RSComPro: An Open Communication Protocol for Remote Sensing Systems

The remote sensing protocol (RSComPro) is a communication protocol, which has been developed for controlling multiple remote sensing systems simultaneously through a UDP/IP and TPC/IP network. This protocol is meant to be open to the remote sensing community. The scope is the implementation of so-called wind scanners even with an heterogeneous set of devices. In this paper the main design characteristics of the protocol are presented. Moreover, experiences of two implementations based on long range lidars of type WLS200S are shown. Mainly, six systems of this type are being operated in two windscanner systems performing measurements for wind energy research, respectively by DTU Wind Energy and ForWind at University of Oldenburg. The first system has been used for synchronized measurements of three-dimensional wind speed at multiple points in the atmosphere at coastal sites of Denmark. The second performs wind farm measurements at the offshore site alpha ventus. First experiences show high requirements on device and campaign setup for precise measurement of wind fields for wind energy research. Preliminary results of the first campaigns are shown

A six-beam method to measure turbulence statistics using ground-based wind lidars

A so-called six-beam method is proposed to measure atmospheric turbulence using a ground-based wind lidar. This method requires measurement of the radial velocity variances at five equally spaced azimuth angles on the base of a scanning cone and one measurement at the centre of the scanning circle, i.e.using a vertical beam at the same height. The scanning configuration is optimized to minimize the sum of the random errors in the measurement of the second-order moments of the components (u,v, w) of the wind field. We present this method as an alternative to the so-called velocity azimuth display (VAD) method that is routinely used in commercial wind lidars, and which usually results in significant averaging effects of measured turbulence. In the VAD method, the high frequency radial velocity measurements are used instead of their variances. The measurements are performed using a pulsed lidar (WindScanner), and the derived turbulence statistics (using both methods) such as the u and v variances are compared with those obtained from a reference cup anemometer and a wind vane at 89 m height under different atmospheric stabilities. The measurements show that in comparison to the reference cup anemometer, depending on the atmospheric stability and the wind field component, the six-beam method measures between 85 and 101% of the reference turbulence, whereas the VAD method measures between 66 and 87% of the reference turbulence

Ekonomski aspekti primene mašina i oruđa za uređenje zemljišta po površini i dubini

Problems that occur when processing the soil with heavy mechanical type of composition can not be solved without changing the existing cultivation system. Soils with heavy mechanical type of composition demand a cultivation system that ensures preservation of natural potential and fertility resources. Bearing this in mind, the objective of this research is to examine the economic consequences of applying new types of machines and tools for the arrangement of soil’s surface and depth, then to detect the most important factors influencing this and finally to contribute successfully to the formulation of the answers on questions is their use profitable and under what conditions. The results of this study suggest that is possible to expect the positive effects of applying new technologies and new machines and tools for the arrangement of soil’s surface and depth.Problemi koji se javljaju pri obradi zemljišta sa teškim mehaničkim sastavom ne mogu se rešiti bez promene postojeće tehnologije obrade zemljišta. To podrazumeva primenu novih tehnologija obrade i novih mašina i oruđa, koji treba da obezbede optimalnu potrošnju pogonske energije, rada i ostalih resursa, a da se pri tome obezbedi maksimalno iskorišćavanje prirodnog potencijala plodnosti zemljišta i rodnosti biljaka. Zbog toga sve više raste značaj istraživanja problema vezanih za ovu oblast, pri čemu se nikako ne sme zapostaviti ekonomski aspekt. Imajući to u vidu cilj ovog rada je da se sa ekonomskog aspekta sagledaju efekti i posledice primene novih tehnologija i novih mašina i oruđa za uređenje zemljišta po površini i dubini kao i da se utvrde najvažniji faktori od kojih zavisi isplativost njihove primene uz nastojanje da se na taj način doprinese što uspešnijem formulisanju odgovora na pitanje da li je i pod kojim uslovima njihova primena opravdana. Na osnovu dosadašnjih rezultata istraživanja moguće je očekivati pozitivne efekte primene analiziranih mašina i oruđa što je od presudne važnosti prilikom donošenja odluke o opravdanosti njihovog uvođenja

Uticaj promene cene goriva na optimizaciju ukupnih troškova upotrebe poljoprivredne mehanizacije za obradu zemljišta

Serbian agricultural producers are facing currently with a large number of challenges that significantly influence their business activities. One of them is for sure a high fuel price. The recent fuel price increase has caused a lot of concern among agricultural producers regarding its impact on operating costs and farm profitability. However, those higher costs will probably reflect themselves onto direct reduction in profit in the short run because the producers' possibilities are limited as to the changes they can economically make. While no one knows with certainty what will happen in the future, the current developments on the world market as well as the analysts’ estimates indicate that we are likely to see continued high diesel fuel prices. Bearing this in mind, the objective of this research is to emphasize an importance of the fuel price change for optimization of total operating costs of the tillage agricultural machinery, then to detect the most important factors influencing this change and finally to contribute successfully to the formulation of the answers on mentioned questions. The results of this study suggest that for an increase of the agricultural machinery utilization efficiency as well as for minimization of their operating costs, it is necessary to start making more adequate management decisions. This is certainly one of the safe ways for alleviation of the consequences caused by the high fuel price mostly influenced by the world fuel market trends.Poljoprivredni proizvođači u Srbiji suočavaju se sa velikim brojem izazova koji značajno utiču na njihovo poslovanje. Jedan od njih je svakako visoka cena goriva. Skorašnje povećanje cene goriva nateralo je mnoge od njih da se zapitaju kakav će to uticaj imati na troškove proizvodnje tj. kako će se odraziti na profitabilnost poslovanja gazdinstva. Ono što je izvesno je da će u kratkom roku, ovako visoka cena dovesti do smanjenja profita, zato što su mogućnosti vlasnika da u kratkom roku učine ekonomska prilagođavanja prilično limitirane. I dok niko sa sigurnošću ne može da pretpostavi šta će se dešavati u budućnosti, trenutna kretanja na svetskom tržištu i procene analitičara govore da i dalje treba očekivati održavanje cene na visokom nivou. Imajući to u vidu, cilj ovog istraživanja je da se ukaže na značaj promene cene goriva za optimizaciju ukupnih troškova upotrebe poljoprivredne mehanizacije za obradu zemljišta, da se otkriju najvažniji faktori koji na to utiču i da se sagleda njihov uticaj, uz nastojanje da se na taj način doprinese uspešnijem formulisanju odgovora na napred postavljena pitanja. Na osnovu dosadašnjih rezultata istraživanja može se konstatovati da je za povećanje efikasnosti korišćenja poljoprivredne mehanizacije i minimiziranje troškova njihove upotrebe, od presudnog značaja celishodno i blagovremeno sprovođenje adekvatnih mera iz oblasti menadžmenta. To je svakako jedan od sigurnih načina za ublažavanje posledica izazvanih visokom cenom goriva na čije formiranje prevashodni uticaj imaju kretanja na svetskom tržištu derivata