83 research outputs found
Copper production in Majdanpek in sixties and seventies of the 16th century
In this paper the practice of mine Majdanpek during sixties and seventies of the XVI century has been investigated with an accent on copper production. The attention has been also given to various subjects from considering copper treatment and use to forbidden activities connected to copper illegal production and trade with Persia
Phylogenetically Conditioned Possibilities of the Realization and of the Development of Complex Movements at the Age of 7 Years
Upon entering a school the seven-year olds ( 2 months) underwent a systematic, experimental,
specially programmed, eighteen-month-long transformational procedure.
The objective of the procedure was to develop the abilities and to observe the growth and
the development of children, both girls and boys. The data were processed by means of
discriminant analyses in each of the three control points. There was a total sample of
487 children. With regard to the phylogenetic characteristics of a human, it may be said
that the basic abilities connected with phylogenetic development may be clearly recognized,
precisely in such a way that children replicate this development throughout their
earliest childhood. Most probably, the basic ability was the ability to maintain a postural
balance, followed by the ability of movement control. Then came object manipulation
by upper extremities, followed by the significance of resistance to inertial forces
while moving, and ultimately the control of complex movements of the whole body
Changes in Crude Protein Content with Advancing Maturity in Lucerne
The main determinants of the quality of lucerne forage are digestibility and protein content (Julier et al., 2001) as well as crude fibre content. In the early vegetative phases, the crude protein content of the leaves and stems is the highest and crude fibre content the lowest (Katic et al., 2003). The aim of this study was to determine the rate of change in crude protein levels at different stages of growth and development
Genetic Variability of Yield and Its Components in Winter Forage Pea Cultivars
The genus Pisum (peas) is rich in variability of morphological traits. It provides an excellent basis for breeding, but is also one of the reasons for the still undefined status of Pisum taxons (MihailoviÄ et al., 2004a). The majority of forage pea cultivars used belongs to subspecies sativum and variety arvense (Maxted & Ambrose, 2000). The objective of our study was to determine genetic variability of yield and its components in six winter forage pea cultivars of different origin and to evaluate their breeding potential
Uticaj kvasaca, probiotika i enzima u obrocima na proizvodnost visokomleÄnih krava u tranzicionom periodu
The main goal of this paper was to investigate the influence of some additives included into high yielding dairy cows rations to overcome the problems in early lactation. These substances directly affect the productive performances of dairy cows as well as udder health. The commercial name of investigated preparation is 'YEASTURE' and it is composed of live yeast cultures selected from three strains Saccharomyces cerevisisiae in combination with probiotic bacteria and enzymes (Lactobacillus casei, Streptococcus faecium, Aspergillus oryzae, Lactobacillus acidophilus, 1,3-b and 1,6 D-Glucan, hemicellulase, Protease, Cellulase, Alpha amylase) which have the ability to modify the fermentation in rumen stimulating the development of ruminal bacteria and increasing the fibre digestion. Effects of this preparation have been investigated on 60 Holstein-Friesian cows divided into two groups. The diets were identical, and trial group received also 10 g of preparation Yeasture daily. Application of Yeasture started 15 days prior to calving and lasted until 60th day of lactation As a research result improved in vitro disappearance of diet dry matter from roughage (alfalfa hay, maize silage and ensiled sugar beet pulp) was established. Preparation Yeasture influenced quantity and composition of the milk. The difference between trial and control group was 2.57 kg 4%FCM or 8.70% (P (lt) 0.01) and 7.16% milk fat (P (lt) 0.05).Trial group supplemented with Yeasture showed lower somatic cells count by 7.3 percent points what indicated better health of cow's udder. Based on the presented results it can be concluded that inclusion of preparation Yeasture into diets for dairy cows in transition period can be recommended.Period zasuÅ”enja i rana laktacija karakteriÅ”u se brojnim problemima koji mogu da se uspeÅ”no premoste ukljuÄivanjem dodataka u hranu kao Å”to su probiotici, kvasci, enzimi i dr. U radu su ispitani efekti preparata yeasture koji predstavlja kompoziciju ovih dodataka a koji je ukljuÄen u obroke krava dve nedelje pre i osam nedelja posle telenja u koliÄini od 10 g po grlu dnevno. UkljuÄivanje pomenutih dodataka uticalo je na poboljÅ”anje svarljivosti suve materije kabastih hraniva (sena lucerke, silaže cele biljke kukuruza i siliranog rezanca Å”eÄerne repe) Å”to je konaÄno znaÄajno uticalo na poboljÅ”anje proizvodnih performansi odnosno poveÄanje koliÄine mleka za 10.86%. Jednovremeno pomenuti dodaci povoljno su uticali na popravljanje zdravstvenog stanja vimena krava Å”to se odrazilo na smanjenje broja somatskih Äelija za 7.3 procentnih poena. Najvažniji parametri krvi pre i posle eksperimenta kretali su se u fizioloÅ”ki optimalnim granicama. Navedeni argumenti su dovoljan razlog da se ukljuÄivanje pomenutih supstansi u obroke visokomleÄnih krava u periodu zasuÅ”enja i rane laktacije preporuÄi u proizvodnji mleka
Coupled wake boundary layer model of wind-farms
We present and test the coupled wake boundary layer (CWBL) model that
describes the distribution of the power output in a wind-farm. The model
couples the traditional, industry-standard wake model approach with a
"top-down" model for the overall wind-farm boundary layer structure. This wake
model captures the effect of turbine positioning, while the "top-down" portion
of the model adds the interactions between the wind-turbine wakes and the
atmospheric boundary layer. Each portion of the model requires specification of
a parameter that is not known a-priori. For the wake model, the wake expansion
coefficient is required, while the "top-down" model requires an effective
spanwise turbine spacing within which the model's momentum balance is relevant.
The wake expansion coefficient is obtained by matching the predicted mean
velocity at the turbine from both approaches, while the effective spanwise
turbine spacing depends on turbine positioning and thus can be determined from
the wake model. Coupling of the constitutive components of the CWBL model is
achieved by iterating these parameters until convergence is reached. We
illustrate the performance of the model by applying it to both developing
wind-farms including entrance effects and to fully developed (deep-array)
conditions. Comparisons of the CWBL model predictions with results from a suite
of large eddy simulations (LES) shows that the model closely represents the
results obtained in these high-fidelity numerical simulations. A comparison
with measured power degradation at the Horns Rev and Nysted wind-farms shows
that the model can also be successfully applied to real wind-farms.Comment: 25 pages, 21 figures, submitted to Journal of Renewable and
Sustainable Energy on July 18, 201
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