The telencephalon is the most highly evolved region of the vertebrate central nervous system (CNS). The major structures of the telencephalon - the cortex and basal ganglia – derive from the dorsally positioned pallium and the ventrally positioned subpallium, respectively. Differences in morphology, gene expression, and connectivity permit a subdivision of the developing telencephalon into domains that give rise to discrete regions of the adult brain. In mammals, the ventral region of the developing telencephalon can be subdivided into the medial (MGE) and lateral (LGE) ganglionic eminences. The dorsal midline cells give rise to the choroid plexus, and cells in the more lateral domain, the dorsal pallium, give rise to the cerebral cortex. Genetic studies have provided evidence that crossregulatory interactions between transcription factors contribute to the regionalization of the telencephalon. Less is known, however, about the secreted signals that induce the initial dorsoventral character of telencephalic cells. Sonic hedgehog (SHH) is required for the specification of ventral character along the entire anteroposterior (AP) extent of the developing CNS, including the telencephalon. We show that WNT activity imposes an early generic dorsal telencephalic character and that Fibroblast Growth Factor (FGF) act sequentially, and in concert with WNT, to specify cells of definitive dorsal telencephalic character. We also show that retinoic acid (RA)-mediated signaling induces intermediate character in telencephalic cells, and that FGFs maintain cells of ventral character by opposing RA activity. The following model emerges from these findings. At gastrula stages, most or all prospective telencephalic cells become specified as ventral cells in response to node-derived SHH signals. At neural fold- and early neural plate stages, cells in the prospective dorsal and intermediate regions of the telencephalon cells are exposed to WNT signaling that induce a generic dorsal character. The head ectoderm adjacent to the telencephalon then starts to express the retinoic acid producing enzyme, Raldh3, thus exposing telencephalic cells to RA signals. At the same time prospective dorsal cells start to express WNT signals. RA signaling appears to promote the generation of intermediate/prestriatal cells, whereas WNT signal suppress the actions of RA on dorsal cells, which therefore maintain their dorsal character. From the neural plate stage, prospective ventral 6 telencephalic cells are exposed to FGF8 derived from the anterior neural ridge, and FGF8 maintains ventral telencephalic character by opposing the influence of RA signals in ventral cells. At early neural tube stages, the domain of Fgf8 expression expands dorsally and FGF signals derived from the dorsal midline region induce definitive dorsal/precortical cells. In the intermediate region of the telencephalon cells evade high levels of WNT and FGF signals, resulting in an environment in which RA signaling is able to induce prestriatal character.

This thesis presents a theoretical discussion of meaning creation in general, and interpretive functions of English adjectives in particular. The discussion rests on a dynamic view of meaning and interpretation, according to which there are no fixed linguistics meanings – not even for single lexemes. Instead of symbolising meaning in a more or less static and ‘eternal’ fashion, linguistic items are assumed to effect the creation of meaning and to shape meaning dynamically in the particular communicative event at hand, from some kind of underlying ‘raw material’ (also referred to as purport and schemas). It is suggested that the interpretive functions of linguistic items – that is the effects that such items have in the creation of meaning – may be approached in two main ways, namely from the formal and from the semantic point of view respectively. Effects triggered by the form of a certain item are referred to as formal interpretive functions (FIFs), and effects prompted by the meaning created for the form are referred to as semantic interpretive functions (SIFs). FIFs are claimed to be the same for all items – namely to activate, delimit and shape underlying purport and schemas – whereas SIFs are said to differ between items, and also for one and the same item on different occasions of use. It is furthermore suggested that FIFs affect the creation of meaning for the relevant item itself, whereas SIFs affect the creation of meaning for other items, on any level of conceptual organisation. For instance, a form such as tall typically activates and delimits purport and schemas to do with some kind of extension (notably in space), thereby shaping a basic word meaning tall. The meaning thus created may in turn affect other meaning in the larger context. For instance, tall, as created in default interpretation of a tall man entered the room, affects the meaning of the noun phrase a tall man as a whole, in that it specifies the interpreter’s conception of a certain something that entered a specific room. In this case, the relevant SIF is thus to specify. Other SIFs suggested for adjectives are kind identification, element identification, identity provision and stipulation. The aim of the thesis is two-fold: on the one hand to outline a suggestive theory of meaning creation and interpretive function in general, and, on the other hand, to present a theoretical discussion of adjective functions in particular, with the ultimate goal of providing a general framework from which more specific models for in-depth empirical research can be obtained.

