Midline shift (MLS), the amount of displacement of the brain’s midline from its normal symmetric position due to illness or injury, is an important index for clinicians to assess the severity of traumatic brain injury (TBI). In this dissertation, an automated computer-aided midline shift estimation system is proposed. First, a CT slice selection algorithm (SSA) is designed to automatically select a subset of appropriate CT slices from a large number of raw images for MLS detection. Next, ideal midline detection is implemented based on skull bone anatomical features and global rotation assumptions. For the actual midline detection algorithm, a window selection algorithm (WSA) is applied first to confine the region of interest, then the variational level set method is used to segment the image and extract the ventricle contours. With a ventricle identification algorithm (VIA), the position of actual midline is detected based on the identified right and left lateral ventricle contours. Finally, the brain midline shift is calculated using the positions of detected ideal midline and actual midline. One of the important applications of midline shift in clinical medical decision making is to estimate the intracranial pressure (ICP). ICP monitoring is a standard procedure in the care of severe traumatic brain injury (TBI) patients. An automated ICP level prediction model based on machine learning method is proposed in this work. Multiple features, including midline shift, intracranial air cavities, ventricle size, texture patterns, and blood amount, are used in the ICP level prediction. Finally, the results are evaluated to assess the effectiveness of the proposed method in ICP level prediction.

Wireless digital broadcasting applications such as digital audio broadcast (DAB) and digital video broadcast (DVB) are becoming increasingly popular since the digital format allows for quality improvements as compared to traditional analogue broadcast. The broadcasting is commonly based on packet transmission. In this thesis, we consider broadcasting over packet erasure channels. To achieve reliable transmission, error-control schemes are needed. By carefully designing the error-control schemes, transmission efficiency can be improved compared to traditiona lautomatic repeat-request (ARQ) schemes and rateless codes. Here, we first study the application of a novel binary deterministic rateless (BDR) code. Then, we focus on the design of network coding for the wireless broadcasting system, which can significantly improve the system performance compared to traditional ARQ. Both the one-hop broadcasting system and a relay-aided broadcasting system areconsidered. In the one-hop broadcasting system, we investigate the application of systematic BDR (SBDR) codes and instantaneously decodable network coding (IDNC). For the SBDR codes, we determine the number of encoded redundancy packets that guarantees high broadcast transmission efficiencies and simultaneous lowcomplexity. Moreover, with limited feedback the efficiency performance can be further improved. Then, we propose an improved network coding scheme that can asymptotically achieve the theoretical lower bound on transmission overhead for a sufficiently large number of information packets. In the relay-aided system, we consider a scenario where the relay node operates in half duplex mode, and transmissions from the BS and the relay, respectively, are over orthogonal channels. Based on random network coding, a scheduling problem for the transmissions of redundancy packets from the BS and the relay is formulated. Two scenarios; namely instantaneous feedback after each redundancy packet, and feedback after multiple redundancy packets are investigated. We further extend the algorithms to multi-cell networks. Besides random network coding, IDNC based schemes are proposed as well. We show that significant improvements in transmission efficiency are obtained as compared to previously proposed ARQ and network-coding-based schemes. / QC 20110907

