This is a thesis for the degree of filosofie licentiat (a Swedish degree between Master of Science and Ph.D.). It comprises three articles, all treating variations and augmentations of suffix trees, and the capability of the suffix tree data structure to efficiently capture similarities between different parts of a string. The presented applications are in the areas of data compression and patt...

It is experimentally shown that using organic materials of high nonlinear refractive index dissolved in a saturable-absorber solution permits femtosecond-pulse compression in a simple colliding-pulse mode-locked laser employing cavity-mirror dispersion adjustment.

Digital images are often used in several domains. Large amount of data is necessary to represent the digital images so the transmission and storage of such images are time-consuming and infeasible. Hence the information in the images is compressed by extracting only the visible elements. Normally the image compression technique can reduce the storage and transmission costs. During image compres...

Arithmetic coding is used in many compression techniques during the entropy encoding stage. Further compression is not possible without changing the data model and increasing redundancy in the data set. To increase the redundancy, we have applied index based byte-pair transformation (BPT-I) as a pre-processing to arithmetic coding. BPT-I transforms most frequent byte-pairs (2-byte integers). He...

The authors studied the contrast sensitivity function in 40 patients with pituitary adenoma. It seems to be a good index of compression of the visual pathway in this disease, but it lacks specificity and it cannot be used alone.

We propose a new compression algorithm that is tailored to database applications It can be applied to a collection of records and is especially e ective for records with many low to medium cardinality elds and numeric elds In addition this new technique sup ports very fast decompression Promising application domains include decision sup port systems DSS since fact tables which are by far the la...

BACKGROUND thrombo-embolic complications are important causes of morbidity and mortality after acute stroke. Anticoagulant prophylaxis is contraindicated in intracerebral haemorrhage and not recommended in acute ischaemic stroke because of increased risk of cerebral haemorrhage. Graduated elastic compression stockings are a simple alternative but are not widely used in stroke patients, perhaps ...

PURPOSE To assess retrospectively the effect of the Joint Photographic Experts Group 2000 (JPEG2000) compression ratio on the quality of thin-section computed tomographic (CT) images. MATERIALS AND METHODS In this institutional review board-approved investigation (protocol 238/2004), thin-section CT images were subjected to irreversible JPEG2000 compression by using five compression ratios (3...

The size of electronic data is currently growing at a faster rate than computer memory and disk storage capacities. For this reason compression appears always as an attractive choice, if not mandatory. However space overhead is not the only resource to be optimized when managing large data collections; in fact data turn out to be useful only when properly indexed to support search operations th...

In this paper, we propose a novel reversible data hiding framework to hide secret data into a binary codestream of VQ indices invertibly, in which matrix encoding is used to efficiently embed secret data, and error correction coding (ECC) is employed for lossless restoration of the marked codestream at the receiver side. Due to the unchanged structure of the codestream during the embedding proc...