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Active class - work forms versus student passivity
2007
Augustaitiene, I., Lithuanian Univ. of Agriculture, Akademija, Kauno reg. (Lithuania)
Recently, the graduates should not only be technically competent, but also they should be skilled in communication and team work, have social and global awareness, be self directed and prepared for life-long learning. Knowing of languages contributes to student personal development. However, passivity of the students in the English classroom is among the factors limiting not only active engagement in academic tasks, acquisition of communicative skills but also soft skills needed for future profession. Therefore, at Lithuanian University of Agriculture, where student-active teaching and learning has been applied the study of the most acceptable class work forms for breaking passivity and improving students' motivation in the classroom for learning English as a foreign language was performed. The most persistent problem for the passive students who are afraid of speaking is the inability to find right words to express themselves (31%), and the fear of making mistakes, criticism, and sounding foolish (almost 55%). The application of the active class-work forms seems to behave well over fighting the passivity and enabling acquisition of the most important skills both for foreign language acquisition and becoming perspective future employees. Team work in created by a teacher relaxed atmosphere in the fitted classroom was found to be one the ways for breaking silence and passivity of the students in the English class room.
显示更多 [+] 显示较少 [-]The model of students' patriotic attitude development during the study course 'Rural tourism'
2007
Dunska, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Luse, N., Latvia Univ. of Agriculture, Jelgava (Latvia)
The migration of many rural youngsters to bigger cities and other countries in order to find a place for better life and job is not only economic but also educational and up-bringing problem nowadays. The development of the Latvian countryside is closely connected with the investment of educated young people in the long-term creative development of the native country. Latvia University of Agriculture students consider that one of the reasons of leaving their native land rather easily is because they were not purposefully brought up in the field of the patriotism and the feelings of belonging to their native country. Higher educational establishments apply different study models dependent mainly on the aims of educational institutions. The aim of this work is to develop a study model of 'Rural tourisms' taking into account that the study course 'Rural Tourism' has its up-bringing potential which can help to increase the development of students' patriotic attitude during the acquisition of Latvian cultural and historic inheritance. The priority of the study course 'Rural Tourism' in Latvian higher educational establishments is supposed to contribute to the development of students' entrepreneurial skills but this direction does not increase the development of students' patriotism. The above mentioned developed study model is based mainly on the dynamics of the relationship between the study program and the development of students' patriotism.
显示更多 [+] 显示较少 [-]The influence of organic acids and phytogenic additive on pigs performance
2007
Jansons, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Nudiens, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
A study was conducted to determine efficiency of an organic acids and phytogenic additives on pigs' growth processes and digestive tract microflora. The feed of the control group (C) did not contain the additives. The feed of the organic acid group (A) contained 6 kg of organic acids additive per tonne feed for pigs after weaning, 4 kg per tonne feed for grower pigs, and 3 kg per tonne feed for finished pigs. The feed of the phytogenic additive group (F) contained 0.5% of phytogenic additive per tonne feed for pigs after weaning, and 0.2% per tonne feed for grower and finished pigs. The feed of organic acids plus phytogenic additives group (A+F) contained 6 kg of organic acids additive per tonne feed for pigs after weaning, 4 kg per tonne feed for grower pigs, and 3 kg per tonne feed for finished pigs 0.5% of phytogenic additive per tonne feed for pigs after weaning, and 0.2% per tonne feed for grower and finished pigs. Compared to groups pigs from the group (F) had by 9.7%, group (A+F) - by 8.3 % and from group (A) had by 3.2% higher mass. The bests results of feed conversion were found in the group (A+F) - 2.84 kg, which was by 8.5% less than in the group (C), whereas the group (F) had by 5.1% and group (A) - by 6.7% better results than the control group. The results of Duodenum and Rectum microflora analyses showed that use of organic acid and phytogenic additives reduced mould yeast Staphylococcus sp. colony formed units (CFU gE-1).
