysis. The coded data were then imported into NodeXL to illustrate embedded networks. Not only social network data but also metacognitive network data were visualised in terms of metacognitive networks. The results show that across the local instructional theory phases, constructs of metacognition, metacognitive language and networking emerged on a social (stratum 1), interpersonal (stratum 2) and social-metacognitive (stratum 3) level. Collectively, these strata form the architecture of the theory of metacognitive locale that explains the relationship between the constructs. The findings suggest that when students express their metacognitive processes through a metacognitive language (e.g. I am thinking or feeling), their interpersonal metacognitive networks develop into shared metacognitive experiences which foster their metacognitive locale, a dimension of their metacognitive language and networking. / PhD (Mathematics Education), North-West University, Potchefstroom Campus, 2015

The purpose of this study was to design a local theory explaining the relationship between metacognitive language and networks as constructs of a local instructional theory in the context of a fourth-year intermediate phase mathematics education methodology module. The local instructional theory was designed to facilitate an adapted lesson study through a problem-based learning instructional philosophy. A problem-based learning task was then designed outlining the education needs and resources of a South African primary school, characteristic of schools in a rural area. In particular the task describes a fictitious teacher’s concern for teaching a Grade 6 mathematics class the concept of place value. Two groups of students, who volunteered to participate in this research, collaboratively designed and presented research lessons across two educational design-based research cycles for two rural schools in North West, as a form of service learning. In implementing the local instructional theory phases, participants were required to follow the lesson study approach by investigating, planning, developing, presenting, reflecting, refining and re-presenting the research lesson and its resources. These design sessions were videorecorded, transcribed and then coded in Atlas.ti through interpretivistic and hermeneutic analysis. The coded data were then imported into NodeXL to illustrate embedded networks. Not only social network data but also metacognitive network data were visualised in terms of metacognitive networks. The results show that across the local instructional theory phases, constructs of metacognition, metacognitive language and networking emerged on a social (stratum 1), interpersonal (stratum 2) and social-metacognitive (stratum 3) level. Collectively, these strata form the architecture of the theory of metacognitive locale that explains the relationship between the constructs. The findings suggest that when students express their metacognitive processes through a metacognitive language (e.g. I am thinking or feeling), their interpersonal metacognitive networks develop into shared metacognitive experiences which foster their metacognitive locale, a dimension of their metacognitive language and networking. / PhD (Mathematics Education), North-West University, Potchefstroom Campus, 2015

The aim of this study is to ascertain what misconceptions N2 students have about DC resistive circuits and how screencasts could effect on the rectification of these misconceptions. This study was conducted at the Kathu Campus of the Northern Cape Rural Further Education and Training College in the town Kathu in the arid Northern Cape. The empirical part of this study was conducted during the first six months of 2013. A design-based research (DBR) method consisting of four phases was used. DBR function is to design and develop interventions such as a procedure, new teachinglearning strategies, and in the case of this study a technology-enhanced learning (TEL) tool (screencast) with the purpose of solving a versatile didactic problem and to acquire information about the interventions of the TEL tool (screencast) on the learning of a student. In the first and second phase of DBR quantitative data for this research were gathered with the Determining and Interpreting Resistive Electric circuits Concepts Test (DIRECT) in order to determine the four most common misconceptions. The DIRECT test was conducted in the first trimester to find the misconceptions; the test was conducted in the second trimester also to confirm the misconceptions. Further quantitative data were collected from a demographic questionnaire. The qualitative data were collected by individual interviews in the fourth phase of the research project. Phase three of this study was the development of screencasts in the four most prominent misconceptions in DC resistive circuits of the students. The respondents of this study were non-randomly chosen and comprised of two groups, one in the first trimester of the year and one in the second trimester of the year, which enrolled for the N2 Electrical or Millwright courses. The respondents were predominant male and representing the three main cultural groups in the Northern Cape namely: Black, Coloured and White. The four misconceptions on DC resistive circuits that were identified were: (i) understanding of concepts, (ii) understanding of short circuit, (iii) battery as a constant current source, and (iv) rule application error. Screencasts clarifying the four misconceptions were developed and distributed to the respondents. On the foundation of the results of this research, it can be concluded that the students have several misconceptions around direct current resistive direct current circuits and that the use of TEL like screencasts can be used to solve some of these misconceptions. Screencasts could supplement education when they were incorporated into the tutoring and learning for supporting student understanding. The results of this research could lead to the further development and refinement of screencasts on DC resistive circuits and also useable guidelines in creating innovative screencasts on DC resistive circuits. / MEd (Curriculum Development), North-West University, Potchefstroom Campus, 2014