This dissertation consists of 3 essays In the first essay, A Simple Variable Selection Technique for Nonlinear Models, written in cooperation with Timo Teräsvirta and Rolf Tschernig, I propose a variable selection method based on a polynomial expansion of the unknown regression function and an appropriate model selection criterion. The hypothesis of linearity is tested by a Lagrange multiplier test based on this polynomial expansion. If rejected, a kth order general polynomial is used as a base for estimating all submodels by ordinary least squares. The combination of regressors leading to the lowest value of the model selection criterion is selected.  The second essay, Modelling and Forecasting Economic Time Series with Single Hidden-layer Feedforward Autoregressive Artificial Neural Networks, proposes an unified framework for artificial neural network modelling. Linearity is tested and the selection of regressors performed by the methodology developed in essay I. The number of hidden units is detected by a procedure based on a sequence of Lagrange multiplier (LM) tests. Serial correlation of errors and parameter constancy are checked by LM tests as well. A Monte-Carlo study, the two classical series of the lynx and the sunspots, and an application on the monthly S&amp;P 500 index return series are used to demonstrate the performance of the overall procedure. In the third essay, Forecasting with Artificial Neural Network Models (in cooperation with Marcelo Medeiros), the methodology developed in essay II, the most popular methods for artificial neural network estimation, and the linear autoregressive model are compared by forecasting performance on 30 time series from different subject areas. Early stopping, pruning, information criterion pruning, cross-validation pruning, weight decay, and Bayesian regularization are considered. The findings are that 1) the linear models very often outperform the neural network ones and 2) the modelling approach to neural networks developed in this thesis stands up well with in comparison when compared to the other neural network modelling methods considered here. / <p>Diss. Stockholm : Handelshögskolan, 2002. Spikblad saknas</p>

Formal verification techniques are growing increasingly vital for the development of safety-critical software and hardware in practice. Techniques such as requirements-based design and model checking for system verification have been successfully used to verify systems for air traffic control, airplane separation assurance, autopilots, CPU logic designs, life-support, medical equipment, and other functions that ensure human safety. Formal behavioral specifications written early in the system-design process and communicated across all design phases increase the efficiency, consistency, and quality of the system under development. We argue that to prevent introducing design or verification errors, it is crucial to test specifications for satisfiability. We advocate for the adaptation of a new sanity check via satisfiability checking for property assurance. Our focus here is on specifications expressed in Linear Temporal Logic (LTL). We demonstrate that LTL satisfiability checking reduces to model checking and satisfiability checking for the specification, its complement, and a conjunction of all properties should be performed as a first step to LTL model checking. We report on an experimental investigation of LTL satisfiability checking. We introduce a large set of rigorous benchmarks to enable objective evaluation of LTL-to-automaton algorithms in terms of scalability, performance, correctness, and size of the automata produced. For explicit model checking, we use the Spin model checker; we tested all LTL-to-explicit automaton translation tools that were publicly available when we conducted our study. For symbolic model checking, we use CadenceSMV, NuSMV, and SAL-SMC for both LTL-to-symbolic automaton translation and to perform the satisfiability check. Our experiments result in two major findings. First, scalability, correctness, and other debilitating performance issues afflict most LTL translation tools. Second, for LTL satisfiability checking, the symbolic approach is clearly superior to the explicit approach. Ironically, the explicit approach to LTL-to-automata had been heavily studied while only one algorithm existed for LTL-to-symbolic automata. Since 1994, there had been essentially no new progress in encoding symbolic automata for BDD-based analysis. Therefore, we introduce a set of 30 symbolic automata encodings. The set consists of novel combinations of existing constructs, such as different LTL formula normal forms, with a novel transition-labeled symbolic automaton form, a new way to encode transitions, and new BDD variable orders based on algorithms for tree decomposition of graphs. An extensive set of experiments demonstrates that these encodings translate to significant, sometimes exponential, improvement over the current standard encoding for symbolic LTL satisfiability checking. Building upon these ideas, we return to the explicit automata domain and focus on the most common type of specifications used in industrial practice: safety properties. We show that we can exploit the inherent determinism of safety properties to create a set of 26 explicit automata encodings comprised of novel aspects including: state numbers versus state labels versus a state look-up table, finite versus infinite acceptance conditions, forward-looking versus backward-looking transition encodings, assignment-based versus BDD-based alphabet representation, state and transition minimization, edge abbreviation, trap-state elimination, and determinization either on-the-fly or up-front using the subset construction. We conduct an extensive experimental evaluation and identify an encoding that offers the best performance in explicit LTL model checking time and is constantly faster than the previous best explicit automaton encoding algorithm.

