Preservation of natural patterns visual expression peculiarities and development planning in the peri-urban areas of contrasting topography

The physical sprawl of a town is one of the main factors having an influence on periurban functional development and economic expansion. After Lithuania became a member of the EU, the biggest towns and especially the capital Vilnius have undergone considerable changes in the landscape of peri-urban areas: agricultural functions are gradually changed by urban functions, what makes negative anthropogenical influence on the landscape character and its ecological stability. The general plan for Vilnius even up to the year 2005 formulated the concept of city greenbelt. Unfortunately, this concept remained unrealized because of juridical assumptions and insufficient collaboration between neighbourhood municipalities. Despite this fact, the problems of landscape preservation and urban development in peri-urban areas still need further scientific research. Practice of landscape inventory, assessment and planning in Lithuania is commonly confined to general physical or visual landscape characteristics and their description. Fundamental landscape classification based on natural and cultural morphology is the mainstream in the country. Applied, perceptional classification of landscape refer just to visual landscape characteristics and often do not consider the morphology of the natural landscape patterns. In practice, this type of classification is used as a tool for landscape planning in recreational or protected territories, such as national or regional parks. In the country, the territory planning practice mostly refers to ecological landscape classification, where the main aspects are processes, analysing circulatory relations. The aspect of landscape in urban development plans at the district level takes only a common descriptions and are not orientated in an integrative way concerning urban development. Obviously Lithuanian theory and practice of peri-urban planning needs a complex tool for landscape and urban development, which leads to the integrated character-based planning, cited on physical, functional, visual and mainly individually perceived natural features of the landscape. The efficiency of landscape planning mostly depends on the way of landscape classification. The review of landscape classification methods is the main issue for the background of this report

Modeling and simulations of beam stabilization in edge-emitting broad area semiconductor devices

A 2+1 dimensional PDE traveling wave model describing spatial-lateral dynamics of edge-emitting broad area semiconductor devices is considered. A numerical scheme based on a split-step Fourier method is presented and implemented on a parallel compute cluster. Simulations of the model equations are used for optimizing of existing devices with respect to the emitted beam quality, as well as for creating and testing of novel device design concept

Metropolitan centres. Urban fringe landscape protection and planning / Metropolinių centrų priemiesčio kraštovaizdžio apsaugos ir planavimo klausimai

The paper considers requirements of the European Landscape Convention as well as obligations of Lithuania in the field of implementation of such requirements. Furthermore, it discusses advancing general and concrete political and legal tools, which are imposed on the national landscape protection, regulation and planning. Landscape protection is proposed to orient towards protection and maintenance of characteristic features, while sustainable development is achieved via landscape planning. The important problems of metropolitan centre fringe landscape formation are analysed. While preparing general plans of cities and district municipalities, district landscape plans give insufficient attention to preservation of landscape characteristics. That is the reason tools for integrated landscape protection and urban development have been proposed in the paper as well as ways for their implementation into the national planning practice. With the help of these tools, land proprietors and urban planners will better understand the influence of proposed decisions on landscape and determine the most suitable urban development forms in the metropolitan fringes. Sustained metropolitan fringe development should be supported by the criterion of landscape protection. It has to implement life quality aspirations of people living both in cities and districts. Santrauka Svarstomi Europos kraštovaizdžio konvencijoje keliami reikalavimai, Lietuvos įsipareigojimai juos įgyvendinti tobulinant bendro ir konkretaus pobūdžio politines ir teisines priemones, skirtas šalies kraštovaizdžiui apsaugoti, tvarkyti ir planuoti. Straipsnyje kraštovaizdžio apsaugą siūloma orientuoti į būdingų kraštovaizdžio ypatybių išsaugojimą ir palaikymą, kai tvarios plėtros siekiama planuojant kraštovaizdį. Aptariamos opios metropolinių centrų priemiesčio kraštovaizdžio formavimo problemos. Rengiant miestų ir rajonų savivaldybių bendruosius planus, rajoninius Kraštovaizdžio planus, priemiesčio kraštovaizdžio charakterio išsaugojimo klausimai nepakankamai respektuojami, todėl siūlomas integruotų kraštovaizdžio apsaugos ir užstatymo plėtros priemonių sukūrimas ir jų įdiegimas į šalies planavimo praktiką. Taikydami šias priemones žemės valdytojai ir projektuotojai geriau suprastų siūlomų sprendinių poveikį kraštovaizdžiui, nustatytų tinkamiausias priemiesčio užstatymo formas, jas harmoningai įterpdami į kraštovaizdinį kontekstą. Kraštovaizdžio apsaugos kriterijumi paremta tvari priemiesčių plėtra turėtų tapti priemone, padedančia įgyvendinti tiek miesto, tiek rajono gyventojų gyvenimo kokybės siekius. Reikšminiai žodžiai: didmiestis, priemiestis, metropolinis arealas, metropolizacija, tvari plėtra, kraštovaizdžio charakteri

Kraštovaizdžio vizualinės raiškos savitumo apsauga didmiesčio priemiestinėse teritorijose/Preservation of landscape visual expression identity in peri-urban areas of metropolis

In the context of urban expansion the preservation of the individuality of landscape visual expression in peri-urban areas is becoming a very relevant but at the same time hard task. Practice of landscape planning is commonly confined to general physical or visible landscape characteristics and their description. Urban development in peri-urban areas is usually confined to functional or structural planning criteria. Thereby, the Lithuanian theory and practise of territory planning really needs a method of landscape and urban development which leads to an the integrated landscape assessment and planning, based on physical, visible and mainly individually perceived features of landscape visual expression. Santrauka Didmiesčių urbanistinės plėtros sąlygomis priemiesčio teritorijų kraštovaizdžio vizualinės raiškos individualumo išsaugojimas tampa aktualiu, bet sunkiai sprendžiamu uždaviniu. Teritorijų planavimo praktikoje vertinant kraštovaizdį dažniausiai apsiribojama tik bendrinių kraštovaizdžio fizinių ar regimųjų savybių aprašymu. Užstatymo plėtra priemiesčio zonose paprastai remiasi tik funkciniais ir struktūriniais planavimo kriterijais. Lietuvos teritorijų planavimo teorijoje ir praktikoje pasigendama kraštovaizdžio bei užstatymo plėtros vertinimo metodo, kuris būtų orientuotas į integruotą kraštovaizdžio vertinimą bei planavimą, paremtą kraštovaizdžio fizinių, regimųjų savybių savita, žmogaus suvokiama vizualine raiška. First Published Online: 22 May 2013 Reikšminiai žodžiai: urbanistinė plėtra, priemiestis, kraštovaizdžio charakteris, jautrumas, suvokimas ir vizualinė raiška

Modeling and Simulations of Beam Stabilization in Edge-Emitting Broad Area Semiconductor Devices

A 2+1 dimensional PDE traveling wave model describing spatial-lateral dynamics of edge-emitting broad area semiconductor devices is considered. A numerical scheme based on a split-step Fourier method is presented and implemented on a parallel compute cluster. Simulations of the model equations are used for optimizing of existing devices with respect to the emitted beam quality, as well as for creating and testing of novel device design concepts