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Influence of Veneer Density on Plywood Thickness and Some Mechanical Properties
2021
Kūliņš, Laimonis | Meija, Anete | Roziņš, Rihards | Liepa, Kārlis Hermanis | Spulle, Uldis
It has been common knowledge that as the density of wood increases, the mechanical properties also improve. In turn, the density of wood depends on many factors, including the wood moisture content, location and cross-section in the trunk, the type of treatment and the parameters of technological processes. There is a great deal of research reported in the scientific literature on the effect of solid wood density on mechanical properties for different wood species as well as for structural timber. However, no research data can be found related investigation of the influence of veneer density on the properties of the birch plywood. In the present study, researching the properties of 7-ply birch plywood (thickness 9 mm), it was concluded that as the density of veneers increases, the bending properties of plywood in the direction of wood fibers (covered veneers) increases. When determining the plywood gluing quality, similar tendencies have been observed. For plywood with a lower density in all veneer plies the gluing quality (tensile-shear test) for perpendicular wood fiber veneers increases in the direction from the symmetry axis or middle veneer to the plywood outer plies, which can be explained by the fact that the outer plies become denser at the time of the hot pressing process. The results of the study will allow birch plywood manufacturers in direct production, sort veneers by density, to produce plywood with very predictable gluing quality, plywood thickness and mechanical properties in bending.
Show more [+] Less [-]The Significance of “Green” Skills and Competencies Making the Transition Towards the “Greener” Economy
2021
Nikolajenko-Skarbalė, Jelena | Viederytė, Rasa | Šneiderienė, Agnė
Climate change and environmental deterioration have been recognized as global drivers of change, and the shift to the “greener” economy is the key to sustainable development. The green economy is a priority field for developing and developed economies. However, as the authors of the publication have realised, there is no consensus about the meaning of the green economy and “green” jobs, that is why an uncertainty as in measurement of economic trends and an impact of it, as well as in what skills and competencies should be assigned to the “green” ones, arises. The new “green” processes and technologies are arising in a progressive trend, that is why it is important to ensure there are properly skilled candidates with appropriate “green” skills and competencies on the labour market, as well as to prepare fresh graduates with the “green” skills that will meet requirement of both, the recent and the future companies, especially operating in the “green” sector. In the framework of “SB Bridge” project an online survey was conducted by interviewing the “green” companies to identify which skills and competencies are needed for “green” jobs recently, and whether candidates and fresh graduates are enough with the “green” skills and competencies for fruitful engagement to “green” jobs. As the survey identified, fresh graduates and candidates for “green” jobs lack technical and (or) mechanical knowledge, IT skills, as well as experience and ability to work independently and in the team to resolve arising problems.
Show more [+] Less [-]Status of the Precision Beekeeping Development in Latvia
2021
Zacepins, Aleksejs | Kviesis, Armands | Komasilovs, Vitalijs | Brusbardis, Valters | Kronbergs, Janis
Information and communication technologies are part of almost any branch of human lives. During the last decade also beekeeping joined the direction of application of IT tools and solutions and precision beekeeping was defined. Still in the beekeeping many operations and observations are completed manually, and there is a potential to switch to the digital realisation. Information technologies can be used in the beekeeping to partly support the beekeepers by implementation of automatic or semi-automatic solutions for bee colony remote monitoring, apiary record making and other actions. The aim of this paper is to make a summary of the usage of information technology tools by the beekeepers in Latvia, summarizing precision beekeeping development status and conclude about its future development potential. To achieve this aim, in cooperation with Latvian Beekeepers Association, a beekeepers survey was conducted. More than 200 beekeepers shared thoughts and opinions about their application of information and communication technologies for monitoring the bee colonies and apiary management. The summary of the survey conducted is described in this study.
Show more [+] Less [-]Resilience of Milk Supply Chains during and after the COVID-19 Crisis in Latvia
2021
Pilvere, Irina | Upīte, Ilze | Muska, Aina | Zdanovskis, Kristaps | Nipers, Aleksejs | Janmere, Lana
The impacts of the COVID-19 pandemic on national economies are characterized as the worst economic turmoil in recent years, as economic growth slowed to the level of the 2008 global financial crisis. At the end of 2019 and the beginning of 2020, economic growth surveys did not project that the novel virus could have a negative impact on economic growth. As a result of the rapid spread of the virus and the increase in the number of infection cases, national governments took strict measures to limit the spread of the virus, which led to a significant deterioration in the economic situation in all industries of the economy. Agriculture plays an important role in providing food to the country’s population, yet the pandemic made a negative impact on sales volumes and prices in the domestic and international markets. The research aims to assess the impacts of the pandemic on milk supply chains in Latvia and come up with solutions to stabilizing the situation in the dairy sector. The national restrictions to combat the pandemic also hampered the dairy sector concerning the sale of raw milk and finished products in foreign markets, thereby leading to overproduction and stockpiling of the finished products, price dumping and a significant decrease in milk purchase prices to or below the production cost level for many dairy farms. Although there is no indication that the pandemic would lead to a decrease in the numbers of livestock and farms or output in early 2021, it is too early to assess the overall impact of the pandemic on dairy farming, as uncertainty over the duration of pandemic restrictions is a major risk to farm survival. The operation of the dairy sector was stabilized by means of the support provided by the government, as well as the farms’ accumulated financial and feed resources. In order to identify future challenges for milk supply chains, the research performed an analysis of operational risks for milk producers and processors to identify the most important risks and design recommendations for their elimination. The longer there is uncertainty about the return of the dairy sector to pre-pandemic output levels, the more likely it is that the pandemic is going to lead to a decrease in the numbers of dairy livestock and farms.