The traffic sign detection and recognition system is an essential part of the driver warning and assistance systems. In this thesis, traffic sign recognition system is studied. We considered circular, triangular and square Turkish traffic signs. For detection stage, we have two different approaches. In first approach, we assume that the detected signs are available. In the second approach, the region of interest of the traffic sign image is given. Traffic sign is extracted from ROI by using a detection algorithm. In recognition stage, the ring-partitioned method is implemented. In this method, the traffic sign is divided into rings and the normalized fuzzy histogram is used as an image descriptor. The histograms of these rings are compared with the reference histograms. Ring-partitions provide robustness to rotation because the rotation does not change the histogram of the ring. This is very critical for circle signs because rotation is hard to detect in circle signs. To overcome illumination problem, specified gray scale image is used. To apply this method to triangle and square signs, the circumscribed circle of these shapes is extracted. Ring partitioned method is tested for the case where the detected signs are available and the region of interests of the traffic sign is given. The data sets contain about 500 static and video captured images and the images in the data set are taken in daytime.

<p>This thesis emphasizes on surveying the state-of-the-art in software requirements specification with a focus on, autonomic, self-adapting software systems. Since various requirements are brought forward accord with environments, modeling requirements for adaptive software systems may be changed at run-time. Nowadays, Keep All Objectives Satisfied (KAOS) is an effective method to build goal model. Various manipulations, such as change, remove, active and de-active goals, appear new goals, could mediate conflicts among goals in adaptive software system. At specification time, specifications of event sequences to be monitored are generated from requirements specification.</p>

We have previously shown that the arcuate organization of cell fates within the ventral midbrain critically depends upon the morphogen, Sonic Hedgehog (SHH), which is secreted from a signaling center located along the ventral midline, called the floor plate (FP). Thus, it is ultimately the specification of the FP that is responsible for the patterning and specification of ventral midbrain cell fates. Interestingly, we have found that the chick midbrain FP can be divided into medial (MFP) and lateral (LFP) regions on the basis of gene expression, mode of induction and function. Overexpression of SHH alone is sufficient to recapitulate the entire pattern of ventral cell fates, although remarkably it cannot induce MFP, consistent with the observation that the MFP is refractory to any perturbations of HH signaling. In contrast, overexpression of the winged-helix transcription factor FOXA2/HNF3[beta]robustly induced the MFP fate throughout ventral midbrain while blocking its activity resulted in the absence of the MFP. Thus, by analyzing the differences between SHH and FOXA2 blockade and overexpression, we were able to attribute functions to each the LFP and the MFP. Notably, we observed that FOXA2 overexpression caused a bending of the midbrain neurepithelium that resembled the endogenous median hinge-point observed during neurulation. Additionally, FOXA2 misexpression led to a robust induction of DA progenitors and neurons that was never observed after SHH expression alone. In contrast, we found that all other ventral cell types required HH signaling directly, at a distance and early on in the development of the midbrain when its tissue size is relatively small. Additionally, HH blockade resulted in increased cell-scatter of the arcuate territories and in the disruption of the regional boundaries between the ventral midbrain and adjacent tissue. Thus, we bring new insight into the mechanism by which midbrain FP is specified and ascribe functional roles to its subregions. We propose that while the MFP regulates the production of dopaminergic progenitors and the changes in cellshape required for bending and shaping the neural tube, the LFP appears to be largely responsible for cell survival and the formation of a spatially coherent pattern of midbrain cell fates. / text

The purpose of this project was to create a requirement repository using a methodology, which is being developed in the department of Information Systems of Kaunas University of Technology. The implementation would raise the methodology to the higher level enabling its use in practice. Using the implementation one could either prove or disprove the main idea behind the methodology - the simplification of the stakeholder-analyst dialogue during the IS requirements specification. For that, the experiment was conducted. The purpose of the experiment was to specify requirements for the real-world IS using implemented requirement repository, and compare the results to other similar software.