显示更多 [+] 显示较少 [-]Effect of selenium on thiamine, riboflavin and pantothenic acid content in different grains
2007
Duma, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The effect of selenium on the content of thiamine (vitamin B1), riboflavin (vitamin B2), as well as pantothenic acid (vitamin B5) in wheat (Triticum aestivum L), hull-less barley (Hordeum vulgare L.) and hull-less oats (Avena sativa L.) grains during germination were investigated. The winter wheat grain variety 'Zentos', hull-less barley and hull-less oats were used for study. Grains were soaked for 120 hours totally in solutions containing selenium from 10 to 200 mg lE-1 in the form of sodium selenate (Se+6). Grains with moisture content of 43%-44% were let to sprout at ambient temperature of 18+-2 deg C. The content of B1, B2 and B5 vitamins in germinated grains were determined using standard methods. Laboratory studies showed that changes in vitamin B1, B2 and B5 content depend on selenium concentration and kind of grains. Selenium additives promote biochemical activity of vitamin B1 and content of this vitamin decreases after 5 days' germination in all investigated grains at all applied selenium concentrations. Selenium concentrations of 10 and 25 mg lE-1 promote forming of vitamin B2 in wheat, barley and oat grains. The changes in vitamin B5 content depend on selenium concentration and kind of grains.
显示更多 [+] 显示较少 [-]Investigation of the quality of vegetable oils
2007
Vucane, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kuka, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
Vegetable oils are essential providers of energy to a human body; they play important role as a foodstuff. During processing and storage of vegetable oils, they may undergo molecular changes adverse to the human organism affecting the quality of the oils. The content of fatty acids of fresh rapeseed, linseed and hemp oils and of the mixture of rapeseed (800 g kgE-1) and linseed (200 g kgE-1) oils was determined by the method of gas chromatography (GH). Alpha - , delta - and gamma - tocopherols were analyzed in the vegetable oils by the methods of the highly effective liquid chromatography (HPLC). The hemp oils contain the indispensable polyunsaturated fat acids: linoleic acid - 53.0%, and linolenic acid - 23.2%. Such proportion of the fatty acids (3:1) is considered optimal in the nutrition. When using both hot and cold pressure technology for the obtaining of oil, it is possible that the polycyclical aromatic hydrocarbon - Benzo[a]pyrene - may be created and influenced the quality of the oil. The environment also affects the content of the lead in the oils. The density of the various vegetable oils at the temperature of 20 +- deg C proved to be within the limits of 0.917 and 0.942 kg dmE-3.
显示更多 [+] 显示较少 [-]Problematic character of forest land transformation
2007
Bara, G., Latvia Univ. of Agriculture, Jelgava (Latvia)
In order not to decrease the significance of a forest in the environmental maintenance and its role in the national economy, Latvian Forest policy needs to ensure that the existing forest areas are not decreasing, establish forest land transformation restrictions, thus, maintaining a long lasting development of forests. The preconditions for the change of the forest land use is one of the instruments for the state policy realisation, with the help of which a long-term development of forests can be ensured. At the moment working out the land policy in Latvia on a country level is being started. The publication is in the context of setting strategic targets for forestry and human resource development planning strategy, within the framework of Latvian forest and related department national programme. Due to the reasons mentioned, the topic discussed in the article is a problem of the day, and the research in this direction has got both theoretical and practical significance. The author investigate the forest land transformation process, by analysing normative acts and political documents in the article, as well as by summarising statistical data about the relevant processes in Latvia and in the world, during last six years. The issues, related to the forest land transformation process have been covered in the article; it has been analysed whether there are cases when a necessity arises to review the existing normative regulations. The answers have been given how to eliminate identified shortcomings, contradictions or problems.
显示更多 [+] 显示较少 [-]Use of simulation method for the analysis of wood resource flow
2007
Oss, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
The task of this paper is to create a simulation model of wood resource flow, enabling analysis of the flow of resources to the customer. The model consists of four modelling steps - the study of the system, the creation of conceptual and logical model, as well as data analysis. The model has been developed in UML (Unified Modelling Language) diagrams and the simulation model has been created using software EXTEND Industry. For the simulation of the model the scenario has been created. Based on this scenario, extended scenarios have been developed. Model of basic simulation represents the loading of resources into the transport, transportation, discharging from the transport and the return to the loading point. Using this basic scenario, the extended scenario has been created. This scenario analyzes the flow of wood resources to the customer, taking into account two criterions restricting the flows - assortment to be processed and the distance from the loading place to the customer's location. Extended scenario allows to analyze the load of each sector, as well as to follow each unit existent in the process of simulation. There are attributes of information (type, assortment etc.) added to the unit equivalent to 1m**3 of wood resources. These attributes can provide information about the unit flow within any part of the process.