Show more [+] Less [-]The Influence of Technological Peculiarities on Fermented Sausages’ Quality and Sensory Properties
2021
Gramatina, Ilze | Sauka, Janis | Semjonovs, Aleksandrs | Strode, Sintija | Straumite, Evita
Fermentation is one of the ancient technological processes used in food production which influences the shelf-life of meat and meat products, also significantly affects the sensory properties like aroma and flavour. The objective of the present study was to evaluate the elaborated technology for a new fermented sausage production on the product quality and sensory properties. Sausages were produced by the standard technology using glucono-delta-lactone or starter culture. The drying of samples differs from 3 to 4 weeks at the same conditions; samples were dried for 4 weeks which produced with the starter culture, and 3 weeks which produced with glucono-delta-lactone. The sausages were tested at the end of the production, analysing pH, water activity, moisture and salt content, as well as the presence of Listeria monocytogenes, colony forming units of Listeria monocytogenes and Enterobacteriaceae in the sausage samples were analysed. The sensory evaluation was organised after getting Listeria monocytogenes testing results. The moisture content, water activity and salt content significantly differed (p < 0.05) among samples, no differences were established in pH, taste and flavour liking. The presence of Listeria monocytogenes was not established in samples which indicates that the producer properly applies a hurdle technology in fermented sausage production. Sensory evaluation results showed higher scores for texture and appearance in fermented sausages with glucono-delta-lactone. The study results confirmed that fermented sausages with glucono-delta-lactone during 3 weeks of drying can achieve corresponding safety criteria and sensory properties which are set for semidry fermented sausages.
Show more [+] Less [-]Agriculture Policy Scores of Selected Countries Through the Technique for Order of Preference (TOPSIS) Method
2021
Madiyoh, Abdulhakim | Turan, Özlem | Gürlük, Serkan
The purpose of this paper is to demonstrate the performance of agricultural sectors in the Association of Southeast Asian Nations (ASEAN) countries using selected criteria, to identify the deficiencies in agricultural policies, to explore competitive advantages and to guide food and nutrition policies. The analyses of this research use the secondary of time series data between the years 1967 - 2016 from 10 countries including; Brunei Darussalam, Cambodia, Indonesia, Laos PDR, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam which are the member of ASEAN. This research uses the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method and the data used for the mentioned countries include the following criteria; total agricultural production value of the land, self-sufficiency of animal products criteria, self-sufficiency of crop products criteria, rural population rate, greenhouse gas emissions from agriculture, and value of foreign trade in agricultural products. The result of proximity coefficients calculated with the TOPSIS method, which according to the number of proximity and maximum benefit analysis should be done according to the order of preference. It is stated that Thailand, Philippines and Indonesia were the most successful countries in the agricultural policy performance in 1967. As for last decades, Malaysia became the most successful country in agricultural policy performance. We can infer from the results that Malay industrial sector triggered the agricultural sector by supplying financial investment atmosphere.
Show more [+] Less [-]Green Transportation in the Šiauliai Regional Companies
2021
Beniušienė, Ineta | Jankauskienė, Aida
A relevant and practical research object is analysed in the article – the implementation resolution of green transportation and the benefits of using such means. In this article, object is analysed from the interdisciplinary position, i.e. from the perspective of transportation, one of the logistical subsystems, and sustainable environment. The transportation department is undoubtedly an important guarantor of economic and industrial development. Despite the worldwide importance of transportation in everyday activities, the transportation also poses the risk for human health and life quality, for it is one of the biggest consumer of oil products and significantly contributes towards air pollution. Despite many theoretical and empirical researches, Šiauliai region still lacks an approach towards the implementation possibilities and studies revealing the benefits of green transportation. A comparative analysis has been performed by using the survey data, collected from 402 workers, responsible for transportation, working for Šiauliai regional companies. According to the results of the research for implementation situations of green transport in Šiauliai regional companies, the representatives of regional companies understand the importance of green transport, and more and more companies aim to reduce the environmental risk and to become more competitive. Integrated transportation by combining several means of transport, cargo consolidation by combining small orders and big orders, and ecological driving are the green transportation measures implemented most in regional companies. The typical benefits of green transport are increased environmental friendliness and improved relationship with consumers.