La géométrie à l'école primaire consiste en une familiarisation avec des formes géométriques et leurs propriétés, à travers l'utilisation d'instruments de géométrie. Les objets géométriques reposent sur les représentations graphiques, les relations géométriques sont souvent implicites. L'introduction d'un logiciel de géométrie dynamique (TracenPoche) est vu comme un moyen de les expliciter, conduisant ainsi à voir le dessin comme une figure. Nous avons proposé à des professeurs une série de cinq situations, que nous avons conçues à partir des modes d'intégration de Assude (2007). Nous en proposons une analyse a priori en trois temps (Assude et Mercier, 2007), une analyse a priori du point de vue des savoirs mathématiques, une analyse a priori ascendante du point de vue des actions des élèves modélisée en terme de praxéologie (Chevallard, 1998) et une analyse a priori du point de vue de l'enseignant. Les situations mises en oeuvre dans les classes sont décrites et analysées à l'aide d'éléments de la théorie de l'action conjointe en didactique (TACD, Sensevy, 2011). Nous décrivons l'action conjointe du professeur et des élèves comme un jeu du professeur sur l'élève, permettant ainsi de rendre compte de la dynamique du travail didactique et de l'évolution du « voir un dessin comme une figure ». Les résultats de la thèse, dans le cadre de cette ingénierie exploratoire (Perrin-Glorian, 2009), montrent comment les objets géométriques peuvent être travaillés conjointement dans l'environnement papier-crayon et dans l'environnement tracenpoche, mettant en évidence des caractéristiques de l'action conjointe du professeur et des élèves dans l'explicitation des relations géométriques. / Geometry in primary school is a familiarization with geometric shapes and their properties through the use of geometrical instruments. Geometric objects are based on diagrams and the geometric relationships are often implicit. The introduction of a dynamic geometry software (here TracenPoche) is thus a way to explain how to see « the diagram » as « a figure ». Five situations are given to three teachers. We have built them with « integration modes » from Assude (2007). We proposed an a priori analysis in three stages (Assude and Mercier, 2007), the first a priori analysis - the viewpoint of mathematical knowledge - , the second a priori analysis - students action modelized by the praxeology (Chevallard, 1998) - and the third a priori analysis - the teacher's point of view - . The Situations established in classrooms are described and analyzed using elements of the joint action theory (Sensevy, 2011). We describe the joint action of the teacher and students as a game of the teacher on the student, thereby enabling an analysis of the dynamic of the teaching work and of the evolution of the "seeing a diagram as a figure." The results of this thesis, as part of the exploratory engineering (Perrin-Glorian, 2009), show how geometrical objects can be worked jointly in a paper-and-pencil environment and in a Tracenpoche environment, highlighting the characteristics of the joint action of the teacher and students in the explanation of geometric relationships. The teachers demonstrate initiatives that prove particularly interesting with regard to mathematical issues, and which could be the basis for further research in cooperative engineering (Sensevy & al., 2013).

