167 research outputs found
STATE AND PERSPECTIVES IN COMPETITIVENESS OF ONE FARM TYPE IN SERBIA
In the paper is analyzed competitiveness of Serbian family dairy farms in lowland region in 2007, with some aspects of possible perspectives. Globalization process, expected EU integrations and set of free trade agreements will expose Serbian farms in close future to higher level of competition. Identified structural changes, refers on dairy farms concentration and specialization in lowland region in recent years. Estimated model of cost function revealed that family farms with bigger herd size have lower average costs of milk production. Economic efficiency, measured in terms of cost efficiency, shows that larger dairy farms are more efficient. But, not all smaller farms are inefficient. Due to good management some smaller farms are competitive on national market. Milk price volatility in period 2007 to 2009 hurts all farms, but the most farms with higher average costs, which are usually inefficient dairy farms.Competitiveness, Dairy enterprise, Dairy farm, Milk production, Serbia, Agribusiness, Livestock Production/Industries,
Obstacle-aware Adaptive Informative Path Planning for UAV-based Target Search
Target search with unmanned aerial vehicles (UAVs) is relevant problem to
many scenarios, e.g., search and rescue (SaR). However, a key challenge is
planning paths for maximal search efficiency given flight time constraints. To
address this, we propose the Obstacle-aware Adaptive Informative Path Planning
(OA-IPP) algorithm for target search in cluttered environments using UAVs. Our
approach leverages a layered planning strategy using a Gaussian Process
(GP)-based model of target occupancy to generate informative paths in
continuous 3D space. Within this framework, we introduce an adaptive replanning
scheme which allows us to trade off between information gain, field coverage,
sensor performance, and collision avoidance for efficient target detection.
Extensive simulations show that our OA-IPP method performs better than
state-of-the-art planners, and we demonstrate its application in a realistic
urban SaR scenario.Comment: Paper accepted for International Conference on Robotics and
Automation (ICRA-2019) to be held at Montreal, Canad
Online Informative Path Planning for Active Classification on UAVs
We propose an informative path planning (IPP) algorithm for active
classification using an unmanned aerial vehicle (UAV), focusing on weed
detection in precision agriculture. We model the presence of weeds on farmland
using an occupancy grid and generate plans according to information-theoretic
objectives, enabling the UAV to gather data efficiently. We use a combination
of global viewpoint selection and evolutionary optimization to refine the UAV's
trajectory in continuous space while satisfying dynamic constraints. We
validate our approach in simulation by comparing against standard "lawnmower"
coverage, and study the effects of varying objectives and optimization
strategies. We plan to evaluate our algorithm on a real platform in the
immediate future.Comment: 7 pages, 4 figures, submission to International Symposium on
Experimental Robotics 201
Informative Path Planning for Active Field Mapping under Localization Uncertainty
Information gathering algorithms play a key role in unlocking the potential
of robots for efficient data collection in a wide range of applications.
However, most existing strategies neglect the fundamental problem of the robot
pose uncertainty, which is an implicit requirement for creating robust,
high-quality maps. To address this issue, we introduce an informative planning
framework for active mapping that explicitly accounts for the pose uncertainty
in both the mapping and planning tasks. Our strategy exploits a Gaussian
Process (GP) model to capture a target environmental field given the
uncertainty on its inputs. For planning, we formulate a new utility function
that couples the localization and field mapping objectives in GP-based mapping
scenarios in a principled way, without relying on any manually tuned
parameters. Extensive simulations show that our approach outperforms existing
strategies, with reductions in mean pose uncertainty and map error. We also
present a proof of concept in an indoor temperature mapping scenario.Comment: 8 pages, 7 figures, submission (revised) to Robotics & Automation
Letters (and IEEE International Conference on Robotics and Automation
A New Approach to Evaluation of University Teaching Considering Heterogeneity of Studentsā Preferences