Magistro darbe tiriama paliktų biologinei įvairovei medžių plyno kirtimo biržėse būklė ir išlikimas. Darbo objektas – plyno kirtimo biržės ir jose palikti biologinės įvairovės medžiai. Darbo tikslas – nustatyti plynose kirtavietėse paliekamų biologinės įvairovės medžių būklę, rūšinę sudėtį, kiekį ir pasiskirstymą bei išlikimą kirtavietėje. Darbo metodika – atliekant tyrimą, dėmesys buvo kreipiamas į du skirtingus parametrus. Pirmiausia buvo išsiaiškintas atskirų medžių atsparumas aplinkos poveikiams, priklausomai nuo jų individualių savybių. Kitas tyrimas, kuriame buvo apskaičiuota žuvusių medžių dalis kirtavietėje, priklausomai nuo kirtavietės parametrų ir medžių išsidėstymo joje. Darbo rezultatai – Plynose kirtavietėse vidutiniškai paliekama 11 medžių hektare, iš kurių per pirmuosius šešerius metus 14 procentų žūsta. Didėjant kirtavietės dydžiui bendras išlikimo procentas mažėja. Geriau išlieka grupėmis paliekami medžiai nei medžiai paliekami pavieniui. Didelę reikšmę medžių išlikimui turi vėjas - du trečdaliai žuvusių medžių žuvo dėl vėjo, buvo išversti arba nulaužti. Didžiausią poveikį vėjas turi medžiams, kurių paviršinė šaknų sistema, ir medžiams, kurių storio ir aukščio santykis mažesnis. Didėjant atstumui nuo kirtavietės krašto, dėl didesnio vėjo poveikio, medžių išlikimas mažėja. Atskirų medžių rūšių išlikimas priklauso nuo augavietės atitikimo medžių rūšiai ir paliekamų medžių individualių parametrų. Atrenkant paliekamus biologinei įvairovei medžius didesnis... [toliau žr. visą tekstą] / The master thesis presents evaluation of the trees condition and ability to survive, which are left for biological diversity in the clear cutting areas. Object of the work – trees left for biological diversity in clear cutting areas Aim of the work – to evaluate the condition, variety, quantity and layout of the trees, left for biological diversity in clear cutting areas. Methods of work- attention were paid to two different indicates: first, it has been investigated trees ability to resist environmental factors, depending on individual aspects of each tree. Second, it has been investigated area of coppice, where it was examined fraction of dead trees depending of trees layout and different factors in the coppice. Result of the work – there are approximately eleven trees left in each hectare and 14 percent of them do not survive during the first 6 years. The more the coppice expands the less possibility of tree to survive. The trees are more likely to survive when they are left in groups rather than on their own. The wind has important implication to the trees; two thirds of the trees get destroyed by the wind. The trees that are mostly in danger due to the wind are the ones that have roots spread out close to the ground surface and which have a reduced diameter and height ratio. Trees that are in the middle of the coppice have an increased risk to die from wind. Various trees survive depending on the type of the tree specification and its environmental... [to full text]

This work presents business process analysis methodology which consists of presentation of the business processes created on the ground of the Resource Event Agent model by means of Piece–Linear Aggregate approach. The aggregate specification is analyzing using first order predicate logic while checking correctness by resolution method using logic programming based language Prolog. The work is concluded with concrete example of analysis of Resource Event Agent model based business process using the aggregate approach. The novelty of this work PLA (Piece-Linear Aggregate) model and the software tools, created on the ground of PLA (Piece-Linear Aggregate), are used the first time for business processes analysis that is defined using REA formalism. The use of such integrated models allows performing the automated analysis of general and individual properties (completeness, deadlock freeness, termination or cyclic behavior, boundedness) of defined business processes. The main results are achieved: • The methodology, that consists of presentation of the business processes created on the ground of the Resource Event Agent model by means of Piece–Linear Aggregate approach. • Verification and validation of general and individual properties by using PLA and PROLOG language approach designed system that executes the analysis of aggregate specification. • Implementing internal accounting controls as constraints in relational algebra, SQL and PROLOG language. • Concrete... [to full text]