本研究旨在運用點讀筆輔助國中文言文補救教學，基於設計研究法迭代改進的過程，設計點讀筆輔助國中文言文補救教材及學習策略，並驗證其對於國文補救教學的效益。本研究以高雄市某國中二年級參與國文補救教學共6位八年級學生為研究對象，以設計研究法在教學實際現場基於學生學習過程中的質化觀測訪談紀錄，以及學習成效前後測與點讀筆內建學習歷程記錄等量化數據資料分析結果，進行包括準備（分析、設計）、執行（發展、實施）、評鑑（反省、產出）之循環迭代改進過程，以探究與發展結合點讀筆與紙本課文輔助文言文補救教學教材與學習策設計，為教師運用點讀筆發展文言文補救教學教材提供可行之實施模式。 結果顯示，本研究透過設計研究法發展出一套可有效輔以文言文補救學習之點讀筆搭配紙本教材與學習策略模式，並經由兩次循環修正歷程，產出一套較佳之點讀筆搭配紙本與學習策略模式之教材設計。本研究歸納在設計上應考量點讀的搭配性、自學的引導性、內容的適切性，並建立程序指引提醒，以發揮點讀筆搭配紙本輔助閱讀學習之功能。本研究產出之點讀教材，可透過碼點貼紙支援文言文學習所需之背景知識的補充、課文朗讀與背誦、文意理解、提出問題深入思考等學習需求，也搭配SQ3R學習策略流程引導，適合於學習者自學，並且可以進行重複學習，學生具有高度自主性，為學習落後學生搭建一有效之學習鷹架，培養學生帶得走的能力，為國文補救教學開創一有效且創新的學習模式。 / This study aims to apply digital pens to assisting in the literary Chinese remedial instruction in junior high schools. Based on the process of Design-based Research iterative improvement, the digital pen supported literary Chinese remedial teaching materials and learning strategies are designed, and the Chinese remedial learning efficiency is verified. Six G8 students in a junior high school in Kaohsiung City participating in the Chinese remedial instruction are studied. With Design-based Research, the qualitative observation and interview records of the students’ learning process and the quantitative data analyses of the pretest and posttest of learning performance and the digital pen built-in learning process records are preceded cyclic iterative improvement, including preparation (analysis and design), practice (development and implementation), and assessment (introspection and output) to explore and develop the design of digital pen supported and paper-based texts integrated literary Chinese remedial teaching materials and learning strategies. It is expected to provide a feasible model for teachers developing digital pen supported literary Chinese remedial teaching materials. The results show that an effective literary Chinese remedial instruction integrated with digital pen supported and paper-based materials and the learning strategies could be developed through Design-based Research. Furthermore, with two cyclic revision processes, the better digital pen supported and paper-based integrated material design and learning strategies could be generated. It is concluded in this study that the collocation of digital pen, the guiding for self-learning, and the content appropriateness should be taken into account of the design, and the procedural guideline reminder should be established to present the function of digital pen supported and paper-based reading learning. Through code stickers, the digital pen supported materials could supplement the required background knowledge for literary Chinese learning, text reading and recitation, content comprehension, and in-depth thinking with problems. With the guidance of SQ3R learning strategies, it is suitable for self-learning and could be proceeded repeated learning and the students present high autonomy so as to build a learning scaffold for the students fell behind in learning, to cultivate students with the abilities to take away, and to create an effective and innovative learning model for Chinese remedial instruction.

A key challenge of the learning sciences is moving research results into practice. Educators on the front lines perceive little value in the outputs of education research and demand more “usable knowledge”. This work explores the potential instead of usable artifacts to translate knowledge into practice, adding scientists as stakeholders in an interaction design process. The contributions are two effective systems, the scientific and contextual principles in their design, and a research model for scientific research through interaction design. College student study practices are the domain chosen for the development of these methods. Iterative ethnographic fieldwork identified two systems that would be likely to advance both learning in practice and knowledge for applying the employed theories in general. Nudge was designed to improve students’ study time management by regularly emailing students with explicit recommended study activities. It reconceptualizes the syllabus into an interactive guide that fits into modern students' attention streams. Examplify was designed to improve how students learn from worked example problems by modularizing them into steps and scaffolding their metacognitive behaviors though problem-solving and self-explanation prompts. It combines these techniques in a way that is exceedingly easy to author, using existing answer keys and students' self-evaluations. Nudge and Examplify were evaluated experimentally over a full semester of a lecture-based introductory chemistry course. Nudge messages increased students’ sense of achievement and interacted with students’ existing time management skills to improve exam grades for poorer students. Among students who could choose whether to receive them, 80% did. Students with access to Examplify had higher exam scores (d=0.26), especially on delayed measures of learning (d=0.40). A key design decision in Examplify was not clearly resolvable by existing theory and so was tested experimentally by comparing two variants, one without prompts to solve the steps. The variant without problem solving was less effective (d=0.77) and less used, while usage rates of the variant with problem solving increased over time. These results support the use of the design methods employed and provide specific empirical recommendations for future designs of these and similar systems for implementing theory in practice.

