WOOD THE POTENTIAL RESOURCE OF COMPLEX USE OF LIGNIN

The aim of the work is to investigate the use of existing wood waste, the most effective method of obtaining lignin and to create composite material made from renewable natural resources. The work looked at the current wider use of wood resources - construction, energy and chemical processing. The current waste from the use of wood - lignin is investigated. And the complex and rational use of this waste without waste. Experimentally, lignin was obtained with two methods, alkali and acid, from different Latvian tree species. Experimentally obtained composite samples with different compositions - alkali / acid lignin (binder) and leafy tree ash / chips (filler). Also, composite materials are considered at different proportions, where the percentage of both binders and fillers changes. Experimental samples were pressed at different temperatures.

CONTINUOUS INTEGRATION AND DELIVERY OF WEB APPLICATIONS

With the advent of DevOps practice, rapidly began evolve systems development life cycle shorting methods, such as continuous integration, testing and delivery, release automation and infrastructure as code methods. This methods, is similar to programming scripts which are used to automate a series of static steps to complete defined scenario. Often, the choice of used automation methods and tools depends on project and application complexity, which makes each case unique in its own way. The main goals of the paper are description of basic continuous integration and delivery methods for web based applications with real example using version control system, container virtualization and some auxiliary scripts, which developed by author and currently being successfully used on few real projects. In example used version control system, container virtualization and some auxiliary scripts.

COMPOSITION AND INHERITANCE MODEL COMPARISON

The inheritance seems to be the natural and the default solution of structuring the logic of software nowadays. But is it always the best option? Considering the increasing need for programming and the speed at which the projects are made, it’s inevitable that the requirements of a project will be changing many times and a lot of fundamental building blocks in the software will have to be redeveloped. The problem with inheritance is that with a change in functionality it may become necessary to rewrite huge amounts of old code or even end up duplicating existing functionality which only makes things worse in a long run. An excellent solution that can be used to avoid essentially getting stuck in situations like these is composition. The goal of the study is to analyze the pros and cons of composition and inheritance and make a conclusion about their correct usage.

WEBSITE CREATION FOR CONSTRUCTION SUPPLY COMPANY

Nowadays, a website can be considered a "face" of a company in a digital environment. To develop a successful and effective website, start with planning, first identifying the goals, wishes, needs and expectations of the organization from the target audience, as well as the product or service that the website will direct. The author's work has explored the websites of other building materials shops to evaluate and understand how to make a website better for your company. An employee survey was conducted to find out if a website was needed. As a result, the authors of the work created a model for their company's website.

OBJECTS DURABILITY UNDER PRESSURE DEPENDING ON BUILD STRUCTURE

Pētījumā, izmantojot 3d printeri, tika printētas vienāda izmēra sagataves ( 30mm x 30mm x 12mm), taču ar dažādām uzbūves struktūras pildījumiem (zvaigzne, trīsstūtis, taisnstūris, sešstūris u.c) Tad sagataves tika ievietotas spiedes mašīnā, lai pārbaudītu to mehānisko izturību. Pētījuma mērķis ir noskaidrot, kurš no struktūras uzbūves veidiem ir visizturīgākais zem spiedes mehāniskas ietekmes uz sagatavi.Tika izmantotas šādas uzbūves struktūras – Zvaigzne, trīsstūris, taisnstūris, režģis, kubs, koncentriski apļi, sešstūris un astoņstūris. Pētījuma tika noskaidrots maksimālais spēka daudzums ņūtonos, kuru sagatave spēja izturēt. Kategorijā ar 20% aizpildījumu visizturīgākā bija sagatave ar zvaigznes struktūras uzbūvi. No trim mēģinājumiem vislielākais sasniedzamais spēks bija 11300N. Vidējais maksimālais spēks sasniedza 11066 N lielu spēku. Otra izturīgākā bija sagatave ar režģa struktūras uzbūvi. No trim mēģinājumiem vislielākais sasniedzamais spēks bija 10200N liels spēks. Vidējais maksimālais spēks sasniedza 9486N. Trešā izturīgākā sagatave bija ar sešstūra struktūras uzbūvi. No trim mēģinājumiem vislielākais sasniedamais spēks bija 8910N liels spēks. Vidējais maksimālais spēks no trim mēģinājumiem sasniedza 8736N lielu spēku.

DETERMINATION OF HABITAT 6270*_3 PERMITTED DRAINAGE RATE

Amelioration has dramatically altered the distribution of semi-natural grasslands in Latvia and as a result of the drainage, and the ocurrance of humid grassland habitats has decreased sharply. The aim of the paper was to identify drainage rate for habitat 6270*_3 ecohydrological requirements which is necessary for its successful management and long-term existence. The work looked at 15 equally managed (extensively grazed and/or mowed) perennial, natural grasslands at different levels of drainage resulting in various quality states. To reveal the most habitat-preserving drainage rate, for each site of the habitat 6270*_3 a decrease of groundwater table was identified. As a result a rate that meets ecohydrological requiremets is procured.

EXPERIMENTAL STUDY OF TACTICAL AND TECHNICAL CHARACTERISTICS OF THE ELECTRIC DRIVE OF A STRIKEBALL WEAPON.

Electro-pneumatic actuator is an accurate external modulation of combat weapons, which is used for tactical games and development of combat skills. Electro-pneumatic drive (AEG) and its advantage in high speed of fire were investigated in the experiment and the number of its shots exceeds even the number of combat weapon's shots. The other advantages are the large number of shots on a standard battery and miniature design, because weight and size are more modulation requirement than necessity.

EVALUATION OF RESULTS OF SARKANDAUGAVA DEGRATED TERRITORY

The historically polluted areas of Sarkandaugava are one of the most polluted sites in Latvia that are included in the register of contaminated and potentially polluted areas. The Sarkandaugava territories have historically been used for the storage and handling of oil products. The remediation process was used: liquidation of floating oil product with double pumping and vacuum pumping method, and elimination of residual pollution by microbiological method.

MATHEMATICAL MODELLING OF THE ANALYTICAL AND NUMERICAL SOLUTION OF NON-STATIONARY INITIAL-VALUE PROBLEMS BY MAPLE SOFTWARE.

With the passage of time and the development of technology, humanity is exploring new unknown problems that require complex analytical and numerical mathematical solutions. Due to their complexity differential equations are often used for this purpose. The aim of this work is to solve mathematical models of initial value problems of ordinary differential equations using the analitical method and numerical solution using MAPLE software. Also authors have provided general information about differential equations and diferent ways how they can be solved. As a result have been created two mathematical models which describe process of Determination of the cooling time of a shot animal and decomposition of the radioactive substance. Similar methods are also used to determine the age of objects as well

MICROSTRUCTURING IN PLATINUM AND STAINLESS STEEL MATERIAL USING PICOSECOND Nd:YAG LASER

The number of products manufactured in micro- and nano-size is increasing every year. In electronics, medicine, biology and other industries, because of the rapid development of technologies, is possible to produce new or already used products in very small sizes, maintaining or even improving the efficiency of the product or giving an opportunity to use them for new purposes. Currently available pico- and femtosecond lasers ensure the production of such products in very small sizes. In this study, the treatment of platinum and stainless steel using a picosecond Nd:YAG laser with a wavelength of 1064nm, was considered. The obtained results for the laser ablation process of these materials will be useful for further research in the field of laser microprocessing.