显示更多 [+] 显示较少 [-]Productivity of grey alder (Alnus incana (L.) Moench) stands
2007
Miezite, O., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dreimanis, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Area of grey alder stands is 190.6 thousand ha that is 6.8% of the total area of forests in Latvia with average volume 31.3 million m**3 4.9% of total yield is in the state forests, but 95.1% in the forests of other managers. Scientific literature affirms that grey alder is easy growing trees species. Its stands are quick - growing and wood has high heating capacity. Empirical data in 1 - 10 years old stands are collected from 25 m2 sample plots, 15 in each stand. Data from older (11 - 30 years) stands are obtained by 6 - trees - sample - plot method, from 180 trees in each stand. Number of trees (y) in the stands diminishes with age (x) that is characterized by regression equation y = 72534xE-1.1488. The division of the number of trees in diameter classes characterizes distribution of trees diameters in stands and trees differentiation processes within the stands. At the age of 1 - 5 years, grey alder stems were in diameter classes under 2 cm but at the age 6 - 10 years - 2 and 4 cm. In 11 - 15 years old stands 89% of all the measured trees are included in four (4 - 10 cm) diameter classes. It pointed to growing differentiation of diameters of the trees. Starting from age 16 - 20 years, 76 - 89% of the trees were of four to five diameter classes (10 - 18 cm). The average standing volume in 11 and 15 year old stands was 110 m3 haE-1 and it increased step by step to 180 m3 haE-1 in the stands of age 26 - 30 years. The basal area in the age of 15 - 30 years varied between 20 - 26 m2 haE-1. The average diameter reached 15 cm in stands of 25 -30 years.
显示更多 [+] 显示较少 [-]Relationship of birch (Betula sp.) plywood bending properties determined according to the European standards EN 789 and EN 310
2007
Zudrags, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Tuherm, H., Latvia Univ. of Agriculture, Jelgava (Latvia)
The manufacturers of wood-based panels are interested to get easy and cheap method for determination of characteristic values of panels. The correlation between European standards EN 789 and EN 310 tests results can be used as an alternative procedure for determination of characteristic values of bending properties. The correlations between two results of bending properties determined by testing methods of European standards EN 789 and EN 310 are studied in this paper. The ratio of EN 789 test results divided with EN 310 test results (ratio of EN 789/EN 310), depending on panel thickness and glue type, was examined. Samples from 846 panels of birch (Betula sp.) plywood with thickness ranging from 6.5 to 30 mm and two glue types - phenol formaldehyde and melamine urea formaldehyde resin - were used for verification of the correlations. The results show that the panel thickness influences the ratio of EN 789/EN 310 and the highest ratio were found between 12 and 15 mm panels. When the panel thickness is increased or decreased, the ratio of EN 789/EN 310 decreases significantly. The regression equations for each thickness of plywood are presented. The difference between plywood glued with phenol formaldehyde and melamine urea formaldehyde resin glues was not found.
显示更多 [+] 显示较少 [-]Evaluation criteria of protected landscape aesthetic quality
2007
Zigmunde, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The study focuses on protected landscape aesthetic quality assessment where the main problem is how to associate aesthetical and ecological approaches. High ecological quality does not often correlate with high landscape aesthetic quality, and this relationship may differ depending on specific ecosystem. The landscape aesthetic quality assessment historically developed on two approaches. One of them - expert approach, which has dominated in landscape planning and management practice, and the second - perception approach, which has dominated in research. In protected landscape aesthetic quality assessment traditional approaches will be revised by ecology and green philosophy aspects. The study example regards important natural and protected areas around river Lielupe - from Jelgava city to Kalnciems. This is the landscape with high heritage, natural, biological values and it is also living, recreation place for people. Therefore, cooperation between aesthetic and ecological approaches in landscape assessment is needed. The outdoor investigations were carried out in autumn 2006. There were photographs and video materials on the first stage of investigation. In the second part aesthetic quality of views was analyzed with expert approach. There were three main groups of evaluation criteria of protected landscape aesthetic quality. These covered design and compositional outlines - features, their quality and relationship among these features. The results showed that not all criteria are suitable and effective for evaluation of protected landscape aesthetic quality because of restriction of specific ecological conditions.
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