The aim of this study is to ascertain what misconceptions N2 students have about DC resistive circuits and how screencasts could effect on the rectification of these misconceptions. This study was conducted at the Kathu Campus of the Northern Cape Rural Further Education and Training College in the town Kathu in the arid Northern Cape. The empirical part of this study was conducted during the first six months of 2013. A design-based research (DBR) method consisting of four phases was used. DBR function is to design and develop interventions such as a procedure, new teachinglearning strategies, and in the case of this study a technology-enhanced learning (TEL) tool (screencast) with the purpose of solving a versatile didactic problem and to acquire information about the interventions of the TEL tool (screencast) on the learning of a student. In the first and second phase of DBR quantitative data for this research were gathered with the Determining and Interpreting Resistive Electric circuits Concepts Test (DIRECT) in order to determine the four most common misconceptions. The DIRECT test was conducted in the first trimester to find the misconceptions; the test was conducted in the second trimester also to confirm the misconceptions. Further quantitative data were collected from a demographic questionnaire. The qualitative data were collected by individual interviews in the fourth phase of the research project. Phase three of this study was the development of screencasts in the four most prominent misconceptions in DC resistive circuits of the students. The respondents of this study were non-randomly chosen and comprised of two groups, one in the first trimester of the year and one in the second trimester of the year, which enrolled for the N2 Electrical or Millwright courses. The respondents were predominant male and representing the three main cultural groups in the Northern Cape namely: Black, Coloured and White. The four misconceptions on DC resistive circuits that were identified were: (i) understanding of concepts, (ii) understanding of short circuit, (iii) battery as a constant current source, and (iv) rule application error. Screencasts clarifying the four misconceptions were developed and distributed to the respondents. On the foundation of the results of this research, it can be concluded that the students have several misconceptions around direct current resistive direct current circuits and that the use of TEL like screencasts can be used to solve some of these misconceptions. Screencasts could supplement education when they were incorporated into the tutoring and learning for supporting student understanding. The results of this research could lead to the further development and refinement of screencasts on DC resistive circuits and also useable guidelines in creating innovative screencasts on DC resistive circuits. / MEd (Curriculum Development), North-West University, Potchefstroom Campus, 2014

Thesis (PhD)--Macquarie University, Division of Information and Communication Sciences, Computing Department, 2008. / Bibliography: p. 503-514. / This study investigated learning design in a web-conferencing environment based on three semesters of lessons conducted as part of an introductory programming subject. As well as characterizing the nature of discourse and interaction, the study focused on how the design of the interface, activity and task type affected collaboration and learning. Engeström's (1987) Activity Theory based upon a socio-constructivist view of learning was used to frame the analysis. --Interface designs incorporated theory relating to graphical user interface design, multimedia learning, and findings from the cognitive sciences. Activity designs were differentiated based on the degree of student ownership, from teacher-centred (transmissive) approaches, to teacher-led (guided interaction) approaches, to student-centred (collaborative group-work) designs. Types of tasks were considered on the basis of their level of knowledge (declarative, procedural and conceptual), their character (authenticity, situatedness) and their domain specific nature (in the field of computer science education). The effects of the different interface, activity and task designs on collaboration and mental model formation were explored. --A mixed method approach to analysis was adopted, incorporating a design-based research study and a multimodal discourse analysis. The design-based research allowed a broader, more interpretivistic and process focused analysis to be conducted, based on the strategic redesigns that occurred between iterations of the subject. The multimodal discourse analysis enabled more detailed, objective and outcomes based measurements of the subject of discourse, the nature of interactions and the types of modalities used to mediate learning. Triangulating data from the design-based research study and the multimodal discourse analysis provided a more complete description of phenomena and promoted greater reliability. --Results include the way in which different modalities afforded different possibilities for representing, and how combinations of those modalities could be effectively integrated by applying multimedia learning principles. Student-centred learning designs increased student involvement, allowing them to take greater ownership over the content and to more fully share their mental models. Authentic, meaningful problem solving tasks promoted greater student engagement. The capacity to dynamically redesign the interface based on the collaborative and cognitive requirements of the learning episode supported more effective implementation of conversational (Laurillard, 2002) approaches to learning. --More effective interaction and collaboration resulted from prescribing patterns of engagement, managing activity and technology so that student discourse could focus on content, and providing guidance regarding semiotic representational forms so that students could concentrate on applying those representations rather than inventing them. Teacher and student virtual classroom competencies critically influenced collaboration and learning. --Based on the findings in this study, a framework of nine pedagogical patterns for teaching and learning in web-conferencing environments is proposed. The framework provides an integrated approach to learning design that relates the interface design with the activity design and the level of knowledge (task type). / Mode of access: World Wide Web. / vii, 514 p. ill. (some col.)