Show more [+] Less [-]Slaughter Results, Meat Chemical Composition and pH of Aberdinangus, Hereford and Limousin bulls
2021
Muizniece, Inga | Kairisa, Daina
Beef production must combine the interests of both producers and consumers, taking into account the sustainable use of environmental resources. The aim of the study was to analyze and compare the slaughter results, meet chemical composition and pH value of three beef breeds – Aberdinangus (AA), Hereford (HF) and Limousin (LI) bulls. The bulls were fattened on Latvian and Lithuanian farms, mainly using grass forage. The breed and age of bulls before slaughter significantly affected all slaughter results, except for fat class. From the meat chemical composition traits, the bull breed and age before slaughter had a significant effect only on the protein content. LI bulls showed the highest carcass weight 301.1±6.8 kg (p<0.05), dressing percentage 58.2±1.1% (p<0.05) and conformation score 3.56±0.18 points. The best fattened carcasses were obtained from AA bulls - 2.43±0.20 points. Muscle samples of musculus longissimus (M. longissimus) bulls of LI breed showed higher content of moisture (72.0±1.0%), protein (23.0±0.2%), ash (1.1±0.0%) and cholesterol (56.7±6.6 mg 100 g⁻¹). AA breed bulls showed higher total fat (6.6±1.2%) and iron content (13.1±0.6 mg). The highest pH was observed in the meat obtained from AA bulls – 6.0±0.1, LI and HF breed bulls showed pH 5.8±0.0 and 5.8±0.1 respectively. Correlation analysis showed a significant, strong positive correlation between cold carcass weight and dressing percentage for AA and LI bulls, r=0.90 and r=0.88, respectively. For LI breed bulls, a strong positive correlation was also found between the cold carcass weight and the conformation score (r=0.98, p<0.01).
Show more [+] Less [-]Pre-treatment Effect on Physical and Microbial Parameters of Smoked Baltic Sprats
2021
Puke, Santa | Galoburda, Ruta
Smoked sprats are delicious and nutritionally valuable product. Besides protein, it contains high amount of unsaturated fatty acids and fat soluble vitamins. Nowadays, human interest for fish product consumption is increasing. It leads to the demand for increased shelf life of the smoked sprats. One way to prolong the shelf life is to use some pre-treatment prior to smoking. The aim of study was to analyse the effect of pre-treatment on smoked Baltic sprat quality and microbiological parameters. Various compositions of brine using salts (NaCl, CaCl₂) and acetic acid in different proportions were used for fresh sprat pre-treatment. Pre-treatment had the influence on physical parameters; pre-treated samples had higher salt and lower moisture content, and lower pH, which allowed prolonging the shelf life of smoked sprats. The highest pH was in the control sample 6.6, and it allowed growth of yeasts, moulds, Pseudomonas spp., and mesophilic and facultative anaerobic microorganisms. The results demonstrated that after two-week storage of the smoked sprats the growth of moulds (1×10² CFU g⁻¹) was observed only for smoked sprats without pre-treatment (control sample), indicating the positive effect of pre-treatment. Salmonella spp., Clostridium perfingens, Listeria monocytogenes, and Escherichia coli were not detected in any of the analysed samples. After pre-treatment in brine, containing combination of NaCl and CaCl₂, smoked fish had darker colour compared to control sample or sample with sodium chloride only. Any of applied pre-treatments, except brine containing NaCl, made firmer texture of the smoked fish.
Show more [+] Less [-]The Efficiency of Different Wood Coatings against Water Surface Absorption
2021
Iejavs, Jānis | Ruļuks, Oskars | Laiveniece, Laura | Jakovļevs, Vilnis | Pugovičs, Kārlis | Liše, Sigita | Spulle, Uldis
In the market of the Latvia different wood surface coating materials suitable for use in outdoor conditions are offered, but available information on the efficiency of these against direct water exposure is insufficient. For structural timber building elements, such as glued laminated timber (GLT), the surface coating should be applied taking into account technological, visual or colour changes (ISO 7724:1984) and – last, but not least – economic aspects are considered. Wood surfaces coated with coating materials, such as varnishes, paints, etc. can stabilize some properties such as movement of moisture content, dimensional changes and attack by microorganisms and fungi. The changes in the moisture content of timber may influence such important parameters as mechanical properties and the total life time of the structural timber elements. A study has been conducted with the aim of assessing the efficiency of coating materials used for wood protection against water absorption. In this study, six different commercial coating products used for the treatment of spruce (Picea Abies L. Karst.) and pine (Pinus Sylvestris L.) samples were tested. The efficiency of different coating substances was assessed using two modified test methods according to the standards EN 382-2 (1994) and EN 927-5 (2006), determining the surface water absorption after immersion in water for 24 h and the dynamics of water absorption of the glued laminated timber for 696 h kept in water. As a result of the study, it has been ascertained that organic solvent-based commercial coating products are more efficient against short-term and long-term wood water absorption compared to oil-based coating materials.
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