對於許多人而言，在寫作時要寫什麼題材、元素常另人傷透腦筋。本研究的目的為透過設計一個輔助敘事創作的電腦系統，來激發使用者在素材上的創造力，以期幫助使用者創作出一個題材新穎的故事。許多電腦輔助系統 (如 CAD, CAI, ITS等)，已經注意到協助創意思考的重要性。Liu (2000) 利用電腦運算將形狀重組，讓原本單一的形狀能延伸出許多不同的形狀，提供更多的變異性以激發使用者的創造力；因而本研究擬對於圖片、文字等以內容為主的元素，嘗試以Liu所提出的方式再生多樣的訊息；然而目前電腦要產生內容性的元素仍十分困難，因此人們對同樣一件事物的不同的想法，便成了提供變異內容的最佳資料庫，例如，Huang, Li, Wang & Chang (2007) 便利用腦力激盪的合作方式達成創意學習的目標。 本研究針對敘事創作，提出一個Picture-Attributed-Note (PAN) 架構，期望能激發使用者的敘事創意並協助其完成故事創作。在激發創意的部份，我們利用圖片、分類和筆記來呈現和記錄資料。其中分類筆記是以文字方式呈現，我們採用 Rabiger (2000) 所提出的 Character, Location, Object, Situation, Action, and Theme (CLOSAT) 來進行分類，藉圖片和分類資料的刺激，讓使用者能對故事中各樣的元素有更多的想法或聯想，以達到透過變異資料來激發創造力的目的。我們以PAN架構為基礎實作了一個電腦輔助系統來了解系統對使用者所產生的影響，並驗證所設計系統的有效性。本研究邀請了四位受測者來創作故事，其中一位在創作過程中沒有系統的輔助。在創作完畢後，四位受測者皆立刻觀看實施影音回溯來說明創作的過程。此資料最後用內容分析法，透過Chen (2002) 針對電腦系統所提出涵蓋 Conceptual, Operation, Perceptual和 Evaluation四個構面的編碼予以分析比較。實驗結果說明PAN 系統能幫助激發使用者尋找元素且不會改變使用者敘事創作的過程，同時PAN系統的介面設計能讓使用者能更專注於敘事創作的過程。 / It is difficult to find elements or topics for many people when they are writing a story. The goal of this research is to design a computer-aided system for narrative, which can stimulate user’s creativity on finding story elements. Many computer-aided systems (e.g. CAD, CAI, ITS etc.) have noticed the importance of assisting creative thinking. Liu (2000) reassembled a shape to provide different shapes for users, so their creativity can be stimulated through seeing more variables. This study uses pictures and texts as the elements and tries to use Liu’s method to reproduce more elements. However, it is difficult for computer to automatically generate pictures and texts that can deliver appropriate meanings and contexts. Nevertheless, people’s divergent thinking is a good source for computer to leverage. For instance, Huang, Li, Wang & Chang (2007) proposed a method to assist creative learning by brainstorming and cooperation. In this study, we focus on narrative creation and propose a Picture-Attributed-Note (PAN) framework to assist a writer’s creating process. We use picture and attributed notes to present and record story elements and to stimulate creativity. The attributed notes are presented by texts and in this study we utilize six attributes: Character, Location, Object, Situation, Action, and Theme (CLOSAT), which were proposed by Rabiger (2000), to categorize the text. We attempt to stimulate user’s creativity through the pictures and attributed notes and make the user think and associate elements for his/her story. In this study, we have implemented the PAN framework as a computer-aided system and conducted experiments to know how a user uses the PAN system for story writing. We invited four participants to create a story, one without the PAN system. When they completed their stories, they were asked to do video/audio protocol immediately. We used content analysis to analyze the data through four main categories: Conceptual, Operational, Perceptional and Evaluation (COPE) coding system, proposed by Chen (2002), to analyze and compare data. The analysis on our experimental results reveals that the PAN system can help stimulate user’s creativity and does not change the writer’s main creating process. In addition, the user interface of the PAN system can allow the user to concentrate more on the creating process.

Talet är något som många människor tar för givet, men för en del barn och vuxna är detta något som inte är lika självklart. Människor med språksvårigheter kan få hjälp och denna hjälp kan börja redan i förskolan. Alternativ och kompletterande kommunikation, AKK, är ett samlingsbegrepp av olika hjälpmedel som kompletterar talet. Teckenstöd och grafisk AKK är de två vanligaste AKK. Teckenstöd tecknar man med händerna samtidigt som du säger ordet. Grafisk AKK är bilder och symboler där man till exempel gör bildscheman över dagen. Tidigare forskning har visat att personal som gått en kurs inom alternativ och kompletterande kommunikation har börjat tänka mer på hur de kommunicerar med personer med språksvårighet och har också börjat använda sig mer av olika sorters AKK. Även de barn som inte har språksvårigheter gynnas av att använda alternativ och kompletterande kommunikation då det ger extra tydlighet i kommunikationen. Om alla barnen lär sig att använda alternativ och kompletterande kommunikation så kan de även använda denna i leken tillsammans med barn med språksvårigheter. I leken härmar barnen varandra både verbalt och icke-verbalt vilket innebär framsteg i kommunikationen.   I mitt examensarbete har jag intervjuat fyra förskollärare i olika kommuner i centrala och östra Värmland. I intervjuerna så framkom att arbetet med alternativ och kompletterande kommunikation varierar mycket, beroende på vilket behov som ansågs behövas. Inställningen till alternativ och kompletterande kommunikation var positiv bland alla de intervjuade men det upplevdes svårt att mäta förbättringen då detta är en lång process. Det framkom också att utbildning i kommunerna inom alternativ och kompletterande kommunikation inte var så stor men att det fanns en önskan bland samtliga förskollärare att lära sig mer om detta. / The spoken language is something that many people take for granted, but for some children and adults this is something that is not obvious. People with language difficulties can get help and this help can start already in preschool. Augmentative and alternative communication, AAC, is a collective concept of various aids that supplement the speech. There are two different types of AAC, aided systems and unaided systems. With unaided systems you use your body and hands to sign word while saying them out loud. Aided systems are pictures and symbols, for example, you create picture schedules throughout the day. Previous research has shown that staff who have taken a course in augmentative and alternative communication have started to think more about how they communicate with people with language difficulties and have also started to use more of different kinds of AAC. Even those children who do not have language difficulties benefits from using AAC as it provides extra clarity in communication. If all children learn to use AAC, they can also use this in the play together with children with language difficulties. In the play, the children mimic each other both verbally and non-verbally, which leads to progress in communication.  I have interviewed four preschool teachers in different cities in central and eastern Värmland. In the interviews, it became apparent that the way of working with AAC varies. The variation is caused by the individual extend to which the need for AAC is seen. The attitude towards Augmentative and alternative communication was positive among all interviewees. However, the measurement of improvements caused by AAC is being seen a challenge. The interviewees stated that the long period of time which is needed when using AAC makes it difficult to measure possible results. The preschool teachers participating in the interviews were of the opinion that education in their respective cities within AAC shows room for improvement and that there was a desire among them all to learn more about the concept.