AbstractStudentsā evaluations of teaching are increasingly used by universities to evaluate teaching performance. However, these evaluations are controversial mainly due to fact that students value various aspects of excellent teaching differently. Therefore, in this paper we propose a new approach to student evaluation of university teaching based on data from conjoint analysis. Conjoint analysis is a multivariate technique used to analyze the structure of individualsā preference. In particular, our approach accounts for different importance students attach to various aspects of teaching. Moreover, it accounts explicitly for heterogeneity arising from student preferences, and incorporates it to form comprehensive teaching evaluation score. We have conducted survey and confirmed applicability and efficiency of the proposed approach
Effects of n-3 Fatty Acids Supplementation on Plasma Phospholipids Fatty Acid Composition in Patients with Obstructive Jaundice- a Pilot Study
Nutritional and immunological status of patients with obstructive jaundice is usually severely altered, with high mortality rates. The n-3 polyunsaturate fatty acids (PUFA), particularly eicosapentaenoic acid (EPA, 20:5 n-3), posess potent immunomodulatory activities. Thus, our aim was to compare the plasma phospholipid fatty acid (FA) composition of these patients with healthy subjects, as well as before and after 7 days preoperative supplementation with high doses of EPA (0.9Ā g per day) and docosahexaenoic acid (DHA, 22:6 n-3, 0.6Ā g per day). We found impaired FA status in obstructive jaundice patients, especially EPA, DHA and PUFA, but significantly increased content of total n-3 FA, 22:5 n-3 FA and particularly EPA, which increased more than 3 fold, after 7 days supplementation. In addition, the n6/n3 ratio significantly decreased from 14.24 to 10.24, demonstrating severely improved plasma phospholipid profile in these patients after the intervention
Specifics of marketing in overcoming discrepancies on the market of agricultural products
In this paper, authors examine the role of marketing in overcoming the discrepancies between supply and demand, with a special emphasis on agricultural markets. Discrepancies arise as a result of specialization in production and mass production, whereby individual companies tend to make the best use of existing resources and produce large amounts of a narrow assortment, because in this way they achieve the best business results using economy of scale. Consumers, on the other hand, have diverse needs, preferences and aspirations and often demand non-standardized, customized and specific products. The result is a conflict of relatively narrow supply of individual companies and the diverse needs for products and services manifested by consumers. One of the fundamental roles of marketing is to efficiently connect supply and demand and eliminate the existing discrepancies, which is achieved by use of effective marketing channels. Specifics of agricultural products to a certain extent make harmonization of supply and demand even more difficult, taking into account the existence of a large number of small producers on the supply side, the limited seasonality of agricultural products, specific requirements related to storage, and dispersion of demand, which hinders the realization of all marketing activities in overcoming discrepancies. Taking into account previous specifics, there is a need of specialization of intermediaries who act in marketing channels, in order to efficiently eliminate discrepancies between supply and demand in the market of agricultural products.U ovom radu autori ispituju ulogu marketinga u prevazilaženju nesklada izmeÄu ponude i tražnje, sa posebnim akcentom na tržiÅ”ta poljoprivrednih proizvoda. Neskladi nastaju kao posledica razliÄite ciljne usmerenosti proizvoÄaÄa i potroÅ”aÄa. Nosioci ponude teže da na najbolji naÄin angažuju postojeÄe resurse i proizvedu Å”to veÄe koliÄine proizvoda uskog asortimana, kroz specijalizaciju i masovnu proizvodnju, jer tako ostvaruju najbolje poslovne efekte koji proistiÄu iz pristupa koji podrazumeva ekonomiju obima. PotroÅ”aÄi, sa druge strane, imaju raznolike potrebe, preferencije i težnje i Äesto zahtevaju nestandardizovane, prilagoÄene, specifiÄne proizvode. Tako dolazi do sukoba relativno limitirane ponude pojedinaÄnih kompanija i raznovrsnih potreba za proizvodima i uslugama koje ispoljavaju potroÅ”aÄi. Jedna od osnovnih uloga marketinga u ovom smislu je da efikasno spoji ponudu i tražnju i otkloni postojeÄe nesklade, Å”to se prvenstveno realizuje koriÅ”Äenjem efikasnih kanala marketinga. SpecifiÄnosti tržiÅ”ta poljoprivrednih proizvoda u odreÄenoj meri dodatno otežavaju sprovoÄenje marketing aktivnosti usmerenih na usaglaÅ”avanje ponude i tražnje, imajuÄi u vidu postojanje velikog broja sitnih proizvoÄaÄa na strani ponude, sezonalnost dospevanja poljoprivrednih proizvoda, posebne zahteve u skladiÅ”tenju, ali i razuÄenost tražnje. Uz uvažavanje navedenih specifiÄnosti, nameÄe se potreba specijalizacije uÄesnika koji deluju u kanalima marketinga, kako bi se efikasno eliminisali neskladi izmeÄu ponude i tražnje na tržiÅ”tu poljoprivrednih proizvoda
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